JPS6222734B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to an automatic screw tightening machine that tightens screws horizontally.The present invention relates to an automatic screw tightening machine that tightens screws in a horizontal direction. It captures the screw and moves it to tighten the screw.

A conventional example of a screw tightening machine that tightens screws in a horizontal direction will be explained with reference to FIG.

In this conventional example, the screws aligned on the chute are
Separate each piece, drop it into the pipe, introduce air at several atmospheres into the pipe, force feed the screw, and
Y pipe 101 in a horizontal state as shown in Figure 1
The screw is captured by a pair of jaws 102 attached to the Y pipe 101 that open and close left and right or up and down, and the Y pipe 101 is moved close to the tightening diagram, and the screwdriver's rotation is transmitted to the bit 10.
3 was moved forward to tighten the screws.

In the above conventional example, in order to force feed the screw 103,
A pressure-feeding pipe is used, but the inner diameter of this pipe is slightly larger than the screw head diameter (if the pipe inner diameter is too large, air will leak from the gap between the pipe and the screw head and pressure-feeding will not be possible). However, since the inner diameter of the pipe needs to match the head diameter, it has the disadvantage of lacking in versatility.

A method that does not use a pressure pipe is to run screws horizontally on the chute in an almost vertical position.
There was one in which the bits were adsorbed by suction pipes placed concentrically inside, the screws were suctioned inside by vacuum suction, and the screws were tightened after being moved to a horizontal position in this state.

However, in such cases, it is necessary to move the suction pipe and the screw tightening bit back and forth from a vertical position to a horizontal position each time a screw is tightened, which increases the overall size of the device and increases the amount of time needed to tighten one screw. It had the disadvantage that it took a lot of time.

The present invention eliminates the above-mentioned drawbacks, and one embodiment of the present invention will be described below with reference to FIGS. 1 to 9.

FIG. 1 is an overall view showing one embodiment of the present invention.
2 is a hopper section, 2 is a chute section, 3 is an escape section, 4 is an attitude change section, 5 is a catch section, and 6 is a driver section. First, the overall movement will be briefly explained.

The screws S supplied from the hopper section 1 are aligned in the chute section 2, separated one by one by the escape section 3, and supplied to the attitude changing section 4. Here, the screw is changed from an oblique position to a direction in which the threaded portion becomes horizontal, and is supplied to the catcher section 5. The driver part 6 attracts the screw S and completes tightening while moving forward.

Next, details will be explained.

First, the structure of the escape section 3 will be explained. 8 is
It is an ES slider and can slide within the ES base 9. 10 and 11 are ES fingers, which are screwed to the ES slider 8, and screwed to the screw S on the chute.
can be locked. A spring 12 presses the ES slider 8 in the direction of arrow a. 13 is a cam roller.

Next, the posture changing section 4 will be explained. Reference numeral 14 denotes a single acting cylinder, which is connected to a rack 16 via a connector 15. The cam surface 16a of the rack 16 can abut against the cam roller 13 at the return limit. 17 is a forward stopper for the single acting cylinder 14. 1
8 is a pinion that engages with the rack 16 and is fixed to the shaft 19. 20 is a support bracket,
It rotatably receives the shaft 19 via a bearing 21. 22 is a bearing that enables the rocking body 23 to rotate on the shaft 19. A plate cam 24 is fixed to the shaft 19 and is always in contact with a cam roller 26 attached to a push block 25 by a spring 27. Further, the plate cam 24 pulls the rocking body 23 by the tension spring 28, and the plate cam 24
A stopper 29 fixed to the oscillator 23 is brought into contact with the stopper 29 . 30 is an upper limit stopper of the swinging body 23, 31 is a screw presser that can swing around the intersection pin 32, and 33 is an opening bar that opens the screw presser 31 against the torsion coil spring 34.

