JP2009285206A - Let-off arm type covering chain stitch sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a let-off arm type covering chain stitch sewing machine which meets a request for improving an operation speed by satisfactorily lubricating the inside of a head and effectively preventing dust from entering the inside of the head. <P>SOLUTION: A connection rod 6 of a knife drive mechanism and a presser bar lifter link 43 of a presser bar lifter mechanism are disposed at the outside of the distal end part of a sewing machine arm 10, and are covered with a side face cover 9 fitted to the distal end face of the sewing machine arm 10. An opening provided in the back face of the head 12 in order to extend the connection rod 6 and the presser bar lifter link 43 is covered with the side face cover 9, whereby lubrication in the head 12 is facilitated, and the dust is prevented from entering the inside of the head 12. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a feed-out arm-shaped flat stitch sewing machine having various drive mechanisms including a needle bar drive mechanism in a head portion connected to a tip end portion of a sewing machine arm incorporating a sewing machine main shaft.

  For example, a delivery arm-shaped flat stitch sewing machine used for stitching a crotch part of briefs and shorts is provided with a sewing arm and a sewing bed extending in different directions on the upper and lower parts of the sewing machine frame, respectively. A head portion is connected to the tip portion of the sewing machine arm in a direction substantially orthogonal to the sewing arm, and a plurality of needles are attached to the lower end of a needle bar suspended from the head portion toward the tip of the sewing machine bed. A presser foot is attached to the lower end of the presser bar that is attached and is hung from the head portion in the vicinity of the needle bar (see, for example, Patent Document 1).

  The stitching with the feed-out arm-shaped flat stitch sewing machine is made up of the presser foot attached to the lower end of the presser bar and the top end of the sewing machine bed. Multiple needles that move between the needle plate and the needle bar, and move up and down together with the needle bar by feeding from the base end to the tip of the machine bed by the operation of the feed mechanism inside the machine bed. This is performed in the procedure of sewing together by the cooperative operation with the internal looper.

  The presser bar is supported in the head portion so as to be movable in the vertical direction, and is urged downward by the spring force of the presser spring. The presser foot attached to the lower end of the presser bar is a spring of the presser spring. The cloth is being sewn down by the force and presses the fabric being sewn, and the presser lift mechanism that can be operated from the outside raises the presser bar against the spring force of the presser spring, raising the fabric. The presser foot is released. The presser lifting mechanism is supported outside the sewing machine arm and is operated to swing by the user. The presser lifting mechanism transmits the swinging of the presser lifting lever to the presser bar in the head, and applies a lifting force to the presser bar. And a presser foot lifting link.

  The presser foot of the feeding arm-shaped flat stitch sewing machine has a pair of presser feet that extend in parallel with each other at the front part of the presser body attached to the lower end of the presser bar, and these presser feet are opposed to each other. A scalpel device configured to trim the edges of the fabric fed to the needle drop position by the fixed scalpel and the movable scalpel held in such a manner is provided.

The movable knife of the knife device is attached to a knife bracket that is supported in the middle of the presser bar so that it can be rotated about the same axis. By repeatedly rotating the knife bracket, the holding part of the presser foot is used as a guide. The reciprocating motion makes sliding contact with the fixed knife and cuts and aligns the edge of the cloth that has reached the sliding contact position. The female bracket is extended to the inside of the head portion, and has an operating arm projecting radially in the extension portion. This operating arm is connected via a connecting rod to a female swing shaft that rotates repeatedly within a predetermined angle range in response to transmission from the sewing machine main shaft, and the rotary swing of the female swing shaft is operated via the connecting rod. A knife driving mechanism is configured to transmit to the arm and repeatedly rotate the knife bracket.
Japanese Patent Publication No. 7-57272

  The feeding arm-shaped flat stitch sewing machine configured as described above is provided with the above-described presser lifting mechanism, and the presser lifting link of the presser lifting mechanism is provided inside the presser lifting lever and the head portion located outside the sewing machine arm. In order to connect the presser bar positioned, the presser bar is extended into the head portion through an opening provided on the back surface of the head portion which is connected to the sewing machine arm.

