JP2012000768A - Workpiece identification apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an identification apparatus and an identification method for identifying, without error, various types of workpieces to be charged into a conveyor.SOLUTION: The identification apparatus includes: a measurement unit (8A) which measures the distance to a surface of a workpiece (4A); a transfer unit (10A) which transfers the measurement unit (8A) in the longitudinal direction of the workpiece (4A); and a control unit (14A) which controls the units. An embossed character (22A) for determining the type is printed in a predetermined region of the workpiece (4A). The control unit (14A) has a control function: of obtaining the distance to the surface of the workpiece (4A) while transferring the measurement unit (8A) by means of the transfer unit (10A); and of determining the presence/absence, position, and shape of the projection of the embossed character (22A) in the predetermined region of the workpiece (4A) by means of the measurement unit (8A) and checking specifications, thus determining the type and specifications of the workpiece (4A).

Description

  The present invention relates to an identification device for identifying a workpiece conveyed on a conveyor. More specifically, the present invention relates to an identification device for identifying a workpiece for each specification (or type) when a plurality of types of workpieces having different specifications are mixed and conveyed on a conveyor.

In recent years, customer requests for product specifications have been diversified, and in order to meet diversified demands, there are an increasing number of cases in which product specifications differ for each product destination. At the same time, new models have been added to meet the needs of users, and the number of product types is increasing.
For this reason, it is necessary to remodel conventional equipment that has been used for small-quantity and high-volume production, and to manufacture small-quantity and high-variety models without reducing the operating rate (for multi-variety small-volume manufacturing).

When manufacturing various types of products mixed with conventional equipment (lines), there are various problems, but the biggest problem is that it is possible to judge multiple types of workpieces flowing through the lines (for example, assembly lines) without error. Thus, the assembly work different for each product type is definitely executed.
In the conventional line suitable for low-volume and high-volume production, it was possible to identify the type of product by the shape of the workpiece. However, in the case of high-mix low-volume production, the product is identified only by the shape of the workpiece. Is difficult to do.

For example, a system as shown in FIG. 7 is used for conventional workpiece identification.
The prior art shown in FIG. 7 includes a shaft J having the Docs Da and Db, a proximity sensor Sa that detects the Doc Da, and a proximity sensor Sb that detects the Doc Db. The shaft J is urged in a direction away from the workpiece W by the elastic member Re.
When identifying the workpiece W, the shaft J is moved to the workpiece W side by means not shown.
An area for identification is provided in the workpiece W, and a blind hole B is perforated or not perforated in the area for identification corresponding to the type of the workpiece W.

In FIG. 7, if the blind hole B is drilled in the identification area of the workpiece W, the shaft J moved to the workpiece W by means not shown is inserted into the blind hole B. When the shaft J is inserted into the blind hole B, the proximity sensor Sa detects the approach of the dog Da. On the other hand, when the blind hole B is not perforated in the identification area of the workpiece W, the shaft J contacts the side surface Bs of the workpiece W. If the shaft J abuts on the side surface Bs of the workpiece W and is not inserted into the workpiece W, the proximity sensor Sb detects the approach of the dog Db.
In other words, when the shaft J is inserted into the blind hole B, the dog Da is close to the proximity sensor Sa, but the dog Db is not close to the proximity sensor Sb, and the shaft J is the side surface Bs of the workpiece W. If the dog Db is not inserted into the blind hole B, the dog Db approaches the proximity sensor Sb, but the dog Da does not approach the proximity sensor Sa so that the dogs Da and Db and the proximity sensors Sa and Sb A relative positional relationship is set.

In the region for identifying the workpiece W, a maximum of n blind holes B can be drilled at an appropriate distance in a direction perpendicular to the paper surface in FIG. Although not explicitly shown in FIG. 7, the combination of the shaft J and the proximity sensors Sa and Sb corresponds to n positions of the blind holes B in the direction perpendicular to the paper surface in FIG. A set is provided.
In each of the pierceable location of a blind hole B present n points, it is possible to by such embodiments described above blind hole B to determine whether or not perforated, in the example of FIG. 7, 2 ⁿ kinds of work Can be identified.

