JP2009095503A - Presser foot for sewing machine and sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sewing machine having a simple structure which makes it possible to inhibit increase of the number of parts and cost, to maintain embroidering efficiency and to effectively prevent tips of sewing needles from contacting an upper thread. <P>SOLUTION: A needle bar driving mechanism (5, 8 and 9) for driving the sewing needle (7) can be mounted to a presser foot (11 or 50) of the sewing machine in order to hold a workpiece (A) cooperated with movement of the needle (7). The presser foot (11 or 50) has at least one inclined surface (30 or 53) formed on a lower surface of the presser foot (11 or 50). The upper thread (T) is inserted through a thread inserting hole (7a) of the sewing needle (7) and passed across the workpiece (A). The inclined surface (30 or 53) is arranged so that the upper thread (T) is moved to a position so as not to contact the tip of the sewing needle (7) by moving the upper thread (T) along the inclined surface (30 or 53) when the upper thread (T) contacts the inclined surface (30 or 53) while moving with movement of the workpiece (A). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cloth presser (cloth presser fitting) for a sewing machine and a sewing machine including the cloth presser, and more particularly, to a sewing machine capable of retracting an upper thread applied to a moving path of a sewing needle from the moving path. The present invention relates to a cloth presser and a sewing machine including the cloth presser.

  FIG. 9 shows a sewing head included in a conventional industrial embroidery sewing machine, where 100 is a needle bar that is driven up and down, 101 is a sewing needle fixed to the lower end of the needle bar 100, and T is a threading thread of the sewing needle 101. An upper thread passed through the hole 101a (see FIG. 10), A is an article to be sewn held by a horizontally moving sewing frame, and 102 is a needle plate. In this sewing machine, well-known sewing is performed by the cooperation of a sewing needle 101 that moves up and down together with the needle bar 100 and a hook (not shown) provided below the needle plate 102, and the workpiece A is moved horizontally for each stitch. Any embroidery pattern is sewn. Further, as shown in FIG. 9, in a typical conventional cloth presser (cloth presser fitting) 103, the lower surface 103a for presser foot is flat and the entire flat lower surface 103a is pressed against the cloth. It was.

  In such a sewing machine, as shown in FIG. 9, after a stitch is sewn, the sewing needle A moves to the front side (left side in the figure) of the embroidery sewing machine for the next stitch. The upper thread T extending from the threading hole 101a 101 to the sewing product A is inclined forward and backward as indicated by a two-dot chain line T ′. 10 to 12 show an enlarged view of the tip of the sewing needle 101 and the vicinity thereof. At this time, as shown in FIG. 10, the upper thread T may be located directly below the needle tip of the sewing needle 101. When the sewing needle 101 is lowered in this state, the needle tip of the sewing needle 101 comes into contact with the upper thread T as shown in FIG. When the sewing needle 101 is further lowered, the needle tip of the sewing needle 101 is strongly pressed against the upper thread T as shown in FIG. 12, and the sewing needle 101 may pierce the upper thread T in some cases. Thereby, the upper thread T may be damaged or cut.

  The movement of the sewing object A may be started immediately after the sewing needle 101 has pulled out of the sewing object A. In this case, even when the sewing needle 101 is raised, the needle tip of the sewing needle 101 comes into contact with the upper thread T as shown in FIGS. 11 and 12, and the upper thread T may be damaged or cut.

In order to avoid such a problem, the embroidery sewing machine described in Patent Document 1 includes a thread wiper that pays the upper thread out of the moving path of the sewing needle. Further, in the embroidery sewing machine described in Patent Document 2, when the sewing frame is moved from one needle drop position to the next needle drop position, the needle thread is temporarily moved by moving the sewing frame to the side once. It is comprised so that it may retract | save from the movement path | route of a sewing needle.
Japanese Utility Model Publication No.2-2295 JP 2001-62174 A

  When a thread wiper such as the sewing machine described in Patent Document 1 is provided, the number of parts of the sewing machine increases, the structure becomes complicated, and the cost increases. Further, in the sewing machine that temporarily moves the sewing frame to the side like the sewing machine described in Patent Document 2, time is required to move the sewing frame to the side. Therefore, it is necessary to reduce the number of rotations of the sewing machine or to jump the needle bar by one needle (stopping the needle bar up and down by one stitch) with a known jump mechanism, and the embroidery efficiency is reduced accordingly. .

  The present invention has been made in view of the above points, and its purpose is to make the needle tip of the sewing needle contact the upper thread without increasing the number of parts and increasing the cost with a simple structure and without reducing the embroidery efficiency. An object of the present invention is to provide a cloth presser for a sewing machine that can effectively prevent the sewing machine and a sewing machine including the cloth presser.

