JPS6016343A - Device for checking or calibrating load sensor in operational apparatus - Google Patents

Abstract

PURPOSE:To enable the characteristic change in a load detector provided at the support head side to be automatically checked by providing a means for checking the characteristic change in a load sensor from the relationship between a displacement amount and the output of the load sensor. CONSTITUTION:A support head 10 to which various types of operative heads 11 can be selectively attached is supportably guided vertically to a cross slide rest 14 by a pair of pilot bars 13a, 13b. Next, a position detector for detecting the rotational amount of a rotary shaft is provided to generate positive or negative pulses in response to the direction of displacement every time an operational section of the operative head 11 such as clamp claw is displaced by a certain distance. The pulse generated from the position detector is supplied to a position detecting counter 45 in a numerical control unit 60 to be accumulated for detecting a position of the operational section of the head 11. Thus, the characteristic change in the load detector can be automatically checked.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a device for checking or calibrating a load sensor in a working device, and in particular to a device for checking or calibrating a load sensor in a working device, and in particular for a working device that is selectively attached to a supporting head. A driving source for the operating section provided on the supporting head side is connected by mounting the working head, and an operating reaction force acting on the operating section is detected in a driving force transmission path on the supporting head side. This invention relates to a device for checking or calibrating a load sensor in a working device equipped with a load sensor.

<Prior art> In general, in such working devices, the output of a load sensor installed on the support head side is used to perform controls according to the work head, such as confirmation of gripping of the article and control of gripping force. If the characteristics change or break down, gripping control etc. cannot be performed accurately.

However, in conventional work devices, such changes in the characteristics of the load sensor cannot be automatically detected, and there is a risk that inaccurate work may be performed due to changes in the characteristics of the load sensor.

<Objective of the Invention> Therefore, an object of the present invention is to enable automatic detection of checking and calibration of a load sensor provided on the support head side in a working head replaceable working device.

<Configuration of the Invention> FIG. 1 is an overall configuration diagram for clearly explaining the present invention. The support head 10 and the work head 11 include the work head 1
1 to the support head 10, a mechanism is provided for linking the operation section 12 of the work head 11 and the drive source on the work side 11, and
A load sensor 37 is provided in the middle of the power transmission path on the support head 10 side.

This support head 10 is equipped with a reference force generating means 58! 50 is attached, the reference force generating means 58 in the mask unit and the drive source SMU are connected, and in this state, the control means 1 is enabled and the load sensor 37
The drive source SMU is energized until a constant load is applied to the drive source SMU.

After this, the check calibration means 2 performs the load sensor 3
7 is detected, and it is determined whether or not it is out of a certain range. If it is out of range, for example, an abnormal signal ABN is output, and if it is not out of range, the detected output value and the reference value are output. Calibration processing is performed to calculate the deviation between the two and store it as a correction value.

<Example> Embodiments of the present invention will be described below based on the drawings.

In FIG. 2, reference numeral 10 denotes a support head on which various types of work heads 11 can be selectively mounted. It is guided and supported and is moved by a servo motor 16 via a feed screw 15. Further, a cross beam 21 is disposed astride a work table 20 that is movably guided on the gutter 18 in a direction perpendicular to the plane of the paper and is moved by a servo motor 19, and the cross beam 21 is moved by the cross beam 21. It is guided movably on the cross beam 21 and can be positioned by a servo motor 22 installed at the end of the cross beam 21. Further, at the left end of the cross beam 21, there is a work head storage magazine 23 for storing a plurality of work heads 11 and a master unit 50.
A head exchange device 24 equipped with an exchange arm is provided, and when the transverse feed table 14 is moved to the left end, the work head I''11 in the hand storage magazine 23 or the mask unit 50 and the work head on the support head IO are installed. 11 or Master Unino) 5 (It is designed to be exchanged with +.

Of the work heads 11, the work head for gripping and transferring articles has a shank portion 11a that fits into a holding hole 10a drilled at the lower end of the support head IO, as shown in FIG. A screw shaft 25 having male threads in opposite directions at both ends is supported at the center of the pawl guide portion 11b integrally formed at the tip of the shank portion 11a.
A pair of gripping claws 12 are screwed into threaded portions at both ends of the threaded shaft 25, extending in a direction perpendicular to the axis of the threaded shaft 25. Further, a drive shaft 27 having an engagement piece 26 at the upper end is supported on the axis of the shank portion 11.2, and this drive shaft 27 and a screw shaft 25
are connected by two pairs of bevel gears 28a and 28b.

