RU2563755C1 - Sewing machine with multi-thread chain stitch and device of prevention of ripping stitch - Google Patents

Abstract

FIELD: personal use articles.

SUBSTANCE: in the sewing machine with multi-thread chain stitch and device of prevention of ripping stitch the base of the needle plate (11) is divided into the left (11L) and the right (11R) parts of the needle plate, and the left part is used to connect the needle plate and to support the swivel drive (30) of the thread hanging hook (3), and the right part of the base of the needle plate is attached to the sewing machine bed (B) and is used for fixing the retaining element (4), the stopper cylinder (42) and the thread control cylinder (32). In addition, the left part of the base of the needle plate has an ability of removal-mounting on the upper part of the sewing machine bed (B) using the screw fastener elements (102), which enables to provide sufficient space for setting the stitch, maintenance and replacement of various parts and components located inside the sewing machine bed, to perform easily these procedures, without additional time and labour expenditures, while providing consistently stable quality of stitching, and implementation of the function of prevention of ripping stitch of chain stitch.

EFFECT: increase in efficiency of operation.

14 cl, 23 dwg

Description

Technical field

The present invention relates to multi-thread chain stitch sewing machines. In the general case, such a machine is presented in the form of a multi-thread chain stitch machine with a horizontal cylindrical platform, with needle thread and looper thread, equipped with a seam opening prevention device, which usually takes place at a certain part of the end of stitched seams of a multi-thread chain stitch.

State of the art

A sewing machine with a multi-thread chain stitch (multi-thread chain stitch) with a horizontal cylindrical platform includes: one or more needles, seasoned with threads and moving up and down; the looper moving back and forth, while the thread supported by the looper moves in a direction substantially orthogonal to the vertical needle path. In this sewing machine, the loop of the needle thread formed below the needle plate is caught by the looper during its translational movement, while the needle thread is intercepted (intercepted) by the looper thread held by the looper, resulting in a multi-thread seam of the chain stitch.

The main disadvantage of this type of seams formed by a multi-thread chain stitch sewing machine follows from the following problem. As shown in FIG. 20, when the end portion of the looper thread 10 cut at the end of the seam is drawn in the direction of the arrow in FIG. 20, the looper thread 10 slides out of the last loops of the needle thread 20a and 20b, respectively, formed by the needle threads 20 and 20. The slip tends to spread toward the sewing start point, thereby causing the entire seam to unfold.

This unblocking occurs similarly to the unblocking of multi-strand chain stitch seams formed by the needle thread or the threads of two or more needles and the looper thread.

In order to prevent the blooming characteristic of seams formed by multi-thread chain stitch sewing machines, the applicant has already developed and filed patent applications related to the described type of multi-thread chain stitch sewing machines with a seam-opening prevention device (hereinafter referred to as references to the technical solution described in filed patent application of the present applicant).

The implementation of the device to prevent the opening of the seam for the sewing machine multi-thread chain stitch according to the technical solution described in the patent application already filed (here describes a two-needle sewing machine), has the following configuration, including: (I) needles 2 and 2 (Fig. 11-17), the holding needle threads 20 and 20, moving up and down with respect to the lowermost position of the needle, are set at a distance on the sides almost at the level of the middle part of the needle plate P, as shown in FIG. 21-23; (II) looper 1 (see FIGS. 11-17), which can move forward and backward by holding the looper thread 10 in the direction of lower position of the needles A and A, and the catching threads of the loops 20a and 20b formed below the needle plate Ρ while moving forward; (III) a hook for suspending the thread 3, which can move in and out with respect to the looper 1 and swing around a vertically located support axis 30 between the standby position away from the looper 1, as shown in FIG. 21, and the position of the capture of filaments adjacent to the looper 1, as shown in FIG. 23, in a plane almost parallel to the needle plate Ρ and the air cylinder (pneumatic cylinder) that controls the thread (hereinafter referred to as the thread control cylinder) 32 as a hook drive 3 for controlling the swing of the thread hanging hook from the standby position to the thread locking position; (IV) a pivoting (swinging) lever 9 located away from the needle plate P, further than the hook for hanging the threads 3, and swinging around the upright support shaft 90 in a plane substantially parallel to the needle plate Ρ so that the loop of the needle threads 20a and 20b , caught in the position of the loop hanging from the hook 3 of the thread hanging, are held in the holding position between the position of the hanging thread and the standby position, and the lever of the stopper (limiter) 4; (V) the pneumatic cylinder (air cylinder) of the stopper (hereinafter referred to as the stopper cylinder) 42 is used as a stopper drive for controlled swinging of the lock lever 4 from the engagement position, in which the lock lever 4 engages with a part of the rotary (swinging) lever 9, to a position away from engagement; (VI) connecting rod 35 for mutual engagement of the hook hanging the thread 3 and the rotary (swinging) lever 9; and (VII), the control unit 8 (Fig. 8), which selectively controls the actions of the cylinder that controls the thread 32, and the cylinder of the stopper 42 after normal sewing is completed, and also allows the loop of needle thread 20b, one of those caught on the thread in the hook position of the suspension of the thread, 3 to be held in the holding position, and so as to carry out a sewing action to execute at least one stitch while maintaining the holding state.

Structural elements and structural parts in the device for preventing the opening of the seam for the multi-thread chain stitch sewing machine from the technical solution described in the previously filed patent application (s) by the present applicant (Japanese Patent Application No. 2011016821, Japanese Patent Application No. 2011-115174) are identical or correspond to a device for preventing the opening of the seam, which can be used as an option for the present invention, described below. They are denoted by the same reference numbers as in the embodiment of the present invention, and their detailed description is omitted here.

In the previously filed patent application by the present applicant, after completion of conventional sewing, the above steps for forming the sewing stitch are performed by controlling the actions of the hook for hanging the thread 3, the locking lever 4 and the pivoting lever 9. As shown in FIG. 18, the looper thread 10 passes through the end of the loop of the needle thread 20a on the right side (left side in FIG. 18), which is formed as a result of the multi-thread chain stitch of seam Μ on the back of the fabric, and returns back before the needle thread 20, which slides along towards the back of the fabric when sewing one stitch to prevent the seam from opening, after which the thread is cut in a certain position after passing through the right end of the loop of the needle thread 20a. On the other hand, the needle thread 20 on the left side (the right side in Fig. 18), which slides toward the back (lower) surface of the fabric when one stitch is sewn, passes through the end of the needle thread loop 20b, finally forming it at the end of normal sewing on the back of the fabric, and allows the last loop of the needle thread 20b to be self-locking, thereby forming chain stitch seams. Then, the looper thread 10 enters a clamping state between the left needle thread 20 and the last left loop of the needle thread 20b, as shown in FIG. eighteen.

Although FIG. 18 shows a state in which the left end (last) loop of the needle thread 20b and the needle thread 20 are free to explain the weaving between the two, the actual last loop of the left needle thread 20b is tightened after the thread of the needle 20 passes through it, thereby entering a state similar to that of the last loop of the right needle thread 20a, as shown in FIG. 19. The looper thread 10 is tightly clamped between the thread of the needle 20 and the last loop of the thread of the left needle 20b, and is held in a state of hanging over the last loop of the thread of the left needle 20 and the loop of the left needle thread 20s formed immediately before. This retention is maintained even when a force exerted from any direction is applied to the looper thread 10, as shown in FIG. 19, thereby preventing the opening of the seam characteristic of the seam Μ of the multi-thread chain stitch.

Thus, a multi-thread chain stitch sewing machine with a seam opening prevention device operates in accordance with the technical solution described in the previously filed patent application of the present applicant. It is able to effectively prevent the occurrence of blooming inherent in the seams of a multi-thread chain stitch. However, in a multi-thread chain stitch sewing machine with a seam opening prevention device, the following problems remained unresolved.

Thus, in the technical solution described in the already filed patent application of the applicant of the present invention, as shown in FIG. 21-23, the hanging hook of the thread 3, the stopper lever 4, the pivoting lever 9, the thread control cylinder 32, the stopper cylinder 42 are structural elements supported laterally by a long and large base of the needle plate 11, which includes a needle plate P connected and fixed on the upper surface of the platform of the sewing machine. In particular, the reference axis 30 of the swing of the thread of the hook hanging the thread, 3 is supported in a position in the immediate vicinity of the back of the needle plate Ρ on the left side of the base of the needle plate 11. On the other hand, the stopper lever 4, the pivot lever 9, the thread control cylinder 32 and the stopper cylinder 42, respectively, are supported in a position away from the needle plate Ρ on the right side relative to the base of the needle plate 11. In addition, a connecting rod (connecting rod) 35 connected between the front end part of the otnogo arm 9 and the front end portion of the expanded portion 3c extended (held) so as to be folded forward from the support shaft 30 for rocking hooks, suspended thread 3. Reference numeral 6 in FIG. 21-23, the looper thread holder is indicated, fastened together with a hook for hanging the thread, 3 with fixing screws 60 and 60.

Thus, in the multi-thread chain stitch sewing machine described in the previously filed patent application by the present applicant, all structural elements of the seam opening prevention device are supported in the direction transverse to the long and large base of the needle plate 11. Therefore, if after the base of the needle plate 11 with the components of the device for preventing the opening of the seam installed and fixed on the upper surface of the platform of the sewing machine, it becomes necessary to adjust, for example, the stitch by correcting the position and loci (location, hodograph) of the elements performing the sewing action, which are located below the base of the needle plate 11 and inside the platform of the sewing machine, such as a looper and elements that activate it, or if it becomes necessary to carry out maintenance, for example, by replacing the various types of components included in the platform of the sewing machine, a wide working space sufficient to perform adjustment and maintenance cannot be ensured It is possible only by removing the needle plate P. Therefore, in order to provide the wide working space necessary for performing the operation, for setting and maintenance, it is necessary to completely temporarily remove the long and large base of the needle plate 11 from the platform of the sewing machine, after which the base of the needle plate 11 is installed in place in the platform of the sewing machine.

In particular, the air pipes 33 and 43 for supplying working air to the thread control cylinder (pneumatic cylinder) 32 and the stopper cylinder 42, respectively, are connected to these two cylinders. Thus, to perform an extremely troublesome and time-consuming operation, in which, when removing and attaching the base of the needle plate 11, these two air pipes 33 and 43 are pulled from the inside of the platform of the sewing machine, and it is necessary that both of them do not interfere with the removal and installation operations in addition, after these operations, the air tubes are pushed back into the interior of the platform of the sewing machine. However, even if, despite the troublesome and time-consuming task, the adjustment and maintenance operations are still carried out, there is a possibility that after all this, the stitching has worsened, and the function to prevent the opening of the seam cannot be reproduced. The elimination of this will require again troublesome and time-consuming operations, which suggests that the problem remains unresolved.

SUMMARY OF THE INVENTION

The present invention was created due to the foregoing circumstances, and its object is to provide a multi-thread chain stitch sewing machine with a seam opening prevention device by which the seam opening characteristic of multi-thread chain stitch seams can be effectively prevented, and it is very easy and simple to carry out maintenance such how to adjust the stitch by correcting the position of the elements involved in sewing, and replacing various types of components inside the seam platform machine without any problems and labor and time, allowing to achieve the prevention of opening of the seam and the constant reproduction of this function.

To achieve the above goal, a multi-thread chain stitch machine with a seam opening preventer in accordance with the present invention includes: a needle moving up and down holding a needle thread; a looper that can move back and forth while holding the looper thread in a direction substantially orthogonal to the vertical path of movement of the needle, and which catches the loop of thread formed below the needle plate with the needle while moving forward; and the base of the needle plate, including the base of the needle plate with a needle plate attached thereto, and it itself is attached to the upper surface of the platform of the sewing machine.

The multi-thread chain stitch machine forms seams of the multi-thread chain stitch on the fabric, allowing the looper to catch the needle thread loop formed below the needle plate by the needle, and then intercept (re-hook) the needle thread with the looper thread. very easy and simple, the thread of a multi-thread chain stitch with a device for preventing the opening of a seam includes: (A) a needle thread holder mechanism, which has (I) a thread suspension hook that can approach and move away from the looper and swing around a vertically support shaft in a plane almost parallel to the needle plate between the standby position away from the looper and the grip position of the thread close to the looper, and (II) the thread hook hook (hanging thread) to swing the hook to the o position fluid and clinging position of the thread; (B) a locking mechanism (III) comprising a locking element that is located farther from the needle plate than the hook, hanging the thread, the thread holding mechanism, and allows temporarily suspending and resuming swinging of the thread hanging hook, from the gripping position to the ready position so that the loop of the needle thread caught by the hook hanging the thread in the grip position of the thread remained in the holding position between the grip position of the thread and the standby position; and (IV) a stopper drive for holding and releasing the stopper element; (C) a connecting member for interlocking the thread of the hook hanging the thread, the thread holding mechanism, and the locking member of the locking mechanism; and (D) a control unit that controls the thread holding mechanism (needle thread holder mechanism) and the locking mechanism in combination with vertical needle movement, looper movement forward and backward, and fabric feed, so that the looper moves forward after normal sewing is finished, the hook hanging the thread, the thread holding mechanism, is carried near the looper, the loop of the needle thread captured in the grip position of the thread moves to the holding position, the resulting state is maintained until the loop of the needle thread It doesn’t go down through the loop of the thread caught by the looper, and after that, the sewing action for at least one stitch is considered to be completed.

The base of the needle plate is divided into two parts: the left support base of the needle platinum (left base) for attaching the needle plate to it and maintaining the rotary support shaft of the hook hanging the thread; and the right base of the needle plate for motionless support of the locking element, the hook drive and the stopper drive. The right base of the needle plate is attached to the platform of the sewing machine. The left base of the needle plate is mounted-removable and attached to the upper surface of the platform of the sewing machine using screw elements.

In a multi-thread chain stitch sewing machine with a seam opening prevention device having the above characteristic features, after stopping normal sewing, the looper moves forward, and the needle hook of the needle thread holding mechanism of the needle thread is carried near the looper, and the needle thread loop caught by the looper moves to the holding position, and in this condition, a sewing action in the amount of at least one stitch is considered completed. Accordingly, the previous loop of the needle thread is self-gripping by the needle loop carried by the falling needle, and the looper thread is held below the self-locking portion of the loop, thereby preventing slipping of the looper thread. That is, the opening of the seam can be reliably prevented even in the developmental stage.

In addition, in the present invention, the base of the needle plate attached to the platform of the sewing machine is divided into two parts: the left side of the base of the needle plate for attaching the needle plate to it and with the possibility of mounting the rotary support shaft of the hook hanging the thread, the needle thread holding mechanism; and the right side of the base of the needle plate for rigidly fastening the stopper element of the stop mechanism, the hook drive and the stopper drive. Thus, compared with the use of one long and large needle plate, as in the case of the machine described in the previously filed patent application of the present applicant, the attachment (installation) of the device to prevent the seam from opening to the platform of the sewing machine can be easily carried out with less effort, since the left and the right side of the base of the needle plate can be individually attached to the platform of the sewing machine, and the device to prevent the seam from opening can be mounted in the platform of the sewing machine s.

Moreover, if after the seam opening prevention device is mounted on the platform of the sewing machine, it becomes necessary to adjust the stitch by correcting the position and movement of the components to perform the sewing action, those located below the base of the needle plate and inside the platform of the sewing machine, such as the looper and looper drive elements, or if it is necessary to carry out maintenance, such as repairing or replacing various types of components, located below the base of the needle plate or inside the platform of the sewing machine, it will be necessary to remove the right side of the base of the needle plate with a solid attachment of the hook drive and the stopper drive to which the air pipes or electric power supply line are connected, however, a sufficiently wide working space can be provided by detaching and removing only the left side of the base of the needle plate from the platform of the sewing machine.

