JPH0412792A - Cloth holding device of sewing machine - Google Patents

Abstract

PURPOSE:To prevent the presser foot supporting body from turning at the time of sewing, and also, to simply execute the change of a presser foot by small force by providing an energizing member for suppressing the turning of the presser foot supporting body, when the presser foot is provided in a cloth holding position by turning of the presser foot supporting body, and an energizing force suppressing member for suppressing the energizing force of the energizing member, when a holding rod is in an ascent position. CONSTITUTION:When a presser foot is provided in a cloth holder 3 position by turning of a presser foot supporting body 12, an energizing member suppresses turning of the presser foot supporting body. Also, when a holding rod 4 is in an ascent position, an energizing force suppressing member suppresses energizing force of the energizing member. Therefore, when the holding rod 4 is in a descent position, that is, when a sewing work is executed, turning of the presser foot supporting body 12 is suppressed by the energizing force of the energizing member, cloth can be held down satisfactorily by a presser foot 8, and on the other hand, when the holding rod 4 is in an ascent position, the presser foot supporting body 12 can be turned by small force. In such a way, when the holding rod is in an ascent position, it is unnecessary to hold cloth by the holding foot, therefore, in such a state, by suppressing the energizing force of the energizing member, the presser foot can be changed simply.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a presser foot device for a sewing machine that is equipped with a plurality of presser feet and is capable of replacing the presser foot used depending on the sewing work.

[Prior Art] Conventionally, a plurality of presser feet are attached to the periphery of a presser foot support formed in a disc shape, and the center of the presser foot support is attached to a mounting member fixed to the tip of a presser bar. A presser foot device is known in which the presser foot support is rotatably mounted so that the presser foot used in sewing operations can be replaced (Japanese Patent Application Laid-Open No. 62-204789).

In addition, in this type of device, a mounting member fixed to the tip of the presser bar is provided with a pole, and the presser foot support is formed with a recess into which the pole fits when each presser foot is placed at the presser foot position. When the presser foot is in the presser position, this pole is pressed against the four parts of the presser foot support using a biasing member such as a leaf spring, so that the presser foot support rotates during sewing. It prevents you from doing so.

[Problems to be Solved by the Invention] When the rotation of the presser foot support is prevented in this way, it is possible to prevent the presser foot from coming off the presser foot position during sewing with the sewing machine, and to improve the sewing operation. However, when rotating the presser foot support and replacing the presser foot, the presser foot support must be rotated ε against the biasing force of the biasing member. First, there was a problem of poor workability when replacing the presser foot. It has also been considered to automatically replace the presser foot using a motor, etc., but conventional methods require a large amount of force to rotate the presser foot support as described above. There is also the problem that in order to be able to automatically replace the legs, a large motor with a large rotation torque is required.

SUMMARY OF THE INVENTION Therefore, the present invention provides a cloth presser device in which the presser foot can be replaced by rotating the presser foot support as described above, which can prevent the presser foot support from rotating during sewing, and can also replace the presser foot. This was done with the purpose of making it possible to do this easily with a small amount of force.

``Means for Solving the Problems'' That is, the present invention, which has been made to achieve the above object, includes a presser bar that is attached to an arm of a sewing machine so as to be movable up and down; a presser foot support that can sequentially arrange a plurality of presser feet at the presser foot position; and a biasing force suppressing member that suppresses the biasing force of the biasing member when the presser foot is in the raised position.

[Function] In the presser foot device of the sewing machine of the present invention configured as described above, when the presser foot is disposed at the presser foot position by rotation of the presser foot support, the biasing member is pressed against the presser foot support. Suppress the rotation of. Further, when the presser foot is in the raised position, the biasing force suppressing member suppresses the biasing force of the biasing member. Therefore, when the presser foot is in the lowered position, that is, when performing sewing work, the biasing force of the biasing member suppresses the rotation of the presser foot support, allowing the presser foot to properly press the fabric. When the presser foot is in the raised position, the presser foot support can be rotated with a small force.

