JPS6053177A - Push-up apparatus of walking sewing machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention This invention has a presser foot that presses against the upper surface of the throat plate in the sewing section of the sewing machine, and a presser foot that performs four cloth feed movements in conjunction with the main shaft of the sewing machine on the needle plate adjacent to the presser foot. The present invention relates to a presser foot lifting device for an upper feed sewing machine, which has teeth and holds a presser foot and an upper feed dog apart from each other above a throat plate in connection with manual operation.

Conventionally, the presser foot lifting device for this type of top feed sewing machine has been designed to simultaneously rotate the top feed arm, which holds the top feed dog at its tip, and the presser foot, which holds the presser foot at its tip, in conjunction with the depressing operation of a pedal, etc. There is a known device in which the upper feed dog and the presser foot are raised by an equal fixed amount. According to this, the lower surface of the upper feed dog is raised with the lower surface of the upper feed dog protruding downward from the lower surface of the presser foot.
The lower surface of the protruding upper feed dog gets caught when loading and unloading the fabric, making the work cumbersome.In addition, in overlock sewing machines, the presser foot arm that supports the presser foot is normally attached to the machine frame so that it can rotate around a vertical axis. It has a mechanism to support the presser foot and release it laterally from the sewing machine sewing section, but as mentioned above, when the presser foot is raised, the upper feed dog and the presser foot rise by the same amount, so the presser foot does not move horizontally when the presser foot is raised. In order to rotate the presser foot, only the presser arm must be pushed down to prevent the presser foot from engaging with the upper feed dog before the presser foot is rotated, which makes the work complicated and has the disadvantage of significantly reducing work efficiency.

The purpose of this invention is to eliminate the drawbacks of the above-mentioned conventional devices.

(3) To explain this embodiment of Y light, at the rear of the sewing machine, the horizontal axis (
The middle part of a support shaft (not shown) having the axis A) in Fig. 1 is rotatably supported by a bearing (not shown) against the machine frame, and has a pin 1α parallel to the axis A at one end of the support shaft. While the effecting body 1 is fixed, a holder 2 is fixed to the other end, and a presser arm 3 is supported at the upper end of the holder 2 so as to be rotatable about a vertical axis. At the tip of the presser arm 3, there is a presser foot 4 formed with two rows of slots 4a into which tooth portions 23α of an upper feed dog 23, which will be described later, are fitted. The presser foot 4 is supported rotatably around the horizontal line that intersects with the fabric feed line, and the presser foot 4 is always attached to the throat plate (
(not shown) is subjected to an elastic force.

5. Working arm on the bearing supporting the support shaft. The supporting arm 6° and the connecting arm 7 are rotatably supported.

The operating arm 5 has an arcuate elongated hole 8 centered on the axis A of the support shaft formed at its base end, and the bottle 1α of the effecting body 1 is loosely fitted into the elongated hole 8. The working arm 5 has a protrusion 9 protruding from the upper part of the base end (17L) facing above the connecting arm 7, and one side edge of the protrusion 9 is bent upward to form a threaded hole 10α substantially along the cloth feeding direction.
is formed to form the connecting portion 10.

An operating lever 12 whose base end is fixed to a support shaft 11 rotatably supported on the machine frame along the cloth feeding direction has its tip connected to an operating body (not shown) such as a pedal, and its intermediate part connected via a connecting part 13. and is connected to the tip of the working arm 5. A screw 15 is adjustable by being screwed into a horizontal support plate 14 fixed to the machine frame, and the tip of the screw 15 can be secured to the upper edge of the operating lever so as to define the initial position of the operating lever 12. The coiled spring 16 provides an elastic force that rotates the operating lever 12 so that the upper edge of the operating lever 12 engages with the tip of the screw 15.

The connecting arm 7 has a connecting portion 17 that protrudes upward, faces the connecting portion 10 of the working arm 5, and has a hole 17α that communicates with the screw hole 10α, and a connecting portion 17 that protrudes toward the front in the cloth feeding direction and is bent into a substantially double-shape. It has a working part 18.

