JP2005000416A - Looper thread take-up supporting device of sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent leakage of lubrication oil when a thread is cut. <P>SOLUTION: The looper thread take-up supporting device 20 is mounted between a thread source and a sewing position. The looper thread take-up supporting device 20 comprises a rotary sleeve body 21 fixed to a rotation shaft 66 supporting a looper thread take-up plate 61, slide-contacting/rotating at the outer peripheral edge of a looper thread L fed to the sewing position, to the looper thread L and rotating as interlocking with a motor of the sewing machine, a bearing body 22 of the rotation shaft 66 adjacent to the looper thread take-up plate 61, and an oil seal 23 disposed in an opening 22a formed around the rotation shaft 66 from the end surface on the looper thread take-up plate side of the bearing body 22. The looper thread take-up supporting device 20 also has a lid body 24 with a center hole 24d for inserting the rotation shaft 66 for closing the opening 22a. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lower thread cam support device for a sewing machine that uses a lower thread.
[0002]
[Prior art]
The lower thread (looper thread) is led from the lower thread supply part to the looper in the bed part of the double chain stitch sewing machine, and the rotary lower thread for feeding the thread from the lower thread supply part in the path A cam plate and its supporting device are provided.
Such a lower thread cam plate support device supports a lower thread cam plate that is slidably rotated at an outer edge portion of a lower thread supplied to a sewing position, and a lower shaft (rotating shaft) that rotates in conjunction with a sewing machine motor. A rotating sleeve body that is fixed, a bearing body of a lower shaft adjacent to the lower thread cam plate, and an oil seal disposed in an opening formed around the lower shaft from the lower thread cam plate side end surface of the bearing body; (See Patent Document 1).
[0003]
The lower thread cam plate is supported by a rotating sleeve body, and these rotate together with the lower shaft. At this time, the bearing body rotatably supports the lower shaft and the lubricating oil is supplied to the gap with the lower shaft. This lubricating oil is sealed so as not to leak to the lower thread cam plate side by an oil seal provided at the opening.
The outer periphery of the lower thread cam plate is provided with a region having a short distance from the rotation center and a long region, and the lower thread is stretched so as to always contact the outer periphery of the lower thread cam plate. Therefore, a small amount of slack is secured while the lower thread is in sliding contact with the lower thread cam plate in a region where the distance from the rotation center is short, and when the lower thread is slid in contact with a region where the distance from the rotation center is long, the slack The amount is increased, and tension is applied to the lower thread, and the loop formed on the looper side is tightened. When the lower thread again comes into sliding contact with a region where the distance from the rotation center of the lower thread cam plate is short, the tension application state of the lower thread is canceled. At the time of sewing, each lower thread cam plate is rotated in synchronism with the operation of the looper, and the above operation is repeated at a constant cycle.
[0004]
[Patent Document 1]
Japanese Utility Model Publication No. 6-16616 (FIG. 2)
[0005]
[Problems to be solved by the invention]
By the way, when an accident occurs in which the lower thread is cut on the looper side during sewing, the lower thread becomes free on the looper side, and is released while being captured by each lower thread cam plate. Without rotating the lower thread cam plate. In such a state, when entering between the rotating sleeve body and the bearing body, the lower thread fed from the thread supply source may get entangled with the lower shaft.
When the amount of entanglement increases, the lower thread becomes a bundle and gradually spreads along the lower shaft, and the lower thread bundled may enter the opening of the bearing body. The oil seal provided inside the opening has a structure that prevents the internal valve from opening in the direction that does not allow the lubricating oil to leak. The valve is opened by the thread, and the lubricating oil leaks from the oil seal.
Moreover, when the lubricating oil leaks from the oil seal and reaches the rotating sleeve body and the lower thread cam plate, it is scattered by the centrifugal force of the lower thread cam plate, or the lower thread and the passage area thereof are contaminated with oil. As a result, there was a case where even the sewn product was stained with oil.
