KR101872495B1

KR101872495B1 - Screw driver

Info

Publication number: KR101872495B1
Application number: KR1020160173656A
Authority: KR
Inventors: 김영롱
Original assignee: 김영롱
Priority date: 2016-12-19
Filing date: 2016-12-19
Publication date: 2018-06-28
Also published as: KR20180070995A

Abstract

The present invention relates to a screwdriver, and more particularly, to a screwdriver having a handle portion having an insertion groove formed at one side thereof and a coupling portion formed at a tip side thereof; A shaft accommodated in the insertion groove of the handle and being adjustable in length; A fixed cap disposed to surround the engaging portion of the handle portion and movable in the longitudinal direction by a predetermined distance; And an elastic member disposed between the fixed cap and the handle to provide an elastic force to the fixed cap, wherein the fixed cap is movable longitudinally by a predetermined distance by compression or elastic recovery of the elastic member, , The length of the shaft is extended with respect to the handle, but the length is not reduced, or the length is increased or decreased, or the length is increased or decreased, as the fixed cap is moved.

Description

Screw driver [0002]

The present invention relates to a screwdriver, and more particularly, to a screwdriver capable of extending a shaft in a state in which a separate external force is not applied, but not reducing the length of the shaft, thereby improving user convenience.

Generally, a screwdriver is a tool used for tightening or loosening a screw. The screwdriver has a shaft with a tip (-) or a cross (+) shaped tip at its end, and a shaft And a handle for rotating the shaft according to the setting.

The shaft has a generally rectangular or hexagonal cross section, and the screw is screwed or loosened using a screwdriver equipped with a shaft having a tip formed at the end thereof in accordance with the groove shape of the screw to be tightened or loosened.

In recent years, there has been provided a screw provided with a shaft on which both ends of a cross shape and a straight shape are machined, a shaft is separated with respect to the handle, the direction is reversed and fixed to the handle, .

Particularly, when screw drivers are interfered with other parts or are restricted by space when fastening or releasing screws, the screw driver can be adjusted in length to provide a convenient screw driver.

However, in the conventional screw driver as described above, since the shaft can be separated from the handle and the length can be adjusted, the shaft can not be perfectly fixed with respect to the handle, There is a problem that when the screw is tightened or loosened and the pressing force is applied to the knob portion, the shaft is pushed inward with respect to the knob portion.

In other words, when the screw is tightened with the tip formed on the end of the shaft to tighten or loosen the screw, the shaft is pushed toward the inside of the handle by the pressing force when the knob is rotated while applying a pressing force to the knob in the shaft direction. There is a case in which the length of the shaft is reduced, which results in poor functionality.

Korean Utility Model Registration No. 20-0277283 (May 22, 2002) Korean Patent Publication No. 2002-0064816 (Aug. 10, 2002)

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a method and an apparatus for adjusting a length of a shaft with respect to a handle, A screw driver capable of extending the length of the shaft but not reducing the length of the shaft is provided to enhance user convenience.

That is, a technical problem to be solved by the present invention is to provide a method for adjusting a length of a shaft in a shaft direction with respect to a handle by adjusting a length of the shaft to a set length, The screw is prevented from being pushed into the handle portion despite the pressing force when the screw driver is rotated while applying a pressing force, thereby improving the reliability of the function.

It is another object of the present invention to provide an apparatus and a method for adjusting the length of a shaft in a state where a separate external force is not applied, So as to provide a screw driver that improves user convenience.

The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

According to an aspect of the present invention, there is provided a screw driver comprising: a handle portion having an insertion groove formed in one side direction and a coupling portion formed on a tip side; A shaft accommodated in the insertion groove of the handle and being adjustable in length; A fixed cap disposed to surround the engaging portion of the handle portion and movable in the longitudinal direction by a predetermined distance; And an elastic member disposed between the fixed cap and the handle to provide an elastic force to the fixed cap, wherein the fixed cap is movable longitudinally by a predetermined distance by compression or elastic recovery of the elastic member, , The length of the shaft is extended with respect to the handle as the fixed cap moves, but the length can not be reduced or the length can be increased or decreased, or the length can be adjusted so as not to be elongated or reduced have.