On the other hand, the lower end cylindrical part of the support head 10 has a throat 11 for operation.
A notch mechanism 35 is provided to maintain the attached state of the notch 11, and a drive mechanism 36 for rotating the engagement piece 26 of the throat 11 for operation is provided in the upper rectangular portion. This drive mechanism 36 is rotatably mounted on an extension of the axis of the holding hole 10a (=J
The rotary cylinder 40 is connected to the servo motor 38 via the strain-generating cylinder 43, and extends vertically through the axis of the rotary cylinder 40, and is connected to the rotary cylinder 40 by spline engagement. It is composed of a rotating shaft 41 that is allowed to move only in the vertical direction, and a spring 42 that applies a downward pressing force to the rotation 11id+ 41. An engagement tooth formed at one end of the engagement piece 26 is adapted to engage with an engagement tooth of the engagement piece 26.

Then, on the outer periphery of the strain tij 43, a load sensor 37 composed of a semiconductor strain gauge or the like is installed.
The output of the load sensor 37 is the slip ring mechanism, mechanism 44.
It is designed so that it is output to the support and to the 7th and 10th sides via.

4, 9, f; 15 'e';' 38 (7) Upper & iil D is equipped with a position detector 39 for detecting the amount of rotation of the rotating shaft 41. is an incremental type position detector, which generates a positive or negative pulse depending on the direction of displacement each time the operating part of the workpiece 11, such as the gripping claw 12, is displaced by a certain distance, and the pulse is output from this position detector 39. The pulses are controlled by a numerical control device 6, which will be described later.
The signal is supplied to a position detection counter 45 within 0 and is cumulatively added, so that the position of the operating section of the work head 11 can be detected.

Further, the output of the load sensor 37 is transmitted to the numerical control device 60.
The signal is supplied to an AD converter 46 inside the device and converted into a digital quantity.

FIG. 4 shows an example of a mask unit 50 built into the work head storage magazine 23, in which an engagement member and a mask spring are provided in the work head for gripping articles shown in FIG. be.

Several guide shafts 56 parallel to the screw shaft 55 are provided on one of the pair of claws 52. A mask spring 58 is compressed between the engaging member 57 and the claw 52 to which the guide shaft 56 is attached.

Therefore, this mask unit 50 is attached to the supporting head 10.
With the servo motor SMLJ attached to the claw 52.52
When the gripping claw 52 on the side where the guide shaft 56 is not attached comes into contact with the engaging member 57, when the claw 52 is further closed, the spring constant of the mask spring 58 changes. Accordingly, the load acting on the strain cylinder 43 increases, the amount of strain increases proportionally, and the output of the load sensor 37 changes as shown in FIG.

Next, to explain the control circuit, the central processing unit 61 in the numerical control device 60 is constituted by a microprocessor, and a memory 62, a data input device 63, and ink faces 64a and 64b are connected to this central processing unit 61. , the servo motors 19, 1 are installed on the ink face 64a.
Tribe unit D that drives 6, 38, and 22, respectively.
UY, DLIZ, DUIJ, and DtJX are connected, and the position detection counter 45 and the output of the AD conversion circuit 46 are connected to the interface G4bl.

The memory 62 includes a numerical control data area NCD in which numerical control programs for performing various assembly operations are recorded.
A plurality of sets of numerical control programs corresponding to the types of articles to be worked on are written. Numerical control program [J
As shown in FIG. 5, each of the workpieces receives a hand exchange command H00 for attaching a work head 11 suitable for the workpiece to the master unit 50 before attaching it to the support hem.

MO6 is programmed in the first block N0OI, and when this data is read, the currently installed working head 11 is returned to the working head storage machine 23, and
An operation is performed to attach the master Uniso I.50 to the support head 10.

Then, it is programmed into block N002.
When the program of M51 in C is read out, the central processing unit 61 executes the detector check process shown in FIG.

First of all, a pulse is supplied to the drive unino [I) UU in order to close the claw 52 of the mask unit 50 attached to the support throat 10 by a certain amount from the original position 70), and after that, Read the output value of the load sensor 37 (
71). Then, it is determined whether or not the read value F is within the range of Δ1 to Δ[1, which is the usable limit range.
), if it is not within this range, display the difference '+71 (
73), stop work.