Thus, seam adjustment and maintenance, such as repairing and replacing various types of components located in the platform of the sewing machine, can be done very easily, simply and efficiently by manipulating the small and light left side of the base of the needle plate with which no feed tube air, no power line connected. This creates the effect that sewing is satisfactorily carried out and the preventive function of preventing the opening of the seam can be regularly performed with excellent reproducibility, thereby ensuring success in solving the problem that remains unresolved in the previously filed patent application of the present applicant.

In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the locking mechanism preferably includes: a locking element that is directly connected to the hook drive and moves linearly with respect to it; the pivot arm engages with and disengages from a part of the locking member; a spring for exciting the swing of the pivot arm in the direction in which the hook for hanging the thread is in the ready position; and a stopper drive for disengaging the pivot arm from a portion of the stopper member as a result of counteracting the force of the spring.

In this case, the action of the locking element in the opposite direction (action in the direction in which the hook hanging the thread is in the ready position) is carried out as a result of the excitation of the spring force. Thus, a stop actuator for actuating a pivot arm that engages with or disengages from a portion of the retainer element may be capable of pushing to control the retainer element. Therefore, the use of a pneumatic cylinder as a stopper drive allows the use of a single-acting type air cylinder, thereby achieving a reduction in size and lowering the cost of the stopper drive.

In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the pivoting (swinging) lever in the locking mechanism is preferably attached to a movable base attached laterally to adjust the right side of the base of the needle plate. In this case, lateral adjustment of the position of the movable base relative to the right side of the base of the needle plate, coordination of the time interval during which the looper leaves the loop of the needle thread supported by the hook hanging the thread can be easily and appropriately adjusted to verify the implementation of self-locking to prevent the seam from opening .

In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the thread hook of the thread holding mechanism and the stopper of the stopper mechanism are preferably firmly mounted vertically on-off (two-stage) on the lower surface of the right side of the base of the needle plate.

In this case, two drives are rigidly mounted on the right side of the base of the needle plate vertically in a two-position (two-stage) way, and, therefore, the flat space occupied by these two drives can be reduced for compactness, which allows them to be well located inside the platform of the sewing machine, compared to case when two drives are located in places separated from each other (side-by-side location) as in the case of the solution described in the previously filed patent application of the present applicant.

In a multi-thread chain stitch sewing machine with a seam opening prevention apparatus according to the present invention, the thread hook of the thread holding mechanism is preferably provided with a looper thread holder that holds the looper thread exiting the looper into the fabric in a more advanced position than the lower needle position by swinging together with the hook hanging the threads of the needle thread holding mechanism around the support shaft in a plane substantially parallel to the needle plate between the locking position vata thread, hold position, and wait position.

In this case, the looper thread is held in position in front of the lower needle position by the looper thread holder, which interacts with the hook for hanging the thread. This simple design allows the looper thread to accurately position itself with the needle thread. Accordingly, self-locking (self-locking) can be reliably performed in order to more reliably prevent the seam from opening.

In a multi-thread chain stitch sewing machine with a seam opening prevention apparatus according to the present invention, the looper thread holder is preferably attached in an adjustable position to the thread hanging hook. In this case, the relative position between the needle and the looper thread can be correctly set, and self-locking (self-locking) can be performed more reliably to further increase the prophylaxis of the effect of the dissolution of the seam.

In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the needle thread holding mechanism hook drive and the stopper (stop) mechanism stopper drive are preferably both in the form of pneumatic (air) cylinders (hereinafter referred to as cylinders).

In this case, the thread hanging hook in the needle thread holding mechanism and the pivot arm in the locking mechanism can operate with high speed based on a control signal from the control unit, thereby providing a reliable and effective preventive effect of preventing the seam from opening after normal sewing.

Instead of cylinders, electromagnetic solenoids or similar devices can be used as drives.

In a multi-thread chain stitch sewing machine with a seam opening prevention device according to the present invention, it is preferable that the pin protrudes upward from the end of the connecting part of the connecting element, and part of the connecting end of the thread hanging hook is preferably provided with a connecting hole that can be worn on top of the contact pin directed up.

In this case, when the left side of the base of the needle plate is removed from the platform of the sewing machine in the upward direction as a result of detaching it from the upper surface of the platform of the sewing machine to perform maintenance such as repairing and replacing various components placed inside the platform of the sewing machine, the connection between the hook hanging the thread and the connecting element can only be released by raising the left side of the base of the needle plate, without requiring any onerous operations, so x as a detachment and extraction screw, which the connection to the connecting member and the hook hanging or stretch yarn connecting pin. In addition, after adjustment and maintenance, the thread hanging hook and the connecting element can only be returned to the set connection state by firmly attaching the left side of the base of the needle plate to the platform of the sewing machine from above. This saves even more time and labor during adjustment and maintenance.

In a multi-thread chain stitch sewing machine with a seam prevention device according to the present invention, the left side of the base of the needle plate or platform of the sewing machine is preferably provided with: protruding pins for positioning the left side of the base of the needle plate on the platform of the sewing machine in a plurality of positions apart from the set connected parts and parts of the separation-connection by means of screw elements, and the platform of the sewing machine or the left side of the base needle The plate is preferably provided with pin holes for engaging with pins.

In this case, when the left side of the base of the needle plate is attached and detached from the platform of the sewing machine, the left side of the base of the needle plate can, of course, be located in a predetermined position on the platform of the sewing machine due to the contact between the plurality of pins and pin holes. Therefore, even when the left side of the base of the needle plate is reconnected and disconnected from the platform of the sewing machine, each time adjustment and maintenance is performed, the left side of the base of the needle plate can be attached to the platform of the sewing machine in a constantly set position and orientation. Therefore, in addition to ordinary sewing, the preventive function of preventing the seam from opening can also be constantly carried out and absolutely reproduced.

The seam opening prevention device according to the present invention is accordingly applicable to a horizontal cylindrical platform type of a multi-thread chain stitch sewing machine.

Brief Description of the Drawings

The invention is illustrated by figures of drawings (schemes) 1-23, for the understanding of which the following notation is used: List of notation indicated in the figures: 1 - looper; 2 - needles; 4 - locking element; 3 - hook hanging the thread; 6 - looper thread holder; 8 - control unit; 9 - rotary (swinging) lever; 10 - looper; 11 - the base of the needle plate; 11L - left support base of the needle plate; 11R bases for attaching the cylinder (right base of the needle plate); 20 - needle thread; 20a, 20b loop of threads; 30 - vertically protruding support axis; 32 - thread control cylinder (hook drive); 35 - connecting rod (connecting element); 42 - cylinder stopper (limiter) (drive stopper); 91 - spring; 92 - the base of the mounting of the rotary (swinging) lever (moving base); 102 - screw elements; 103 - pin; 104 - hole for the pin; 110 - pin; 111 - connecting hole; A - extreme lower position of the needle; In - a platform of the sewing machine; Ρ - needle plate; Μ - multi-thread stitch of a chain stitch.

FIG. 1 is a perspective view of a multi-thread chain stitch sewing machine with a horizontal-type cylindrical-platform seam opening preventer in accordance with an embodiment of the present invention.

FIG. 2 shows a perspective view illustrating the structure of the main seam parts of the seam opening prevention apparatus in a multi-thread chain stitch sewing machine with a horizontal type cylindrical platform.

FIG. 3 is a perspective view showing a state in which a part of the structure of the main part of the seam anti-swell prevention device is removed.

FIG. 4 is a plan view showing a structure of a main part of a seam opening prevention apparatus.

FIG. 5 is a bottom plan view showing the main parts for explaining the structure of the locking mechanism and its first action in the seam opening prevention device.

FIG. 6 is a bottom view explaining the structure of the locking mechanism and its second action.

FIG. 7 is a bottom view explaining the structure of the locking mechanism and its third action.

FIG. 8 is a bottom view explaining the structure of the locking mechanism and its fourth action.

FIG. 9 is a block diagram showing a configuration of a control system of a multi-chain chain stitch sewing machine with a horizontal cylindrical platform with a seam opening prevention device.

FIG. 10 is a timing chart explaining a content of an operation of a control unit in a seam opening prevention device;

FIG. 11 provides an explanation of the first action of the seam opening preventive prevention device.

FIG. 12 provides an explanation of the second action of the seam opening preventive prevention device.

FIG. 13 provides an explanation of the third action of the seam opening preventive prevention device.

FIG. 14 provides an explanation of the fourth action of the seam opening preventive prevention device.

FIG. 15 provides an explanation of the fifth action of the seam opening preventive prevention device.

FIG. 16 provides an explanation of the sixth action of the seam opening preventive prevention device.

FIG. 17 provides an explanation of the seventh action of the seam opening preventive prevention device.

FIG. 18 is a view of a seam structure of two needle sewing machine of a multi-thread chain stitch obtained by the present invention, as viewed from the back of the fabric;

FIG. 19 is an explanatory drawing for preventing blooming of the seam structure shown in FIG. eighteen.

FIG. 20 is a view of the overall design of the seam in the area at the end of sewing, as viewed from the back of the fabric

FIG. 21 is a plan view, approximately, showing the structure of the main parts of the weld prevention device working according to the technical solution described in the previously filed patent application of the present applicant;

FIG. 22 is a bottom view, approximately showing the structure of the main parts of the device for preventing the opening of the seam working according to the technical solution described in the previously filed patent application of the present applicant.

FIG. 23 is a plan view explaining the effect and condition of the main parts of the joint opening prevention apparatus operating in accordance with the technical solution described in the previously filed patent application of the present applicant.

The implementation of the invention

One embodiment of the present invention is described below with reference to the accompanying drawings.

In FIG. 1 shows a general view of a multi-thread chain stitch sewing machine with a horizontal type cylindrical platform in accordance with an embodiment of the present invention. FIG. 2 and 3 show the structure of the main parts of the seam opening prevention device in the construction of a multi-thread chain stitch sewing machine with a horizontal type cylindrical platform in accordance with the present invention. FIG. 4 is a plan view showing the structure of the main parts of the weld prevention device. Further description is made using the terms “left,” “right,” “forward,” and “backward,” indicated by arrows in FIG. 2-4. The term “forward” means the side next to the sewing operator. The term “back” refers to the side away from the sewing operator. The terms “left” and “right” mean left and right when viewed from the front from the side of the sewing operator.

In the present embodiment, structural elements and structural parts identical or corresponding to the technical solution described in the previously filed patent application of the applicant of the present invention described with reference to FIG. 21-23 using the same reference numerals.

As shown in FIG. 1, in a multi-chain chain stitch sewing machine with a horizontal cylindrical platform in accordance with the present embodiment of the present invention, the shoulder of the sewing machine C and the platform of the sewing machine B are elongated almost horizontally to the left from the upper position and lower position of the body part D, respectively. As shown in FIG. 4, the multi-thread chain stitch sewing machine with a horizontal cylindrical platform includes: looper 1, two needles 2 and 2 (see Fig. 11-17), the base of the needle plate 11 attached to the upper surface of the platform of the sewing machine B, prevention device a dissolving seam Η is built into the base of the needle plate 11, and the needle plate Ρ is fixed to the base of the needle plate 11. The needles 2 and 2 are moved up and down by the needle bar drive mechanism. The letters A and A in FIG. 2 and 4 indicate the lower needle positions (needle lowering positions) 2 and 2, respectively. The lower positions of the needles A and A are set on the sides at a distance and inside the middle part of the needle plate R. Looper 1 moves forward and backward (to the left - movement forward and to the right - movement in the opposite direction) due to the action of the looper drive mechanism. The solid line in FIG. 4 indicates the state in which looper 1 has moved to the left front position, and the dashed line in FIG. 4 indicates the state in which looper 1 has moved to the right rear position. As shown by the solid line in FIG. 4, the front end portion of the looper 1 in the left front position extends to the left of the positions of the needles A and A. As shown by the dashed line in FIG. 4, the front end of the looper 1 in the right rear position is to the right of the positions of the needles A and A.

A multi-thread chain stitch sewing machine with a horizontal cylindrical platform sews a fabric (not shown) located on the needle plate P as a result of the movement of the needles 2 and 2 up and down and the movements of the looper 1 left forward and right back. The fabric is pressed to the needle plate Ρ with a foot (not shown), and fed in the direction indicated by arrow Υ in FIG. 4 as a result of the action of the fabric feed mechanism installed inside the platform of the sewing machine B. The feed mechanism includes a conveyor that repeats such movements in which the gear rack, protruding from the needle plate P, moves in the opposite direction and moves in the forward direction when immersed under the needle plate P. The fabric is periodically fed to the conveyor in the direction of the arrow Υ.

The aforementioned needle bar drive mechanism, looper drive mechanism, and fabric feed mechanism are well-known mechanisms that work together synchronously mutually due to the energy coming from the spindle of a sewing machine (not shown). The needles 2 and 2 respectively hold the needle threads 20 and 20 (see Fig. 11-17), pass through the fabric and reach a position below the needle plate Ρ during a break in the supply of tissue, after which these needles move up and passes through the fabric in the direction up. The looper 1 holds the thread of the looper 10 (see Fig. 11-17), and moves to the left at the same time as the needles 2 and 2 begin to move upward, thereby catching the loops 20a and 20b of the threads of the needles 20 and 20, which are formed below needle plate R. The fabric is fed when the needles 2 and 2 move up. Needles 2 and 2 move downward when passing through the feed fabric, and catch the thread of looper 10, supported by looper 1 stretched to the right. The multi-thread chain stitch sewing machine forms a multi-thread chain stitch on the fabric, repeating the above steps.

The device for preventing the opening of the seam H, included in the design of the multi-thread chain stitch sewing machine described above with a horizontal cylindrical platform, includes: a thread holding mechanism, a locking mechanism, a connecting rod 35 as a connecting element for interlocking the hook for hanging the thread 3 (described below) with a thread holding a mechanism; locking element 4 (described below) of the locking mechanism; and control unit 8 (described below).

The thread holding mechanism includes a thread hanging hook 3, a cylinder controlling the reciprocating movement of the thread 32 in the form of a hook drive for controlling the swing of the thread hanging hook 3 around a vertical protruding support axis 30 between the standby position away from looper 1 and the engagement position next to the looper 1. The reference axis 30 as the center of swing of the hook for hanging the thread 3 is located in close proximity to the right angle of the back side of the needle plate Ρ and is fixed to the base of the needle plate eleven.

The hook for hanging the thread 3 has an arcuate curved shape and continuously takes shape so as to be folded in the direction of the front end of the support arm 3E protruding from the left end of the support axis 30. The front end of the hook for hanging the thread 3 is facing the lower position of the needles A and A c the left end of the lower side of the needle plate P. The protruding portion of the hook 3b is formed at the front of the end of the hook hanging the threads 3. The support arm 3e has an extended portion 3c, protruding forward from the support axis 30, and one to the end of the connecting rod 35 is connected to the front end portion of the protruding portion 3c.

As shown in FIG. 4, the looper thread holder 6, having an arcuate curved shape, is fastened together with the base part of the thread hanging hook 3 with two fixing screws 60 and 60. The front end part of the looper thread holder 6 projects forward substantially along the left side of the thread hanging hook 3 and collides into the lower the position of the needles A and A with the front position of the front of the end of the hook hanging the threads 3. The receiving part of the looper thread 6a branched into two parts is formed on the front end part of the looper thread holder 6. Thread holder etlitelya 6 allows adjustment position relative to the hook suspension string 3 by turning the fastening screws 60 and 60. Tilt provides retention looper 10 of the looper thread receiving portion 6a on the front end.

As shown in FIG. 5-8, the locking mechanism includes a locking element 4, which is attached to the front end part (left end part) of the output shaft 31 of the cylinder 32 controlling the thread by means of a fixing screw 36 and can be mutually moved in a straight transverse direction due to expansion and contraction thread control cylinder 32 by supplying air through an air tube 33; a pivot arm 9 engaged with and disengaged with a part of the locking element 4; a spring 91, which allows the pivoting lever 9 to engage with a part of the locking element 4 and gives swing energy to it in the direction in which the hook for suspending the thread 3 is in the ready position; and a locking cylinder 42 of the same type of action (pushing type in the left direction), as a locking drive, which forcibly releases the pivot arm 9 from the side of the part of the locking element 4 against the action of the swing force by the spring 91.

The output rod 41 of the locking cylinder 42 is configured to swing the pivot arm 9 counterclockwise against the action of the oscillating force of the spring 91 because the stopper 42 is pushed to the cylinder drive in the left direction by the working air supplied through the air tube 43. The pivot arm 9 is attached by the upper surface of the pivot arm ( movable mounting) 92 so that it can swing around the center of the protruding vertical support axis 90. The pivot arm 9 has a claw gear 9a on the front end part for engaging with part of the locking member 4. As shown in FIG. 5, the pivot arm 9 contacts the lateral part of the locking element 4 due to the driving force of the spring 91 while the locking element 4, due to the driving force, moves to the left by expanding the stitch of the cylinder controlling the thread 32, that is, at a time when the hook for hanging the thread 3 moves to the standby position. As shown in FIG. 6, the pivoting (swinging) lever 9 moves clockwise around the support axis 90 as a result of the transfer of force from the spring 91, and the engaging claw 9a at its front end enters into a engaged state with a part of the locking element 4, while the locking element 4 is controllably moved to the right side due to the reduction of the cylinder controlling the thread 32.

As shown in FIG. 7, allowing the compressed thread control cylinder 32 to somehow resume compression, the engaging claw 9a at the front end of the swing arm 9 engages with a part of the locking element 4, thereby temporarily stopping the locking element 4 to the left, In a state in which 4 the locking element thus temporarily suspended (paused), the hanging hook of the thread 3 moves to the holding position between the standby position and the hooking position of the thread, and remains at the expense of the connecting rod 35. At this time, part of the hook 3b at the front end of the hook suspension string 3 moves from the yarn engagement position shown in FIG. 4 (between the lower positions of the right and left needles A and A) to the left rear of the lower position of the left needle A, and grabs the thread of the left needle 20 and holds it in the holding position. The looper thread holder 6 moves forward to the front of the looper 1, and the receiving part of the looper thread 6a at its front end holds the looper thread 10 in the most forward (advanced) position compared to the lower position of the left needle

Further, as shown in FIG. 8, the pivot arm 9 pivots (pivots) counterclockwise, counteracting the swing force of the spring 91, allowing the output rod 41 to be pushed to the left while expanding the stopper cylinder (limiter) 42. This swing allows the engaging claw 9a at the front end of the pivot (swing) arm 9 to detach from parts of the locking element 4, thereby releasing the temporary locking element 4 from the temporary suspension.

Therefore, the thread control cylinder 32 undergoes maximum expansion and the hook for hanging the threads 3 and the thread holder of the looper 6 are alternately returned to the standby position through the connecting rod 35.

As described above, in the present embodiment, the thread hanging hook 3 and the looper thread holder 6 of the needle thread holding mechanism rotates to the standby position, the thread engaging position, and the holding position by expanding and contracting the thread control cylinder 32 and the lock cylinder 42 .

The multi-thread chain stitch sewing machine with a horizontal cylindrical platform in an embodiment of the present invention further includes a thread cutting mechanism 5 for cutting the needle thread 20 and the looper thread 10 after the sewing action has been performed. As shown in FIG. 16 and 17, the thread trimming mechanism 5 includes: a cutting hook 50; thread cutting knife 51; a flat spring 59 for pressing the thread cutting hook 50 against the sliding contact part between it and the thread cutting knife 51; and a thread cutter drive 58 (see FIG. 9). The thread cutting hook 50 has at its front end portion a first hook part 51 and a second hook part 53 that protrude backward. The thread trimming mechanism 5 is well known, and therefore its description and illustrations of other design features are omitted here.

In FIG. 9 shows a block diagram of a configuration of a multi-thread chain stitch sewing machine control system with a horizontal type cylindrical platform with a seam opening prevention device H described above. The pedal depression signal 21a and the pedal 21b feedback signal generated by the pedal switch 21, the needle position signal 22 is generated when the needles 2 and 2 are in close proximity to the top dead center, the thread cut signal 23, and the thread break signal 24 are respectively input to the block control 8 sewing machine multi-thread chain stitch.

On the other hand, the control unit 8 provides control signals to the thread control cylinder 32, stopper cylinder 42 and thread cutter 58, respectively. The hanging hook of the thread 3 and the looper holder 6 operate as described above, in accordance with the action of the control signals from the control unit 8 to the thread control cylinder 32 and stopper cylinder 42, and the thread cutting drive 58 of the thread cutting mechanism (not shown) expands and is compressed in accordance with the thread cutting signal 23 coming from is output from the control unit 8. The control unit 8 also provides control signals for the action, respectively, of the motor (motor) of the sewing machine 80 as a spindle drive source sewing machine, presser foot cylinder 81 for moving up and down the presser foot for pressing the fabric, an air cleaner 82 for sliding (cleaning) the needle threads 20 and 20, the parts have been shortened as described previously, the fabric feed speed reduction mechanism 83 for adjusting the fabric feed rate, and a looper thread holding mechanism 84 to limit the supply of looper thread 10 to looper 1.

The tissue feed reduction mechanism 83 reduces the tissue feed rate by changing the operation mode of the conveyor in the tissue feed mechanism. For example, the time during which the conveyor acts on the fabric located on the needle plate P is reduced by deviating the passage of the tissue feed with respect to the needle plate Ρ in such a way as to reduce the time during which the mechanism protrudes above the needle plate P, or unit the pitch of the tissue feed mechanism decreases with a change in the length of the lever for cyclic operation of the tissue feed mechanism. The mechanism for reducing the feed rate of fabric 83 of this type is well known, and therefore, detailed illustrations and their description are omitted here.

The looper thread holding mechanism 84 comprises a thread tension disk for compressing the middle portion of the looper thread 10 for feeding into the looper 1 and an actuator that operates to increase or decrease the compression force of the looper thread by the thread tension disk. The compression force of the looper thread by the thread tension disc increases increases the resistance acting on the looper thread 10, thereby holding back the looper thread 10. The holding mechanism of this looper thread 84 is well known, and therefore, a detailed image and description thereof is omitted here.

In conclusion, the sewing machine for forming a multi-thread seam of a chain stitch has: a control unit 8, which prevents the opening of a multi-thread seam of a chain stitch, allowing the hook of hanging the threads 3 and the holder of the thread of the looper 6 to act synchronously with the motor of the sewing machine 80, presser cylinder 81, air cleaner 82 , a mechanism for reducing tissue feed rate 83, and a loop retention mechanism 84.

FIG. 10 gives a time chart showing the time and contents of the operation of the control unit 8 for the purpose of opening a multi-thread seam of a chain stitch. The control unit 8 is a computer, including a processor, ROM and RAM. Prevention of the opening of a multi-strand seam in accordance with the time pattern shown in FIG. 10, is performed as a result of a series of operations under the control of a processor in accordance with a program stored in ROM.

FIG. 11-17 are operation drawings of a multi-thread seam-preventing device Η in a multi-thread chain stitch sewing machine with a horizontal cylindrical platform according to the present invention and showing the operating statuses of the thread, the hook for hanging the thread 3 and the thread holder of the looper 6, and the thread cutting hook when performing operations under control block 8 in accordance with the timing diagram of FIG. 10.

When the operator of sewing on the sewing machine stops normal sewing on the sewing machine, he stops the work by releasing the pedal of the sewing machine, and then the multi-thread chain stitch sewing machine with a horizontal cylindrical platform performs an operation to prevent the multi-thread seam from opening. In this case, the operator performs the work on the back of the pedal. A pedal switch 21 attached to the pedal outputs a pedal press signal 21a during a pedal press operation, and outputs a pedal signal back 21b in response to a reverse pedal operation.

When normal sewing is considered complete and the pedal for the sewing machine returns from the pressed state to the neutral state at the SI time in FIG. 10, namely, when neither the pedal 21a signal nor the pedal signal 21b is supplied from the pedal 21, the control unit 8 issues a stop command to the sewing machine 80, referring to the needle position signal received at the input.

Therefore, the machine is temporarily suspended in a state in which the needles 2 and 2 are located in close proximity to the top dead center, and the looper 1 moves to the left.

After that, the control unit 8 is on until the pedal is fed a signal operation backward. When the pedal back-off operation is performed, and the pedal back-off signal 21b is input at time S2 in FIG. 10, the control unit 8 starts operations to prevent the opening of the seam, as described below. When the signal for depressing the pedal 21a is supplied again from the pedal 21, the control unit 8 returns to normal sewing. Thus, the sewing operator can continue normal sewing by depressing the pedal again.

In FIG. 10 shows that although a neutral state is maintained for a period of time between S1 and S2, maintaining a neutral state is not necessary. The pedal at the end of normal sewing can be continuously transferred from the pedal depression state to the pedal reverse state. In this case, when passing through the neutral position by a shift, it enters a state of absence of a signal in which, in the absence of a signal for depressing the pedal 21a and in the absence of a return signal of the pedal 21b, a signal is generated. Using the no signal state as a trigger, the control unit 8 starts the operation to prevent the seam from opening after reaching the state in which the needles 2 and 2 rise almost to the top dead center and the looper 1 moves to the left, as described above.

Furthermore, during operation according to FIG. 10, although the pedal reverse operation at the time S2 continues during the operation of preventing the opening of the seam as described below, there is no need to continue the reverse operation of the pedal of stopping the operation of preventing the opening of the seam, and the operation of preventing the opening of the seam is continuously performed as a result of the operation of the control unit 8 even after the reverse signal of the pedal 21b is paused.

FIG. 11 shows the states of the needle 2 and 2 and looper 1 at the beginning of the seam opening prevention operation. The needles 2 and 2 have passed and are now located above the fabric on which the seams of the multi-thread chain stitch M are located, formed by two needle threads 20 and 20 and the thread of the buttonhole 10. Buttonhole 1 has moved to the left under the fabric, and is in a state of capturing the buttonhole of the needle threads 20a and 20a respectively, formed by the needles 2 and 2. When the needle of the threads 20 and 20 and the thread of the looper 10 are cut in this state, the final part of sewing is formed as shown in FIG. twenty.

After starting the operation to prevent the opening of the seam, the control unit 8, firstly, provides a working command to the control cylinder thread 32 from the output side. In response to this command, the thread processing cylinder 32 moves from the expansion state shown in FIG. 5 to the compression state shown in FIG. 6, and the locking element moves to the right under the action of the drive.

Accordingly, the thread hanging hook 3 and the looper thread holder 6 are moved from the standby (standby) position to the gear engaged by swinging around the support axis 30 with the locking member 4 and the connecting rod 35. At this time, the hook portion 3b of the front end of the thread hanging hook 3 engages the loop the needle threads 20a on one side (left side) and the pivoting lever 9 of the locking mechanism swing clockwise around the support axis 90 under the influence of the force of the spring 91, and the engaging claw 9a at its front end enters the state of the hook fusion with part of the locking element 4.

Immediately after this, the control unit 8 sends a working command to the thread control cylinder 32. By executing the work command, the thread control cylinder 32 expands somewhat from the state shown in FIG. 6 to the state shown in FIG. 7, and the locking element 4 under the influence of the actuator moves linearly in the left direction. During a slight expansion of the thread control cylinder 32, the engaging claw 9a at the front end of the swing arm 9 engages with a part of the locking element 4, thereby temporarily stopping the movement of the locking element 4 to the left. In a state in which the locking movement element 4 is temporarily suspended, as shown in FIG. 12, the suspension hook of the thread 3 is moved by the connecting rod 35 to the holding position between the standby position and the grip position of the thread, and remains there and holds the thread loop of the left needle 20a in the holding position. The looper thread holder 6 moves toward the front of looper 1, and the looper part receiving the thread 6a at its front end holds the looper thread 10 in a more forward (advanced) position than the lower position of the left needle A.

After the hook for hanging the threads 3 and the holder of the threads of the looper 6, thus move and remain in the holding position, the control unit 8 gives the working commands respectively to the engine of the sewing machine 80, the mechanism for reducing the feed rate of the fabric 83 and the mechanism for holding the threads of the looper 84 at a time S3 (Fig. 10). These control commands are received, consistent with the signal of the position of the needle 22 during the period of time during which the needles 2 and 2 move down and again up to the position near the top dead center. As a result, a sewing action is performed on one stitch on the fabric. Sewing on one stitch is carried out at a lower feed rate than normal sewing action due to the action of the mechanism to reduce the feed rate of fabric 83. Sewing one stitch is also carried out under the action of the mechanism of holding the looper thread 84 in a state in which the feed of the looper 10 into the looper 1 is restrained . This improves the degree of tension (compression) of the thread of the looper 10 at the end of sewing, thereby increasing the effect of preventing the opening of the seam, described below.

As shown in FIG. 12, hanging the thread hook 3 and the looper holder 6 continues to hold the needle thread 20 and the looper thread 10 until the fabric feed is complete, the needles 2 and 2 pass through the fabric and move down, and the left needle 2 passes through the thread loop needle 20a held hook hanging thread 3 and catches the thread loop 20a. At this time, the looper thread 10 supported by the looper thread holder 6 is located in front of the left needle 2, as shown in FIG. 12. Thus, the left needle 2 does not capture the looper thread 10, and the looper thread 10 is simply caught behind the looper 2 with the right needle 2.

At the time when the left needle 2 catches the thread loop 20a, in particular at time point S4 in FIG. 10, the control unit 8 allows the cylinder of the stopper 42 to expand from the stopper mechanism by transmitting the operation command of the cylinder of the stopper 42. Accordingly, the output rod 41 is pushed to the left by the drive. Therefore, as shown in FIG. 8, the pivoting (swinging) lever 9 rotates counterclockwise against the oscillating force of the spring 91, and the engaging claw 9a at the front end of the tilt of the lever 9 disengages from a part of the locking element 4, which allows the temporarily held locking element 4. to be released. After the temporary holding is stopped stop element 4, the thread control cylinder 32 expands to its maximum at time S4. Therefore, as shown in FIG. 13, the hanging hook of the thread 3 and the looper thread holder 6 reverse the movement from the holding position to the standby position, swinging (turning) around the support axis 30 with the locking element 4 and the connecting rod 35, after which the loop of the needle thread 20a and the looper thread are released from holding 10.

After this, looper 1 performs the retraction action to the right, while the needles 2 and 2 are lowered and slides out of the grip of the caught needle threads 20a. After slipping out of looper 1, as shown in FIG. 14, the right needle 2 enters the state of catching the thread of the looper 10, similarly to what happens during normal sewing, while the left needle 2 enters the state of catching the loop of the thread of the left needle 20a.

In this state, looper 1 moves to the forward movement to the left, and needles 2 and 2 go to the upward movement. As shown in FIG. 15, the looper 1 that moves forward to the left catches the loops of threads of the left and right needles 20a and 20b, and the needles 2 and 2, which move up, pass through the fabric in an upward direction. Accordingly, the thread 20 caught by looper 1 intercepts the looper thread in the position of the right needle 2, while the thread 20 performs the so-called self-locking (self-looping), i.e., the previously formed loop of the needle thread 20a is captured by the upper thread 20 in the position of the left needle 2.

After the end of the sewing action in one stitch, in the state in which the needles 2 and 2 move up in close proximity to their top dead center, looper 1 is in the position of close proximity to the end of the movement to the left. After that, the control unit 8 is in the standby state until the thread trimming signal 23 is executed. Upon receipt of the thread trimming signal 23 at time point S5 in FIG. 10, the control unit 8 allows the thread trimming drive 58 of the thread trimming mechanism to perform a predetermined operation by feeding the thread trimming 58 to the thread trimming drive. Accordingly, the thread hanging hook 50 reaches the end of the forward movement along the upper part of looper 1, as shown in FIG. 16. At this time, the first part of the hook 52 at the front end of the thread cutting hook 50 passes through the loops of threads 20a and 20b held by the looper 1 at the left side of the looper thread 10 extending from the front end of the looper 1 to the fabric, and the second part of the hook 53 is opposite the threads of the left needle 20 on the left side of it.

Subsequently, the thread cutting hook 50 located in front of the movement moves to the right in the opposite direction. At this time, the first part of the hook 52 catches the looper thread 10 and the second part 53 of the hook, after which it catches two needle threads 20 and 20.

The looper thread 10 and the needle threads 20 and 20 caught in this way are then pulled towards the pulled end of the thread cutting hook 50, and cut, being brought into sliding contact with an edge portion at the front end of the thread cutting knife 51, as shown in FIG. 17. The end portion of the cutoff of the thread of the looper 10 is held in a sandwich mode between the crochet hook of the thread 50 and the leaf (flat) spring 59 in a position closer to the looper 1 than the trim position.

The loop retainer thread holding mechanism 84 continues to operate and exerts a predetermined tension force on the looper thread 10 extending from the front end of the looper 1 to the fabric until the above thread trimming operation is completed. This ensures that the first part of the hook 52 at the front end of the thread cutting hook 50 catches and cuts the non-free (pinched) thread of the looper 10.

After the trimming operation described above, the control unit 8 waits until it receives the thread removal signal (cleaning signal) 24. When the thread removal signal 24 arrives at time point C6 in FIG. 10, the control unit 8 permits the air of the cleaner 82 to be supplied by sending a control command to the cleaner 82. The cleaner 82 blows air and disconnects the ends of the needle threads 20 and 20 that exit from the needles 2 and 2. After that, the control unit 8 allows the presser foot cylinder 81 raise the presser foot for pressing the fabric by issuing a control command to the cylinder of the presser foot 81 at time C7 in FIG. 10, thereby completing the process of preventing the seam from blooming.

The aforementioned sequence of operations for preventing the opening of the seam is carried out in a multi-thread chain stitch машине sewing machine with a horizontal cylindrical platform, as shown in FIG. 18. As shown in FIG. 18, the looper thread 10 passes through the inner part of the right loop of the needle thread 20a (the seams. Are visible from the side of the lower (back) surface of the fabric in the left side of Fig. 18), finally forming a multi-thread chain stitch M, on the back surface of the fabric, and then returning back to the position in front of the thread of the right needle 20, which passes through the bottom surface of the fabric during sewing in one stitch to prevent the seam from opening, and then is cut in a certain position after passing again through the inside of the loop of the right needle second thread 20a.

On the other hand, (on the right in FIG. 18), the left needle thread 20, which passes through the lower surface of the fabric during sewing, in one stitch to prevent opening, passes through the loop of the left needle thread 20b, finally formed on the lower surface of the fabric during normal sewing , and forms a chain stitch seam by self-locking the last loop of the left needle thread 20b, as described above. Therefore, as shown in FIG. 18, the looper thread 10 enters a clamping state between the left needle thread 20 and the last loop of the left needle thread 20b.

In FIG. 18, the last loop of the left needle thread 20b is shown in a loose (loose) state to illustrate the connection with the needle thread 20. However, as shown in FIG. 19, in fact, the last loop of the left needle thread 20b is tightly clamped after the thread 20 passes through it and is in the same state as the last loop of the right needle thread 20a. Then, when a part of the cut end of the looper thread 10 is pulled in the direction of the arrow, as shown in FIG. 19, the loop of the looper thread 10, passing in front of the right needle thread 20, is clamped and pulled into the last loop of the right needle thread 20a. As a result, the thread 20 enters a holding state between the thread of the looper 10 and the last loop of the right needle thread 20a, and the needle thread 20 and the thread of the looper 10 are knotted, as shown in FIG. 19. This node also provides resistance to the looper thread 10 and performs the function of preventing slipping from the looper thread 10.

Accordingly, in the state shown in FIG. 19, the left part of the self-locking (self-looping) and the right knot are visible together in order to prevent the multi-thread seam of the chain stitch M from opening.

The features of a multi-thread chain stitch sewing machine with a seam-preventing device and a non-opening function are described in detail above, namely, an improved structure used in the present invention to solve a problem that remains unresolved in an already filed patent application of the applicant of the present invention is described below focusing on FIG. 2-4.

As shown in FIG. 2-4, the base of the needle plate 11 attached to the upper surface of the platform B of the sewing machine is divided into left and right parts of the base of the needle plate 11L and 11R. The left part of the base of the needle plate 11L contains a needle plate Ρ with the possibility of removal-attachment to its upper surface using the set screw 100, and also supports the support axis 30 as the axis of rotation (swing) of the hook hanging the thread 3 of the thread holding mechanism.

The threaded holes 101 are formed in a plurality on the front and back parts (two portions) in the immediate vicinity of the left end part of the left base of the needle plate 11L, in particular, in areas away from the point of attachment of the needle plate Ρ in close proximity to the front end (left edge ) sleeves of the sewing machine C, indicated by a conditional line in FIG. 4. The left part of the base of the needle plate 11L is attached to the upper surface of the platform B of the sewing machine so that it is possible to remove and install (screw-untwisting, mounting and dismounting).

Further, as shown in FIG. 3, the upper surface of the platform of the sewing machine B and the left side of the base of the needle plate 11L are provided with pins 103 and pinholes 104, to which the pins 103 fit, in positions away from the two mounting positions using a set of screw elements 102. In the pinholes 104 are inserted and the pins 103 are engaged from above, thereby positioning the left part of the base of the needle plate 11L in a predetermined position and position relative to the platform of the sewing machine B. In this state, the set of screw elements 102 are screwed into the threaded holes Stia 102, thereby allowing the left side of the base needle plate 11L to be attached against the top surface of the platform of the sewing machine B.

Although the present embodiment describes and illustrates one in which the pins 103 protrude upward from the upper surface of the platform of the sewing machine B, the holes 104 are formed on the left side of the base of the needle plate 11L, or, alternatively, the pins 103 can protrude downward from the lower surface of the left side of the base of the needle plates 11L, and holes 104 may be formed in the upper surface of the platform of the sewing machine B.

On the other hand, the right side of the base of the needle plate 11R is a cylindrical base for attaching the thread control cylinder 32 and the locking cylinder 42 (hereinafter, the right side of the needle plate 11R is called the base of the cylinder mount). The above locking mechanism located in the lower part by the base of the cylinder 11R. More specifically, as shown in FIG. 5-8, the thread control cylinder 32 is rigidly fixed to the lower surface of the base of the cylinder 11R using the fixing screw 105. The lock cylinder 42 is located below the cylinder 32 of the thread control in a two-stage way (fashion), and the stopper cylinder 42 is rigidly mounted on the base of the cylinder 11R using the fixing screw 106.

The mounting base of the cylinder 11R is mounted in a “locked state” on the side surface of the platform of the sewing machine B using the set screw 107. The phrase “locked state” means a state in which the device to prevent the opening of the seam Η is fixed in position by the fixing screw set 107 in installation it into the platform of the sewing machine B, and is fixed in a predetermined mounting position after installation without performing any positional adjustments or the like for ystvy.

One end (right edge) of the connecting rod (connecting rod) 35 is connected by a locking element 4 of the locking mechanism with the possibility of rotation by means of a contact screw (screw pin) 108. In a certain part of the base of the cylinder 11R, which corresponds to the connecting part between one end of the connecting rod 35 and the locking element 4 by means of a screw pin (screw pin) 108; a long groove 109, elongated in the transverse direction, is formed in such a way as to provide a linear reciprocating movement 4 of the locking element, which performs a linear reciprocating movement in the lateral direction in response to the expansion and compression of the thread control cylinder 32.

The connection of the end portion 35a to the other end of the connecting rod 35 connected to the expanded part 3c connected to the hook for hanging the threads 3 is bent down to a depth corresponding to the thickness of the expanded part 3c. The contact pin 110 protrudes upward from the connecting end portion 35a of the downward-curved connecting rod 35. On the other hand, the expanded portion 3c is provided with a connecting hole 111, which is mounted on top of the contact pin 110 and extends upward over the pin 110. This eliminates the need to perform a rigid connection operation of the connecting rod 35 and the extended part 3c, for example, being released from the state of mutual engagement between two loosened set screws or the like when the left side of the base of the needle plate 11L is removed from the platform of the sewing machine B by disconnecting it from the platform of the sewing machine B.

That is, the connecting hole 111 of the expanded portion 3c can be extended upward from the pin 110, and the blocking state between the connecting rod 35 and the expanded portion 3c (of the thread hanging hook 3) can only be released by raising the base of the left side of the needle plate 11L. In addition, when installing the base of the left side of the needle plate 11L to the platform of the sewing machine, only by moving the left side of the base of the needle plate 11L upward from the platform of the sewing machine B, the connecting hole 111 is worn on the pin 110 from above, thereby allowing the connecting rod 35 and the extended part 3c (hook hanging the thread 3) return to the locked state. The connecting end portion 35a of the connecting rod 35 need not be bent downward. That is, the connecting rod 35 may well be in the form of a flat plate.

The base of the attachment of the pivoting (swinging) lever (movable base) 92, which supports the pivoting (swinging) lever 9 of the locking mechanism so that it swings around the vertical support axis 90, is attached to the base of the cylinder 11R in order to provide a lateral adjustment position with using a long hole 93, elongated laterally, using the set screw 94. Thus, even after the base of the cylinder 11R is mounted in a locked state in the platform The shape of the sewing machine B using the screw element 107, the timing of the slipping of the looper 1 from the loop of the needle thread 20a held by the hook for hanging the thread 3 can be adjusted by laterally adjusting the position of the attachment base of the pivoting arm mount 92 relative to the base of the cylinder 11 R. This provides self-locking (self-looping), which provides prevention of the opening of the seam.

In a multi-thread chain stitch sewing machine with a horizontal cylindrical platform platform and with a seam opening prevention device Η having the above-described features, when a seam opening prevention device Η is installed in the sewing machine platform B, the left base of the needle plate 11L and the right base of the cylinder 11R, which obtained by dividing the base of the needle plate 11 into the right and left parts, can be individually attached to the platform of the sewing machine B. Therefore, in comparison with lzovaniem one long and large needle plate in case of technical solutions described in the previously filed application for patent by the present applicant, the attach operation (setting) of the entire device prevent Η suture unraveling with respect to the sewing machine platform B can be easily accomplished with less effort.

In addition, if after installing the base of the needle plate 11 (the left part of the base of the needle plate 11L and the right base of the cylinder 11R) in the platform of the sewing machine B, it becomes necessary to adjust the stitch to perform the sewing action by correcting the position and loci of movement of the components located below the base needle plate 11 and are located inside the platform of the sewing machine B, such as looper 1, and the elements of their drives, or it becomes necessary to carry out maintenance, for example, repair t and replacement of various types of components located below the base of the needle plate 11 and inside the platform of the sewing machine B, there is no need to remove the right base of the cylinder 11R, to which the thread control cylinder 32 and stopper cylinder 43 are connected, respectively having air pipes 33 and 43 attached to them and greatly interfering with their easy installation. A sufficiently wide working space can only be achieved by unscrewing and removing the left 11L part of the base of the needle plate from the platform of the sewing machine B.

Therefore, adjustment of sewing operations and maintenance, such as repair and replacement of various types of components located inside the platform of the sewing machine B, can be performed very easily, simply and efficiently only by operating with the small and light left part of the needle base of the plate 11L to which the air supply pipes 33 and 34 do not cling. Thus, satisfactory performance of the sewing function and the function of preventing the opening of the seam can be continuously demonstrated with excellent reproducibility, thereby allowing to solve the problems that remained unresolved in the patent application filed earlier by the present applicant.

In the present embodiment, a structure is used in which the pivoting (swinging) lever 9 in the locking mechanism is pushed by the action of the spring 91 in the direction in which the thread hanging hook in the needle thread support mechanism is in the standby (ready) position.

Thus, the action of the locking element 4 in the opposite direction (the action in the direction in which the hook hanging the thread is in the ready position) is due to the action of the force of the spring 9. This allows you to use the cylinder of one type of action as the cylinder of the stopper (stopper) 42 to bring in the action of the pivot arm 9, which engages with or disengages from part of the locking element 4, thereby achieving a reduction in size and lowering the cost of the cylinder of the stopper 42.

The present embodiment also uses a structure in which the needle thread control cylinder 32 and the stopper locking cylinder 42 are rigidly fixed to the lower surface of the mounting base of the cylinder 11R in a vertical two-stage fashion. In this way, the flat space occupied by the two cylinders 32 and 42 can be reduced for compactness and placement of the seam prevention device H, thereby allowing the seam prevention device размест to fit well inside the platform of the sewing machine B, compared to the case when the two cylinders 32 and 42 are located in separate positions (side-by-side arrangement), as is the case with the technical solution described in the previously filed patent application by the present applicant.

The present embodiment further utilizes the attachment structure of the looper thread holder 6 to the hook of the suspension of the thread 3 of the thread holding mechanism. The looper thread holder 6 holds the looper thread extending from the looper 1 to the fabric in a more forward position than the lower drop position of the needle 2 by swinging with the hook the suspension of the thread 3 in a plane almost parallel to the plane of the needle plate Ρ around the vertical support axis 30 between the gripping position threads, hold position and wait position. This simple design makes it possible to reliably position the looper thread 10 together with the needle thread 20. Thus, the loop self-locking (self-looping) can be confidently performed to further ensure the effect of preventing the seam from blooming.

In particular, relative to the position of the movable holder of the looper thread holder 6 with respect to the hanging hook of the thread 3, the relative position of the needle thread 20 and the looper thread 10 can be appropriately set, and self-locking (self-looping (self-looping)) can be reliably performed to further enhance the prevention effect dissolving the seam. [0102]

The present embodiment further utilizes a design in which the pin 110 projects upward from the connecting end portion of the connecting rod 35a of the connecting rod 35, and the connecting hole 111 is put on the pin 110 from above, thereby forming the end connecting portion (the expanded portion 3c is closer to the hook for hanging the thread 3 Therefore, when the left side of the base of the needle plate 11L is detached and pulled upward from the platform of the sewing machine B to adjust the stitch and service being performed, for example, such as nta and replacement of various types of components located in the platform of the sewing machine B, the hook for hanging the threads 3 and the connecting rod 35 can be disconnected from each other only by lifting the left part of the base of the needle plate 11L without performing laborious operations such as loosening and removing the screw connecting the connecting rod 35 and the extended portion 3c is closer to the hook for hanging the threads 3, or by removing the connecting pin.

In addition, after adjustment and maintenance, the hanging hook of the thread 3 and the connecting rod 35 can only be returned to the set connection state by attaching the left side of the base of the needle plate 11L to the platform of the sewing machine B from above. This additionally saves setup and maintenance work.

Although an embodiment of the invention has been described using pneumatic cylinders as hook and stop actuators, electromagnetic solenoids can also be used as actuators.

Although the case described above also describes the formation of a multi-thread seam of a chain stitch with two needles 20 and 20 and one thread of a looper 10, this applies to a seam that is formed by several needles forming a seam of a double chain stitch using three or more needle threads, or one that forms a single-needle seam of a chain stitch with a single thread, or a sewing machine with a multi-thread chain stitch to sew surface seams of a chain stitch.

The above option also relates to the case of preventing the opening of the seam in which one of the loops of the needle thread formed by the two needle threads 20 and 20 is caught and held in the holding position, and in this state, a sewing action is performed to make one stitch for self-locking (self-looping) . In addition, a plurality of loops of needle threads can be caught and held in the holding position, and sewing actions in the holding state can be performed on two or more stitches without being limited to one stitch.