At least one ball receiving hole is formed in the circumferential surface of the coupling portion. The ball receiving hole communicates with the insertion groove of the handle portion. The ball receiving hole is inserted into the ball receiving hole, As shown in FIG.

The fixing cap may be formed with an insertion hole for inserting the engaging portion, a first engaging protrusion and a second engaging protrusion protruding inward at a predetermined interval are formed on an inner circumferential surface of the insertion hole, The first engaging protrusion and the second engaging protrusion may be formed as a tapered surface that is inclined so that the diameter gradually decreases in the direction of the handle.

The elastic member may be disposed between the second latching portion and a step portion formed to be stepped on an outer periphery of the handle portion.

Therefore, when the ball is brought into close contact with the tapered surface, the ball is in a state of being pressed against the outer surface of the shaft by the elastic restoring force of the elastic member, and the shaft is pulled out from the insertion groove of the handle, The ball may extend from the tapered surface of the fixed cap to a portion where the diameter of the tapered surface increases to thereby extend the shaft. When the shaft is inserted into the insertion groove of the handle to reduce the length of the shaft, The shaft may not be reduced in length due to the rolling action of the tapered surface of the fixed cap to a portion where the diameter is reduced.

In addition, when the fixed cap is moved in the direction of the handle while compressing the elastic member, the ball is positioned at a portion having a large diameter on the tapered surface of the fixed cap and the pressing force on the tapered surface is released, The shaft can be received with respect to the insertion groove of the handle, so that the length of the shaft can not be increased or decreased.

In addition, the shaft may have a fixing groove recessed inwardly at predetermined intervals, and when the ball is positioned in the fixing groove of the shaft, the fixing cap is moved by the elastic restoring force of the elastic member , The second engaging protrusion of the fixed cap can press the ball into the fixing groove of the shaft.

On the other hand, a fitting groove is formed on the front end circumferential surface of the engaging portion, and a stopper ring is fitted into the fitting groove. The position of the fixed cap can be restricted by the stopper ring.

Other specific details of the invention are included in the detailed description and drawings.

According to the screw driver according to the embodiment of the present invention, the length of the shaft can be freely adjusted with respect to the handle, and in the state where no external force is applied, the shaft can be extended only, The effect of increasing user convenience can be provided.

That is, when the tip of the shaft is tightly attached to the screw to tighten or loosen the screw in a state in which the length of the shaft is adjusted to the set length, and then the screw is rotated while applying a pressing force to the knob in the shaft direction, The shaft is not pushed into the inside of the handle, but the reliability of the function is improved.

In addition, according to the screw driver according to the embodiment of the present invention, the length of the shaft can be freely extended when no external force is applied. In the case of reducing the length of the shaft, It is possible to provide an effect that the user convenience is further improved.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

1 is an overall perspective view of a screwdriver according to an embodiment of the present invention;
Fig. 2 is an exploded perspective view of Fig. 1; Fig.
FIG. 3 is a perspective view showing a state in which the length of the shaft can be elongated but the shaft is not reduced in length in the screw driver according to the embodiment of the present invention,
Fig. 4 is a cross-sectional view of Fig. 3,
5 is an enlarged cross-sectional view of the main part of Fig.
6 is a sectional view taken along the line AA in Fig. 5;
7 is a perspective view showing a state in which a length of a shaft can be extended and a length of a shaft can be reduced by a pulling action of a fixed cap in a screwdriver according to an embodiment of the present invention.
8 is a cross-sectional structural view of Fig.
FIG. 9 is an enlarged cross-sectional view of the main part of FIG. 8;
10 is a sectional view taken along line BB of Fig.
11 is a perspective view of a screw driver according to an embodiment of the present invention, in which both the length of the shaft and the length of the shaft are not reduced as the shaft is set to a predetermined length.
Fig. 12 is a sectional structural view of Fig. 11; Fig.
13 is an enlarged cross-sectional view of the main part of Fig. 12;
14 is a sectional view taken along line CC of Fig.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Further, the embodiments described herein will be described with reference to cross-sectional views and / or schematic drawings that are ideal illustrations of the present invention. Thus, the shape of the illustrations may be modified by manufacturing techniques and / or tolerances. In addition, in the drawings of the present invention, each component may be somewhat enlarged or reduced in view of convenience of explanation. Like reference numerals refer to like elements throughout the specification.