However, when such a conventional method is applied, the workpiece cannot be identified in the case shown in FIG.
FIG. 8 schematically shows an example in which different models A and B continuously flow on the conveyor C. The model A has an identification part H1 on the side surface. Further, the model B is provided with a determination unit H2 on the side surface. In the example of FIG. 8, the distance L1 between the discrimination sensor S1 and the discrimination unit H1 is much larger than the distance L2 between the discrimination sensor S1 and the discrimination unit H2.
In FIG. 8, the width B1 of the model A and the width B2 of the model B are shown to be approximately the same length, but depending on the type of workpiece, the dimensions (width length) corresponding to the widths B1 and B2 May be significantly different.

When the discrimination system shown in FIG. 7 is used for the conveyor shown in FIG. 8, there is a possibility that the type of workpiece is erroneously recognized due to the difference between the distances L1 and L2 shown in FIG.
That is, in the state shown in FIG. 8, for example, if the difference between the distances L1 and L2 is longer than the depth dimension of the blind hole B in FIG. 7, n shafts J provided in FIG. When urged in the direction, the dog Da does not reach the workpiece A and moves to a position close to the proximity sensor Sa. As a result, since all the proximity sensors Sa sense the proximity of the dog Da, the workpiece A is “a workpiece of the type in which all the blind holes B are drilled” regardless of whether or not the blind holes B are actually drilled. It will be judged.

In order to cope with such a situation, in the identification system of FIG. 7, the position of the side surface Bs of the workpiece W in the conveyor width direction (the position in the lateral direction in FIG. 7: the direction orthogonal to the arrow Y in FIG. Position) must be constant. In the conventional line, this is dealt with by using a locate pin.
Also in FIG. 8, in order to arrange the workpieces A and B at predetermined positions in the direction orthogonal to the arrow Y, it is necessary to restrict by the locate pin, and it is necessary to attach a locate device to the conventional conveyor C. However, it is impractical to add a set of facilities for regulating by locating pins due to the expansion of the apparatus and the increase in costs. That is, it is difficult to apply the identification system of FIG. 7 to a conventional conveyor.

  As a production system management apparatus according to the prior art, a technique capable of calculating a time during which a defective product stays in a correction line is disclosed (see Patent Document 1). However, this technique does not solve the problem of identifying, without error, a variety of workpieces to be input in an existing line.

JP-A-5-169336

  The present invention addresses the above-described problems, and an object of the present invention is to provide an identification device for identifying various types of workpieces to be loaded on a conveyor without error.

  According to the present invention, in the identification device for identifying the type / specification of the workpiece (for example, the connecting rod of the engine) 4A by positioning the workpieces 4A having a plurality of specifications conveyed on the conveyor 2A at a predetermined position by the positioning device 26, The identification device includes a measuring device (displacement type laser sensor) 8A that measures the distance to the surface of the workpiece 4A, a moving device (cylinder) 10A that moves the measuring device 8A in the longitudinal direction of the workpiece 4A, and a display unit 15 And a control device 14A for controlling the measuring device 8A and the moving device 10A. The workpiece 4A is printed with a raised character 22A for determining the type in a predetermined area. The control device 14A The workpiece 4A is positioned by the positioning device 26 (step S21), and the measuring device 8A is moved by the moving device 10A. The distance to the surface is measured while moving in parallel with the conveying direction (step S22), and the presence or absence of the raised character 22A and the position and shape thereof are specified from the quantitatively measured output waveform 15a (step S23). If it is correct by comparing with the specification of the workpiece 4A, the workpiece is transferred to the next process (step S24).