  In order to solve the above-mentioned problems, a cloth presser for a sewing machine according to the present invention is a cloth presser for a sewing machine that reciprocates up and down in order to press a workpiece in conjunction with the operation of a sewing needle. The upper thread which has at least one inclined surface formed on the lower surface of the presser and is passed through the threading hole of the sewing needle and passed to the sewing product moves along with the movement of the sewing product. The inclined surface is arranged so that when the upper thread comes into contact with the inclined surface, the upper thread is moved along the inclined surface so that the upper thread is released to a position where it does not hit the needle tip of the sewing needle. It is characterized by.

  According to this configuration, the lower surface of the cloth presser is not flat as in the prior art, and at least one inclined surface is formed. When the upper thread coming out of the threading hole of the sewing needle and passing to the sewing product contacts the inclined surface while moving along with the movement of the sewing product, the inclined surface comes into contact with the inclined surface. The upper thread is moved along the inclined surface so that the upper thread is released to a position where it does not hit the needle tip of the sewing needle. Even in such a case, the upper thread can be automatically retracted from the needle tip movement path of the sewing needle. Therefore, the needle tip of the sewing needle does not contact the upper thread, and the upper thread can be effectively prevented from being damaged or cut. Further, it is possible to automatically prevent the needle tip of the sewing needle from contacting the upper thread with a simple configuration in which at least one inclined surface is formed on the lower surface of the cloth presser. Therefore, the structure of the sewing machine is not complicated, and it is not necessary to increase the number of parts and increase the cost. Furthermore, since the upper thread can be automatically retracted from the needle tip movement path of the sewing needle along with the drive control of the sewing product and the presser foot in the normal sewing operation, the contents of the sewing operation control of the sewing machine are the same as the conventional one. It may be the same. Therefore, there is no possibility that the embroidery efficiency of the sewing machine will decrease.

  In the first embodiment, a first presser protrusion is provided on the lower surface of the cloth presser so as to be positioned on the entrance side of the threading hole of the sewing needle. On both sides of the first presser protrusion, each of the first presser protrusions is provided with an inclination so as to rise as it moves away from the first presser protrusion, and the lower surface of the cloth presser is substantially the same height as the first presser protrusion. A second presser protrusion is further provided, and pressing is performed when the first and second presser protrusions hit the sewing product. According to this configuration, when the upper thread moves along one of the pair of inclined surfaces, the upper thread is released to a position where it does not hit the needle tip of the sewing needle.

    In the second embodiment, the lower surface of the cloth presser is provided with a first presser protrusion at a second position shifted from the first position corresponding to the entrance side of the threading hole of the sewing needle. The two inclined surfaces are provided through the first position with an inclination so as to rise as the distance from the first presser protrusion increases. The lower surface of the cloth presser is substantially the same as the first presser protrusion. A second presser protrusion is further provided at the same height, and pressing is performed when the first and second presser protrusions hit the sewing product. According to this configuration, when the upper thread moves along one inclined surface, the upper thread is released to a position where it does not hit the needle tip of the sewing needle.

  As an example, the first and second presser protrusions and the inclined surface are formed around the needle threading hole in a thread relief piece having a needle threading hole, and the thread relief piece is formed on the cloth retainer. Attached to the bottom of the structure.

  According to this configuration, it is possible to simply configure the presser foot according to the present invention by simply attaching the thread relief piece to the lower part of the presser foot having a conventional flat lower surface, and the upper thread is used as the needle of the sewing needle. It becomes possible to automatically evacuate from the destination movement route. Therefore, it is possible to effectively prevent the upper thread from being damaged or cut only by making a slight change to the structure of the conventional sewing machine.

  As another example, the first and second presser protrusions and the inclined surface are formed integrally with the structure at the lower part of the structure of the cloth presser having a needle through hole.

Further, the sewing machine according to the present invention includes a cloth presser for a sewing machine having the above-described configuration, a needle bar that holds the sewing needle at a lower end, the sewing product, and a needle drop position of the sewing needle. A movable sewing frame.

  According to the sewing machine having this configuration, even if the upper thread is applied to the movement path of the needle tip of the sewing needle, the upper thread is automatically moved from the movement path of the needle tip of the sewing needle along the inclined surface formed on the lower surface of the cloth presser. Can be evacuated. Therefore, the needle tip of the sewing needle can be effectively prevented from coming into contact with the upper thread, and the upper thread is not damaged or cut. Further, the structure of the sewing machine is not complicated, and it is not necessary to increase the number of parts and increase the cost. Further, the sewing operation control content of the sewing machine may be the same as the conventional one, and there is no possibility of reducing the embroidery efficiency of the sewing machine.

