JP3885782B2 - Embroidery sewing machine presser mechanism - Google Patents

Description

  More particularly, the present invention relates to a presser foot mechanism for an embroidery sewing machine that can move a presser foot up and down with a small driving force.

  Conventionally, various presser mechanisms for an embroidery sewing machine have been proposed in which, when the work cloth is moved by the embroidery frame, the presser foot can be swung or lifted and released upward. For example, in Patent Document 1, a presser foot support member fixed to a presser bar, a first swing lever pivotally attached to a support shaft disposed on the presser foot support member, and a presser foot that is externally fitted to the support shaft. A coil spring that is a winding spring that elastically biases the first swing lever in a direction in which the foot presses the work cloth and rotates around the support shaft, and an embroidery formed integrally with the first swing lever A fabric presser mechanism for an embroidery sewing machine having a presser foot is described.

In this presser foot mechanism, when the needle bar is driven upward, the mounting shaft screwed to the needle bar comes into contact with the lever portion of the first swing lever, and the first swing member is supported together with the presser foot. It is swung upward around the axis. On the other hand, when the needle bar is driven downward, it is elastically biased in the rotational direction about the support shaft by the coil spring, and the first swing member swings downward around the support shaft together with the presser foot.
Japanese Patent No. 3211336 (page 3-4, Fig. 2-4)

  However, in the cloth presser mechanism of Patent Document 1, the urging force of the coil spring acts in the rotation direction of the vertical surface around the support shaft, and only the force in the vertically downward direction of the urging force is applied to the work cloth as the pressing force. Therefore, in order for the work cloth to have a desired pressing force, there arises a problem that a coil spring having a considerably large spring force must be applied to the pressing force.

  On the other hand, when the presser foot is swung upward, the first rocking lever is rotated by the driving force of the needle bar. However, the presser foot and the first rocking lever are integrally formed, and the support shaft The distance from the presser foot to the presser foot is substantially the same as the distance from the support shaft to the position at which the needle bar mounting shaft of the first swing lever contacts, so that the first swing lever can be driven upward. Since the driving force for acting on the first swing lever via the needle bar is substantially equal to the urging force acting on the presser foot by the coil spring to press the work cloth, the needle bar is driven with a large driving force. Will have to. Although it is possible to lengthen the lever part of the first swing lever and increase the distance between the contact point of the needle bar mounting shaft and the support shaft, the positions of the needle bar and the presser foot in the horizontal plane are substantially the same. In view of this, it is impossible to increase the above-mentioned distance, and if the lever portion is lengthened, the space is required and it cannot be practically used.

  In this presser foot mechanism, since the presser foot is driven to swing and escape upward, the presser foot swing drive amount must be larger than the presser foot lift distance to raise the presser foot to a predetermined height. I must. Since the presser foot is swung around the support shaft, the presser foot moves back and forth with respect to the sewing needle in a plan view, and the needle hole formed in the presser foot must be formed in the front-rear direction. No longer.

  An object of the present invention is to provide a presser foot mechanism for an embroidery sewing machine capable of moving a presser foot up and down with a small driving force.

  According to a first aspect of the present invention, there is provided a presser foot mechanism for an embroidery sewing machine, wherein the embroidery sewing machine presses the work cloth of the embroidery sewing machine, a support member fixed to a lower end portion of the presser bar of the embroidery sewing machine, and a guide support that can be raised and lowered by the support member A presser foot member having a guided shaft and a presser foot fixed to the lower end of the guided shaft, and one end pivotally attached to the support member by a pivot pin. A vertical drive lever that can swing up and down around the pin and receives a driving force from the needle bar drive unit, and elastically biases the presser foot member downward with respect to the support member, and the pivot of the vertical drive lever An elastic member that elastically urges a middle portion between the support pin and the driving force input portion downward is provided.

  According to the presser foot mechanism of the embroidery sewing machine, the presser foot member is elastically biased downward with respect to the support member by the elastic member, and the work cloth is pressed by the presser foot. On the other hand, when the needle bar is raised and the driving force input part of the vertical drive lever receives the upward driving force from the needle bar drive part, the vertical drive lever is driven to swing upward about the pivot pin. The elastic member is pressed upward in the middle of the vertical drive lever between the pivot pin and the driving force input portion, and the presser foot member is raised vertically upward. Next, when the needle bar is lowered, the presser foot member is elastically urged downward by the elastic member, and the upper and lower drive levers are elastically urged downward in the middle, and the work cloth is pressed by the presser foot. The

  The presser foot mechanism for an embroidery sewing machine according to claim 2 is characterized in that, in the invention according to claim 1, a spring receiving pin that is in contact with the middle part of the vertical drive lever from above is fixed to the middle part of the guided shaft, Is composed of a compression coil spring sheathed on the guided shaft between a spring receiving portion formed on the upper end portion of the support member and a spring receiving pin.

