JP2603768Y2 - Installation tools for driving screws - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction tool in which a driving screw is first driven into a work material, and then the driving screw is driven.

[0002]

2. Description of the Related Art In general, a driving screw is further screwed after being driven into a material to be processed, and has a feature that combines the speed of nail workability and the difficulty of screw removal. The installation tool is used to strike the driving screw supplied from the magazine into the injection section with a driver bit, and drive the driving screw to such an extent that the head of the driving screw floats from the surface of the work piece. , And the driving screw is screwed in.

[0003]

However, in a conventional driving tool for driving screws, when the driving screw is rotated after hitting, the driver bit is rotatably supported by the hitting piston and moves in the driving direction. Since the driving screw does not rotate, the driving screw is screwed only by rotation, and the head of the driving screw is separated from the tip of the driver bit as the screw is driven, so that the tip of the driver bit disengages from the head of the driving screw. Easy to do.

An object of the present invention is to solve the above-mentioned problem and to provide a driving screw working tool which can press the driven screw further in the screwing direction after hitting the driven screw with a driver bit. And

[0005]

In order to solve the above-mentioned problems, a driving tool for a driving screw according to the present invention drives a striking piston, which is slidably accommodated in a striking cylinder, downward by compressed air. in driving construction tool screws screwed by rotating the drive screw in the object construction material of the driver bit after forme a drive screw striking the driver bit provided in the striking piston, the driver bit, through of the striking piston Driver bit base
The end is exposed in the striking cylinder and the striking piston is
Relative to the driving direction.
And location, the striking piston further slid downward the driver bit by compressed air which is driven at the bottom dead center position it was possible pushed further screwing direction drive screw which is struck by the driver bit at the striking ends It is characterized by.

[0006]

According to the present invention, when the striking piston is driven by the compressed air at the time of striking, the driver bit strikes the driving screw and strikes the workpiece. At this time,
The driver bit is mounted through the striking piston
Therefore, the area receiving the air pressure of the compressed air is small.
So that the driving screw floats from the workpiece
Drive in. At the end of the impact, the impact piston is
Although the drive bit reaches the dead center position, the driver bit can be slid further downward by the compressed air that drives the impact piston, and the driving screw hit by the driver bit can be further pressed in the screwing direction. Is hard to come off the head of the driving screw.
As described above, the engagement between the driver bit and the driving screw is ensured even after the impact, so that the screwing operation after the impact can be easily and reliably performed. Similarly, even if the construction tool bounces due to the recoil at the time of impact, the driver bit slides further downward by the compressed air, so that the recoil is absorbed and the engagement between the driver bit and the driving screw is ensured.

Further, since the driver bit is attached so as to penetrate the striking piston, the area receiving the compressed air pressure is small. For this reason, since the pressing force for pressing the driving screw in the screwing direction is also weak, it is possible to reduce the recoil for lifting the driver bit upward during screwing.

Further, since the driver bit is mounted so as to penetrate the striking piston, the structure is simple and the number of parts is small.

[0009]

FIG. 1 shows a vertical section of a main part of a driving tool for a driving screw. A tool body 1 has a striking cylinder 3 in which a striking piston 2 is slidably accommodated, and one end of the striking cylinder 3. And a driver bit 5 supported by the striking piston 2 and guided into the injection portion 4, and a holding portion for holding the driver bit 5 inside the injection portion 4. A sleeve 6 is arranged, and a piston / cylinder mechanism 10 for driving a holding sleeve is arranged above a magazine 8 for supplying a driving screw 7 to the injection section 4. In this example, the driving screw 7 used for the tool main body 1 has a cross-shaped engaging groove 7a formed on the head surface and a circular peripheral surface.

A striking mechanism is constituted by the striking cylinder 3 and the striking piston 2, and the striking mechanism operates a striking drive mechanism (not shown) by driving a trigger lever 11 to drive compressed air from a compressed air supply source P (not shown). The compressed air in the main air chamber 12 formed in the tool main body 1 is supplied to the striking cylinder 3 based on the actuation operation of the striking cylinder 1 to drive the striking piston 2 to strike the driver bit 5. The compressed air compressed at the time of the striking operation of the striking piston 2 is stored in the blowback chamber 13, and the striking piston 2 at the bottom dead center position is returned to the top dead center using this compressed air. The drive mechanism is the same as that of a known pneumatic nailer. When the striking piston 2 is at the bottom dead center where it contacts the damper 9, the tip of the driver bit 5 is formed to protrude from the injection section 4.

