JP2008104718A - Sewing machine feed mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate the switch of the moving track of feed dog between oval and boxy profiles. <P>SOLUTION: The sewing machine 1 is provided with an upper feed foot 14 which feeds a sewing material in contact from above, a vertical feed mechanism which works the upper feed foot 14 to make a vertical feeding action, a horizontal feed mechanism which has a circular eccentric cam 61 to work the upper feed foot 14 to make a vertical oscillation and a triangular cam 62 fixed coaxially on the eccentric cam 61, first and second feed rods 49a and 49b which are driven with the eccentric cam 61 or the triangular cam 62 as a driver to make the horizontal feed mechanism operate a reciprocal oscillation and a switching means which enables the use of the cams 61 and 62 being selectively switched. Switching of the eccentric cam 61 for making the moving track of a lower feed dog 44 oval over to the triangular cam 62 for making the moving track of the lower feed dog 44 boxy in profile enables one unit of sewing machine to selectively switch the two types of moving track of oval feed and boxy feed. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a sewing machine feed mechanism, and more particularly to a sewing machine feed mechanism that feeds a workpiece by combining a horizontal feed operation and a vertical feed operation.

Conventionally, an upper feed leg that feeds the cloth to be sewn from above, a horizontal feed mechanism that imparts a horizontal feed operation to the upper feed leg, and a vertical feed that imparts a vertical feed action to the upper feed leg A sewing machine feed mechanism is known in which the movement trajectory of the upper feed leg draws an oval elliptical trajectory by synthesizing a feed operation in the horizontal direction and the vertical direction (see, for example, Patent Document 1). ).
The conventional sewing machine feed mechanism transmits so-called elliptical feed by transmitting a horizontal or vertical reciprocating swing motion to an upper feed leg by an eccentric cam fixed to a lower shaft driven by a sewing machine motor (not shown). It is possible. By this elliptical feeding, it is possible to realize a feeding mechanism suitable for high speed operation with less vibration and noise.
On the other hand, there is also known a sewing machine feed mechanism that performs so-called box feed in which the above-mentioned eccentric cam is a triangular cam and the upper feed leg draws a substantially rectangular movement locus. According to this box feeding, a feeding operation suitable for overcoming the step portion can be performed, and the feeding amount can be made substantially constant regardless of the thickness of the cloth.
JP-A-4-164485

By the way, in general, the upper feed leg can escape upward in accordance with the thickness of the cloth, and the cloth is fed in contact with the upper surface regardless of the thickness of the cloth. For this reason, when the cloth is fed by the elliptical feed, the horizontal feed amount by the upper feed leg varies depending on the thickness of the cloth. Further, when sewing a thick material to be sewn, it is preferable to switch to box feeding which is advantageous for overcoming a stepped portion. On the other hand, a thin cloth may be sewn using a sewing machine having a triangular cam. In such a case, it is preferable to use an eccentric cam suitable for high-speed rotation in order to increase production efficiency.
However, the conventional sewing machine feed mechanism is not easy to replace the eccentric cam with the triangular cam, or to replace the triangular cam with the eccentric cam, and has different cams (eccentric cam or triangular cam) mounted separately. There are problems that using different sewing machines is expensive and inconvenient.

  An object of the present invention is to make it possible to easily switch the movement trajectory of the upper feed leg between an elliptical type and a box type.

  In order to solve the above-mentioned problems, the invention according to claim 1 is directed to an upper feed leg that feeds a sewing product in contact with the upper side, a vertical feed mechanism that applies a vertical feed operation to the upper feed leg, and a rotary shaft. A circular eccentric cam that is fixed and imparts a reciprocating swinging motion in the horizontal direction to the upper feed leg; and a triangular cam fixed coaxially with the eccentric cam; and a horizontal feed operation on the upper feed leg A horizontal feed mechanism that imparts a reciprocating motion to the horizontal feed mechanism by being driven by the eccentric cam or the triangular cam as an original node, and selectively switching between the eccentric cam and the triangular cam The sewing machine feed mechanism is characterized by comprising a switching means which can be used in the first place.

  The invention according to claim 2 is the invention according to claim 1, wherein the transmission member includes a first rod member that engages with the eccentric cam, and a second rod member that engages with the triangular cam. The switching means moves the trajectory of the upper feed foot by switching the transmission state of the feed operation from either one of the first rod member or the second rod member to the connected state and the other to the released state. Is provided so as to be switchable.

  According to a third aspect of the present invention, in the first aspect of the invention, the eccentric cam and the triangular cam are provided adjacent to each other in the thrust direction and can be moved and positioned in the thrust direction with respect to the rotation shaft. The means is capable of switching the movement trajectory of the upper feed leg by moving the thrust position of the eccentric cam and the triangular cam with respect to the rotating shaft and switching the cam engaged with the transmission member to the eccentric cam or the triangular cam. It is provided.

  According to a fourth aspect of the present invention, in the first aspect of the invention, the eccentric cam and the triangular cam are adjacent to each other in the thrust direction, and the transmission member is a first engaging portion that engages with the eccentric cam; A second engagement portion that engages with the triangular cam, and a first engagement avoidance portion that avoids engagement between the eccentric cam and the transmission member when the triangular cam engages with the second engagement portion. And a second engagement avoiding portion for avoiding engagement between the triangular cam and the transmission member when the eccentric cam engages with the first engaging portion. The switching means moves the transmission member to switch to a position where the first engagement portion and the eccentric cam or the second engagement portion and the triangular cam engage with each other. A movement position that is provided so that the movement locus can be switched and is positioned so as to hold each position. Characterized in that it comprises a fit means.

  According to the first aspect of the invention, the switching means can selectively switch between the eccentric cam and the triangular cam fixed on the same axis. As a result, a feed operation in the horizontal direction is applied from one of the cams to the horizontal feed mechanism via the transmission member, and the movement of the feed operation by the upper feed leg is interlocked with the feed operation in the vertical direction by the vertical feed mechanism. The trajectory can be switched between elliptical feeding and box feeding. That is, since it is possible to easily switch between elliptical feeding and box feeding with a single sewing machine, operability and productivity can be improved.

  According to the second aspect of the present invention, the same effect as that of the first aspect of the invention can be obtained, and in particular, from one rod member in which the transmission state of the feeding operation to the upper feed leg is in the coupled state. Only the upper feed leg is provided with a feed operation, and the feed operation is not given to the upper feed leg from the other rod member whose transmission state to the upper feed leg is released. Therefore, by connecting the feeding operation from the first rod member to the upper feeding foot, the feeding operation of the elliptical feeding by the eccentric cam can be given to the upper feeding foot, and the upper feeding foot from the second rod member can be given. By setting the feed operation to the foot in the connected state, the box feed feed operation by the triangular cam can be applied to the upper feed foot.

  According to the third aspect of the invention, the same effect as that of the first aspect of the invention can be obtained. In particular, the eccentric cam and the triangular cam that are adjacent to each other in the thrust direction on the same axis are moved in the thrust direction. Thus, the cam engaged with the transmission member can be switched to either the eccentric cam or the triangular cam. In other words, the eccentric cam and the triangular cam are moved with respect to the thrust direction of the rotating shaft by the switching means and positioned at a position where either one of the cams engages with the transmission member, thereby feeding the upper feed leg. The operation can be easily switched between elliptical feeding and box feeding.

  According to the invention described in claim 4, the same effect as that of the invention described in claim 1 can be obtained, and in particular, the transmission member is placed in the frame body portion of the transmission member by the moving positioning means provided in the switching means. When the first engagement portion and the eccentric cam are moved to a position where the first engagement portion and the eccentric cam are engaged and the position is held, the triangular cam is disposed in the second engagement avoiding portion, and therefore the triangular cam and the transmission member An elliptical feed operation is applied from the eccentric cam to the upper feed leg without engaging. Further, when the transmission member is moved and held by the moving positioning means to a position where the second engagement portion of the transmission member and the triangular cam are engaged, the eccentric cam is arranged in the first engagement avoiding portion. Therefore, the eccentric cam and the transmission member do not engage with each other, and a box feed feed operation is applied from the triangular cam to the upper feed leg. In other words, the feed operation applied to the upper feed leg can be easily switched between the elliptical feed and the box feed simply by switching the position of the transmission member by the moving positioning means and positioning at the position.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. In the present embodiment, a general feed sewing machine will be described as an example of the feed mechanism of the sewing machine. The total feed sewing machine, for example, synchronizes the needle feed operation with the sewing needle, the upper feed operation with the upper feed foot, and the lower feed operation with the lower feed dog in order to prevent the sewing product from shifting due to the feed operation. Thus, the sewing machine performs feeding while a sewing needle is pierced into a thick sewing product (for example, a skin). Here, in the following description, the direction along the feed direction (arrow F) is the X-axis direction (front-rear direction), the longitudinal direction of the sewing machine arm 8 orthogonal to the X-axis direction is the Y-axis direction (left-right direction), and the X-axis direction. A direction perpendicular to both the Y-axis direction and the Y-axis direction is defined as a Z-axis direction (vertical direction).

(Overall configuration of the embodiment)
FIG. 1 is a mechanism diagram of the general feed sewing machine 1. As shown in FIG. 1, an overall feed sewing machine 1 (hereinafter simply referred to as a sewing machine 1) includes a sewing machine frame 2, an upper shaft 9 as a main shaft rotatably supported in the sewing machine frame 2, and the upper shaft 9. A sewing machine motor 60 that is a rotational drive source for applying a rotational force to the sewing machine, a presser mechanism 20 that presses the workpiece toward the needle plate from above by a presser foot 20 that is supported in the sewing machine frame 2 so as to move up and down, and a sewing machine motor 60. By driving the sewing needle 12 up and down and swinging along the sewing direction F, a needle feed mechanism 90 for feeding the sewing product, an upper feed foot 14 for feeding the sewing product in contact with the upper side, and rotation A circular eccentric cam 61 fixed to the lower shaft 37 as a shaft and imparting a reciprocating swinging motion in the horizontal direction to the upper feed leg 14; and a triangular cam 62 fixed coaxially to the eccentric cam 61; Water on top feed leg 14 Reciprocating to the horizontal feed mechanism by being driven with the eccentric cam 61 or the triangular cam 62 as the original node, a horizontal feed mechanism that gives a feed operation in the direction, a vertical feed mechanism that gives the upper feed leg 14 a vertical feed operation, The first horizontal feed rod 49a and the second horizontal feed rod 49b as transmission members for imparting the swinging operation, the switching means for selectively switching between the eccentric cam 61 and the triangular cam 62, and the upper feed The upper feed mechanism 94 for alternately moving the foot 14 and the presser foot 20 up and down and swinging the upper feed foot 14 to feed an article to be sewn, and the lower feed teeth 44 provided below the needle plate, along the sewing direction F. And a feed amount adjusting mechanism 96 for adjusting the feed amount by the needle feed mechanism, the upper feed mechanism, and the lower feed mechanism per stitch.