Hereinafter, a preferred embodiment of a screw driver according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is an overall perspective view of a screwdriver according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of FIG.

3 is a perspective view showing a state in which the length of the shaft can be elongated but the shaft is not reduced in length in the screwdriver according to the embodiment of the present invention, Fig. 5 is an enlarged sectional view of Fig. 4, and Fig. 6 is a sectional view taken along the line AA of Fig.

7 is a perspective view showing a state in which the length of the shaft can be extended and the length of the shaft can be reduced by the pulling action of the fixed cap in the screwdriver according to the embodiment of the present invention, Fig. 9 is an enlarged sectional view of the main part of Fig. 8, and Fig. 10 is a sectional view taken along line BB of Fig.

11 is a perspective view of a screw driver according to an embodiment of the present invention in which the length of the shaft is not extended and the length of the shaft is not reduced as the shaft is set to a predetermined length, Fig. 13 is an enlarged cross-sectional view of Fig. 12, and Fig. 14 is a cross-sectional view taken along the line CC of Fig.

1 and 2, a screw driver 100 according to an embodiment of the present invention includes a shaft 110, a handle 200, a fixed cap 300, and an elastic member 250 And the like.

The shaft 110 may have a cross-shaped tip 112 or 114 formed at the end thereof and a predetermined length in the form of a polygonal cross-section.

The screw driver 100 according to the embodiment of the present invention will be described as an example in which a shaft 110 having crosses and straight tips 112 and 114 at both ends thereof is formed as an example, , And a shaft 110 having straight or cross-shaped tips 112 and 114 formed at only one end thereof may be provided.

In the shaft 110, the fixing groove 116 may be formed on the inner side of the cross-shaped tip 112 and the inside of the flat tip 114, respectively, inwardly with respect to the circumferential surface, The function of the controller 116 will be described later in detail.

For reference, the shaft 110 applied to the screw driver 100 according to the embodiment of the present invention may be formed with a fixing groove 116 formed at an inner circumference at a predetermined interval in the entire length.

The grip portion 200 includes a grip portion 210 having an insertion groove (not shown) inserted therein by a predetermined depth in one direction to insert the shaft 110, And a coupling part 220 formed on the distal end side of the grip part 210.

A stopper ring 240 for preventing the detachment of the fixed cap 300 is inserted in the outer circumference of the tip side of the coupling part 220 At least one ball receiving hole 226 may be formed at a position spaced apart from the fitting groove 222 by a predetermined distance.

The ball receiving hole 226 communicates with the insertion groove of the handle 200, and the ball 230 can be inserted into the ball receiving hole 226.

For reference, in the screw driver 100 according to the embodiment of the present invention, three ball receiving holes 226 and balls 230 are described as an example, but this is only one embodiment, But the present invention is not limited thereto, and the number thereof may be added or subtracted.

That is, when the shaft 110 has a hexagonal shape, it is preferable that the ball receiving hole 226 and the ball 230 are positioned every 120 degrees so that the shaft 110 can be stably gripped in the circumferential direction In some cases, the ball receiving holes 226 and the balls 230 may be provided in a number corresponding to the cross-sectional shape of the shaft 110.

Of course, when the shaft 110 has a rectangular shape, four ball receiving holes 226 and balls 230 may be provided.

Accordingly, the ball 230 is brought into contact with the outer surface of the shaft 110 inserted into the insertion groove of the handle 200, so that the shaft 110 is extended or reduced in length, And the function of preventing the reduction of the length is performed. The operation relation therebetween will be described later in detail.

In addition, when the ball 230 is inserted into the fixing groove 116 of the shaft 110, the shaft 110 can also function to maintain the fixed state without length extension and length reduction, The operating relationship therebetween will be described in detail later.

Meanwhile, the coupling portion 220 of the handle 200 may be formed in a cylindrical shape having an insertion hole for insertion.

The inner circumferential surface of the inner surface of the insertion hole of the fixed cap 300 has a first engagement protrusion 310 protruding inward and an inner circumferential surface at a position spaced apart from the first engagement protrusion 310 And a second latching protrusion 320 protruding inwardly may be respectively formed.

At this time, the inner circumferential surface between the first engaging protrusion 310 and the second engaging protrusion 320 may be formed of a tapered surface 330 having an inclination such that the inner diameter gradually decreases or increases.

