JPH0871939A - Screw holding device - Google Patents

Abstract

PURPOSE: To improve the handling of a screw by composing a screw attaching power tool so that various kinds of screw having different shapes may be held, and the various screws may be easily screwed into a spot where a finger can not reach, and the screw may be easily set. CONSTITUTION: An inner and an outer cylinder 5, 7 are slidably inserted into an engaging shaft 1 which is connected to the driving shaft of a power tool and has a desired bit 4 being attach-detachable at its tip, and at least three pieces of elastic holding pieces 6 having tip directions bent in about mountain- shape are attached to the above cylinders 5, 7 so as to mutually expand at their tips. An opened tip cylinder-shaped cover 6 to cover the circumference of the elastic holding piece 6 and the bit 4 is attached to the outer cylinder 7, and a screw holding part 3 is formed of these components, and pressed in a direction protruding from an engaging shaft 1 by an energizing means 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw holding device which is used by being attached to an electric power tool and which enables tightening of a screw in a place where a hand or a finger cannot reach.

[0002]

2. Description of the Related Art Conventionally, as this type of screw holding device,
There were those disclosed in Japanese Utility Model Laid-Open No. 4-51373 and JP-A-56-119381.

The device of Japanese Utility Model Laid-Open No. 4-51373 described above uses the bits 11, 1 of the electric screwdriver as shown in FIGS. 8 and 9.
4 has magnetic rings 12 and 15 attached to the tips thereof, and when used, a flat head screw 13 or a round head screw 16 is attached to the tips of the bits 11 and 14 as shown in FIG. It was designed to be adsorbed and held at 12 and 15.

Further, as shown in FIG. 10, the apparatus of the above-mentioned Japanese Patent Laid-Open No. 56-119381 is capable of advancing and retreating with a screw holding engaging member 17 having a front end edge and a rear end edge as inclined surfaces facing the inside of the cylinder. And a plurality of slits parallel to the central axis in the front half of the cylindrical body through which the tightening shaft 19 can be inserted and the screw holding portion 18 formed by providing an inward projecting edge 18a on the inner peripheral surface of the rear end. A projecting edge 20a that engages with the inward projecting edge 18a to allow the tubular body to clamp the shaft 19 between
And a member 23 that urges the tightening shaft insertion portion 20 in the direction in which the tightening shaft insertion portion 20 is removed from the screw holding portion 18.

This device is used by being attached to a tightening shaft 19 such as a ratchet driver, and its function is that an engaging member 17 provided in the cylinder so as to be able to move forward and backward comes into contact with a neck portion 21a of a screw 21. The screw 21 is held in a rotatable state by a driver. This function will be described in detail. First, the screw 21 is attached to the tip opening portion 1 of the screw holding portion 18.
By press-fitting from 8b, it is held by the engaging member 17 and the preparation is completed. Then, in this state, the tip of the screw 21 is applied to the substrate 22 which is the object to be attached, and when the screw 21 is tightened, the holding device moves to the substrate 22 side as the screw 21 is tightened, and eventually the tip of the screw holding portion 18 is reached. Contacts the substrate 22. Then, when tightening is further performed from this state, the screw holding portion 18 in contact with the substrate 22 is pressed against the base end side of the tightening shaft 19, and the urging member 2 is pressed.
It moves to the base end side of the tightening shaft insertion portion 20 against 3. As a result, the projecting edges 18a, 20a of the screw holding portion 18 and the tightening shaft inserting portion 20 are separated from each other and the hole is expanded, so that the tightening shaft inserting portion 20 moves to the base end side of the tightening shaft 19, and the result As a holding device for tightening shaft 19
It will retreat relatively to. As a result, the engaging member 17 holding the neck portion 21a of the screw 21 is also retracted, and eventually the engaging member 17 is released from the screw 21.
The head 21b of the vehicle is overcome and the engagement is released. Therefore, after that, the screw 21 is tightened by rotating the tightening shaft 19 like the usual screw tightening, and after the work is completed, the ratchet driver or the like is simply pulled. It was to be removed from the tightening part of.

[0006]

In the above-mentioned conventional screw holding device, the one shown in Japanese Utility Model Laid-Open No. 4-51373 is designed to hold the screw by utilizing the attractive force of the magnet. However, there is a possibility that other things may be attracted, or the magnet may be attracted to the surroundings in a small space, and there is a problem that the handling is not necessarily excellent. Further, in this device, since the head of the screw is adsorbed and held from one side, if the shape of the head of the screw is different, the holding is incomplete and wobbles or falls off. In order to prevent this, as shown in FIGS. 8 and 9, the flat head screw 13 or the round head screw 1
The magnetic rings 12 and 1 each having a corresponding shape according to 6
There was a problem that I had to prepare 5.

Further, in the device disclosed in Japanese Patent Laid-Open No. 56-119381, the engaging member is used to hold the screw only in the initial stage of screwing, and therefore, there is a problem such as the one using the magnet described above. However, after tightening the screws, the screw holders must be pulled one by one to restore the device to the original state where the screws can be held, resulting in poor handling and positioning because there is no stopper etc. However, there is a problem in that the operability is poor and the operability is poor.