  According to the presser foot mechanism of the embroidery sewing machine, the spring receiving pin fixed to the middle portion of the guided shaft by the compression coil spring mounted on the guided shaft, the spring abutting on the middle portion of the vertical drive lever from above The vertical drive lever is elastically biased downward via the receiving pin.

  The cloth presser mechanism for an embroidery sewing machine according to a third aspect is the invention according to the second aspect, wherein the pivot pin is provided with a winding spring that elastically urges the support member in a direction in which the vertical drive lever contacts the spring receiving pin. It is provided. According to the presser foot mechanism of the embroidery sewing machine, the middle portion of the vertical drive lever is elastically biased by the winding spring and is always in contact with the spring receiving pin.

  A cloth presser mechanism for an embroidery sewing machine according to a fourth aspect is the invention according to the third aspect, wherein the support member is provided with a restricting portion for restricting the downward swing of the vertical drive lever at a predetermined position. According to the presser foot mechanism of the embroidery sewing machine, even if the vertical drive lever is swung downward, the swinging downward is regulated at a predetermined position by the restricting portion.

  According to the first aspect of the present invention, since the elastic member elastically biases the presser member guided and supported by the support member so as to move up and down and presses the work cloth with the presser foot, the elastic member has a small elastic force. Can be applied. Also, the presser foot member and the vertical drive lever are configured separately, and the elastic member is pressed upward in the middle part between the pivot pin and the driving force input portion, and the presser foot is held against the elastic biasing downward of the elastic member. Since the foot member is raised, the driving force for raising the presser foot member can be reduced, for example, by pressing the elastic member at an intermediate position between the pivot pin and the driving force input portion, The driving force for raising the member can be reduced to about half of the biasing force. Since the presser foot is driven up and down, the needle hole formed in the presser foot for inserting the sewing needle can be made smaller.

  According to the second aspect of the present invention, since the compression coil spring for elastically urging the presser foot member or the like is mounted on the guided shaft, the cloth presser mechanism of the embroidery sewing machine can be miniaturized. In addition, the same effects as those of the invention of claim 1 can be obtained.

  According to the third aspect of the present invention, since the middle part of the vertical drive lever is always kept in contact with the spring receiving pin by the winding spring, the damage caused by the collision between the middle part and the spring receiving pin is prevented. Sound can also be prevented. In addition, the same effects as those of the invention of claim 2 can be obtained.

  According to the invention of claim 4, since the downward swing of the vertical drive lever is restricted at a predetermined position, it is possible to prevent a decrease in elastic force due to the extension of the winding spring that drives the vertical drive lever beyond the allowable range. it can.

  It is an object of the present invention to provide a presser foot mechanism for an embroidery sewing machine capable of moving the presser foot up and down with a small driving force. A support member fixed to a lower end portion of a presser bar of the embroidery sewing machine, and a support member for the support member. A presser foot member guided and supported so as to be movable up and down, the presser foot member having a guided shaft and a presser foot fixed to a lower end of the guided shaft, and one end of the presser foot pivoted by a support pin. A vertical drive lever that is worn and swings up and down around the pivot pin and receives a driving force from the needle bar drive unit, and elastically urges the presser foot member downward with respect to the support member, and also drives up and down. This is realized by including an elastic member that elastically urges the middle part between the pivot pin of the lever and the driving force input part downward.

A cloth presser mechanism for pressing a work cloth of an embroidery sewing machine according to an embodiment of the present invention will be described with reference to the drawings. In the following description, the top, bottom, left, and right in FIG. For the sake of simplicity, the needle bar 40 and the presser bar 2 are omitted in the drawings excluding FIG.
As shown in FIGS. 1 to 4, the presser foot mechanism 1 of the embroidery sewing machine M includes a presser bar 2 fixed to the embroidery sewing machine M, a support member 3, a presser foot member 4, a pivot pin 5, A drive lever 6, a spring receiving pin 7, a compression coil spring 8, a winding spring 9, and a stopper 10 are provided.

