JPS5877456A - Clamping device for nut - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to means for conveying and tightening a screw from a catcher to a screw shaft.

Conventionally, in nut tightening devices, there are two methods for holding the nut, lowering it to the screw shaft, and tightening it.

That is, in the first method, the catcher holding the nut is lowered to the screw shaft and the box bit is lowered. Furthermore, this box bit fits into the hexagonal part of the nut, and at the same time the caster releases the nut and tightens it.

As a second method, a long guide pin is passed through a screw hole in a nut held by a catcher, and the tip of the guide pin is brought into contact with a screw shaft. Next, the catcher releases the nut, allowing it to fall along the guide pin, and the box bit descends to tighten the nut.

In the first method, after the catcher holding the nut was lowered to the screw shaft, the catcher was released to release the nut, which resulted in a large tightening. Furthermore, since the lowering position of the catcher must be changed depending on the height position of the screw shaft, there is a drawback that tightening at an arbitrary height cannot be performed.

In addition, in the second method, a long and thin guide pin extending from the catcher to the screw shaft must be protruded from the tip of the box bit and must be housed within the box bit during tightening, resulting in a large stroke of the box pit.

Furthermore, in both the first and second methods, when the box pit descends to the nut transferred onto the screw shaft and attempts to fit into the hexagonal part of the nut, the opposite side of the hexagon of the box pit Since only one of the apex parts of the nut was in contact with the bolt, the nut would become slanted and would slip into the screw shaft at an angle, resulting in unreliable tightening.

The present invention solves the above-mentioned drawbacks of the conventional example, and furthermore, it is possible to tighten a nut regardless of the height of the screw shaft.Hereinafter, one embodiment of the present invention will be explained based on FIGS. 1 to 14. .

First, the configuration will be explained. In FIG. 1 showing the overall configuration, A is a lifting section, B is a part of a driver, C is a catcher section, D is an escapement section, and E is a nut supply section.

First, the elevating section A is composed of an air cylinder 1, a slider 2 connected to the cylinder, and a slide shaft 3 on which the slider 2 slides.

Next, the driver part B will be explained.

4 is an electric screwdriver held by the slider 2, and the output shaft of the driver is connected to the box pit 7 via a universal joint 6 and a bit holder 6.

8 is a vacuum pipe, and bearings 9 are located at both ends of the vacuum pipe.
, 1o, the bit holder 6 is rotated. 11 is an outer cylinder fixed to the slider 2; a female taper 12 located at the bottom of the outer cylinder 11 connects the male taper 1 of the vacuum pipe 8;
3 against and received by the compression spring 14. 15 is a suction pipe which can slide inside the box bit T against a pipe spring 16.

17 is a guide bin, and a pin spring 18 is inserted into the suction pipe 16.
It can resist and slide. 13a is a joint and a vacuum source 19
The gap 2 between the bit holder 6 and the vacuum/cavity 8
gap 21 between the guide bin 17 and the suction tube 16
Air is sucked from the tip of the suction pipe 16 through the suction pipe 16.

Next, the catcher section C will be explained.

A catcher 22 can swing on a fixed support shaft 23 against a catcher spring 24. 26 is the support shaft 2 fixed with a yoke.
6 by an air cylinder 27. One end 25a of the yoke 26 is in contact with the catcher 22. The air cylinder 27 is operated by an air nozzle 28 which is operated by the rise and fall of the slider 2.

Next, the escapement section will be explained.

29 is a fixed ES block having a support shaft 30.31, 3
2 is an ES arm that swings around the support shaft 3o, and has pins 33 and 34 at both ends, and an ES rod 36 at one end.
It is connected to the bottom end of. The upper end of the ES rod 35 is pulled up by the slider 2 via a spring 36 at the upper limit of the slider 2's rise. A lower spring 37 pulls down the lower end of the ES rod 36. Numeral 38 is a long arm that swings around the support shaft 31, has a large finger 39 fixed to its tip, and further has a pin 4o in the middle. The pin 40 is connected to the ES
It is connected to the pin 33 of the arm 32 by a link 41. 4
2 is a short arm which, like the long arm 38, swings around the support shaft 31, has a small finger 43 fixed to its tip, and further has a pin 44 in the middle. The pin 44 is connected to the pin 34 of the ES arm 32 by a link 46.

Next, the nut supply section will be explained.

46 is a hopper, 47 is a scoop plate, and groove 47a has a width that accommodates the distance between the vertices of the hexagonal nut and a depth that corresponds to the thickness of the nut.
It is fixed to the lower end of a swinging rod 49 that rotates around a support shaft 48, and moves up and down inside the hopper 46. A sliding plate 60 slides on a guide shaft 62 of a fixed head regulating plate 61 toward the hopper 46 by a roller 63 at the upper end of the swinging rod 49, and a spring 6
Pull back at 4. A gate 66 is fixed to the tip of the sliding plate 60 and slides on the shade 66.

Next, the effect will be explained.

First, the nut supply relationship will be explained.

The nuts placed in the hopper 46 enter the groove 47a of the scoop plate 47 due to the upward movement of the scoop plate 47, and flow down to the shade 56 at the rising end of the scoop plate 47. Nuts in bad posture are stopped by gate 66 and returned to hopper 46.
Go back inside. By repeating this process, the leading ends of the nuts lined up on the sheet 66 flow down to the position of the small finger 43. Next, as the slider 2 descends, the elastic force of the upper spring 360 that pulls up the ES rod 36 no longer acts on the ES rod 35, but on the contrary, the elastic force of the lower spring 370 causes the ES arm 32 to swing in the direction of arrow H. move. Therefore, large finger 39
is lowered in the direction of arrow 1, and at the same time the small finger 43 is lowered in the direction of arrow ■
As the nut moves upward in the direction, the leading nut, which was stopped by the small finger 43, flows down to the position of the large finger 39 and is stopped.

Next, when the slider 2 rises, the elastic force of the upper spring 360 is stronger than that of the lower spring 37, so the ES Rondo 36 is pulled up. As a result, the small finger 43 moves down in the direction of arrow 1,
The second nut in line is held down, and at the same time, the large finger 39 moves up in the direction of the arrow ■, so that only one nut at the tip flows down to the catcher 22.

Next, the function of the dryer and the bar will be explained.

By switching the solenoid pulp 67, compressed air enters the flow path 68, operates the air cylinder 1, and enters the vacuum source 19, generates a vacuum, and passes through the joint 13 & the gap 20, 21 to the tip of the suction pipe 16. , inhale air.

The process of lowering the driver part B to attract the nut and tightening the nut will be explained in sequence.

As the driver part B descends, the guide pin 17 first
enters the threaded part of the nut N in the catcher 22, and then the tip of the suction pipe 16 comes into close contact with the end face of the nut, and the nut is sucked by the suction.

Here, the air pulp 2 operated by the slider 2
8 becomes free, and the air cylinder 27 is connected to the yoke 25.
is pulled in the direction of the arrow to swing the gear 22 in the direction of the arrow to prevent contact with the rotating box bit 7.

Subsequently, when the nut N is moved downward to the screw shaft W while adsorbing it, the guide pin 17 slides into the suction pipe 16 by the screw shaft W, and the nut N is transferred to the screw shaft W.

The suction pipe 16 presses the end face of the nut (N) that has moved to the screw shaft and transmits the rotation of the electric screwdriver 4, so the nut rotates due to the frictional resistance between the tip of the suction pipe 16 and the end face of the nut and enters the screw shaft W. . As the tightening resistance increases, the suction pipe 16 moves into the box bit T against the pipe spring 16, and the box bit 7 instead fits into the nut to perform final tightening.

Also, if the torque when the nut first enters the threaded shaft is large, the nut will not enter the threaded part due to the frictional resistance between the tip of the suction pipe 15 and the end face of the nut, but
Hold it in the correct position, that is, vertically, and the box bit 7 will descend there, so the box bit will easily fit into the nut and be tightened. In this way, the box bit 7 will descend at the height of the completed tightening. The screwdriver stops and a part of the screwdriver rises to its original position when the tightening is completed signal.

In this way, the lower limit of the box bit 7 depends on the height of the nut that has been tightened, so the tightening is done using the box bit 7.
It can be done anywhere within the stroke range of n.

In addition, in one embodiment of the present invention, even if the nut is slightly misaligned, the box bit 7 can still be attached to the nut. However, if the center of the box bit 7 and screw shaft W is determined accurately, the vacuum pipe 8
The effect of the present invention can be obtained even if the outer tube 11 is fixed to the outer cylinder 11. However, if we consider the required accuracy for centering the box bit 7 and the screw shaft W when tightening an M3 nut using the tolerance of the 11f3 standard, the hexagonal opposite side dimensions of the nut and box bit CIIB standard spanner) Minimum difference is 0.05 deception, 2
The difference in effective diameter between grade thread and female thread is minimum 0.02 Jul
.

The total is 0.07m! Unless the centers are aligned within ±0.035 as, the nut cannot be reliably tightened.

In the normal assembly process, seven-point alignment of ±0.035JII is a major obstacle to automation.

Further, the catcher 22 is forcibly moved by the cylinder 27 to prevent contact with the box bit 7, but if both the box bit 7 and the catcher 22 are wear-resistant, the catcher 22 may be forcibly moved. You don't have to move it.

In addition, as the screw shaft in the embodiment, a shaft into which the screw hole of the nut enters is provided at the entrance of the screw part, so that even if the center of the nut tightening device and the screw shaft W is slightly off, the nut can be securely tightened. It enters the threaded part and is tightened with a nut.

As described above, the present invention uses a vacuum suction method to accurately hold the nut received by the catcher with a suction pipe and select it up to the screw shaft. Fit the nut and tighten the nut, or use a suction pipe to slightly screw the nut onto the nut shaft and final tighten with a box bit. Therefore, it has great effects, such as tightening in narrow spaces, long stroke tightening, and arbitrary tightening, such as freely and accurately tightening nuts without adjusting the height.

[Brief explanation of drawings]

Fig. 1 is a front view in section of the main parts of an embodiment of the present invention, Fig. 2 is a sectional view of main parts of the catcher part and escapement part of the device, and Fig. 3 is a P-P of Fig. 2. 4 is a cross-sectional view of the suction pipe in the direction of the Q arrow in Fig. 2, Fig. 5 is a sectional view of the main part of the suction pipe in Fig. 2 which has been lowered until it adsorbs the nut, and Fig. 6 is a view of the suction pipe further from Fig. 5. lowers and tightens the nut
7 is a sectional view of a portion of the driver in FIG. 6, FIG. 8 is a sectional view of a portion of the driver in FIG. 6, and FIG. 9 is a sectional view of a portion of the supply section of this device. , Fig. 10 is a sectional view of the main part of Fig. 9 with the scoop plate raised, Fig. 11 is a view taken in the direction of the R arrow in Fig. 9, Fig. 12 is a view taken in the direction of the R arrow in Fig. 10, and Fig. 13 is a view taken in the direction of the R arrow in Fig. 10. 9 is a sectional view taken along line S-8, and FIG. 14 is an air circuit diagram of this device.

Claims (1)

[Claims] (1) A suction pipe that is rotatably and vertically movable and is provided so that it can suction the nut perpendicular to the axial direction in a vacuum state; A nut tightening device consisting of a guide pin that can be inserted into the nut and positioned to position the center of the nut. ) A box bit with a shape that can fit into a nut at the tip and is rotatable and movable up and down, and a box bit that is supported in the box bit so that it can move up and down, and attracts the nut perpendicular to the axial direction in a vacuum state. A nut tightening device comprising a suction pipe that is movable in the suction pipe, and a guide pin that is supported in the suction pipe so as to be movable up and down, is insertable into the thread diameter of the nut, and is provided so as to be able to position the center of the nut.