JP3308158B2 - Screw hole inspection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a screw hole inspection device.

[0002]

2. Description of the Related Art Conventionally, a large number of screw holes are formed in a processing line for a transmission case for an automobile or the like, and it is necessary to inspect the screw diameter and the screw depth of the screw holes.

[0003]

However, in the prior art, the above-described inspection of a large number of screw holes formed in an inspection object such as a transmission case for an automobile is performed manually by an operator. There is a limit to improvement of inspection efficiency.

An object of the present invention is to realize an improvement in inspection accuracy and an improvement in inspection efficiency in inspecting the quality of a screw diameter and a screw depth of a screw hole formed in an inspection object.

[0005]

According to a first aspect of the present invention, there is provided a screw hole inspection apparatus for inspecting the screw diameter and the screw depth of a screw hole formed in an inspection object, and fixing the inspection object. A multi-joint robot for mounting and removing a test object fixing table and a screw gauge corresponding to a screw hole of the test object, and positioning the screw gauge at a screw hole position of the test object on the test object fixing table; A gage rotating unit that rotates the gage, provided on the articulated robot, sends the screw gauge according to the lead of the screw hole at the same time as the rotation of the gage rotating unit,
A gauge feeder for screwing a screw gauge into the screw hole of the test object, a torque detector for detecting the torque equivalent value of the gauge rotating unit, a feed amount detector for detecting the feed amount of the gauge feeder, and a screw for the test object For holes, appropriate screw diameter
Set the upper and lower limits of the appropriate screwing torque value in advance, and
The upper and lower limits of the appropriate screw depth position corresponding to the
Set the appropriate torque-up value in advance.
In advance, while driving the articulated robot so that the screw gauge is positioned at those screw hole positions according to the data of the screw hole position of the inspection object, the detection results of the torque detector and feed amount detector are obtained, and the screw hole is obtained. The appropriate screw diameter is determined on the condition that the detection result of the torque detector is within the upper and lower limits of the appropriate screwing torque value over the entire length of the screw hole, and the upper and lower limits of the appropriate screw depth position of the screw hole And a control device for judging the appropriateness of the screw depth on condition that the detection result of the torque detector reaches the set torque increase value within the range .

According to a second aspect of the present invention, in the first aspect of the present invention, the articulated robot further comprises:
Using a horizontal articulated robot, a turning device for turning the test object fixing table is provided, and a turning positioning device for positioning the inspection surface of the test object on the test object fixing table to the inspection work surface of the horizontal articulated robot is provided. It is made to become.

According to the first aspect of the present invention, the following operations are provided. The articulated robot is controlled by the control device, and automatically inspects the screw diameter and the screw depth of the screw hole formed in the inspection object, thereby improving the inspection efficiency. Of course, the screw diameter is determined mechanically and electrically depending on whether the screw diameter is at the appropriate screwing torque value over the entire length of the screw hole, and the screw depth is set within the range of the appropriate screw depth position of the screw hole. Whether the torque-up value has been reached or not is mechanically and electrically determined based on whether the torque-up value has been reached, and the inspection accuracy can be improved.

According to the second aspect, the following operations are provided. By attaching the turning device and the turning positioning device to the inspection object fixing table, the inspection surface of the inspection object can be easily positioned on the inspection work surface of the horizontal articulated robot, and the inspection operation by the horizontal articulated robot can be performed. . Thereby, a low-cost horizontal articulated robot can be adopted.

[0009]

FIG. 1 is a front view showing a screw hole inspection apparatus, FIG. 2 is a side view of FIG. 1, and FIG. 3 is a plan view of FIG.

The inspection apparatus 10 includes a screw hole 2 formed on one surface or multiple surfaces of the inspection object 1 (inspection surface 1A).
A, 2B, 2C... Are inspected for the quality of the screw diameter and screw depth.

The inspection apparatus 10 includes a gantry 11, an inspection object fixing table 12, a horizontal articulated robot 13, and a control device 14.

The inspection object fixing table 12 has a work base 12A.
The work piece 12A is provided with a locate pin which is engaged with a positioning hole of the test object 1, and a clamp base 22 fixed to the work base 12A is provided with a toggle clamp 23 so that the test object 1 can be fixed by the clamp 23.

