JPH04210343A - Automatic screw inserting machine - Google Patents

Abstract

PURPOSE:To insert a screw correctly without spending a lot of times in the confirmation of a screw hole by equipping a laser spot visual sensor for deciding as to whether or not the screw hole of an object body exists in the inserting objective zone of an automatic screw inserting machine. CONSTITUTION:In the case of a work bench 13 coming to the right in front of an automatic screw inserting machine main body 11, the arm 14 fitted to the main body 11 sets an object body 12 at the specified position. Then, on the picture image subjected to light receiving by a CCD image pick-up element 20 in a laser spot visual sensor 17, the laser beam radiated on a screw hole 16 is not reflected, in the case of the hole 16 existing at the part where the laser beam is radiated by a picture image processing circuit 22, so the output of each picture element of the element 20 becomes a value L. In case of no hole 16 existing, also, the output of each picture element of the element 20 becomes at a value H, so the number of the value H is calculated, and the presence of the screw hole 16 is decided with the accumulating total value being or less than a certain threshold value.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an automatic screw insertion machine used in a factory or the like.

2. Description of the Related Art In recent years, automatic screw insertion machines have rapidly become popular as factory automation increases.

A conventional automatic screw insertion machine will be explained below. FIG. 4 shows a schematic configuration of a conventional automatic screw insertion machine.

In Fig. 4, 1 is the main body of the automatic screw insertion machine, 2 is the target object to which the screw is inserted, 3 is the workbench for moving the target object 2, 4 is the arm that supports the target object 2, and 5 is the target object 2. A screw insertion rod for inserting a screw toward a screw hole, 6 a screw hole existing in the target object 2, and 7 a contact sensor 8 at the tip for determining whether the target object 2 is placed at a predetermined position. It is a rod with a contact sensor.

The operation of the automatic screw insertion machine configured as described above will be explained below.

First, workbenches 3 on which target objects 2 are placed are periodically brought in by an assembly line. When the workbench 3 comes directly in front of the automatic screw insertion machine main body 1, an arm 4 attached to the automatic screw insertion machine main body 1 sets the target object 2 at a predetermined position. Then, the automatic screw insertion machine main body 1 tries to insert a screw into the screw hole 6 existing in the target object 2 through the screw insertion rod 5. At this time, if the target object 2 is not present or is not placed in the correct position with respect to the automatic screw insertion machine main body 1, inserting the screw becomes dangerous and time-consuming. Therefore, in order to determine whether or not the target object 2 is placed in front of the automatic screw insertion machine main body 1 at a predetermined position, a contact sensor rod 7 is protruded from the automatic screw insertion machine main body 1. After confirming the presence or absence of the target object 2 using the contact sensor 8 at the tip, the screw is inserted into the screw hole 6.

Problems to be Solved by the Invention However, in the conventional configuration described above, it takes time to protrude and retract the contact sensor rod 7 in order to confirm the presence or absence of the target object 2, and the work flow is slow. There was a problem with delays. In addition, although the presence of the target object 2 can be determined by the contact sensor rod 7, it cannot be determined whether the screw hole 6 is in the specified position with respect to the automatic screw insertion machine body. There was a risk that it would turn into something.

The present invention solves these conventional problems, and aims to provide an automatic screw insertion machine that can accurately insert screws without spending a lot of time checking screw holes. do.

Means for Solving the Problems In order to achieve the above object, the automatic screw insertion machine of the present invention has a method for determining whether or not a screw hole of a target object exists in the insertion target area of the automatic screw insertion machine. It is equipped with a laser spot visual sensor.

The laser spot visual sensor includes at least a laser main body, a laser drive circuit, a CCD image sensor, an image sensor drive section, an image processing section, and a screw insertion command section.

Effect of the Invention With the above configuration, the present invention can check whether there is a screw hole on a target object and whether it is properly placed or not without contact and in almost no time. Efficiency and quality can be improved.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a schematic configuration of an automatic screw insertion machine according to an embodiment of the present invention. In Fig. 1, 11 is the main body of the automatic screw insertion machine, 12 is the object into which the screw is inserted, 1
3 is a workbench for moving the target object 12; 14 is an arm that supports the target object 12; 15 is a screw insertion rod for inserting a screw toward the screw hole of the target object 12; 16 is a target object 12;
The screw hole 17 present in is a laser spot visual sensor that determines whether the screw hole 16 is placed at a predetermined position.

The operation of the automatic screw insertion machine configured as described above will be explained below.

First, workbenches 13 on which target objects 12 are placed are periodically brought in by an assembly line. When the workbench 13 comes directly in front of the automatic screw insertion machine main body 11, the automatic screw insertion machine main body 1
An arm 14 attached to 1 sets the target object 12 in a predetermined position.

Next, the laser spot visual sensor 17 determines whether the screw hole 16 of the target object 12 is located in the front of the automatic screw insertion machine body 11 and at a predetermined position. When it is determined that the screw hole 16 is located correctly, the screw insertion rod 15 inserts the screw toward the screw hole 16.

FIG. 2 shows the system configuration of a laser spot visual sensor in one embodiment of the present invention.

