JPH0223246Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a workpiece feeding device that feeds out a workpiece held between clamps so as to be sewn along a guide groove formed in the clamp.

[Prior Art] Currently, various proposals have been made for sewing machines that can execute predetermined sewing patterns without the need for human intervention.
A relatively inexpensive and simple structure that can perform this so-called pattern sewing operation is one in which the workpiece is sandwiched between two plates in which guide grooves are formed, and the workpiece is sewn along the guide grooves. It has been known. As a device for feeding a workpiece together with this clamp, there is a conventional device shown in FIG. 2, for example.

This device consists of two plates C1 and C2 of clamp C.
A clamp guide b protruding from the throat plate is inserted into a groove-shaped guide groove Cg bored in the clamp C, and the clamp C is fed out by rotating a roller r brought into contact with the peripheral edge of the clamp. In addition, b
1 is a needle hole into which a sewing machine needle N is inserted, and T is a sewing machine table. Further, the roller r uses the rotational force of the main shaft as a driving source, and rotates in synchronization with the vertical movement of the sewing machine needle. In other words, when the sewing machine needle rises, the roller r
rotates to feed the workpiece W, and when the sewing machine needle N descends, the roller r does not rotate and the feed of the workpiece W is stopped, so-called intermittent feeding. Further, when the curve starting point of the guide groove Cg reaches the clamp guide b during the sewing operation, the switch s detects this, and the arm a rotates to apply a rotational force to the clamp C about the clamp guide b. By this rotational force and the feeding by the roller r, the clamp C is sent out along the guide groove Cg to form a curved stitch (hereinafter referred to as a curve stitch).

[Problems to be solved by the invention] As described above, according to the conventional workpiece feeding device, it is possible to perform both straight stitches and curved stitches, but it is also possible to perform both straight stitches and curved stitches. It was impossible to form a square stitch (hereinafter referred to as a corner stitch). This is due to the following reasons. In other words, in order to perform corner stitching, it is necessary to temporarily stop the sewing operation when it reaches the bent part of the guide groove and rotate the sewing machine needle. However, in the conventional device described above, In order to perform feeding, roller r was configured to rotate in synchronization with the vertical movement of the sewing machine needle, so when the vertical movement of the sewing machine needle was stopped, roller r also became unable to rotate, and was clamped by arm a. This is because even if C is rotated, the clamp C cannot be rotated due to friction between the peripheral edge of the roller r and the clamp C.
Therefore, when sewing items that require corner stitching, such as collars and flaps, for example, the clamp C must be manually rotated at the corner of the guide groove, resulting in low productivity. The dot was hot.

This invention was developed by focusing on the above-mentioned problems, and aims to provide a workpiece feeding device that can realize appropriate feeding for all sewing patterns such as straight stitching, curved stitching, and corner stitching. shall be.

[Means for solving the problem] This invention has a linear feed mechanism that intermittently feeds the clamp that holds the workpiece in a linear direction in accordance with the vertical movement of the sewing machine needle, and a one-way clutch, and a motor that feeds the clamp in one direction only. and a roller that rotates, and when the bent portion of the guide groove reaches the needle drop position, the operation of the feed mechanism is stopped and the motor is activated.

[Function] In this invention, in the case of straight stitching, the linear feed mechanism feeds the clamp in a straight direction. At this time, as the clamp moves, the rollers in contact with the side edges of the clamp idle because the clutch mechanism is in the released state. When the bent part of the guide groove reaches the needle drop position, the sewing machine moves up and down and the linear feed mechanism stops operating, while the roller rotates and rotates the clamp by a predetermined angle around the needle drop position. Perform straight stitch again.

[Embodiment of the invention] An embodiment of the invention will be described below with reference to FIG. Note that in the drawings, the same parts as in the above-mentioned conventional example are given the same reference numerals.

In the figure, reference numeral 1 denotes a clamp rotating roller with a built-in one-way clutch mechanism.In the feeding direction (in the direction of the solid line arrow in the figure), the clutch mechanism is in an open state and can rotate, and in the opposite direction, the clutch mechanism can be rotated. A mechanism is applied to restrict rotation. A motor 2 rotates the roller 1 in the same direction as the arrow, and is mounted on the sewing machine table T so as to be rotatable about a support shaft 2a. A spring 3 biases the motor 2 in the direction of rotation about the support shaft 2a, and one end of the spring 3 is connected to the motor cover 2b, and the other end is connected to the sewing machine table T via the mounting plate 4. Reference numeral 5 denotes a cylinder operated by a drive device (not shown), one end of which is pivoted to the mounting plate 4, and the other end (cylinder rod 2a).
) is pivotally attached to the motor cover 2b,
When inactive, the cylinder rod 5a protrudes and rotates the motor 2 about the support shaft 2a against the force of the spring 3. Reference numeral 6 denotes a swinging member connected to the main shaft of the sewing machine M, which swings in the sewing direction according to the vertical movement of the sewing machine needle N. A clamp C is attached to the lower end of the swinging member.
A pair of feed rollers 7 are provided in pressure contact with the upper surface of the roller. The feed roller 7 is equipped with a one-way clutch mechanism and is rotatable only in the workpiece feeding direction of the swing member 6, so that the clamp C is intermittently fed by the swing of the swing member 6. It's getting old. In this embodiment, the feed roller 7 and the swinging member 6 constitute a clamp feeding means, but the clamp feeding means may include rotating the roller 7 in synchronization with the main shaft by another means such as a motor. , the clamp C may be sent out intermittently. In addition, R ₁ , R ₂ , and R ₃ are reflector plates provided at the starting and ending positions of the curved portion of the clamp C, and these reflector plates R ₁ , R ₂ , and R ₃ are connected to optical sensors ( (not shown).