  The support member 3 is fixed to the lower end portion of the presser bar 2 by a fixing screw 2a. The support member 3 is formed on the left front surface, a fixing portion 15 formed on the left front end portion to which the presser bar 2 is fixed, a spring receiving portion 16 formed on the upper end portion, a guide portion 17 formed on the lower end portion, and the left side surface. A restriction groove 18 for restricting the rotation of the guided shaft 25 via the pivot pin 5, a pair of left and right pivot portions 19, 20 that are formed in the rear half portion and support the pivot pin 5 in an inserted state, A pressing plate portion 21 is formed at the rear end portion over the pivot portions 19 and 20 and pressed by one end of the winding spring 9. The spring receiving portion 16 and the guide portion 17 are formed with guide holes 16a and 17a through which a guided shaft 25 of the presser foot member 4 described later is inserted. The pivot portions 19 and 20 are formed with pivot holes 19a and 20a, and the pivot pins 5 are inserted into the pivot holes 19a and 20a so as to be pivotable.

  The presser foot member 4 is guided and supported by the support member 3 so as to be movable up and down. The presser foot member 4 has a columnar guided shaft 25 and a crank-shaped presser foot 26 fixed to the lower end portion of the guided shaft 25. The upper end portion of the guided shaft 25 is slidably inserted into the guide hole 16a, and similarly, the lower end portion is slidably inserted into the guide hole 17a. As shown in FIG. 1, the guided shaft 25 is formed to have a length such that the lower end protrudes downward from the guide portion 17 by a predetermined length at the lower limit position. It can slide upwards. A pin hole 27 in which the spring receiving pin 7 is inserted and fixed is formed in the center portion of the guided shaft 25 in the left-right direction. The presser foot 26 is formed with a needle hole 28 through which the sewing needle 43 is inserted. The lower end portion of the guided shaft 25 is formed in a D-shaped cross section, and the lower end portion is fitted into a D-shaped hole formed in the presser foot 26, and the presser foot 26 is attached to the lower end portion of the guided shaft 25. Therefore, the presser foot 26 can be prevented from rotating with respect to the guided shaft 25.

  As shown in FIG. 3, the vertical drive lever 6 is formed in a reverse “he” shape in a side view. The rear end portion of the vertical drive lever 6 is pivotally attached to the support member 3 by a pivot pin 5 and is supported so as to be swingable up and down around the pivot pin 5. The front end portion of the vertical drive lever 6 extends obliquely upward to the front, and a drive force input portion 30 that receives a drive force from a drive portion 41 of a needle bar 40 described later is formed. A pressing portion 31 that is pressed from above by the spring receiving pin 7 is formed in the middle portion between the pivot pin 5 of the vertical driving lever 6 and the driving force input portion 30. Since the driving force input portion 30 and the pressing portion 31 are covered with the synthetic resin, the sliding of the driving pin 42 of the driving portion 41 in the driving force input portion 30 and the sliding of the spring receiving pin 7 in the pressing portion 31 are smooth. To be done. A pair of left and right pivot portions 32 and 33 are formed at the rear end portion of the vertical drive lever 6, and the pivot pin 5 is fixed to the pivot holes 32 a and 33 a formed in the respective pivot portions 32 and 33. . The pivot portions 32 and 33 are connected to each other at the rear end portion of the vertical drive lever 6 by a connecting portion 34, and a protrusion 34 a is formed at the upper end portion of the connecting portion 34.

  The spring receiving pin 7 is inserted into a pin hole 27 formed in the guided shaft 25. The left end portion of the spring receiving pin 7 is inserted into the restriction groove 18 to restrict the rotation of the guided shaft 25 and, as shown in FIG. The upward movement is restricted at a predetermined upper limit position. The right end portion of the spring receiving pin 7 is in contact with the pressing portion 31 of the vertical drive lever 6 from above. The compression coil spring 8 is externally mounted on the guided shaft 25 between the spring receiving portion 16 and the spring receiving pin 7. The presser foot member 4 is elastically biased downward with respect to the support member 3 via the spring receiving pin 7 by the compression coil spring 8, and the pressing portion 31 of the vertical drive lever 6 is moved downward via the spring receiving pin 7. It is elastically biased.

  Accordingly, when the vertical drive lever 6 is swung upward by the raising of the needle bar 40, the spring receiving pin 7 is pressed upward by the pressing portion 31, and the guided shaft 25 together with the presser foot 26 against the elastic bias. Is raised. On the other hand, when the needle bar 40 is lowered, the spring receiving pin 7 is elastically biased downward by the compression coil spring 8, so that the guided shaft 25 is lowered together with the presser foot 26, and the vertical drive lever 6 is also lowered. It is swung.

