JPS63212424A - Automatic screw tightening device - Google Patents

Abstract

PURPOSE:To prevent a device from becoming large-sized and prevent inability of work due to variance in a screw pitch from occurring by using a resilient force of a spring for part of the actions of picking up or tightening the screw. CONSTITUTION:Actuating a moving mechanism 20, an air screwdriver or the like is moved to above a screw 60 to be picked up and then lowered toward the screw 60. In the middle of the above-mentioned action, a screwdriver head 43 projecting from a finger mechanism 50 comes into contact with the head of the screw 60. The air screwdriver 41, while resisting a resilient force of a screwdriver spring 42, moves upward relative to a vertical movement frame 30. Under this condition, the finger mechanism 50 is actuated to hold the screw 60 with a holding section 55. Moving then to a position where the screw is to be fitted, the air screwdriver 41 is lowered with a vertical movement mechanism. Thus, the device is prevented from becoming large-sized.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an automatic screw tightening device, and more specifically, a series of operations from picking up a screw at a predetermined position to moving it to a screw tightening position and tightening the screw. This invention relates to an automatic screw tightening device that can automatically perform the following steps.

[Prior Art] Conventionally, various automatic screw tightening devices have been provided for efficiently tightening screws.

Some of the automatic screw tightening devices that have been provided in the past require manual labor for part of the process from picking up a screw to tightening the screw in a predetermined position.

On the other hand, some machines automatically control all operations from picking up a screw to completing the screw tightening process.

[Problems to be Solved by the Invention] However, among the conventional automatic screw tightening devices as described above, some of the screws are manually set. In the case of methods such as those carried out by other means, there is a decrease in work efficiency and the method lacks practicality.

On the other hand, in devices where all operations are automatically controlled, variations in the dimensions of the screws themselves may cause the entire device to stop operating.

Therefore, the present invention is an automatic screw tightening device that picks up a screw, moves the screw to a predetermined position, and then tightens the screw. The purpose is to provide an automatic screw tightening device that uses the elastic force of a spring to prevent the overall size of the device from becoming large, and also prevents the device from becoming inoperable due to variations in the pitch of the screws. do.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the present invention includes a vertically movable frame that can be moved up and down by a vertical movement mechanism on a guide shaft provided on a fixed frame fixed to a moving mechanism. A slide shaft is fixed to this vertically movable frame, and the driver frame and finger frame are supported so that they can be moved vertically parallel to the slide shaft while being pressed downward by a spring, and an air driver is provided on the driver frame. , the finger frame is provided with a finger mechanism for grasping the screw, and the driver head at the tip of the air driver is formed so as to protrude downward from the lower end of the finger mechanism in a normal state.

[Operation] The automatic screw tightening device according to the present invention first picks up a screw at a predetermined position, then moves it to the location where the screw is to be tightened, and then tightens the screw.

To explain in more detail, first, the moving mechanism moves the air driver or the like above the screw to be picked up.

In this state, since no external force is applied, the driver head at the tip of the air driver protrudes downward from the lower end of the finger mechanism.

Thereafter, an air driver or the like is lowered toward the screw using a vertical movement device.

During the descent of the air screwdriver, etc., the driver head first comes into contact with the screw head.

However, since the air screwdriver etc. is further lowered by the vertical movement device, the driver head that has contacted the screw head remains in that position and is then lowered until the lower surface of the finger mechanism reaches the vicinity of the screw holding surface. The air driver moves upward against the vertically moving frame while resisting the spring force of the spring.

In this state, the finger mechanism is operated and the screw is held by the finger mechanism. Further, even when the screw is held by this finger mechanism, the tip of the screw protrudes below the lower surface of the finger mechanism.

Thereafter, the vertical movement mechanism raises the air driver or the like while holding the screw, and the moving device moves the air driver or the like to the location where the screw is to be tightened.

After the air driver, etc. has been moved to the position where this screw tightening is to be performed, the air driver, etc. is lowered by the vertical movement mechanism.

During this descent, the tip of the screw first comes into contact with the workpiece to be screwed.

Next, the air driver moves against the vertically moving frame.
The lower surface of the finger mechanism comes into contact with the work while moving upward against the elastic force of the spring.

Even after the finger mechanism contacts the workpiece surface in this way, the air driver or the like is further lowered by a predetermined amount by the vertical movement mechanism.

After completing a predetermined amount of descent in this way.

The air driver starts rotating and tightens the screw, and the finger mechanism opens to release the screw.

This tightening of the screw is performed by the rotation of the air driver and the elastic force of a spring that pushes the air driver downward.

Further, the tightening of the screw is completed by detecting a predetermined rotation, a predetermined descent, or a change in the load on the air driver.

Therefore, the automatic screw tightening device according to the present invention is as follows.

By controlling the vertical movement device and the moving device and actually tightening the screws using the elastic force of the spring, it is possible not only to automate screw tightening but also to downsize the entire device.

