JPH04135273U - Sewing machine presser foot device - Google Patents

Abstract

(57) [Summary] [Purpose] To lock the rotation of a presser foot member in order to smoothly feed the work cloth, and to surely release the lock at the start of sewing. [Structure] The lock lever 29 engages with the engaged portion 23a of the presser foot member 23, and rotates the presser foot member 23 so that the cloth feeding side of the presser foot member 23 is raised by a predetermined amount with respect to the sewing machine bed surface 21. and a release position where the lock is released. The lock lever 29 is urged by the leaf spring 33 to both positions with a predetermined position between the locking position and the releasing position as a boundary. Further, when the presser foot member 23 rotates parallel to the sewing machine bed surface 21 with the start of sewing, the lock lever 29 is pushed beyond the boundary position toward the release position by the pressing portion 23b. . As a result, the lock lever 29 is urged to the release position by the leaf spring 33, and the lock is reliably released.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention includes a presser bar that is vertically movably supported on a sewing machine frame, and the presser bar or its It is rotatably supported by a member connected to the presser foot bar and placed on the sewing machine bed surface. A cloth presser member for pressing the work cloth, and a locking hand for locking the rotation of the cloth presser member. and a release hand for releasing the locking state of the work clamp portion locked by the locking means. The present invention relates to a presser foot device for a sewing machine having steps.

0002

[Conventional technology]

Conventionally, a presser foot device for this type of sewing machine has been disclosed, for example, in Japanese Patent Publication No. 17111/1983. has been disclosed. Its schematic configuration is as shown in FIG. A needle bar 57 with a needle 55 attached thereto is supported within the needle 53 so as to be movable up and down. It is driven vertically and reciprocally through a well-known mechanism. Also, a presser bar 59 is installed inside the machine frame 53. It is loosely fitted into a bushing 61 provided on the machine frame 53 at the bottom of the head 51 and supported so as to be movable up and down. held. A pin 63 bent at right angle is located outside the machine frame 53 of the bushing 61. has been set up. A holder 65 is fixed to the lower end of the presser bar 59, while an upper At the end, a leaf spring 69, which is fixed in the machine frame 53 in a known manner via a ball 67, is pressed. The elongated rod 59 is urged downward. The presser rod 59 and the plate spring 69 are held together by the ball-shaped recess. The position of the ball 67 is then fixed. Handle rotatably supported on the sewing machine frame 53 The bar 70 moves the presser bar 59 up and down via a well-known mechanism.

0003 A presser member 71 is rotatably supported by a pin 73 at the bottom of the holder 65. The presser member 71 is provided with a fork arm 71a extending to the left in the figure. A locking pin 75 is provided at the end of the fork arm 71a. On the other hand, cloth pressing The rotation range of the member 71 is regulated by the stopper surfaces 65a and 65b of the holder 65. has been done. A compression spring 7 disposed between the stopper surface 65a and the presser member 71 Reference numeral 7 applies a counterclockwise rotational moment to the presser member 71 in the figure. Also, An arm 65c is formed on the router 65, and a support shaft 79 provided on the arm 65c A locking element 81 is pivotally mounted. The locking pin 75 is located at the bottom of the locking element 81. It is provided with an engaging portion 81a that can be engaged with. The engaging portion 81a and the locking pin 75 are When engaged, the rotational moment generated by the compression spring 77 causes the locking pin 75 to The engaging portion 81a is frictionally coupled to lock the rotation of the cloth presser member 71.

0004 A torsion bar is inserted through the support shaft 79 and engaged with the arm 65c and the locking element 81. The screw 83 urges the locking element 81 counterclockwise in the figure, and the locking pin 75 and the front When the lock element 81 is released from the lock position where it engages with the engaging portion 81a, the lock Rotate the locking element 81 to the blocking position regulated by the stopper portion 65d of the holder 65. make it move. Furthermore, the upper part of the locking element 81 is provided with an inclined surface 81b.

[0005] A throat plate 8 is provided with a slit 85a on the sewing machine bed surface 84 below the presser foot member 71. 5 are arranged. The feed dog 87 passes through the slit 85a and performs the well-known four-movement feed. By doing so, the workpiece cloth N is fed in cooperation with the cloth presser member 71.