The effects of the present invention described above are listed below.
(1) Position the workpiece conveyed on the conveyor with the positioning device, measure the distance to the workpiece surface while moving the measuring device (displacement type laser sensor), ) And the position are specified, so there is no wrong assembly due to the difference between the front and back and the specification, which was a conventional problem.
(2) Since the workpiece specifications are determined by the raised parts (engraved characters) on the workpiece surface, the measurement device (displacement type laser sensor) can be identified with high accuracy so that there is no erroneous assembly due to the difference in specifications.

The side view which shows one Embodiment of this invention. The front view of the workpiece | work (connecting rod) thrown into FIG. The side view of FIG. The figure which shows the method of detecting the protrusion character of a workpiece | work with a displacement type laser sensor. Explanatory drawing which shows the detection result of FIG. The flowchart which shows control of one Embodiment of this invention. Explanatory drawing which shows an example of the conventional workpiece | work discrimination | determination system typically. The top view explaining the state from which a different model mixes and flows into a conveyor.

Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a side view showing a configuration of an embodiment of the present invention, and FIGS. 2 and 3 are front and side views of a workpiece 4A.
In FIG. 1, a work 4A (for example, a connecting rod of an engine) is placed on a roller conveyor 2A. The roller conveyor 2A is placed on a table (not shown).

  A box-shaped frame 5A is installed on the floor so as to surround the conveyor 2A and the workpiece 4A around the position where the workpiece 4A stops (the central portion in FIG. 1).

A flat support member 25 is provided on the top 5Aa of the frame 5A.
A positioning device 26 for fixing the workpiece 4A at a predetermined position is attached to the lower left of the support member 25.

The positioning device 26 includes a support member 27 fixed below the support member 25, a cylinder 6 </ b> A, and a positioning member 28.
The cylinder 6 </ b> A is attached to the lower part of the support member 27. The cylinder 6A operates in parallel with the conveying direction of the workpiece 4A.
The positioning member 28 is attached to the cylinder 6A. The positioning member 28 is configured to be able to fix a predetermined position of the workpiece 4A (in the illustrated example, the connecting rod portion 30 on the small end portion 32 side of the connecting rod: see FIG. 2).

A support member 29 is attached to the lower right side of the support member 25. A cylinder (moving device) 10 </ b> A is attached to the lower portion of the support member 29. The cylinder 10A operates in parallel with the conveyance direction of the workpiece 4A.
A displacement type laser sensor (measuring device) 8A is attached to the cylinder 10A via a support member 11 suspended downward.

  The displacement type laser sensor 8A is configured to irradiate a detection light beam E downward from a light projecting unit (not shown) and receive reflected light R by a light receiving unit (not shown).

The connecting rod 4A shown in FIGS. 2 and 3 has a shape that is difficult to distinguish at a glance. In addition, the distance Lc between the large end portion 31 and the small end portion 32 may be different, and this is a component that requires correct type discrimination.
In order to correctly determine the type, a protruding character 22A is printed at the center in the width direction of the connecting rod 30 to determine the front and back of the connecting rod 4A and the model specifications. The raised characters 22A are engraved characters and are protrusions.
In the example of FIGS. 2 and 3, the character 22A has a width × length of 5 mm and a height of 0.5 mm.

In FIG. 1, a display unit 15 such as a display is connected to the displacement laser sensor 8A via a signal line L15. In FIG. 1, a curve 15 a in the display unit 15 indicates the raised height of the stamped character 22, and a straight line 15 b indicates a threshold for determining the presence or absence of the stamped character 22.
A control device 14 </ b> A is connected to the display unit 15. The control unit 14A compares the model specification data from the upstream manufacturing department with the output of the displacement laser sensor 8A to determine the model.

4 and 5 schematically show a state in which the marking character 22A on the connecting rod 4A is discriminated using the displacement type laser sensor 8A. In FIG. 4, engraved characters 22A are raised at a predetermined height on the connecting rod 4A conveyed to the conveyor 2A. A displacement type laser sensor 8A is arranged above the connecting rod 4A.
The displacement laser sensor 8A is moved above the connecting rod 4A by the cylinder 10A on the upper surface of the connecting rod 4A in parallel with the conveying direction of the connecting rod 4A. Then, the presence / absence and contents of the stamped character 22A are determined by the detection light E and the reflected light R.