The inspection object fixing base 12 includes a turning device 24 and a turning positioning device 25. The turning device 24 applies an operating force applied to a handle 26 rotatably supported by the gantry 11 to a bevel gear 27A fixed to the handle 26, a bevel gear 27B fixed to a worm shaft 28 supported by the gantry 11, and a worm. A worm 29A fixed to the shaft 28 and a worm wheel 29B fixed to a turning shaft 30 that is supported by the gantry 11 and supports the test object fixing table 12 are transmitted to the test object fixing table 12 so that the test object 1 can be turned. I do. Swivel positioning device 25
The positioning pin 32 with the handle screwed to the nut 31 fixed to the gantry 11 is attached to the side plate 12B of the inspection object fixing table 12.
The inspection surface 1A of the inspection object 1 on the inspection object fixing table 12 is engaged with the positioning collar 33 provided in the
Can be positioned on the inspection work surface. The positioning collar 33 provided on the side plate 12B of the inspection object fixing base 12 is
The number of rotation axes 3 corresponding to the number of inspection surfaces 1A of inspection object 1
The inspection object 1 provided on the inspection object fixing table 12 is provided around the axis 0.
The inspection surface 1A is sequentially indexed to the inspection work surface of the articulated robot 13 to enable positioning.

The articulated robot 13 has a robot base 4
1, a first arm 42A is swingably supported, and a first arm 42A supports a second arm 42B. 43A is a drive motor of the first arm 42A;
B is a drive motor for the second arm 42B. The articulated robot 13 includes a gauge mounting portion (chuck) 44 on the second arm 42B, and the screw holes 2A, 2B, 2C,.
Can be attached to and detached from the gauge mounting portion 44. Then, the articulated robot 13 includes the first arm 42
A, the screw gauge 3 is positioned at the screw hole position of the inspection object 1 on the inspection object fixing table 12 by the swing control of the second arm 42B. The screw gauge 3 for the gauge mounting portion 44
The attachment and detachment can be optimally performed by an automatic exchange device, or can be performed manually.

The articulated robot 13 includes a second arm 42B.
A gage feed motor (air cylinder) 45 is fixed to the gage feed motor 45, and a gage rotation motor (AC servo motor) 4 is mounted on a lift 46 connected to a piston rod of the gage feed motor 45.
7 is fixed, and the above-mentioned gauge mounting portion 44 is provided on the output shaft of the motor 47. That is, the motor 47 rotates the screw gauge 3. The gauge feed motor 45 is a motor 4
7 and simultaneously rotate the screw gauge 3 into the screw holes 2A, 2B, 2
The screw gauge 3 is screwed into the screw holes 2A, 2B, 2C,... Of the inspection object 1 in accordance with the lead C. The gauge feed motor 45 and the gauge rotation motor 47
Are driven by the control device 14 in association with each other so as to conform to the leads of the screw holes 2A, 2B, 2C,...
Can be increased.

The articulated robot 13 has a torque detector 48 for detecting the torque of the gauge rotation motor 47. The torque detector 48 includes, for example, a current detector that detects the current value of the motor 47.

The articulated robot 13 has a feed amount detector 49 for detecting the feed amount of the gauge feed motor 45. The feed amount detector 49 is composed of, for example, a linear encoder that detects the amount of movement of the guide rod 50 of the lift 46.

The control device 14 is provided with data of the screw hole positions of the inspection object 1 in the memory, and drives the drive motor of the articulated robot 13 so as to position the screw gauge 3 at those screw hole positions in accordance with the data. Drive control is performed on 43A and 43B.

The control device 14 includes a torque detector 48 and a feed amount detector 49 for each screw hole (for example, 2 A) of the inspection object 1.
The following (a) and (b) are performed by obtaining the detection result of (a) Screw Diameter The detection result of the torque detector 48 (the current value of the gauge rotating motor 47) extends over the entire length of the screw hole 2A, and is appropriately set in the control device 14 for the screw hole 2A in advance. The appropriateness of the screw diameter of the screw hole 2A is determined on condition that the torque value is within the range Ta ± ΔT (for example, the current value Ia ± ΔI).

(B) Screw Depth From the detection result of the feed amount detector 49, it was confirmed that the screw gauge 3 was within the range da ± Δd of the appropriate screw depth position of the screw hole 2A set in the controller 14 in advance. Sometimes, the detection result of the torque detector 48 (the current value of the gauge rotating motor 47) is a set torque up value Tb (for example, the current value Ib) preset in the control device 14 for the screw hole 2A.
It is determined that the screw depth of the screw hole 2A is appropriate on condition that the screw hole 2A has been reached (or exceeded).

Hereinafter, the inspection procedure of the inspection apparatus 10 will be described. (1) The data of the screw hole position of the inspection object 1 is set in the memory of the control device 14. This means, for example, that a model of the inspection object 1 is fixed to the inspection object fixing table 12, and a screw gauge 3 provided on the articulated robot 13 is screwed on each of the inspection surfaces 1A of the model with screw holes 2A, 2B of each inspection surface 1A. Drive the articulated robot 13 to position each of
At this time, the positions of the screw holes are taught to the memory of the control device 14.

