Sewing machine

Abstract

A sewing machine (1) is provided with: a needle bar (6) which holds a sewing machine needle (4) and which drops a sewing object (MS) by moving up and down; a needle plate (7) which is arranged below the needle rod (6) and used for supporting the sewing object (MS) from the lower part; a lower feeding mechanism (9) which conveys the sewing object (MS) supported by the needle plate (7) from the lower side; and a kettle (13) which is arranged below the needle plate (7) and supplies the lower thread to the sewing object (MS). The lower feeding mechanism (9) comprises a feeding tooth (31) which enables the sewing object (MS) to feed and move; a feed tooth table (32) that holds the feed teeth (31) and moves along a feed trajectory; and a receiving member (33) which is provided on the feed gear table (32) and is disposed laterally with respect to the needle drop path of the sewing machine needle (4). The receiving member (33) has a receiving surface (34) facing the needle drop path (NP) and capable of position adjustment in an adjustment direction approaching or separating from the needle drop path (NP).

Description

TECHNICAL FIELD

[0001] The present application relates to a sewing machine. BACKGROUND

[0002] A sewing machine is disclosed in Patent Literature 1, which feeds a sewing object by a feed dog while performing a needle drop for the sewing object by a sewing needle, and performs sewing by winding a lower thread on an upper thread with a horizontal bobbin.

[0003] Patent Literature 1: Japanese Patent No. 4913575 SUMMARY

[0004] In a case where sewing of a thick sewing object or sewing of a hard sewing object such as a leather material or a resin material is performed, the sewing machine needle is sometimes bent at the time of needle drop. If the sewing machine needle is bent, the position of the needle tip after the sewing object is penetrated deviates from a standard position. Therefore, if the sewing machine needle is bent, sewing defects such as skipping of a part of a stitch or breakage of a thread occur. Here, skipping refers to a case where a stitch cannot be formed because a lower thread is not wound on an upper thread. There is a demand for achieving stable sewing even in a condition where the sewing machine needle is bent.

[0005] An object of the present application is to achieve stable sewing even in a condition where the sewing machine needle is bent.

[0006] According to one embodiment of the present application, there is provided a sewing machine including a needle bar that holds a sewing machine needle and performs a needle drop for a sewing object by moving up and down, a needle plate that supports the sewing object from below under the needle bar, a lower feed mechanism that feeds the sewing object supported by the needle plate from below, and a bobbin that is disposed below the needle plate and supplies a lower thread to the sewing object, the lower feed mechanism including a feed dog that moves the sewing object in a feed track, a feed dog table that holds the feed dog and moves along the feed track, and a receiving member that is provided to the feed dog table and disposed laterally with respect to a needle drop path of the sewing machine needle, the receiving member having a receiving surface that faces the needle drop path and is positionally adjustable in an adjustment direction in which the receiving surface approaches or separates from the needle drop path.

[0007] EFFECT OF THE INVENTION

[0008] According to the present application, stable sewing can be achieved even in a condition where the sewing machine needle is bent. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1This is a perspective view of the sewing machine according to the embodiment, viewed from the upper left rear.

[0010] Figure 2 This is an enlarged oblique view taken from the upper left rear, showing the interior of the sewing machine frame according to the embodiment.

[0011] Figure 3 This is a schematic diagram used to illustrate the movement of the sewing machine needle and valve.

[0012] Figure 4 This is a schematic diagram used to illustrate the feeding mechanism of a sewing machine.

[0013] Figure 5 This is a perspective view of the lower feed mechanism, viewed from the upper left rear.

[0014] Figure 6 This is a perspective view of the lower feed mechanism, viewed from the upper right rear.

[0015] Figure 7 This is a top view showing the supporting components mounted on the feed gear table.

[0016] Figure 8 This is a right-side view showing the bottom feed mechanism and the sewing machine needle.

[0017] Figure 9 It is a sectional view taken from the rear to the front, showing the lower feed mechanism, sewing machine needle, and valve.

[0018] Figure 10 This is a schematic diagram showing a scale representation without any supporting components.

[0019] Figure 11 This is a schematic diagram illustrating this embodiment with a supporting component. Detailed Implementation

[0020] Below, refer to the appendix. Figure 1 The implementation method will be described below. In this implementation method, an XYZ orthogonal coordinate system is set, and the positional relationships between the various parts will be described with reference to this XYZ orthogonal coordinate system. This XYZ orthogonal coordinate system is about... Figures 1 to 11The relative directions set for the sewing machine 1 illustrated herein are as follows: The direction parallel to the X-axis within the specified plane is defined as the X-axis direction. The direction parallel to the Y-axis within the specified plane and orthogonal to the X-axis is defined as the Y-axis direction. The direction parallel to the Z-axis and orthogonal to the specified plane is defined as the Z-axis direction. Furthermore, the direction of rotation or tilting centered on the X-axis is defined as the θX direction. The direction of rotation or tilting centered on the Y-axis is defined as the θY direction. The direction of rotation or tilting centered on the Z-axis is defined as the θZ direction. Additionally, the plane including the X-axis and Y-axis is appropriately referred to as the XY plane. The plane including the X-axis and Z-axis is appropriately referred to as the XZ plane. The plane including the Y-axis and Z-axis is appropriately referred to as the YZ plane. The XY plane is parallel to the specified plane. The XY plane, XZ plane, and YZ plane are each orthogonal to the specified plane.

[0021] In this embodiment, the XY plane is assumed to be parallel to the horizontal plane. The horizontal direction includes the front-back direction and the left-right direction. Furthermore, the statement "the XY plane is parallel to the horizontal plane" is not limited to the XY plane being parallel to the horizontal plane. In this invention, the XY plane may also be inclined relative to the horizontal plane.

