JPH10339310A - Extensible/contractible member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an extensible/contractible member wherein length can be easily adjusted. SOLUTION: When a storage recessed part 9 of an annular member 4 is provided in a position corresponding to a through window of a cylinder member 3, a lock member 5, by energizing force of a compression coil spring 6, is protruded in a diametric direction inward of the annular member 4, a tip end part is penetrated in the through window 8, in this way, the tip end part of the lock member 5 is inserted in a peripheral groove 7 of a columnar member 2, its movement in an axial direction is regulated. From a regulated condition, when the annular member 4 is rotated in a direction of arrow mark, a slope 10 of the lock member 5 presses a slope 8a of the through window, by reaction force from the slope 8a, the lock member 5 is moved in diametric direction outward of the annular member 4 against energizing force of the compression coil spring 6, in the last end, a tip end part of the lock member 5 climbs over the slope 8a of the through window, and runs on a peripheral part of the cylinder member 3, in this way, movement in the axial direction of the columnar member 2 is permitted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a telescopic member which is used for legs such as a tripod, a stepladder, a desk, a table, and a chair and whose length can be freely adjusted.

[0002]

2. Description of the Related Art A conventional telescopic member of this type includes:
For example, the shaft member is axially movably inserted into the cylindrical member, and the shaft member is moved in the axial direction by pressing the outer peripheral portion of the shaft member with the tip of a screw member screwed in from the outer peripheral portion of the cylindrical member. There is a known configuration in which the screw member is loosened from the restricted state to release the pressing on the outer peripheral portion of the shaft member, thereby allowing the shaft member to move in the axial direction.

[0003]

However, in such a conventional telescopic member, the screw member must be rotated a plurality of times when adjusting the length by allowing and restricting the axial movement of the shaft member. Therefore, there is an inconvenience that it takes time to adjust the length.

The present invention has been made in order to solve such a disadvantage, and an object of the present invention is to provide a telescopic member capable of easily adjusting the length.

[0005]

In order to achieve the above object, a telescopic member according to the present invention is characterized in that a circumferential groove formed in an outer peripheral portion along a circumferential direction has a predetermined interval in an axial direction. A plurality of provided rod members, the rod members are inserted so as to be relatively movable in the axial direction, a cylindrical member having a through window in a peripheral wall portion, and a rotatable outer member rotatably moved to a position corresponding to the through window of the cylindrical member. An annular member that is inserted and has a storage recess in the inner peripheral portion, and is housed in the storage recess so as to be movable in a radial direction of the annular member and a distal end portion is protrudable from the inner peripheral portion of the annular member. A locking member having an inclined portion formed on a side of the annular member facing the circumferential direction of the distal end portion and gradually narrowing toward a radially inward direction of the annular member; and A biasing member for biasing inward in the radial direction, wherein the locking member is When at the position corresponding to the through window, the urging force of the urging member protrudes radially inward of the annular member so that the tip portion penetrates the through window, whereby the circumferential groove of the rod member is formed. The distal end is inserted into the rod member to restrict the axial movement of the rod member, and when the annular member is rotated from the restricted state, the inclined portion presses the side edge of the through-hole facing in the circumferential direction. The cylindrical member moves radially outward of the annular member against the urging force of the urging member due to the reaction force from the side edge, and finally the leading end portion gets over the side edge of the through window. Characterized in that the rod member is allowed to move relative to the outer periphery of the rod member in the axial direction.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a front view of a telescopic member according to an embodiment of the present invention, and FIG.
3 is a sectional view taken along the line III-III in FIG. 2, and FIG. 4 is an explanatory view for explaining the movement of the locking member when the annular member is rotated.

[0007] As shown in FIGS.
Are cylindrical members (bar members) 2, cylindrical members (cylindrical members) 3, annular members 4, locking members 5, and compression coil springs (biasing members).
6 is provided.

A circumferential groove 7 is formed in the outer peripheral portion of the columnar member 2 and extends all around the circumferential direction. The circumferential grooves 7 are provided at a plurality of positions (here, three positions) at substantially equal intervals in the axial direction. I have. The inner diameter of the cylindrical member 3 is slightly larger than the outer diameter of the cylindrical member 2, and the cylindrical member 2 is inserted so as to be relatively movable in the axial direction. A plurality of square through-holes 8 are provided in the peripheral wall of the cylindrical member 3 at substantially equal intervals in the circumferential direction, and the size of one side of the through-window 8 is substantially the same as the width of the peripheral groove 7. I have. Further, both side edges of the through window 8 facing in the circumferential direction are inclined surfaces 8a that gradually become narrower inward in the radial direction of the cylindrical member 3 (see FIG. 3).

The annular member 4 is formed in a short cylindrical shape whose inner diameter is slightly larger than the outer diameter of the cylindrical member 3, and is rotatably inserted at a position corresponding to the through window 8 of the cylindrical member 3. On the inner peripheral surface of the annular member 4, a storage recess 9 having a square cross section is formed with its axis directed toward the center of the annular member 4. The size of one side of the storage recess 9 is substantially the same as that of the through window 8, and a plurality of circumferential portions are provided in the circumferential direction at the same pitch as the through window 8 so as to correspond to the through window 8.

