JP3073402U - Telescopic extension bar - Google Patents

Abstract

(57) [Summary] [Problem] It is possible to adjust the length to the optimum for each work place, to make a long size one, and there is no misalignment. SOLUTION: An electric screwdriver mounting shaft 2 is provided at one end, and a cylindrical sheath tube 1 is formed at the other end with a telescopic shaft stopper 4 fixed thereto. A grip 25 is attached to the outer peripheral surface 26 of the sheath tube 1.
Is slidably loosely fitted. A regular hexagonal telescopic shaft insertion hole 15 is formed inside the telescopic shaft stopper 4 so that the telescopic shaft insertion hole 15 is formed.
And a regular hexagonal column in the sheath tube 1
The telescopic shaft 16 having the recess 7 is inserted and loosely fitted in the longitudinal direction. A bit stopper 18 is fixed to the distal end of the telescopic shaft 16.
Further, a substantially cylindrical stopper 30 with a built-in magnet is freely rotatably fitted to the front half of the bit B attached to the bit stopper 18, and the inner peripheral surface 3 of the stopper 30 with a built-in magnet is provided.
An O-ring 35 is fitted in the inside 3, and a ring-shaped magnet 32 is buried in the diameter direction inside the distal end portion of the stopper 30 with a built-in magnet.

Description

[Detailed description of the invention]

[0001]

[Technical field to which the invention belongs]

 The present invention relates to an extension bar capable of adjusting the length between a bit and an electric screwdriver used for screw tightening work on a ceiling or a deep place.

[0002]

[Prior art]

 Conventionally, as an extension bar suitable for such a screwing work on a ceiling or a deep place, for example, as shown in FIG. 6, a mounting shaft T of an electric screwdriver is formed of a hexagonal prism having a length of about 30 cm and made of steel. And a stopper S for mounting a bit B is used.

[0003]

[Problems to be solved by the invention]

 The extension bar described in the prior art cannot be expanded or contracted because it is formed with a single mounting shaft, and the length is the most suitable for the height of the ceiling surface and the depth of the back, which vary depending on the conditions. However, there is a concern that if the length is too long, there is a risk that the core will run out.

[0004] In view of these problems, the present invention provides an extension bar that can be adjusted to an optimum length for each work place and that is easy to work without any misalignment even when formed in a long size. It has been devised for the purpose of

[0005]

[Means for Solving the Problems]

 An electric screwdriver mounting shaft is provided at one end, and a grip is slidably and loosely fitted on the outer peripheral surface of a cylindrical sheath tube having a telescopic shaft stopper fixed to the other end, and a regular hexagon inside the telescopic shaft stopper. The telescopic shaft insertion hole is formed, and a telescopic shaft having a regular hexagonal pillar and a positioning constriction recessed is inserted and inserted into the telescopic shaft insertion hole and the sheath tube in parallel with the longitudinal direction of the sheath tube. Secure the bit stopper to the part.

[0006]

[Embodiment of the invention]

 The present invention will be described with reference to the drawings. In FIGS. 1 to 4, the sheath tube 1 is formed of, for example, a cylindrical steel tube having a length of about 30 cm, and one end thereof is a commercially available bit that can be attached to a stopper of an electric screwdriver. The electric driver mounting shaft 2 formed in a substantially hexagonal column shape having substantially the same shape as the shaft of the shaft is inserted and fixed by driving, for example, a knock pin 3 in the diametrical direction, and the other end portion has an inner end of a telescopic shaft stopper 4. The part is inserted and fixed. More specifically, the cylindrical main body 5 of the expansion / contraction shaft stopper 4 is formed in a substantially cylindrical shape using, for example, a steel material, and the positioning ball loose fitting holes 6, 6 are formed in the thick portion of the cylindrical main body 5 in the diameter direction. The positioning balls 7 are loosely fitted in the respective positioning ball loose fitting holes 6 by drilling them at the opposing positions. The slide cover 8 covers the outer peripheral surface 9 of the cylindrical main body 5 in a ring shape with a wide width, and is loosely fitted along the outer peripheral surface 9 so as to slide in the longitudinal direction. On the inner peripheral surface 10 of the slide cover 8, there is provided a ball escape cavity 11 and a ring spring 12 having a substantially arcuate vertical cross section and abutting on a part of the positioning ball 7 along the circumference of the inner peripheral surface 10. A positioning groove 13 to be wound is formed, and a ball restraining surface 14 is formed by an inner peripheral surface 10 at an intermediate portion between the ball escape cavity 11 and the positioning groove 13.