[0006]
An object of the present invention is to eliminate lubricating oil leakage when a thread is cut.
[0007]
[Means for Solving the Problems]
The invention according to claim 1 is a lower thread cam support device (20) provided between a thread supply source and a sewing position, for example, as shown in FIG. 6, wherein the lower thread (L) is supplied to the sewing position. A rotating sleeve body (21) fixed to a rotating shaft (66) rotating in conjunction with a sewing machine motor and supporting a lower thread cam plate (61) slidingly rotating at an outer edge thereof, and a lower thread cam plate A bearing body (22) of an adjacent rotating shaft, and an oil seal (23) disposed inside an opening (22a) formed around the rotating shaft from the lower thread cam plate side end surface of the bearing body. Further, a configuration is adopted in which a lid (24) is provided which has a central hole (24d) through which the rotating shaft is inserted and which closes the opening of the bearing body.
The “sewing position” refers to a place where a sewing operation is performed with a thread on a sewing object on the sewing machine.
[0008]
In the above configuration, even if the lower thread that is in sliding contact with the lower thread cam plate is cut, enters between the rotating sleeve body and the bearing body, is wound around the rotating shaft, and becomes a bundle, the lower thread The lump is blocked by the lid and cannot enter the opening of the bearing body. Therefore, the oil seal is maintained in a normal state, and lubricating oil leakage is avoided.
[0009]
The invention according to claim 2 is a lower thread cam support device (20) provided between the thread supply source and the sewing position, and is slidably rotated at the outer edge portion of the lower thread (L) supplied to the sewing position. The rotary sleeve body (21) that supports the lower thread cam plate (61) that is fixed to the rotating shaft (66) that rotates in conjunction with the sewing machine motor, and the frame (106) adjacent to the lower thread cam plate. A rotary shaft bearing body (22) provided in the joint hole (106a) and an oil seal (23) disposed inside the engagement hole have a central hole (24d) through which the rotary shaft is inserted. In addition, a lid (24) for closing the engagement hole is provided.
The “sewing position” is the same as that of the first aspect of the invention.
[0010]
In the above configuration, even when the lower thread slidingly contacting the lower thread cam plate is cut, enters between the rotating sleeve body and the frame, is wound around the rotating shaft, and is bundled, The bundle is blocked by the lid and cannot enter the engagement hole. Therefore, the oil seal is maintained in a normal state, and lubricating oil leakage is avoided.
[0011]
The invention according to claim 3 has the same configuration as the invention according to claim 1 or 2, and the bearing body (22) is fixedly supported on the frame (106) in a state in which the rotation of the rotating shaft (66) is allowed. It has been configured to be.
With the above configuration, the lid does not rotate because it is supported by a bearing body or a frame that does not rotate. Therefore, even if the cut lower thread comes into contact with the lid, it is not caught.
[0012]
The invention described in claim 4 has the same configuration as that of the invention described in claim 1, 2, or 3, and, for example, as shown in FIG. 6, the lid (24) is at least from the bearing body (22) to the rotating sleeve. The structure of having a cylindrical part (24b) covering the peripheral surface of the rotating shaft (66) up to the body (21) is adopted.
With this configuration, even when the cut lower thread enters between the rotating sleeve body and the bearing body, the contact with the rotating shaft that causes the winding is suppressed. For this reason, the bobbin thread itself is effectively suppressed.
[0013]
The invention described in claim 5 has the same configuration as that of the invention described in claim 4, and, as shown in FIG. 6, for example, an opening formed around the rotating shaft from the bearing body side end surface of the rotating sleeve body (21). A portion (21a) is provided, and the cylindrical portion (24b) of the lid (24) is set to have a length that penetrates into the opening of the rotating sleeve body.
