JP3671659B2 - Screwing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a screw tightening machine having a vertical guide for holding a screw when the screw is tightened.
[0002]
[Prior art]
The structure in which the vertical guide is provided below the driver bit and the screw is held is well known in the field of automatic drivers such as Japanese Utility Model Laid-Open No. 57-173962. It is also well known that a vertical guide is provided so that a nail is driven vertically in a nailing machine. Thus, the vertical guide merely holds the screw or nail so that the screw or nail can be screwed or driven perpendicular to the workpiece.
[0003]
In recent years, there has been proposed a screw tightening machine that performs screw tightening by rotating and lowering a driver bit by a drive source including an air motor and an air piston. This screwing machine can be used as a nailer, and has the advantage that it can be screwed with a small thrust. However, the time required for screw tightening is longer than that of the nailing machine, and there is a problem that the screw tightening is finished while the screw is lifted by a reaction generated during the screw tightening.
[0004]
For this reason, a vertical guide is provided at the tip of the driving depth adjusting member mounted on the screw tightener main body so as to be movable up and down, and a stopper is provided to prevent the two guides constituting the vertical guide from opening more than a predetermined angle. A recoil prevention device has been proposed in which a vertical guide prevents the screw tightener body from rising due to recoil.
[0005]
[Problems to be solved by the invention]
It has become possible to improve the screw floating due to the reaction to some extent by the above-mentioned reaction prevention device. However, since the driving depth adjusting member is mounted on the screw tightening machine main body so as to be movable up and down, it is inevitable that a rattling occurs between the driving depth adjusting member and the screw tightening machine main body. As a result, the main body of the screwing machine is raised, and it is almost impossible to completely remove the screw floating. Further, since the stopper is required, there is a drawback that the configuration of the vertical guide is complicated.
[0006]
An object of the present invention is to eliminate the drawbacks of the prior art described above, to prevent the screw tightening machine body from rising due to the reaction, thereby completely preventing screw floating and simplifying the configuration of the vertical guide.
[0007]
[Means for Solving the Problems]
The above object is achieved by attaching a vertical guide constituted by at least two guides biased by a spring so as to come into contact at the lower end to the lower end of the nose portion integrated with the screw tightening machine main body.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
A pressure accumulating chamber 4 communicating with a compressed air intake 35 and an operation valve 30 opened and closed by a trigger lever 33 are provided in a body 5 forming an outer frame of the screw tightening machine main body 1, and an air motor 2 and a planetary gear located above. A bottomed cylindrical rotating body 6 rotated via the device 3 is rotatably supported. A pair of concave portions 10 extending in the axial direction is provided on the inner wall of the rotary body 6, and the rotary body 6 is arranged so that the rotary slide member 7 having a pair of convex portions 8 fitted into the concave portion 10 can move in the axial direction. Is provided inside. A driver bit mounting portion for mounting a driver bit 11 is provided inside the lower portion of the shaft member 9 whose upper end is fixed to the rotary slide member 7, and a piston portion 13 is provided on the outer periphery of the lower end. The piston portion 13 slides in the cylinder 12. To do. A damper plate 15 is provided above the cylinder 12 so as to come into contact with the air blocking surface 14 of the rotary slide member 7 when the rotary slide member 7 is lowered by a predetermined distance, and a vent hole 16 is provided below the damper plate 15. Yes. The air vent 16 communicates with an air inlet (not shown) of the air motor 2 via an air passage (not shown). A well-known return air chamber 20 is formed between the lower portion of the body 5 and the outer periphery of the cylinder 12 in an air nailer or the like.
[0009]
Below the body 5 is a hole through which the screw 18 and the driver bit 11 pass, and a well-known nose portion 36 is provided in an air nailer and the like, and is connected by a connecting band (not shown) and loaded into the magazine 17. A screw feed portion 19 for automatically supplying the connected connecting screw 18 to the nose portion 36 is provided in the vicinity of the nose portion 36. A pair of symmetrical guides 22 whose substantially central portion in the height direction is coupled to the nose portion 36 via the pin 21 is biased by a spring 24 provided between the upper portion and the nose portion 36. The lower part which comprises the guide part is mutually contact | abutted, and these pins 21, the guide 22, and the spring 24 comprise the vertical guide 31 of this invention. The guide portion with which the guide 22 abuts is composed of two vertical surfaces 26 parallel to the axial center and an inclined plane 27 provided below the vertical surface 26, and the inclined flat surface 27 becomes another guide 22 as it goes downward. The gap between the inclined plane 27 and the inclined plane 27 is narrowed. In a state where the lower ends of the symmetrical guides 22 are in contact with each other by the spring 24, the four inclined flat surfaces 27 form a square weight, and the space surrounded by the four vertical surfaces 26 is formed by the screw head 28. The gap is almost in contact. Note that 32 is a known push lever in a nailing machine or the like.
[0010]
The operation of the pneumatic screw tightening machine of the present invention configured as described above will be described below.
The pneumatic screw tightening machine according to the present invention starts driving by operating both the trigger lever 33 and the push lever 32 to actuate the operation valve 30. After the push lever 32 is pressed against a material to be fastened, the trigger is started. Even if the lever 33 is pulled or the push lever 32 is pressed against a material to be fastened while pulling the trigger lever 33, the screw can be tightened.
[0011]
When the compressed air intake 35 is connected to a compressor (not shown), the compressed air flows into the pressure accumulating chamber 4 and the operation valve 30. When the push lever 32 is pressed against a material to be fastened (not shown) and the trigger lever 33 is operated, the compressed air flows into the rotating body 6 via the operation valve 30 and an air passage (not shown), and air pressure is applied to the upper surface of the piston portion 13. In addition, the piston portion 13 is pushed down and compressed air is supplied to the air motor 2 through the vent 16 so that the air motor 2 rotates. The rotation of the air motor 2 is transmitted to the rotating body 6 and the rotating slide member 7 through the planetary gear device 3, and as a result, the piston portion 13 and the driver bit 11 at the lower end of the shaft member 9 rotate simultaneously while descending. The screw 18 below the driver bit 11 is released from the connecting band by the downward rotation of the driver bit 11, and is screwed straight into the material to be fastened. At this time, when the screwing machine main body 1 is lifted by the reaction, as shown in FIG. 3, the screw 18 enters the abutting portion of the guide 22 and the screw heads 28 are supported on the vertical surface 26 at four points. When 1 continues to float, the screw head 28 comes into contact with the inclined plane 27 as shown in FIG. Since the guide 22 is fixed to the body 5 via the nose portion 36 and the inclined plane 27 is formed at an angle that supports the screw head 28 from below, the inclined plane 27 is screwed by the holding force of the vertical guide 31. Abutting on the head 28, the screwing machine main body 1 is prevented from being lifted. Thereafter, when the screw 18 is screwed into the material to be fastened, the vertical guide 31 continues to hold the screw 18, so that the screw tightening machine main body 1 is drawn into the material to be fastened by the screw 18, and the lift is completely removed. To be sealed. When the screw 18 is tightened to a predetermined depth, the rotary slide member 7 abuts against the damper plate 15 and stops descending, and the vent 16 is closed and the air motor 2 is stopped. When the trigger lever 33 is returned, the inflow of compressed air into the rotating body 6 is blocked, and the piston portion 13 returns to the original initial position by the compressed air in the return air chamber 20. 5 and 6 show the relationship between the screw 18 and the guide 22 in the course of screw tightening, and show that the inclined plane 27 is in contact with the screw head 28 regardless of the opening angle of the guide 22.
[0012]
In the above embodiment, the guide 22 is provided with the two vertical surfaces 26 and the inclined plane 27. However, as shown in FIGS. 7 and 8, the guide 22 is provided with one vertical surface 26 and the inclined plane 27. The operational effects are almost the same as in the above embodiment.
[0013]
【The invention's effect】
As described above, according to the present invention, the vertical guide is attached to the screw tightening machine body without looseness, and the screw head is held in contact with the inclined plane of the vertical guide until the screw head is separated from the vertical guide. Even if the vertical guide opens, the contact angle with the inclined plane of the vertical guide that contacts the head and the screw head is always set so that the inclined plane is supported by the inclined plane from below. Even if the machine body is going to rise, the vertical guide holds the screw head firmly, so the reaction can be suppressed and the screw can be securely tightened with a light pressing force. In addition, when the push lever is pressed against the material to be fastened while pulling the trigger lever, the screw tightening machine main body should be perpendicular to the material to be fastened, compared to the case where the push lever is pulled against the material to be fastened beforehand. Although it requires more care when it is pressed, there is no back and forth play between the screw tightening machine body and the vertical guide, so the screw can be tightened stably at the target position. Further, a stopper for preventing the guide from opening more than a predetermined angle is not required, and the configuration of the vertical guide is simplified.
[Brief description of the drawings]
FIG. 1 is a cross-sectional side view showing an embodiment of a screw tightening machine of the present invention.
FIG. 2 is a partially omitted front view showing the vertical guide of FIG. 1;
3 is a plan view of the vertical guide of FIG. 2. FIG.
4 is a cross-sectional view taken along line AA in FIG.
FIG. 5 is a plan view for explaining the operation of a vertical guide.
6 is a cross-sectional view taken along the line BB in FIG.
FIG. 7 is a plan view showing another example of the vertical guide constituting the present invention.
8 is a cross-sectional view taken along the line DD of FIG.
[Explanation of symbols]
1 is a screw tightening machine main body, 5 is a body, 22 is a guide, 26 is a vertical surface, 27 is an inclined plane, 31 is a vertical guide, and 36 is a nose portion.