  According to the cloth presser for a sewing machine and the sewing machine provided with the cloth presser according to the present invention, the simple structure does not lead to an increase in the number of parts and the cost, and the embroidery efficiency is not reduced. It is possible to effectively prevent the upper thread from contacting.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description, the right side or the left side indicates the right side or the left side as viewed from the front of the sewing machine described later.

[First Embodiment]
FIG. 1 is a front view of a sewing head H provided in the embroidery sewing machine according to the first embodiment of the present invention, and FIG. 2 is a side view (partially sectional view) of the sewing head H. The sewing head H of the present embodiment is a multi-needle type sewing head used for an industrial embroidery sewing machine or the like. The sewing head H includes an arm 1 fixed to a sewing machine frame M, and a needle bar case 2 supported in a state in which the arm 1 can slide in the lateral direction. A sewing machine main shaft 4 is provided in the arm 1 so as to penetrate in the lateral direction. The sewing machine main shaft 4 is rotationally driven by a sewing machine driving motor (not shown). A needle plate 3 is provided below the sewing head H, and a well-known hook (not shown) that is rotationally driven is provided below the needle plate 3. The sewing object A positioned on the upper portion of the needle plate 3 is held by a sewing frame (not shown). The sewing frame is driven in the front-rear and left-right directions (XY directions) in the horizontal plane with respect to the needle drop position of the sewing needle 7.

  The needle bar case 2 is provided with a plurality (9 in the figure) of needle bars 5 that can move up and down, and a sewing needle 7 is fixed to the lower end of each needle bar 5 via a needle holder 6. is there. A needle bar holder 8 is fixed to a substantially middle portion of the needle bar 5, and an engagement pin 8 a is formed on the back side of the needle bar holder 8. On the other hand, the arm 1 is provided with a needle bar driving member 9 that moves up and down by the rotation of the sewing machine main shaft 4. The needle bar drive member 9 is formed with an engagement recess 9a that engages with the engagement pin 8a of the selected needle bar 5. By sliding the needle bar case 2 to a position for selecting an arbitrary needle bar 5, the engagement pin 8 a of the needle bar 5 is engaged with the engagement recess 9 a of the needle bar drive member 9. As a result, the selected needle bar 5 moves up and down by the needle bar drive member 9.

  On the outer periphery of the needle bar 5, a cloth presser hug 10 is provided so as to be movable up and down relatively with respect to the needle bar 5, and an engagement pin 10 a is formed on the back side of the cloth presser hug 10. A cloth presser member 11 which is an embodiment of the cloth presser according to the present invention is fixed to the front surface of the presser foot holding body 10. The presser foot member 11 is formed in a long and narrow plate shape extending downward from the presser foot hug 10, and a substantially intermediate portion in the vertical direction is bent into a horizontal contact portion 11a. Details of the presser member 11 will be described later.

  A coil spring 12 that biases the cloth presser member 11 downward is provided between the needle bar holder 8 and the cloth presser holder 10 on the outer periphery of the needle bar 5. Due to the urging force of the coil spring 12, the contact portion 11 a of the presser member 11 is regulated to be pressed against the needle clamp 6 via the cushion 13. In this state, the presser foot 11 and the needle bar 5 are integrally driven up and down while the contact portion 11a is pressed against the needle holder 6.

  The arm 1 is provided with a support member 14 that moves up and down by the rotation of the sewing machine main shaft 4. As will be described later, the support member 14 supports the engagement pin 10 a of the presser foot holding body 10 that moves up and down together with the needle bar 5.

  The top dead center of the needle bar 5 is a position where the stopper 16 fixed above the needle bar holder 8 is received by the lower surface of the horizontal frame 2 a via the cushion 17. A needle bar holding spring 15 for biasing the needle bar 5 upward is provided between the upper end of the needle bar 5 on the outer periphery of the needle bar 5 and the upper surface of the horizontal frame 2a. The needle bar 5 is held at the top dead center position by the urging force of the needle bar holding spring 15 while not being driven by the needle bar driving member 9.

  Each balance 19 corresponding to each needle bar 5 is supported on the balance shaft 18 supported by the needle bar case 2 in a swingable manner. The arm 1 is provided with a balance drive lever 20 that is swung by the rotation of the sewing machine main shaft 4, and the balance drive lever 20 is engaged with a balance 19 corresponding to the selected needle bar 5. . Accordingly, the balance 19 corresponding to the needle bar 5 selected by the swing of the balance drive lever 20 is swung.

