JPH0234195A - Sewing machine with uneven material feeding preventing upper and lower feed dogs device - Google Patents

Abstract

PURPOSE:To prevent an uneven sewing even in the case of the sewn article of any raw material by separating a lower feed dog and an upper feed dog to be lifted in being turned to it mutually, thereafter, causing them to abut, engaging the sewn article between the upper and lower feed dogs and executing a feed movement. CONSTITUTION:An upper feed dog 6 to be lifted in being fit-in-inserted into a bottom surface open groove part 4 of a presser foot 2 is provided, and it is made to appear and sink from a bottom surface 3. It is faced to a lower feed dog 9 to appear and sink on a throat plate upper surface P, they are separated from each other, thereafter, they are made to abut, a sewn article B is engaged between the upper and lower feed dogs 6 and 9, they are fed and moved, a sewing needle N sews the sewn article B, simultaneously, both are separated, they are returned up to the former positions, and a cycle into the next feeding action is repeated. Consequently, since the sewn article B cannot be fed and moved in being hindered by the presser foot 2, even in the case of the raw material with a bristle wool thick fabric, the uneven sewing cannot be generated. Since the pressure of the presser foot 2 is not applied even to the sewn article B made of leather as the raw material, the sewn article B can be easily engaged with the upper and lower feed dogs 6 and 9 and moved to the feed positions.

Description

[Detailed Description of the Invention] (Field of Industrial Application) This invention eliminates the causes of wrinkles that cannot be repaired due to the stretching of the workpiece that occurs during sewing with a sewing machine, and the problems that cause sewing failures that occur because the workpiece does not slip. Prevents seams from slipping,
This invention relates to a sewing machine with an upper and lower feed dog device.

(Prior Art) Conventionally, as shown in FIG. 14, a sewing machine's workpiece feeding device presses a workpiece B, which is made by overlapping an upper material C8 and a lower material C2, from above with a presser foot. However, a saw blade-shaped feed dog R is made to appear and retract from the upper surface P of the throat plate from below, and the fabric is moved by a feeding action by an elliptical motion. In this case, the lower material C2 is directly connected to the feed dog R that is in contact with the contact surface a.
However, the upper fabric C2 receives the feeding action indirectly through the frictional resistance of the contact surface 1) between the two, while the pressure of the presser foot creates a frictional resistance on the contacting surface C that prevents the feeding action. For example, in the case of fabrics made of materials that are easily stretched, it is impossible to avoid the occurrence of wrinkles in the seams due to the occurrence of seams that cannot be repaired. Further, in the case of an object to be sewn made of a non-slip material such as leather or vinyl, the pressure of the presser foot I5 impedes the feeding action of the upper fabric C1, resulting in a problem in that sewing cannot be fed.

Various measures have been taken to prevent sewing errors in the workpiece B of these sewing machines, such as the sewing error prevention axotiment proposed in Japanese Utility Model Publication No. 5,633,496 and Japanese Patent Application No. 62-219891, and fabrics using a throat plate and feed dog. There is a sewing sagging prevention device that has a feed-stopping mechanism.

(Problems to be Solved by the Invention) This invention solves the problem of thick and stretched workpieces (problems to be solved by the invention), which could not be solved even with the conventional anti-slip device described in the prior art.
This solves problems when sewing objects that cannot be sewn using regular sewing machines because they are made of non-slip materials such as leather, vinyl, etc. (for example, trousers with hair legs, etc.), and can be used to sew objects made of any material. An object of the present invention is to provide a sewing machine that can easily sew while preventing the above problems.

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention adjusts the lowering position of the lifting guide so that there is no pressure from the presser foot pressing the workpiece on the throat plate of the sewing machine. , an elevating mechanism formed in such a way that the upper feed dog, which moves up and down in an elliptical manner in the vertical direction while facing the lower feed dog that appears and retracts from the upper surface of the needle plate of the sewing machine, moves up and down in synchrony with the former, so that the upper feed dog appears and retracts from the groove in the bottom of the presser foot. This invention relates to a sewing machine with an upper and lower feed dog device for preventing slippage in sewing, which is provided with a mechanism, and feeds and feeds a workpiece by biting the workpiece between upper and lower feed teeth that are spaced apart from each other and then abut against each other.