[0022] Additionally, the X-axis is the forward / backward direction. The Y-axis is the left / right direction. The Z-axis is the up / down direction. The +X direction is the forward direction, and the -X direction is the backward direction. The +Y direction is the left direction, and the -Y direction is the right direction. The +Z direction is the up direction, and the -Z direction is the down direction.

[0023] [Overview of Sewing Machines]

[0024] Figure 1 This is a perspective view of the sewing machine 1 according to the embodiment, viewed from the upper left rear. Figure 1 The illustration only shows the main structure of sewing machine 1, omitting details. In this embodiment, sewing machine 1 is an industrial sewing machine. Sewing machine 1 is a so-called flat sewing machine that forms a stitch by winding an upper thread and a lower thread together. Figure 1 As shown, the sewing machine 1 has a sewing machine frame 3.

[0025] The sewing machine frame 3 has an arm 3A, a base 3B, a base 3C, and a head 3D. The arm 3A is longer in the left-right direction of the sewing machine 1. The base 3B is positioned below the arm 3A. The base 3B is longer in the left-right direction of the sewing machine 1. The base 3B is positioned opposite the arm 3A in the vertical direction. The base 3C is positioned to connect the right end of the arm 3A to the base 3B. The base 3C is longer in the vertical direction of the sewing machine 1. The head 3D is located at the left end of the arm 3A. The head 3D protrudes downwards from the left end of the arm 3A.

[0026] like Figure 1As shown, the sewing machine 1 has a thread tension lever 5, a needle bar 6, a needle plate 7, a presser foot 8, a thread regulator, a lower feed mechanism 9, a sewing machine motor 10, a belt wheel 11, an upper feed section 12, and a bobbin 13 (see Figure 2 ). In addition, the sewing machine 1 is provided with a controller that controls each section of the sewing machine 1, and a pedal and an operation panel that accept operation input to the sewing machine 1.

[0027] Figure 2 is an enlarged oblique view from the upper left rear that shows the inside of the sewing machine frame 3 according to the present embodiment. In Figure 2 , only the main configuration is shown, and details are omitted.

[0028] As shown in Figure 1 and Figure 2 , the needle bar 6 holds the sewing machine needle 4. The needle bar 6 holds the sewing machine needle 4 in such a manner that the sewing machine needle 4 becomes parallel to the Z-axis. The needle bar 6 reciprocates in the up-and-down direction. The needle bar 6 is supported by the head 3D. The needle bar 6 moves up and down, thereby dropping the sewing machine needle 4 to the sewing object MS. The sewing machine needle 4 has a thread hole through which the upper thread UT (see Figure 3 ) passes. The sewing machine needle 4 holds the upper thread UT on the inner surface of the thread hole. The needle bar 6 reciprocates in the up-and-down direction, whereby the sewing machine needle 4 reciprocates in the up-and-down direction in a state in which the upper thread UT is held. In addition, the needle bar 6 not only reciprocates in the up-and-down direction, but also reciprocates in the front-and-rear direction (X-axis direction). The needle bar 6 moves in a trajectory that links with the operation of the lower feed mechanism 9 and the operation of the upper feed section 12, by a combination of up-and-down movement and front-and-rear movement. By the movement of the needle bar 6, the sewing machine needle 4 moves in a prescribed needle feed trajectory in the XZ plane.

[0029] The thread tension lever 5 (see Figure 1 ) supplies the sewing machine needle 4 with the upper thread UT. The thread tension lever 5 reciprocates in the up-and-down direction. The thread tension lever 5 is supported by the arm 3A. The thread tension lever 5 reciprocates in the up-and-down direction in a state in which the upper thread UT is held. The thread tension lever 5 has a holding hole through which the upper thread UT passes. The thread tension lever 5 holds the upper thread UT on the inner surface of the holding hole. The thread tension lever 5 reciprocates in the up-and-down direction, whereby the upper thread UT used for sewing of the sewing object MS is drawn out or the upper thread UT is lifted. The thread regulator is between the thread tension lever 5 and the needle bar 6, and imparts tension to the upper thread UT supplied to the sewing machine needle 4. The thread regulator is supported by the head 3D.

[0030] The needle plate 7 is disposed below the needle bar 6. The needle plate 7 supports the sewing object MS from below. The needle plate 7 supports the sewing object MS below the needle bar 6. The sewing machine needle 4 held by the needle bar 6 opposes the needle plate 7. The needle plate 7 has an opening through which the feed teeth 31 of the lower feed mechanism 9 can pass.

[0031] The presser foot 8 presses down on the sewing object MS, supported by the needle plate 7, from above. The presser foot 8 is positioned around at least a portion of the sewing machine needle 4. The presser foot 8 is fixed to the presser foot bar 8A (see reference). Figure 2 The presser foot 8A is supported by the head 3D. The presser foot 8A is movable in the vertical direction. The presser foot 8A presses the workpiece MS from above by the elastic force generated by a pressing spring located within the head 3D. The presser foot 8 has a pair of branching pressing plates at its front end that contacts the workpiece MS. One pressing plate is positioned relative to the sewing machine needle 4 in the +Y direction, and the other pressing plate is positioned relative to the sewing machine needle 4 in the -Y direction.