  Further, the feeding arm-shaped flat stitch sewing machine includes the above-described knife driving mechanism, and the connecting rod of the knife driving mechanism needs to be adjustable in length in order to adjust the reciprocating range of the movable knife. Therefore, in the prior art, the head of the connecting rod having the base end connected to the protruding portion is projected to the outside of the tip of the sewing machine arm through the opening provided on the back surface of the head portion in the same manner as the presser lifting link. The length of the connecting rod can be adjusted from the outside of the sewing machine arm by extending it into the section and connecting it to the female swing shaft.

  Further, as shown in FIG. 1 of Patent Document 1, the female bracket of the female drive mechanism is a U-shaped member that is detoured around the front of the head and extends inward. Is formed with an opening for receiving the female bracket.

  Thus, the feeding arm-shaped flat stitch sewing machine has openings on the front surface and the back surface of the head portion, and the presence of these openings is provided in the head portion such as a needle bar drive mechanism for moving the needle up and down. In addition to making the mechanism difficult to lubricate, dust generated in the sewing environment may enter the head portion through the opening and hinder the operation of the mechanism, making it difficult to meet the demand for higher operating speed. There is a problem.

  The present invention has been made in view of such circumstances, and makes it possible to satisfactorily lubricate the mechanism in the head part and effectively prevent the intrusion of dust into the head part to meet the demand for higher operating speed. It is an object of the present invention to provide a feeding arm-shaped flat stitch sewing machine.

  The feeding arm type flat stitch sewing machine according to the first aspect of the present invention includes a presser bar supported by the head at the tip of the sewing machine arm, a presser foot attached to the lower end of the presser bar, and a presser foot held by the presser foot. A movable knife, a presser lifting mechanism that conveys the swing of a presser lifting lever provided outside the sewing machine arm to the upper part of the presser bar that extends inward of the head unit, and raises the presser foot, and an outer part of the sewing machine arm The reciprocating rotation of the female swinging shaft protruding to the head is transmitted to the female bracket supported in the head portion using the presser bar as a support, and the movable knife attached to the protruding end of the female bracket to the outside of the head portion is used. A feeding arm-shaped flat stitch sewing machine having a reciprocating knife driving mechanism, which is attached to the sewing machine arm and connects the knife swinging shaft to the knife bracket. Characterized in that the de-and the presser foot lifting lever includes a cover member for covering a part or the whole of the outside of the presser foot lifting link connected to the presser bar.

  In the present invention, the outer side of the connecting rod for connecting the knife swinging shaft to the knife bracket and the presser lifting link for connecting the presser lifting lever to the presser bar is covered with a cover member, and the connecting rod and the presser lifting link are extended into the head portion. Therefore, the opening provided on the back surface of the head portion is closed, the inside of the head portion is well lubricated, and dust is prevented from entering the head portion.

  In the delivery arm type flat stitch sewing machine according to the second invention of the present invention, the cover member in the first invention covers the entire connecting rod including the connecting end with the female swing shaft, and the presser lifting link The cover member extends through the inside and outside, and a part of the side away from the presser lifting lever is covered with the cover member.

  According to the present invention, the connecting rod that performs a complicated operation in response to repeated rotation of the female swing shaft and covers the whole including the connection end with the female swing shaft is covered with the presser foot. The presser foot lifting link that performs simple reciprocating movement according to the swing of the lever covers only a part of the tip side away from the connection side with the presser foot lifting lever, and covers the inside and outside of the head part with a small size cover. Effectively cut off by the member.

  A feeding arm-type flat stitch sewing machine according to a third aspect of the present invention is a seal plate that is circumferentially attached to a through hole provided in the cover member of the second invention and elastically contacts the peripheral surface of the presser foot lifting link that passes through the through hole. It is characterized by providing.

  A feeding arm type flat stitch sewing machine according to a fourth aspect of the present invention is fixed at one end to a peripheral portion of a through hole provided in the cover member and has the other end at a midway portion of the presser lifting link passing through the through hole. A fixed bellows is provided.

  In these inventions, the midway part of the presser link that penetrates the cover member is sealed with a sealing plate or bellows made of an elastic material such as rubber or resin, and the head part is lubricated more favorably into the head part. Effectively prevent the intrusion of dust.

  A delivery arm-type flat stitch sewing machine according to a fifth aspect of the present invention includes a second cover member that is attached to the head portion and covers a protruding portion of the female bracket to the outside of the head portion. To do.

  In the present invention, the protruding portion of the female bracket to the outside of the head portion is covered with the second cover member, and at least a part of the opening provided in the front of the head portion is closed to extend the female bracket to the outside. Prevents dust from entering the unit.

  In the feeding arm type flat stitch sewing machine according to the present invention, the opening provided in the head portion for passing the constituent members of the knife driving mechanism and the presser foot lifting mechanism is closed by the cover member, so that the mechanism in the head portion is well lubricated. In addition, the intrusion of dust into the head portion can be effectively prevented, and a mechanism that operates at a high speed, such as a needle bar drive mechanism for moving the needle up and down, is well lubricated. The present invention has excellent effects, such as being able to reliably prevent dust from entering and meeting the demand for higher operating speed.

  Hereinafter, the present invention will be described in detail with reference to the drawings illustrating embodiments thereof. FIG. 1 is an external perspective view showing the overall configuration of a delivery arm type flat stitch sewing machine according to the present invention.

  As shown in the figure, the delivery arm-shaped flat stitch sewing machine includes a sewing machine arm 10 extending in one direction at the upper part of the sewing machine frame 1 and a narrow cylindrical sewing machine bed 11 extending in a different direction from the sewing machine arm 10 at the lower part of the sewing machine frame 1. I have. A head portion 12 having a hollow rectangular block shape is connected to the tip of the sewing machine arm 10 in a direction substantially orthogonal to the sewing machine arm 10.

  Below the head portion 12, a presser bar 13 is supported in a suspended manner toward the tip of the sewing bed 11 facing each other, and a presser foot 14 is attached to the lower end of the presser bar 13. The presser bar 13 is supported so as to be movable up and down as will be described later. The presser foot 14 descends onto a needle plate 15 installed at the tip of the sewing machine bed 11 by the downward movement of the presser bar 13, and holds a cloth (not shown) between the presser foot 15 and the needle plate 15. The cloth held between the presser foot 14 and the needle plate 15 is fed from the base of the sewing machine bed 11 toward the tip side by the operation of a feeding mechanism (not shown) provided inside the sewing machine bed 11, and this feed is applied. Are stitched together by a plurality of needles (not shown) that move up and down in synchronization with the sewing machine.

  The presser foot 14 is provided with a pair of left and right presser feet 14a, 14a extending toward the base (fabric introduction side) of the sewing machine bed 11. The presser foot 14a, 14a includes a fixed knife 16 and a movable knife 17 ( A scalpel device is provided with (see FIG. 3).

  In FIG. 1, the base of the fixed knife 16 is shown. The fixed knife 16 is a plate-like knife fixedly held by one presser foot 14a, and has a blade at a tip portion protruding toward the other presser foot 14b. The movable knife 17 is held by the other presser foot 14b and reciprocates in the direction substantially orthogonal to the presser legs 14a, 14b by the operation of the knife driving mechanism configured as described below, and moves to the blade of the fixed knife 16. As is well known, the edges of the fabric to be introduced are aligned between the presser feet 14a and 14b in a sliding manner. The trimmed fabrics are piled up and down by the action of the guide means located on the downstream side of the scalpel device, sent to the needle drop position and stitched together.

  FIG. 2 is a cross-sectional view showing a support structure for the presser bar 13. As shown in the figure, the presser bar 13 is supported by a lower bush 2 passing through the lower wall 12 b of the head portion 12 in the vertical direction via a rotating cylinder 20. The lower bush 2 can be formed integrally or separately with the head portion 12. The upper part of the presser bar 13 is inserted and supported by the upper bush 3 that penetrates the upper wall 12a of the head part 12 in the vertical direction. In this way, the presser bar 13 is supported at two locations separated vertically by the upper bush 3 and the lower bush 2, and can move up and down under the guidance of these bushes 3 and 2.

  The upper portion of the upper bush 3 protrudes to the outside of the head portion 12 by an appropriate length, and an adjusting screw 30 is screwed to the protruding end portion. A presser spring 31 using a coil spring is interposed between the lower end of the adjusting screw 30 and the upper end of the presser bar 13. The presser spring 31 applies a downward spring force to the presser bar 13 and biases the presser foot 14 attached to the lower end portion of the presser bar 13 downward. In FIG. 4, the presser foot 14 is not shown.

  The magnitude of the spring force of the presser spring 31 can be adjusted by rotating the knob 32 provided at the upper end of the adjusting screw 30 and changing the screwing amount of the adjusting screw 30. This adjustment is performed to change the presser force of the cloth between the presser foot 14 and the needle plate 15, and the adjusted presser force is maintained by tightening a lock nut 33 provided in the middle of the adjusting screw 30. can do.

  A presser bar holder 4 is fixed in the middle of the presser bar 13 between a support position by the lower bush 2 and a support position by the upper bush 3, and the rear side of the presser bar holder 4 is substantially horizontal. A swing lever 40 is pivotally supported so as to be swingable around the support shaft 41. The swing lever 40 includes an action piece 42 that extends forward and contacts the lower surface of the presser bar holder 4.

  Also, one end of a presser foot lifting link 43 indicated by a two-dot chain line in the drawing is connected to the tip of the swing lever 40 extending upward from the support portion. The other end of the presser foot lifting link 43 is extended to the rear outer side of the head portion 12 and is connected to a presser foot lifting lever 44 supported on the outer surface of the tip end portion of the sewing machine arm 10 as described later. In FIG. 1, a connecting portion between the presser lifting lever 44 and the presser lifting link 43 is shown.

  The presser foot lifting lever 44 is an operation lever that is supported so as to be swingable about an axis parallel to the swing lever 40 and is configured to swing a predetermined angle in accordance with an appropriate operation by the operator. When the presser foot 14 is raised, the presser foot lifting lever 44 is swung. As is well known, the presser foot lifting lever 44 can be operated by operating the operation end of the knee push plate, the foot pedal, etc. by mechanical transmission means such as a link or a wire. It can also be performed by the operation of the actuator in accordance with the switch operation.

  The swinging operation of the presser lifting lever 44 is transmitted to the swinging lever 40 via the presser lifting link 43, and the swinging lever 40 swings counterclockwise as indicated by an arrow in FIG. By this swinging, the action piece 42 provided on the swing lever 40 acts on the presser holder 4, the presser bar 13 is pushed up via the presser lifter holder 4, and the presser foot 14 attached to the lower end of the presser bar 13. Rises. The presser foot raising operation for raising the presser foot 14 in this way is performed when setting the cloth before sewing on the needle plate 15 or when removing the cloth after sewing from the needle plate 15.

  The presser bar holder 4 is engaged with a guide bar provided on one side of the presser bar 13 in parallel with the presser bar 13, and also performs an action of restricting the rotation of the presser bar 13 about its axis. Due to this action, the presser foot 14 is not likely to rotate due to the action force from the fabric held between the needle plate 15 and the presser foot 15.