In the above configuration, the same effect as that of the invention described in claim 2 is obtained, and the cylindrical portion of the lid body is disposed so as to enter the opening portion of the rotating sleeve body, so between the bearing body and the rotating sleeve body, The region where the peripheral surface of the rotating shaft is exposed is almost eliminated, and the lower thread winding itself is more effectively suppressed.
[0014]
The invention described in claim 6 has the same configuration as that of the invention described in claim 1, 2, 3, 4 or 5, and for example, as shown in FIG. 6, the lid (24) is a bearing body (22). The boss | hub part (24a) fitted to this opening part (22a) is provided.
In the above configuration, the same effect as the invention described in each of the above claims is achieved, and the boss portion provided on the lid body is fitted into the opening of the bearing body, so the bobbin thread between the lid body and the bearing body Effectively reduces the intrusion of the lower thread, and more effectively suppresses the bobbin thread itself.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
(Overall configuration of the embodiment)
A lower thread cam support device 20 of a double chain stitch sewing machine 100 according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a perspective view showing a state in which the lower thread cam support device 20 is incorporated in the sewing machine 100.
[0016]
As shown in FIG. 1, the double chain stitch sewing machine 100 includes a bed portion 101 having a box shape, and a vertical body portion (not shown) is erected from the right end portion of the bed portion 101. An arm part (not shown) extends from the upper part of the trunk part substantially parallel to the bed part. Moreover, the Y-axis direction one end part which the bed part 101 mentions later is formed in the shape which protruded with the narrow width compared with the other site | part, and is exhibiting what is called a cylinder bed shape.
A needle plate 102 is provided on the upper surface of the bed portion 101 at a position below a sewing needle (not shown) supported at the tip of the arm portion, and the needle plate 102 has a tip portion of the feed dog 103. Is provided so that it can be withdrawn from the upper surface of the needle plate 102. The feed dog 103 feeds the cloth placed on the bed portion 101 by making an elliptical movement. A looper 104 is provided in the bed portion 101 and near the lower portion of the needle plate 102. The looper 104 is set with a lower thread (looper thread) L fed from a lower thread supply source (not shown). Has been. In addition, a lower shaft 66 as a rotation shaft is disposed in the bed portion 101 along the longitudinal direction of the bed portion 101, and an output of a sewing machine motor (not shown) is driven to rotate through a transmission mechanism, so that a looper is provided. 104 and the feed dog 103 are driven. The lower shaft 66 is rotationally driven at the same cycle in synchronization with an upper shaft (not shown) that applies a vertical driving force for the sewing needle.
On the other hand, an upper thread is set on the above-described sewing needle, and this double chain stitch sewing machine 100 performs double chain stitch sewing or flat stitch sewing on the cloth in cooperation with the sewing needle and the looper 104. is there.
In the following description, the sewing needle moves up and down in the vertical direction, the vertical movement direction is the Z-axis direction, the longitudinal direction of the bed portion 101 is the Y-axis direction, and the cloth feed direction is the X-axis direction. The three directions are orthogonal to each other.
[0017]
(Configuration around the cylinder shape of the double chain stitch machine)
Further, the configuration provided inside the cylinder portion around the bed portion 101 will be described in detail. FIG. 2 is a perspective view of the configuration around the cylinder-shaped portion, and FIG. 3 is a perspective view seen from a different direction from FIG.
The double chain stitch sewing machine 100 includes a pair of lower thread cam plates 61 and 61 that rotate in sliding contact with the lower thread L supplied to the sewing position at the outer edge thereof, and a lower thread provided between the thread supply source and the sewing position. A cam support device 20 and a lower thread holding device 10 that holds the lower thread L in a state of being engaged with the lower thread cam plates 61 and 61 are provided.
[0018]
(Lower thread cam plate)
The lower thread cam plates 61 and 61 are plate cams having the same shape, and are supported by the lower shaft 66 via the lower thread cam support device 20 so that their flat plate surfaces are close to each other and parallel to each other. ing. The lower thread cam plates 61 and 61 have a deformed disk shape and rotate by receiving the rotational driving force of the lower shaft 66. Each of the lower thread cam plates 61 and 61 has a shape in which a part of a circular outer periphery is notched flat. These lower thread cam plates 61, 61 are supported so that their shapes just overlap and rotate with the lower shaft 66.