In FIG. 2, 12 is the target object, 13 is the workbench, and 18
19 is a laser main body that emits a laser beam toward the target object 12; 2o is a CCD image pickup device that receives reflected light from the target object 12; An image sensor drive circuit that drives and controls the CCD image sensor 20, 22 an image processing circuit that checks whether there is a screw hole 16 based on image data captured by the CCD image sensor 20, and 23 whether or not a screw is finally inserted. 24 is a light-shielding window for adjusting the spot diameter of the laser beam.

Next, the operation of the above embodiment will be explained. First, the laser drive circuit 18 applies a voltage to the laser body 19 at regular intervals to emit laser pulses toward the target object 12 . Next, the reflected light reflected by the target object 12 is received by the CCD image sensor 20 . The CCD image sensor 20 is controlled by an image sensor drive circuit 21. The image received by the CCD image sensor 20 is subjected to binary conversion for each pixel by the image processing circuit 22, and if the number of pixels is large, the processing data is reduced by thinning out or the like. That is, if the screw hole 16 exists in the part irradiated with the laser beam, the laser beam irradiated onto the screw hole 16 will not be reflected, so the output of each pixel of the CCD image sensor 20 will be the L value. .

In addition, if the screw hole 16 does not exist, the output of each pixel of the CCD image sensor 20 will be H due to the reflected light from the target object 12.
Therefore, the number of H[ is calculated and the presence or absence of the screw hole 16 is determined based on whether the cumulative value is greater or less than a certain threshold value. The L value may be used instead of the H value. Here, a certain threshold value is a value determined empirically in advance to determine whether the presence or absence of the screw hole 16 is present based on the cumulative number of the H value or L value.

Figure 3 shows an example in which the image data photographed in this way is converted into binary values and further thinned out. (a) shows the case where there are 16 screw holes or no screw holes, and (b) shows the case where there are 16 screw holes. .

In this way, it can be determined with a fairly high degree of accuracy whether or not the screw hole 16 of the target object 12 is in a predetermined position on the front of the automatic screw insertion machine main body 11. If the presence of the screw hole 16 is confirmed, the information is transmitted to the screw insertion machine main body 11 by the screw insertion command circuit 23, and the screw is inserted into the screw hole 16 by the screw insertion rod 15.

On the other hand, since it is necessary to adjust the size of the laser spot to be irradiated depending on the size of the screw hole 16 on the target object 12, the distance between the screw insertion machine main body 11 and the target object 12, etc., the diaphragm aperture diameter can be adjusted. The window 24 is used to change the spot diameter of the laser light that is blocked.

Effects of the Invention As described above, the automatic screw insertion machine according to the present invention is equipped with a laser spot visual sensor for determining whether or not the screw hole of the target object exists in the insertion target area of the automatic screw insertion machine. Therefore, the presence or absence of screw holes can be checked non-contact and in almost no time, preventing incorrect screw insertion and improving work efficiency and quality, making it ideal for use in factory automation. It is possible to realize an automatic screw insertion machine.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an automatic screw insertion machine according to an embodiment of the present invention, FIG. 2 is a system diagram of a laser spot visual sensor according to an embodiment of the present invention, and FIG. 3 is an embodiment of the present invention. FIG. 4 is a schematic diagram of the image data of the conventional automatic screw insertion machine. 11...Automatic screw insertion machine main body, 12...Target object,
13... Workbench, 14... Arm, 15... Screw insertion rod, 16... Screw hole, 17... Laser spot visual sensor, 18... Laser drive circuit, 19... Laser body , 2o... CCD image sensor, 21... Image sensor drive circuit, 22... Image processing circuit, 23... Screw insertion command circuit, 24... Light shielding window. Name of agent Patent attorney Masahiro Kura Go Figure 1 Figure 2 Figure 3 OL value Figure 4

Claims (5)

[Claims] (1) An automatic screw insertion machine equipped with a laser spot visual sensor for determining whether a screw hole of a target object exists in the insertion target area of the automatic screw insertion machine. (2) a laser drive circuit that serves as a laser spot visual sensor and sends a laser emission command and a pause command at regular intervals;
A laser main body that emits laser light toward a target object based on a command from the laser drive circuit, a CCD image sensor that receives reflected light from the target object, and an image sensor drive unit that drives the CCD image sensor. , an image processing unit that checks the presence or absence of a screw hole based on the image data captured by the CCD image sensor, and a screw insertion command that ultimately determines whether or not to insert a screw and notifies the automatic screw insertion machine main body. The automatic screw insertion machine according to claim 1, further comprising a section. (3) The automatic screw insertion machine according to claim (1) or (2), further comprising a light-shielding window for adjusting the spot diameter of the laser beam. (4) As an image processing unit that confirms the presence or absence of screw holes from the image captured by the CCD, there is a circuit that converts the captured image data into binary values, and a circuit that calculates the H value of the converted H value and L value. The automatic screw insertion machine according to any one of claims (1) to (3), further comprising: a determination circuit that determines the presence or absence of a screw hole based on whether the total value of the H values is greater than or less than a threshold value. . (5) As an image processing unit that confirms the presence or absence of screw holes from images captured by the CCD, there is a circuit that converts the captured image data into binary values, and a circuit that calculates the L value of the converted H and L values. The automatic screw insertion machine according to any one of claims 1 to 3, further comprising: a determination circuit that determines the presence or absence of a screw hole based on whether the total value of the L values is greater than or less than a threshold value. .