(Configuration on the sewing machine arm side)
First, the configuration of the sewing machine arm 2 on the sewing machine arm 2 side will be described. As shown in FIG. 1, inside the sewing machine arm 8, an upper shaft 9 rotatably supported by the sewing machine arm 8 and a parallel arrangement with respect to the upper shaft 9 are rotatably supported. A needle bar swinging shaft 10 is provided. The upper shaft 9 and the needle bar swinging shaft 10 extend along the Y-axis direction perpendicular to the sewing direction F. A sewing motor 60 as a rotational drive source is connected to the upper shaft 9, and the upper shaft 9 rotates as the sewing motor 60 rotates.

(Needle feed mechanism)
FIG. 2 is a side view illustrating a schematic configuration around the needle bar swinging base 11. As shown in FIG. 2, the needle bar rocking base 11 supports a needle bar 13 that holds the sewing needle 12 and an upper feed leg 14 that is in contact with the upper side and feeds the workpiece. One end of the needle bar swing shaft 10 is connected to one end of the needle bar swing base 11 (see FIG. 1). Connected to the other end of the needle bar swing shaft 10 is a needle bar swing bar 59 (described later) that swings at the same cycle as the lower feed dog 44 synchronized with the vertical movement cycle of the sewing needle 12. The needle bar swing shaft 10 is connected to a lower feed mechanism 91 (described later) via a needle bar swing rod 59, so that the needle bar swing shaft 10 can reciprocate in synchronization with the feed operation of the lower feed dog 44. Do.

  When the needle bar swinging base 11 is swung with the rotation of the needle bar swinging shaft 10, the lower ends of the needle bar 13 and the upper feed leg 14 are swung in the sewing direction F. That is, the upper shaft 9, the needle bar swinging rod 59, the needle bar swinging shaft 10 and the needle bar swinging base 11 constitute a needle swinging mechanism for swinging the sewing needle 12 along the sewing direction F. The needle bar 13 is connected to an eccentric cam 15 attached to the upper shaft 9 via a link member 16, and moves up and down in conjunction with the rotation of the upper shaft 9. That is, the upper shaft 9, the eccentric cam 15, and the link member 16 constitute a needle up-and-down movement mechanism that applies a vertical movement to the sewing needle 12. The needle swing mechanism and the needle up-and-down movement mechanism are interlocked with each other by being driven in accordance with the rotation of the upper shaft 9, and the sewing needle 12 is moved by the needle swing mechanism and the needle up-and-down movement mechanism. A needle feed mechanism 90 is configured to feed the workpiece to be sewn in the sewing direction F while penetrating downward.

(Upper feed mechanism)
On the other hand, a substantially triangular bell crank 18 is connected to the upper end of the upper feed leg 14 via a link member 17. Further, a presser foot 20 is connected via a link member 19 to a connection position 18b behind the connection position 18a with the link member 17 in the bell crank 18 (left side as viewed in the direction of the arrow I in FIG. 1). The presser foot 20 is restricted from moving in the sewing direction, and is supported so that it can only move up and down. Further, the lower end portion of the transmission arm 22 is rotatably connected to the upper connection position 18 c of the bell crank 18 via the link member 21. The upper end portion of the transmission arm 22 is fixed to one end portion of the swing shaft 23 that is linked to the upper shaft 9. The other end of the swing shaft 23 is connected to a rotation connecting portion 24 that rotates together with the swing shaft 23. A crank rod 25 connected to the upper shaft 9 is connected to the rotation connecting portion 24 via a link member 26.

Then, the rotation of the upper shaft 9 is transmitted to the swing shaft 23 via the crank rod 25, the link member 26, and the rotation connecting portion 24, and the swing shaft 23 is rotated. When the swing shaft 23 reciprocally rotates in conjunction with the upper shaft 9, the upper coupling position 18 c of the bell crank 18 is swung along the sewing direction F via the transmission arm 22 and the link member 21. When the upper connecting position 18c of the bell crank 18 is swung to the right as viewed in the direction of the arrow I shown in FIG. 1, the bell crank 18 itself rotates clockwise and the upper feed leg 14 is lowered. When the upper feed leg 14 comes into contact with the upper surface of the sewing product by this lowering, the lowering of the upper feed leg 14 is restricted, and the bell crank 18 rotates clockwise as viewed in the direction of the arrow I around the connecting position 18a. To turn. Thereby, the connecting position 18b of the bell crank 18 is raised, and the presser foot 20 is raised.
On the other hand, when the upper coupling position 18c of the bell crank 18 is swung to the left as viewed in the direction of the arrow I shown in FIG. 1, the bell crank 18 itself rotates counterclockwise and the presser foot 20 is lowered. When the presser foot 20 comes into contact with the upper surface of the sewing product by this lowering, the lowering of the presser foot 20 is restricted, and the bell crank 18 rotates counterclockwise as viewed in the direction of the arrow I with the connecting position 18b as the center. Move. As a result, the connecting position 18a of the bell crank 18 is raised, and the upper feed leg 14 is raised.

  That is, the upper feed foot 14 and the presser foot 20 move up and down in opposite phases, that is, alternately with the swing of the link member 21, and the bell crank 18, the link member 21, the transmission arm 22, The moving shaft 23, the rotation connecting portion 24, the crank rod 25, the link member 26, and the like constitute a vertical feed mechanism according to this embodiment that applies a vertical feed operation to the upper feed leg 14. Further, since the needle bar rocking base 11 is swung even when the upper feed leg 14 is moved up and down, the upper feed leg 14 is swung in the sewing direction F while moving up and down. Then, the upper feed leg 14 is vertically moved by the swing shaft 23, the transmission arm 22, the link member 21, the bell crank 18 and the like, and the upper feed leg 14 is swung by the needle bar swing shaft 10 and the needle bar swing base 11 and the like. The upper feed foot 14 and the presser foot 20 are alternately moved up and down by the moving operation, and the upper feed mechanism 94 is configured to swing the upper feed foot 14 and contact the sewing product from above.