[0006] The presser bar 59 is raised to raise the cloth presser member 71 from the workpiece cloth N or throat plate 85. Immediately, the presser member 71 is brought into contact with the stopper surface 65b by the compression spring 77. Ru. When the presser bar 59 is further raised, the inclined surface 81b of the locking element 81 touches the pin 63. As the presser bar 59 rises, the pin 63 and the inclined surface 81b come into contact with each other, and the The locking element 81 is rotated against the torsion spring 83 into the locking position. At this time, the engagement The portion 81a and the locking pin 75 engage with each other. The torsion spring 83 then locks the locking element 8 1 in the counterclockwise direction in the figure, that is, the one that releases the lock of the presser member 71. However, the biasing force is due to the compression spring 77 applied to the locking pin 75. The friction force is set to be smaller than the friction force generated by the counterclockwise rotation moment. Therefore, the presser foot member 71 is held parallel to the sewing machine bed surface 84.

[0007] When sewing starts from the edge of the work cloth N, the edge is placed under the needle 55. After that, the presser bar 59 is lowered and the cloth presser member 71 is placed on the work cloth N. At this time, The pressure of the leaf spring 69 acts on the cloth presser member 71 via the presser rod 59, and the force is applied to the presser foot member 71. It is transmitted to the workpiece presser member 71 via 73. For this reason, the counterclockwise rotation mode in the figure is The material acts on the presser member 71 around the edge of the work cloth N below the needle 55. That is, the locking pin 75 urges the engaging portion 81a downward.

[0008] As soon as sewing is started and the edge of the work cloth N is sent behind the pin 73, the compression spring 7 7 and the plate spring 69 acting on the presser member 71 in the counterclockwise direction in the figure. -ment is gone. Then, the torsion spring 83 causes the locking pin 75 to engage the engaging portion. 81a, and the locking element 81 is rotated from the locking position to the blocking position. Then, the presser member 71 becomes rotatable.

[0009]

[Problem that the idea aims to solve]

However, in the cloth presser device having the above-mentioned configuration, the compression spring applied to the locking pin 75 is The rotation of the presser member 71 is controlled by the frictional force generated by the rotational moment caused by 77. Since the work cloth N is locked, the cloth presser is caused to vibrate before it is sent behind the pin 73. The locked state of the material 71 may be released. In the released state, press the presser bar 59. When lowered, the cloth presser member 71 rotates due to contact with the work cloth N. When the cloth feeding side of No. 1 is biased against the throat plate 85 and sewing starts, the workpiece cloth The front end of N is blocked by the cloth feeding side of the cloth presser member 71 and is not fed, resulting in poor sewing. Koru. Also, when the rotational moment acting on the presser member 71 disappears, the screw Since the lock is released by the spring 83, the work cloth N is sent behind the pin 73. The locked state may not be released even if the If it is not released, the workpiece cloth N being sewn will be If the cloth presser member 71 is unable to press the work cloth N depending on the difference in level, a sewing defect may occur. There was a problem.

0010 The present invention was made in order to solve the above-mentioned problems, and it Even if there is vibration in the locked state, the locking is maintained, and the processed fabric is To provide a presser foot device for a sewing machine that reliably releases a locked state when it is fed later. aimed to.

[0011]

[Means to solve the problem]

To achieve this object, the present invention is directed to a press that is supported on the sewing machine frame so as to be movable up and down. a presser bar, and a presser bar rotatably supported by the presser bar or a member connected to the presser bar; A cloth presser member for pressing the work cloth placed on the thin bed surface, and the cloth presser portion. a locking means for locking the rotation of the material; and the presser foot portion locked by the locking means. In the presser foot device of a sewing machine, the presser foot device has a release means for releasing the locked state. It has an engaging part that can be engaged with an engaged part provided on the cloth presser member, and At the same time, the cloth feed side of the presser foot member is raised by a predetermined amount with respect to the sewing machine bed surface. a locking position where the presser foot member is locked, and a locking position where the presser foot member is released from the engaged portion and the locking position is set as shown in FIG. The presser bar or the presser bar is connected to the presser bar so as to be rotatable between the release position and the release position. a locking member supported by the member and a predetermined position between the locking position and the release position; a biasing means for biasing the locking member to both positions with the boundary between the two positions; The locking member is provided on the cloth presser member so as to be able to press the locking member that has been pressed. When the presser foot member rotates parallel to the sewing machine bed surface, the locking portion pushing the material beyond the boundary position toward the release position against the urging force of the urging means; A pressing section is provided.