In other words, in the present invention, when the presser foot is disposed at the presser foot position, if the presser foot is in the lowered position, it is necessary to press the material with the presser foot, but if the presser foot is in the raised position, the presser foot must be pressed. There is no need to press the cloth with your feet, so in this state (
The biasing force of the biasing member is suppressed so that the presser foot can be easily replaced.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

As shown in FIG. 2, the arm 2 of the sewing machine is provided with a presser foot bar 4 to which a cloth presser device 3 is attached, and a needle bar 6 to which a sewing machine needle 5 is attached so as to be movable up and down. There is. The presser bar 4 is supported in the arm 2 so as to be movable up and down via a presser bar storage case 7 shown in FIG. , the presser foot 8 provided on the presser foot device 3 is biased downward so as to press the work cloth placed on the bed 9 of the sewing machine with a predetermined pressure.

As shown in FIG. 1, the presser foot device 3 is formed into a circular umbrella shape, and includes a presser foot support 2 having a plurality of protrusions 1 protruding from the outer wall for attaching the presser foot, and a presser foot support 2 protruding from the outer wall. body] 2 rotatably supported, and (2) a mounting member for removably fixing the cloth presser device 3 to the presser bar 4] 3.

The mounting member] 3 is formed in an umbrella shape like the presser foot support 12, and a hole 14 for fixing the presser foot support 2 is formed in the center thereof.

In addition, a hole 15 having a diameter larger than that of the hole 4 is formed in the center of the presser foot support 12.
2 and the mounting member 13, and insert a stepped screw into the hole 14, ]5]
6 and tightening the step screw 16 with the nut 7, the presser foot support 12 can be attached to the mounting member 3.

On the other hand, on the mounting member 13, a plurality of protrusions 11 for attaching the presser foot are positioned on an extension line of the axis of the presser bar 4 as the presser foot support 12 rotates, and the presser foot 8 attached to the protrusion 11 is A ball 9 is provided which fits into a recess 18 formed in the presser foot support 12 when the presser foot is placed at the presser foot position. This ball 19 is connected to the nut [7] and the mounting member]
By the two leaf springs 20 and 21 fixed between 3 and 3,
It is pressed against the presser foot support 12 side, and due to this urging force, the ball ]9 bites into the recess]8 and firmly fixes the presser foot support 12.

As shown in FIG. 3, in this embodiment, presser foot support] 2
The presser foot support 12 is rotated by attaching different presser feet 8 to each of the three projections 1 through the mounting screws 11a, and used for sewing work. The presser foot 8 can be selected from three types of presser feet.

In addition, the inner and outer leaf springs 2 of the two leaf springs 20 and 21 mentioned above
0 is a ball] so that it protrudes upward from the presser position of 9.
It is formed larger than the inner leaf spring 2]. On the other hand, on the arm 2 side, when the presser foot 4 is in the raised position, as shown in FIG. 2 or FIG. An engagement protrusion 22 serving as a biasing force suppressing member that is displaced in the direction of arrow A shown in the figure is fixed. Therefore, when the presser foot 4 is in the raised position, that is, when the presser foot 8 is not sewing the outer thread 2 from the cloth presser position, the urging force that urges the ball 9 toward the presser foot support 12 is generated. As a result, the force of the ball [9] biting into the recess 18 is reduced, and the presser foot support [2] can be rotated with a small force.

Further, on the periphery of the presser foot support 12, the presser foot support 1
2 itself becomes a gear that rotates around the step screw 16,
Teeth 12a are formed, and when the presser bar 4 is in the raised position as shown in FIG. This allows the presser foot support 12 to rotate.

As shown in FIG. 2, the gear 23 connects the air cylinder 24 attached to the arm 2 and the rod 2 of the air cylinder 24.
A cam mechanism 2 that converts the reciprocating motion of 5 into a rotational motion of a predetermined angle.
The presser foot 8 used in the sewing work can be changed by this rotation.

As explained above, in this embodiment, 1. When the presser foot bar 4 is in the lowered position, the ball 8 for stopping the rotation of the presser foot support 2 is urged toward the presser foot support 12 by the two leaf springs 20 and 21. When the predetermined presser foot 8 attached to the presser foot support 12 is at the cloth presser position, the ball 19 will firmly bite into the recess]8, preventing the presser foot support 12 from rotating during sewing work. can.