The locking member 5 is a square prism having a cross section of a slightly shorter side than that of the storage recess 9 and has a square cross section. The storage recess 9 can be moved in the radial direction of the annular member 4 and The tip portion is housed so as to protrude from the inner peripheral surface of the. Both ends of the distal end portion of the locking member 5 facing the circumferential direction of the annular member 4 gradually become narrower toward the radially inward direction of the annular member 4 to form an isosceles triangular shape having the foremost portion as an apex. Accordingly, inclined surfaces (inclined portions) 10 are formed at both ends of the distal end portion of the locking member 5 facing the circumferential direction of the annular member 4.

The compression coil spring 6 urges the locking member 5 radially inward of the annular member 4, and includes a bottom portion of the storage recess 9 and the locking member 5 stored in the storage recess 9. Are arranged between the housing recess 9 and the rear end face.
And the rear end face of the locking member 5.

In the telescopic member 1 having such a configuration,
When the storage recess 9 of the annular member 4 is located at a position corresponding to the through window 8 of the cylindrical member 3, the locking member 5 protrudes radially inward of the annular member 4 by the urging force of the compression coil spring 6, and the distal end is formed. The distal end of the locking member 5 is inserted into the peripheral groove 7 of the cylindrical member 2, thereby restricting the axial movement of the cylindrical member 2. In the restricted state, the inclined surface 10 of the locking member 5 is disposed to be substantially parallel to and opposed to the inclined surface 8a of the through window 8.

To adjust the length of the telescopic member 1 from the restricted state, when the annular member 4 is rotated in the direction of the arrow in FIG. 3, the inclined surface 10 of the locking member 5 penetrates as shown in FIG. By pressing the inclined surface 8a of the window 8 and the reaction force from the inclined surface 8a, the locking member 5 moves radially outward of the annular member 4 against the urging force of the compression coil spring 6, and finally As shown by a two-dot chain line in FIG.
And rides on the outer peripheral portion of the cylindrical member 3 to allow the cylindrical member 2 to move in the axial direction.

After the cylindrical member 2 is moved in the axial direction by a predetermined length, the annular member 4 is turned in the opposite direction to return the storage recess 9 to the original position, and the storage recess 9 is inserted into the through-hole of the cylindrical member 3. 8
In the same manner as described above, the distal end of the locking member 5 is inserted into the other circumferential groove 7 of the columnar member 2 to restrict the axial movement of the columnar member 2, thereby adjusting the length. Complete.

As is apparent from the above description, in the telescopic member 1 of this embodiment, when the length is adjusted by permitting and restricting the axial movement of the cylindrical member 2 with respect to the cylindrical member 3, Since it is sufficient to rotate the annular member 4 slightly, the length adjustment can be easily performed.

In the above-described embodiment, the case where a plurality of through-holes 8 are formed on the peripheral wall of the cylindrical member 3 is taken as an example. However, it is sufficient if at least one through-hole 8 is provided. It goes without saying that the same applies to the recess 9 and the locking member 5.

[0017]

As is apparent from the above description, according to the present invention, when the length of the shaft member is adjusted by permitting and restricting the axial movement of the shaft member, the annular member is slightly moved relative to the shaft member. It is sufficient to rotate only the length, so that the effect that the length can be adjusted easily can be obtained.

[Brief description of the drawings]

FIG. 1 is a front view of a telescopic member as an example of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III of FIG. 2;

FIG. 4 is an explanatory diagram for explaining a movement of a locking member when rotating an annular member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Telescopic member 2 ... Column member (bar member) 3 ... Cylindrical member (tubular member) 4 ... Annular member 5 ... Locking member 6 ... Compression coil spring (biasing member) 7 ... Peripheral groove 8 ... Through-window 8a ... Inclined surface (side edge of penetrating window facing in the circumferential direction) 9: Storage recess 10: Inclined surface (inclined portion)

Claims (1)

[Claims] 1. A rod member having a plurality of circumferential grooves formed at an outer peripheral portion along a circumferential direction at predetermined intervals in an axial direction, and the rod member is inserted so as to be relatively movable in the axial direction. A tubular member having a through window in a peripheral wall portion, an annular member rotatably inserted at a position corresponding to the through window of the tubular member, and having a storage recess in an inner peripheral portion, and an annular member in the storage recess. The distal end portion is housed so as to be movable in the radial direction of the member and protrude from the inner peripheral portion of the annular member, and the distal end portion gradually narrows inward in the radial direction of the annular member so that the annular shape of the distal end portion is reduced. A locking member having an inclined portion formed on a side portion facing the circumferential direction of the member, and a biasing member for biasing the locking member radially inward of the annular member, wherein the locking member includes: When the storage recess is at a position corresponding to the through window, the urging force of the urging member causes The distal end portion of the rod-shaped member protrudes radially inward and penetrates the through window, whereby the distal end portion is inserted into the circumferential groove of the rod member to regulate the axial movement of the rod member. When the annular member is rotated from the restricted state, the inclined portion presses the side edge of the through-hole facing in the circumferential direction, and the reaction force from the side edge causes the attachment to the outer side in the radial direction of the annular member. The rod member moves against the urging force of the urging member, and finally, the leading end portion climbs over the side edge of the through window and rides on the outer peripheral portion of the cylindrical member, thereby allowing relative movement of the rod member in the axial direction. A telescopic member.