  A rotating cylinder 20 interposed between the presser bar 13 and the lower bush 2 protrudes at an appropriate length above and below the lower bush 2. A hook bracket 21 is provided at the lower end portion of the rotating cylinder 20 protruding outside the head portion 12, and this hook bracket 21 is attached to a decorative thread mechanism 22 (see FIG. 1) provided on the upper part of the presser foot 14. It is connected. A connection bracket 23 is fitted to the upper end portion of the rotating cylinder 20 extending inside the head portion 12. The connection bracket 23 is connected to a drive mechanism inside the sewing machine arm 10 via a connection rod (not shown).

  With the above configuration, the rotating cylinder 20 is repeatedly rotated around the axis according to the operation of the drive mechanism transmitted to the connection bracket 23 at the upper end, and this repeated rotation is provided at the lower end of the rotating cylinder 20. This is transmitted to the decorative thread mechanism 22 via the hook bracket 21. The decoration thread mechanism 22 performs a known operation of arranging the decoration thread on the upper surface of the cloth being sewn by transmission from the hook bracket 21.

  FIG. 3 is a perspective view of a scalpel drive mechanism that reciprocates the movable scalpel 17. In the figure, 18 is a female swing shaft as a drive shaft of the female drive mechanism. The knife swinging shaft 18 is supported horizontally in the sewing machine arm 10 and rotated repeatedly around the shaft within a predetermined angle range by transmission from the sewing machine main shaft 8 (see FIGS. 4 and 5). Is the axis. A swing arm 19 extending outward in the radial direction is fixed to one end of the knife swing shaft 18. The swing arm 19 swings in response to repeated rotation of the knife swing shaft 18.

  In the figure, 5 is a female bracket. The female bracket 5 is connected by a U-shaped connecting body 50, and includes cylindrical support cylinders 5a and 5b that are coaxially arranged at an appropriate distance. One support cylinder 5a is provided with an operating arm 51 extending radially outward, and the other support cylinder 5b is provided with a fixing bracket 52.

  As shown in FIG. 2, the female bracket 5 is configured such that one support cylinder 5 a is fitted on the upper part of a later-described rotating cylinder 20 that protrudes inside the head portion 12, and the upper end of the connecting cylinder 23 and the lower end of the rotating cylinder 20. The other supporting cylinder 5b is fitted on the lower part of the rotating cylinder 20 which is held between the upper surface of the bush 2 and protrudes to the outside of the head portion 12, and the lower surface of the lower bush 2 and the lower end of the rotating cylinder 20 are It is mounted between the hook bracket 21 so that the connecting body 50 of both support cylinders 5a and 5b bypasses the front surface (right end surface in FIG. 2) of the head portion 12 and communicates the inside and outside of the head portion 12. It is.

  The female bracket 5 attached as described above is supported by the presser bar 13 via the rotary cylinder 20 and can be rotated coaxially with the presser bar 13. A sliding plate is interposed between the support cylinders 5a and 5b, the lower bush 2 and the rotary cylinder 20, so that the female bracket 5 can be smoothly rotated.

  As shown in FIG. 3, the operating arm 51 provided on the upper support cylinder 5 a is connected to the swing arm 19 of the female swing shaft 18 by the connecting rod 6 at both ends including the ball joints 60, 60. With the above configuration, the female bracket 5 repeatedly rotates around the axis in accordance with the repeated rotation of the female swing shaft 18 transmitted through the swing arm 19, the connecting rod 6, and the operating arm 51. As shown in FIG. 3, the ball joints 60 and 60 at both ends of the connecting rod 6 are attached so as to be capable of adjusting the position in the axial direction by screws. This position adjustment is carried out to change the length of the connecting rod 6 and finely adjust the reciprocating range of the movable knife 17 which will be described later. In order to make this adjustment possible, the connecting rod 6 that connects the knife swinging shaft 18 and the operating arm 51 is arranged outside the front end of the sewing machine arm 10 as will be described later.