The telescopic shaft insertion hole 15 is formed in the center of the longitudinal section of the cylindrical main body 5 in a regular hexagon parallel to the longitudinal direction. The telescopic shaft insertion hole 15 is made of, for example, a steel material and has a length of about 30 cm. A telescopic shaft 16 formed into a square hexagonal prism is inserted. The positioning constrictions 17, 17 are recessed along the outer peripheral surface of the expansion / contraction shaft 16 in a U-shaped longitudinal section from the outer peripheral surface. More specifically, the positioning constriction 17 is formed to have a size to which a part of the surface of the positioning ball 7 is fitted. .

The bit stopper 18 is fixed to the outer end of the telescopic shaft 16 inserted into the telescopic shaft insertion hole 15 by driving, for example, a knock pin. More specifically, the bit stopper 18 is provided with a bit insertion hole 20 having a hexagonal vertical section for inserting a commercially available bit into a cylindrical main body 19 and a positioning ball 21 fitted into a constricted portion of the bit. A ball restraining surface 22 for holding the ball 21 from the outside and a ring-shaped slide cover 24 that covers the ball escape cavity 23 in the longitudinal direction on the outer circumferential surface of the main body 19 provided on the inner circumferential surface are formed. The grip 25 is formed in a substantially cylindrical shape having a slightly larger diameter at the center in the longitudinal direction, and the inner peripheral surface 27 is loosely fitted to the outer peripheral surface 26 of the sheath tube 1.

Next, when the present invention is implemented and used, for example, when the telescopic shaft 16 is extended long in the work on the ceiling or in a deep place, the slide cover 8 of the telescopic shaft stopper 4 is moved to move the ball. When the escape cavity 11 is moved to a position outside the positioning ball 7, the positioning ball 7 fitted in the positioning constriction 17 escapes into the ball escape cavity 11. The slide cover 8 is slid at a position where the positioning ball 7 fits into the positioning constriction 17 at a desired length position, and the positioning ball 7 is suppressed from the outside by the ball restraining surface 14. The positioning ball 7 fits into the positioning constriction 17 and can be fixed to a desired length. When the length L between the telescopic shaft stopper 4 and the bit stopper 18 is increased by extending the telescopic shaft 16 long, the grip 25 is moved near the telescopic shaft stopper 4 and the clip 25 is grasped by hand. Performing work such as screw tightening while supporting it can prevent the centering. Then, a stopper of a commercially available electric screwdriver (not shown) is inserted and attached to the electric screwdriver mounting shaft 2 side, and a commercially available screw tightening bit (not shown) is attached to the bit stopper 18, thereby increasing the height. Work in deep and deep places can be performed under the best length conditions, and the screw attached to the tip of the bit can be prevented from falling by magnetic force, and there is no fear of damaging the wall surface.

[0010]

【Example】

 By providing a packing 28 at the inner end of the telescopic shaft 16 in close contact with the inner surface of the sheath tube 1, the core of the telescopic shaft 16 can be prevented. Further, if a sliding packing 29 is provided on the inner surface of the grip 25 so as to be in close contact with the outer peripheral surface of the sheath tube 1, misalignment can be suppressed.