Then, the lower thread L held by the lower thread holding device 10 is pressed and brought into contact with the outer periphery of each lower thread cam plate 61, 61 to apply tension according to the outer peripheral shape of each lower thread cam plate 61, 61. That is, since each lower thread cam plate 61, 61 has a shape including a region (part cut flat) and a region (arc-shaped part) far from the lower shaft 66 on the outer periphery thereof, the lower thread holding device When the lower thread L is held so that the lower thread L passes through the vicinity of the lower shaft 66, a small tension is applied while the lower thread L is in sliding contact with a region near the lower shaft 66 of the lower thread cam plate 61, A large tension is applied while the lower thread L is in sliding contact with a far region.
The lower thread cam plates 61 and 61 are not limited to the above-described shapes, and may be any shape that provides tension suitable for sewing.
[0019]
(Lower thread holding device)
The lower thread holding device 10 includes an arm portion 11 that is supported by the machine frame 105 of the sewing machine 100 so as to be rotatable about the Y-axis direction, and extends from the rotating end portion of the arm portion 11 toward the lower shaft 66 side. A U-plate 12 installed and supported, and a guide frame 13 extended and supported by the arm portion 11 in the same direction as the U-shaped plate 12 between the extending portions 12a and 12b which are bifurcated of the U-shaped plate 12. It has.
[0020]
The arm portion 11 is in a state in which the U-shaped plate 12 and the distal end portion of the guide frame 13 are brought close to the vicinity of the lower shaft 66 and enter the rotation region of the lower thread cam plate 61 by the swinging of the arm portion 11. The guide frame 13 can be switched to a state in which it is retracted from the rotation region of the lower thread cam plate 61.
In a state where the leading end portions of the U-shaped plate 12 and the guide frame 13 are intruded into the rotation region of the lower thread cam plate 61, one of the U-shaped plate 12 and the guide frame 13 is interposed between the extended portion 12a and the guide frame 13. The lower thread cam plate 61 enters, and the other lower thread cam plate 61 enters between the other extended portion 12 b of the U-shaped plate 12 and the guide frame 13. The lower thread L is put in tension by the lower thread cam plates 61 and 61 rotating in this state.
Further, when the U-shaped plate 12 and the guide frame 13 are retracted from the rotation region of the lower thread cam plate 61, the engaged state between the lower thread L and the lower thread cam plates 61 and 61 is released. The In this state, the threading operation of the lower thread L before the start of sewing, the maintenance work, or the repair work when trouble occurs.
[0021]
The arm portion 11 is always urged by a torsion coil spring at the proximal end thereof in a direction in which the U-shaped plate 12 and the guide frame 13 are retracted from the rotation region of the lower thread cam plate 61. . Therefore, in order to engage the lower thread L with the lower thread cam plates 61, 61, it is necessary to rotate the arm portion 11 to the lower shaft side against the elastic force of the torsion coil spring. The arm portion 11 is provided with a lock mechanism (not shown) that restricts the return when the arm portion 11 is rotated to the lower shaft 66 side to some extent. It is possible to maintain the state intruded into. This locking mechanism can release the return restriction state of the arm portion 11 by pressing the release button 14 provided on the shape portion of the machine casing 105.
[0022]
The U-shaped plate 12 is supported by the arm portion 11 with the extending portions 12a and 12b which are bifurcated facing the lower shaft 66 side, and in the vicinity of the distal ends of the extending portions 12a and 12b, respectively, in the Y-axis direction. Lower thread holding holes 12c and 12d penetrating therethrough are provided.