  The winding spring 9 is externally mounted on the pivot pin 5. One end of the winding spring 9 is hooked on a protrusion 34a provided at the rear end portion of the vertical drive lever 6, and the other end of the winding spring 9 is provided to press the front surface of the pressing plate portion 21 backward. Yes. Therefore, the vertical drive lever 6 is elastically biased by the winding spring 9 in a direction in contact with the spring receiving pin 7, and the pressing portion 31 of the vertical driving lever 6 does not separate from the spring receiving pin 7. The winding spring 9 only needs to have a spring force to such an extent that the vertical drive lever 6 does not detach from the spring receiving pin 7. Compared with the spring force of the compression coil spring 8, the spring force of the winding spring 9 is extremely low. Is set to a small value.

  As shown in FIGS. 3 and 5, the lower end portion of the right side surface of the support member 3 is provided with a restriction portion 45 that restricts the downward swinging motion of the vertical drive lever 6 at a predetermined position. When the vertical drive lever 6 is swung downward and the vertical drive lever 6 reaches a predetermined position, the vertical drive lever 6 is brought into contact with the restricting portion 45, and the restricting portion 45 causes the vertical drive lever 6 above the predetermined position. Swaying downward is restricted.

  The stopper 10 is made of synthetic resin and has a cylindrical shape, and is fitted around the guided shaft 25 under the spring receiving pin 7. The stopper 10 regulates the downward movement of the guided shaft 25 at a predetermined lower limit position when the guided shaft 25 descends from above.

  The embroidery sewing machine M is provided with a needle bar 40 that is driven up and down together with the sewing needle 43. A drive unit 41 having a drive pin 42 is provided at the center of the needle bar 40 in the vertical direction. When the needle bar 40 is driven up and down, the drive force input unit 30 is pressed upward by the drive pin 42, and the vertical drive lever 6 is swung upward about the pivot pin 5. Since the sewing machine motor for driving the needle bar 40 and the driving force transmitting means for transmitting the rotational driving force of the sewing machine motor are well-known techniques, description thereof will be omitted.

Next, the operation of the above-described cloth presser mechanism 1 will be described.
As shown in FIGS. 1 to 4, the needle bar 40 is driven upward from the state where the presser foot 26 is positioned at the lower limit position and the work cloth is pressed by the presser foot 26 due to the elastic bias of the compression coil spring 8. Then, the driving force input portion 30 of the vertical drive lever 6 is pressed upward by the drive pin 42, and the vertical drive lever 6 is swung upward about the pivot pin 5. When the vertical drive lever 6 is swung upward, the guided shaft 25 is pressed against the presser foot 26 via the spring receiving pin 7 in contact with the pressing portion 31 against the elastic bias of the compression coil spring 8. At the same time, it is lifted while being guided by guide holes 16a and 17a formed in the support member 3, and when the spring receiving pin 7 comes into contact with the upper end portion of the restricting groove 18, as shown in FIG. The foot 26 is stopped at the upper limit position. As shown in FIG. 5, at this upper limit position, the driving force input portion 30 of the vertical drive lever 6 is held in the vertical direction, so that a load in the vertical downward direction hardly acts on the needle bar 40.

  On the other hand, when the needle bar 40 is driven downward from the above-described state, the guided shaft 25 is pressed against the presser foot via the spring receiving pin 7 biased downward by the compression coil spring 8 as the needle bar 40 is lowered. 26, while being guided by the guide holes 16 a and 17 a, the upper and lower drive lever 6 is driven to swing downward about the pivot pin 5 as the pressing portion 31 is pressed by the spring receiving pin 7. When the lower end of the stopper 10 contacts the guide portion 17, the guided shaft 25 is stopped at its lower limit position, and the vertical drive lever 6 is also stopped from swinging downward, and the work cloth is pressed by the presser foot 26. become. At this time, since the vertical drive lever 6 is biased upward by the winding spring 9, the pressing portion 31 of the vertical drive lever 6 is not detached from the spring receiving pin 7.