  The cloth presser member (cloth presser) 11 will be described in detail. FIG. 3 is a perspective view showing the cloth presser member 11. The presser foot member 11 is composed of a base member (upper structure) 21 fixed to the presser foot hug 10 and a presser foot body (lower structure) 22 connected to the lower end of the base member 21. The base member 21 is formed in an elongated thin plate shape extending vertically, and a fixing portion 21a formed of a through-hole through which a screw for fixing the base member 21 to the cloth holding body 10 is formed at an upper end portion thereof. Has been. The fixed portion 21a is formed as an elongated slot that extends vertically. Thereby, the fixed position of the presser foot member 11 with respect to the presser foot hug 10 can be adjusted up and down. In addition, an insertion portion 11 b made of a through hole through which the needle bar 5 is inserted is formed in the contact portion 11 a provided in the upper and lower intermediate portions of the base member 21. A protruding pin 24 is formed in the vicinity of the lower end portion of the base member 21, and a screw hole (not shown) for fixing the screw 23 is provided below the pin 24.

  The cloth presser body 22 is formed in an elongated thin plate shape extending in the vertical direction, and an engagement hole 25 formed of a through hole is formed at the upper end portion. The engaging hole 25 has a width dimension so that the pin 24 of the base member 21 is fitted in a substantially tight state. Further, a stepped hole 26 into which the head of the screw 23 is fitted is formed below the engagement hole 25. The engagement hole 25 and the stepped hole 26 are formed as long holes that are long in the vertical direction. Thereby, the fixing position of the presser foot 22 to the base member 21 by the screw 23 can be adjusted up and down.

  On the other hand, the lower end portion of the presser foot 22 is bent at a substantially right angle and is formed in a horizontal plane. In the presser foot member 11 according to the present embodiment, a thread release piece 28 is attached to the lower surface of the lower end portion of the presser foot body (lower structure) 22, and the shape and structure of the thread release piece 28 are formed. It has characteristics. The upper end of the thread relief piece 28 is fitted into a through hole provided at the lower end portion of the presser foot 22 (see FIG. 4). As shown in FIGS. 3 to 6, the thread relief piece 28 has a substantially cylindrical shape having an elliptical needle passage hole 27 (see FIG. 6B) for passing the sewing needle 7 in the center, and is located at the front center. A front presser protrusion (first presser protrusion) 29 that protrudes in a substantially V shape is formed on the lower surface of the front center along the major axis direction of the needle passage hole 27, and is also rearward along the major axis direction. A rear presser protrusion (second presser protrusion) 31 that protrudes downward at the same height as the front presser protrusion 29 is formed on the lower surface of the center (opposite side of the front presser protrusion 29). The sewing object A is pressed against the needle plate 3 by the front presser protrusion 29 and the rear presser protrusion 31. A pair of symmetrically inclined surfaces (yarn retracting portions) 30 that are inclined upward as they move away from the front presser protrusion 29 on the left and right sides and rearward on both sides of the front presser protrusion 29 at the cylindrical lower end of the thread relief piece 28. Is formed. That is, the front presser protrusion 29 is a presser protrusion and is the starting end of each inclined surface 30. The slanted surface (yarn retracting portion) 30 provides a yarn escape function. That is, the front presser protrusion 29 (that is, the start end of the inclined surface 30) while the upper thread T coming out of the threading hole 7a of the sewing needle 7 and being transferred to the sewing product A moves along with the movement of the sewing product A. When the upper thread T is moved along the inclined surface 30, the inclined surface 30 is arranged so that the upper thread T is released to a position where it does not hit the needle tip of the sewing needle 7. Has been.

  The arrangement of the front presser protrusion (first presser protrusion) 29 on the thread release piece 28 is preferably determined in consideration of the arrangement of the threading hole 7a of the sewing needle 7. The upper thread T just hits the needle tip of the sewing needle 7 (which may cause damage to the upper thread T) along the axis of the threading hole 7a of the sewing needle 7 (including a slight slant) ), When the workpiece is moved from the exit side of the threading hole 7a toward the entrance side. That is, in such a case, the upper thread T that has come out from the exit side of the threading hole 7a is moved toward the entrance side, so that it comes into contact with the needle tip of the sewing needle 7 and may be damaged. Therefore, in such a case, the inclined surface 30 is provided so that the upper thread T is released along the inclined surface 30 of the yarn escape piece 28. Therefore, in the first embodiment, the front presser protrusion (first presser protrusion) 29 in the thread escape piece 28 is provided so as to be positioned on the inlet side of the threading hole 7a of the sewing needle 7, and inclined on both sides thereof. A surface 30 is provided. As a result, when the upper thread T coming out from the exit side of the threading hole 7a is to be moved toward the entrance side, either the left or right inclined surface 30 at the position of the front presser protrusion (first presser protrusion) 29 is provided. Will be missed along. Normally, the sewing needle 7 is fixed so that the entrance of the threading hole 7a faces the front of the sewing machine so that the threading can be easily performed, so that the sewing needle 7 is provided on the entrance side of the threading hole 7a of the sewing needle 7. The front presser protrusion (first presser protrusion) 29 is positioned on the front side of the sewing machine.