In order to synchronize and interlock the lower feed dog of L, the elevating mechanisms of both are directly connected and driven on the same axis of a common drive mechanism.F, which moves up and down in an elliptical direction in the opposite direction to the lower feed dog. A support leg is provided on the support piece that protrudes through the tips of the upper and lower pots, and a guide arm in the shape of a 17 is installed on the cantilever-shaped sliding table, and the upper feed dog is protruded from the other side end. 2 to form an elevating mechanism for the upper feed dog.

The guide arm is formed so that it can be lifted up and down by the lift guide of the presser foot and can be moved up and down along with the presser foot, and is also connected to the lift guide of the presser foot to prevent the other end of the guide arm from steadying. It is loaded with springs and can be raised and lowered.

(for Kusaku) The operation of this invention will be explained with reference to the drawings of the embodiments.

In the conventional technique, the causes of seaming deviation are the pressure of the presser foot 2 that presses the workpiece B on the throat plate P and the feeding action of the lower feed dog 9 that retracts from the throat plate P'2 from below. In view of the above, the technical means of the present invention is to first lower the presser foot 2 to a position where it contacts the upper surface of the workpiece B so that no pressing force is applied to the sewing machine shown in FIG. The lifting stroke of the lifting guide G is adjusted by the holding cylinder screw S. An upper feed dog 6 is provided which is fitted into the bottom opening groove 4 of the presser foot 2 and moves up and down in an elliptical motion in the vertical direction. After facing and separating from each other, they are brought into contact with each other, and the workpiece B is bitten between the two lower feed teeth 6°9, and then the workpiece B is fed and moved, and the sewing needle N stitches the workpiece B. , the two are separated, and the two are returned to their original positions.''The second and next feeding operation begins, and the cycle is repeated.

Therefore, the material to be sewn B is not fed and moved while being obstructed by the presser foot 2, so that even thick material with hair can be sewn completely without any misalignment. In addition, since no pressure is applied to the sewing material B made of leather or vinyl, it can be easily bitten by the upper and lower feed dogs 6 and 9 and moved to the feed position.

Therefore, the effect of being able to sew any material while preventing any misalignment is extremely large.

Next, the elevating mechanism of the lower feed@9 shown in FIG. As the feed base E moves in an elliptical downward direction through the cooperative action of the vertically moving vertical pot 39, the lower feed @9, which is screwed in a cantilevered manner on top of the base E, appears and retracts from the upper surface P of the throat plate. is configured to do so.

As shown in FIG. 11, the upper feed @ 6 lifting mechanism 5, which is driven in synchronization with this, is directly connected to the same axis of the common drive mechanism 29, and moves up and down in the opposite direction to the lower feed dog 9. The shaft end 2 of the drive shaft 2 on the upper and lower pots 39a side moves in an elliptical manner while
As shown in Fig. 4 and 12, a guide arm 13 with a support leg 26 suspended in a cantilevered manner is installed on a fixed support piece 25, and the guide arm 13 is inserted into the bottom opening groove 4 of the presser foot 2. It causes the teeth 6 to appear and disappear, and as shown in Figures 1 and 2),
The presser foot 2 is formed to be able to rise and fall freely together with the guide arm 13 via a locking member 16 provided on the lifting guide G, and a spring 20 is elastically loaded between the two to provide a steady rest. The synchronized feeding action of feed @6 and 9 can be effectively performed.

(Example) Embodiments of this invention will be described below based on the drawings.

FIGS. 1 to 3 show the main parts of a sewing machine 1 with a vertical feed dog device for preventing misalignment according to the present invention.

The lifting guide G, which is vertically installed on the head H of the sewing machine main body M and can be raised and lowered via a lever V, is moved up and down by adjusting the holding cylinder screw S so that its lowering position hits the upper surface of the workpiece B. The workpiece B is sandwiched between the bottom surface 3 of the presser foot 2 screwed onto the lower end of the guide G and the upper surface P of the throat plate so as to be in contact with each other.
Make sure that no pressing force is applied to the