An object of the present invention is to solve the problems that these conventional screw holding devices have.

[0009]

According to the present invention, an engaging shaft having a bit removably attached to its tip, and at least three elastic holding pieces slidably attached to the engaging shaft and not deviating from the engaging shaft are provided. The ends of the elastic holding pieces are arranged so as to spread apart, and the periphery of the elastic holding piece is covered with a cylindrical cover with an open end, and the holding portion is attached in the direction of the tip of the engaging shaft. The above-mentioned conventional problem is solved by using a screw holding device including a biasing means for biasing.

[0010]

The at least three elastic holding pieces attached to the holding portion press the peripheral portion of the screw under pressure to engage the screw with the bit and hold the screw in a state capable of tightening.

Further, the cover for covering the elastic holding piece prevents an accidental accident due to the elastic holding piece coming into contact with the periphery of the screw mounting portion at the time of working, and makes contact with the surface of the screw mounting portion as the screw is screwed. Then, the holding portion urged in the protruding direction by the urging means is moved backward so that the elastic holding piece pressing the neck portion of the screw is moved backward so as not to hinder screwing of the screw.

Further, the urging means for urging the holding portion toward the tip of the bit does not prevent the holding portion from retreating due to screwing of the screw, and after the work is completed, the holding portion is in the original state in which the screw can be held. It acts to return to.

[0013]

1 is a half sectional view showing an embodiment of the present invention, and FIG. 2 is a side view in an exploded state. As shown in the drawing, the screw holding device of the present invention includes a bit 4 that is detachably attached to a screw, and an engagement shaft 1 that is connected to a drive shaft (not shown) of an electric tool such as an electric screwdriver. It is composed of a screw holding portion 3 slidably attached to the engaging shaft 1 and a biasing means 2 such as a coil spring for biasing the holding portion 3 toward the tip of the bit 4.

The holding portion 3 is attached to the elastic holding piece 6 whose end portion is bent in a substantially V shape, the inner cylinder 5 and the outer cylinder 7 for fixedly holding the elastic holding piece 6, and the outer cylinder 7. ,
The bit 4 and the elastic holding piece 6 are covered with a cylindrical cover 8 with an open tip.

As shown in FIGS. 3 and 4, the inner cylinder 5 is formed with a groove 52a in the front-rear direction into which the rear portion 6c of the elastic holding piece 6 is fitted at equiangular positions (at least three places) on the periphery. A main body 52 in which a locking portion 52b into which the rear end bent portion 6a of the elastic holding piece 6 is fitted is formed at one end of the groove 52a, and the main body 52 is fitted to close the outside of the locking portion 52b. , Fitting member 51. This main body 5
It is assumed that the inner diameters of both 2 and the fitting member 51 are substantially the same as the outer diameter of the engaging shaft 1.

The outer cylinder 7 has an inner diameter of the inner cylinder 5
Is formed to have almost the same diameter as the outer diameter.

The inner and outer cylinders 5 and 7 and the cover 8 are
May be made of any material such as plastic or metal, but if it is made of a synthetic resin material, it is desirable because it is easy to mold and can be manufactured at low cost, and the cover is used. 8 can be formed transparently, and in this case, the operation for holding the screw can be performed while visually recognizing it from the outside, which is more desirable.

The elastic holding piece 6 may be a round spring or a leaf spring, and the material thereof may be steel, stainless steel, synthetic resin, or the like.

It should be noted that at least three elastic holding pieces 6 are required so as to be in contact with the periphery of the neck of the screw and hold the screw immovably.

The screw holding device of the present invention constituted by the above members is assembled as follows.

First, the main body 52 of the inner cylinder 5 and the fitting member 51 are integrally joined using a means such as an adhesive or ultrasonic welding to form the inner cylinder 5. Next, the elastic holding pieces 6 are respectively inserted into the plurality of grooves 52a formed around the inner cylinder 5.
A plurality of elastic holding pieces 6 are attached by fitting the rear portion 6c and inserting the rear end bent portion 6a of the elastic locking piece 6 into the locking portion 52b. After that, the outer cylinder 7 is fitted into the inner cylinder 5 and both are integrally joined. As a result, the elastic holding pieces 6 are held with their tips facing each other inside the outer cylinder 7.

Next, the inner cylinder 5 is inserted and attached from the front end side of the engagement shaft 1 with the biasing means 2 such as a coil spring interposed, and attached to the front end of the engagement shaft 1 protruding from the front end of the inner cylinder 5. Attach the retaining ring 9. Then, the cover 8 is integrally attached near the tip of the outer cylinder 7 to complete the assembly.

The cover 8 is attached at the final stage of assembly so that the retaining ring 9 can be easily attached to the engagement shaft 1, but it may be integrally joined to the outer cylinder 7 in advance. good.

