JP2693830B2 - Processing method for soft long workpieces - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for processing a flexible and long work that easily expands and contracts. The processing method of the present invention is useful for manufacturing weather strips for automobiles.

[Prior Art] In order to manufacture a weather strip for an automobile, first, extrusion molding is used to form a long work having a constant cross section from sponge rubber. Next, following the extrusion molding, a plurality of clip holes are formed at a plurality of predetermined positions of the work and cut into a predetermined size. After that, a double-sided tape is attached to a predetermined position of each cut work by heat fusion, and a plurality of clips are inserted for each work to obtain a product.

Also, stick the double-sided tape to the extrusion molding,
There is also known a continuous manufacturing method in which a clip hole is formed and a clip is inserted, and then the product is cut into a product (Japanese Patent Publication No. 1-9132, etc.).

By the way, sponge rubber easily expands and contracts, and if the temperature difference is large, the degree of expansion and contraction also increases. Since the former manufacturing method has been cut into a predetermined length and then processed, even if it expands and contracts due to heating in the step of attaching the double-sided tape, the product size is hardly affected. Also, the precision of the position of the double-sided tape and the position of the clip hole is high. However, in the former manufacturing method, it is difficult to automate the transfer of the work between the respective steps, and the number of steps is large. In addition, work stocks are required to smoothly carry out each process, and storage space, management, and the like are indirectly factors that increase costs.

According to the latter manufacturing method, since the processing is continuously performed by extrusion molding, the problems of the former manufacturing method are eliminated, and continuous automatic production is possible. Also, no stock is required.
However, the work is stretched in the step of attaching the double-sided tape, and the precision of the position to which the double-sided tape can be attached becomes low. Even if the attachment position is decided in consideration of the amount of elongation, the error generated there will be added when the double-sided tape is attached to the next part of the work, and the error will be integrated in the snow dharma formula, improving the positioning accuracy. Was difficult. Further, the work expands and contracts even in the process of forming the clip holes, and small errors are accumulated in the same manner, so that the position accuracy is low.

[Problems to be Solved by the Invention] The present invention has been made in view of the above-mentioned circumstances, and it is possible to perform continuous processing continuously after extrusion molding, and substantially the same accuracy as when processing is performed after cutting in advance. The purpose is to secure.

[Means for Solving the Problems] A method for processing a soft long workpiece according to the present invention includes a marking step of marking a soft long workpiece at predetermined intervals larger than a target cutting length, and detecting one mark. A machining process for machining the work between one mark and the next mark behind, and a cutting process for cutting the work at the position of the one mark and at the position separated by the intended cutting length from the one mark to the rear. It is characterized by performing.

The soft long work is not particularly limited as long as it expands and contracts during processing, and rubber, sponge rubber, resin,
It is formed of a material such as a fiber aggregate.

In the marking step, marks are attached to a long work at predetermined intervals larger than the target cutting length. Here, the target cutting length refers to a target cutting length such as the final product length, and the interval between the marks is equal to or more than the length of the target cutting length in consideration of expansion and contraction. There is no longer limit, but if it is too long, loss will increase. The mark may be attached with paint or ink, or may be attached mechanically such as with scratches.

The processing step is not limited as long as it is a step of processing a mark, and various selections such as a step of forming a hole, a step of attaching a tape, a step of assembling other parts can be made. This processing step is performed between two adjacent marks. That is, one mark is detected, and processing is performed within a predetermined length range with that position as the origin. After the processing is completed, the process waits until the next mark is detected. When performing multiple processing steps,
It is desirable to carry out continuously.

In the cutting step, the work is cut at the position of the one mark and at a position separated from the one mark by a target cutting length rearward. As a result, a product that has been processed and cut into the desired cut length is obtained. Since the distance between the two marks is larger than the intended cutting length, some loss may occur unless contraction occurs during processing.

[Operation and Effect of the Invention] In the method of processing a soft long workpiece according to the present invention, the workpiece is first detected and then processed within a predetermined length. Therefore, the tip of the processing position is determined by the unit of the product length by detecting each mark. That is, the position of the mark serves as an origin for determining the machining position, and the machining position is set with this origin as a reference. If the work expands or contracts during processing, set the length to match the expansion. Therefore, since the processing position can be set for each product, error integration does not occur even when a long workpiece is continuously processed, and the position accuracy during processing can be increased.

Then, a cutting process is performed after the processing process is completed. In this case as well, the mark is first detected, and the position of the mark becomes the origin of the unit length for cutting, and the work is cut at the position of the origin and the position rearward from the origin with the target cutting length. Since this origin is the same as the above-mentioned origin for determining the machining position, the precision of the machining position is maintained high even after cutting.

Therefore, according to the processing method of the present invention, it is possible to continuously perform processing and cutting while maintaining high positioning accuracy. As a result, automation is possible, the defective rate is remarkably reduced, the stock is not required, and the cost can be reduced.

[Examples] Hereinafter, specific examples will be described. The present embodiment is an application of the present invention to the manufacture of weather strips for automobiles.