Further, the guide frame 13 is formed with a long hole 13 a extending along the flat plate surface of the U-shaped plate 12. The lower thread L is inserted from the thread supply source toward the looper 104 (to the left in FIG. 3) in the order of the lower thread holding hole 12d, the long hole 13a, and the lower thread holding hole 12c. Therefore, when the lower thread cam plates 61 and 61 rotate in a state where the U-shaped plate 12 and the guide frame 13 have entered the rotation area of the lower thread cam plate 61, the outer shape of the lower thread cam plates 61 and 61 becomes the outer shape. Accordingly, the lower thread L is stretched so as to bend along the elongated hole 13a, and tension is applied to the upstream side and the downstream side of the lower thread L by this projecting.
[0023]
(Lower thread cam support device)
4 is an exploded perspective view of the lower thread cam support device 20, FIG. 5 is an exploded perspective view of the lower thread cam support device 20 as seen from different directions, and FIG. 6 is a lower thread cam support device along the lower shaft 66. FIG.
3 to 6, the lower thread cam support device 20 supports a pair of lower thread cam plates 61 and 61 and is fixed to the lower shaft 66, and is adjacent to the rotary sleeve body 21. The lower shaft 66 is inserted through the bearing body 22 of the lower shaft 66, the oil seal 23 disposed inside the opening 22 a formed around the lower shaft 66 from the end surface of the bearing body 22 on the rotating sleeve body 21 side, and the lower shaft 66. And a lid 24 that closes the opening 22 a of the bearing body 22.
[0024]
The rotating sleeve body 21 is formed in a substantially cylindrical shape as a whole, and holds the lower thread cam plates 61 and 61 at predetermined intervals via the spacer 25. The rotating sleeve body 21 is fixed to the lower shaft 66 by the fixing screw 26 so as not to rotate, and the lower thread cam plates 61, 61 are press-fitted or caulked so that the rotating sleeve body 21 does not rotate. To fix and support. Accordingly, the lower thread cam plates 61 and 61 rotate together with the lower shaft 66.
Further, the end surface of the rotating sleeve body 21 on the bearing body 22 side is provided with an opening 21 a formed with its inner diameter set larger than the outer diameter of the lower shaft 66.
[0025]
The bearing body 22 is generally formed in a substantially cylindrical shape, and is fixedly supported on the machine frame 106 of the sewing machine 100 by the outer peripheral surface thereof. The lower shaft 66 is inserted into the central through hole and supports the lower shaft 66 in a rotatable state. As shown in FIG. 6, the bearing body 22 has a lubricating oil supply hole 22b penetrating from the outer peripheral surface to the inner peripheral surface, whereby the lower shaft 66 slides smoothly with respect to the inner peripheral surface. It is possible to rotate.
[0026]
Further, an opening 22 a formed to be larger than the outer diameter of the lower shaft 66 is provided on the end surface of the bearing body 22 on the rotating sleeve body 21 side. An oil seal 23 is disposed inside the opening 22a. The oil seal 23 is formed of a ring-shaped elastic material, and a bar-shaped valve body 23a for elastically closing a gap from the inner peripheral surface of the opening 22a to the outer peripheral surface of the lower shaft 66 goes around the inside. Is formed.
Accordingly, the inner region of the opening 22 a of the bearing body 22 forms a space sealed by the oil seal 23. The bearing body 22 is formed with an oil drain hole 22c penetrating from the inner space of the opening 22a to the end surface (the right end surface in FIG. 6) opposite to the rotary sleeve body 21. Thus, even when the lubricating oil supplied from the lubricating oil supply hole 22b passes through the gap between the lower shaft 66 and the bearing body 22 and accumulates in the inner space of the opening 22a, the oil is discharged from the oil draining hole 22c. It is possible.