Next, the operation of the screw holding device of the present invention having the above-mentioned structure will be described. First, the opening of the cover 8 of the screw holding device connected to the drive shaft of the electric tool and having the bit 4 corresponding to the tip attached thereto. When the head 10b of the screw 10 is press-fitted from the screw 8a, the elastic holding piece 6 is bent outward so that the head 10b rides over the V-shaped bent portion 6b and is inserted to a position where it engages with the bit 4. In this state, the elastic holding piece 6 is restored by its own elastic force and is pressed against the periphery of the neck 10a of the screw 10 to hold the screw 10 in a retaining shape as shown in FIG.

In this way, first, the screw tightening is prepared.

Then, in this state, when the drive shaft of the electric tool is driven by applying it to the mounting portion W such as a wall or ceiling where the tip of the screw 10 is mounted, the engagement shaft 1 connected to this drive shaft is driven. The screw 10 held at the tip of the bit 4 is rotated through and is screwed into the mounting portion W. In this way, screwing of the screw 10 is started, and the holding device of the screw 10 initially moves in the mounting portion W direction (rightward in FIG. 5) together with the screw 10 as the screw 10 is screwed.

When the tip of the cover 8 comes into contact with the surface of the mounting portion W and is further screwed in this state, the holding portion 3 slidably attached to the engaging shaft 1 is attached as shown in FIG. It moves to the base end side of the engagement shaft 1 against the biasing force of the biasing means 2. Therefore, the elastic holding piece 6 attached to the holding portion 3
Is also retracted, and the engagement with the neck portion 10a of the screw 10 is released. At this time, since the tip of the screw 10 has already been screwed into the mounting portion W to some extent, wobbling does not occur even if the screw 10 is not held.

Then, when the drive shaft is further rotated from this state and screwing is continued, the screw 10 will eventually move to the position shown in FIG.
As shown in, the screw is completely screwed into the mounting portion W, and the mounting of the screw 10 is completed. At this time, since the holding portion 3 moves to the base end side (left side in the drawing) of the engagement shaft 1 against the urging force of the urging means 2, the screwing operation of the screw 10 is not hindered. .

After the screw fastening work is completed in this way, when the tool is pulled away from the mounting portion W together with the holding device, the holding portion 3 urged by the urging means 2 such as a coil spring causes the engaging shaft 1 to move. The inner cylinder 5 moves to the tip side and the retaining ring 9
It returns to the original position where it abuts. Therefore, as described above, the head 10b of the screw 10 is attached to the tip opening 8a of the cover 8.
Since the screw 10 can be held by press-fitting from above, the screw 10 can be screwed in the same manner as described above.

Thus, in the screw holding device of the present invention, the screw 10 is simply press-fitted from the tip side of the holding device,
The set can be done and the screwing work can be repeated.

In the present embodiment, the inner cylinder 5 is joined to the main body 52 and the fitting member 5 joined to the main body 52 for easy manufacture.
However, the inner cylinder 5 may be integrally formed as long as it can immobilize the rear portion 6c of the elastic holding piece 6 immovably.

[0032]

As described above, in the screw holding device of the present invention, the screw can be attached using an electric tool without holding the screw with fingers, so that it can be used in high places and narrow places where the fingers cannot reach. Work can be done efficiently. Further, at this time, since no magnet is used to hold the screw, there is no possibility that other objects will be attracted or attracted to the surroundings, and the work will be easy. In addition, the screw can be set by simply pressing the head of the screw from the tip side of the device, and after the work is completed, the device returns to the state where the screw can be set, which is excellent in handleability and operability. .

Further, since the screw holding device of the present invention is capable of exchanging bits, it has many excellent effects of being able to cope with work using different types of screws such as flat-head screws and round-head screws with one unit. .

[Brief description of drawings]

FIG. 1 is a half sectional view of the present invention and an embodiment.

FIG. 2 is an exploded view of an example.

FIG. 3 is a half sectional view of the inner cylinder shown in the embodiment.

FIG. 4 is a front view of the inner cylinder shown in the embodiment.

FIG. 5 is a half sectional view showing a state at the start of work.

FIG. 6 is a half sectional view showing a state during work.

FIG. 7 is a half cross-sectional view showing a state when the work is completed.

FIG. 8 is a cross-sectional view of essential parts showing an example of a conventional example.

FIG. 9 is a sectional view of an essential part showing another embodiment of the conventional example.

FIG. 10 is a half sectional view of another conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Engagement shaft 2 Energizing means 3 Holding part 5 Inner cylinder 6 Elastic holding piece 7 Outer cylinder 8 Cover 9 Lock ring

Claims (1)

[Claims] 1. An engagement shaft to which a bit is detachably attached at the tip, and a direction in which at least three elastic holding pieces are attached to the engagement shaft so as to be slidable and non-detachable, and the tips of the elastic holding pieces expand. And a holding portion of a screw whose periphery is surrounded by a cylindrical cover with an open tip, and a biasing means for biasing the holding portion toward the tip of the engaging shaft. A screw holding device characterized in that