Note that when tightening the screw, depending on the workpiece, the lower surface of the finger mechanism may come into contact with the workpiece, causing damage to the workpiece and reducing its commercial value. In such a case, damage can be prevented by stopping the vertical movement mechanism from descending just before the lower surface of the finger mechanism contacts the workpiece.

[Example] An embodiment of the present invention will be described below with reference to illustrated examples.

Figure 1 is a partially sectional front view, Figure 2 is a plan view, and Figure 3 is a partially sectional front view.
The figure is a sectional view showing an example of the vertical movement mechanism 10.

In the embodiment shown in FIGS. 1 and 2, a guide shaft 22 provided on a fixed frame 21 fixed to a moving mechanism 20 has a
Vertical movement frame 3 that can be moved vertically by vertical movement mechanism lO
0 is the default.

Any type of moving mechanism 20 can be used as long as it is capable of moving the fixed frame 21 along a planar x-y table or a three-dimensional x-y-z table. .

The fixed frame 21 is formed in a two-character shape from the front, and two guide shafts 22 are fixed to the middle portion thereof.

One side of the vertically moving frame 30 is pivotally supported by two guide shafts 22, and the vertically moving frame 30 is slidable in the vertical direction by the vertically moving mechanism 10.

The other side of the vertically movable frame 30 is formed in a double-shape, and two slide shafts 31 having shaft ends projecting downward are fixed to the intermediate portion thereof.

The upper ends of the two slide shafts 31 are both fixed to the upper part of the vertical movement frame 30.

The middle part is fixed to the lower part of the vertically movable frame 30, and the lower end part is fixed by a fixed body 32.

In addition, an air driver 4 is connected to the middle part of the vertical movement frame 30 of the slide shaft 31 via a driver frame 40.
1 is fixed, and this driver frame 40
A driver spring 42 is arranged between the upper end surface of the vertically movable frame 30 and the upper part of the vertically movable frame 30, so that the driver frame 40 is pressed downward in a normal state.

Note that driver heads 43 of various sizes can be fixed to the tip of this air driver 41.

Further, a finger mechanism 50 is fixed to the protruding portion of the slide shaft 31 from the vertically movable frame 30 via a finger frame 51.
A finger spring 52 is disposed between the upper end surface of the frame 1 and the lower part of the vertically movable frame 30, so that the finger frame 51 is pressed downward in a normal state.

Further, the finger mechanism 50 includes a mechanical finger 53
and two finger attachments 54 having screw holding portions 55 at their tips, and the tips of the finger attachments 54 are opened and closed by a predetermined input. In addition, the two wooden finger attachments 54 are
Even when the screw is held by closing,
A screw holding portion 55 is formed by a closed finger attachment 54 rather than a fixed holding portion.
It is kept movable by.

Note that when the screw 60 is not held, the finger mechanism 50 is in a state where the finger attachment 54 is open.

At this time, both the driver frame 40 and the finger frame 51 are moved up and down by the driver spring 42 and the finger spring 52, respectively.
0 lower part and the fixed body 32.

Also, the positional relationship at this time is finger attachment 5.
The lower end of the driver pad 43 protrudes more downward than the lower end surface of the driver pad 43.

The sectional view shown in FIG. 3 shows an example of the vertical movement mechanism IO.

In this embodiment, the cylinder 11 provided on the fixed frame 21 is
A piston 12 is installed inside the cylinder 11, and the cylinder 11 itself, which is fixed to the vertical movement frame 30, is moved up and down depending on which part of the upper or lower part of the piston 12 is pressurized with air inside the cylinder 11. .

In this way, the vertical movement mechanism 10 is not limited to the embodiment, and other means can also be used.

Next, regarding the operation of the automatic screw tightening device shown in the embodiment, first, the screw 60 at a predetermined position is picked up, and then the screw 60 is moved to a place where the screw is to be tightened.
The work to complete the tightening process will be explained in order.

First, by operating the moving mechanism 20, the air driver 41 etc. is moved to an arbitrary position, a set position, or a position where screw tightening is completed.
1st class is moved above the screw 60 to be picked up.

In this state, the tip of the finger attachment 54 is open and no external load is applied, so the air driver 43 is applied to the driver at the tip of the air driver 41.
protrudes below the lower end of the finger mechanism 50.

When the predetermined position is reached, the air driver 41 and the like are then lowered toward the screw 60 by the vertical movement device.

During the descent of this Air Driver 41 etc.

First, the driver head 43 that protrudes below the lower end of the finger mechanism 50 comes into contact with the screw 60 heads.

However, since the air driver 41 and the like are further lowered by the vertical movement device, the driver head 43 that has contacted the 60 screws remains in that position and is then lowered until the lower surface of the finger mechanism 50 reaches the vicinity of the holding surface of the screw 60. will be carried out. At this time, the air driver 4-1 cannot be lowered any further because the driver rod 43 is in contact with the 60 screws, and the air driver 4-1 moves upward against the vertically moving frame 30 while resisting the elastic force of the driver spring 42. It is something that moves to.