[0032] The lower feed mechanism 9 is located below the needle plate 7. The lower feed mechanism 9 conveys the workpiece MS, supported by the needle plate 7, from below. The lower feed mechanism 9 includes feed teeth 31 and a feed tooth platform 32. The feed teeth 31 move the workpiece MS forward. The feed teeth 31 are located below the needle plate 7. Sawtooth-shaped teeth are formed on the upper surface of the feed teeth 31 to increase the frictional resistance between the feed teeth and the workpiece MS. The feed tooth platform 32 holds the feed teeth 31. The feed tooth platform 32 moves (oscillates) in conjunction with the needle bar 6. The feed teeth 31 move along a predetermined feed trajectory, entering and exiting through an opening in the needle plate 7, accompanying the movement of the feed tooth platform 32. When conveying the workpiece MS, at least a portion of the feed teeth 31 protrudes upward from the upper surface of the needle plate 7 through the opening.

[0033] The upper feed section 12 is positioned above the needle plate 7. The upper feed section 12 feeds the workpiece MS, supported by the needle plate 7, from above. The upper feed section 12 is positioned around at least a portion of the sewing machine needle 4. The upper feed section 12 is located between a pair of pressing plates located at the front end of the presser foot 8. The upper feed section 12 is fixed to the lower end of the upper feed bar 12A. The upper feed bar 12A is supported by the head 3D. The upper feed bar 12A moves (oscillates) in conjunction with the needle bar 6. The upper feed section 12 moves along a predetermined upper feed trajectory, accompanying the movement of the upper feed bar 12A. Serrated teeth are formed on the lower surface of the upper feed section 12 to increase the frictional resistance between it and the workpiece MS.

[0034] The vessel 13 supplies thread to the object being sewn, MS. The vessel 13 is positioned below the feed teeth 31. In this embodiment, the vessel 13 is a so-called horizontal vessel with its axis of rotation facing the Z-axis. That is, the vessel 13 is capable of rotating in the θZ direction. The vessel 13 has: an inner vessel housing a spool for holding the thread; and an outer vessel that rotates in the θZ direction. The vessel 13 is supported by a vessel holding platform 14.

[0035] Sewing machine motor 10 (reference) Figure 1) generates power for operating each of the needle bar 6, the feed dog 31, the upper feed 12, and the bobbin 13. The sewing machine motor 10 generates power for moving the needle bar 6 in a needle feed trajectory. The sewing machine motor 10 generates power for rotating the bobbin 13 in the θZ direction. The sewing machine motor 10 generates power for moving the feed dog 31 in a feed trajectory. The sewing machine motor 10 generates power for moving the upper feed 12 in an upper feed trajectory. The sewing machine motor 10 includes a pulse motor. The sewing machine motor 10 is supported at a right portion of the arm 3A.

[0036] The sewing machine motor 10 is coupled with the needle bar 6, the feed dog 31, the upper feed 12, and the bobbin 13 via a sewing machine power transmission mechanism. The sewing machine power transmission mechanism operates each of the needle bar 6, the feed dog 31, the upper feed 12, and the bobbin 13 based on the power generated by the sewing machine motor 10. The sewing machine power transmission mechanism transmits the power generated by the sewing machine motor 10 to the needle bar 6, the feed dog 31, the upper feed 12, and the bobbin 13, respectively.

[0037] Specifically, an upper shaft extending in the Y-axis direction is arranged inside the arm 3A. The sewing machine motor 10 is coupled with an end portion of the upper shaft on the -Y side. An end portion of the upper shaft on the +Y side is coupled with the needle bar 6 via a swing link mechanism arranged inside the head 3D. The upper shaft is rotated by the operation of the sewing machine motor 10. The power generated by the sewing machine motor 10 is transmitted to the needle bar 6 via the upper shaft and the swing link mechanism. The needle bar 6 and the sewing machine needle 4 held by the needle bar 6 are reciprocated (swung) in the up-down direction and the front-back direction in a needle feed trajectory based on the power generated by the sewing machine motor 10.

[0038] In addition, the upper shaft is coupled with the upper feed bar 12A via the swing link mechanism arranged inside the head 3D. The power generated by the sewing machine motor 10 is transmitted to the upper feed bar 12A via the upper shaft and the swing link mechanism. The upper feed bar 12A and the upper feed 12 held by the upper feed bar 12A are reciprocated (swung) in the up-down direction and the front-back direction in an upper feed trajectory based on the power generated by the sewing machine motor 10.

[0039] A timing belt extending in the Z-axis direction is arranged inside the base 3C. In addition, a base shaft 20 extending in the Y-axis direction is arranged inside the base 3B (refer to Figure 2 ). Pulleys are arranged at each of the upper shaft and the base shaft 20. The timing belt is stretched over the pulley arranged at the upper shaft and the pulley arranged at the base shaft 20, respectively. The upper shaft and the base shaft 20 are coupled via the timing belt.

[0040] As Figure 2As shown, the base shaft 20 is connected to the bobbin shaft provided to the bobbin holding table 14 in the Z-axis direction via a bevel gear so as to be able to transmit power. By the operation of the sewing machine motor 10, the upper shaft and the base shaft 20 each rotate. The power generated by the sewing machine motor 10 is transmitted to the bobbin 13 via the upper shaft, the synchronous belt, the base shaft 20, and the bobbin shaft. Thus, the bobbin 13 rotates in the θZ direction in synchronization with the movement of the needle bar 6 to supply the lower thread to the sewing object MS.

[0041] A pair of lower shafts 21A, 21B extending in the Y-axis direction are arranged inside the base 3B. The lower shafts 21A, 21B are connected to the upper shaft via cam mechanisms passing through inside the base 3C, respectively. The lower shaft 21A is arranged at the front side (+X direction) inside the base 3B. The lower shaft 21A is connected to the front side end of the feed rack 32 via an arm portion 22A extending in the radial direction. The lower shaft 21B is arranged at the rear side (-X direction) inside the base 3B. The lower shaft 21B is connected to the rear side end of the feed rack 32 via an arm portion 22B extending in the radial direction. By the operation of the sewing machine motor 10, the upper shaft rotates, and the lower shafts 21A, 21B each perform periodic motion via the cam mechanisms. The power generated by the sewing machine motor 10 is transmitted to the feed rack 32 via the upper shaft, the cam mechanisms, the lower shafts 21A, 21B. Thus, the feed rack 32 swings in synchronization with the movement of the needle bar 6. The feed teeth 31 reciprocate (swing) in the up-down direction and the front-rear direction with the feed track in conjunction with the swinging of the feed rack 32.