  A sewing operation in the sewing head H having the above-described configuration will be described. First, an arbitrary needle bar 5 is selected by sliding the needle bar case 2 with respect to the arm 1. As a result, the engagement pin 8a of the needle bar holder 8 corresponding to the selected needle bar 5 engages with the engagement recess 9a of the needle bar drive member 9, and the balance 19 corresponding to the needle bar 5 is driven by the balance. Engage with the lever 20. When the sewing machine main shaft 4 is rotated in this state, the selected needle bar 5 reciprocates up and down and the balance 19 corresponding to the needle bar 5 swings up and down.

  At this time, when the needle bar 5 starts to descend from the top dead center, the presser member 11 also begins to descend together with the needle bar 5. Further, the support member 14 starts to descend simultaneously with the start of the lowering of the needle bar 5. Here, the lowering speed of the support member 14 is set slightly slower than the lowering speed of the needle bar 5. As a result, the engagement pin 10 a catches up with the support member 14 at a certain time and is received by the support member 14. Thereafter, in a state where the engaging pin 10a is supported by the support member 14, the presser foot member 11 descends at the lowering speed of the support member 14 and reaches the bottom dead center. During this time, since the descending speed of the needle bar 5 is faster than the descending speed of the presser member 11, the needle bar holder 8 approaches the presser holder 10 and the coil spring 12 is compressed. When the presser foot 11 is at the bottom dead center, the sewing product A is pressed against the throat plate 3 by the front presser protrusion 29 and the rear presser protrusion 31 of the thread relief piece 28 provided at the lower end thereof. .

  After the presser foot member 11 reaches the bottom dead center, the needle bar 5 continues to further lower while the coil spring 12 is compressed by the lowering of the needle bar holder 8. As a result, the sewing needle 7 is inserted into the workpiece A to reach the bottom dead center, and thereafter, the sewing needle 7 turns upward and is withdrawn. During this time, the presser foot member 11 remains at the bottom dead center. After the needle bar 5 is pulled out of the workpiece A, the presser member 11 together with the support member 14 starts to rise from the bottom dead center, and at a certain point, the needle holder 6 contacts the contact portion 11a via the cushion 13. Touch. Thereafter, the contact portion 11a is pushed up by the needle holder 6, the cloth presser member 11 is raised together with the needle bar 5, and the sewing needle 7 and the cloth presser member 11 are returned to the state shown in FIG.

  Here, the retracting operation of the upper thread T by the thread release piece 28 will be described. 4 to 6 are views for explaining the structure of the presser foot member 11 and for explaining the operations of the sewing needle 7 and the presser foot member 11. 4 is a side view (partially sectional view) of the sewing needle 7 and the cloth presser member 11, and FIG. 5A is a side view of the lower end of the cloth presser member 11 and the needle tip of the sewing needle 7 (partially sectional view). 5 (b) is a front view thereof, FIG. 6 (a) is a front view of the lower end of the cloth presser member 11 and the needle tip of the sewing needle 7, and FIG. 5 (b) is a plan view thereof. As shown in FIG. 4, it is assumed that after a stitch is sewn, the sewing product A moves to the front side (left side in the drawing) of the sewing machine by moving the sewing frame for the next stitch. As a result, the upper thread T extending from the threading hole 7a of the sewing needle 7 to the workpiece A is inclined in the front-rear direction in a tensioned state as indicated by a two-dot chain line T ′. In this state, the upper thread T may be located directly below the needle tip of the sewing needle 7. FIG. 5 shows an enlarged view of the needle tip portion of the sewing needle 7 in that case. At this time, the upper thread T is located at a position facing the front presser protrusion 29 as shown in FIG. In this state, when the workpiece A further moves to the front side of the sewing machine, the upper thread T comes into contact with the front presser protrusion 29. Thereafter, the upper thread T that is in contact with the front presser protrusion 29 shifts to either the left or right inclined surface 30. As shown in FIG. 6, the upper thread T that has shifted to the inclined surface 30 is released along the inclined surface 30 to the side of the sewing needle 7. As a result, the upper thread T that is located immediately below the needle tip of the sewing needle 7 is retracted from the movement path of the needle tip of the sewing needle 7. Thus, the needle tip of the sewing needle 7 is prevented from coming into contact with the upper thread T.

