JPS5831641Y2 - screw tightening device - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a screw tightening device that clamps and unclamps a screw component such as a bolt by utilizing forward and reverse rotation of a drive shaft that tightens the screw component.

Generally, a device is used that clamps a threaded part such as a bolt supplied at a supply position, transfers it to a predetermined screw tightening position, and tightens the threaded part with a nut runner at this position. In this case, means for clamping the threaded part and means for tightening the threaded part are provided separately, or the clamping and unclamping of the threaded part is performed using vertical movement of the unit.

However, the former method requires a large and expensive device, while the latter method has a complicated structure and has the problem of not being able to operate the ramp reliably if the diameter of the threaded part to be clamped is changed. Ta.

This invention solves the above-mentioned problems by clamping and unclamping threaded parts using the forward and reverse rotation of the drive shaft that tightens the threaded parts, simplifying the structure and shortening the cycle time. Another object of the present invention is to provide a screw tightening device that can reliably tighten even if the diameter of a threaded part such as a bolt changes.

An embodiment of this invention will be described below with reference to the drawings.

In FIG. 1, 1 is a screw tightening body, and this screw tightening body 1 is installed on an elevating body (not shown) and reciprocates with the elevating body between a bolt supply position and a screw tightening position. There is.

A drive shaft 2 that is rotated forward and backward by a motor (not shown) is rotatably supported on the screw tightening body 1.
The upper end of the holder 3 is screwed and fixed to the lower end of the holder.

A rotational force transmitting member 4 is keyed and fitted to the lower end of the drive shaft 2 protruding into the holder 3, and a connecting cylinder 5 is fixed to the transmitting member 4 with screws.

As shown in FIG. 2, an outer sleeve 6 is fitted into the connecting cylinder 5 with a pin, and an inner sleeve 7
Both upper and lower ends are rotatably supported via bearings.

Concave grooves 6a are formed on the inner circumferential surface of the outer sleeve 6 at multiple locations in the circumferential direction at equal angular intervals.
There are protrusions 7 at equal angular intervals at multiple locations in the circumferential direction on the outer peripheral surface of the
a are formed, and these protrusions 7a are fitted into the grooves 6a of the outer sleeve 6, and the outer sleeve 6 is held within a predetermined angle range.
and the inner sleeve I are configured to be relatively rotatable.

A shaft 8 is spline-fitted to the inner sleeve 7 so as to be movable in the axial direction, and a spring 9 is interposed between a collar 8a provided on the shaft 8 and the lower end surface of the inner sleeve 7. For tightening, the shaft 8 is urged downward, and for tightening, a regulating plate 10 screwed and fixed to the upper end of the shaft 8 is pressed against the upper end surface of the inner sleeve 7.

For tightening, a driver 11 is pinned and replaceably fitted to the tip of the shaft 8, and a hooked projection 11a is formed at the tip of the driver 11 protruding from the lower end of the holder 3. is configured to have a shape and one dimension that removably engages with the square hole 12b of the head 12a of the bolt 12.

Further, a transmission sleeve 14 is rotatably fitted to the drive shaft 2 via a one-way rotation clutch 13, and the one-way rotation clutch 13 transmits the 20 rotations of the drive shaft to the transmission sleeve 14 only when the drive shaft 2 is reversed. It is like that.

A drive gear 15 that is concentric with the drive shaft 2 is fixed to the transmission sleeve 14, and three driven gears 16 that mesh with the drive gear 15 are fitted onto the upper end of the operating shaft 17 with keys.

The operating shaft 17 is the drive shaft 2. The tightening mechanism is arranged around the shaft 8 at equal angular intervals on the outside thereof, and is rotatably supported by end plates 18 fixed to the upper end of the holder 3 and the lower end of the holder 3. Ru.

Figure 1. As shown in FIG. 3, the clamp mechanism 19 has a rotary body 2 attached to the lower end of the operating shaft 17 protruding from the end plate 18.
0 is fixed, and clamp arms 21 located below the rotating body 20 are respectively rotatably fitted.

