JPH05123991A - Hand device - Google Patents

Abstract

PURPOSE:To detect the released time of a printed board correctly and change the opening/closing quantity of fingers according to the size of the printed board. CONSTITUTION:In this hand device, feed screw with a right screw 5a and a left screw 5b connected thereto is rotated, and a pair of fingers 6a, 6b are moved to turn a grip detecting sensor 14, provided at one finger 6b, on or off so as to detect the gripping state. At the same time, the rotating quantity of the feed screw 5 is detected by feed screw rotating quantity detecting mechanism 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hand device for gripping and releasing a printed circuit board or the like, and more particularly to detecting the opening / closing amount of fingers.

[0002]

2. Description of the Related Art Conventionally, a hand device for gripping and releasing a printed circuit board or the like turns on a gripping detection sensor provided on one finger by rotating a feed screw connecting right and left screws to move a pair of fingers. Or, it was turned off, and it was detected that the printed circuit board or the like was gripped. Hereinafter, a printed board holding and releasing operation of the conventional hand device will be described with reference to the drawings.

FIG. 3 is a perspective view showing a conventional hand device,
FIG. 4 is a front view showing a conventional hand device, and FIG. 5 is a detailed view showing a part of the conventional hand device. In FIG. 3, the housing 2 forming the outer contour of the hand device 1 is formed in a U-shape including a main body 2a and arms 2b and 2c, and the sensor 3 is attached to the main body 2a. Both arms 2b,
A guide shaft 4 is fixedly provided between 2c, and a feed screw 5 including a right screw 5a and a left screw 5b is rotatably provided in parallel with the guide shaft 4. The fingers 6a and 6b are attached to the guide shaft 4 and the feed screw 5 via bushes 7a and 7b and nuts 8a and 8b, respectively. A gripping block 9a for gripping the printed circuit board is fixedly provided on the finger 6a. On the other hand, as shown in FIG. 5, the grip block 9b integrally formed with the shaft 10 is provided with a snap ring 11 for preventing slipping off at an end portion of the shaft 10 so that the shaft 10 is slidably provided on the finger 6b. A compression spring 12 is interposed between the grip block 9b and the finger 6b. Shaft 10
Slides along the bush 16 press-fitted into the finger 6b. The grip blocks 9a and 9b are provided at positions facing each other. A sensor mounting bracket 13 is fixed to the outer side surface of the finger 6b, and the sensor mounting bracket 13 is provided with a grip detection sensor 14 that detects the end of the shaft 10.

Next, the operation of gripping and releasing the printed circuit board and the finger open / close detection operation of the conventional hand device having this structure will be described.

In FIG. 4, when the fingers 6a and 6b are at the maximum open position, the sensor 3 detects the bush 7b and is in the ON state. On the other hand, the grip detection sensor 14 is
Since there is no load on the compression spring 12, the end of the shaft 10 cannot be detected, and the compression spring 12 is in the off state. When the feed screw 5 is rotated in the normal direction by a small motor (not shown) connected to the connecting portion 5C and a control device (not shown) for controlling the same, the fingers 6a and 6b are rotated in the D'direction and E'direction, respectively. Move to. Since the sensor 3 cannot detect the bush 7b, it is turned off. When the grip blocks 9a and 9b grip the printed circuit board 17, the grip block 9b is moved to the position shown in FIG.
As shown in FIG. 5, the spring 12 is compressed while being pushed in the E direction by the printed circuit board 17, and when a certain grip force is reached, the grip detection sensor 13 detects the end of the shaft 10 and turns on. Based on this signal, the control unit confirms that the printed circuit board 17 is gripped and stops the rotation of the motor. When the printed circuit board 17 is released, when the motor is rotated in the reverse direction, the fingers 6a and 6b move in the D direction and the E direction, respectively. Accordingly, the grip block 9b moves in the E'direction by the elastic force of the compression spring 12, and the grip detection sensor 13 is turned off when the grip detection sensor 13 cannot detect the end portion of the shaft 10. When the fingers 6a and 6b are opened to the maximum extent, the sensor 3 detects the bush 7b and is turned on, and the signal confirms that the fingers 6a and 6b are completely opened and the printed circuit board 17 is released. Stop reverse rotation of the motor.

[0006]

In the conventional hand device, it is necessary to open the fingers to the maximum extent each time the printed circuit board is gripped and released. When gripping a small printed circuit board, the gripping release is performed. There was a problem that it took time. SUMMARY OF THE INVENTION It is an object of the present invention to provide a hand device that can accurately detect when a printed circuit board is released without opening the fingers to the maximum every time the printed circuit board is gripped and released.

[0007]

In order to achieve the above object, the hand device of the present invention is provided with a feed screw rotation amount detecting mechanism for detecting the rotation amount of the feed screw.

[0008]

In the hand device configured as described above, after the fingers are opened and the grip detection sensor is turned off or on, the rotation amount from the feed screw rotation amount detection mechanism reaches a predetermined rotation amount. Then, the screw is released and the rotation of the feed screw is stopped. Therefore, according to the present invention, it is possible to accurately detect the time when the printed circuit board is released without opening the fingers to the maximum every time the printed circuit board is gripped and released.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The elements common to the drawings are designated by the same reference numerals.

FIG. 1 is a perspective view showing an embodiment of the present invention, and FIG. 2 is a front view of FIG. 1 seen from the A direction.