  Immediately after the sewing needle 7 is withdrawn from the workpiece A, the presser foot member 11 is in a position near the bottom dead center. Accordingly, even when the movement of the sewing product A by the sewing frame is started immediately after the sewing needle 7 is pulled out of the sewing product A, the upper thread that extends from the threading hole 7a of the sewing needle 7 to the sewing product A T abuts on the front presser protrusion 29 of the thread relief piece 28 as the workpiece A moves. As a result, as in the previous case, the upper thread T moves to the left or right inclined surface 30 and rises along the inclined surface 30 so that it is released to the side of the sewing needle 7. Thus, even when the movement of the sewing object A is started immediately after the sewing needle 7 has pulled out of the sewing object A, the upper thread T is removed from the movement path of the needle tip of the sewing needle 7 by the inclined surface 30. Even when the sewing needle 7 is raised, the needle tip of the sewing needle 7 can be prevented from coming into contact with the upper thread T.

  FIG. 6 shows a case where the upper thread T moves from the front presser protrusion 29 to the right inclined surface 30. However, the upper thread T moves from the front presser protrusion 29 to the left or right inclined surface 30. These are determined in accordance with various situations such as the moving direction of the sewing product A at the time of stitching, and may shift to the left inclined surface 30 depending on the situation.

  As described above, according to the presser member 11 provided in the sewing machine of the present embodiment, even if the upper thread T is applied to the movement path of the needle tip of the sewing needle 7 as the workpiece A moves, the upper surface is moved upward by the inclined surface 30. The thread T can be retracted from the movement path of the needle tip of the sewing needle 7. Accordingly, the needle tip of the sewing needle 7 can be effectively prevented from coming into contact with the upper thread T, and the upper thread T is not damaged or cut. In addition, according to the sewing machine of the present embodiment, the needle tip and the upper thread of the sewing needle 7 can be obtained simply by providing the presser foot 11 with the inclined surface 30 (attaching the thread relief piece 28 having the inclined surface 30 to the presser member 11). Contact with T can be effectively prevented. Therefore, the structure of the sewing machine is not complicated, and it is not necessary to increase the number of parts and increase the cost. Further, according to the sewing machine of the present embodiment, the upper thread T is moved from the movement path of the needle tip of the sewing needle 7 by the inclined surface 30 provided on the cloth presser member 11 along with the movement of the sewing product A in the normal sewing operation. Since it can be retracted, the sewing operation of the sewing machine may be the same as the conventional one. Therefore, there is no need to reduce the number of rotations of the sewing machine or to jump the needle bar by one needle, and there is no possibility that the embroidery efficiency of the sewing machine will decrease.

[Second Embodiment]
Next, an embroidery sewing machine using the cloth presser according to the second embodiment of the present invention will be described. In the drawings and the description thereof according to the second embodiment, parts common to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In addition, matters other than those described below are the same as those in the first embodiment. FIG. 7 shows a side view (partially sectional view) of the sewing head HH provided in the embroidery sewing machine of the second embodiment. The sewing head HH of the present embodiment is slightly different from the sewing head H of the first embodiment in the components and the operation mechanism. That is, the presser foot member 50 provided in the sewing head HH is different from the presser foot member 11 provided in the sewing head H, which is composed of two parts, the base member 21 and the presser foot body 22, as one part. Is formed. Further, the sewing machine head HH is not provided with the cloth presser hug 10, and the upper end of the cloth presser member 50 is directly attached to the outer periphery of the needle bar 5. Accordingly, the engagement pin 10a and the support member 14 that supports the engagement pin 10a provided on the fabric retainer 10 are also omitted.

  The presser foot member 50, which is a presser foot according to the second embodiment of the present invention, is formed in an elongated flat plate shape that extends up and down as a whole, and is intermediate between a horizontal upper contact portion 50a provided at the upper end portion. It has a horizontal intermediate contact portion 50b provided in the portion. In the upper contact portion 50a and the intermediate contact portion 50b, an insertion portion (not shown) including a through hole through which the needle bar 5 passes is formed. A coil spring 12 is provided between the needle bar holder 8 and the upper contact portion 50a to urge the presser member 50 downward. The presser foot 50 is lowered together with the needle bar 5 by the bias of the coil spring 12 as the needle bar holder 8 is lowered. The lowering of the presser foot 50 stops at a position where the lower surface of the upper contact portion 50a contacts the cushion 51 on the horizontal frame 2b provided at the lower portion of the needle bar case 2. The position is the bottom dead center of the presser member 50.