[0042] With the above-described structure, the sewing machine 1 sews the sewing object MS by the cooperative action of the sewing machine needle 4 held by the needle bar 6 and the bobbin 13. The sewing machine 1 transports the sewing object MS in the front direction (+X direction) by the cooperative action of the upper feed portion 12, the feed teeth 31, and the sewing machine needle 4.

[0043] Figure 3 is a schematic view for explaining the action of the sewing machine needle 4 and the bobbin 13. At the time of sewing, the sewing machine needle 4 holding the upper thread UT is lowered in the -Z direction to pass through the sewing object MS (refer to Figure 1 ) from above. The sewing machine needle 4 is lowered to the lower limit position in the Z-axis direction and then is raised. If the sewing machine needle 4 starts to be raised, the upper thread UT is slackened between the eyelet of the sewing machine needle 4 and the sewing object MS, and a thread loop of the upper thread UT is formed. The bobbin 13 rotates in the Zθ direction in conjunction with the movement of the sewing machine needle 4, and the tip 13A of the outer bobbin enters the thread loop of the upper thread UT by the rotation to catch the thread loop. The bobbin 13 continues to rotate even after the thread loop of the upper thread UT is caught, and the inner bobbin passes through the thread loop. Thus, the bobbin 13 causes the lower thread (not shown) pulled out from the inner bobbin to be inserted through and wound in the thread loop of the upper thread UT, and a stitch is formed.

[0044] Figure 4is a schematic view for explaining conveyance of the sewing machine 1. At the time of sewing, the feed dog 31 swings with a lower feed trajectory, the upper feed portion 12 swings with an upper feed trajectory, and the needle bar 6 (sewing machine needle 4) swings with a needle feed trajectory in the XZ plane. These lower feed trajectory, upper feed trajectory, and needle feed trajectory are cyclic trajectories in the conveyance direction (X axis direction), for example, elliptical trajectories. The upper feed portion 12 and the feed dog 31 sandwich the sewing object MS from above and below, and advance in the conveyance direction (+X direction), thereby moving the sewing object MS in the conveyance direction. At this time, the needle bar 6 (sewing machine needle 4) advances in the conveyance direction (+X direction) in conjunction with the upper feed portion 12 and the feed dog 31 while keeping the sewing machine needle 4 penetrating the sewing object MS. As described above, the sewing machine 1 is a comprehensive feed sewing machine that makes the feed dog 31 of the lower feed mechanism 9, the upper feed portion 12, and the needle bar 6 act with the feed trajectories in conjunction with each other. The comprehensive feed is a feed method that can increase the feed force of the sewing object MS, and is suitable for sewing of a sewing object MS having a relatively large thickness or the like.

[0045] The controller controls the sewing machine motor 10. The controller has a processor such as a CPU (Central Processing Unit), a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), and an input / output interface including an input / output circuit capable of inputting and outputting signals and data.

[0046] The pedal is operated by an operator of the sewing machine 1. The operator operates the pedal by foot. An operation signal generated by operation of the pedal is sent to the controller. The sewing machine motor is driven or stopped based on the operation state of the pedal.

[0047] The operation panel includes a flat panel display and a touch panel. The operation panel is operated by an operator of the sewing machine 1. The operation panel is provided to at least a part of the sewing machine stand 3. The operator operates the operation panel by finger, and makes settings related to the operation of the sewing machine 1.

[0048] [Lower Feed Mechanism]

[0049] Next, the configuration of the lower feed mechanism 9 will be described in detail. Figure 5 is a perspective view showing the lower feed mechanism 9 as viewed from the upper left rear. Figure 6 is a perspective view showing the lower feed mechanism 9 as viewed from the upper right rear.

[0050] As Figure 5 and Figure 6As shown, the feed tooth 31 is fixed to the upper end of the feed tooth table 32 in the X-axis direction. The feed tooth 31 has: a fixing part 31A, which is mounted on the feed tooth table 32; a wall part 31B, which stands upright from the fixing part 31A; and an upper surface part 31C, which is provided at the upper end of the wall part 31B and contacts the sewing object MS. The wall part 31B is located at the right end of the fixing part 31A. The wall part 31B has an upright plate-like shape along the XZ plane. The upper surface part 31C protrudes to the right (in the -Y direction) from the upper end of the wall part 31B. The upper surface part 31C is provided with serrated teeth 31D and needle holes 31E. The needle holes 31E pass through the upper surface part 31C vertically at a position offset to the right (in the -Y direction) compared to the wall part 31B. As the sewing machine needle 4 descends, the sewing machine needle 4, which passes through the object MS being sewn, passes through the needle hole 31E.

[0051] The feed gear table 32 is a plate-shaped component extending in the front-rear direction of the lower feed mechanism 9. A connecting portion 32A to the lower shaft 21A (arm 22A) is provided at the front end of the feed gear table 32. A connecting portion 32B to the lower shaft 21B (arm 22B) is provided at the rear end of the feed gear table 32. A holding portion 32C is provided between the connecting portions 32A and 32B in the front-rear direction to hold the feed gear 31. A fixing portion 31A of the feed gear 31 is mounted on the upper surface of the holding portion 32C.