That is, the tapered surface 330 of the fixed cap 300 may have a rhomboid shape such that the inner diameter decreases from the front end to the rear end.

The tapered surface 330 of the fixed cap 300 is in contact with one surface of the ball 230 inserted into the ball receiving hole 226 of the coupling part 220, And the function of releasing the contact with the one surface or releasing the contact with the other surface is performed. The operation relation therebetween will be described in detail later.

The elastic member 250 is disposed in a state of being engaged with the engaging portion 220 and is positioned between the step portion 224 of the grip portion 200 and the second engaging protrusion 320 of the fixed cap 300 .

The fixed cap 300 can be moved to the rear side of the engaging portion 220 by compressing the elastic member 250 and the elastic force of the elastic member 250 can be transferred to the front side of the engaging portion 220 To move to the position.

In this case, when the stopper ring 240 is engaged with the fitting groove 222 of the coupling part 220, the fixing cap 300 can be prevented from being displaced forward by the stopper ring 240.

The operation of the screw driver 100 having the above structure will be described in detail with reference to FIGS. 3 to 14. FIG.

3 is a perspective view showing a state in which the length of the shaft 110 can be elongated but the length of the shaft 110 is not reduced in the screwdriver 100 according to the embodiment of the present invention, Fig. 5 is an enlarged sectional view of Fig. 4, and Fig. 6 is a sectional view taken along the line AA of Fig.

3 to 6, in a state where the fixing cap 300 is positioned outside the engaging portion 220 of the handle 200, no external force is applied to the inserting groove of the handle 200, The length of the shaft 110 can be reduced by inserting the shaft 110 with respect to the insertion groove of the handle 200. On the contrary, the shaft 110 is not inserted into the insertion groove of the handle 200,

5 and 6, in a state where the fixing cap 300 is positioned outside the engaging portion 220 of the handle 200, when no external force is applied, due to the elastic force of the elastic member 250 The fixed cap 300 is given a force to move toward the distal end of the coupling portion 220. [

The ball 230 inserted into the ball receiving hole 226 of the coupling part 220 is pressed by the tapered surface 330 of the fixed cap 300 according to the movement of the tip of the fixed cap 300, So that the surface of the shaft 110 is pressed against the outer surface of the shaft 110.

In this state, when the user pulls the shaft 110 against the insertion groove of the handle 200, the ball 230 moves from the tapered surface 330 of the fixed cap 300 to the tip of the inner diameter, So that the shaft 110 can be pulled out of the insertion groove of the handle 200. This allows the shaft 110 to be pulled out of the insertion groove of the handle 200. As a result, Length extension is enabled.

That is, when the shaft 110 is pulled only by a force larger than the elastic force of the elastic member 250, the ball 230 moves from the tapered surface 330 of the fixed cap 300 to the tip side where the inner diameter gradually increases in diameter, The ball 230 can come out of the insertion groove of the handle 200 as the pressing force of the ball 230 on the one side of the shaft 110 becomes somewhat loose.

Conversely, when the shaft 110 is to be pushed into the insertion groove of the handle 200, the shaft 110 can not be pushed into the insertion groove by the pressing force of the ball 230.

That is, in a state where the length of the shaft 110 is set, when the user aligns the tips 112 and 114 formed at the ends of the shaft 110 with the grooves of the screws, the user rotates the knob 200 while applying a pressing force in the direction of the shaft 110 The balls 230 roll on the tapered surface 330 of the fixed cap 300 toward the rear end where the diameter of the inner diameter is gradually reduced. At this time, the balls 230 are moved to the outer surface of the shaft 110 The ball 230 rotates toward the rear end side of the tapered surface 330 having a diameter smaller than the diameter connecting the outer ends of the balls 230 in the compressed state, So that the shaft 110 can not be pushed into the insertion groove of the handle 200.

As described above, in the screwdriver 100 according to the embodiment of the present invention, when no external force is applied in a state where the fixed cap 300 is positioned outside the engaging portion 220 of the handle 200, Can be pulled out by a desired position and pulled out of the insertion groove of the handle 200 by the pulling force of the handle 200. On the contrary, it can not be pushed into the insertion groove of the handle 200 of the shaft 110.