  After the presser foot 50 reaches the bottom dead center, the needle bar 5 continues to descend while the coil spring 12 is compressed by the lowering of the needle bar holder 8. As a result, the sewing needle 7 is inserted into the workpiece A to reach the bottom dead center, and thereafter, the sewing needle 7 turns upward and is withdrawn. During this time, the presser foot member 50 remains at the bottom dead center. After the needle bar 5 is withdrawn from the sewing product A, the needle holder 6 comes into contact with the intermediate contact portion 50b through the cushion 13. Thereafter, the intermediate abutment portion 50 b is pushed up by the needle holder 6, and the presser foot member 50 is raised together with the needle bar 5.

  The presser foot member 50 of the present embodiment includes a thread release piece 52 having a shape different from that of the thread release piece 28 provided in the presser foot member 11 of the first embodiment. That is, the yarn escape piece 52 is attached to the lower part of the structure of the presser foot member 50. FIG. 8 is an enlarged front view of the sewing needle 7 and the cloth presser member 50. The front presser protrusion (first presser protrusion) 54 of the thread escape piece 52 is a position biased to the right when viewed from the front (relative to the front center position (first position) along the major axis direction of the needle passage hole 27). It is formed at (second position). That is, in the second embodiment, the front presser protrusion (first presser protrusion) 54 of the thread escape piece 52 is shifted from the first position corresponding to the inlet side of the threading hole 7a of the sewing needle 7 to the second position. Is provided. An inclined surface (yarn retracting portion) 53 continuous from the front presser protrusion 54 is provided only on the left side of the front presser protrusion 54, and upwards as it rotates from the front presser protrusion 54 to the left (clockwise). It is formed to be inclined. That is, the inclined surface 53 is provided through the first position (front center) with an inclination that rises as the distance from the front pressing protrusion (first pressing protrusion) 54 increases. On the other hand, such an inclined surface (yarn retracting portion) is not provided on the right side of the front presser protrusion 54. As described above, one sloping surface (yarn retracting portion) 53 is formed on the yarn escape piece 52 of the second embodiment.

  According to the thread relief piece 52 of the second embodiment, the upper presser protrusion 54 is formed at a position biased to the right side when viewed from the front, so that the upper thread T is applied to the movement path of the needle tip of the sewing needle 7. Sometimes, the upper thread T first comes into contact with the middle of the inclined surface 53 instead of the front presser protrusion 54 (that is, the starting end of the inclined surface 53), and then the upper thread T is moved along with the movement of the sewing product A. It escapes to the left side of the sewing needle 7 along the inclined surface 53 (as the tension increases, the needle thread T moves upward along the inclined surface so as to release the tension of the upper thread T), and deviates from the movement path of the needle tip of the sewing needle 7. Therefore, also in the present embodiment, it is possible to prevent the needle tip of the sewing needle 7 from coming into contact with the upper thread T when the sewing needle 7 is raised or lowered.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. For example, in the first embodiment, the case where the presser foot member 11 is configured by the base member 21 and the presser foot body 22 which are separate parts is shown, but the base member 21 and the presser foot body 22 of the presser foot member 11 are shown. It is also possible to integrally form with one component.

  Further, if the thread release piece (thread retracting portion) has a shape that can retract the upper thread T from the movement path of the needle tip of the sewing needle 7, it is like the inclined surfaces 30 and 53 shown in the above embodiment. In addition, the inclined surface is not limited to a linear shape, and may be an inclined surface having a curved surface shape such as a spherical shape or a circular arc shape. Further, if the thread relief pieces 28 and 52 have the inclined surfaces 30 and 53 and the presser protrusions (the front presser protrusions 29 and 54) as described above, the specific shapes of the other parts are the same as those in the above embodiment. It is not limited to what is shown.

  In the above-described embodiment, the case where the yarn relief pieces 28 and 52 having the inclined surfaces 30 and 53 are attached to the presser members 11 and 50 has been described. However, the yarn release piece is formed integrally with the structure of the presser member. It may be what you did.

  In the above embodiment, an example in which the present invention is applied to two different types of sewing heads H and HH has been described. However, the specific configuration of the sewing head to which the present invention is applied is not limited to that shown in the above embodiment. It is not limited. In the above embodiment, an example in which the present invention is applied to a multi-needle embroidery sewing machine has been described. However, it goes without saying that the present invention can also be applied to other sewing machines other than a multi-needle embroidery sewing machine.