2 and 3 show a cross-sectional view and a perspective view of a main part of a weather strip as a final product. This weather strip is formed of sponge rubber in a long shape having a constant cross section, and double-sided tapes 31 and 41 of a predetermined length are attached to two positions on the side surface. Further, a plurality of clip holes 52 are provided at intervals, and clips 53 are inserted into the clip holes 52.
In this weather strip, accuracy is required for the entire length, the distance from the end surface of the weather strip to the double-sided tape 31, the distance between the clip holes 52, and the like.

(Marking process) Work 1 is conveyed at the same extrusion speed of 1.3 m / min,
The marking device 2 marks the surface. The marking device 2 is adjusted so that the next mark is attached when the work 1 is conveyed by the target cutting length (1900 mm) +10 mm from the position of the attached mark.

(Processing Step) In the first processing step, the double-sided tape 31 is attached to one side surface of the work 1. This process is double sided tape applying machine 3
It is performed by An encoder (not shown) is arranged inside the double-sided tape sticking machine 3, and a first set value corresponding to the tape sticking start position and a second set value corresponding to the tape sticking end position according to the transport distance of the work 1. The value is fixed.

When the work 1 enters the double-sided tape applicator 3 and the marking sensor 30 composed of a reflective photoelectric sensor detects a mark,
The internal encoder reaches the home position and counting starts. At the same time, the work 1 is heated to a predetermined temperature, and when the count of the encoder reaches the first set value, the double-sided tape 31 is supplied and attached to the surface of the work 1 by heat fusion. Then, when the count of the encoder reaches the second set value, the double-faced tape 31 is cut and the attachment is completed. Although the work 1 is expanded and contracted by heating, the encoder first set value and the encoder second set value are set in consideration of the expansion.

In the second processing step, the double-sided tape 41 is attached to the other side surface of the work 1. In addition, double-sided tape applying machine 4
An encoder (not shown) is also arranged inside, and a first set value corresponding to the tape sticking start position and a second set value corresponding to the tape sticking end position are determined according to the transport distance of the work 1.

When the work 1 enters the double-sided tape applicator 4 and the marking sensor 40 consisting of a reflective photoelectric sensor detects a mark,
The internal encoder reaches the home position and counting starts. At the same time, the work 1 is heated to a predetermined temperature, and when the encoder count reaches the first set value, the double-sided tape 41 is supplied and attached to the surface of the work 1 by thermal fusion. When the count of the encoder reaches the second set value, the double-sided tape 41 is cut and the sticking is completed. In this step, the work is expanded and contracted by heating,
Similar to the machining process, the encoder's first set value and second
The set value is set in consideration of the expansion and contraction.

Next, the work 1 is cooled and conveyed to the clip hole punching insert cutting machine 5 which is the third processing step. An encoder (not shown) is also arranged inside the clip hole inserting and cutting machine 5, and a plurality of first setting values and marking sensors 50 corresponding to positions where a plurality of clip holes are to be drilled are provided according to the transport distance of the work 1. The second set value corresponding to the distance between the cutting device 54 and the cutting device 54 and the third set value corresponding to the target cutting length are determined.

When the marking sensor 50, which is a reflective photoelectric sensor, detects a mark, the internal encoder becomes the origin position and counting is started. Then, at the positions where the counts of the encoders have reached the respective first set values, the clip hole punching inserter 51 or the work 1 is provided with the clip holes 52 at intervals, and the clips 53 are inserted into the clip holes 52. When the encoder count reaches the second set value, the cutting device 54
Since the mark has reached the position of, the work 1 is cut at the position of the mark. Further, the work 1 is cut by the cutting device 54 even at the position where the encoder count reaches the third set value.

Although the work 1 slightly expands and contracts in the third machining step, the first set value, the second set value, and the third set value of the encoder are set in consideration of the expansion and contraction.

As described above, according to the processing method of this embodiment, the work 1 can be continuously processed, and full automation can be achieved. Further, since the encoder is used as the origin by detecting the mark, it is possible to position the machining for each product length, and the machining position is stabilized. Since the setting value of the encoder is set in consideration of the degree of expansion and contraction of the work, it is possible to perform accurate machining regardless of the expansion and contraction of the work.

[Brief description of the drawings]

The drawings relate to an embodiment of the present invention. FIG. 1 is a schematic configuration explanatory view of a processing apparatus in each step, FIG. 2 is a sectional view of the obtained weather strip, and FIG. 3 is a main part of the obtained weather strip. It is a perspective view. 1 …… Workpiece, 2 …… Marking device 3,4 …… Double-sided tape applying machine 5 …… Clip hole punching insert cutting machine 30, 40,50 …… Marking sensor 31,41 …… Double-sided tape 52 …… Clip hole, 53 …… Clip

Claims (1)

(57) [Claims] 1. A marking step of marking a soft long work at a predetermined interval larger than a target cutting length, and detecting one of the marks and arranging the mark from the one mark to the next subsequent mark. A flexible long length characterized by performing a processing step of processing a work and a cutting step of cutting the work at the position of the one mark and at a position separated from the one mark by the target cutting length rearward. Processing method for work pieces.