Therefore, the presser foot 2 is fitted into the bottom opening groove 4,
The guide means for the upper feed dog 6 that protrudes and retracts from the bottom surface 3 via the lifting mechanism 5 acts as a ruler in the stitching direction of the workpiece B, and is normally formed on the presser foot 2 before and after the feed direction. In order to guide the presser foot 2, a presser foot 2 is formed with the rear side of the tip portion 7 bent upwards missing, and the presser foot 2 is inserted into the bottom opening groove 4 from the rear in the suture feeding direction, and moves in an elliptical direction in the vertical direction. To prevent the feed dog 6 from interfering with the presser foot 2. The upper feed dog 6 formed in a stepped L-shape has a rack 8 like a saw blade on the lower surface of the tip, and a lower feed dog 9 has three rows of racks 10, 11 and 12 that appear and retract on the upper surface P of the throat plate. The guide arm 13 is attached to a vertical end 15 formed by bending the other end 14 of the guide arm 13 which faces the guide arm 13 and which raises and lowers the guide arm 13 . The other end 14 of the guide arm 13 is connected to a horizontal locking pin 18 that projects from a hook-shaped locking piece 17 that projects through a locking member 16 provided on the lifting guide G to which the presser foot 2 is attached. can be lifted up and down together with the presser foot 2 by locking it. Further, a spring 20 is elastically loaded to connect the attachment part 9 of the upper feed dog 6 provided on the other end 14 of the guide arm 13 and the locking member 16 provided on the lifting guide G of the presser foot 2. A steady rest for the other end 14 of the arm 13 is formed. The shaft end 24 of the drive shaft 2 is supported by projecting the head 23 of the upper and lower rods 22 onto which the drive shaft 21, which is located close to the base of the sewing machine body M and straddles the table T, is inserted. A support piece 25 is fixedly attached to the support piece 25, and the support leg 26, which is vertically attached to the support piece 25 which is driven to swing up and down, is bent in a cantilever shape as one end, and is formed into an L-shape parallel to the plane of the table T. A guide arm 13 is constructed, and an upper feed dog 6 is attached to the other end 14. A triangular reinforcing plate 28 is attached to the L-shaped framework of the guide arm 13.

Next, a mechanism for raising and lowering the upper and lower feed dogs 6 and 9 will be explained.

As shown in FIG. 4, the feed shaft 30 and the vertical shaft 3 of the drive mechanism
One side end 38 of a support arm 37 perpendicular to the top 36 of a support piece 350 pivoted via a horizontal shaft 34 pivoted to the tip 33 of a feed rod 32a pivoted to the top 36 of the feed rod 32a.
The lower feed dog 9 is connected via a drive shaft 21 rotatably screwed to the
While transmitting the horizontal rotation of the feed rod 32a of the upper feed dog 6 which is pivoted in the same direction as the feed rod 32 of The tip shaft of the drive shaft 21 is attached to the free bearing 42 of the vertical rod 22 which is vertically installed via the horizontal shaft 41 (7). 43 is inserted and supported, and when the vertical shaft 31 rotates left and right, the top end 40 of the top and bottom bell 39 of the lower feed dog 9 moves up and down, and the top end of the top and bottom bell 39a of the top feed dog 6 moves vertically. As shown in FIG. 12, the support piece 25 is moved in an elliptical direction in the vertical direction of the shaft end 24 of the drive shaft 21 supported by the vertical rod 22, which is interlocked with the vertical movement of the 4Oa in the vertical direction. The support piece 25 is fixed to the drive shaft 21 by screwing set screws 44 from the top and side surfaces so that the top surface 45 is parallel to the top surface of the table.The top surface 45 of the support piece 25 The support leg 26 is inserted into the mounting hole 46 of the support leg 26 of the guide arm 13, which is bored perpendicular to the drive shaft 21.
is fixed by screwing a set screw 44 from two orthogonal sides thereof, and the vertical elliptical movement of the support piece 25 is controlled via the support leg 26 on the other end 14 of the guide arm 13. It is formed to transmit up to tooth 6. Figure 13 shows drive shaft 2I
The vertical shaft 31 of the drive mechanism 29 connects the upper and lower bellows 39a of the upper feed dog 6, which has a distal end 40a to which the horizontal shaft 41, which supports the distal end shaft 43 of the upper feed dog 6, is pivoted.
This figure shows an exploded view of the assembly.

Next, the feeding action of the workpiece by raising and lowering the upper and lower feed dogs will be explained with reference to FIGS. 5 to 8.