Next, the catch section 5 and driver section 6 will be explained. Fulcrum pin 3 of catcher base 35
A catcher 37 which can swing about 6 is brought into contact with a stopper 39 by a tension coil spring 38. 40 is a screw head support plate, which is firmly fixed to the catcher 37. Reference numeral 41 denotes a screw head guide, and there are a pair of left and right screw head guides, each of which has a lever 43 that swings around a fulcrum 42.
It is stuck to. The lever 43 is opened by a tension coil spring 44 and closed by a spring 46 via a rod 45. A suction pipe 47 is screwed to a vacuum pipe 48 and supported by a guide 49. The vacuum pipe 48 is slidable in the axial direction within an outer cylinder 50 held by a slider 49 (not shown). 51 is a bit, bit holder 52
The screwdriver 53 is screwed to the outer cylinder 50 and connected to the driver 53 held by the outer cylinder 50. 54 is a cylinder that slides the slider 49 onto the slide shaft 55. 56 is an air valve, and 57 is a micro switch, each of which operates at the return limit of the slider 49.

Next, the action will be explained.

A start signal activates the cylinder 54 and moves the slider 49 forward. First, the operation of the air valve 56 is turned off, and the air flowing into the single-acting cylinder 14 is stopped. As a result, the rack 16 begins to return, causing the shaft 19 to rotate and the plate cam 24,
The swinging body 23 also begins to return and moves until it comes into contact with the upper limit stopper 30. At the same time, the screw retainer 31 is also opened by the release bar. The ES slider 8 is actuated by the cam surface 16a of the rack 16, separates one screw, and supplies it to the swinging body 23.

On the other hand, as the slider 49 moves forward, the elastic force of the spring 46 becomes weaker, so that the screw head guide 41 opens left and right due to the elastic force of the tension coil spring 44. At the same time, since the suction pipe 47 is moving forward, it begins to suction the screw. Further, the suction pipe 47 suctions the screw, tilts the catcher 37, and removes the bit 5.
1, and tighten the screws (see Figure 4). In response to the screw tightening completion signal, the driver section 6 moves backward and operates the air valve 56 at the return limit.
As a result, the single-acting cylinder 14 begins to move forward, causing the shaft 19 to rotate. As a result, the rocking body 2
3 leaves the upper limit stopper 30, and at the same time, the screw presser 31 also leaves the release bar 33, and the elasticity of the torsion coil spring 34 presses the screw. In this state, the swinging body 23 swings until it hits the lower limit stopper 58. (See Figure 5) From here, only the plate cam 24 resists the tension spring 28 and swings, so the push block 25 is moved by the spring 27.
The driver moves forward to push out the screw against the force, and pushes the screw into the catcher 37. Here, single acting cylinder 1
4 hits the forward stopper 17, and the swinging of the plate cam also stops (see Fig. 6). By repeating the above cycle, continuous tightening can be achieved.

Next, the air circuit will be explained based on FIG. A solenoid valve 59 changes the direction of compressed air and operates the cylinder 54. Now, when current flows through the coil of the solenoid valve 59 and the solenoid valve 59 operates, the direction of the air changes, and the air flows through the cylinder port 54a through the pipe 60 and the regulator 61 where the air can flow backwards.
Since air enters the cylinder 54, the cylinder 54 moves forward. The regulator 61 adjusts the pressing force of the bit 51 connected to the cylinder 54. The other air enters the supply port 62a of the vacuum generator 62 (ejector type or bench lily type is suitable),
It passes through the exhaust port 62b and chi 63 and is released into the atmosphere from the muffler 64, so a vacuum is generated at the suction port 62c, passes through the filter 65 and the vacuum pipe 48, and the screw is sucked at the tip of the suction pipe 47. . In this way, screw tightening is completed.

Next, when the solenoid valve 59 returns to its original state, the indoor air of the air cylinder 54 is transferred to the port 54a and the regulator 6.
1, enters through the exhaust port 62b of the vacuum generator 62 through the pipes 60, 61 and Qi 63, reaches the suction port 62c, filter 65, vacuum pipe 48, and adsorption pipe 47, and is discharged into the atmosphere. For this reason, the screws remaining due to poor screw tightening are discharged, the surrounding dust and the dust caused by the tapping screws are discharged, and the suction circuits such as the vacuum generator 62 and the filter 65 are cleaned. In this case, the chi 63 is such that the exhaust port 62b and the pipe 66 are in a straight line.
A muffler 64 is formed in a direction perpendicular to the straight line, and the air flowing through the pipe 66 passes through the muffler 6.
Suppress the discharge to 4.

Furthermore, if the solenoid valve 59 is of a type that seals only at both switching ends of the spool, the supply port 59a and the exhaust port 59b leading to the pipe 66 are connected at the time of switching, and air further flows into the pipe 66, so that even greater effects can be obtained.