0012

[Effect]

In the presser foot device of the sewing machine of the present invention having the above configuration, the presser bar or its presser The presser member rotatably supported by the member connected to the presser rod is provided with an engaged portion. The locking member has an engaging portion that can be engaged with the engaged portion. The material feed side of the presser foot member is raised by a predetermined amount relative to the sewing machine bed surface. a locking position where the presser foot member is locked, and a locking position where the presser foot member is released from the engaged portion and the locking position is set as shown in FIG. the presser bar or a part connected to the presser bar so as to be rotatable between a release position and a release position; supported by the material. Then, the locking member is moved from the locking position to the front by the biasing means. It is biased to both positions with a predetermined position between it and the release position as a boundary. Also, presser foot The member is provided with a pressing portion capable of pressing the locking member rotated to the locking position. , when sewing starts, the presser member rotates to be parallel to the sewing machine bed surface. When moving, the locking member resists the urging force of the urging means and presses the boundary against the urging force of the urging means. is pushed beyond the field position toward the release position. As a result, the locking member The lock is released by being biased toward the release position.

[0013]

【Example】

An embodiment embodying the present invention will be described below with reference to the drawings.

[0014] As shown in FIG. 1(a), a needle bar on which a needle 5 is attached is located inside the machine frame 3 of the sewing machine head 1. 7 is supported to be able to move up and down, and is driven back and forth up and down via a well-known mechanism (not shown). be done. Further, a presser bar 9 is supported on the machine frame 3 so as to be able to move up and down. In FIG. 1(b), the presser bar holder 11 having the arm portion 11a extending to the right is the presser bar holder. It is fixed with a set screw 13. The presser bar holding screw 13 and the machine frame 3 A presser spring 15 attached to the presser bar 9 always urges the presser bar 9 downward. Said ar The arm part 11a is in contact with a presser foot lifter 17 rotatably supported on the machine frame 3, and a sewing position for pressing the work cloth to perform sewing by rotating the presser foot lifter 17; Cloth loading and unloading position for loading and unloading processed fabrics and thick cloth for loading and unloading thick processed fabrics The presser bar 9 can be moved up and down in three positions including the in/out position.

[0015] A pair of walls (only one shown) is vertically provided on the presser foot member 23. A pin 25 is installed between them. This presser member 23 is fixed to the lower end of the presser bar 9. The holder 19 is rotatably and detachably connected to the lower part of the holder 19 via the pin 25. It is. Further, a lock lever 29 is attached to the side of the holder 19 by a stepped screw 31. The lock lever 29 has a long hole 2 formed therethrough. A pin 27 is provided to protrude from the side of the holder 19 passing through 9b. The lock lever At the lower part of the presser member 29, there is an engaged member that protrudes from the wall of the cloth presser member 23 toward the cloth feeding side. A recess 29a that can be engaged with the portion 23a is formed.

[0016] Then, the engaged portion 23a and the recessed portion 29a are engaged, and the surface of the sewing machine bed is 21 so that the cloth feeding side of the cloth presser member 23 is raised by a predetermined amount. The position where 3 is locked is called the locking position (see FIG. 2(a)). Further, the recess 29a is disengaged from the engaged portion 23a to release the locking position from the release position (FIG. 2( b)). The lock lever 29 is rotated by the pin 27 and the elongated hole 29b. movement is restricted, and the lock lever 29 is rotatable between the locking position and the release position. It is.

[0017] Further, a plate spring 33 having a chevron-shaped portion 33a is attached to the lock lever 29. It is. The chevron-shaped portion 33a engages with the pin 27 to move the locking position to the unlocking position. The lock lever 29 is urged to both positions with predetermined positions between the two positions as boundaries. Furthermore, the lock lever 29 is provided with a wavy portion 29c. Adjust the presser foot lifter 17 to the above thickness. When the presser bar 9 is moved to the cloth loading/unloading position, the wavy portion 29c is in contact with the contact portion 3a provided on the sewing machine frame 3, and the lock lever 29 is Rotate to the locked position.