Therefore, the screw driver 100 according to the embodiment of the present invention sets the length of the shaft 110 to a length desired by the user, and then sets the tips 112 and 114 formed at the ends of the shaft 110 The shaft 110 is prevented from being pushed into the insertion groove of the handle 200 so that the screw can be tightened or loosened smoothly even if the handle 200 is pressed and rotated in the direction of the shaft 110. [ The reliability of the bar and the function can be greatly improved.

In addition, as the balls 230 are further pressed against the outer surface of the shaft 110, the shaft 110 is more stably fixed to the grip 200, .

7 and 8, when the length of the shaft 110 is to be reduced in a state in which the length of the shaft 110 is not reduced but the length of the shaft 110 is not reduced as described above, The operation of the fixed cap 300 may be shifted slightly to the rear end side while compressing the elastic member 250 as shown in FIG.

7 is a perspective view of a screw driver 100 according to an embodiment of the present invention in which a length of the shaft 110 is reduced and a length of the shaft 110 is reduced by the pulling action of the fixed cap 300. [ Fig. 8 is a sectional view of Fig. 7, Fig. 9 is an enlarged sectional view of Fig. 8, and Fig. 10 is a sectional view of the BB line of Fig.

7 to 10, when the user slightly pulls the fixed cap 300 in the direction of the pull tab 200 to move the fixed cap 300, the fixed cap 300 compresses the elastic member 250, (200).

The elastic member 250 is disposed between the second latching protrusion 320 of the fixed cap 300 and the stepped portion 224 that is stepped on the outer periphery of the knob portion 200, Is pulled in the direction of the knob part 200, the positional movement is performed while compressing the elastic member 250.

9 and 10, when the fixed cap 300 is moved toward the handle 200, the ball 230 moves in the direction of the inner periphery of the tapered surface 330 of the fixed cap 300, The pressing force of the ball 230 against the outer surface of the shaft 110 is released.

That is, since the ball 230 is positioned at a portion having a large inner diameter on the tapered surface 330 of the fixed cap 300, the pressing force of the ball 230 by the tapered surface 330 of the fixed cap 300 The one side of the ball 230 is also released from the outer surface of the shaft 110 so that the shaft 110 can be pulled out or inserted into the insertion groove of the handle 200.

Therefore, by pushing the shaft 110 into the insertion groove of the handle 200 in this state, the length of the shaft 110 can be reduced.

In this state, when the pulling action against the fixed cap 300 pulled toward the pull tab 200 is released, the fixed cap 300 is again pulled back by the resilient restoring force of the elastic member 250 3 to 5 so that the ball 230 is again pressed against the outer surface of the shaft 110, so that the fixed cap 300 is moved to the position shown in FIGS. The length of the shaft 110 can be extended but the length can not be reduced.

In the case of the screw driver 100 according to the embodiment of the present invention, since the fixing grooves 116 can be formed on the outer surface of the shaft 110 at regular intervals, the shaft 110 The shaft 110 may be set such that both the length extension and the length reduction are not performed in the state where the external force is not applied. 11 to Fig. 14.

11 is a view showing a state in which both the extension of the shaft 110 and the reduction of the length of the shaft 110 are not performed as the set length of the shaft 110 is set in the screwdriver 100 according to the embodiment of the present invention Fig. 12 is a sectional view of Fig. 11, Fig. 13 is an enlarged sectional view of Fig. 12, and Fig. 14 is a sectional view of a CC line of Fig.

As shown in FIGS. 3 to 6, in a state in which the length of the shaft 110 is elongated but the length of the shaft 110 is not reduced, when the user pulls the shaft 110, When the ball 230 is inserted into the fixing groove 116 of the shaft 110 and the ball 230 is inserted into the fixing groove 116 of the shaft 110, Is reduced.

Accordingly, the fixed cap 300 is not restricted by the movement of the ball 230 in the direction of the shaft 110 because the ball 230 is not in close contact with the tapered surface 330. The fixed cap 300 includes the elastic member 250 So as to move in the direction of the shaft 110.

When the end of the second latching protrusion 320 of the fixed cap 300 reaches the position of the ball 230 by the movement of the fixed cap 300 in the direction of the shaft 110, The ball 230 is held in the fixing groove 116 of the shaft 110 by pressing the ball 230 against the fixing groove 116 of the shaft 110, The ball 230 can not be inserted into the insertion groove of the handle 200 and can not be inserted, so that the ball 230 can be held in a fixed state.