Further, as shown in FIG. 5, a substantially cylindrical stopper 30 with a built-in magnet which can be loosely fitted to the first half of the bit B attached to the bit stopper 18 is formed. A ring-shaped magnet 32 formed in a ring shape from, for example, neodymium material is held inside by a ring-shaped washer and buried in the diameter direction. More specifically, it is preferable that the entire length Z of the stopper 30 with a built-in magnet is formed so that the tip of the bit B projects about 4 m 2 / m. The outer diameter of the ring-shaped magnet 32 formed in a ring shape is slightly larger than the inner diameter of the inner peripheral surface 33 of the stopper 30 with a built-in magnet, and is buried in the thick portion 34, and the inner diameter is larger than the outer diameter of the bit B. The bit B is rotatably fitted inside the ring-shaped magnet 32 so as to be freely rotatable. The O-ring 35 made of a rubber material is formed to have a slightly larger diameter than the inner diameter of the inner peripheral surface 33 and is diametrically fitted into the thick portion 34. The inner diameter is formed to be slightly larger than the outer diameter of the bit B. It is loosely fitted on the outer peripheral surface of bit B. This prevents the screw N attached to the tip of the bit B from spilling out due to the attractive force of the ring-shaped magnet 32, and is suitable for upward work at a high position. When the screw is tightened, the distal end surface 31 abuts against the wall surface, and the screw N is tightened more deeply than necessary, and the wall surface is not damaged.

[0012]

[Effect of the invention]

 As described above, according to the present invention, the telescopic shaft can be adjusted to a desired optimum length from the sheath tube, and a long size can be made in a state in which the telescopic shaft is added to the sheath tube. Even so, the center part can be supported by the grip, so there is no centering, and the screw attached to the tip of the bit can be prevented from falling by magnetic force, and there is no fear of damaging the wall.

[Brief description of the drawings]

FIG. 1 is a front view showing a cross section of a telescopic extension bar cut off along a center line of symmetry.

FIG. 2 is a longitudinal sectional view showing a main part of a telescopic extension bar.

FIG. 3 is a longitudinal sectional view taken along line AA of FIG. 2;

FIG. 4 is a front view of a telescopic extension bar.

FIG. 5 is a diagram showing an example of another embodiment.

FIG. 6 is a front view showing a conventional extension bar.

[Explanation of symbols]

 Reference Signs List 1 sheath tube 2 electric screwdriver mounting shaft 4 telescopic shaft stopper 5 cylindrical main body 7 positioning ball 8 slide cover 11 ball escape cavity 12 ring spring 14 ball restraining surface 15 telescopic shaft insertion hole 16 telescopic shaft 17 positioning constriction 18 bit stopper 19 main body 20 Bit insertion hole 21 Positioning ball 22 Ball suppression surface 23 Ball escape cavity 24 Slide cover 25 Grip 30 Stopper with built-in magnet 32 Ring magnet 35 O-ring

Claims (3)

[Utility model registration claims] 1. An electric screwdriver mounting shaft 2 is provided at one end, and a grip 25 is slidably and loosely fitted on an outer peripheral surface 26 of a cylindrical sheath tube 1 to which an elastic shaft stopper 4 is fixed at the other end. A telescopic shaft insertion hole 15 having a regular hexagon shape inside the telescopic shaft stopper 4 and a telescopic shaft 16 having a regular hexagonal column shape inside the sheath tube 1 and having a positioning constriction 17 recessed are inserted in parallel with the longitudinal direction of the sheath tube 1. A telescopic extension bar which is loosely fitted and has a bit stopper 18 fixed to the end of a telescopic shaft 16. 2. The telescopic shaft stopper 4 has a regular hexagonal telescopic shaft insertion hole 15 formed inside and a ring-shaped slide on the outer peripheral surface 9 of a cylindrical main body 5 in which a positioning ball 7 is inserted into a thick portion. The cover 8 is loosely fitted, and the inner peripheral surface 1 of the slide cover 8 is
The ball escape cavity 11 and the ball restraining surface 14 formed on the positioning ball 7 are used to fix the positioning ball 7 to the positioning shaft 17 of the telescopic shaft 16.
The telescopic extension bar according to claim 1, wherein the extension bar is prevented from being fitted into the extension bar. 3. A substantially cylindrical stopper 30 with a built-in magnet is freely rotatably fitted to the front half of the bit B attached to the bit stopper 18, and the stopper 3 with a built-in magnet.
2. A telescopic extension according to claim 1, wherein a ring-shaped magnet is buried diametrically inside the front end face of the O. 0, and an O-ring is diametrically fitted into an inner peripheral surface of the stopper with built-in magnet. bar.