It is a front view of a sewing machine head of an embroidery sewing machine using a cloth presser concerning a 1st embodiment of the present invention. It is a side view (partial sectional view) of a sewing machine head. It is a perspective view which shows the cloth presser which concerns on 1st Embodiment of this invention. It is a figure for demonstrating the structure and operation | movement of a cloth presser. It is the elements on larger scale of the lower end of a cloth presser and the needlepoint of a sewing needle, (a) is a side (partial section) figure, and (b) is a front view. It is the elements on larger scale of the lower end of a cloth presser, and the needlepoint of a sewing needle, (a) is a front view, (b) is a top view. It is a side view (partial cross section) of a sewing head of an embroidery sewing machine that uses a cloth presser according to a second embodiment of the present invention. It is an enlarged front view of the fabric retainer which concerns on 2nd Embodiment of this invention, and the sewing needle relevant to it. It is the elements on larger scale of the cloth presser in a conventional embroidery sewing machine, and a sewing needle. It is a figure for demonstrating the motion of the sewing needle and upper thread in the conventional embroidery sewing machine. It is a figure for demonstrating the motion of the sewing needle and upper thread in the conventional embroidery sewing machine. It is a figure for demonstrating the motion of the sewing needle and upper thread in the conventional embroidery sewing machine.

Explanation of symbols

1 Arm 2 Needle bar case 3 Needle plate 4 Sewing spindle 5 Needle bar 6 Needle holder 7 Sewing needle 8 Needle bar holder 9 Needle bar drive member 10 Work clamp holder 11 Work clamp member (cloth presser)
12 Coil spring 14 Support member 15 Needle bar holding spring 18 Balance shaft 19 Balance 20 Balance drive lever 21 Base member 22 Work clamp (lower structure)
27 Needle threading hole 28 Thread escape piece 29 Front presser protrusion (first presser protrusion)
30 Inclined surface (thread retracting part)
31 Rear presser protrusion (second presser protrusion)
50 Work clamp member (cloth presser)
52 Yarn Relief Piece 53 Inclined Surface (Thread Retraction Part)
54 Front presser protrusion (first presser protrusion)
55 Rear presser protrusion (second presser protrusion)
A Sewing product H Sewing head HH Sewing head T Upper thread

Claims (8)

A cloth presser for a sewing machine that reciprocates up and down in order to press the workpiece in conjunction with the operation of the sewing needle,
Comprising at least one inclined surface formed on the lower surface of the cloth presser;
When the upper thread coming out of the threading hole of the sewing needle and passing to the sewing product contacts the inclined surface while moving along with the movement of the sewing object, the upper thread contacts the inclined surface. A cloth presser for a sewing machine, characterized in that the inclined surface is arranged so that the upper thread is released to a position where it does not hit the needle tip of the sewing needle by being moved along. A first presser protrusion is provided on the lower surface of the cloth presser so as to be positioned on the entrance side of the threading hole of the sewing needle,
The pair of inclined surfaces are respectively provided on both sides of the first presser protrusion with an inclination so as to rise as the distance from the first presser protrusion increases.
On the lower surface of the cloth presser, a second presser protrusion is further provided at substantially the same height as the first presser protrusion,
Pressing is performed by the first and second presser protrusions coming into contact with the workpiece.
The cloth presser for a sewing machine according to claim 1. The first and second presser protrusions and the pair of inclined surfaces are formed around the needle threading hole in a thread relief piece having a needle threading hole,
The thread relief piece is attached to the lower part of the structure of the presser foot;
The presser foot for a sewing machine according to claim 2. The first and second presser protrusions and the pair of inclined surfaces are integrally formed with the structure at a lower part of the structure of the cloth presser having a needle-passing hole.
The presser foot for a sewing machine according to claim 2. A first presser protrusion is provided on the lower surface of the cloth presser at a second position shifted from the first position corresponding to the entrance side of the threading hole of the sewing needle,
One of the inclined surfaces is provided through the first position with an inclination such that the inclined surface rises away from the first presser protrusion;
On the lower surface of the cloth presser, a second presser protrusion is further provided at substantially the same height as the first presser protrusion,
Pressing is performed by the first and second presser protrusions coming into contact with the workpiece.
The cloth presser for a sewing machine according to claim 1. The first and second presser protrusions and the inclined surface are formed around the needle threading hole in a thread relief piece having a needle threading hole,
The thread relief piece is attached to the lower part of the structure of the presser foot;
The cloth presser for a sewing machine according to claim 5. The first and second presser protrusions and the inclined surface are formed integrally with the structure at a lower part of the structure of the cloth presser having a needle-passing hole.
The cloth presser for a sewing machine according to claim 5. A cloth presser for a sewing machine according to any one of claims 1 to 7,
A needle bar holding the sewing needle at the lower end;
A sewing machine that includes a sewing frame that holds the workpiece and is movable with respect to a needle drop position of the sewing needle.

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