Note that, based on the production data of the inspection object 1, the inspection object 1
May be set in the memory of the control device 14.

(2) The inspection object 1 to be inspected is fixed to the inspection object fixing table 12, and the turning device 24 and the turning positioning device 25
Is used to sequentially position each inspection surface 1A of the inspection object 1 on the inspection work surface of the articulated robot 13, and the following (3) and (4) are performed.

(3) The articulated robot 1 by the control device 14
3, the screw gauge 3 provided on the articulated robot 13 is screwed into the screw holes 2A, 2B, 2C on the inspection surface 1A of the inspection object 1.
, And screw gauges 3 into their screw holes 2
A, 2B, 2C ...

(4) In the above (3), the torque detector 48
And the detection result of the feed amount detector 49, the above (a), (b)
Of the screw diameter and screw depth of the above.

(5) The inspection result of the above (4) (the screw hole number and its quality) is displayed on the display unit 15 of the control device 14. This inspection result can be printed out by a printer or output to another personal computer.

The inspection device 10 may be provided with a marking device for marking a defect around the defective screw hole of the inspection object 1 based on the inspection result of (4).

The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to this embodiment, and the design can be changed within a range not departing from the gist of the present invention. The present invention is also included in the present invention. For example, the articulated robot 13 is not a horizontal articulated robot, and the screw holes of a plurality of inspection surfaces 1A of the inspection object 1 that are orthogonal to each other without changing the posture of the inspection object 1 fixed to the inspection object fixing table 12. May be an articulated robot capable of screwing the screw gauge 3 to the robot. According to this, when positioning each of the plurality of inspection surfaces 1 </ b> A of the inspection object 1 on the inspection work surface of the articulated robot 13, it is not necessary to turn the inspection object fixing table 12, and the inspection object fixing table 12 uses the turning device 24. ,
It is not necessary to provide the turning positioning device 25.

[0029]

As described above, according to the present invention, when inspecting the quality of the screw diameter and the screw depth of the screw hole formed in the inspection object, the inspection accuracy is improved and the inspection efficiency is improved. can do.

[Brief description of the drawings]

FIG. 1 is a front view showing a screw hole inspection device.

FIG. 2 is a side view of FIG. 1;

FIG. 3 is a plan view of FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Inspection object 1A Inspection surface 2A, 2B, 2C ... Screw hole 3 Screw gauge 10 Inspection device 12 Inspection object fixing stand 13 Articulated robot 14 Control device 24 Swivel device 25 Swivel positioning device 45 Gauge feed motor (Gauge feed unit) 47 Gauge rotation Motor (gauge rotating part) 48 Torque detector 49 Feed amount detector

Claims (2)

(57) [Claims] 1. A screw hole inspection apparatus for inspecting a screw hole and a screw depth of a screw hole formed in an inspection object, the inspection object fixing table for fixing the inspection object, and a screw hole of the inspection object. A multi-joint robot that attaches and detaches a screw gauge to be mounted and positions the screw gauge at the screw hole position of the inspection object on the inspection object fixing table; A gauge feeder for feeding the screw gauge according to the lead of the screw hole at the same time as the rotation of the gauge rotating part and screwing the screw gauge into the screw hole of the inspection object; a torque detector for detecting a torque equivalent value of the gauge rotating part; A feed amount detector that detects the feed amount of the gauge feed unit, and a screw hole of the inspection object that is appropriate for the appropriate screw diameter
Set the upper and lower limits of the screwing torque value in advance, and set the appropriate screw depth.
The upper and lower limits of the appropriate screw depth position corresponding to the
And set an appropriate torque-up value in advance.
In addition to driving the articulated robot so that the screw gauge is positioned at those screw hole positions according to the data of the screw hole positions of the inspection object, the detection results of the torque detector and feed amount detector are obtained, The appropriate screw diameter is determined on the condition that the detection result of the torque detector is within the upper and lower limits of the appropriate screwing torque value over the entire length, and the upper and lower limits of the appropriate screw depth position of the screw hole are determined . A screw hole inspection device, comprising: a control device that determines an appropriate screw depth on condition that a detection result of a torque detector reaches a set torque increase value within a range . 2. A horizontal articulated robot, wherein a horizontal articulated robot is used as the articulated robot, and a turning device for turning the inspection object fixing table is provided. 2. The screw hole inspection device according to claim 1, further comprising a turning positioning device for positioning the screw hole on the inspection work surface.