Furthermore, when the presser foot bar 3 is in the raised position and no sewing work is being performed, the outer leaf spring 20 engages with the engagement protrusion 22 to press and bias the ball]8 toward the presser foot supporter]2. Therefore, the pressing force of the ball 8 toward the presser foot support 12 is obtained only by the leaf spring 2, and the presser foot support 2 can be rotated with a small force. Therefore, the drive device 27 that rotates the presser foot support 2 to change the presser foot 8 can use a device with a small driving force, and this drive system can be downsized.

In this embodiment, the drive device 27 is used to rotate the presser foot support 12, but if the present invention is applied to a device that manually rotates the presser foot support 2, the presser foot support ] Since the force for rotating the presser foot can be reduced, work efficiency when changing the presser foot can be improved.

Further, in this embodiment, the gear 23 is rotated using a drive device 27 consisting of an air cylinder 24 and a cam mechanism 26.
Although the presser foot support 12 is driven to rotate, the gear 23 may be rotated by a motor, for example.
Alternatively, two motors may be attached to the presser foot device 3 side, and the presser foot support 2 may be directly driven to rotate by the motors. Also in this case, if the presser foot support 2 is rotated when the presser bar 4 is in the raised position, the same effect as in the above embodiment can be obtained.

In this embodiment, when the presser bar 4 is in the raised position, the leaf spring 20 is always engaged with the engagement protrusion 22, and the leaf spring 20 is displaced in the six directions of the arrows. Even if the engaging protrusion 22 is made movable by the solenoid 32 as shown in a), and the presser bar 4 is in the raised position, as shown in the same figure (b),
The engagement protrusion 22 may act only when necessary to displace the leaf spring 20 in the six directions of the arrows. As a result, when the presser bar 4 is in the raised position, the leaf spring 20 is attached to the mounting member 1.
The burden added to 3 can be reduced.

That is, when the presser foot 4 is in the raised position, the engagement protrusion 22
If the presser foot support 12 is constantly engaged with the leaf spring 20, the stepped screw 16 portion of the presser foot support 2 will be pressed by the leaf spring 20, and the connecting portion between the presser foot support 12 and the mounting member 13 will be damaged. However, if the solenoid 32 is used to move the leaf spring 20 in the direction of the arrow only when the presser foot support 2 is rotated, this problem can be solved.

[Effects of the Invention] As detailed above, according to the presser foot device of the sewing machine of the present invention, when the presser foot is in the raised position, the biasing force of the biasing member that suppresses the rotation of the presser foot support is This not only prevents the presser foot support from rotating during sewing work, but also allows the presser foot support to be rotated with a small force when the presser foot is in the raised position. It becomes possible to easily change the presser foot used for sewing work. Further, since the presser foot can be changed with a small force, when the presser foot support is rotated by a drive device such as a motor, the drive device can be downsized.

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a partial sectional view showing the configuration of the presser foot device of the embodiment;
Figure 2 (a) is a front view of a sewing machine equipped with this presser foot device, Figure 2 (b) is a left side view of the same machine, and Figure 3 explains the presser foot attachment part of the presser foot support. Explanatory diagram, FIG. 4 is a partial cross-sectional view showing the engaged state of the presser foot device and the arm side member when the presser foot is in the raised position, and FIG.
It is a partially enlarged view showing another example of the figure.

Claims (1)

[Scope of Claims] A presser foot that is attached to the arm of a sewing machine so as to be movable up and down, and a presser foot that is rotatably attached to the presser foot and that can sequentially arrange a plurality of presser feet at the position of the presser foot by rotation. a support member; an urging member that suppresses the rotation of the presser foot support when the presser foot is placed at the presser foot position due to the rotation of the presser foot support; and when the presser foot is in the raised position; A presser foot device for a sewing machine, comprising: a biasing force suppressing member that suppresses the biasing force of the biasing member.