Therefore, the user holds the shaft 110 fixed in a predetermined length, and in this state, it is possible to perform an operation of tightening or loosening the screw.

In this state, in order to adjust the length of the shaft 110, that is, to extend or reduce the length of the shaft 110, as described above with reference to FIGS. 7 to 10, The shaft 300 is pulled toward the handle 200 so that the ball 230 is positioned at a portion having a large diameter on the tapered surface 330 of the fixed cap 300, The length can be easily adjusted by pulling or pushing in the insertion groove.

As described above, according to the screw driver 100 according to the embodiment of the present invention, the user can select and adjust the length of the shaft 110 as required, The length of the shaft 110 can be increased as the shaft 110 is pulled out of the grip 200. Conversely, since the shaft 110 is not pushed into the grip 200, the length of the shaft 110 is not reduced. It is prevented that the shaft 110 is pushed into the insertion groove of the handle 200 when the grip 200 is pressed and rotated so that the reliability of the function is greatly improved and the user's satisfaction is enhanced Can be provided.

In addition, the screw driver 100 according to the embodiment of the present invention can be fixed so that the length of the shaft 110 is not elongated or reduced in a state where the screw driver 100 is set to a predetermined length, if necessary, .

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: screw driver 110: shaft
112, 114: Tip 116: Fixing groove
200: handle part 210: grip part
220: engaging portion 222: engaging groove
224: step portion 226: ball insertion hole
230: Ball 240: Stopper ring
250: elastic member 300: fixed cap
310: first stopping projection 320: second stopping projection
330: Taper face

Claims

A handle portion having an insertion groove formed in one direction and having a coupling portion on a tip side;
A shaft which is accommodated in the insertion groove of the handle and is adjustable in length, the fixing groove being formed at an inner circumference at a predetermined interval;
And an insertion hole for inserting the engaging portion is formed on the inner circumferential surface of the insertion hole, the engaging portion is formed on the inner circumferential surface of the insertion hole, A first locking protrusion and a second locking protrusion are formed between the first locking protrusion and the second locking protrusion, and a tapered surface of the fixed cap is formed between the first locking protrusion and the second locking protrusion so that the diameter gradually decreases in the direction of the knob. And
And an elastic member disposed between the fixed cap and the handle to provide an elastic force to the fixed cap,
Wherein at least one ball receiving hole is formed on the circumferential surface of the coupling portion, the ball receiving hole communicates with the insertion groove of the handle,
And a ball inserted into the ball receiving hole and being in contact with or released from the outer surface of the shaft inserted into the insertion groove,
The fixed cap is movable longitudinally by a predetermined distance by compression or elastic restoration of the elastic member,
According to the movement of the fixed cap,
When the ball is in close contact with the tapered surface, the ball is in a compressed state with the outer surface of the shaft due to the elastic restoring force of the elastic member. When the shaft is pulled out from the insertion groove of the handle to extend the length, The ball is allowed to extend from the tapered surface of the fixed cap to a portion where the diameter of the tapered surface increases to thereby extend the shaft. When the shaft is inserted into the insertion groove of the handle to reduce the length, The shaft is not reduced in length due to the rolling action of the tapered surface of the cap to a portion where the diameter is reduced,
When the fixed cap is moved in the direction of the handle while compressing the elastic member, the ball is positioned at a portion having a large diameter on the tapered surface of the fixed cap and the pressing force against the tapered surface is released, It is possible to store the shaft with respect to the insertion groove, thereby extending and reducing the length of the shaft,
When the ball is located in the fixing groove of the shaft, the fixing cap is moved by the elastic restoring force of the elastic member, and the second latching part of the fixing cap presses the ball into the fixing groove of the shaft Features a screwdriver.

delete

The method according to claim 1,
The elastic member
Wherein the first screw portion is disposed between the second latching portion and the step portion formed stepwise on the outer periphery of the handle portion.

delete

The method according to claim 1,
Wherein a fitting groove is formed on a peripheral surface on the tip side of the engaging portion,
A stopper ring is fitted in the fitting groove,
Wherein the fixed cap is limited in positional movement by the stopper ring.