[0018] The pressing portion 23b that can press the lock lever 29 rotated to the locking position is a presser foot. It is provided on the cloth feeding side of the member 23. The pressing portion 23b is pressed when sewing starts. When the presser foot member 23 rotates parallel to the sewing machine bed surface 21, , urging to the locking position due to the engagement between the chevron-shaped portion 33a of the plate spring 33 and the pin 27; Push the lock lever 29 beyond the boundary position toward the release position against the force. . Therefore, the lock lever 29 is urged toward the release position, and the work presser member 23 is locked. It will definitely be canceled.

[0019] A throat plate 3 is provided with a slit 34a on the sewing machine bed surface 21 below the presser foot member 23. 4 are arranged. Then, the feed dog 35 passes through the slit 34a and By dynamically feeding, the workpiece cloth N is fed in cooperation with the cloth presser member 23.

[0020] Next, the operation of the cloth feed device of the sewing machine configured as described above will be explained with reference to the drawings. do.

[0021] As shown in Fig. 3(a), when sewing a thick work cloth N from its front end, In order to place the work cloth N on the sewing machine bed surface 21 below the needle 5, the presser foot lifter 17 is placed on the thick cloth. When the presser bar 9 is moved to the in/out position, as the presser bar 9 is raised by the operation, the abutment By contacting the wavy portion 29c with the portion 3a, the mountain-shaped portion 33 of the leaf spring 33 The lock lever 29 is moved against the biasing force toward the release position due to the engagement between the lock lever 29 and the pin 27. is rotated beyond the boundary position toward the locking position. At this time, the presser member 23 When the cloth feeding side is raised by a predetermined amount with respect to the sewing machine bed surface 21, the recess 29 a is engaged with the engaged portion 23a, and due to the urging force of the plate spring 33 toward the locking position. The cloth presser member 23 is locked.

[0022] Next, as shown in FIG. 3(b), the work cloth N is placed on the sewing machine bed surface 21 below the needle 5. After placing the presser foot 17, the presser foot lifter 17 is placed at the sewing position where the presser foot member 23 presses the work cloth N. Manipulate. At this time, the cloth feeding side of the presser foot member 23 has been raised from the throat plate 34. It is in a state.

[0023] Then, when sewing is started, as shown in FIG. 3(c), the feed dog 35 and the cloth The workpiece cloth N is smoothly fed by the cooperation with the presser member 23, and the front end of the workpiece cloth N is When passing the pin 25, the presser foot member 23 changes from the locked state to the sewing machine bed surface 21 (needle It rotates parallel to the plate 34). At that time, the pressing portion 23b Resisting the biasing force of the spring 33 toward the locking position, the terminal moves beyond the boundary position to the release position. Push the lock lever 29 to the side. Then, the leaf spring 33 moves the lock lever 29 from the above-mentioned position. The locking is released by biasing it to the released position.

[0024] In addition, as shown in FIG. 4(a), during sewing work, the cloth feeding side of the cloth presser member 23 is If there is a step in the workpiece fabric N where the interrupt. Then, as shown in FIG. 4(b), the presser foot lifter 17 is moved to the above-mentioned position for entering and exiting the thick cloth. When the presser member 23 is operated in the position, the rotation of the presser member 23 is locked as described above. Figure 4(c) ), the presser foot is raised to the sewing position where the cloth presser member 23 presses the work cloth N. After operating step 17, sewing begins. Then, as described above, the presser member 23 is The lock is released.

[0025] In this way, the fabric feeding device of the sewing machine of the present invention is suitable for starting sewing thick work cloth N, If there is a step such that the cloth feed side of the presser foot member 23 is extremely raised during manufacturing, Operate the presser foot lifter 17 to the thick cloth loading/unloading position. Then, the cloth feed of the cloth presser member 23 Rotation of the presser member 23 is locked so that the folding side is raised by a predetermined amount. And the presser foot When the sewing machine 17 is moved to the sewing position to start sewing, the workpiece cloth N is fed and the cloth is pressed. The locking member 23 is rotated parallel to the sewing machine bed surface 21, and the lock is released. This prevents the work cloth N from being fed in easily and causing sewing defects. .

[0026] Further, the locking position and the release position bordering on the boundary position by the plate spring 33 Even if there is vibration in the locked state, the locking is maintained due to the biasing of the presser foot member 2 3 becomes horizontal to the sewing machine bed surface 21, the locking is reliably released.