In FIG. 2, the stepped screw 19 has a distal end bulged in the outer circumferential direction to form a receiving portion 19α, a distal end shaft portion 19A loosely fitted into a hole 17α of the connecting arm 7, and a base having a diameter larger than that of the shaft portion 19h. Screw the end threaded portion 19c into the screw hole 10α of the working arm 5, and
9A is wound with a winding spring 20, and the receiving part 19α and the connecting part 17 are connected.
As a result, the connecting portion 17 is held between the end surfaces of the threaded portion 19c and the coil spring 20, so that the connecting arm 7 and the working arm 5 can rotate substantially integrally.

The upper feed arm 21 has its rear end in the cloth feed direction rotatably connected to the lower end of a horizontal swinging arm 22 that swings around an axis intersecting the cloth feed direction in conjunction with the main shaft of the sewing machine, and has an upper feed arm at its tip. tooth 23
is fixed so that its teeth 23α are opposed to the slots 4α of the presser foot 4.

A guide cam 21α is formed on one side end surface of the intermediate portion of the upper feed arm 21, and is a cam surface that can be engaged with the upper end of the operating portion f8 of the connecting arm 7. This guide cam 21. In all the swinging positions of the horizontal swinging arm 22, that is, in the entire horizontal movement range of the upper feed arm 21, the rise of the upper feed dog 23 due to the rotation of the connecting arm T, which will be described later, is expressed as the rotation of the connecting arm 7. The cam surface is formed so that it always has a constant amount with respect to the corner.

The support arm 6 has a screw hole 2 that protrudes upward and runs approximately along the cloth feeding direction.
4a, and a support portion 25 that protrudes forward in the cloth feeding direction and is connected to a vertical swing mechanism to be described later, and a screw 26 that is screwed into a screw hole 24α and whose tip engages with the machine frame. The rotation position of the support arm 60 is determined by screwing and adjusting the support arm 60. Shock absorber 2 fixed to the machine frame facing the tip of the screw 26
Reference numeral 7 is for cushioning the tip of the screw 26 from colliding with the machine frame when the support arm 6 swings, and is made of a material such as rubber.

A rocking body 28, which is rotatably connected to the tip of the support portion 25 of the support arm 6 about an axis that intersects with the cloth feeding direction, is connected to the tip of a rocking link (coupling means) 29 below the rotation axis. It is connected to be rotatable about an axis parallel to the rotation axis and is supported more than the rotation axis. Swing link 29
is a knife drive shaft 50 whose base end swings in conjunction with the main shaft of the sewing machine.
The piece 30 is connected to the upper feed arm 21 via a link 51 and swings in the clockwise direction A in FIG. Shape.

This rocking body 28. Swing link 29. The piece 30 constitutes a vertical swing mechanism.

Reference numeral 31 denotes a bifurcated guide body fixed to the machine frame and slidably fitted between both end surfaces of the tip of the upper feed arm 21. Reference numeral 32 denotes an adjustment means that engages with the upper part of the tip of the support part 25 of the support arm 6 and adjustably applies downward elastic force. The body 33 is arranged and fixed to the support part 25.

Although not shown, the link 51 has a structure in which the connecting hole for the knife drive shaft 50 is made into an elongated hole so that the connecting position can be adjusted and the swing stroke can be adjusted.

This light is structured like a memory, and its function will be explained next.

In the swing mechanism, the swing arm 22 swings around its upper end, thereby swinging the upper feed arm 21 in the horizontal direction, and the swing link 29 swings along arrow A, causing the swing body 2 to swing.
8 swings around the connection point of the support arm 6 with the support part 25,
The piece 30 supported by the swinging body 28 is swung in the vertical direction and transmitted to the upper feed arm 21 . As a result, the upper feed arm 21 performs four feed movements by combining vertical and horizontal directions. The thick part of the fabric, such as the stepped part, moves between the presser foot 4 and the throat plate, and the upper feed dog 2
3 is lifted up, but the piece 30 fitted with the upper feed arm 23
The rocking body 28 holding the support arm 6 is rotatably supported by the support portion 25 of the support arm 6, so that the support arm 6 is rotated against the elastic force of the adjustment means 32 about the axis (a) of the support shaft. Clockwise (
(Fig. 1) and absorbs the lifting force. When the support arm 6 returns by passing through the thick part of the cloth, the support arm 6
The tip of the screw 26 that is screwed into the machine frame, the adjustment means 32 and the support part 25 collide, but there is a shock absorber 27°33 between them.
It prevents vibration and sound.