In the above embodiment, the pushing block 25 is provided to push the screw into the catch 37, but this is effective for unstable screws such as those having a short under-neck dimension. In other words, if the screw is sufficiently long under the neck, the screw will fall into the catcher 37 simply by opening the screw retainer 31 without having to push it out.

In order to open the screw presser 31, a convex portion is provided at the tip of the plate cam 24 to press the rear end of the screw presser 31, or a stopper is provided that also hits the tip of the screw presser 31 at the same time as the swinging body 23 hits the lowering stopper 50. This can be easily implemented by

Further, the screw head guide 41 is similarly effective for unstable screws such as those with short neck dimensions. In other words, a sufficiently long screw under the neck enters the catcher 37 without the screw head guide 41 and without turning over.

Further, in one embodiment of the present invention, the head of the screw is restricted by the swinging body 23 and the screw retainer 31, but the same effect can be obtained by gripping the lower part of the neck of the screw.

Also, when pushing out the screw with the push block 25, the same effect can be obtained by pushing the screw head or the lower part of the neck.

As described above, the present invention uses a screw tightening machine that has an integrated screw hopper section, grips the supplied screw with the oscillating body, holds the screw in the catcher while keeping it horizontal, and then tightens it after being sucked. Not only can you horizontally tighten short screws under the neck, which was considered difficult, but you can also reliably tighten long screws under the neck. In addition, since the screw supply section is integrated with the tightening section, there are advantages such as a simpler mechanism, easier maintenance and inspection, and a smaller installation space, compared to a system that pumps screws.

Furthermore, even if the shape of the screw head changes, there is no need to change the pressure feeding route, Y pipe, catcher, etc. unlike in the pressure feeding method, and it has great effects such as great versatility.

[Brief explanation of the drawing]

Fig. 1 is a front view of a screw tightening device according to an embodiment of the present invention, Fig. 2 is a bottom view of the same device, Fig. 3 is a view of the same device in the direction of arrow A, and Figs. 4 to 7 are main parts of the device. 8 is a sectional view taken along arrow B in FIG. 7, FIG. 9 is a sectional view taken along arrow C in FIG. 7, and FIG. 10 is an air circuit diagram of a screw tightening device according to an embodiment of the present invention. The figure is a half sectional view showing a conventional example. 1...Hopper part, 2...Chute part, 3...
Escape part, 4...Position changing part, 5...Catcher part, 6...Driver part, 14...Single acting cylinder, 16...Rack, 18...Pinion, 19...
...shaft, 23 ... rocking body, 24 ... plate cam,
25...Push block, 29...Stopper, 3
0... Upper limit stopper, 31... Screw retainer, 3
2... Fulcrum pin, 33... Release bar, 37... Catcher, 41... Screw head guide, 43... Lever, 47... Suction pipe, 48... Vacuum pipe,
49...Slider, 51...Bit, 53...
Driver, 54... cylinder, 56... air valve.

Claims (1)

[Scope of Claims] 1. A chute section provided at an inclination so as to convey the screws supplied from the screw supply section in a line in a hanging state, and a chute section that is arranged to transport the screws one by one near the rear end of the chute section. an escape part provided to be separated; an attitude change part for changing the screw supplied from the escape part from a hanging state to a state in which the screw shaft is in a horizontal state;
A catcher part is provided to receive the screw in which the screw shaft supplied from the attitude changing part is in a horizontal position, and the screw shaft held by this catcher part is attracted to the screw in a horizontal state. It consists of a pipe and a driver part that is rotatably driven in the pipe and is equipped with a bit that rotates a screw. , an automatic screw tightening machine having a rocking body provided to support a screw from an escape part, a gripping means for gripping the screw supported by the rocking body, and a release means for releasing the grip by the gripping means. . 2. The attitude changing part is rotatable about one point, and has a tip connected to the rear end of the chute part, and includes a swinging body provided to support a screw from the escape part, and a screw supported by this swinging body. A screw retainer is provided on the rocking body and is biased to press down on the head of the rocker, and a plate cam that is rotatable coaxially with the fulcrum of the rocker. a push block that is provided integrally with the cam roller, is slidable within the oscillating body, and is attached so as to push out the screw held by the screw holder and the oscillating body to the catch portion; Claim 1 having
Automatic screw tightening machine as described in section.