A notched groove 20 is formed in a part of the outer circumference of the rotating body 20 in the circumferential direction.
A is formed in the cutout groove 20a, and a stopper shaft 22 protruding downward from the end plate 18 is fitted into the cutout groove 20a to restrict the rotation of the rotating body 20 to a predetermined angle.

The spring hook protruding below the end plate 18 is connected to the pin 23 and the rotating body 2.
An unclamping spring 25 is installed between the arm stopper pin 24 and the arm stopper pin 24 set at 0, and the rotating body 20 is biased clockwise in FIG. 3, respectively.

A clamp roller 27 is rotatably supported by a pivot shaft 26 on the lower surface of the tip of the clamp arm 21, and a clamp spring 29 is installed between a pin 28 and the pivot shaft 26 in the spring hook provided on the rotating body 20. , clamp arm 21
is biased in the counterclockwise direction in FIG. In this state, the clamp roller 27 is in an unclamped state.

Next, the operation of the screw tightening device configured as above will be explained.

When the screw tightening body 1, which is in the bolt supply position, is lowered to a predetermined position in the unclamped state shown in FIGS. The driver 11 is engaged with the hole 12b, and the driver 11 comes into contact with the head 12a of the bolt 12, and the tightening operation is performed by compressing the spring 9 together with the shaft 8 and moving up relative to the inner sleeve 7, and the head of the bolt 12 is tightened. The portion 12a is located between the clamp rollers 27, and the screw fastening body 1 reaches the lower end.

In this state, when the drive shaft 2 is started in the reverse direction (clockwise in FIG. 2), the one-way rotation clutch 13. Transmission sleeve 14
．． Drive gear 15. The operating shaft 17 rotates via the driven gear 16, and the rotating body 20 and clamp arm 21 of the clamp mechanism 19 rotate counterclockwise in FIG. 3 against the spring force of the unclamping spring 25. Clamp roller 2 provided on clamp arm 21 as shown in FIGS. 4 and 5
7 clamps the head 12a of the bolt 12.

That is, by rotating the rotating body 200 counterclockwise, the contact between the distal end of the clamp arm 21 and the arm stopper pin 24 is released, so that the clamp arm 21 moves in the opposite direction as shown in FIG. The clamp roller 27 is biased clockwise and elastically holds the head 12a of the bolt 12.

Further, due to the reverse rotation of the drive shaft 2, the rotational force transmission member 4. Although the connecting cylinder 5 and the outer sleeve 6 are reversed, the amount of rotation of the outer sleeve 60 is small and the protrusion 7a of the inner sleeve 7 is in the groove 6a, so the inner sleeve 7
, the tightening shaft 8 and driver 11 are not reversed.

In the clamped state described above, the screw tightening body 1 is raised and shifted laterally to the screw tightening position.

At this screw tightening position, the screw tightening body 1 is lowered to a predetermined position so that the threaded portion of the clamped bolt 12 corresponds to the screw hole into which it is screwed.

When the drive shaft 2 is started to rotate forward (counterclockwise in FIG. 2) at the descending end of the screw tightening body 1, the - direction rotation clutch 13 causes the rotating body 20 to rotate clockwise in FIG. 5 by the spring force of the unclamping spring 25. Rotation in the direction is allowed, and these rotation bodies 20
3, the clamp arm 21 is rotated by the arm stopper pin 24 against the spring force of the clamp spring 29, and the clamp roller 27 unclamps the head 12a of the bolt 12 as shown in FIG.

In this case, due to normal rotation of the drive shaft 2, the outer sleeve 6
Even if it rotates in the normal direction, the outer sleeve 6 does not engage with the inner sleeve 7 until it is in the unclamped state.

