JPH1177453A - Multi-shaft screw tightening method and device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-shaft screw tightening method and a device thereof provided with a function preventing a condition such as disabling screw tightening from being continued, even in the case that non-uniformity of a screwing height is generated due to screw tightening abnormality in one part, when screw tightening in a plurality of parts is simultaneously advanced. SOLUTION: A bit 6 driven to rotate by a motor 8, a suction pipe 7 fitting and inserting this bit 6, bracket 10 fixing this pipe, and a lift support part 11 lifted and moved by a cylinder 14, are arranged individually in each screw 3, and a relative height position between the suction pipe 7 and the bit 6 is detected by a sensor 16. Accordingly, bite in is generated in screw tightening in one part, and even in the case of stopping screw tightening, generation of a tilt by non-uniformity of screwing height of the screw 3 is prevented in a second member 2, a condition of non-uniformity is detected by the sensor 16, the motor 8 is controlled, a screwing height is arranged in order, and screw tightening is restarted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a method for simultaneously screwing a plurality of screws into a screw hole of a second member having a plurality of screw holes through a through hole of a first member having a plurality of through holes. The present invention relates to a multi-axial screw tightening method and a device for pulling a second member into a first member and tightening the screw.

[0002]

2. Description of the Related Art For example, as shown in FIG.
Are formed with two through holes 4, 4 through which the screw 3 passes, and the second member 2 is formed with two screw holes 5, 5 into which the screw 3 can be screwed. When the screws 3 and 3 are simultaneously lowered from above and screwed into the screw holes 5 and 5 of the second member 2 disposed below the first member 1 through the through holes 4 and 4, Second member 2
Is pulled into the first member 1 and the second member 2 is screwed and fixed to the first member 1.

In order to simultaneously screw the plurality of screws 3 into the second member 2 and pull the second member 2 into the first member 1 for screw tightening, a multi-axis screw tightening as shown in FIG. The device is used. FIG. 3 shows a conventional configuration of a multi-axis screw tightening device formed to correspond to the first and second members 1 and 2 formed as shown in FIG.

In FIG. 3, two bits 26, 26 are fitted into two suction pipes 27, 27, respectively, and each bit is sucked by vacuum means (not shown) connected to each suction pipe 27, 27. The screws 3, 3 are sucked into the suction pipes 27, 27, and the tops of the screws 3, 3 are brought into contact with the tips of the bits 26, 26, respectively. Each bit 2
The motors 6 and 26 are connected to motors 28 and 28 via universal joints 29 and 29, respectively, and the bits 26 and 26 can be rotated by the rotation of the motors 28 and 28 to perform screw tightening.

The suction pipes 27 are fixed to brackets 30, respectively.
Numeral 30 is supported so as to be able to move up and down along an elevating shaft 33 which is suspended from an elevating support part 31, and springs 32, 32 are respectively provided.
Is attached to the elevating support portion 31 in a state of being urged downward by the actuator. The motors 28 are fixed to a lifting support 31, and the lifting support 31 is connected to a cylinder 34.
, And is urged downward by a spring 35 inserted into the piston rod of the cylinder 34.

As shown in FIG. 3, each suction pipe 27, 2
When the lifting support portion 31 is lowered to the screw tightening position by the cylinder 34 in a state where the screws 3 and 3 are sucked into 7, the screws 3, 3
When each of the suction pipes 3 passes through the through holes 4 and 4 of the first member 1 held at a predetermined position and comes into contact with the screw holes 5 and 5 of the second member 2, each of the suction pipes 27 contacting the first member 1 , 27 are raised against the force of the brackets 30, 30 urged by the springs 32, 32, and the lifting support 31 is urged in the downward direction by the spring 35, so that the motors 28, 28 Are screwed into the screw holes 5, 5 of the second member 2, the second member 2 is pulled into the first member 1, and the second member 2 is It can be fixed to the member 1 with screws.

[0007]

However, in the above-mentioned conventional structure, each bit 26, 26 is connected to each motor 28, 28 fixed to one elevating support portion 31,
Since each of the bits 26, 26 is configured to be able to perform screw tightening at the same time, when one of the plurality of screws 3 bites into the screw hole 5, the rotation of the bit 26 is stopped. However, as a result of the screwing of the other screw 3 operating normally leading up, there is a problem that the second member 2 is inclined and the screw tightening cannot be continued.

An object of the present invention is to provide a multi-axial screw tightening method and a multi-axial screw tightening method in which the progress of the screw tightening by each bit in the multi-axial screw tightening is executed in synchronization.

[0009]

According to a first aspect of the present invention, a first member having a plurality of through holes is held at a predetermined position, and a plurality of first members are provided below the first member. By arranging a second member having a screw hole formed therein and simultaneously screwing a plurality of screws into the respective screw holes through the respective through holes, the second member is pulled into the first member and screwed. In the shaft screw tightening method, a bit, which is driven to rotate by a motor and performs screw tightening, is individually moved in a screwing direction of each screw, and a height at which each bit screwes a screw into the second member. Each position is detected, and the screws are tightened so that the screwed height positions are equal.

According to the above multi-axis screw tightening method, each bit can be individually moved in the screwing direction of the screw.
Since the height position where the screw is screwed into the member is detected, when the screw tightening of one bit is delayed due to the biting of the screw or the like, the rotation of the other bit to be preceded is stopped, and the rotation of all the bits is stopped. After the height positions of the screws are made equal, screw tightening is resumed. Therefore, it is possible to prevent the occurrence of a trouble that the second member is inclined due to the degree of progress of the screw tightening by each bit and the screw tightening cannot be continued.

A second invention of the present application is directed to a plurality of bits which are rotationally driven by a motor, and a plurality of suction holes which are inserted and supported so as to be able to move up and down in the bit axis direction and are urged in the bit tip direction. A pipe, and sucking the screw by each suction pipe to hold the screw at the tip of each bit, moving each bit and each suction pipe downward to the screw tightening position, and biasing in the screw screwing direction. The screws held by the respective bits pass through the plurality of through holes formed in the first member held at the predetermined positions, and the suction pipe contacting the first member retreats against the bias. In the multi-axis screw tightening device, the screw held by each bit is screwed into each screw hole of the second member disposed below the first member, and the second member is drawn into the first member and screwed. Each bit and A plurality of elevating and lowering support portions for supporting and moving each of the suction pipes, a plurality of elevating and lowering driving means for driving each of the elevating and lowering support portions up and down, and a plurality of relative positions for detecting a relative position between each bit and the suction pipe It is characterized by comprising detection means and control means for controlling the rotation of the motor based on the detection value of the relative position detection means.

According to the above configuration, since the relative position between each bit and the suction pipe into which the bit is inserted is detected, the amount of advance of the screw into the second member by the bit is detected.
Even when the screw tightening by one bit is jammed and the screw tightening is stopped, this is detected by the relative position detecting means, so that the screw tightening of the other normally operating bits is temporarily stopped. Then, the preceding operation of screw tightening is stopped, and screw tightening can be resumed after the screw tightening heights of all the bits are aligned. Also, in such a case, when there is a difference in the screw insertion height of each bit,
Since each bit is individually supported by the elevating and lowering support portion, and the biasing force in the screw tightening direction is individually applied, the inclination of the second member due to the progress of the screw tightening being different for each bit does not occur, and A situation in which the screwing operation becomes impossible due to the inclination of the two members is prevented.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention.
As shown in FIG. 2, the multi-axis screw tightening device shown in this embodiment passes the screws 3, 3 through two through holes 4, 4 formed in the first member 1 held at a predetermined position. 2, two screw holes 5, 5 formed in the second member 2 disposed below
, The second member 2 can be drawn into the first member and screwed.

In FIG. 1, in the multi-axis screw tightening device according to the present embodiment, two bits 6, 6 are inserted into two suction pipes 7, 7, respectively. The screws 3, 3 are sucked into the suction pipes 7, 7 by vacuum suction by a suction means (not shown) connected thereto.
3 is brought into contact with the tip of each bit 6, 6 respectively,
Screws can be tightened by rotation of motors 8, 8 connected to the respective bits 6, 6 via universal joints 9, 9, respectively.

The suction pipes 7, 7 are fixed to brackets 10, 10, respectively.
Are supported to be able to move up and down along a common elevating shaft 13, and are attached to the elevating and lowering support parts 11, 11 in a state of being urged downward by springs 12, respectively. The motors 8, 8 are fixed to the lifting support portions 11, 11, respectively. The lifting support portions 11, 11 are driven up and down by the cylinders 14, 14, respectively, and are inserted into the piston rods of the cylinders 14, respectively. The springs 15 are urged downward.

A dog 1 for detecting a position of the suction pipe 7 is provided at a predetermined position of each of the brackets 10, 10.
7 and 17 are attached.
The ascending and descending position is detected by the sensors 16 and 16 disposed at predetermined height positions hanging down from the ascending and descending support portions 11 and 11, respectively.

As shown in FIG. 1, when the lifting support portions 11, 11 are lowered to the screw tightening positions by the cylinders 14, 14 while the screws 3, 3 are sucked into the suction pipes 7, 7, each bit Each of the suction pipes 7 contacting the first member 1 by passing the screws 3 held at the distal end of the first member 1 through the through holes 4 of the first member 1 held at a predetermined position. , 7 retreat each bracket 10, 10 against the force urged by each spring 12, 12, so that each motor 8,
The tip of each bit 6, which is rotationally driven by 8, advances to the tip of each suction pipe 7, and screws 3, 3 are screwed into screw holes 5, 5 of the second member 2, and each spring 15 , 15 urge the lifting support portions 11, 11 in the descending direction to be pressed in the screwing direction. The second member 2 is pulled in as the screwing proceeds, and is fixed to the first member 1 by screwing.

In a state where the screws 3 are screwed in by the respective bits 6, 6 in a synchronized manner, the smooth screw tightening operation is performed as described above. However, if an abnormality occurs such that the screw 3 being screwed by one of the bits 6 bites into the screw hole 5, the screwing of the screw 3 by the bit 6 is temporarily stopped. , The screwing of the other normally operating bit 6 precedes. In the state where the screw tightening of one bit 6 is stopped, a difference occurs in the screwing height of the screw 3 between the bits 6, 6. Are detected by the sensors 16 and 16 which detect the relative position between the two.

When it is detected by each of the sensors 16 and 16 that a difference occurs in the screwing height of the screw 3 by each of the bits 6, 6, the rotation of the bit 6 other than stopped by biting of the screw is immediately stopped. Stopped, the bit 6 temporarily stopped by the biting is released, the bit 3 is released, the screw 3 is screwed in, and the screwing height positions of all the bits 6 are aligned.
That is, the screw tightening operation is restarted with the values detected by the sensors 16 and 16 being constant.

Further, when the rotation of one bit 6 is stopped by the biting of the screw 3 and the screw 3 is screwed in by the other bit 6 first, the second member 2 is inclined and the screw tightening operation is performed. Although the continuation becomes impossible, since the lifting / lowering support portions 11 are individually provided for each of the bits 6 and 6, even if a difference occurs in the screwing height between the bits 6 and 6 due to abnormality, The elevating and lowering support portion 11 being biased by the spring 15
Changes to a descending amount in accordance with the screwing amount of the screw 3 by the bit 6 supported by each, so that the second member 2 does not tilt due to the difference in screwing height, and the screw tightening operation is not performed. Conditions that make it impossible to continue are avoided.

In the above-described configuration, the configuration in which the two screws are simultaneously tightened has been described. However, a plurality of similar configurations are arranged in accordance with the number of screw tightening points, and the screw insertion height of each bit is set. Is detected and controlled so as to be equal, the operation of tightening the multi-axis screw can be stably executed.

[0022]

As described above, according to the present invention, each bit can be individually raised and lowered, and the height position at which the screw is screwed into the second member is detected. When the screw tightening of one bit is delayed, the rotation of the other bit to be preceded is stopped, and the screw tightening is resumed after the height positions of the screw-in of all the bits are equalized. Therefore, it is possible to prevent the occurrence of a trouble that the second member is inclined due to the difference in the degree of progress of the screw tightening by each bit and the screw tightening cannot be performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a configuration of a multiaxial screw fastening device according to an embodiment of the present invention.

FIG. 2 is a sectional view showing an example of a member to be screwed;

FIG. 3 is a configuration diagram showing a configuration of a conventional multi-axis screw fastening device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st member 2 2nd member 3 Screw 6 Bit 7 Suction pipe 8 Motor 10 Bracket 11 Elevation support part 12 Spring 14 Cylinder (drive means) 16 Sensor

Claims (2)

[Claims] 1. A first member having a plurality of through holes formed therein is held at a predetermined position, a second member having a plurality of screw holes formed below the first member, and a plurality of screws are formed. By simultaneously screwing into each of the screw holes through each of the through holes,
In the multi-axis screw tightening method of pulling the second member into the first member and tightening the screw, a bit which is driven to rotate by a motor and tightens the screw may be individually moved in the screw insertion direction for each screw. A multi-axial screw tightening method, wherein each bit detects a height position at which a screw is screwed into the second member, and tightens the screws so that the screwed height positions are equal. . 2. A plurality of bits rotatably driven by a motor, and a plurality of suction pipes into which the bits are inserted and urged toward the tip of the bits, wherein each of the suction pipes suctions a screw to suck each screw. By holding the screw at the end of the first and lowering each bit and each suction pipe to the screw tightening position and energizing in the screw screwing direction, the screw held by each bit is held at the predetermined position. When passing through the plurality of through holes formed in the member, the suction pipe in contact with the first member retreats against the bias, and each bit advanced to the tip position of the suction pipe connects each screw to the first member. A multi-axis screw tightening device for screwing into each screw hole of the second member disposed below the first member, pulling the second member into the first member and tightening the screw, supporting each of the bit and the suction pipe Multiple ascending The support part, a plurality of elevating drive means for driving each elevating support part up and down, a plurality of relative position detecting means for detecting a relative position between the suction pipe and the bit for each bit, and a plurality of relative position detecting means. Control means for controlling the motor based on a detected value.