  FIG. 5 shows the waveform of the output signal of the displacement laser sensor 8A that receives the reflected light R. The waveform is displayed on the display unit 15. The height 13h at the apex 13t of the output signal waveform corresponds to the raised height of the stamped character 22A. In the illustrated embodiment, the embossed height of the stamped character 22A is 0.5 mm.

FIG. 6 is a flowchart showing the control in identifying the connecting rod 4A with the above configuration.
Hereinafter, description will be made with reference to FIGS. 1 to 5 mainly with reference to FIG.
The connecting rod 4A (workpiece) conveyed by the roller conveyor 2A is positioned by the positioning device 26. That is, the cylinder 6 </ b> A fixed to the support member 27 moves the positioning member 28. Then, the connecting rod 30 on the small end 32 side of the connecting rod 4A is stopped and positioned at a predetermined position (step S21).

Next, the connecting rod 4A is measured by the displacement type laser sensor 8A. That is, by operating the cylinder 10A and moving the displacement laser sensor 8A in a direction parallel to the traveling direction of the conveyor 2A, the stamped character 22A to be on the connecting rod portion 22A (see FIGS. 2 to 4) of the connecting rod 4A. Is measured (step S22).
That is, the light beam E emitted from the displacement type laser sensor 8A is applied to the portion where the engraved character 22A is formed, the reflected light R is received by the displacement type laser sensor 8A, and the output waveform 15a is displayed on the display unit 15. (Refer to the display waveform in FIG. 1 and the waveform in FIG. 5).

Next, the waveform 15a is quantitatively measured. That is, the height 13h and shape of the waveform 13 of the embossed character 22A displayed on the waveform display board 15 are measured (see FIG. 5) (step S23).
Then, it is determined whether or not the waveform 15a corresponds to any one of the stamped characters 22A (step S24). In other words, based on the output waveform 15a, the presence / absence of a raised portion and its position and shape are specified.

If it does not correspond to any of the raised characters 22A (step S24 is no), for example, it is determined that the front or back is wrong or the part has different specifications, and is treated as NG and excluded from the work on the conveyor 2A (step S26) ).
If it corresponds to any of the embossed characters 22A (step S24 is yes), it is determined that the connecting rod is a target of work on the conveyor 2A, and is assembled on the conveyor 2A (step S25).

  According to the present invention, the mistake of the front and back of the connecting rod is eliminated, and the mistake of assembling products with different specifications is avoided.

  The illustrated embodiment is merely an example, and does not limit the technical scope of the present invention.

2A ... Conveyor 4A ... Work 5A ... Frame 6A ... Cylinder 8A ... Displacement laser sensor (measuring device)
10A ... Cylinder (moving device)
14A... Control device 22A... Engraved character (raised portion), raised character 26.

Claims (1)

  In the identification device for identifying the type and specification of the workpiece (4A) by positioning the workpiece (4A) having a plurality of specifications conveyed on the conveyor (2A) at a predetermined position by the positioning device (26), the identification device includes: The measuring device (8A) that measures the distance to the surface of (4A), the moving device (10A) that moves the measuring device (8A) in the longitudinal direction of the workpiece (4A), and the display unit (15) are connected. A control device (14A) for controlling the measuring device (8A) and the moving device (10A), and the workpiece (4A) is printed with a raised character (22A) for identifying the type in a predetermined area. The control device (14A) positions the workpiece (4A) with the positioning device (26), and the measuring device (8A) with the moving device (10A) in parallel with the conveying direction of the workpiece (4A). Measure the distance to the surface while moving, specify the presence or absence of the raised character (22A) from the quantitatively measured output waveform (15a), its position and shape, and collate with the workpiece (4A) specifications If it is correct, it has a control function of conveying to the next process.

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