In this state, the finger mechanism 50 is operated, and the screw 60 is held in the screw holding portion 55 by the finger 1 mechanism 50. Further, even when the screw 60 is held by the finger mechanism 50, the screw 60 is not held fixedly in the screw holding portion 55, but is held with some play.

Thereafter, the air driver 41 and the like are raised while the screw 60 is held in the screw holding portion 55 by the vertical movement mechanism IO.

During this upward movement, the finger mechanism 50 rises first, and then the air driver 41 rises.

Therefore, the screw 60 held by the screw holding part 55 after being raised is held while being pressed by the screw holding part 55 by the elastic force of the driver spring 42. Further, at this time, the lower end of the screw 60 projects downward from the screw holding portion 55.

After holding the screw 60 in the screw holding part 55 in this way,
The air driver 41 and the like are moved to the location where screw tightening is to be performed using the moving device.

After the movement of the air driver 41 and the like to the position where this screw tightening is completed, the air driver 41 and the like are lowered by the vertical movement mechanism 10.

During this lowering, first, the tip of the screw 60 protruding downward from the screw holding portion 55 comes into contact with a workpiece (not shown) to be screwed.

However, since the vertical motion device continues to descend, the air driver 41 moves upward against the vertical motion frame 30 against the elastic force of the spring, and connects the finger attachment 54 which is the lower surface of the finger mechanism 50. comes into contact with the workpiece.

Even after the finger attachment 54 comes into contact with the workpiece surface in this manner, the air driver 41 and the like are further lowered by a predetermined amount by the vertical movement mechanism 10.

After the predetermined amount of descent is completed in this way, the air driver 41 starts rotating to tighten the screw 60, and the finger attachment 54 opens.
This means that the screw 60 is released.

Of course, as long as the stability of the screw 60 can be ensured,
The screw 60 may be tightened after the finger attachment 54 is opened.

Further, such tightening of the screw 60 is performed by the rotation of the air driver 41 and the elastic force of the driver spring 42 that pushes the air driver 41 downward.

Therefore, depending on the pitch of the screw 60, etc., the air driver 4
There is no need for means such as controlling the descending speed of 1.

Further, the tightening of the screw 60 is completed by detecting a predetermined rotation, a predetermined descent, or a change in the load on the air driver 41.

In the above explanation, a U-shaped part is formed in the vertically movable frame 30, and two slide shafts 31 with shaft ends protruding downward are fixed to the middle part of this U-shaped part. The driver frame 40 is pivotally supported on the vertically movable frame 30 portion of the slide shaft 31, and the vertically movable frame 3 of the slide shaft 31
Although the explanation has been made assuming that the finger frame 51 is fixed to the lower part of the 0 part, for example, the driver frame 40 is pivotally supported on the slide shaft 31, and the finger frame 51 is fixed to the guide shaft 2.
It can also be pivoted to 2.

However, at this time, a U-shaped portion may be formed in the vertically movable frame 30 through which the guide shaft 22 passes, and the finger frame 51 pressed downward by the finger spring 52 may be positioned in the U-shaped portion.

In addition, in the above explanation, when tightening the screw 60 to the workpiece, the finger attachment 54 is brought into contact with the workpiece, and then the vertical movement frame 30 is lowered slightly before the screwing is performed. Some items may be damaged by contact with the finger attachment 54, reducing their commercial value. In such a case, the product value can be reduced by limiting the amount of descent of the vertically movable frame 40 or installing a stopper (not shown) to prevent the finger frame 51 from lowering beyond a certain level. It is also possible to prevent a decrease in

Further, the driver head 43 and the finger attachment 54 can be changed depending on the diameter of the screw 60 used.

[Effects of the Invention] As explained above, the present invention is an automatic screw tightening device that picks up a screw, moves the screw to a predetermined position, and then tightens the screw. By using the elastic force of the spring as part of the operation when tightening the screw, it is possible to prevent the overall size of the device from increasing.

This prevents inoperability due to variations in the pitch of the screws, etc.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which FIG. 1 is a partially sectional front view, FIG. 2 is a plan view, and FIG. 3 is a sectional view showing a vertical movement mechanism. 10... Vertical movement device 11... Cylinder 12.
... Piston 20 ... Moving device 21 ... Fixed frame 22 ... Guide shaft 30 ... Vertical movement frame 31 ... Slide shaft 32 ... Fixed body 40 ... Driver frame 41 ... Air driver 42... Driver spring 43... Driver head 50... Finger mechanism, 51... Finger frame 52... Finger spring 53... Mechanical finger

Claims (1)

[Claims] 1. A vertically moving frame that can be moved up and down by a vertically moving mechanism is provided on the guide shaft provided on a fixed frame fixed to the moving mechanism, and the slide shaft is fixed to this vertically moving frame, and the driver frame and finger frame are connected by springs. The driver frame is equipped with an air driver, the finger frame is equipped with a finger mechanism for grasping screws, and the driver head at the tip of the air driver An automatic screw tightening device characterized in that the finger mechanism is formed so as to protrude downward from the lower end in a normal state.