[0027] Note that in the present invention, the lock lever 29 is provided with the wavy portion 29c; 9c is not provided, the presser foot lifter 17 is operated to the cloth loading/unloading position or the thick cloth loading/unloading position. The operator may operate the lock lever 29 to rotate it to the locking position. stomach.

[0028] Further, in the present invention, the chevron-shaped portion 33a of the leaf spring 33 is connected to the elongated hole 29b of the lock lever 29. The lock lever is engaged with the pin 27 that penetrates through the holder 19 and protrudes from the side of the holder 19. 29 is biased toward the locking position and the releasing position with the boundary position as a boundary. However, you can also do the following: Lock lever 2 is used instead of pin 27 and leaf spring 33. A pair of pins are provided on the axis passing through the center of rotation of 9. Attach the spring. However, one pin across the center is the lock lever 29. The other pin is provided in the holder 19. Then, the lock lever 29 is aligned with the axis line. The locking position is biased between the locking position and the release position. In this way, the present invention Various modifications are possible without departing from the spirit.

[0029]

[Effect of the idea]

As is clear from the above explanation, in the present invention, the presser foot member is in the locked state. In order to press the presser foot member against the edges and steps of the workpiece cloth on the cloth feed side, When lowering it, the locked state will not be released due to vibration like in the past, Sewing is started and the ends and stepped portions of the workpiece fabric are smoothly placed on the cloth feeding side of the presser foot member. It becomes movable, and as it moves, the presser foot moves against the surface of the sewing machine bed. Push the lock lever beyond the boundary position toward the release position as it is rotated in parallel. This ensures that the lock is released and the presser member rotates according to the unevenness of the fabric to be processed. Can press cloth.

[Brief explanation of the drawing]

FIG. 1(a) is a front view of a presser foot device of a sewing machine embodying an embodiment of the present invention. (b) is a side view of a presser foot device of a sewing machine embodying an embodiment of the present invention.

FIG. 2(a) is a front view of the presser foot device in the locking position. (b) is a front view of the presser foot device in the release position.

FIG. 3(a) is an explanatory view showing the state when the presser foot lifter is operated to the thick cloth loading/unloading position before starting sewing. (b) is an explanatory diagram showing a state in which the cloth feeding side of the presser foot member, which has been lowered by operating the presser foot lifter to the sewing position before starting sewing, presses the work cloth. (c) is an explanatory diagram showing a state when the locking of the presser foot member is released with the start of sewing.

FIG. 4(a) is an explanatory diagram showing a state when there is a step such that the cloth feeding side of the presser foot member is extremely raised during sewing. (b) is an explanatory diagram showing a state when sewing is interrupted and the presser foot lifter is operated to the thick cloth loading/unloading position. (c) is an explanatory view showing the state when the presser foot lifter is operated to the sewing position.

FIG. 5 is a front view of a presser foot device of a conventional sewing machine.

[Explanation of symbols]

9 Presser bar 23 Presser foot member 23a Engaged part 23b Pressing part 27 pin 29 Lock lever 29a recess 29b hole 33 Leaf spring 33a Mountain-shaped part

Claims (1)

[Scope of utility model registration request] 1. A presser bar supported on a sewing machine frame so as to be movable up and down, and a work cloth rotatably supported by the presser bar or a member connected to the presser bar, and placed on the sewing machine bed surface. a presser foot member for pressing the presser foot, a locking means for locking rotation of the presser foot member, and a release means for releasing the locked state of the presser foot portion locked by the locking means. In the presser foot device of a sewing machine, the presser foot device includes an engaging portion that can engage with an engaged portion provided on the presser foot member, and engages with the engaged portion and presses against the sewing machine bed surface. rotatable between a locking position in which the cloth presser member is locked so that the cloth feeding side of the cloth presser member is raised by a predetermined amount, and a release position in which the cloth presser member is disengaged from the engaged portion and released from the lock; a locking member supported by the presser bar or a member connected to the presser bar;
a biasing means that biases the locking member to both positions with a predetermined position between the locking position and the release position as a boundary; and a biasing means capable of pressing the locking member rotated to the locking position. is provided on the presser foot member, and when the presser foot member rotates parallel to the sewing machine bed surface at the start of sewing, the locking member is moved against the biasing force of the biasing means. A presser foot device for a sewing machine, comprising: a pressing portion that presses the material beyond the boundary position toward the release position.