The operation will now be explained based on the above configuration.

When performing sewing operation, first press clamp C.
Place the clamp guide at the sewing start position of guide groove b.
Cg is inserted, the holding state of the cylinder rod 5a is released, and the motor 2 is rotated around the support shaft 2a by the spring 3 and brought into contact with the side edge of the clamp C. After this, press the start button and the sewing machine M
The main shaft rotates and the sewing machine needle N starts moving up and down, and the swinging member 6 starts swinging in response to the up and down movement of the sewing machine needle N. That is, the swinging member 6 swings in the direction opposite to the feeding direction of the clamp C when the sewing machine needle N descends, and swings in the direction in which the clamp C is fed when the sewing machine needle N rises. At this time, the feed roller 7 rolls on the clamp C due to the movement of the swinging member 6 in the reverse feed direction, and when the member 6 moves in the feed direction, the feed roller 7 is locked by the clutch mechanism. Push out clamp C. By repeating the above operations, the clamp C is intermittently fed out in the linear direction in response to the vertical movement of the sewing machine needle N. During this time, the clamp rotation roller 1, which is pressed against the side surface of the clamp C, is rotating idly because the clutch mechanism is in an open state.
After that, when the bending part Cg ₁ of the guide groove Cg reaches the clamp guide b, the reflection plates R ₁ and R ₂ provided at the bending starting point position of the clamp C are detected by the optical sensor, and the detection signal is As a result, the rotation of the main shaft of the sewing machine M is stopped, and the vertical movement of the sewing machine needle N and the conveyance movement by the roller r are stopped. At the same time, the motor M starts operating, and the clamp rotation roller 1
Rotate in the feeding direction of clamp C,
send out. As a result, the clamp C rotates around the clamp guide b. When the direction of movement of the hands matches the guide groove Cg, the reflector _R3 provided at the bending end position of the clamp C is detected by the optical sensor, and the motor M is stopped based on the detection signal, and the clamp C rotation stops. After this,
Straight stitching is performed again.

As mentioned above, in the case of corner stitching, it is sufficient to operate each roller 1 and 7 at the same time for gentle curve stitching.
In addition, in the case of acute curve sewing, it is sufficient to use the clamp rotating roller 1 as described above.
It can accommodate any sewing pattern.

Further, in this embodiment, the reflector plate R ₁ ,
Place something similar to R ₂ and R ₃ at the sewing start position,
By detecting this, it is possible to automatically move the clamp C from a predetermined position to a sewing start position by driving the motor 2.

In the above embodiment, it was assumed that the detection of whether or not the bent portion Cg ₁ of the guide groove Cg reached the clamp guide b was performed optically, but the reflection plate R ₁ ,
Instead of R ₂ and R ₃ , a magnetic material may be attached to the clamp C for magnetic detection.

In addition, it is also possible to control the operation stoppage of the clamp rotation roller 1 and the feed roller 7 based on the number of stitches formed.

Further, in the above embodiment, the clamp feeding mechanism is constituted by the feeding roller 7 and the swinging member 7, but it is also possible to use other feeding mechanisms, such as well-known feeding teeth.

[Effects of the invention] As explained above, this invention has the effect that appropriate feed can be realized for all sewing patterns such as straight stitches, curved stitches, and corner stitches.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing an embodiment of this invention;
FIG. 2 is a perspective view showing a conventional workpiece feeding device. 1... Clamp rotation roller, {6... Swing member, 7... Feed roller} feed mechanism, C... Clamp, Cg... Guide groove, 2... Motor.

Claims (1)

[Scope of claim for utility model registration] A clamp guide that is fixed over a needle hole formed in the throat plate of a sewing machine and has a needle hole through which the sewing machine needle is inserted, and a guide groove that fits into the clamp guide and has a bent part. It has a clamp that is made up of two plates that have formed a shape and holds a workpiece between the plates, a feed mechanism that intermittently feeds the clamp in a linear direction in accordance with the vertical movement of the sewing machine needle, and a one-way clutch, and is driven by a motor. A clamp rotation roller that rotates only in one direction and is always in pressure contact with the side edge of the clamp, and a reflection plate provided on the upper surface of the clamp corresponding to the curve start point and curve end point of the contact curve of the guide groove of the clamp. , an optical sensor installed on the sewing machine frame facing the reflector, which detects the reflected light from the reflector and generates a curved section start point detection signal and a curved section end point detection signal, and a curved section start inspection from the optical sensor. The output signal stops the driving of the sewing machine needle and the feed mechanism and starts the motor, and the rotation of the clamp rotation roller rotates the clamp plate around the clamp guide. A workpiece feeding device characterized in that a sewing machine needle and a feeding mechanism are started and a motor is stopped in response to a section end point detection signal.