The base end of the driver bit 5 is the striking piston 2
, And the tip is slidably guided into the injection section 4. In addition, a driving screw 7
And a cross-shaped engaging portion 5a that engages with the head engaging groove 7a.

The holding sleeve 6 is rotatably supported inside the injection section 4, and the driver bit 5 is mounted on the holding sleeve 6.
Is held inside. The shape of the inner surface of the holding sleeve 6 is substantially the same as the shape of the outer surface of the driver bit 5 (for example, a polygon), so that the holding sleeve 6 rotates with the driver bit 5 over the entire sliding stroke of the driver bit 5. It is formed integrally and so as to allow sliding.

The magazine 8 accommodates the driving screw 7 and is sequentially supplied to the ejection unit 4 by a supply mechanism (not shown). The driving screw 7 is connected to the injection section 4 by an appropriate means.
In this case, the supply is made such that the engagement groove 7a of the head always faces in the same direction, that is, the direction in which it is aligned with the engagement portion 5a at the tip of the driver bit 5.

A piston / cylinder mechanism 10 for driving the holding sleeve is disposed above the magazine 8 and near the injection unit 4, and the driving piston 14 is reciprocated during a predetermined stroke. The rear end of the drive cylinder 15 is connected to the main chamber 12 via a three-way valve 22.
5, compressed air is supplied to the rear end,
The rear end is connected to the exhaust port. 3 above
The directional valve 22 is connected by an air passage 16 so as to be operated by the air pressure supplied from the blowback chamber 13, and a speed controller 22 a (throttle adjusting device for the air passage) is interposed in the passage 16. Thus, the operation timing of the drive cylinder 15 can be adjusted. In addition, the holding sleeve driving piston / cylinder mechanism 10 and the holding sleeve 6 are linked via a conversion mechanism 17 that converts the reciprocating operation of the holding sleeve driving piston / cylinder mechanism 10 into a rotational movement of the holding sleeve 6. . The conversion mechanism 17 is formed by meshing a gear 18 fixed to the outside of the holding sleeve 6 with a rack 19a of a rack member 19 integrally connected to the driving piston 14.

In the above-described configuration, when the trigger lever 11 is operated, the striking mechanism operates, and the striking piston 2 is driven into striking as shown in FIG. At this time, the tip engaging portion 5 of the driver bit 5
Since a is aligned with the head engaging groove 7a of the driving screw 7, the hit does not damage the head engaging groove 7a. Then, the impact piston 2 is moved down by the impact, and the driver bit 5 slides along the inner surface of the holding sleeve 6 to strike out the driving screw 7 and to project from the tip of the injection unit 4. In this state, the head of the driving screw 7 is still floating from the surface of the workpiece. Subsequently, a part of the compressed air stored in the blowback chamber 13 at the time of impact operates the three-way valve 22 through the air passage 16. By operating the three-way valve 22, the compressed air in the main chamber 12 is supplied to the rear end of the driving cylinder 15 of the holding sleeve driving piston / cylinder mechanism 10, and the driving piston 14 is pushed out by the compressed air, so that the rack member 19 moves forward. Then, the holding sleeve 6 rotates together with the gear engaged with the rack 19a, and the rotation causes the driver bit 5 to rotate integrally.
Since the tip engaging portion 5a of the driver bit 5 and the head engaging groove 7a of the driving screw 7 are engaged with each other, the driving screw 7 is also rotated by the rotation of the driver bit 5, and is screwed into the workpiece. The driving is completed. Thereafter, when the operation of the trigger lever 11 is released, the striking piston 2 is returned by the remaining compressed air in the blowback chamber 13, and the driving piston 14 of the piston / cylinder mechanism 10 for holding sleeve driving is also returned by the spring. I do. With the drive piston 14 stopped at the return movement end,
Again, the engaging portion 5a of the driver bit 5 is in the same direction as before the operation, and the next driving is prepared.