The present embodiment is different from the conventional example in that a feed screw rotation amount detecting mechanism 15 for detecting the rotation amount of the feed screw 5 is provided. The feed screw rotation amount detection mechanism 15 includes a slit disk 15a and an optical sensor 15b. The slit disk 15a is fixed to the end portion 5d of the feed screw 5, and the slit disk 15a also rotates as the feed screw 5 rotates. The optical sensor 15b is provided on the bracket 16 attached to the outer wall surface of the arm portion 2b of the housing 2, and when the slit disk 15a is rotating, the slit 15c (one in this example) formed in the slit disk 15a. Is detected and a pulse is output as a detection signal to a control unit (not shown). The control unit counts this pulse and detects the rotation amount of the slit disk 15a, that is, the moving distance of the fingers 6a and 6b.

Next, the printed circuit board gripping and releasing operation and the finger open / close detecting operation of the hand device of the present invention having this configuration will be described with reference to FIGS. 6, 7 and 8.

FIG. 6 is a flowchart showing the initial operation. When the hand device is started up or the size of the target printed circuit board is changed, the motor (not shown) is reversely rotated in step S ₁ according to an instruction from the control unit so that the fingers 6a, 6
b is opened to the maximum, the sensor 3 in step S ₂ is turned on, the grip detection sensor 14 in step S ₃ is Make sure that it is in the off state, and stops the reverse rotation of the motor in step S _4. If the grip detection sensor 14 is off in step S ₃ , an error signal is output and the hand device is stopped.

FIG. 7 is a flow chart showing the gripping operation. The controller repeats steps S ₁₀ , S ₁₁ , S ₁₃ , and S ₁₀ in the first gripping operation after the initial, and if the gripping detection sensor 14 is turned on in step S _11, it is determined that gripping is complete and the motor is operated in step S ₁₂ . Stop forward rotation. Control unit by the gripping operation of the second and subsequent post initials, simultaneously with the normal rotation motor in step S _10, and detects the rotation amount of the screw 5 feeding with a feed screw rotation amount detection mechanism 15. Step S ₁₁
The rotation amount of the feed screw 5 is compared with the predetermined rotation amount n ₁ by repeating steps S ₁₀ , S ₁₁ , S ₁₃ , and S ₁₄ until the grip detection sensor 14 is turned on. When the rotation amount exceeds a predetermined rotation amount n ₁ , an error signal is output because there is a trouble such as no printed circuit board to be held, and the hand device is stopped. If the gripping detection sensor 14 is turned on in step S _11, it is determined that the gripping is completed, and the normal rotation of the motor is stopped in step S ₁₂ .

FIG. 8 is a flowchart showing the releasing operation. The printed circuit board release operation, in accordance with an instruction from the control unit, at the same time reversing the motor in step S _20, the control unit sends using screws rotation amount detection mechanism 15 feed screw 5
The rotation amount of is detected. Grip detection sensor 14 in step S ₂₁ are compared to the amount of rotation of the screw 5 feed while repeating the steps S _20, S _21, S ₂₄ until turned off a predetermined amount of rotation n _2, the rotation amount of the feed screw 5 Exceeds a predetermined rotation amount n ₂ , an error signal is output and the hand device is stopped because of some trouble. After grip detection sensor 14 in step S ₂₁ is turned off, if the rotation amount of the screw 5 the feed in step S ₂₂ becomes a predetermined amount of rotation n _3, and release completion, the reverse rotation of the motor in step S ₂₃ Stop.
The predetermined rotation amounts n ₁ , n ₂ and n ₃ are set based on the positional relationship between the lead of the feed screw 5, the compression amount of the spring 10 and the sensor 13. In this embodiment, one slit is provided on the slit disk, but it is needless to say that if a plurality of slits are provided, counting can be performed in units of the rotation angle of the feed screw.

[0016]

Since the present invention is constructed as described above, it has the following effects. By providing the feed screw rotation amount detection mechanism that detects the rotation amount of the feed screw, it is possible to accurately detect the release time of the printed circuit board without opening the fingers to the maximum every time the printed circuit board is gripped and released. Therefore, the time required for gripping and releasing can be shortened.

Further, by detecting the rotation amount of the feed screw, it is possible to detect a trouble in the grip block or the grip detection sensor. Further, the present invention is applicable not only to the printed circuit board gripping hand device but also to a general hand device.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a front view of FIG. 1 viewed from the direction A.

FIG. 3 is a perspective view showing a conventional hand device.

FIG. 4 is a front view showing a conventional hand device.

FIG. 5 is a detailed view showing a part of a conventional hand device.

FIG. 6 is a flowchart showing an initial operation.

FIG. 7 is a flowchart showing a gripping operation.

FIG. 8 is a flowchart showing a releasing operation.

[Explanation of symbols]

 1 Hand device 3 Sensor 5 Feed screw 5a Right screw 5b Left screw 6a, 6b Finger 14 Grip detection sensor 15 Feed screw rotation amount detection mechanism

Claims (1)

[Claims] 1. A hand for rotating a feed screw connecting a right-hand screw and a left-hand screw to move a pair of fingers to turn on or off a gripping detection sensor provided on one of the fingers to detect the gripping. The device is equipped with a feed screw rotation amount detection mechanism that detects the rotation amount of the feed screw, and after the fingers are opened and the grip detection sensor is turned off or on, the detection amount of the feed screw rotation amount detection mechanism is set to a predetermined value. A hand device characterized in that when the rotation amount is reached, it is released and the rotation of the feed screw is stopped.