The support shaft is given a rotational force in the clockwise direction in FIG. 1 by the elastic force acting on the presser arm 3 so as to press the presser foot 4 against the throat plate, and is also pressed against the tip of the support portion 25 of the support arm 6. The elastic force of the adjusting means 32 presses the tooth portion 23α of the upper feed dog 23 against the throat plate via the upper feed arm 21 that engages with the support arm 6.

Further, since the spring 20 of the stepped screw 19 is compressed between the receiving part 19α and the connecting part 11, the connecting arm 7 receives an elastic force in the clockwise direction in FIG. From this perspective, it is always non-coherent.

When the presser foot 4 is in pressure contact with the throat plate and the upper feed dog 23 is lowered, the support shaft and the working arm 5 are in the initial position (Fig. 4) where the pin 1α is located in the middle of the elongated hole 8, and the pin at this time is The position 1α is determined by the distance (△t) from the right end of the elongated hole 8 to the right end in FIG. The working arm 5 is rotated via the operating lever 12 by advancing and retracting the screw 15 that restricts the operating lever 12, so that the relationship between the pin 1a and the right end of the elongated hole 8 in the initial position is Make the interval adjustable.

When an operating body such as a pedal is pressed down and the operating lever 12 is rotated against the spring 16, the operating arm 5 moves along the axis 0 of the support shaft.
Rotate counterclockwise (Fig. 1) around the connecting portion 10.
The connecting arms T in the connected state at 17 rotate substantially simultaneously, and the operating portion 18 that engages with the guide cam 21a is connected to the upper feed arm 21.
push up.

The upper feed arm 21 rotates around the axis of connection with the swinging arm 22 so that the tip thereof rises, and the tooth 23α of the upper feed tooth 23 at the tip rotates.
rises above the throat plate. At the beginning of rotation of the working arm 5, the support shaft is stationary because no acting force is transmitted thereto. When the right end of the elongated hole 8 in FIG. 4 approaches the pin 1α due to the rotation of the operating arm 5, and the lower end surface of the tooth portion 23α of the upper feed dog 23 rises above the upper end surface of the presser foot 4 (FIG. 8). , the pin 1a is engaged with the right end surface of the elongated hole 8 (Fig. 5), and then the working body 1 (support shaft) is connected to the working arm 5 and rotates together, and the presser arm 3 is connected to the support shaft. The presser foot 4. from the throat plate (Figures 6 and 9). Due to the cam shape of the guide cam 21α with which the action portion 18 of the connecting body 7 engages, the amount of rise of the upper feed dog 23 during the initial rotation of the connecting arm 7 is kept constant regardless of changes in the swinging position of the swinging arm 22. I have to.

(//) Note that instead of the swinging mechanism of this embodiment, a mechanism as shown in FIG. 10.11 may be used as a second embodiment. That is, 33 is a sewing machine frame, 34 is a stepped portion 34α that supports the machine frame 33 so as to be able to slide in the vertical direction but not rotate, and bulges outward in the radial direction at the upper end, and a step portion 34α that is approximately on a line passing through the axis at the lower end. A cylindrical holder 35 has a support plane 34A cut out in the cylindrical shape, a shaft portion 35α loosely fitted to the upper end of the holder 34 on the lower ψ island, and a threaded portion 3 at the upper end.
5b is an adjustment shaft; 36 is a pedestal whose base end is fixed to the machine frame 33 and whose tip is screwed into the screw portion 35h of the adjustment shaft 35; 37;
Numeral 38 denotes a nut screwed into a conventional screw thread 35h above the pedestal 36, and a buffer body disposed between the stepped portion 34a of the holder 34 and the machine frame 33. Reference numeral 39 denotes a support shaft which has an axis substantially on the axis of the holder 34 and intersects with the cloth feeding direction and is fixed to the support plane 34h. Reference numeral 40 designates a support shaft whose upper end is rotatably supported around the support shaft 39 and whose lower end is a swing link. It is a rocking body rotatably connected to 29. 41 and 42 are arranged to sandwich the axis of the support shaft 39 and are spaced apart in the cloth feeding direction, and are rotatably supported (/2) relative to the swinging body 4o around an axis parallel to the support shaft 39; It is possible to engage with the upper end surface of the upper feed arm 21.
3 supports the swinging body 40 on the axis of the holding body 34 so as to be rotatable about an axis parallel to the support shaft 39, and holds the upper feed arm 21 between rollers 41 and 42 so that the lower surface thereof It is a roller that can be held in place.