[0027]
A lid 24 is attached to the opening 22a of the bearing body 22 and is closed. The lid body 24 is a substantially cylindrical member having a central hole 24d through which the lower shaft 66 is inserted and made of metal or resin such as iron or plastic. One end portion of the lid body 24 is provided with an insertion cylindrical portion 24a as a boss portion to be inserted into the opening portion 22a of the bearing body 22, and the other end portion can enter the opening portion 21a of the rotating sleeve body 21. A covering cylindrical portion 24b extending to the length is provided, and a flange-like portion 24c that contacts the end surface of the bearing body 22 on the rotating sleeve body 21 side is provided at the boundary between the cylindrical portions 24a and 24b.
[0028]
The lid 24 has a uniform inner diameter and is set slightly larger than the outer diameter of the lower shaft 66 (about 0.2 to 0.4 [mm] in radius). That is, the inner peripheral surface of the lid body 24 maintains a non-contact state with respect to the rotating lower shaft 66, and the lid body 24 itself maintains a non-rotating state together with the bearing body 22.
Further, the insertion cylindrical portion 24a of the lid body 24 has an outer diameter that is substantially equal to the inner diameter of the opening 22a of the bearing body 22 and is capable of maintaining the insertion state of the lid body 24 in the inserted state. Is set to the size of
Further, the outer diameter of the covered cylindrical portion 24 b of the lid body 24 is set to be sufficiently small so as to generate a gap with the inner peripheral surface of the opening portion 21 a of the rotating sleeve body 21. The covered cylindrical portion 24 b is set to have a length that penetrates to the opening 21 a of the rotating sleeve body 21, and thus covers the outer periphery of the lower shaft 66 between the bearing body 22 and the rotating sleeve body 21. be able to.
[0029]
(Explanation of operation of double chain stitch machine)
The operation of the double chain stitch sewing machine 100 configured as described above will be described.
First, the lower thread L is passed from the thread supply source to the looper 104 in a state where the lower thread L is inserted into the lower thread holding holes 12c and 12d of the U-shaped plate 12 of the lower thread holding device 10 and the elongated hole 13a of the guide frame 13.
When sewing starts in this state, the looper 104 reciprocates along the Y-axis direction in accordance with the vertical movement of the sewing needle, and the cloth feed 103 moves the fabric at the predetermined feed pitch in the X-axis direction. Send along. Thereby, the lower thread L is inserted into the loop of the upper thread, and the upper thread is inserted into the loop of the lower thread L, and the sewing operation is performed by repeating these. Further, the lower thread L protrudes between the lower thread holding holes 12c and 12d of the U-shaped plate 12 by the pair of lower thread cam plates 61 and 61 so as to bend along the elongated hole 13a at the same period as the reciprocating period of the looper 104. It is. Thereby, every time a loop is formed in the lower thread L, tension is applied to the lower thread L, so that the loop is eliminated and a knot is formed.
[0030]
(Effect of lower thread cam support device)
Then, when the lower thread L has unexpectedly cut at any position between the thread supply source and the sewing position, the thread end portion due to the cutting is supported by the lower thread cam plate 61 and the rotary sleeve body 21 and the bearing. Even when the body 22 is pulled to the lower shaft 66 side, the lid body 24 blocks the opening 22a of the bearing body 22, so that the bundle of wound lower threads L enters from the opening 22a. Thus, it is possible to effectively prevent the deformation of the valve body 23a of the oil seal 23.
Further, since the lower shaft 66 is covered with the covering cylindrical portion 24b of the lid body 24 that does not perform the rotating operation, it is possible to effectively suppress the situation in which the lower thread L is caught in the lower shaft 66 in the first place.
Further, since the coated cylindrical portion 24b is set to have a length such that the tip portion penetrates to the opening 21a of the rotating sleeve body 21, the outer peripheral surface of the lower shaft 66 is between the bearing body 22 and the rotating sleeve body 21. Therefore, the possibility that the cut end portion of the lower thread L is in contact with the lower shaft 66 can be sufficiently reduced, and the lower thread L can be more effectively prevented from being caught.