In operation stage 1 in FIG. 5, the sewing needle N has risen to the highest point and is at the position where it is about to start descending, and the lower feed dog 9 has reached the highest point, which is 2 millimeters higher than the upper surface P of the throat plate, and is at the highest point. The opposing upper feed dog 6 also reaches its lowest point, which is 2 millimeters higher than the bottom opening groove 4 of the presser foot 2, and the tops of the saw blades of the upper and lower feed dogs 6.9 just come into contact, and the gap becomes O. .

Therefore, when the workpiece B is sandwiched between the two, and the feed dog is positioned closest to the center line XX of the sewing needle N, with the tip 47 of the upper feed dog 6 protruding,
Three parallel ranks 10 of the lower feed dog 9 shown in FIG.
, 11.12, the relative positions in the feeding direction are formed so that they come into contact with each other, leaving a saw blade at the tip of the short rack 11 at the center.

Therefore, the other two racks 10 and 12 of the lower feed dog 9 rose to the upper surface P of the throat plate and pushed up the workpiece ′B that was in contact with the bottom surface 3 of the tip 7 of the presser foot 2 from below. It is in a state.

Therefore, it is natural that the workpiece B shown in the imaginary line is caught between the upper and lower feed teeth 6.9 by the thickness of the materials above and below it.

Next, in action stage H in FIG. 6, while the sewing needle N is descending, the lower feed dog 9 moves 6 mm in the feed direction while reaching the highest point, while the upper feed dog 9 reaches the lowest point. The feed dog 6 also moves 6 mm in the feed direction.

Therefore, the workpiece B sandwiched between the two moves to the 6-thread feed position, and the sewing needle N descends to the next stitching point with the sewing needle N, and pierces the fabric.

Next, in action stage (3) in FIG. 7, when the sewing needle N reaches the lowest point and is about to start rising, the lower feed dog 9 also moves 2 mm from the top surface P of the throat plate, which has descended 4 mm to the lowest point. It is in a state of being submerged downward.

On the - side, the upper feed dog 6 rises 4 mm to the maximum point, and is recessed 2 mm above the bottom opening groove 4 of the presser foot 2.

Therefore, the workpiece B is released from being bitten by the two, the gap between the two saw blades becomes 4 mm, and the workpiece B comes into contact with the presser foot 2 at the upper surface P of the throat plate.

Next, when the sewing needle N starts to rise in operation stage (3) in FIG. The feed dog 6 of the sumo wrestler moves while being recessed below P, and the feed dog 6 of the sumo wrestler similarly moves to the front position 6 mm to the right while recessed into the bottom opening part 4 of the presser foot 2, and the sewing material is sewn. Object B is not sandwiched by the 4 mm gap between the two.

Next, when the sewing needle N further rises, the lower feed dog 9
The tips of the saw blades are exposed to the upper surface P of the throat plate and the tips of the saw blades are exposed to the upper surface P of the needle plate. The suturing action is performed by a cycle of coming out to the front position and repeating the action of action stage (3).

As shown in FIGS. 9 and 10, the rack 8 of the upper feed dog 6 is located between the two outer racks 10 and 12 in the suture feed direction with respect to the lower feed dog 9. - It has a cup width and is formed to face the narrow central rack 11, and the biting width of the workpiece B does not exceed the tooth width of the lower feed dog.

(Effects of the Invention) Since the present invention has the above-described configuration, it has the following advantages.

(1) The upper and lower feed dog device for preventing sewing misalignment of the present invention according to claim (1) eliminates the pressure on the workpiece by the pressure of the presser foot, which is a cause of occurrence of sewing misalignment in the conventional technology, The presser foot is brought into contact with the workpiece, and elliptical movements facing each other in the vertical direction are performed in synchronization, and upper and lower feed dogs are provided that come into contact after being separated from each other, and the workpiece is fed and moved by being sandwiched between them. This allows you to prevent misaligned stitches, and since the presser foot does not slip due to the pressure of the presser foot, it is now possible to easily feed and move leather and vinyl materials, which were previously impossible to feed. To be able to sew any material without causing wrinkles that cannot be repaired by preventing sewage on any material that can be easily sewn even though conventionally there was no means for preventing sewage sagging.