Next, the effect of the above-described cloth presser mechanism 1 will be described.
In the presser foot mechanism 1, since the biasing force of the compression coil spring 8 acting on the presser foot 26 acts only downward, a spring having a small spring force can be applied to the compression coil spring 8. Further, the spring receiving pin 7 is pressed upward by the pressing portion 31 formed in the middle portion of the pivot pin 5 and the driving force input portion 30, and the presser foot member 4 resists the elastic bias of the compression coil spring 8. Therefore, the driving force necessary to raise the presser foot 4 can be reduced. That is, the ratio of the driving force for raising the presser foot member 4 and the biasing force of the compression coil spring 8 acting on the spring receiving pin 7 is the distance between the pivot pin 5 and the spring receiving pin 7 and the pivot pin 5. And the driving force input unit 30 are approximately equal to the distance ratio, so that the driving force for raising is approximately half of the biasing force of the compression coil spring 8.

  Since the presser foot 26 is raised and lowered in the vertical direction, the needle hole 28 formed in the presser foot 26 can be reduced, the size of the presser foot 26 can be reduced, and the press of the work cloth is released. Therefore, the amount of movement of the presser foot 26 can be reduced. Since the vertical drive lever 6 is always kept in contact with the spring receiving pin 7 by the winding spring 9, damage due to collision between the vertical drive lever 6 and the winding spring 9 and collision noise due to the collision can be prevented. Since the compression coil spring 8 is mounted on the guided shaft 25, the presser foot mechanism 1 can be reduced in size. Since the restricting portion 45 is provided on the support member 3, even if the vertical drive lever 6 is likely to be driven downward by mistake, the swinging operation can be restricted at a predetermined position by the restricting portion 45. Damage such as a decrease in elastic force due to excessive extension of the spring 9 can be prevented.

Next, a modified example in which the above-described embodiment is partially modified will be described.
In the above-described embodiment, the guided shaft 25 is urged downward by the compression coil spring 8, but the elastic member that urges the guided shaft 25 is not limited to the compression coil spring 8. For example, a winding spring fixed to the support member 3 is provided, one end of this winding spring is connected so as to elastically urge the spring receiving pin 7 downward, and the spring receiving pin 7 is connected by the urging force of the winding spring. Alternatively, the guided shaft 25 may be configured to be biased downward.

  The present invention is not limited to the above-described embodiments, and those skilled in the art can implement the present embodiment by adding various modifications without departing from the spirit of the present invention. The present invention includes those modifications.

It is a front view of the cloth presser mechanism of the embroidery sewing machine which concerns on the Example of this invention. It is a left view of a cloth presser mechanism. It is a right view of a cloth presser mechanism. It is a top view of a cloth presser mechanism. FIG. 4 is a view corresponding to FIG. 3 when the presser foot is at the upper limit position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Material presser mechanism 2 Presser bar 3 Support member 4 Presser foot member 5 Pivoting pin 6 Vertical drive lever 7 Spring receiving pin 8 Compression coil spring 9 Winding spring 16 Spring receiving part 25 Guided shaft 26 Presser foot 30 Driving force input part 31 Press part 40 Needle bar M Embroidery sewing machine

Claims (4)

In the presser foot mechanism that presses the work cloth of the embroidery sewing machine,
A support member fixed to the lower end of the presser bar of the embroidery sewing machine;
A presser foot member guided and supported by the support member so as to be movable up and down, the presser foot member having a guided shaft and a presser foot fixed to the lower end of the guided shaft;
A vertical drive lever, one end of which is pivotally attached to the support member by a pivot pin, which is swingable up and down around the pivot pin and receives a driving force from the drive portion of the needle bar;
An elastic member that elastically urges the presser foot member downward with respect to the support member, and elastically urges a middle portion between the pivot pin and the driving force input portion of the vertical drive lever;
A presser foot mechanism for an embroidery sewing machine characterized by comprising:   A spring receiving pin that contacts the intermediate portion of the vertical drive lever from above is fixed to the intermediate portion of the guided shaft, and the elastic member is located between the spring receiving portion formed at the upper end portion of the support member and the spring receiving pin. 2. The presser foot mechanism for an embroidery sewing machine according to claim 1, comprising a compression coil spring mounted on the guided shaft.   3. A presser foot mechanism for an embroidery sewing machine according to claim 2, wherein said pivot support pin is provided with a winding spring that elastically urges a vertical drive lever with respect to said support member in a direction to abut against said spring receiving pin. .   4. The presser foot mechanism for an embroidery sewing machine according to claim 3, wherein the support member is provided with a restricting portion for restricting the downward swing of the vertical drive lever at a predetermined position.

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