Reference numeral 44 denotes a coiled spring compressed and disposed inside the holder 34 between the lower end of the adjustment shaft 35 and the upper end of the swinging body 40 via the buffer 45. Note that the support arm 6 is not required in the mechanism of this embodiment.

In such a configuration, the swinging of the swinging arm 22 causes the upper feed arm 21 to swing in the horizontal direction while being guided by the p-lars 41, 42, 43, and the swinging of the swinging link 29 causes the swinging body 40 to swing. swings around the support shaft 39, and the rollers 41,
The upper feed arm 21 held by 42 and 43 swings in the vertical direction, which causes the upper feed tooth 2 at the tip of the upper feed arm 21 to
3 performs four forward motions. When the cloth thick portion moves to the tooth portion 23α of the upper feed dog 23, the upper feed dog 23 is lifted.
The swinging body 40 pushes up the holding body 34 against the spring 44 via the p-lars 41 and 42 that engage with the upper feed arm 21, allowing the upper feed arm 21 to rotate.

When the upper feed arm 21 returns after the thick part of the cloth has passed, the holder 3
Shocks between the spring 44 and the machine frame 33 and between the spring 44 and the rocking body 40 are buffered by the shock absorbers 38 and 45, thereby preventing vibration and noise. Furthermore, when lifting the presser foot, the operating portion 1 of the connecting arm T that engages with the guide cam 21α is similar to the swinging mechanism of the present embodiment.
8, the upper feed arm 21 precedes the presser arm 3 (presser foot 4).
(Upper feed dog 23) rises by a certain amount.

Moreover, the swing mechanism of the third embodiment shown in FIG. 12 may be used instead of the second embodiment. That is, the supporting plane 34b at the lower end of the holding body 34 is extended downward, and the middle part of the L-shaped connecting link +7 is rotatably connected to the lower end. Roller 4 can be attached
b is supported rotatably around an axis that intersects with the cloth feeding direction. Further, the tip of the swing link 29 is rotatably connected to the lower end of the connecting link 41, and a piece 30 (configuration similar to this embodiment) fitted to the upper feed arm 21 is rotatably connected to the upper end of the connecting link 47. Support movably.

In such a configuration, horizontal swinging of the upper feed arm 21 due to swinging of the swinging arm 22 is allowed by the piece 30, and the swinging of the swinging link 29 causes the piece 30 to swing vertically via the connecting link 47. This causes the upper feed arm 21 to swing in the vertical direction, and the upper feed dog 23 performs four feed movements in the same manner as described above. By moving the upper feed dog 23 of the heavy portion to the tooth portion 23a, the upper feed dog 2
3 is pushed up, the holding body 3 is pushed up via the roller 46.
4 is pushed up against the spring 44, thereby allowing the upper feed arm 21 to rise.

Further, when lifting the presser foot, in the same way as described above, the action portion 18 of the connecting arm 7 that engages with the guide cam 21α causes the presser foot 3 (presser foot 4
), the upper feed arm 21 (upper feed dog 23) rises by a certain amount.

Further, in this embodiment, the support arm 6 is mounted on a bearing that rotatably fits the intermediate portion of the support shaft. Although the connection arm 7 is supported and the working arm 5 and the holder 2 are fixed to both ends of the support shaft, the working arm 5. Fix the holder 2 to both ends of the support shaft (/) and attach the support arms 6. The connecting arm 7 may be rotatably supported directly on the support shaft.

In addition, in this embodiment, the working arm 5. Support arm 6. Connecting arm 7. A holder 2 that supports the presser arm 3. However, the supporting arm 6 and the connecting arm I may be rotatably supported on another axis having an axis parallel to the supporting shaft, and may be connected so as to rotate in conjunction with the working arm 5. .