By these actions, it is possible to effectively prevent lubricating oil leakage and effectively avoid oil scattering, bobbin thread and contamination of the sewing object.
[0031]
If the sewing machine is not enlarged, the inner diameter of the opening 21a of the rotary sleeve 21 is set large so that the lower thread L can be prevented from being caught, and the bearing 22 on the rotary sleeve 21 side is set. It is also possible to extend the end and enter the opening 21a. However, in the sewing machine in which one end portion of the bed portion 101 shown in this embodiment is a cylinder shape or a narrowed shape, it is essential to reduce the outer diameter of the lower thread cam plate 61 and the rotating sleeve body 21. It is almost impossible to set the inner diameter of the opening 21a of the rotating sleeve body 21 so large. Therefore, like the cover body 24 of the present embodiment, the coated cylindrical portion 24b having an outer diameter closer to the outer diameter of the lower shaft 66 is provided, and the opening portion 21a of the rotating sleeve body 21 is also set to have a smaller inner diameter. It is possible to prevent the lower thread L from being caught while reducing the size of each component.
Accordingly, the lower thread cam support device 20 having the above-described configuration can more appropriately cope with one end portion of the bed portion 101 being a cylinder-shaped or narrowed sewing machine, and effectively eliminates lubricating oil leakage. Is possible.
[0032]
(Other)
The bearing body 22 has a structure including an opening 22a and an oil seal 23 inside. However, as shown in FIG. 7, the bearing body 22 has an engagement hole 106a provided in a machine frame 106 as a frame. In addition, an oil seal 23 may be provided in the engagement hole, and the opening on the rotating sleeve body 21 side of the engagement hole 106a may be closed by the lid body 24. In this case, a sealed space is formed between the bearing body 22 and the oil seal 23, and the lubricating oil supplied from the lubricating oil supply hole 22b accumulates in the sealed space and is discharged from the oil discharge hole 22c.
Further, since the opening of the engagement hole 106a of the machine frame 106 is closed by the lid body 24, the cut lower thread L is prevented from entering the engagement hole 106a, and the deformation of the oil seal 23 is prevented. Therefore, it is possible to effectively prevent leakage of lubricating oil and effectively avoid oil scattering, bobbin thread, and contamination of the sewing object.
[0033]
【The invention's effect】
According to the first aspect of the present invention, since the lid is provided at the opening of the bearing body, the opening of the lower thread that is cut and wound into the rotating shaft between the rotating sleeve body and the bearing body and bundled Effectively prevents the oil seal from intruding and prevents deformation of the oil seal, effectively preventing leakage of lubricating oil and effectively avoiding oil scattering, bobbin thread, and contamination of the sewing object. It becomes possible to do.
[0034]
According to the second aspect of the present invention, since the lid is provided in the engagement hole of the frame, the lower thread is engaged in a bundle by being cut and wound around the rotation shaft between the rotation sleeve body and the frame. Effectively prevents holes from entering and prevents deformation of the oil seal, effectively preventing leakage of lubricating oil and effectively avoiding oil scattering, bobbin thread and contamination of sewing objects. It becomes possible to do.
[0035]
According to the third aspect of the present invention, since the bearing body is fixedly supported by the frame, the bearing body or the lid body supported by the frame does not cause a rotation operation. Therefore, the cut lower thread does not come into contact with the lid body, and the occurrence of the lower thread can be suppressed. Accordingly, it is possible to more effectively prevent leakage of lubricating oil, and more effectively avoid oil scattering, lower thread, and contamination of the sewing object.
[0036]
In the invention according to claim 4, since the lid includes a cylindrical portion that covers the rotating shaft, the contact between the lower thread that has been cut and the rotating shaft is suppressed, and the lower thread winding itself is effectively suppressed. Can do. Therefore, lubricating oil leakage can be further effectively prevented, and oil scattering, lower thread, and contamination of the sewing object can be more effectively avoided.