[0052] Here, in this embodiment, as Figure 6 As shown, the lower feed mechanism 9 includes a receiving member 33. The receiving member 33 is disposed on the feed gear table 32. The receiving member 33 is disposed on the side of the holding portion 32C of the feed gear table 32. Furthermore, the receiving member 33 is disposed to the side relative to the needle path NP of the sewing machine needle 4. Additionally, the receiving member 33 is disposed directly below the feed gear 31. The needle path NP is the relative movement path (track) of the sewing machine needle 4 relative to the lower feed mechanism 9. The needle path NP is a path along the Z-axis passing through the needle hole 31E. The receiving member 33 has a receiving surface 34 opposite to the needle path NP. The receiving surface 34 is the side of the receiving member 33 in the right direction (-Y). The position of the receiving surface 34 can be adjusted in an adjustment direction that approaches or separates from the needle path NP. In this embodiment, the adjustment direction of the receiving surface 34 is the Y-axis direction.

[0053] Figure 7 This is a top view showing the supporting component 33 mounted on the feed gear table 32. Figure 7The state after the feed teeth 31 are detached from the feed tooth base 32 is shown in FIG. 1. The receiving member 33 has a first portion 33A, a second portion 33B, and a third portion 33C. The receiving member 33 is substantially in the shape of an inverted U through the first portion 33A, the second portion 33B, and the third portion 33C. The receiving member 33 is a single article formed of the first portion 33A, the second portion 33B, and the third portion 33C. The receiving member 33 is made of metal, for example, composed of spring steel.

[0054] The first portion 33A constitutes the side surface of the left side (+Y side) of the receiving member 33 and extends linearly in the front-rear direction. The first portion 33A is the portion fixed to the feed tooth base 32. Two through holes (non-tapped holes) for inserting the mounting screws 35 therethrough are formed in the first portion 33A. The mounting screws 35 inserted through the respective through holes are loaded to the screw holes provided in the side surface of the holding portion 32C of the feed tooth base 32. The receiving member 33 is fastened to the side surface of the holding portion 32C by the two mounting screws 35 in the first portion 33A. In addition, in the first portion 33A, an insertion hole 33D for inserting the adjustment member 36 (refer to FIG. 2) described later therethrough is formed between the two through holes. The first portion 33A is connected to the third portion 33C at the front end portion. Figure 5

[0055] The second portion 33B constitutes the side surface of the right side (-Y side, needle drop path NP side) of the receiving member 33 and extends linearly in the front-rear direction. The receiving surface 34 is formed in the second portion 33B. That is, the outer surface of the right side (-Y side) of the second portion 33B is the receiving surface 34. The second portion 33B extends rearward (-X direction) from the third portion 33C. The second portion 33B extends at least to the position further rearward (-X direction) than the needle drop path NP. That is, the receiving surface 34 is formed in the range from the position further +X side than the needle drop path NP to the position further -X side than the needle drop path NP. In the example of FIG. 1, the length of the second portion 33B in the X direction is shorter than the length of the first portion 33A in the X direction. Figure 7

[0056] The third portion 33C constitutes the side surface of the front side (+X side) of the receiving member 33 and extends linearly in the left-right direction. The third portion 33C connects the first portion 33A and the second portion 33B. The left end portion of the third portion 33C is connected to the first portion 33A, and the right end portion of the third portion 33C is connected to the second portion 33B.

[0057] Figure 8 ​​is a right side view of the lower feed mechanism 9 and the sewing machine needle 4. The receiving surface 34 is opposed to the side surface of the sewing machine needle 4 passing through the needle drop path NP in the Y-axis direction. The receiving member 33 is moved in the feed locus in the up-down direction and the front-rear direction together with the feed tooth 31 and the feed tooth holder 32. Also, the receiving member 33 is maintained in a state of being opposed to the side surface of the sewing machine needle 4 in the Y-axis direction in the vicinity of the lower dead point of the sewing machine needle 4. As shown in Figure 7 , the receiving surface 34 is disposed at a position separated in the +Y direction with respect to the needle drop path NP. In the case where the sewing machine needle 4 normally moves along the needle drop path NP, the receiving surface 34 does not come into contact with the sewing machine needle 4. In the case where the sewing machine needle 4 is bent to the feed tooth 31 side (i.e., the +Y direction) during sewing, the receiving surface 34 comes into contact with the bent sewing machine needle 4. Thus, the receiving surface 34 has a function of restricting the sewing machine needle 4 so as not to be bent by an amount more than an allowable amount. Further, the "bending" of the sewing machine needle 4 referred to herein is a deformation of a small deformation amount to the extent that the sewing machine needle 4 can be inserted and withdrawn to the needle hole 31E, and is a deformation within a range in which sewing can be continued.

[0058] As shown in Figure 7 , in the present embodiment, the interval CL in the adjustment direction (Y-axis direction) between the receiving surface 34 and the needle drop path NP (i.e., the sewing machine needle 4) can be adjusted in correspondence with the position of the receiving surface 34. The receiving member 33 is formed of spring steel or the like as described above, and has elasticity that enables the 2nd portion 33B to be displaced in the adjustment direction (Y-axis direction) by elastic deformation. Also, the lower feed mechanism 9 includes an adjustment member 36 that displaces the 2nd portion 33B in the adjustment direction (Y-axis direction). The receiving member 33 can displace the 2nd portion 33B in the adjustment direction (Y-axis direction) by the adjustment member 36, thereby adjusting the position of the receiving surface 34.