Further, in this embodiment, the guide cam 21 is attached to the upper feed arm 21.
α is formed to engage the tip of the acting portion 18 of the connecting arm 7, but the tip of the acting portion 18 may rotatably support a roller that engages with the guide cam 21α. The top surface of the tip has a cam shape that produces the same effect as a guide cam,
A roller or a pin may be arranged at the engaging portion of the upper feed arm 21.

Furthermore, in this embodiment, the working body 1 is fixed to the support shaft and the pin 1α of the working body 1 and the elongated hole 8 of the working ILs are fitted together, but the working arm 5 is attached to the holding body 2. A pin may be provided adjacent to the support shaft and protrude from the holder 2 (/l!17) in the axial direction, and this pin may be inserted into the elongated hole 8 of the working arm 5. An elongated hole may be formed in the body 1 or the holding body 2, and a pin may be formed in the working arm 5, so that they are fitted and arranged so as to produce the same effect as this embodiment.

Further, in this embodiment, the connecting arm 70 acting portion 18 is connected to the upper feed arm 2.
1, the support arm 6 is rotated about the axis A of the support shaft via the upper feed arm 21, and the upper feed dog 23 is raised. The support arm 6 is directly rotated by engaging the lower end surface of the tip of the support part 25,
1, the upper feed dog 23 may be raised.

As described above, according to the present invention, the working arm (5) has a base end supported rotatably about the rotational axis of the presser arm, and a distal end spaced apart from the base end in a horizontal direction connected to a manual operating member; Connecting means (V) disposed between the working arm and the upper feed arm to raise the upper feed dog from the throat plate in relation to the rotation of the working arm; By providing the operating means (1α, 8) that engages with each other and establishes a connected state at the rotation angle of the operating arm corresponding to the upward movement of the presser foot, the upper feed dog can be moved from the presser foot by operating the operating means. The structure is such that the upper feed dog rises first until the lower surface of the upper feed dog is located above the upper surface of the presser foot, and then the presser foot connects to the operating means and starts to rise, so the upper feed dog always Since it is located above the lower surface of the foot, it does not interfere with the loading and unloading of cloth, and since the upper feed dog is located above the presser foot, the presser arm can be rotated horizontally without having to push down the presser foot, increasing work efficiency. A significantly improved effect can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the upper feed device and lifting device of this embodiment, Fig. 2 is a front view of the upper feed arm up/out mechanism of the upper feed device, and Fig. 3 is a front view of the swing mechanism of the upper feed device. Figures 4 to 6 are explanatory diagrams explaining the connection state of the working arm and the support shaft, Figures 7 to 9 are explanatory diagrams of the upper feed arm up/out mechanism corresponding to Figures 4 to 6, and Figure 10 is FIG. 11 is a front view of the upper feeding device of the second embodiment, FIG. 11 is a perspective view of the main part of FIG. 10, and FIG. 12 is a perspective view of the main part of the upper feeding device of the third embodiment. Applicant's name Tokyo Heavy Equipment Industry Co., Ltd. (/7) 476-1 Japanese Patent Application Publication Sho GO-53177 (7)

Claims (1)

[Claims] A presser foot is fixed to the tip and the presser foot is brought into contact with and separated from the throat plate. The presser arm (3) is rotatably supported on the machine frame around a horizontal axis perpendicular to the cloth feeding direction, and normally receives an elastic force in the rotational direction that presses the presser foot against the throat plate, and the presser foot is attached to the tip of the presser arm (3). The upper feed dog facing the throat plate is fixed close to the foot, and the base end rotates around an axis that is parallel to the rotating axis of the presser foot and swings along the cloth feeding direction in conjunction with the main shaft of the sewing machine. In a sewing machine that has an upper feed arm (21) that allows the rotation of the upper feed arm (21) and a swing mechanism (28, 29) that is linked to the main shaft of the sewing machine and swings the tip of the upper feed arm in the vertical direction, A working arm (5) whose base end is supported so as to be rotatable and whose distal end horizontally spaced apart from the base end is connected to a manual operating member; A connecting means (7) for raising the upper feed dog from above the throat plate, and a connecting means (7) arranged in relation to the working arm and the presser foot, at a rotation angle of the working arm corresponding to the raising of the upper feed dog above the presser foot. A presser foot lifting device for a top-feed sewing machine, comprising operating means (1 and 8) that engage with each other and bring them into a connected state.