JPH04348792A - Guide roller device for sewing machine - Google Patents

Abstract

PURPOSE:To guarantee the proper feeding of an object to be sewn by providing a detecting means to detect the step part of the object to be sewn in front of the feeding direction of a roller body positioning at the back of sewing machine presser metal in the advancing direction of sewing and slightly moving the roller body upward when the step part is detected. CONSTITUTION:When the step part of the object to be sewn arrives at a detection roller 8 in the case of sewing and the detection roller 8 tries to get over the step part to change the position, a supporting arm 9 is oscillated and a non-contact displacement sensor 7 is operated in counter to an upper face 9a of the supporting arm 9. According to the output of this sensor 7, the drive of an actuator 6 at a moving means C is controlled, and a roller body R is slightly moved upward. Thus, the step part of the object to be sewn can easily go under the roller body R, and the roller body R can properly get over the step part. After getting over the step part, the roller body R is pushed to the object to be sewn by a spring body B, and the feeding of the object to be sewn is supported.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to a cloth pulling roller device for a sewing machine that assists the progress of sewing a workpiece, and more specifically, the present invention relates to a cloth-pulling roller device for a sewing machine that assists the sewing progress of a workpiece, and more specifically, a cloth-pulling roller device that properly handles the workpiece without stopping when it engages with a stepped portion of the workpiece. This invention relates to a cloth-pulling roller device for a sewing machine that assists the sewing machine's progress.

0002

2. Description of the Related Art Sewing machines are equipped with a feed dog that comes into contact with the lower surface of the workpiece and feeds the workpiece in order to feed the workpiece as sewing progresses. However, depending on the thickness, material, etc. of the workpiece, the sewing machine may not be able to feed the workpiece an appropriate amount by using only the feed teeth of the sewing machine.

[0003] In order to solve these inconveniences, a cloth-pulling roller device that can be attached to a sewing machine, assists the feed dog of the sewing machine, and feeds the material to be sewn has been proposed. FIG. 3A is a diagram showing a cloth-pulling roller device attached to sewing machine M. In the figure, R denotes a roller body, and this roller body R is located behind the presser foot 1 of the sewing machine in the traveling direction X of the workpiece W.

Reference numeral 2 denotes a motor that is housed in the machine frame 2a and is connected to the roller body R, and is capable of rotating the roller body R (clockwise in the figure) in accordance with the progress of the workpiece W. It looks like this. Further, 3 is a vertical bar whose lower end is fixed to the machine frame 2a and is supported by the sewing machine mounting body Ma so as to be able to rise and fall; It is a spring body provided to bias the object W.

The cloth pulling roller configured as described above rotates the roller body R in accordance with the progress of sewing the workpiece W of the sewing machine M, and feeds the workpiece W together with the feed dog 4 provided on the sewing machine M. I can do it.

[0006]

However, the conventional cloth-pulling roller device described above has the following problems. When the stepped portion 5 such as the overlapping portion of the workpiece W as shown in FIG. 4 is particularly large, the roller body R biased downward by the spring body B (see FIG. 3) It may not be able to climb over properly, and the workpiece W cannot be fed.
As shown in FIG. 5, the problem arises that the object W to be sewn is deformed.

[0007] When the sewing object W has stopped being fed, the quality of the sewn product deteriorates due to the repeated formation of seams at the same position, and the sewn portion becomes hardened, resulting in breakage of the sewing needle.

[0008]

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned conventional problems, and includes a cloth-pulling roller device of a sewing machine, which is disposed in front of the roller body in the feeding direction so as to form a part of the step part of the workpiece to be sewn. The present invention attempts to solve the above-mentioned problems of the prior art by comprising a detection means for detecting the detection means, and a moving means for slightly moving the roller body upward in response to a detection signal from the detection means.

[0009]

[Operation] The cloth pulling roller device of the sewing machine according to the present invention has the following features:
A detecting means detects a stepped portion of the object to be sewn, and a moving means slightly raises the roller body to properly move the roller body over the stepped portion.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be explained based on the drawings. Note that the same parts as in the conventional example are denoted by the same reference numerals, and redundant explanation will be omitted. 1 and 2 are diagrams showing an embodiment of a cloth-pulling roller device for a sewing machine according to the present invention.