(Height adjustment mechanism)
As shown in FIG. 1, a pair of clamping members 27 that clamp the link member 26 are connected to the crank rod 25 so as to be coaxial with the upper end portion of the link member 26. An adjustment block 28 for adjusting the initial position of the crank rod 25 is connected via the clamping member 27. The adjustment block 28 is fixed to one end portion of an adjustment shaft 29 that is provided so as to be rotatable in parallel with the upper shaft 9, and the inclination angle of the adjustment block 28 varies as the adjustment shaft 29 is rotated. A protrusion 30 for adjusting the rotation angle is fixed to the adjustment shaft 29, and a rotatable ball-shaped rotating plate 32 is in contact with the protrusion 31 of the protrusion 30. Since the distance from the rotating shaft to the outer periphery of the rotating plate 32 is different at each location, the protrusion 31 is raised and lowered as the rotating plate 32 rotates. The protrusion 30 is rotated by the elevation of the protrusion 31 and the adjustment shaft 29 is rotated. A manual dial 33 is connected to the rotating plate 32, and the rotating plate 32 is rotated by rotating the dial 33.
As shown in FIG. 1, one end side of an arm member 29 a is fixed to the adjustment shaft 29, and the other end side of the arm member 29 a is disposed at a position where it can contact the rod of the cylinder 51. When the cylinder 51 is lowered, the protrusion 31 fixed to the adjustment shaft 29 comes into contact with the rotary plate 32 connected to the dial 33, and a predetermined amount of gap is provided between the rod of the cylinder 51 and the arm member 29a. It is secured. When the cylinder 51 is raised, the rod of the cylinder 51 contacts the arm member 29a to rotate the adjustment shaft 29 in the clockwise direction, and the protrusion 31 is separated from the rotating plate 32 by a predetermined amount.

  Here, when the cylinder 51 is raised, the adjustment shaft 29 is rotated in the clockwise direction, and the adjustment block 28 is rotated in the clockwise direction. When the adjustment block 28 is rotated in the clockwise direction, the connection point between the clamping member 27 and the crank rod 25 moves. As the crank rod 25 reciprocates, the swing shaft 23 rotates more and the swing angle increases. Thereby, the vertical amount of the upper feed foot 14 and the presser foot 20 is increased, and the top dead center position is also increased. When the cylinder 51 is lowered, the vertical amount of the upper feed foot 14 and the presser foot 20 becomes the vertical amount set by the dial 33. That is, in this embodiment, the height adjustment mechanism is configured by the dial 33, the rotating plate 32, the cylinder 51, the adjustment shaft 29, the adjustment block 28, the clamping member 27, the crank rod 25, and the like. Further, the adjustment of the inclination angle of the adjustment block 28 by the dial 33 can be adjusted in multiple steps within a range smaller than the adjustment amount by the cylinder 51. The dial 33 may be, for example, a lever.

(Configuration on the machine bed side)
Next, the configuration of the sewing machine frame 2 on the machine bed 50 side will be described. As shown in FIGS. 1 and 3, inside the sewing machine bed 50, a lower shaft 37 that is connected to the upper shaft 9 via pulleys 34, 35 and a belt 36, and rotates fully in conjunction with the upper shaft 9, There are provided a vertical feed shaft 38 and a horizontal feed shaft 39 which are arranged in parallel to the lower shaft 37 and are rotatably supported.

(Bottom feed mechanism)
One end of a vertical feed rod 46 extending in the horizontal direction (X-axis direction) of the lower shaft 37 is connected to the lower shaft 37 via an eccentric cam, and the other end of the vertical feed rod 46 is connected. Is pivotably connected to a vertical feed shaft arm 45 projecting from the top of the vertical feed shaft 38. The vertical feed shaft 38 has an extending portion 40 that protrudes in the horizontal direction, and one end of a feed base 42 that supports the lower feed dog 44 rotates through the link member 41. It is connected freely. When the vertical feed rod 46 is swung in the X-axis direction along with the full rotation of the lower shaft 37, the vertical feed shaft 38 reciprocates and the extension arm is moved according to the rotation of the vertical feed shaft 38. A vertical swing is applied to the feed base 42 via the link member 41 and the link member 41.

  Further, the lower shaft 37 is rotatably connected to the lower end of the first horizontal feed rod 49a via a circular eccentric cam 61 fixed to the lower shaft 37. The first horizontal feed rod 49 a (transmission member) functions as the first rod member of the present embodiment that engages with the eccentric cam 61. The upper end of the first horizontal feed rod 49a is rotatably connected to the central portion of a substantially helical bell crank 48a provided along the X-axis direction above the first horizontal feed rod 49a. . One end of the bell crank 48a is rotatably connected to a horizontal feed shaft arm 47a projecting from the top of the horizontal feed shaft 39, and the other end of the bell crank 48a is fed through a square piece 54a. It is slidably connected in the groove 53 of the quantity converter 52a. When the first horizontal feed rod 49a is swung up and down in accordance with the rotation of the lower shaft 37, the bell crank 48a is moved in accordance with the inclination of the groove 53 formed in the feed amount converter 52a (described later). The reciprocating power is applied to the horizontal feed shaft 39 by swinging in the axial direction. Thereby, the horizontal feed is imparted to the lower feed dog 44 supported on the upper part of the feed base 42 via the feed base arm 43 extending upward from the horizontal feed shaft 39.

  The horizontal feed shaft 39 is connected to the lower end of a needle bar swinging rod 59 fixedly connected to the needle bar swinging shaft 10 at the end opposite to the lower feed dog 44 side. The rotational driving force of the feed shaft 39 is transmitted to the needle bar swing shaft 10 through the needle bar swing rod 59. That is, as the lower shaft 37 rotates, the eccentric cam 61, the first horizontal feed rod 49a, the bell crank 48b, the horizontal feed shaft 39, the needle bar swinging shaft 59, the needle bar swinging shaft 10 and the needle bar swinging base 11 are used. A horizontal swinging force is transmitted to the needle bar 13 and the upper feed leg 14 via the needle. The horizontal feed shaft 39 has its reciprocating rotation angle and phase adjusted by a feed amount adjusting mechanism 96 described later. When the reciprocating rotation angle and phase of the horizontal feed shaft 39 are adjusted by the feed amount adjusting mechanism 96, the swing angle amount and phase of the needle bar 13 and the upper feed leg 14 are also adjusted at the same time. The sewing product is fed in the forward direction or the reverse direction with a horizontal movement amount corresponding to the rotation amount, that is, a feed pitch.

Further, a substantially triangular triangular cam 62 is fixed to the lower shaft 37 so as to be coaxially adjacent to the eccentric cam 61, and provided on the outer periphery of the triangular cam 62 at the lower end of the second horizontal feed rod 49b. The substantially U-shaped engaging portion in side view is slidably fitted.
The triangular cam 62 is a kind of positive cam, which is a cam device imparted with a mechanical constraint, and can follow the cam contour curve reliably without borrowing gravity or spring force. It can be done. As shown in FIG. 12, the outer shape of the triangular cam 62 is composed of a circle having a radius r2 centered on the apex OPQ of the regular triangle and a tangent circle having a radius r1 in each circle. Accordingly, the width L of the triangular cam 62 is always constant at r1 + r2. When the triangular cam 62 which is the original node rotates around the point O, the horizontal feed rod 49b as a follower, that is, a cam follower, performs an intermittent reciprocating linear motion in the vertical direction.
The second horizontal feed rod 49 b (transmission member) functions as the second rod member of this embodiment that engages with the triangular cam 62. The upper end of the second horizontal feed rod 49b is rotatably connected to the central portion of a substantially bell-shaped bell crank 48b provided side by side with the bell crank 48a. Similar to the bell crank 48a, one end of the bell crank 48b is rotatably connected to a horizontal feed shaft arm 47b projecting from the top of the horizontal feed shaft 39. The other end of the bell crank 48b is It is slidably connected in a groove 53b of a feed amount converter 52b that is coaxially connected to the feed amount converter 52a via a piece 54b.

When the second horizontal feed rod 49b is swung up and down with the rotation of the lower shaft 37, the bell crank 48b is moved in the X-axis direction according to the inclination of the groove 53b formed in the feed amount conversion body 52b. A reciprocating power is applied to the horizontal feed shaft 39. Accordingly, the lower feed dog 44 is given horizontal swing through the feed base arm 43 and the feed base 42, and the needle bar swing rod 59, needle bar swing shaft 10, and needle bar swing base are provided. 11, a horizontal feed operation is applied to the needle bar 13 and the upper feed leg 14. In other words, in the present embodiment, the above-described members 61, 62, 49 a, 49 b, 48 a, 48 b, 47 a, 47 b, 39, 59, 10, 11 impart a horizontal feed operation to the upper feed leg 14. The horizontal feed mechanism of the embodiment is configured.
Further, the vertical feed shaft 38 and the horizontal feed shaft 39 are interlocked with each other according to the rotation of the lower shaft 37, so that the vertical and horizontal swinging operations are combined and transmitted to the feed dog 44. A lower feed mechanism 91 is configured to move 44 while appearing above and below the needle plate to feed the workpiece.

(Switching means)
Here, when the rotational force is applied to the horizontal feed shaft 39 through the eccentric cam 61, the first horizontal feed rod 49a, and the bell crank 48a by the rotation of the lower shaft 37, the upper feed foot 14 is shown in FIG. Draw an ellipse feed trajectory as shown in On the other hand, when turning force is applied to the horizontal feed shaft 39 through the triangular cam 38b, the second horizontal feed rod 49b, and the bell crank 48b, the upper feed leg 14 is substantially rectangular as shown in FIG. Draw the movement trajectory of the box feed. The first horizontal feed rod 49a or the second horizontal feed rod 49b (feed triangular cam rod) switches the transmission state of the feed operation from either one to the upper feed foot 14 and switches the other to the release state. Thus, it functions as a switching means of the present embodiment for switching the movement trajectory of the upper feed leg 14.

(Feed adjustment mechanism)
As shown in FIGS. 1 and 3, a feed amount conversion body 52 having a groove portion 53 that is rotatably supported by the sewing machine frame 2 and extends in a direction orthogonal to the rotation center line direction inside the sewing machine bed 50. Is provided. One end of a bell crank 48a is slidably connected to the groove 53 of the feed amount converter 52 via a square piece 54 along the direction in which the groove 53 is formed (see FIG. 4).
FIG. 6 is an exploded perspective view showing the relationship between the feed amount converter 52 and the feed adjustment motor 4. As shown in FIG. 6, the feed amount conversion body 52 is connected to the feed adjustment motor 4 via an arm member 56, a link member 57 and a swing shaft 58.
Here, when the feed amount converter 52 rotates, the groove portion 53 also rotates, so that the amount of movement in the horizontal direction of one end of the bell crank 48a changes via the square piece 54. Specifically, the movement amount in the horizontal direction of the bell crank 48a increases if the groove 53 is close to the horizontal, whereas the movement amount in the horizontal direction decreases if the groove 53 is close to the vertical (see FIG. 5). That is, the feed amount conversion body 52 is rotated by driving the feed adjustment motor 4 so that the feed amount (feed pitch) by the lower feed dog 44 can be adjusted.
In the present embodiment, the lower feed mechanism, the upper feed mechanism, and the needle feed mechanism are interlocked with each other, and these mechanisms cooperate to perform total feed. Therefore, the feed amount adjusting mechanism 96 feeds the lower feed mechanism 91. When is adjusted, the needle swing amount and the feed amount of the upper feed leg 14 are simultaneously adjusted via the needle bar swinging rod 59.

(Explanation of operation of general feed sewing machine)
Next, the operation of the general feed sewing machine 1 will be described in detail.
First, when the elliptical feed movement locus is drawn on the upper feed leg 14, one end of one bell crank 48a is connected to the horizontal feed shaft arm 47a, and one end of the other bell crank 48b is connected to the horizontal feed shaft arm 48b. Is released. Thereby, along with the rotation of the lower shaft 37, rotational force is applied to the horizontal feed shaft 39 via the eccentric cam 61, the first horizontal feed rod 49a, and the bell crank 48a, and the upper feed foot 14 draws a movement trajectory of elliptical feed. (See FIG. 7 (a)). Since the feed leg 14 is retracted upward in accordance with the thickness of the sewing product, when the feed leg 14 is fed in the sewing direction F while being in contact with the upper surface of the sewing product, the lower movement locus of the elliptical track is illustrated. It becomes a linear shape as shown in 7 (a). The trajectory L1 is a movement trajectory of the upper feed leg 14 when a thin sewing product is sent, and the trajectory L2 is a movement trajectory of the upper feed leg 14 when a thick sewing product is sent.
On the other hand, when the box feed movement trajectory is drawn on the upper feed leg 14, the connection between one end of the bell crank 48a and the horizontal feed shaft arm 47a is released, and the one end of the bell crank 48b and the horizontal feed shaft arm 48b are connected. State. As a result, rotational force is applied to the horizontal feed shaft 39 via the triangular cam 38b, the second horizontal feed rod 49b, and the bell crank 48b, and the upper feed foot 14 is a substantially square box feed as shown in FIG. 7B. Draw a movement trajectory. The locus L1 is a movement locus of the upper feed leg 14 when a thin sewing product is fed, and the locus L2 is a movement locus of the upper feed leg 14 when a thick workpiece is fed, as in the case of elliptical feeding. .

(First embodiment: effect)
As described above, according to the overall feed sewing machine 1 according to the first embodiment, the feed operation from the first horizontal feed rod 48a to the upper feed leg 14 is set in the connected state, whereby the feed operation of the elliptical feed by the eccentric cam 61 is performed. Can be applied to the upper feed leg 14, and the box feed feed operation by the triangular cam 62 can be performed by connecting the feed operation from the second horizontal feed rod 48b to the upper feed leg 14 in a connected state. 14. In other words, by selectively switching between the eccentric cam 61 and the triangular cam 62 fixed on the same axis, it is possible to easily switch between elliptical feed and box feed with a single sewing machine. Improvement and productivity improvement are achieved.

(Second embodiment)
Next, based on FIG.8 and FIG.9, 2nd embodiment to which this invention is applied is described.
As shown in FIG. 8, the sewing machine 101 according to the second embodiment is provided with an eccentric cam 161 and a triangular cam 162 that are adjacent to each other in the thrust direction and that can be moved and positioned in the thrust direction with respect to the lower shaft 37. The means moves the thrust position of the eccentric cam 161 and the triangular cam 162 with respect to the lower shaft 37, and switches the cam engaged with the horizontal feed rod 149 as a transmission member to the eccentric cam 161 or the triangular cam 162, thereby causing the upper feed leg 14 to move. This is different from the first embodiment in that the movement trajectory is switched.
Specifically, as shown in FIG. 8, a substantially circular eccentric cam 161 and a triangular cam 162 are provided as an integral cam portion 160 adjacent to each other in the thrust direction, and the cam portion 160 is arranged in the Y-axis direction. It is inserted through the extended lower shaft 37. The lower shaft 37 is provided with a flat screwing portion 37a, and the cam portion 160 is slidably positioned in the thrust direction with respect to the lower shaft 37 by a screw abutting against the screwing portion 37a.
Further, as shown in FIG. 9, the eccentric cam 161 and the triangular cam 162 can engage with the engaging portion of the horizontal feed rod 149, and the lower shaft 37 is arranged at a predetermined angle. At this time, the cam that moves in the thrust direction with respect to the lower shaft 37 while being engaged with the horizontal feed rod 149 can be switched to either one of the cams that engage with the horizontal feed rod 149.