As described above, since the direction of the engaging portion 5a of the driver bit 5 is always constant at each time of hitting, the direction of the engaging groove 7a of the head of the driving screw 7 supplied into the injection portion 4 is changed. If they are made to correspond to the engaging portions 5a of the driver bit 5, they are always engaged at the time of hitting.

Next, the driver bit is disposed so as to be movable in the driving direction relative to the striking piston 2. That is, as shown in FIGS. 3 and 4, the driver bit 5 is inserted into the through hole 2 a at the center of the striking piston 2. Also, a collar 2 is provided at the base end of the driver bit 5.
3, the flange 23 is fitted in a recess 24 formed in the upper part of the striking piston 2, and the flange 23
A compression spring 25 is interposed between and the upper bottom surface of the recess 24.

According to the above configuration, when the striking piston 2 is driven by the compressed air at the time of striking, the driver bit 5 strikes the striking screw 7 to strike the work material, and the striking piston 2 comes into contact with the damper 9. Reach bottom dead center. The construction tool instantaneously bounces upward due to the recoil of the driving. However, at the end of the impact, the flange 23 of the driver bit 5 is pressed by the air pressure of the compressed air that drives the impact piston 2 to the bottom dead center position, so that the driver bit 5 slides further downward and is impacted. Since the driven screw 7 can be further pressed in the screwing direction, the tip of the driver bit 5 is hard to come off the head of the driven screw 7. Therefore, the tip of the driver bit 5 is set so as not to protrude from the tip of the injection part 4 when the striking piston 2 reaches the bottom dead center at the time of impact, and is set to protrude from the tip of the injection part 4 at the end of the screwing operation. In addition, since the engagement between the driver bit 5 and the head engaging groove 7a of the driving screw 7 is ensured even after the impact, the screwing operation after the impact can be easily and reliably performed. Similarly, even if the construction tool bounces due to the recoil at the time of impact, the driver bit 5 slides further downward by the compressed air, so that the recoil is absorbed and the engagement between the driver bit 5 and the driving screw 7 is secured. Is done.

After the screwing operation is completed ,
By releasing the operation of the trigger lever 11 as shown in FIG.
-The compressed air in the back chamber 13 is exhaust port 13a
And acts on the lower surface of the striking piston 2,
The impact piston 2 is in its original position with the driver bit 5
(The position shown in FIG. 3).

The driver bit 5 is used for the striking piston 2
, The area receiving the air pressure of the compressed air is small. For this reason, since the pressing force for pressing the driving screw 7 in the screwing direction is also weak, it is possible to reduce the recoil for lifting the driver bit 5 upward during screwing.

Further, since the driver bit 5 is mounted so as to penetrate the striking piston 2, the structure is simple and the number of parts is small.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a driving screw installation tool according to the present invention.

FIG. 2 is an operation explanatory view of the construction tool.

FIG. 3 is an explanatory view of a mechanism for relatively moving a striking piston and a driver bit.

FIG. 4 is an operation explanatory view of the mechanism of FIG. 3;

[Explanation of symbols]

 2 Impact Piston 3 Impact Cylinder 4 Injection Portion 5 Driver Bit 5a Engagement Portion 6 Holding Sleeve 7 Driving Screw 7a Engagement Groove

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B25B 21/00

Claims (1)

(57) [Scope of request for utility model registration] 1. A blow slide in the cylinder freely housed striking piston said screw driving driver bit provided in the striking piston is driven downward by the compressed air after I struck <br/> driver rotate the bit in driving construction tool screws screwed into the drive screw to said object construction material, the driver bit, by penetrating the striking piston
Exposing the base end of the driver bit into the impact cylinder
Constant in the driving direction relative to the above-mentioned striking piston
The amount only movably disposed, by the compressed air to the striking piston when hit ends were driven at the bottom dead center position is slid further down the driver bit further to the screwing direction drive screw which is struck by the driver bit An installation tool for driving screws, which can be pressed.