(2) The elevating mechanism for the upper and lower feed dogs according to claim (2) has a simple structure in which the elevating and lowering functions are synchronized by being driven from the same axis of the drive mechanism.

(3) Since the guide arm of the upper feed dog as claimed in claim (3) is installed and has a reasonable structure that transmits the raising and lowering function of the upper feed dog, the feeding action is performed reliably and the operation is easy. To be.

(4) It? (Since the guide arm of the 4th section is provided with a swing stop means, the operation of the upper and lower feed dogs must be reliable.

[Brief explanation of the drawing]

Figure 1 is a rear perspective view of the main body of a sewing machine with an upper and lower feed dog device that prevents sewing errors according to the present invention, Figure 2 is a left side perspective view, Figure 3 is a front perspective view, and Figure 4 is an upper and lower side perspective view. A partial assembly explanatory diagram (front view) of the feed dog and its elevating mechanism, FIG. 5 is a front view explaining the operation of the upper and lower feed dogs in operation stage I, FIG. 6 is a front view explaining the operation in operation stage H, and FIG. FIG. 8 is a front view explaining the action of action stage (■), FIG. 9 is a partial cross-sectional view of FIG.
11 is a perspective view illustrating the assembly of the drive mechanism directly connected to the upper feed dog elevating mechanism; FIG. 12 is a perspective view illustrating the assembly of the upper feed dog elevating mechanism and guide arm; FIG. 13 Fig. 14 is an explanatory diagram (front view) of the partially extended assembly of the vertical pot side lifting mechanism, and Fig. 14 is an explanatory diagram of the feed operation of the workpiece in the conventional technology. Sewing machine with upper and lower feed dog device 2... Presser foot 4... Bottom opening section 5... Lifting mechanism
6... Upper feed dog 9... Lower feed dog 13...
Guide arm 14...other end 16...locking member 18...locking pin 19...attachment part 20...
・Spring 21...Drive shaft 22...Upper and lower rod 24...Shaft end 25...
- Support piece 26...Support leg 27...-side end portion 29...Drive mechanism 30...
Feed shaft 31...-F lower shaft 32a...Feed rod 39a...Upper and lower dowels 40a...Tip (upper and lower dowels) T...Table P...Throat plate'' - side Figure 13 Figure Figure ■ Figure 10

Claims (4)

[Claims] (1) A lifting mechanism is provided, which is directly connected on the same axis to the drive mechanism that drives the lifting mechanism of the lower feed dog that appears on the upper surface of the sewing machine's throat plate, and which makes an elliptical movement in the vertical direction in synchronization with and opposite to the lower feed dog. , the upper feed dog is moved in and out of the groove on the bottom of the presser foot which is set at a position where it contacts the workpiece through the guide arm, and the workpiece is moved between the upper and lower feed dogs that come into contact after being separated from each other. A sewing machine with an upper and lower feed dog device that prevents stitches from slipping and is characterized by biting and moving the feed. (2) On the same axis of the drive mechanism consisting of a feed shaft and a vertical shaft, there is a feed rod that rotates in the left and right direction in the same way as the feed rod of the lower feed dog, and an upper and lower barrel that moves up and down in the opposite direction. A drive shaft is formed so as to straddle the table, and the ends of the drive shafts are arranged so as to straddle the table. 2. The upper feed dog elevating mechanism according to claim 1, further comprising a protruding support piece. (3) At one end of the support leg, the support leg is attached to the tip of the upper and lower bells of the upper feed dog and is suspended from the support piece that protrudes from the shaft end of the drive shaft, which is raised and lowered via the vertical rod that moves up and down. An L-shaped arm is formed on a plane parallel to the folding table in a cantilevered manner as a part, and a guide arm is formed such that an upper feed dog vertically provided on the other side end retracts from the groove in the bottom of the presser foot. Claim (2) characterized in that, in addition to the construction, a locking pin for lifting the other end of the guide arm is provided on a locking member provided on a guide for lifting and lowering the presser foot, so that the guide arm can be freely raised and lowered together with the presser foot. Lifting mechanism of the feed dog above. (4) A spring connecting the attachment part of the upper feed dog provided on the other end of the guide arm and the locking member provided on the lifting guide of the presser foot is elastically loaded, so that the other end of the guide arm swings. The guide arm according to claim 3, further comprising a stop.