[0059] The adjustment member 36 is a feed screw that is loaded to the feed tooth holder 32 in abutment with the 2nd portion 33B, and is provided so as to be able to advance and retreat in the adjustment direction (Y-axis direction). As shown in Figure 5 , the adjustment member 36 is inserted to a screw hole formed in the holding portion 32C of the feed tooth holder 32 via the insertion hole 33D of the 1st portion 33A. The screw hole formed in the holding portion 32C penetrates the holding portion 32C in the Y-axis direction. As shown in Figure 6 and Figure 7 , the adjustment member 36 penetrates the holding portion 32C in the -Y direction, and abuts against the side surface of the +Y side of the 2nd portion 33B. The adjustment member 36 presses the 2nd portion 33B in the -Y direction.

[0060] Figure 7 The adjustment member 36 at the standard position is shown. In a natural state where the 2nd portion 33B is not pressed by the adjustment member 36, the 2nd portion 33B is in abutment with the receiving surface 34 of the receiving member 33 in the +Y direction. The adjustment member 36 is disposed so as to be able to press the 2nd portion 33B in the -Y direction. Figure 7The standard position is formed by bending towards the +Y side. Part 2 33B is configured such that by adjusting component 36 being pressed towards the -Y direction to the standard position. Figure 7 The position is shown. Rotating the adjusting member 36 within the screw hole of the retaining part 32C feeds the adjusting member 36 in the -Y direction, thereby deforming the second part 33B from its standard position in the -Y direction, allowing the bearing surface 34 to displace in the -Y direction. As a result, the gap CL between the bearing surface 34 and the needle path NP decreases. Conversely, if the adjusting member 36 is fed in the +Y direction from its standard position, the second part 33B elastically returns to its original position in the +Y direction, thereby displacing the bearing surface 34 in the +Y direction. As a result, the gap CL between the bearing surface 34 and the needle path NP increases.

[0061] Figure 9 This is a sectional view taken from the rear to the front, showing the lower feed mechanism 9, sewing machine needle 4, and feed plate 13. The bearing surface 34 can be adjusted between a position close to the needle path NP compared to the side surface 31F on the side of the needle path NP of the wall 31B, and a position far from the needle path NP compared to the side surface 31F of the feed tooth 31. In other words, the bearing surface 34 can be moved to a position closer to the -Y direction compared to the side surface 31F. Additionally, the bearing surface 34 can be moved to a position closer to the +Y direction compared to the side surface 31F.

[0062] Additionally, the sewing machine needle 4 may bend in the -Y direction during sewing. Therefore, as... Figure 3 As shown, the vessel 13 has a needle receiving portion 13B. When the sewing machine needle 4 bends in the -Y direction, this needle receiving portion 13B contacts the bent sewing machine needle 4 and restricts its bending to a tolerance limit. The needle receiving portion 13B is located on the outer vessel of the vessel 13 and rotates together with the tip 13A. The receiving surface 34 of the receiving member 33 is opposite to the needle receiving portion 13B of the vessel 13 in the adjustment direction (Y-axis direction). The receiving surface 34 is positioned on the +Y side relative to the needle drop path NP, and the needle receiving portion 13B is positioned on the -Y side relative to the needle drop path NP. Therefore, in the sewing machine 1, whether the sewing machine needle 4 bends in the +Y direction or in the -Y direction, its bending is limited to a tolerance range.

[0063] [effect]

[0064] Next, the function of the sewing machine 1 according to this embodiment will be explained. Figure 10 This is a comparative schematic diagram showing the situation without the support component 33. Figure 11is a schematic view of the present embodiment in which the receiving member 33 is provided. In typical cases, in the case where the thickness of the sewing object MS is thick, or in the case where the sewing object MS contains a hard material (leather or a resin material, etc.), the bending of the sewing machine needle 4 is caused by external force applied to the sewing machine needle 4 at the time of sewing. Assume that the sewing machine needle 4 bends in the +Y direction in which the lower feed mechanism 9 is arranged. As Figure 10 As in the comparative example, in the case where the receiving member 33 is not provided, the deformation of the sewing machine needle 4 cannot be prevented, and thus the gap D between the sewing machine needle 4 and the tip 13A becomes large. In this case, depending on the shape of the thread loop of the upper thread UT, the tip 13A can fail to catch the thread loop, resulting in failure of the entanglement of the upper thread UT and the lower thread. If the tip 13A fails to catch the thread loop, a needle skip or a breakage of the upper thread UT occurs at the needle drop position thereof. The needle skip refers to a case where a stitch is not formed.

[0065] In the comparative example, in order to suppress the occurrence of the needle skip or the breakage, for example, an adjustment method in which the positions of the bobbin 13 and the bobbin holder 14 are misaligned is considered. That is, the position of the tip 13A is adjusted in consideration of the amount of bending deformation of the sewing machine needle 4, and thus the adjustment is performed so that the gap D becomes appropriate. However, the position adjustment of the bobbin 13 and the bobbin holder 14 requires local disassembly of the connection site thereof with the sewing machine power transmission mechanism including the base shaft 20 or the bobbin shaft, and thus is troublesome and has a large work load.

[0066] Further, in the sewing machine 1, the sewing machine needle 4 is replaced with one having a different thickness (diameter) in accordance with the sewing object MS. The amount of bending deformation of the sewing machine needle 4 also varies depending on the thickness of the sewing machine needle 4 or the sewing object MS. That is, if the thickness of the sewing machine needle 4 is changed, the gap D between the sewing machine needle 4 and the tip 13A changes. Therefore, it can be necessary to perform the position adjustment work of the bobbin 13 and the bobbin holder 14 each time the thickness of the sewing machine needle 4 is changed.