  As shown in FIG. 3, the fixing bracket 52 provided on the lower support cylinder 5 b includes a fixing seat 53 that extends around the front and extends further downward from the extended end. The movable knife 17 is attached to the fixed seat 53 via a knife base 54. The movable knife 17 is a plate-shaped knife having a blade at one end in the longitudinal direction, the other end is fixed to the knife base 54, and is attached to the front position of the presser bar 13 so as to be substantially orthogonal to the presser bar 13. It is.

  As described above, the movable knife 17 attached in this way is passed through the guide portion provided on one presser foot 14b of the presser foot 14, and is held so as to be able to reciprocate in a direction substantially perpendicular to the presser foot 14b. Yes. The reciprocating motion of the movable knife 17 occurs under the guidance of the guide portion in response to the swinging of the fixed bracket 52 accompanying the repeated rotation of the knife bracket 5. The movable knife 17 is urged downward by a coil spring 55 provided on the knife table 54. The coil spring 55 strengthens the pressing of the movable knife 17 against the fixed knife 16 and acts to surely cut the fabric at the sliding contact position of both the knife 16, 17.

  As shown in FIGS. 1 and 2, a rectangular opening 70 continuous with the lower edge is provided in the lower portion of the front plate 7 that seals the front surface of the head portion 12. The opening 70 has a width larger than the swing range of the U-shaped connecting body 50 that connects the upper and lower support cylinders 5a and 5b of the female bracket 5, and the connecting body 50 of the female bracket 5 The support cylinders 5a and 5b extending to the front surface of the head portion 12 through the opening 70 and extending downwardly and positioned inside and outside the head portion 12 as shown in FIG.

  A front cover (second cover member) 71 is attached to the lower front surface of the front plate 7. As shown in FIGS. 1 and 2, the front cover 71 covers the front surface of the opening 70 formed in the front plate 7 over the entire width and length of the opening 70. Accordingly, the internal and external communication of the head portion 12 can be sufficiently blocked while allowing the female bracket 5 to swing, preventing dust from entering the head portion 12, and lubricating the head portion 12. This can be carried out without causing leakage of the lubricant to the outside.

  4 and 5 are external perspective views of the distal end portion of the sewing machine arm 10. As shown in FIG. 4, a sewing machine main shaft 8 protrudes from the tip of the sewing machine arm 10 and is connected to a sewing machine motor (not shown) via a transmission pulley 80 fitted to the protruding end. As shown in FIG. 5, one side of the protruding portion of the sewing machine main shaft 8 is covered with a side cover 9 (cover member).

  FIG. 4 shows a state in which the side cover 9 is removed. As shown in this figure, the end of the female swing shaft 18 is located at the tip of the sewing machine arm 10 at one side of the protruding portion of the sewing machine main shaft 8. The swing arm 19 is fixed to the projecting end portion. As described above, one end of the connecting rod 6 is connected to the swing arm 19, and the connecting rod 6 extends forward (to the right in FIG. 4) along the front end surface of the sewing machine arm 10, and the head As described above, it is inserted into the inside of the portion 12 through the opening provided on the back surface, and is connected to the female bracket 5 as shown in FIG. 3, and the movable knife 17 is reciprocated by transmission from the knife swinging shaft 18 as described above. A knife drive mechanism is configured.

  The length of the connecting rod 6 arranged as described above can be adjusted from the outside, and the reciprocating range of the movable knife 17 can be finely adjusted. An oil receiving pan 61 is attached below the connecting rod 6. The oil receiving pan 61 has an appropriate inclination with the front facing down and is extended inside the head portion 12, and includes a support portion for the female swing shaft 18, a connecting portion between the swing arm 19 and the connecting rod 6, and the like. It receives the lubricating oil leaking from the head and returns it into the head portion 12 by the inclination of the bottom surface.

  A lever base 45 is fixed to the upper surface of the rear part at the front end of the sewing machine arm 10, and the presser lifting lever 44 of the presser lifting mechanism described above is attached to the lever base 45. The presser lift lever 44 is an L-shaped arm as shown in the figure, and is pivotally supported by a lever base 45 by a support shaft 46 provided at a bent portion, and one end of the presser lift link 43 extends in the middle of one side extending upward. It is connected.