In the figure, S is a detection means, and this detection means S includes a detection roller 8, a support arm 9 that rotatably supports the detection roller 8, and a non-contact displacement sensor 7 provided above the support arm 9. It is composed of: The detection roller 8 is provided between the roller body R and the presser foot 1 as shown in the figure, and its rotating direction is the same as that of the roller body R.

The support arm 9 is rotatably supported at its center by a shaft pin P and has a spring 10, which urges the detection roller 8 downward (towards the object to be sewn). Further, the non-contact displacement sensor 7 is provided so as to face the upper surface 9a of the support arm 9, as shown in the figure, so that it can detect changes in the position of the support arm 9.

On the other hand, C is a moving means. 6 is an actuator, and this actuator 6 is connected to the non-contact displacement sensor 7, and the non-contact displacement sensor 7 is connected to the support arm 9.
When a change in position is detected, the advancing/retracting portion 6a can be moved upward. Reference numeral 12 denotes a lifting rod, and as shown in FIG. When the advancing/retracting portion 6a is raised, the nut 14 is brought into contact with the inner wall of the machine frame 2a, and the machine frame 2a (
The roller body R) can be raised.

Reference numeral 13 denotes a nut serving as a stopper that is provided on the lifting rod 12 so that its position can be adjusted in the vertical direction. The lifting rod 12 can be raised by a distance corresponding to that distance. In the cloth pulling roller device of the sewing machine configured as described above, when a stepped portion of the object to be sewn reaches the detection roller 8 during sewing, the position of the detection roller 8 (support arm 9) changes due to the stepped portion.

As a result, the non-contact displacement sensor 7 facing the upper surface 9a of the support arm 9 is actuated to drive the actuator 6 of the moving means C, that is, to slightly raise the roller body R to reduce the stepped portion of the workpiece. This makes it easier for the sewing object to get under the roller body R and to properly get over the roller body R. The amount of rise of the roller body R can be adjusted by adjusting the height position of the nut 13, and may be adjusted as appropriate depending on the material of the object to be sewn, the condition of the stepped portion, etc.

When the roller body R has finished climbing over the step, the support arm 9 is stopped, so the non-contact displacement sensor 7 is not activated, and the actuator 6 is also stopped, and the roller The body R is biased against the workpiece by the spring body B, and can feed the workpiece.

[0017]

[Effects of the Invention] As explained above, the cloth pulling roller device for a sewing machine according to the present invention includes a detection means for detecting a stepped portion of a workpiece, and a roller body that moves slightly upward when the detection means detects the step. Because it was configured with a means of transportation,
It is possible to assist the roller body to properly get over the stepped portion of the workpiece, and it becomes possible to appropriately feed the workpiece.

[0018] This prevents deformation of the workpiece by the roller body and the formation of repeated seams at the same location,
It is possible to improve sewing quality and eliminate inconveniences such as damage to sewing needles.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of a cloth-pulling roller device for a sewing machine according to the present invention.

FIG. 2 is a side view of the cloth pulling roller device of the sewing machine shown in FIG. 1;

FIG. 3 is a front view showing a cloth pulling roller device of a conventional sewing machine.

FIG. 4 is a side view showing a stepped portion of the roller body and the workpiece.

FIG. 5 is a side view showing a state in which the roller body of the cloth-pulling roller device of the conventional sewing machine is unable to properly get over the stepped portion of the workpiece, causing the workpiece to be deformed.

[Explanation of symbols]

S Detection means R Roller body 6. Means of transportation 7 Sensor 8 Detection roller

Claims (1)

[Claims] Claim 1: A roller body located behind a sewing machine presser foot in the direction of sewing progress of a workpiece, a motor that rotates the roller body and feeds the workpiece, and a motor that urges the roller body against the workpiece. A cloth pulling roller device for a sewing machine includes a spring body, a detection means disposed in front of the roller body in the feeding direction to detect a stepped portion of the workpiece, and a detection signal from the detection means to move the roller body slightly upward. A cloth-pulling roller device for a sewing machine, comprising: a moving means for moving the cloth-pulling roller device.