[0067] In contrast to this, as shown in Figure 11 In the present embodiment, if the bending of the sewing machine needle 4 in the +Y direction occurs, the receiving surface 34 of the receiving member 33 comes into contact with the bent sewing machine needle 4. The sewing machine needle 4 is thereby prevented from being further bent and deformed by coming into contact with the receiving surface 34. The gap D between the sewing machine needle 4 and the tip 13A is prevented from becoming larger than the allowable range, and thus the possibility of the failure of the tip 13A to catch the thread loop of the upper thread UT is reduced.

[0068] Moreover, even in the case of replacing the sewing machine needle 4 with a needle of a different thickness (diameter), the gap CL between the receiving surface 34 and the needle drop path NP (sewing machine needle 4) can be adjusted simply by adjusting the amount of discharge of the adjustment member 36. That is, instead of adjusting the passing position of the tip 13A to match the amount of bending deformation of the sewing machine needle 4, the allowable range of the amount of bending deformation of the sewing machine needle 4 can be adjusted to match the passing position of the tip 13A. As a result, without performing position adjustment of the bobbin 13 and the bobbin holder 14, the occurrence of needle skipping or thread breakage can be suppressed simply by a simple adjustment operation of the position of the receiving surface 34.

[0069] [Effects]

[0070] As described above, the sewing machine 1 according to the present embodiment has a needle bar 6 that holds the sewing machine needle 4 and drops the needle to the sewing object MS by moving up and down, a needle plate 7 that supports the sewing object MS from below under the needle bar 6, a lower feed mechanism 9 that feeds the sewing object MS supported by the needle plate 7 from the lower side, and a bobbin 13 that is disposed below the needle plate 7 and supplies the sewing object MS with a lower thread. The lower feed mechanism 9 includes a feed tooth 31 that moves the sewing object MS in a feed direction, a feed tooth holder 32 that holds the feed tooth 31 and moves along a feed track, and a receiving member 33 that is provided to the feed tooth holder 32 and is disposed to the side with respect to the needle drop path NP of the sewing machine needle 4. The receiving member 33 has a receiving surface 34 that faces the needle drop path NP and is positionally adjustable in an adjustment direction (Y-axis direction) that approaches or separates with respect to the needle drop path NP.

[0071] According to the present embodiment, even in the case where bending of the sewing machine needle 4 occurs, by bringing the receiving surface 34 into contact with the bent sewing machine needle 4, the amount of bending deformation of the sewing machine needle 4 can be limited. Moreover, by positionally adjusting the receiving surface 34 with respect to the needle drop path NP, the allowable range of the amount of bending deformation of the sewing machine needle 4 can be adjusted to a range in which the occurrence of needle skipping or thread breakage can be suppressed. As a result, even in conditions in which bending of the sewing machine needle 4 is likely to occur, stable sewing can be achieved.

[0072] In this embodiment, the bearing member 33 has a first portion 33A fixed to the feed gear table 32, a second portion 33B having a bearing surface 34, and a third portion 33C connecting the first portion 33A and the second portion 33B. It also has elasticity that allows the second portion 33B to be displaced in the adjustment direction (Y-axis direction) through elastic deformation. The lower feed mechanism 9 includes an adjustment member 36 that displaces the second portion 33B in the adjustment direction (Y-axis direction). Thus, the position of the bearing surface 34 can be adjusted using a simple structure by utilizing the elastic deformation of the second portion 33B of the bearing member 33. Furthermore, even when the bearing surface 34 is displaced in the +Y direction away from the needle path NP, the positional shift of the bearing surface 34 can be suppressed by utilizing the elasticity (restoring force) of the second portion 33B.

[0073] In this embodiment, the adjusting member 36 is mounted on the feed gear table 32 in a manner that abuts against the second part 33B, and is a feed screw that can move forward and backward in the adjusting direction (Y-axis direction). Therefore, the position of the bearing surface 34 can be adjusted by a very simple operation that only adjusts the release amount of the feed screw. Thus, even when adjusting the position of the bearing surface 34 each time the thickness of the sewing machine needle 4 is changed, the workload and complexity of the adjustment operation can be reduced.

[0074] In this embodiment, the bearing surface 34 can be positioned between a position close to the needle path NP compared to the side surface 31F on the side of the needle path NP of the wall portion 31B, and a position far from the needle path NP compared to the side surface 31F. This significantly increases the position adjustment range of the bearing surface 34.

[0075] In this embodiment, the bearing surface 34 of the bearing member 33 is opposite to the needle bearing portion 13B of the vessel 13 in the adjustment direction (Y-axis direction). Therefore, in the case where the sewing machine needle 4 bends towards the feed tooth 31 side (+Y direction) and towards the vessel 13 side (-Y direction), the bending deformation of the sewing machine needle 4 can be limited to an acceptable range.

[0076] In this embodiment, the sewing machine 1 is a combined feed sewing machine in which the feed teeth 31 of the lower feed mechanism 9, the upper feed section 12, and the needle bar 6 operate along a feed trajectory that is linked to each other. This allows for increased feed force, enabling the sewing of thick objects MS. The sewing needle 4 is particularly prone to bending during the sewing of thick objects MS. Therefore, in the combined feed sewing machine, stable sewing can be achieved even when sewing thick materials where needle bending is likely to occur.

[0077] [Other Implementation Methods]

[0078] In the above embodiment, an example of a combined feed sewing machine 1 is shown, but the feeding method of the sewing machine is not particularly limited. The feeding method of the sewing machine may be only down feed, or it may be feed and needle feed, or it may be up and down feed (up feed and down feed), etc. Therefore, the sewing machine 1 may not be equipped with an up feed section 12, and the needle bar 6 may not move along the needle feed trajectory. The movement of the needle bar 6 may also be only up and down movement.