Claims (3)

Integrated with a driver bit to which rotation and axial movement are given by an air motor and an air piston, a screw supply unit that supplies a connected screw to the lower side of the driver bit, and a screw tightening machine main body that guides a screw driven out by the driver bit A nose part and a vertical guide attached to the lower end of the nose part and holding a screw,
The vertical guide is composed of at least two guides biased by a spring so as to abut at the lower end, and at least two planes facing the inner walls of the other guides are provided on the inner walls of the two guides. Screw tightening caused by recoil by inclining one plane along the moving direction of the screw so that the gap between the other guide inner wall plane is narrowed and the head of the screw being screwed in contact with the inclined plane A screw tightening machine characterized by preventing the machine body from rising . 2. The screw tightening machine according to claim 1 , wherein the inner wall shape of each guide is set so that the inner walls of both guides form a square weight when the lower ends of the both guides come into contact with each other without screws. . Integrated with a driver bit to which rotation and axial movement are given by an air motor and an air piston, a screw supply unit that supplies a connected screw to the lower side of the driver bit, and a screw tightening machine main body that guides a screw driven out by the driver bit And a vertical guide that is attached to a lower end of the nose portion and holds a screw. The vertical guide is composed of at least two guides biased by a spring so as to abut on the lower end. of the guide of the inner wall is provided with one planar facing the inner wall of the other guides, it causes the one plane along the traveling direction of the screw is inclined in such a gap narrows between the other guide inner wall plane, The screw head in the middle of screw tightening is brought into contact with the inclined plane to prevent the screw tightener body from rising due to reaction. Features and to Rene Ji tightening machine that was.

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