In the above embodiment, the invention also includes the case where the looper thread holder 6 of the suspension hook of the needle thread holding mechanism (needle thread holder mechanism) is preferably provided with a looper thread holder that holds the looper threads exiting the looper in a more forward position compared to the lower position the needles by swinging together with the hook hanging the threads around the support shaft in a plane essentially parallel to the needle plate between the position of the grip, laying down hold and waiting position. In addition, the looper holder 6 and the thread hook 3 can be individually arranged and individually controlled by dedicated drives other than the thread control cylinder 32 to operate the thread hook 3. In addition, it is not necessary to install the looper thread holder 6 .

Industrial applicability

The base of the needle plate is divided into left and right sections, which are made with the possibility of individual installation in the form of the left supporting part of the base of the needle platinum and the right base of the cylinder. Thus, the attachment (installation) of the device to prevent the opening of the seam in the platform of the sewing machine and the adjustment of the sewing actions and maintenance and repair and replacement of various types of components located inside the platform of the sewing machine can be easily carried out at lower labor costs, which allows it to be considered A convenient application to multi-thread chain stitch sewing machines.

Bibliography

1. Japanese Patent Application No. 2011-016821.

2. Japanese Patent Application No. 2011 -115174.

Claims (16)

1. Sewing machine multi-thread chain stitch with a device to prevent the opening of the seam, containing a needle moving up and down, holding the needle thread; the looper holding the looper thread, with the possibility of moving forward and backward in a direction substantially orthogonal to the vertical path of the needle, and catching the loop of the needle thread formed by the needle while moving forward below the needle plate; and the base of the needle plate, with the needle plate attached to it and attached to the upper surface of the platform of the sewing machine; with the possibility of forming a multi-thread chain stitch on the seam fabric resulting from the looper catching a needle thread loop formed by a needle under the needle plate, followed by mutual engagement of the needle thread with the looper thread supported by the looper, characterized in that it contains:
a thread suspension mechanism including a hook capable of approaching and deflecting with respect to the looper, and swinging in a plane substantially parallel to the needle plate, around a vertically arranged support shaft, between the standby position away from the looper and the position of capture of the thread close to the looper; a hook drive for controlled swing of the hook hanging the thread between the standby position and the grip position of the thread;
a locking mechanism comprising a locking element and a locking element drive, wherein the locking element is located much further from the needle plate than the hook for hanging the thread of the thread holder mechanism, and allows the suspension and resumption of swinging of the thread hanging hook from the gripping position to the standby position so that the loop the needle thread caught by the thread of the hook hanging the thread in the grip position of the thread was in a holding position between the grip position of the thread and the standby position;
and a stopper drive for suspending and resuming movement of the stopper element;
a connecting element for connecting with the mutual engagement of the hook hanging the thread of the needle needle holder of the thread and the locking element of the locking mechanism; and
a control unit that controls the needle thread holder and the locking mechanism, combining the vertical movement of the needle, the looper forwards and backwards and the fabric feed, so that the looper moves forward after stopping normal sewing, the hook for hanging the thread of the needle thread holder mechanism is brought to a position near the looper, and the loop of the needle thread caught in the grip position of the thread moves to the holding position, and the resulting position is maintained until the needle drops through the needle thread caught in the looper, thus stitching in the volume of at least one sewing stitch, the base of the needle plate being divided into two parts, the left and right support bases, of which the left part is used to attach the needle plate to it and supporting the swinging support shaft of the hook for hanging the thread, and the right side of the needle plate is for rigidly fastening the locking element, the hook drive and the stopper drive, while the right side of the base of the needle plate is attached to the joint platform machine, and the left part of the base of the needle plate is attached to the upper surface of the platform of the sewing machine using screw elements with the possibility of removal and reinstallation. 2. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the fabric feed mechanism has the ability to reduce the fabric feed speed compared to the normal sewing speed by command of the control unit during the sewing operation in at least one stitch. 3. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the looper is equipped with a thread tensioner mechanism for holding back the looper thread to the looper at the command of the control unit, after which the looper thread is located in front of or behind the lower needle position. 4. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the locking mechanism is further provided with:
a locking element that is directly connected to the hook drive and has the ability to move relative to it linearly;
a rotary lever with the possibility of engagement and disengagement with part of the locking element;
a spring for initiating the swing of the pivot arm in the direction in which the hook for hanging the thread is in the ready position, and a stopper drive for disengaging the pivot arm from a part of the stopper element to overcome the spring force. 5. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the pivot arm in the locking mechanism is attached laterally to the movable base, which in turn is attached laterally to the right side of the base of the needle plate. 6. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the hook drive of the needle thread holder mechanism of the needle thread and the stopper of the stopper mechanism can be rigidly mounted vertically in two positions on the lower surface of the right side of the base of the needle plate. 7. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that it further comprises a looper thread holder that supports the looper thread extending from the looper to the fabric in a position further than the lower needle position due to joint swaying with a hook for suspending the thread of the needle thread thread holder mechanism around the support shaft in a plane substantially parallel to the needle plate, between the thread gripping position, the holding position and the waiting position; and a drive for swinging the looper thread holder. 8. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the looper thread holder is attached together with a hook for hanging the thread of the thread holder mechanism so as to swing along with the hook for hanging the thread around the support shaft in a plane substantially parallel the plane of the needle plate, between the position of the capture thread, the hold position and the standby position. 9. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 8, characterized in that the looper holder is attached in a movable position to the thread hanging hook. 10. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the hook drive of the needle thread holder mechanism and the stopper of the stopper mechanism are made in the form of pneumatic cylinders. 11. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the pin protrudes upward from the end of the connecting part of the connecting element and the end part of the connection of the thread hanging hook is made with a connecting hole that is put on the contact pin from above and removed in the opposite direction. 12. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that the left side of the base of the needle plate or platform of the sewing machine is provided with protruding pins to position the left side of the base of the needle plate of the sewing machine on the platform in a variety of positions away from many rigidly attached connecting parts and the connection is partially disconnected due to the screw elements, and the platform of the sewing machine or the left side of the base of the needle plate s are provided with holes to engage with pins. 13. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that a single-needle cylindrical horizontal multi-thread chain stitch sewing machine is used as a sewing machine. 14. A multi-thread chain stitch sewing machine with a seam opening prevention device according to claim 1, characterized in that a multi-needle cylindrical horizontal multi-thread chain stitch sewing machine is used as a sewing machine.
However, in a multi-thread chain stitch sewing machine with a seam opening prevention device, the following problems remained unresolved.
Thus, in the technical solution described in the already filed patent application of the applicant of the present invention, as shown in FIG. 21-23, the hanging hook of the thread 3, the stopper lever 4, the pivoting lever 9, the thread control cylinder 32, the stopper cylinder 42 are structural elements supported laterally by a long and large base of the needle plate 11, which includes a needle plate P connected and fixed on the upper surface of the platform of the sewing machine. In particular, the reference axis 30 of the swing of the thread of the hook hanging the thread, 3 is supported in a position in the immediate vicinity of the back of the needle plate Ñ on the left side of the base of the needle plate 11. On the other hand, the stopper lever 4, the pivot lever 9, the thread control cylinder 32 , and the stopper cylinder 42, respectively, are supported in a position away from the needle plate Ñ on the right side relative to the base of the needle plate 11. In addition, a connecting rod (connecting rod) 35 connected between the front end part of the turn of the lever 9 and the front end part of the expanded part 3c, expanded (passes) so as to fold forward from the support shaft 30 to swing the hook hanging the thread 3. By number 6 in FIG. 21-23, the looper thread holder is marked, fastened together with the hook for hanging the thread, 3 with the fixing screws 60 and 60.
Thus, in the multi-thread chain stitch sewing machine described in the previously filed patent application by the present applicant, all structural elements of the seam opening prevention device are supported in the direction transverse to the long and large base of the needle plate 11. Therefore, if after the base of the needle plate 11 with the components of the device for preventing the opening of the seam installed and fixed on the upper surface of the platform of the sewing machine, it becomes necessary to adjust, for example, the stitch by correcting the position and loci (location, hodograph) of the elements performing the sewing action, which are located below the base of the needle plate 11 and inside the platform of the sewing machine, such as a looper and elements that activate it, or if it becomes necessary to carry out maintenance, for example, by replacing the various types of components included in the platform of the sewing machine, a wide working space sufficient to perform adjustment and maintenance cannot be ensured It is possible only by removing the needle plate P. Therefore, in order to provide the wide working space necessary for performing the operation, for setting and maintenance, it is necessary to completely temporarily remove the long and large base of the needle plate 11 from the platform of the sewing machine, after which the base of the needle plate 11 is installed in place in the platform of the sewing machine.
In particular, the air pipes 33 and 43 for supplying working air to the thread control cylinder (pneumatic cylinder) 32 and the stopper cylinder 42, respectively, are connected to these two cylinders. Thus, to perform an extremely troublesome and time-consuming operation, in which, when removing and attaching the base of the needle plate 11, these two air tubes 33 and 43 are pulled from the inside of the platform of the sewing machine, and it is necessary that both of them do not interfere with the removal and installation operations in addition, after these operations, the air tubes are pushed back into the interior of the platform of the sewing machine. However, even if, despite the troublesome and time-consuming task, the adjustment and maintenance operations are still carried out, there is a possibility that after all this, the stitching has worsened, and the function to prevent the opening of the seam cannot be reproduced. The elimination of this will require again troublesome and time-consuming operations, which suggests that the problem remains unresolved.
SUMMARY OF THE INVENTION
The present invention was created due to the foregoing circumstances, and its object is to provide a multi-thread chain stitch sewing machine with a seam opening prevention device, by which the seam opening characteristic of multi-thread chain stitch seams can be effectively prevented, and it is very easy and simple to carry out maintenance such how to adjust the stitch by correcting the position of the elements involved in sewing, and replacing various types of components inside the seam platform machine without any problems and labor and time, allowing to achieve the prevention of opening of the seam and the constant reproduction of this function.
To achieve the above goal, a multi-thread chain stitch machine with a seam opening preventer in accordance with the present invention includes: a needle moving up and down holding a needle thread; a looper that can move back and forth while holding the looper thread in a direction substantially orthogonal to the vertical path of movement of the needle, and which catches the loop of thread formed below the needle plate with the needle while moving forward; and the base of the needle plate, including the base of the needle plate with a needle plate attached thereto, and it itself is attached to the upper surface of the platform of the sewing machine.
The multi-thread chain stitch machine forms seams of the multi-thread chain stitch on the fabric, allowing the looper to catch the needle thread loop formed below the needle plate by the needle, and then intercept (re-hook) the needle thread with the looper thread. very easy and simple, the thread of a multi-thread chain stitch with a device for preventing the opening of a seam includes: (A) a needle thread holder mechanism, which has (I) a thread suspension hook that can approach and move away from the looper and swing around a vertically support shaft in a plane almost parallel to the needle plate between the standby position away from the looper and the grip position of the thread close to the looper, and (II) the thread hook hook (hanging thread) to swing the hook to the o position fluid and clinging position of the thread; (B) a locking mechanism (III) comprising a locking element that is located farther from the needle plate than the hook, hanging the thread, the thread holding mechanism, and allows temporarily suspending and resuming swinging of the thread hanging hook, from the gripping position to the ready position so that the loop of the needle thread caught by the hook hanging the thread in the grip position of the thread remained in the holding position between the grip position of the thread and the standby position; and (IV) a stopper drive for holding and releasing the stopper element; (C) a connecting member for interlocking the thread of the hook hanging the thread, the thread holding mechanism, and the locking member of the locking mechanism; and (D) a control unit that controls the thread holding mechanism (needle thread holder mechanism) and the locking mechanism in combination with vertical needle movement, looper movement forward and backward, and fabric feed, so that the looper moves forward after normal sewing is finished, the hook hanging the thread, the thread holding mechanism, is carried near the looper, the loop of the needle thread captured in the grip position of the thread moves to the holding position, the resulting state is maintained until the loop of the needle thread It doesn’t go down through the loop of the thread caught by the looper, and after that, the sewing action for at least one stitch is considered to be completed.
The base of the needle plate is divided into two parts: the left support base of the needle platinum (left base) for attaching the needle plate to it and maintaining the rotary support shaft of the hook hanging the thread; and the right base of the needle plate for motionless support of the locking element, the hook drive and the stopper drive. The right base of the needle plate is attached to the platform of the sewing machine. The left base of the needle plate is mounted-removable and attached to the upper surface of the platform of the sewing machine using screw elements.
In a multi-thread chain stitch sewing machine with a seam opening prevention device having the above characteristic features, after stopping normal sewing, the looper moves forward, and the needle hook of the needle thread holding mechanism of the needle thread is carried near the looper, and the needle thread loop caught by the looper moves to the holding position, and in this condition, a sewing action in the amount of at least one stitch is considered completed. Accordingly, the previous loop of the needle thread is self-gripping by the needle loop carried by the falling needle, and the looper thread is held below the self-locking portion of the loop, thereby preventing slipping of the looper thread. That is, the opening of the seam can be reliably prevented even in the developmental stage.
In addition, in the present invention, the base of the needle plate attached to the platform of the sewing machine is divided into two parts: the left side of the base of the needle plate for attaching the needle plate to it and with the possibility of mounting the rotary support shaft of the hook hanging the thread, the needle thread holding mechanism; and the right side of the base of the needle plate for rigidly fastening the stopper element of the stop mechanism, the hook drive and the stopper drive. Thus, compared with the use of one long and large needle plate, as in the case of the machine described in the previously filed patent application of the present applicant, the attachment (installation) of the device to prevent the seam from opening to the platform of the sewing machine can be easily carried out with less effort, since the left and the right side of the base of the needle plate can be individually attached to the platform of the sewing machine, and the seam opening prevention device can be mounted to the platform of the sewing machine s.
Moreover, if after the seam opening prevention device is mounted on the platform of the sewing machine, it becomes necessary to adjust the stitch by correcting the position and movement of the components to perform the sewing action, those located below the base of the needle plate and inside the platform of the sewing machine, such as the looper and looper drive elements, or if it is necessary to carry out maintenance, such as repairing or replacing various types of components, located below the base of the needle plate or inside the platform of the sewing machine, it will be necessary to remove the right side of the base of the needle plate with a solid attachment of the hook drive and the stopper drive to which the air pipes or electric power supply line are connected, however, a sufficiently wide working space can be provided by detaching and removing only the left side of the base of the needle plate from the platform of the sewing machine.
Thus, seam adjustment and maintenance, such as repairing and replacing various types of components located in the platform of the sewing machine, can be done very easily, simply and efficiently by manipulating the small and light left side of the base of the needle plate with which no feed tube air, no power line connected. This creates the effect that sewing is satisfactorily carried out and the preventive function of preventing the opening of the seam can be regularly performed with excellent reproducibility, thereby ensuring success in solving the problem that remains unresolved in the previously filed patent application of the present applicant.
In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the locking mechanism preferably includes: a locking element that is directly connected to the hook drive and moves linearly with respect to it; the pivot arm engages with and disengages from a part of the locking member; a spring for exciting the swing of the pivot arm in the direction in which the hook for hanging the thread is in the ready position; and a stopper drive for disengaging the pivot arm from a portion of the stopper member as a result of counteracting the force of the spring.
In this case, the action of the locking element in the opposite direction (action in the direction in which the hook hanging the thread is in the ready position) is carried out as a result of the excitation of the spring force. Thus, a stop actuator for actuating a pivot arm that engages with or disengages from a portion of the retainer element may be capable of pushing to control the retainer element. Therefore, the use of a pneumatic cylinder as a stopper drive allows the use of a single-acting type air cylinder, thereby achieving a reduction in size and lowering the cost of the stopper drive.
In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the pivoting (swinging) lever in the locking mechanism is preferably attached to a movable base attached laterally to adjust the right side of the base of the needle plate. In this case, lateral adjustment of the position of the movable base relative to the right side of the base of the needle plate, coordination of the time interval during which the looper leaves the loop of the needle thread supported by the hook hanging the thread can be easily and appropriately adjusted to verify the implementation of self-locking to prevent the seam from opening .
In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the thread hook of the thread holding mechanism and the stopper of the stopper mechanism are preferably firmly mounted vertically on-off (two-stage) on the lower surface of the right side of the base of the needle plate.
In this case, two drives are rigidly mounted on the right side of the base of the needle plate vertically in a two-position (two-stage) way, and, therefore, the flat space occupied by these two drives can be reduced for compactness, which allows them to be well located inside the platform of the sewing machine, compared to case when two drives are located in places separated from each other (side-by-side location) as in the case of the solution described in the previously filed patent application of the present applicant.
In a multi-thread chain stitch sewing machine with a seam opening prevention apparatus according to the present invention, the thread hook of the thread holding mechanism is preferably provided with a looper thread holder that holds the looper thread exiting the looper into the fabric in a more advanced position than the lower needle position by swinging together with the hook hanging the threads of the needle thread holding mechanism around the support shaft in a plane substantially parallel to the needle plate between the locking position vata thread, hold position, and wait position.
In this case, the looper thread is held in position in front of the lower needle position by the looper thread holder, which interacts with the hook for hanging the thread. This simple design allows the looper thread to accurately position itself with the needle thread. Accordingly, self-locking (self-locking) can be reliably performed in order to more reliably prevent the seam from opening.
In a multi-thread chain stitch sewing machine with a seam opening prevention apparatus according to the present invention, the looper thread holder is preferably attached in an adjustable position to the thread hanging hook. In this case, the relative position between the needle and the looper thread can be correctly set, and self-locking (self-locking) can be performed more reliably to further increase the prophylaxis of the effect of the dissolution of the seam.
In a multi-thread chain stitch sewing machine with a seam opening prevention device in accordance with the present invention, the needle thread holding mechanism hook drive and the stopper (stop) mechanism stopper drive are preferably both in the form of pneumatic (air) cylinders (hereinafter referred to as cylinders).
In this case, the thread hanging hook in the needle thread holding mechanism and the pivot arm in the locking mechanism can operate with high speed based on a control signal from the control unit, thereby providing a reliable and effective preventive effect of preventing the seam from opening after normal sewing.
Instead of cylinders, electromagnetic solenoids or similar devices can be used as drives.
In a multi-thread chain stitch sewing machine with a seam opening prevention device according to the present invention, it is preferable that the pin protrudes upward from the end of the connecting part of the connecting element, and part of the connecting end of the thread hanging hook is preferably provided with a connecting hole that can be worn on top of the contact pin directed up.
In this case, when the left part of the base of the needle plate is removed from the platform of the sewing machine in the upward direction as a result of detaching it from the upper surface of the platform of the sewing machine to perform maintenance such as repair and replacement of various components placed inside the platform of the sewing machine, the connection between the hook hanging the thread and the connecting element can only be released by raising the left side of the base of the needle plate, without requiring any onerous operations, so x as a detachment and extraction screw, which the connection to the connecting member and the hook hanging or stretch yarn connecting pin. In addition, after adjustment and maintenance, the thread hanging hook and the connecting element can only be returned to the set connection state by firmly attaching the left side of the base of the needle plate to the platform of the sewing machine from above. This saves even more time and labor during adjustment and maintenance.
In a multi-thread chain stitch sewing machine with a seam prevention device according to the present invention, the left side of the base of the needle plate or platform of the sewing machine is preferably provided with: protruding pins for positioning the left side of the base of the needle plate on the platform of the sewing machine in a plurality of positions apart from the set connected parts and parts of the separation-connection by means of screw elements, and the platform of the sewing machine or the left side of the base needle The plate is preferably provided with pin holes for engaging with pins.
In this case, when the left side of the base of the needle plate is attached and detached from the platform of the sewing machine, the left side of the base of the needle plate can, of course, be located in a predetermined position on the platform of the sewing machine due to the contact between the plurality of pins and pin holes. Therefore, even when the left side of the base of the needle plate is reconnected and disconnected from the platform of the sewing machine, each time adjustment and maintenance is performed, the left side of the base of the needle plate can be attached to the platform of the sewing machine in a constantly set position and orientation. Therefore, in addition to ordinary sewing, the preventive function of preventing the seam from opening can also be constantly carried out and absolutely reproduced.
The seam opening prevention apparatus according to the present invention is accordingly applicable to a horizontal cylindrical platform type of a multi-thread chain stitch sewing machine.
Brief Description of the Drawings
The invention is illustrated by the figures of drawings (schemes) 1-23, for the understanding of which the following notation is used: List of notation indicated in the figures: 1 - looper; 2 - needles; 4 - locking element; 3 - hook hanging the thread; 6 - looper thread holder; 8 - control unit; 9 - rotary (swinging) lever; 10 - looper; 11 - the base of the needle plate; 11L - left support base of the needle plate; 11R bases for attaching the cylinder (right base of the needle plate); 20 - needle thread; 20a, 20b loop of threads; 30 - vertically protruding support axis; 32 - thread control cylinder (hook drive); 35 - connecting rod (connecting element); 42 - cylinder stopper (limiter) (drive stopper); 91 - spring; 92 - the base of the mounting of the rotary (swinging) lever (moving base); 102 - screw elements; 103 - pin; 104 - hole for the pin; 110 - pin; 111 - connecting hole; A - extreme lower position of the needle; In - a platform of the sewing machine; Ñ - needle plate; Ì - multi-thread stitch of a chain stitch.
FIG. 1 is a perspective view of a multi-thread chain stitch sewing machine with a horizontal-type cylindrical-platform seam opening preventer in accordance with an embodiment of the present invention.
FIG. 2 shows a perspective view illustrating the structure of the main seam parts of the seam opening prevention apparatus in a multi-thread chain stitch sewing machine with a horizontal type cylindrical platform.
FIG. 3 is a perspective view showing a state in which a part of the structure of the main part of the seam anti-swell prevention device is removed.
FIG. 4 is a plan view showing a structure of a main part of a seam opening prevention apparatus.
FIG. 5 is a bottom plan view showing the main parts for explaining the structure of the locking mechanism and its first action in the seam opening prevention device.
FIG. 6 is a bottom view explaining the structure of the locking mechanism and its second action.
FIG. 7 is a bottom view explaining the structure of the locking mechanism and its third action.
FIG. 8 is a bottom view explaining the structure of the locking mechanism and its fourth action.
FIG. 9 is a block diagram showing a configuration of a control system of a multi-chain chain stitch sewing machine with a horizontal cylindrical platform with a seam opening prevention device.
FIG. 10 is a timing chart explaining a content of an operation of a control unit in a seam opening prevention device;
FIG. 11 provides an explanation of the first action of the seam opening preventive prevention device.
FIG. 12 provides an explanation of the second action of the seam opening preventive prevention device.
FIG. 13 provides an explanation of the third action of the seam opening preventive prevention device.
FIG. 14 provides an explanation of the fourth action of the seam opening preventive prevention device.
FIG. 15 provides an explanation of the fifth action of the seam opening preventive prevention device.
FIG. 16 provides an explanation of the sixth action of the seam opening preventive prevention device.
FIG. 17 provides an explanation of the seventh action of the seam opening preventive prevention device.
FIG. 18 is a view of a seam structure of two needle sewing machine of a multi-thread chain stitch obtained by the present invention, as viewed from the back of the fabric;
FIG. 19 is an explanatory drawing for preventing blooming of the seam structure shown in FIG. eighteen.
FIG. 20 is a view of the overall design of the seam in the area at the end of sewing, as viewed from the back of the fabric
FIG. 21 is a plan view, approximately, showing the structure of the main parts of the weld prevention device working according to the technical solution described in the previously filed patent application of the present applicant;
FIG. 22 is a bottom view, approximately showing the structure of the main parts of the device for preventing the opening of the seam working according to the technical solution described in the previously filed patent application of the present applicant.
FIG. 23 is a plan view explaining the effect and condition of the main parts of the joint opening prevention apparatus operating in accordance with the technical solution described in the previously filed patent application of the present applicant.
The implementation of the invention
One embodiment of the present invention is described below with reference to the accompanying drawings.
In FIG. 1 shows a general view of a multi-thread chain stitch sewing machine with a horizontal type cylindrical platform in accordance with an embodiment of the present invention. FIG. 2 and 3 show the structure of the main parts of the seam opening prevention device in the construction of a multi-thread chain stitch sewing machine with a horizontal type cylindrical platform in accordance with the present invention. FIG. 4 is a plan view showing the structure of the main parts of the weld prevention device. Further description is made using the terms “left,” “right,” “forward,” and “backward,” indicated by arrows in FIG. 2-4. The term “forward” means the side next to the sewing operator. The term “back” refers to the side away from the sewing operator. The terms “left” and “right” mean left and right when viewed from the front from the side of the sewing operator.
In the present embodiment, structural elements and structural parts identical or corresponding to the technical solution described in the previously filed patent application of the applicant of the present invention described with reference to FIG. 21-23 using the same reference numerals.
As shown in FIG. 1, in a multi-chain chain stitch sewing machine with a horizontal cylindrical platform in accordance with the present embodiment of the present invention, the shoulder of the sewing machine C and the platform of the sewing machine B are elongated almost horizontally to the left from the upper position and lower position of the body part D, respectively. As shown in FIG. 4, the multi-thread chain stitch sewing machine with a horizontal cylindrical platform includes: looper 1, two needles 2 and 2 (see Fig. 11-17), the base of the needle plate 11 attached to the upper surface of the platform of the sewing machine B, prevention device a dissolving seam Ç is embedded in the base of the needle plate 11, and the needle plate Ñ is fixed to the base of the needle plate 11. The needles 2 and 2 are moved up and down by the needle bar drive mechanism. The letters A and A in FIG. 2 and 4 indicate the lower needle positions (needle lowering positions) 2 and 2, respectively. The lower positions of the needles A and A are set on the sides at a distance and inside the middle part of the needle plate R. Looper 1 moves forward and backward (to the left - movement forward and to the right - movement in the opposite direction) due to the action of the looper drive mechanism. The solid line in FIG. 4 indicates the state in which looper 1 has moved to the left front position, and the dashed line in FIG. 4 indicates the state in which looper 1 has moved to the right rear position. As shown by the solid line in FIG. 4, the front end portion of the looper 1 in the left front position extends to the left of the positions of the needles A and A. As shown by the dashed line in FIG. 4, the front end of the looper 1 in the right rear position is to the right of the positions of the needles A and A.
A multi-thread chain stitch sewing machine with a horizontal cylindrical platform sews a fabric (not shown) located on the needle plate P as a result of the movement of the needles 2 and 2 up and down and the movements of the looper 1 left forward and right back. The fabric is pressed against the needle plate Ñ with a foot (not shown), and fed in the direction indicated by arrow Õ in FIG. 4 as a result of the action of the fabric feed mechanism installed inside the platform of the sewing machine B. The feed mechanism includes a conveyor that repeats such movements in which the gear rack, protruding from the needle plate P, moves in the opposite direction and moves in the forward direction when immersed under the needle plate P. The fabric is periodically fed to the conveyor in the direction of the arrow Õ.
The aforementioned needle bar drive mechanism, looper drive mechanism, and fabric feed mechanism are well-known mechanisms that work together synchronously mutually due to the energy coming from the spindle of a sewing machine (not shown). The needles 2 and 2 respectively hold the needle threads 20 and 20 (see Figs. 11-17), pass through the fabric and reach a position below the needle plate Ñ during a break in the supply of fabric, after which these needles move up and pass through the fabric in the direction up. The looper 1 holds the thread of the looper 10 (see Fig. 11-17), and moves to the left at the same time as the needles 2 and 2 begin to move upward, thereby catching the loops 20a and 20b of the threads of the needles 20 and 20, which are formed below needle plate R. The fabric is fed when the needles 2 and 2 move up. Needles 2 and 2 move downward when passing through the feed fabric, and catch the thread of looper 10, supported by looper 1 stretched to the right. The multi-thread chain stitch sewing machine forms a multi-thread chain stitch on the fabric, repeating the above steps.
The device for preventing the opening of the seam H, included in the design of the multi-thread chain stitch sewing machine described above with a horizontal cylindrical platform, includes: a thread holding mechanism, a locking mechanism, a connecting rod 35 as a connecting element for interlocking the hook for hanging the thread 3 (described below) with a thread holding a mechanism; locking element 4 (described below) of the locking mechanism; and control unit 8 (described below).
The thread holding mechanism includes a thread hanging hook 3, a cylinder controlling the reciprocating movement of the thread 32 in the form of a hook drive for controlling the swing of the thread hanging hook 3 around a vertical protruding support axis 30 between the standby position away from looper 1 and the engagement position next to the looper 1. The support axis 30 as the center of swing of the hook for hanging the thread 3 is located in close proximity to the right angle of the back side of the needle plate Ñ and is fixed to the base of the needle plate eleven.
The hook for hanging the thread 3 has an arcuate curved shape and continuously takes shape so as to be folded in the direction of the front end of the support arm 3E protruding from the left end of the support axis 30. The front end of the hook for hanging the thread 3 is facing the lower position of the needles A and A c the left end of the lower side of the needle plate P. The protruding portion of the hook 3b is formed at the front of the end of the hook hanging the threads 3. The support arm 3e has an extended portion 3c, protruding forward from the support axis 30, and one to the end of the connecting rod 35 is connected to the front end portion of the protruding portion 3c.
As shown in FIG. 4, the looper thread holder 6, having an arcuate curved shape, is fastened together with the base part of the thread hanging hook 3 with two fixing screws 60 and 60. The front end part of the looper thread holder 6 projects forward substantially along the left side of the thread hanging hook 3 and collides into the lower the position of the needles A and A with the front position of the front of the end of the hook hanging the threads 3. The receiving part of the looper thread 6a branched into two parts is formed on the front end part of the looper thread holder 6. Thread holder etlitelya 6 allows adjustment position relative to the hook suspension string 3 by turning the fastening screws 60 and 60. Tilt provides retention looper 10 of the looper thread receiving portion 6a on the front end.
As shown in FIG. 5-8, the locking mechanism includes a locking element 4, which is attached to the front end part (left end part) of the output shaft 31 of the cylinder 32 controlling the thread by means of a fixing screw 36 and can be mutually moved in a straight transverse direction due to expansion and contraction thread control cylinder 32 by supplying air through an air tube 33; a pivot arm 9 engaged with and disengaged with a part of the locking element 4; a spring 91, which allows the pivoting lever 9 to engage with a part of the locking element 4 and gives swing energy to it in the direction in which the hook for suspending the thread 3 is in the ready position; and a locking cylinder 42 of one type of action (pushing type in the left direction), as a locking actuator, which forcibly releases the pivot arm 9 from the side of the part of the locking element 4 against the action of the swing force by the spring 91.
The output rod 41 of the locking cylinder 42 is configured to swing the pivot arm 9 counterclockwise against the action of the oscillating force of the spring 91 because the stopper 42 is pushed to the cylinder drive in the left direction by the working air supplied through the air tube 43. The pivot arm 9 is attached by the upper surface of the pivot arm ( movable mounting) 92 so that it can swing around the center of the protruding vertical support axis 90. The pivot arm 9 has a claw gear 9a on the front end part for engaging with part of the locking member 4. As shown in FIG. 5, the pivot arm 9 contacts the lateral part of the locking element 4 due to the driving force of the spring 91 while the locking element 4, due to the driving force, moves to the left by expanding the stitch of the cylinder controlling the thread 32, that is, at a time when the hook for hanging the thread 3 moves to the standby position. As shown in FIG. 6, the pivoting (swinging) lever 9 moves clockwise around the support axis 90 as a result of the transfer of force from the spring 91, and the engaging claw 9a at its front end enters into a engaged state with a part of the locking element 4, while the locking element 4 is controllably moved to the right side due to the reduction of the cylinder controlling the thread 32.
As shown in FIG. 7, allowing the compressed thread control cylinder 32 to somehow resume compression, the engaging claw 9a at the front end of the swing arm 9 engages with a part of the locking element 4, thereby temporarily stopping the locking element 4 to the left, In a state in which 4 the locking element thus temporarily suspended (paused), the hanging hook of the thread 3 moves to the holding position between the standby position and the hooking position of the thread, and remains at the expense of the connecting rod 35. At this time, part of the hook 3b at the front end of the hook suspension string 3 moves from the yarn engagement position shown in FIG. 4 (between the lower positions of the right and left needles A and A) to the left rear of the lower position of the left needle A, and grabs the thread of the left needle 20 and holds it in the holding position. The looper thread holder 6 moves forward to the front of the looper 1, and the receiving part of the looper thread 6a at its front end holds the looper thread 10 in the most forward (advanced) position compared to the lower position of the left needle
Further, as shown in FIG. 8, the pivot arm 9 pivots (pivots) counterclockwise, counteracting the swing force of the spring 91, allowing the output rod 41 to be pushed to the left while expanding the stopper cylinder (limiter) 42. This swing allows the engaging claw 9a at the front end of the pivot (swing) arm 9 to detach from parts of the locking element 4, thereby releasing the temporary locking element 4 from the temporary suspension.
Therefore, the thread control cylinder 32 undergoes maximum expansion and the hook for hanging the threads 3 and the thread holder of the looper 6 are alternately returned to the standby position through the connecting rod 35.
As described above, in the present embodiment, the thread hanging hook 3 and the looper thread holder 6 of the needle thread holding mechanism rotates to the standby position, to the thread engaging position, and the holding position by expanding and contracting the thread control cylinder 32 and the stopper cylinder 42 .
A multi-thread chain stitch sewing machine with a horizontal cylindrical platform in an embodiment of the present invention further includes a thread cutting mechanism 5 for cutting the needle thread 20 and the looper thread 10 after the sewing action has been performed. As shown in FIG. 16 and 17, the thread trimming mechanism 5 includes: a cutting hook 50; thread cutting knife 51; a flat spring 59 for pressing the thread cutting hook 50 against the sliding contact part between it and the thread cutting knife 51; and a thread cutter drive 58 (see FIG. 9). The thread cutting hook 50 has at its front end portion a first hook part 51 and a second hook part 53 that protrude backward. The thread trimming mechanism 5 is well known, and therefore its description and illustrations of other design features are omitted here.
In FIG. 9 shows a block diagram of a configuration of a multi-thread chain stitch sewing machine control system with a horizontal type cylindrical platform with a seam opening prevention device H described above. The pedal depression signal 21a and the pedal 21b feedback signal generated by the pedal switch 21, the needle position signal 22 is generated when the needles 2 and 2 are in close proximity to the top dead center, the thread cut signal 23, and the thread break signal 24 are respectively input to the block control 8 sewing machine multi-thread chain stitch.
On the other hand, the control unit 8 provides control signals to the thread control cylinder 32, stopper cylinder 42 and thread cutter 58, respectively. The hanging hook of the thread 3 and the looper holder 6 operate as described above, in accordance with the action of the control signals from the control unit 8 to the thread control cylinder 32 and stopper cylinder 42, and the thread cutting drive 58 of the thread cutting mechanism (not shown) expands and is compressed in accordance with the thread cutting signal 23 coming from is output from the control unit 8. The control unit 8 also provides control signals for the action, respectively, of the motor (motor) of the sewing machine 80 as a spindle drive source sewing machine, presser foot cylinder 81 for moving up and down the presser foot for pressing the fabric, an air cleaner 82 for sliding (cleaning) the needle threads 20 and 20, the parts have been shortened as described previously, the fabric feed speed reduction mechanism 83 for adjusting the fabric feed rate, and a looper thread holding mechanism 84 to limit the supply of looper thread 10 to looper 1.
The tissue feed reduction mechanism 83 reduces the tissue feed rate by changing the operation mode of the conveyor in the tissue feed mechanism. For example, the time during which the conveyor acts on the fabric located on the needle plate P is reduced by deviating the passage of the tissue feed with respect to the needle plate Ñ in such a way as to shorten the time during which the mechanism protrudes above the needle plate P, or unit the pitch of the tissue feed mechanism decreases with a change in the length of the lever for cyclic operation of the tissue feed mechanism. The mechanism for reducing the feed rate of fabric 83 of this type is well known, and therefore, detailed illustrations and their description are omitted here.
The looper thread holding mechanism 84 comprises a thread tension disk for compressing the middle portion of the looper thread 10 for feeding into the looper 1 and an actuator that operates to increase or decrease the compression force of the looper thread by the thread tension disk. The compression force of the looper thread by the thread tension disc increases increases the resistance acting on the looper thread 10, thereby holding back the looper thread 10. The holding mechanism of this looper thread 84 is well known, and therefore, a detailed image and description thereof is omitted here.
In conclusion, the sewing machine for forming a multi-thread seam of a chain stitch has: a control unit 8, which prevents the opening of a multi-thread seam of a chain stitch, allowing the hook of hanging the threads 3 and the holder of the thread of the looper 6 to act synchronously with the motor of the sewing machine 80, presser cylinder 81, air cleaner 82 , a mechanism for reducing tissue feed rate 83, and a loop retention mechanism 84.
FIG. 10 gives a time chart showing the time and contents of the operation of the control unit 8 for the purpose of opening a multi-thread seam of a chain stitch. The control unit 8 is a computer, including a processor, ROM and RAM. Prevention of the opening of a multi-strand seam in accordance with the time pattern shown in FIG. 10, is performed as a result of a series of operations under the control of a processor in accordance with a program stored in ROM.
FIG. 11-17 are operation drawings of a multi-thread seam-preventing device Ç in a multi-thread chain stitch sewing machine with a horizontal cylindrical platform according to the present invention and showing the operating statuses of the thread, the hook for hanging the thread 3 and the thread holder of the looper 6, and the thread cutting hook when performing operations under control block 8 in accordance with the timing diagram of FIG. 10.
When the operator of sewing on the sewing machine stops normal sewing on the sewing machine, he stops the work by releasing the pedal of the sewing machine, and then the multi-thread chain stitch sewing machine with a horizontal cylindrical platform performs an operation to prevent the multi-thread seam from opening. In this case, the operator performs the work on the back of the pedal. A pedal switch 21 attached to the pedal outputs a pedal press signal 21a during a pedal press operation, and outputs a pedal signal back 21b in response to a reverse pedal operation.
When normal sewing is considered finished and the pedal for the sewing machine returns from the pressed state to the neutral state at the SI time in FIG. 10, namely, when neither the pedal 21a signal nor the pedal signal 21b is supplied from the pedal 21, the control unit 8 issues a stop command to the sewing machine 80, referring to the needle position signal received at the input.
Therefore, the machine is temporarily suspended in a state in which the needles 2 and 2 are located in close proximity to the top dead center, and the looper 1 moves to the left.
After that, the control unit 8 is on until the pedal is fed a signal operation backward. When the pedal back-off operation is performed, and the pedal back-off signal 21b is input at time S2 in FIG. 10, the control unit 8 starts operations to prevent the opening of the seam, as described below. When the signal for depressing the pedal 21a is supplied again from the pedal 21, the control unit 8 returns to normal sewing. Thus, the sewing operator can continue normal sewing by depressing the pedal again.
In FIG. 10 shows that although a neutral state is maintained for a period of time between S1 and S2, maintaining a neutral state is not necessary. The pedal at the end of normal sewing can be continuously transferred from the pedal depression state to the pedal reverse state. In this case, when passing through the neutral position by a shift, it enters a state of absence of a signal in which, in the absence of a signal for depressing the pedal 21a and in the absence of a return signal of the pedal 21b, a signal is generated. Using the no signal state as a trigger, the control unit 8 starts the operation to prevent the seam from opening after reaching the state in which the needles 2 and 2 rise almost to the top dead center and the looper 1 moves to the left, as described above.
Furthermore, during operation according to FIG. 10, although the pedal reverse operation at the time S2 continues during the operation of preventing the opening of the seam as described below, there is no need to continue the reverse operation of the pedal of stopping the operation of preventing the opening of the seam, and the operation of preventing the opening of the seam is continuously performed as a result of the operation of the control unit 8 even after the reverse signal of the pedal 21b is suspended.
FIG. 11 shows the states of the needle 2 and 2 and looper 1 at the beginning of the seam opening prevention operation. The needles 2 and 2 have passed and are now located above the fabric on which the seams of the multi-thread chain stitch M are located, formed by two needle threads 20 and 20 and the thread of the buttonhole 10. Buttonhole 1 has moved to the left under the fabric, and is in a state of capturing the buttonhole of the needle threads 20a and 20a respectively, formed by the needles 2 and 2. When the needle of the threads 20 and 20 and the thread of the looper 10 are cut in this state, the final part of sewing is formed as shown in FIG. twenty.
After starting the operation to prevent the opening of the seam, the control unit 8, firstly, provides a working command to the control cylinder thread 32 from the output side. In response to this command, the thread processing cylinder 32 moves from the expansion state shown in FIG. 5 to the compression state shown in FIG. 6, and the locking element moves to the right under the action of the drive.
Accordingly, the thread hanging hook 3 and the looper thread holder 6 are moved from the standby (standby) position to the gear engaged by swinging around the support axis 30 with the locking member 4 and the connecting rod 35. At this time, the hook portion 3b of the front end of the thread hanging hook 3 engages the loop the needle threads 20a on one side (left side) and the pivoting lever 9 of the locking mechanism swing clockwise around the support axis 90 under the influence of the force of the spring 91, and the engaging claw 9a at its front end enters the state of the hook fusion with part of the locking element 4.
Immediately after this, the control unit 8 sends a working command to the thread control cylinder 32. By executing the work command, the thread control cylinder 32 expands somewhat from the state shown in FIG. 6 to the state shown in FIG. 7, and the locking element 4 under the influence of the actuator moves linearly in the left direction. During a slight expansion of the thread control cylinder 32, the engaging claw 9a at the front end of the swing arm 9 engages with a part of the locking element 4, thereby temporarily stopping the movement of the locking element 4 to the left. In a state in which the locking movement element 4 is temporarily suspended, as shown in FIG. 12, the suspension hook of the thread 3 is moved by the connecting rod 35 to the holding position between the standby position and the grip position of the thread, and remains there and holds the thread loop of the left needle 20a in the holding position. The looper thread holder 6 moves toward the front of looper 1, and the looper part receiving the thread 6a at its front end holds the looper thread 10 in a more forward (advanced) position than the lower position of the left needle A.
After the hook for hanging the threads 3 and the holder of the threads of the looper 6, thus move and remain in the holding position, the control unit 8 gives the working commands respectively to the engine of the sewing machine 80, the mechanism for reducing the feed rate of the fabric 83 and the mechanism for holding the threads of the looper 84 at a time S3 (Fig. 10). These control commands are received, consistent with the signal of the position of the needle 22 during the period of time during which the needles 2 and 2 move down and again up to the position near the top dead center. As a result, a sewing action is performed on one stitch on the fabric. Sewing on one stitch is carried out at a lower feed rate than normal sewing action due to the action of the mechanism to reduce the feed rate of fabric 83. Sewing one stitch is also carried out under the action of the mechanism of holding the looper thread 84 in a state in which the feed of the looper 10 into the looper 1 is restrained . This improves the degree of tension (compression) of the thread of the looper 10 at the end of sewing, thereby increasing the effect of preventing the opening of the seam, described below.
As shown in FIG. 12, hanging the thread hook 3 and the looper holder 6 continues to hold the needle thread 20 and the looper thread 10 until the fabric feed is complete, the needles 2 and 2 pass through the fabric and move down, and the left needle 2 passes through the thread loop needle 20a held hook hanging thread 3 and catches the thread loop 20a. At this time, the looper thread 10 supported by the looper thread holder 6 is located in front of the left needle 2, as shown in FIG. 12. Thus, the left needle 2 does not capture the looper thread 10, and the looper thread 10 is simply caught behind the looper 2 with the right needle 2.
At the time when the left needle 2 catches the thread loop 20a, in particular at time point S4 in FIG. 10, the control unit 8 allows the cylinder of the stopper 42 to expand from the stopper mechanism by transmitting the operation command of the cylinder of the stopper 42. Accordingly, the output rod 41 is pushed to the left by the drive. Therefore, as shown in FIG. 8, the pivoting (swinging) lever 9 rotates counterclockwise against the oscillating force of the spring 91, and the engaging claw 9a at the front end of the tilt of the lever 9 disengages from a part of the locking element 4, which allows the temporarily held locking element 4. to be released. After the temporary holding is stopped stop element 4, the thread control cylinder 32 expands to its maximum at time S4. Therefore, as shown in FIG. 13, the hanging hook of the thread 3 and the looper thread holder 6 reverse the movement from the holding position to the standby position, swinging (turning) around the support axis 30 with the locking element 4 and the connecting rod 35, after which the loop of the needle thread 20a and the looper thread are released from holding 10.
After this, looper 1 performs the retraction action to the right, while the needles 2 and 2 are lowered and slides out of the grip of the caught needle threads 20a. After slipping out of looper 1, as shown in FIG. 14, the right needle 2 enters the state of catching the thread of the looper 10, similarly to what happens during normal sewing, while the left needle 2 enters the state of catching the loop of the thread of the left needle 20a.
In this state, looper 1 moves to forward forward to the left, and needles 2 and 2 go to upward movement. As shown in FIG. 15, the looper 1, which moves forward to the left, catches the loops of threads of the left and right needles 20a and 20b, and the needles 2 and 2, which move upward, pass through the fabric in an upward direction. Accordingly, the thread 20 caught by looper 1 intercepts the looper thread in the position of the right needle 2, while the thread 20 performs the so-called self-locking (self-looping), i.e., the previously formed loop of the needle thread 20a is captured by the upper thread 20 in the position of the left needle 2.
After the end of the sewing action in one stitch, in the state in which the needles 2 and 2 move up in close proximity to their top dead center, looper 1 is in the position of close proximity to the end of the movement to the left. After that, the control unit 8 is in the standby state until the thread trimming signal 23 is executed. Upon receipt of the thread trimming signal 23 at time point S5 in FIG. 10, the control unit 8 allows the thread trimming drive 58 of the thread trimming mechanism to perform a predetermined operation by feeding the thread trimming 58 to the thread trimming drive. Accordingly, the thread hanging hook 50 reaches the end of the forward movement along the upper part of looper 1, as shown in FIG. 16. At this time, the first part of the hook 52 at the front end of the thread cutting hook 50 passes through the loops of threads 20a and 20b held by the looper 1 at the left side of the looper thread 10 extending from the front end of the looper 1 to the fabric, and the second part of the hook 53 is opposite the threads of the left needle 20 on the left side of it.
Subsequently, the thread cutting hook 50 located in front of the movement moves to the right in the opposite direction. At this time, the first part of the hook 52 catches the looper thread 10 and the second part 53 of the hook, after which it catches two needle threads 20 and 20.
The looper thread 10 and the needle threads 20 and 20 caught in this way are then pulled toward the pulled end of the thread cutting hook 50, and cut, being brought into sliding contact with an edge portion at the front end of the thread cutting knife 51, as shown in FIG. 17. The end portion of the cutoff of the thread of the looper 10 is held in a sandwich mode between the crochet hook of the thread 50 and the leaf (flat) spring 59 in a position closer to the looper 1 than the trim position.
The loop retainer thread holding mechanism 84 continues to operate and exerts a predetermined tension force on the looper thread 10 extending from the front end of the looper 1 to the fabric until the above thread trimming operation is completed. This ensures that the first part of the hook 52 at the front end of the thread cutting hook 50 catches and cuts the non-free (pinched) thread of the looper 10.
After the trimming operation described above, the control unit 8 waits until it receives the thread removal signal (cleaning signal) 24. When the thread removal signal 24 arrives at time point C6 in FIG. 10, the control unit 8 permits the air of the cleaner 82 to be supplied by sending a control command to the cleaner 82. The cleaner 82 blows air and disconnects the ends of the needle threads 20 and 20 that exit from the needles 2 and 2. After that, the control unit 8 allows the presser foot cylinder 81 raise the presser foot for pressing the fabric by issuing a control command to the cylinder of the presser foot 81 at time C7 in FIG. 10, thereby completing the process of preventing the seam from blooming.
The above-mentioned sequence of operations for preventing the opening of the seam is carried out in a multi-thread chain stitch sewing machine Ì with a horizontal cylindrical platform, as shown in FIG. 18. As shown in FIG. 18, the looper thread 10 passes through the inner part of the right loop of the needle thread 20a (the seams. Are visible from the side of the lower (back) surface of the fabric in the left side of Fig. 18), finally forming a multi-thread chain stitch M, on the back surface of the fabric, and then returning to the position in front of the thread of the right needle 20, which passes through the bottom surface of the fabric during sewing in one stitch to prevent the seam from opening, and then is cut in a certain position after passing again through the inside of the loop of the right needle second thread 20a.
On the other hand, (on the right in FIG. 18), the left needle thread 20, which passes through the lower surface of the fabric during sewing, in one stitch to prevent opening, passes through the loop of the left needle thread 20b, finally formed on the lower surface of the fabric during normal sewing , and forms a chain stitch seam by self-locking the last loop of the left needle thread 20b, as described above. Therefore, as shown in FIG. 18, the looper thread 10 enters a clamping state between the left needle thread 20 and the last loop of the left needle thread 20b.
In FIG. 18, the last loop of the left needle thread 20b is shown in a loose (loose) state to illustrate the connection with the needle thread 20. However, as shown in FIG. 19, in fact, the last loop of the left needle thread 20b is tightly clamped after the thread 20 passes through it and is in the same state as the last loop of the right needle thread 20a. Then, when a part of the cut end of the looper thread 10 is pulled in the direction of the arrow, as shown in FIG. 19, the loop of the looper thread 10, passing in front of the right needle thread 20, is clamped and pulled into the last loop of the right needle thread 20a. As a result, the thread 20 enters a holding state between the thread of the looper 10 and the last loop of the right needle thread 20a, and the needle thread 20 and the thread of the looper 10 are knotted, as shown in FIG. 19. This node also provides resistance to the looper thread 10 and performs the function of preventing slipping from the looper thread 10.
Accordingly, in the state shown in FIG. 19, the left part of self-locking (self-looping) and the right knot are visible together in order to prevent the multi-thread seam of the chain stitch M from opening.
The features of a multi-thread chain stitch sewing machine with a seam-preventing device and a non-opening function are described in detail above, namely, an improved structure used in the present invention to solve a problem that remains unresolved in an already filed patent application of the applicant of the present invention is described below focusing on FIG. 2-4.
As shown in FIG. 2-4, the base of the needle plate 11 attached to the upper surface of the platform B of the sewing machine is divided into left and right parts of the base of the needle plate 11L and 11R. The left part of the base of the needle plate 11L contains a needle plate Ñ with the possibility of removal-attachment to its upper surface using the set screw 100, and also supports the support axis 30 as the axis of rotation (swing) of the hook hanging the thread 3 of the thread holding mechanism.
The threaded holes 101 are formed in a plurality on the front and back parts (two portions) in the immediate vicinity of the left end portion of the left base of the needle plate 11L, in particular in areas away from the point of attachment of the needle plate Ñ in close proximity to the front end (left edge ) sleeves of the sewing machine C, indicated by a conditional line in FIG. 4. The left part of the base of the needle plate 11L is attached to the upper surface of the platform B of the sewing machine so that it is possible to remove and install (screw-untwisting, mounting and dismounting).
Further, as shown in FIG. 3, the upper surface of the platform of the sewing machine B and the left side of the base of the needle plate 11L are provided with pins 103 and pinholes 104, to which the pins 103 fit, in positions away from the two mounting positions using a set of screw elements 102. In the pinholes 104 are inserted and the pins 103 are engaged from above, thereby positioning the left part of the base of the needle plate 11L in a predetermined position and position relative to the platform of the sewing machine B. In this state, the set of screw elements 102 are screwed into the threaded holes Stia 102, thereby allowing the left side of the base needle plate 11L to be attached against the top surface of the platform of the sewing machine B.
Although the present embodiment describes and illustrates one in which the pins 103 protrude upward from the upper surface of the platform of the sewing machine B, the holes 104 are formed on the left side of the base of the needle plate 11L, or, alternatively, the pins 103 can protrude downward from the lower surface of the left side of the base of the needle plates 11L, and holes 104 may be made in the upper surface of the platform of the sewing machine B.
On the other hand, the right side of the base of the needle plate 11R is a cylindrical base for attaching the thread control cylinder 32 and the locking cylinder 42 (hereinafter, the right side of the needle plate 11R is called the base of the cylinder mount). The above locking mechanism located in the lower part by the base of the cylinder 11R. More specifically, as shown in FIG. 5-8, the thread control cylinder 32 is rigidly fixed to the lower surface of the base of the cylinder 11R using the fixing screw 105. The lock cylinder 42 is located below the cylinder 32 of the thread control in a two-stage way (fashion), and the stopper cylinder 42 is rigidly mounted on the base of the cylinder 11R using the fixing screw 106.
The mounting base of the cylinder 11R is mounted in a “locked state” on the side surface of the platform of the sewing machine B using the set screw 107. The phrase “locked state” means a state in which the device to prevent the opening of the seam Ç is fixed in position by the fixing screw set 107 in installation it into the platform of the sewing machine B, and is fixed in a predetermined mounting position after installation without performing any positional adjustments or the like for ystvy.
One end (right edge) of the connecting rod (connecting rod) 35 is connected by a locking element 4 of the locking mechanism with the possibility of rotation by means of a contact screw (screw pin) 108. In a certain part of the mounting base of the cylinder 11R, which corresponds to the connecting part between one end of the connecting rod 35 and the locking element 4 by means of a screw pin (screw pin) 108; a long groove 109, elongated in the transverse direction, is formed in such a way as to provide a linear reciprocating movement 4 of the locking element, which performs a linear reciprocating movement in the lateral direction in response to the expansion and compression of the thread control cylinder 32.
The connection of the end portion 35a to the other end of the connecting rod 35 connected to the expanded part 3c connected to the hook for hanging the threads 3 is bent down to a depth corresponding to the thickness of the expanded part 3c. The contact pin 110 protrudes upward from the connecting end portion 35a of the downward-curved connecting rod 35. On the other hand, the expanded portion 3c is provided with a connecting hole 111, which is mounted on top of the contact pin 110 and extends upward over the pin 110. This eliminates the need to perform a rigid connection operation of the connecting rod 35 and the extended part 3c, for example, being released from the state of mutual engagement between two loosened set screws or the like when the left side of the base of the needle plate 11L is removed from the platform of the sewing machine B by disconnecting it from the platform of the sewing machine B.
That is, the connecting hole 111 of the expanded portion 3c can be extended upward from the pin 110, and the blocking state between the connecting rod 35 and the expanded portion 3c (of the thread hanging hook 3) can only be released by raising the base of the left side of the needle plate 11L. In addition, when installing the base of the left side of the needle plate 11L to the platform of the sewing machine, only by moving the left side of the base of the needle plate 11L upward from the platform of the sewing machine B, the connecting hole 111 is worn on the pin 110 from above, thereby allowing the connecting rod 35 and the extended part 3c (hook hanging the thread 3) return to the locked state. The connecting end portion 35a of the connecting rod 35 need not be bent downward. That is, the connecting rod 35 may well be in the form of a flat plate.
The base of the attachment of the pivoting (swinging) lever (movable base) 92, which supports the pivoting (swinging) lever 9 of the locking mechanism so that it swings around the vertical support axis 90, is attached to the base of the cylinder 11R in order to provide a lateral adjustment position with using a long hole 93, elongated laterally, using the set screw 94. Thus, even after the base of the cylinder 11R is mounted in a locked state in the platform The shape of the sewing machine B using the screw element 107, the timing of the slipping of the looper 1 from the loop of the needle thread 20a held by the hook for hanging the thread 3 can be adjusted by laterally adjusting the position of the attachment base of the pivoting arm mount 92 relative to the base of the cylinder 11 R. This provides self-locking (self-looping), which provides prevention of the opening of the seam.
In a multi-thread chain stitch sewing machine with a horizontal cylindrical platform platform and with a seam prevention device Ç having the above-described features, when a seam prevention device Ç is installed in the sewing machine platform B, the left base of the needle plate 11L and the right base of the cylinder 11R, which obtained by dividing the base of the needle plate 11 into the right and left parts, can be individually attached to the platform of the sewing machine B. Therefore, in comparison with lzovaniem one long and large needle plate in case of technical solutions described in the previously filed application for patent by the present applicant, the attach operation (setting) of the entire device prevent unraveling seam Ç with respect to the sewing machine bed B can be performed easily and with less effort.
In addition, if after installing the base of the needle plate 11 (the left part of the base of the needle plate 11L and the right base of the cylinder 11R) in the platform of the sewing machine B, it becomes necessary to adjust the stitch to perform the sewing action by correcting the position and loci of movement of the components located below the base needle plate 11 and are located inside the platform of the sewing machine B, such as looper 1, and the elements of their drives, or it becomes necessary to carry out maintenance, for example, repair t and replacement of various types of components located below the base of the needle plate 11 and inside the platform of the sewing machine B, there is no need to remove the right base of the cylinder 11R, to which the thread control cylinder 32 and stopper cylinder 43 are connected, respectively having air pipes 33 and 43 attached to them and greatly interfering with their easy installation. A sufficiently wide working space can only be achieved by unscrewing and removing the left 11L part of the base of the needle plate from the platform of the sewing machine B.
Therefore, adjustment of sewing operations and maintenance, such as repair and replacement of various types of components located inside the platform of the sewing machine B, can be performed very easily, simply and efficiently only by operating with the small and light left part of the needle base of the plate 11L to which the air supply pipes 33 and 34 do not cling. Thus, satisfactory performance of the sewing function and the function of preventing the opening of the seam can be continuously demonstrated with excellent reproducibility, thereby allowing to solve the problems that remained unresolved in the patent application filed earlier by the present applicant.
In the present embodiment, a structure is used in which the pivoting (swinging) lever 9 in the locking mechanism is pushed by the action of the spring 91 in the direction in which the thread hanging hook in the needle thread support mechanism is in the standby (ready) position.
Thus, the action of the locking element 4 in the opposite direction (the action in the direction in which the hook hanging the thread is in the ready position) is due to the action of the force of the spring 9. This allows you to use the cylinder of one type of action as the cylinder of the stopper (stopper) 42 to bring in the action of the pivot arm 9, which engages with or disengages from part of the locking element 4, thereby achieving a reduction in size and lowering the cost of the cylinder of the stopper 42.
The present embodiment also uses a structure in which the needle thread control cylinder 32 and the stopper locking cylinder 42 are rigidly fixed to the lower surface of the mounting base of the cylinder 11R in a vertical two-stage fashion. In this way, the flat space occupied by the two cylinders 32 and 42 can be reduced for compactness and placement of the seam prevention device H, thereby allowing the seam prevention device размест to fit well inside the platform of the sewing machine B, compared to the case when the two cylinders 32 and 42 are located in separate positions (side-by-side arrangement), as is the case with the technical solution described in the previously filed patent application by the present applicant.
The present embodiment further utilizes the attachment structure of the looper thread holder 6 to the hook of the suspension of the thread 3 of the thread holding mechanism. The looper thread holder 6 holds the looper thread extending from the looper 1 to the fabric in a more forward position than the lower drop position of the needle 2 by swinging with the hook the suspension of the thread 3 in a plane almost parallel to the plane of the needle plate around the vertical support axis 30 between the gripping position threads, hold position and wait position. This simple design makes it possible to reliably position the looper thread 10 together with the needle thread 20. Thus, the loop self-locking (self-looping) can be confidently performed to further ensure the effect of preventing the seam from blooming.
In particular, according to the position of the movable holder of the looper thread holder 6 with respect to the hanging hook of the thread 3, the relative position of the needle thread 20 and the looper thread 10 can be appropriately set, and self-locking (loop self-formation (self-looping)) can be reliably performed to further enhance the prevention effect dissolving the seam. [0102]
The present embodiment further utilizes a design in which the pin 110 projects upward from the connecting end portion of the connecting rod 35a of the connecting rod 35, and the connecting hole 111 is put on the pin 110 from above, thereby forming the end connecting portion (the expanded portion 3c is closer to the hook for hanging the thread 3 Therefore, when the left side of the base of the needle plate 11L is detached and pulled upward from the platform of the sewing machine B to adjust the stitch and service to be performed, for example, such as nta and replacement of various types of components located in the platform of the sewing machine B, the hook for hanging the threads 3 and the connecting rod 35 can be disconnected from each other only by lifting the left part of the base of the needle plate 11L without performing laborious operations such as loosening and removing the screw connecting the connecting rod 35 and the extended portion 3c is closer to the hook for hanging the threads 3, or by removing the connecting pin.
In addition, after adjustment and maintenance, the hanging hook of the thread 3 and the connecting rod 35 can only be returned to the set connection state by attaching the left side of the base of the needle plate 11L to the platform of the sewing machine B from above. This additionally saves setup and maintenance work.
Although an embodiment of the invention has been described using pneumatic cylinders as hook and stop actuators, electromagnetic solenoids can also be used as actuators.
Although the case described above also describes the formation of a multi-thread seam of a chain stitch with two needles 20 and 20 and one thread of a looper 10, this applies to a seam that is formed by several needles forming a seam of a double chain stitch using three or more needle threads, or one that forms a single-needle seam of a chain stitch with a single thread, or a sewing machine with a multi-thread chain stitch to sew surface seams of a chain stitch.
The above option also relates to the case of preventing the opening of the seam in which one of the loops of the needle thread formed by the two needle threads 20 and 20 is caught and held in the holding position, and in this state, a sewing action is performed to make one stitch for self-locking (self-looping) . In addition, a plurality of loops of needle threads can be caught and held in the holding position, and sewing actions in the holding state can be performed on two or more stitches without being limited to one stitch.
In the above embodiment, the invention also includes the case where the looper thread holder 6 of the suspension hook of the needle thread holding mechanism (needle thread holder mechanism) is preferably provided with a looper thread holder that holds the looper threads exiting the looper in a more forward position compared to the lower position the needles by swinging together with the hook hanging the threads around the support shaft in a plane essentially parallel to the needle plate between the position of the grip, laying down hold and waiting position. In addition, the looper holder 6 and the thread hook 3 can be individually arranged and individually controlled by dedicated drives other than the thread control cylinder 32 to operate the thread hook 3. In addition, it is not necessary to install the looper thread holder 6 .
Industrial applicability
The base of the needle plate is divided into left and right sections, which are made with the possibility of individual installation in the form of the left supporting part of the base of the needle platinum and the right base of the cylinder. Thus, the attachment (installation) of the device to prevent the opening of the seam in the platform of the sewing machine and the adjustment of the sewing actions and maintenance and repair and replacement of various types of components located inside the platform of the sewing machine can be easily carried out at lower labor costs, which allows it to be considered A convenient application to multi-thread chain stitch sewing machines.
Bibliography 1. Japanese Patent Application No. 2011-016821. 2. Japanese Patent Application No. 2011 -115174.

Images