[0079] In the above embodiment, an example of a horizontal vessel 13 is shown, but the vessel can also be a vertical vessel with the rotation center axis facing the horizontal direction.

[0080] In the above embodiments, an example is shown where the position of the bearing surface 34 is adjusted by elastically deforming the bearing member 33; however, the structure for adjusting the position of the bearing surface 34 is not particularly limited. For example, a bearing member having a bearing surface can be mounted at the front end of a feed screw, and the bearing member can be moved horizontally in the adjustment direction corresponding to the release amount of the feed screw. Furthermore, the adjustment member is not limited to a feed screw; for example, it can be an eccentric cam that adjusts the position of the bearing member. Multiple insertion holes can be provided in the bearing member along the adjustment direction, and positioning pins inserted into these holes can be provided as adjustment members. An elongated hole along the adjustment direction can also be provided in the bearing member, and a screw can be provided as an adjustment member, inserted through the elongated hole, and the bearing member can be positionally adjusted and fastened within the forming range of the elongated hole.

[0081] The present invention includes the following methods. (1)

[0083] A sewing machine having: The needle bar holds the sewing machine needle and moves up and down to drop the needle onto the object being sewn. A needle plate that supports the object being sewn from below, located beneath the needle bar; A bottom feed mechanism that conveys the workpiece supported on the needle plate from below; and A feeder, positioned below the needle plate, supplies the thread to the object being sewn. The lower feed mechanism includes: Feed teeth that cause the object to be sewn to move forward; A feed gear table that holds the feed teeth and moves along the feed trajectory; and A receiving component, disposed on the feed table, is arranged to the side relative to the needle drop path of the sewing machine needle. The bearing component has a bearing surface opposite to the needle drop path and is positionally adjustable in an adjustment direction relative to the needle drop path, either close to or separate from it. (2)

[0085] According to the sewing machine described in (1), among which, The bearing member has: a first portion fixed to the feed gear table; a second portion having the bearing surface; and a third portion connecting the first portion and the second portion, and the bearing member has elasticity capable of displacing the second portion in the adjustment direction through elastic deformation. The lower feed mechanism includes an adjustment component that displaces the second part in the adjustment direction. (3)

[0087] According to the sewing machine described in (2), among which, The adjustment component is mounted on the feed gear table in a manner that abuts against the second part, and the feed screw is provided to move forward and backward in the adjustment direction. (4)

[0089] According to any one of (1) to (3), the sewing machine described therein, The feed tooth has: a fixing portion fixed to the feed tooth platform; a wall portion extending upward from the fixing portion; and an upper surface portion disposed at the upper end of the wall portion and in contact with the object to be sewn. The bearing surface can be positioned between a position close to the needle path compared to the side of the wall portion on the side of the needle path and a position far away from the needle path compared to the side of the wall portion. (5)

[0091] According to any one of (1) to (4), the sewing machine described therein, The vessel has a needle receiving part. The bearing surface of the bearing component is opposite to the needle bearing portion of the vessel in the adjustment direction. (6)

[0093] According to any one of (1) to (5), the sewing machine described therein, It also has an upper feed section that transports the sewing object supported on the needle plate from above. This sewing machine is an integrated feed sewing machine that causes the feed teeth, the upper feed section, and the needle bar of the lower feed mechanism to move along a feed trajectory that is linked to each other.

[0094] This application is based on Japanese Patent Application No. 2023-148190, filed on September 13, 2023, the contents of which are incorporated herein by reference.

Claims

1. A sewing machine, comprising: The needle bar holds the sewing machine needle and moves up and down to drop the needle onto the object being sewn. A needle plate that supports the object being sewn from below, located beneath the needle bar; A bottom feed mechanism that conveys the sewing object supported by the needle plate from below; and A feeder, positioned below the needle plate, supplies the thread to the object being sewn. The downfeed mechanism includes: Feed teeth that cause the object to be sewn to move forward; A feed gear table that holds the feed teeth and moves along the feed trajectory; and A receiving component, disposed on the feed table, is arranged to the side relative to the needle drop path of the sewing machine needle. The bearing component has a bearing surface opposite to the needle drop path and is positionally adjustable in an adjustment direction relative to the needle drop path, either close to or separate from it.

2. The sewing machine according to claim 1, wherein, The bearing member has: a first portion fixed to the feed gear table; a second portion having the bearing surface; and a third portion connecting the first portion and the second portion, and the bearing member has elasticity capable of displacing the second portion in the adjustment direction through elastic deformation. The lower feed mechanism includes an adjustment component that displaces the second part in the adjustment direction.

3. The sewing machine according to claim 2, wherein, The adjustment component is mounted on the feed gear table in a manner that abuts against the second part, and the feed screw is provided to move forward and backward in the adjustment direction.

4. The sewing machine according to any one of claims 1 to 3, wherein, The feed tooth has: a fixing portion fixed to the feed tooth platform; a wall portion extending upward from the fixing portion; and an upper surface portion disposed at the upper end of the wall portion and in contact with the object to be sewn. The bearing surface can be positioned between a position close to the needle path compared to the side of the wall portion on the side of the needle path and a position far away from the needle path compared to the side of the wall portion.

5. The sewing machine according to any one of claims 1 to 3, wherein, The vessel has a needle receiving part. The bearing surface of the bearing component is opposite to the needle bearing portion of the vessel in the adjustment direction.

6. The sewing machine according to any one of claims 1 to 3, wherein, It also has an upper feed section that transports the sewing object, supported by the needle plate, from above. This sewing machine is an integrated feed sewing machine that causes the feed teeth, the upper feed section, and the needle bar of the lower feed mechanism to move along a feed trajectory that is linked to each other.

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