  Further, the rocking lever 40 of the presser lifting mechanism described above is pivotally supported on the inner side of the head portion 12 at the front end portion of the sewing machine arm 10. The swing lever 40 is connected to the other end portion of the presser lifting link 43 that extends forward along the front end surface of the sewing machine arm 10 and enters the head portion 12. A presser lifting mechanism is configured to transmit the swinging operation of the lever 44 to the swinging lever 40 via the presser lifting link 43 and swing the swinging lever 40 to raise the presser foot 14.

  As shown in FIG. 4, the side cover 9 has the connecting rod 6 of the female drive mechanism arranged on the outer side of the distal end portion of the sewing machine arm 10 as described above and the connecting portion with the swing arm 19 and the female swing shaft 18. A box-shaped cover having a shape that covers the protrusion and covers the part of the presser lift link 43 on the side away from the presser lift lever 44. A bracket 90 provided on a part of the periphery is attached to the sewing machine arm 10. As shown in FIG. 5, it is mounted so that the opening on the back surface of the head portion 12 is closed over the entire area.

  The front end of the presser foot lifting link 43 is extended into the side cover 9 through a through hole 91 provided at a corresponding position of the side cover 9, and is connected to the swing lever 40 as shown in FIG. . A sealing plate made of an elastic material such as rubber or soft resin is provided around the periphery of the through hole 91, and is elastically contacted with the outer periphery of the middle part of the presser lifting link 43 inserted through the through hole 91. The insertion part of the lever 44 is sealed.

  The delivery arm type flat stitch sewing machine according to the present invention includes the side cover 9 mounted as described above, and the side cover 9 includes the connecting rod 6 of the female drive mechanism and the presser lifting link 43 of the presser lifting mechanism. In order to extend the distance, an opening provided in the back surface of the head portion 12 is closed, and communication between the inside and the outside of the head portion 12 by this opening is blocked. Accordingly, various types of motion mechanisms provided in the head unit 12 such as the needle bar drive mechanism can be lubricated satisfactorily without the risk of lubricant leakage, and dust in the head unit 12 can be prevented. It is possible to prevent intrusion, and it is possible to cope with an increase in operating speed.

  The side cover 9 is not limited to the shape shown in FIGS. 4 and 5, and may have an appropriate shape that covers a part or all of the connecting rod 6 and the presser lifting link 43 and can close the opening on the back surface of the head portion 12. it can. The side cover 9 shown in FIGS. 4 and 5 covers the outside of the connecting rod 6 including the protruding portion of the female swing shaft 18, the support portion of the female swing shaft 18, the swing arm 19 and the connecting rod 6. It is possible to satisfactorily perform the necessary lubrication on the connecting portion.

  The presser foot lifting link 43 covers only a part, but this presser foot lifting link 43 only performs a simple operation of moving in the axial direction in response to the swing of the presser foot lifting lever 44. It is possible to cope with this by simply providing a small-diameter through hole 91 that can allow slight deflection of 43, and the internal and external communication of the head portion 12 can be effectively blocked. In addition, the configuration in which the insertion portion of the presser lift link 43 is sealed by the arrangement of the seal plate described above enables the head portion 12 to be more reliably shut off from inside and outside without hindering the movement of the presser lift link 43. Lubrication in the portion 12 can be carried out satisfactorily, dust can be reliably prevented from entering the head portion 12, and the operation speed can be increased.

  The side cover 9 shown in FIGS. 4 and 5 is shown as having a fixing bracket 90 at one location on the periphery, but similar brackets are provided at a plurality of locations on the periphery, and each has a sewing arm 10. It is desirable to fix to the front end surface of the screw. By attaching sealing means to one or both of the contact portion between the peripheral edge of the side cover 9 and the opening of the head portion 12 and the close contact portion between the peripheral edge of the side cover 9 and the front end surface of the sewing machine arm 10, a side cover is provided. Although it becomes possible to seal the inside and outside of 9 more reliably, the interposition of this sealing means is not essential.

  FIG. 6 is an external perspective view of the distal end portion of the sewing machine arm 10 showing another embodiment of the present invention. Also in this figure, a side cover 9 is attached to the outer surface of the tip end portion of the sewing machine arm 10 so as to cover the outer side of the presser lifting link 43 and the connecting rod 6 and close the opening of the back surface of the head portion 12. In this embodiment, the presser lifting link 43 is a round bar-like link, and is extended into the side cover 9 through a through hole (not shown) provided at the corresponding position. Is sealed with a bellows 92 having one end fixed to the peripheral edge of the opening and the other end fixed to the midway part of the press-up link 43.

  The bellows 92 can be deformed following the reciprocating motion of the presser foot lifting link 43 that occurs with slight swinging, and while allowing the motion of the presser foot lifting link 43, the inner and outer sides of the side cover 9, that is, the inner and outer sides of the head portion 12. Can be blocked more reliably.

1 is an external perspective view of a delivery arm-shaped flat stitch sewing machine according to the present invention. It is sectional drawing which shows the support structure of a presser bar. It is a perspective view of the knife drive mechanism which reciprocates a movable knife. It is an external appearance perspective view of the front-end | tip part of the sewing machine arm which shows the state which removed the side cover. It is an external appearance perspective view of the front-end | tip part of the sewing machine arm which shows the state which attached the side cover. FIG. 5 is an external perspective view of a tip end portion of a sewing machine arm 10 showing another embodiment of the present invention.

Explanation of symbols

5 Female bracket 6 Connecting rod 8 Side cover (cover member)
10 Sewing arm
12 Head
13 Presser bar
14 Presser foot
17 Movable knife
18 Female swing shaft
43 Presser lifter link
44 Presser lifter lever
71 Front cover (second cover member)
91 Through hole
92 Bellows

Claims (5)

A presser bar supported by the head at the tip of the sewing machine arm, a presser foot attached to the lower end of the presser bar, a movable knife held by the presser bar, and a presser lifting lever provided outside the sewing machine arm. Oscillation is transmitted to the upper part of the presser bar extending inward of the head part to support the presser bar and a presser lifting mechanism for raising the presser foot and a reciprocating rotation of a female swinging shaft protruding outside the sewing machine arm. In a delivery arm type flat stitch sewing machine comprising: a female drive mechanism which transmits to a female bracket supported in the head portion as a body and reciprocally moves the movable knife attached to the projecting end of the female bracket to the outside of the head portion ,
A cover rod that is attached to the sewing machine arm and that covers a part or all of a connecting rod that connects the knife swing shaft to the knife bracket and a presser lifting link that connects the presser lifting lever to the presser bar from the outside. The feeding arm shape flat stitch sewing machine.   The cover member covers the entirety of the connecting rod including a connecting end with the female swing shaft, and the presser lifting link extends through the cover member inward and outward, and is separated from the presser lifting lever. 2. The delivery arm-shaped flat stitch sewing machine according to claim 1, wherein a part of the outer side is covered with the cover member.   The delivery arm-shaped flat stitch sewing machine according to claim 2, further comprising a sealing plate that is circumferentially attached to a through hole provided in the cover member and elastically contacts a peripheral surface of the presser lifting link that passes through the through hole.   The feeding arm-shaped flat shape according to claim 2, further comprising a bellows having one end fixed to a peripheral portion of a through hole provided in the cover member and the other end fixed to a middle portion of the presser lifting link passing through the through hole. Sewing machine.   The delivery arm-shaped flat stitch sewing machine according to any one of claims 1 to 4, further comprising a second cover member attached to the head portion and covering a protruding portion of the female bracket to the outside of the head portion.

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