When the elliptical feed movement locus (see FIG. 7A) is drawn on the upper feed leg 14, the cam portion 160 is moved to a position where the cam that engages with the horizontal feed rod 149 becomes the eccentric cam 161 for positioning. To do. As a result, as the lower shaft 37 rotates, vertical swing is applied to the bell crank 148 via the eccentric cam 161 and the horizontal feed rod 149, and the amount of movement corresponding to the inclination of the groove 153 of the feed amount conversion body 152 is increased. The bell crank 148 is also swung in the horizontal direction. As a result, turning force is applied to the horizontal feed shaft 39, and the upper feed foot 14 is elliptically shown in FIG. 7 (a) via the needle bar swing rod 59, the needle bar swing shaft 10 and the needle bar swing base 11. The movement trajectory of the feed will be drawn.
On the other hand, when the box feed movement locus (see FIG. 7B) is drawn on the upper feed leg 14, the cam portion 160 is moved and positioned so that the cam engaged with the horizontal feed rod 149 becomes the triangular cam 12. To do. Accordingly, the upper feed leg 14 draws a box feed movement locus shown in FIG. 7B as the lower shaft 37 rotates.

  According to the sewing machine 101 according to the second embodiment, the cams 161 and 162 are loosened by loosening the screws, moving the eccentric cam 161 and the triangular cam 162 integrally with the lower shaft 37 in the thrust direction, and fastening the screws again. Can be positioned. Therefore, the operation of switching the cam engaged with the horizontal feed rod 149 to either the eccentric cam 161 or the triangular cam 162 can be easily performed.

(Third embodiment)
Next, based on FIG.10 and FIG.11, 3rd embodiment to which this invention is applied is described.
In the sewing machine 201 according to the third embodiment, the eccentric cam 261 and the triangular cam 262 are adjacent to each other in the thrust direction, and a horizontal feed rod 249 as a transmission member includes a first engagement portion 249a that engages with the eccentric cam 261, and a triangular shape. A second engagement portion 249b that engages with the cam 262 and a first engagement that avoids the engagement between the eccentric cam 261 and the horizontal feed rod 249 when the triangular cam 262 engages with the second engagement portion 249b. The avoidance portion 249c and the second engagement avoidance portion 249d that avoids the engagement between the triangular cam 262 and the horizontal feed rod 249 when the eccentric cam 261 is engaged with the first engagement portion 249a are within the frame. The switching means moves the horizontal feed rod 249 so that the first engagement portion 249a and the eccentric cam 261 or the second engagement portion 249b and the triangular cam 262 are engaged. In the point that the movement trajectory of the upper feed leg 14 can be switched by switching to the position, and the slider stopper mechanism 270 is provided as a movement positioning means for positioning so as to hold each position. Different from the first and second embodiments.

The eccentric cam 261 and the triangular cam 262 are both fixed to the lower shaft 37, that is, coaxially, and both rotate integrally with the rotation of the lower shaft 37.
An upper end of the horizontal feed rod 249 is rotatably connected to a central portion of the bell crank 48, and a frame body portion 255 that engages with the eccentric cam 261 or the triangular cam 262 is provided at the lower portion. The eccentric cam 261 and the triangular cam 262 are inserted inside the frame body portion 255. Then, the horizontal feed rod 249 is centered on the connecting portion with the bell crank 48, one swinging end (see FIG. 11A) with which the eccentric cam 261 and the first engaging portion 249a engage, The cam 262 and the second engaging portion 249b are provided so as to be swingable at the other swing end (see FIG. 11C) where the cam 262 and the second engagement portion 249b are engaged.
The first engagement avoiding portion 249c is more than the first engaging portion 249a so that the horizontal feed rod 249 and the eccentric cam 261 are not engaged when the triangular cam 262 and the second engaging portion 249b are engaged. Is also wider. Similarly, the second engagement avoiding portion 249d is second engaged so that the horizontal feed rod 249 and the eccentric cam 261 are not engaged when the eccentric cam 261 and the first engagement portion 249a are engaged. The width is wider than the portion 249b.

The slider stopper mechanism 270 includes a support body 252 fixed in the sewing machine bed 50 and a link body 250 that connects the support body 252 and the horizontal feed rod 249.
One end of the link body 250 is rotatably connected to the lower end of the horizontal feed rod 249, and the other end of the link body 25 is a slide groove 252 a provided in the support body 252 so as to be orthogonal to the lower shaft 37. It is slidably fitted inside via a square piece 251. Further, the slide groove 252a is provided with a pin hole 252b with which the tip of the knock pin 253 engages, and the other end of the link body 250 and the tip of the knock pin 253 penetrating the square piece 251 can be freely engaged with and disengaged from the pin hole 252b. The horizontal feed rod 249 can be positioned at one oscillating end.

Based on FIG. 11, the operation of the sewing machine 201 according to the third embodiment will be described. First, when an elliptical feed movement locus (see FIG. 7A) is drawn on the upper feed leg 14, a horizontal feed rod 249 is disposed at one swinging end, and the eccentric cam 261, the first engagement portion 249a, Is positioned in an engaged state (see FIG. 11A). When the lower shaft 37 rotates in such a state, the triangular cam 262 rotates idly, so that the horizontal feed rod 249 is driven with the eccentric cam 261 as the original node. Then, an elliptical trajectory feed operation is performed on the upper feed foot 14 via the bell crank 48, the horizontal feed shaft arm 47, the horizontal feed shaft 39, the needle bar swinging rod 59, the needle bar swing shaft 10 and the needle bar swing base 11. Is granted.
On the other hand, when the box feed movement locus (see FIG. 7B) is drawn on the upper feed leg 14, the knock pin 253 is removed and the other end of the link body 250 is moved along the slide groove 252a (FIG. 11 ( b)). Then, the horizontal feed rod 249 is disposed at the other swing end, and the knock pin 253 is attached again with the triangular cam 262 and the second engagement portion 249b engaged, and the horizontal feed rod 249 is positioned (FIG. 11). (See (c)). When the lower shaft 37 rotates in this state, the eccentric cam 261 rotates idly, so that the horizontal feed rod 249 is driven with the triangular cam 262 as the original node. The upper feed leg 14 is given a box feed feed operation.