[0037]
According to the fifth aspect of the present invention, since the cylindrical portion of the lid body penetrates to the opening portion of the rotating sleeve body, the exposure of the rotating shaft is further reduced, and the lower thread winding can be more effectively suppressed. it can. Accordingly, it is possible to more effectively prevent leakage of lubricating oil and more effectively avoid oil scattering, lower thread, and contamination of the sewing object.
[0038]
Since the boss part provided in the cover body fits into the opening part of the bearing body, the invasion of the lower thread from between the cover body and the bearing body can be effectively reduced, Can be further suppressed. Accordingly, it is possible to more effectively prevent leakage of lubricating oil and more effectively avoid oil scattering, lower thread, and contamination of the sewing object.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a state in which a lower thread feeding device according to an embodiment is incorporated in a sewing machine.
2 is a perspective view of a configuration around a cylinder-shaped portion of the sewing machine disclosed in FIG. 1; FIG.
3 is a perspective view of a configuration around a cylinder-shaped portion as viewed from a direction different from FIG. 2. FIG.
FIG. 4 is an exploded perspective view of the lower thread cam support device.
FIG. 5 is an exploded perspective view of the lower thread cam support device viewed from different directions.
FIG. 6 is a cross-sectional view of the lower thread cam support device along the lower shaft.
FIG. 7 is a cross-sectional view of a lower thread cam support device equipped with an oil seal and a lid in an engagement hole provided in the machine frame.
[Explanation of symbols]
10 Lower thread holding device
20 Lower thread cam support device
21 Rotating sleeve body
21a opening
22 Bearing body
22a opening
23 Oil seal
23a Disc
24 Lid
24a Insert cylindrical part (boss part)
24b Covered cylindrical part
24c bowl
24d center hole
25 Spacer
26 Fixing screw
61 Lower thread cam plate
66 Lower shaft (rotating shaft)
100 Double chain stitch sewing machine
104 loopers
106 Airframe
106a engagement hole

Claims (6)

A lower thread cam support device provided between a thread supply source and a sewing position,
A rotating sleeve body that supports a lower thread cam plate that rotates in sliding contact with an outer edge of the lower thread supplied to the sewing position and is fixed to a rotating shaft that rotates in conjunction with a sewing machine motor;
A bearing body of the rotating shaft disposed adjacent to the lower thread cam plate;
An oil seal disposed inside an opening formed around the rotary shaft from the lower thread cam plate side end surface of the bearing body,
A lower thread cam support device for a sewing machine having a center hole through which the rotating shaft is inserted and a lid for closing the opening of the bearing body. A lower thread cam support device provided between a thread supply source and a sewing position,
A rotating sleeve body that supports a lower thread cam plate that rotates in sliding contact with an outer edge of the lower thread supplied to the sewing position and is fixed to a rotating shaft that rotates in conjunction with a sewing machine motor;
A bearing body of the rotating shaft provided in an engagement hole of the frame adjacent to the lower thread cam plate;
An oil seal disposed inside the engagement hole,
A lower thread cam support device for a sewing machine having a central hole for inserting the rotation shaft and a lid for closing the engagement hole. 3. The lower thread cam support device for a sewing machine according to claim 1, wherein the bearing member is fixedly supported on the frame in a state where the rotation of the rotating shaft is allowed. 4. The lower thread cam support device for a sewing machine according to claim 1, wherein the lid body includes a cylindrical portion that covers at least a peripheral surface of the rotating shaft from the bearing body to the rotating sleeve body. . Providing an opening formed around the rotating shaft from the bearing body side end surface of the rotating sleeve body;
5. The lower thread cam support device for a sewing machine according to claim 4, wherein the cylindrical portion of the lid body has a length that penetrates into the opening of the rotary sleeve body. 6. The lower thread cam support device of a sewing machine according to claim 1, wherein the lid body includes a boss portion that fits into an opening portion of the bearing body or the engagement hole.

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