On the other hand, if the read value F is within the range AL-'AH, the deviation ΔF between the read value F and the reference value FO is calculated (74,), and this is used as the correction value. ζRemember 75) and complete the calibration process (76).When performing gripping force control, etc.,
The output value is corrected by the stored correction value Δrs, and accurate operating force can be detected.

The rate of change in the repulsive force of the mask spring with respect to the amount of movement of the pawl 52 after the pawl 52 comes into contact with the engaging portion 57 is relatively small as shown in FIG.
Even if the position of the sensor 2 varies to some extent, a constant force can be generated accurately, and the abnormality of the multilayer sensor 37 can be determined with accuracy.

In addition, in the embodiment mentioned above, a change in characteristics was detected when the output of the load sensor fell outside a predetermined range after the servo motor was rotated by a certain amount.
A:: The output value of the heavy sensor or the amount of rotation of the servo motor when the motor is rotated until it reaches a constant value, or the amount of rotation that deviates from the reference amount by more than the allowable value. Good too.

Further, as shown in FIG. 8, the mask unit 50 includes a rotating shaft 8 equipped with an engaging portion 81 that can engage with the rotating shaft 41.
2 is supported on the unit base 80, and a mask spring 86 is installed between the rack 84 that engages with the ridge 82a formed on the rotating shaft 82 and the gear 7 pin 85 fixed to the unit base.
It is also possible to use a configuration in which

Furthermore, the rotation amount of the servo motor SMU and the cart sensor 37
The cane of the load sensor 37 may be detected based on the relationship between the output changes, and the characteristic change of the load lens 37 may be detected based on the magnitude of this cane.

<Effects of the Invention> As described above, the present invention is provided with a reference force generating means composed of a spring or the like, and by being attached to the support and the throat, the first stage of reference force generation transmits the driving force of the throat measurement to the support. a master 1-knit connected to the path; a mounting means for mounting the mask unit on the support head; and a drive source for causing the drive source to act until a specific load is applied to the multilayer sensor by the reference force generating means. a control means, which operates after the drive source control means is activated, and checks or calibrates changes in the characteristics of the load from the relationship between the displacement caused by the drive source and the output of the load sensor; Since the configuration is equipped with a means and means, it is possible to automatically check for changes in the characteristics of the heavy detector or to automatically check the change in the characteristics of the heavy detector. This has the advantage of significantly improving reliability.

[Brief explanation of the drawing]

Figure 1 is an overall configuration diagram of the device that clearly demonstrates the present invention, and Figures 2-
Figure 3 shows an embodiment of the present invention; Figure 2 is a general configuration diagram of the working device with a control circuit not shown and a control circuit diagram; Figure 3 is similar to Figure 2; [Jru support]-1 ＼ Attachment 10 and the structure of the work head I''If'
FIG. 5 is a partially enlarged view showing the configuration of the numerical control data area NCDA in FIG. A flow chart showing the operation of the control device 60, FIG. 7 shows the claw 52.
FIG. 8 is a cross-sectional view showing a modification of the mask unit 50. 10...Support head, 11...Working head, 12.
... Gripping claw, 37... Load sensor, 50... Mask unit, 58.86... Mask splinter, 60.
... Numerical control unit, 61... Central processing unit, 62...
·memory. Patent applicant Toyota Machinery Co., Ltd. Figure 4 41 57565δ

Claims (1)

[Claims] (1) The support 1 is also connected to the operation part of the work head that is selectively attached to the head and the operation part drive source provided on the supporting head side, and the support The working device is equipped with a load sensor that detects the operation reaction force acting on the operation section in the driving force transmission path on the side of the head, and includes a reference force generating means made of a spring or the like, and is attached to the support head to A kudzu master unit in which a reference force generation means is linked to the driving force transmission path on the support head side, a mounting means for attaching this mask unit to the support head, and a specific load applied to the load sensor by the reference force generation means. drive source control means that operates the drive source until the drive source is actuated; and drive source control means that operates after the drive source control means is activated and changes the characteristics of the load sensor based on the relationship between the amount of displacement applied by the drive source and the output of the load sensor. 1. A device for checking or calibrating a load sensor in a working device, comprising means for checking or calibrating a load sensor in a working device.