  As described above, according to the sewing machine 1 according to the third embodiment, the position of the horizontal feed rod 249 is switched by the slider stopper mechanism 270 and the feed operation to be applied to the upper feed leg 14 is simply performed by the elliptical feed. Can be easily switched to box feed.

In the first, second, and third embodiments, the general feed sewing machine is described as an example of the sewing machine having the upper feed mechanism. For example, the sewing product is fed by the upper feed leg and the lower feed dog. It can also be applied to a vertical feed sewing machine.
In addition, the movement positioning means in the third embodiment is configured by the slider stopper mechanism 270. For example, the other end of the link body 250 is used as a rotatable fixed point, and the link body 250 can be expanded and contracted. It may be configured.

It is a mechanism diagram which shows schematic structure of the sewing machine which is 1st embodiment. It is a side view showing a schematic structure around a needle bar swing base. It is a disassembled perspective view which shows the principal part structure in the sewing machine bed in 1st embodiment. It is a side view which shows a feed amount conversion body. It is a schematic explanatory drawing which shows the structure of a horizontal feed mechanism. It is a disassembled perspective view showing the relationship between a feed amount conversion body and a feed adjustment motor. It is explanatory drawing which shows the movement locus | trajectory of an upper feed leg. (A) shows an ellipse feed, and (b) shows a box feed movement locus. It is a disassembled perspective view which shows the principal part structure in the sewing machine bed in the sewing machine which is 2nd embodiment. It is explanatory drawing which shows the relationship between the eccentric cam and triangular cam in 2nd embodiment. It is a disassembled perspective view which shows the principal part structure of the sewing machine which is 3rd embodiment. It is operation | movement explanatory drawing which shows operation | movement of the sewing machine which is 3rd embodiment. It is the schematic which shows the shape of a triangular cam.

Explanation of symbols

1 Sewing machine (General feed sewing machine)
2 Sewing machine frame 4 Feed adjustment motor 8 Sewing arm 9 Upper shaft (spindle)
10 Needle bar swing shaft 11 Needle bar swing base 13 Needle bar 14 Upper feed foot 15 Eccentric cam 16 Link member 17 Link member 18 Bell crank 19 Link member 20 Presser foot 21 Link member 22 Transmission arm 23 Swing shaft 24 Rotation Connecting portion 25 Crank rod 26 Link member 27 Holding member 28 Adjustment block 29 Adjustment shaft 30 Projection portion 32 Rotating plate 33 Dial 37 Lower shaft 38 Vertical feed shaft 39 Horizontal feed shaft 44 Lower feed dog 50 Sewing bed 51 Cylinder 52 Feed amount conversion body 53 Groove 54 Square piece 59 Needle bar swing rod 60 Sewing machine motor 61 Eccentric cam 62 Triangular cam 90 Needle feed mechanism 91 Lower feed mechanism 94 Upper feed mechanism 96 Feed amount adjustment mechanism

Claims (4)

An upper feed leg that feeds the sewing product in contact with the upper side,
A vertical feed mechanism that imparts a vertical feed operation to the upper feed leg;
A circular eccentric cam fixed to the rotary shaft and imparting a reciprocating swinging motion in the horizontal direction to the upper feed leg; and a triangular cam fixed coaxially to the eccentric cam; A horizontal feed mechanism that gives a feed movement of
A transmission member that imparts a reciprocating swinging motion to the horizontal feed mechanism by following the eccentric cam or the triangular cam as an original section;
A switching mechanism that selectively switches between the eccentric cam and the triangular cam so as to be usable. The transmission member includes a first rod member that engages with the eccentric cam, and a second rod member that engages with the triangular cam,
The switching means moves the trajectory of the upper feed foot by switching the transmission state of the feed operation from either one of the first rod member or the second rod member to the connected state and the other to the released state. The sewing machine feed mechanism according to claim 1, wherein the sewing machine feed mechanism is switchable. The eccentric cam and the triangular cam are provided adjacent to each other in the thrust direction and movable and positioned in the thrust direction with respect to the rotation shaft,
The switching means moves the thrust position of the eccentric cam and the triangular cam with respect to the rotation shaft, and switches the cam that engages with the transmission member to the eccentric cam or the triangular cam, thereby switching the movement trajectory of the upper feed leg. 2. The sewing machine feed mechanism according to claim 1, wherein the sewing machine feed mechanism is provided. The eccentric cam and the triangular cam are adjacent to each other in the thrust direction,
The transmission member is
A first engagement portion that engages with the eccentric cam;
A second engagement portion that engages with the triangular cam;
A first engagement avoiding portion for avoiding engagement between the eccentric cam and the transmission member when the triangular cam engages with the second engaging portion;
A frame body portion having a second engagement avoiding portion for avoiding engagement between the triangular cam and the transmission member when the eccentric cam engages with the first engaging portion;
The switching means moves the transmission member to switch to a position where the first engagement portion and the eccentric cam or the second engagement portion and the triangular cam engage with each other. 2. The sewing machine feed mechanism according to claim 1, further comprising a movement positioning means that is provided so as to be switchable and that is positioned so as to hold each position.

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