After the above-mentioned unclamping operation is completed, the outer sleeve 6 engages with the inner sleeve 7, and forward rotational driving force is transmitted from the drive shaft 2 to the driver 11 through the sleeves 6.7, and the bolt 12 is rotated. Tighten the screws.

In this case, the one-way rotation clutch 13 slips, and the transmission sleeve 14 does not rotate. Therefore, the operating shaft 17 and the clamp mechanism 19 do not operate and remain in an unclamped state.

After the bolt 12 has been tightened, the screw tightening body 1 is raised, the normal rotation of the drive shaft 2 is stopped, the screw tightening body 1 is returned to the bolt supply position, and the above-described operations are repeated. It is something.

As explained above, the screw tightening device of this invention has a screw tightening body 1 that reciprocates between the supply position of screw parts such as bolts and the screw tightening position, and a drive shaft 2 that can move forward and backward.
The drive shaft 2 is provided with play in the rotational direction of the unclamping and clamping operation range due to forward and reverse rotation, and the driver 11 is connected to the drive shaft 2.
The rotary bodies 20 are fitted and fixed to a plurality of actuating shafts 1T to which rotational force is transmitted only in the reverse direction through the rotary bodies 3, and the unclamp springs 25 are connected to these rotary bodies 20. A rotatable lamp arm 21 equipped with a clamp body such as a clamp roller 27 for clamping a threaded part is connected to the drive shaft via a clamp spring 29 that biases the lamp arm 21 in the clamping direction. The rotation of the rotary body 20 due to the reverse rotation of the drive shaft 2 causes the clamp body provided on the clamp arm 21 to elastically hold and clamp the screw component, and the forward rotation of the drive shaft 2 unclamps the screw component.

Therefore, according to this invention, clamping of threaded parts such as bolts.

Since unclamping is performed using forward and reverse rotation of the drive shaft that tightens the screw parts, the configuration is simple, and screw tightening can be performed following unclamping by forward rotation of the drive shaft. In addition, the clamp body can rotate in a direction perpendicular to the axial direction of the drive shaft and the driver, that is, in a substantially horizontal direction, to clamp and unclamp the threaded parts, and the spring force of the clamp spring can reduce the cycle time. Since clamping is performed using a clamp body, it is possible to reliably perform ramping even if the diameter of the threaded part changes.

[Brief explanation of the drawing]

Fig. 1 is a partially vertical side view showing an embodiment of this invention in an unclamped state, Fig. 2 is a sectional view taken along the line ■-■ in Fig. 1, and Fig. 3 is a cross-sectional view taken along the line -■ in Fig. 1. A bottom view as seen from the arrows, and FIG. 4 is a side view of a portion of the clamp mechanism in a clamped state.
FIG. 5 is a bottom view of the same. 1... Screw tightening body, 2... Drive shaft,
11... Driver, 12... Volt (
threaded parts), 13... one-way rotation clutch, 1
7... Operating axis, 20... Rotating body, 21...
... Clamp arm, 25 ... Unclamp spring, 27 ... Clamp roller (clamp body), 29 ... Clamp spring.

Claims (1)

[Scope of utility model registration request] A screw tightening body that moves reciprocally between a supply position of screw parts and a screw tightening position and moves up and down is equipped with a drive shaft that can be rotated in the forward and reverse directions, Clamp, clamp operation range Q is provided in the rotational direction to connect the driver, and the rotating bodies are respectively fitted and fixed to a plurality of operating shafts to which rotational force is transmitted only in the reverse direction from the drive shaft via a one-way rotation clutch. An unclamping spring is connected to these rotating bodies, and the rotating body is equipped with a clamping body located on the outer periphery of the lower end of the driver to clamp the threaded parts, and the rotatable lamp arm is biased in the clamping direction. The screw parts are connected via a clamp spring, and the screw parts are elastically clamped by the clamp body provided on the clamp arm by the rotation of the rotary body due to the reversal of the drive shaft, and unclamped by the forward rotation of the rotary body. A screw tightening device characterized by: