JP2570418Y2 - Length adjustment device for telescopic pipe members - Google Patents

Description

[Detailed description of the invention]

[0001]

In this invention, a large-diameter pipe member and a small-diameter pipe member are provided in a nested manner, whereby the pipe member expands and contracts, and the relative positions of the two at arbitrary positions are determined. More specifically, the present invention relates to a nested pipe member length adjusting device that regulates and adjusts the length of a nested pipe member, the nest member being capable of reliably restricting the axial movement of the pipe member even when an axial force is applied to the pipe member. The present invention relates to an apparatus for adjusting the length of a pipe member.

[0002]

2. Description of the Related Art A technique disclosed in Japanese Patent Application Laid-Open No. 53-74660 is one that can set the length of a nested pipe member composed of a large-diameter pipe and a small-diameter pipe at an arbitrary position. . In this technique, a shaft-shaped main body of a locking device inserted into a large-diameter pipe is fixed to an end of a small-diameter pipe, and the main body has at least a bulged portion that is substantially coaxial with the pipe axis of the small-diameter pipe. An eccentric shaft portion that is eccentric with respect to the eccentric shaft portion, and an eccentric ring whose large diameter and inner diameter are eccentric to each other is rotatably fitted to the eccentric shaft portion, and on the opposite side surface between the eccentric shaft and the enlarged diameter portion. The present invention relates to a telescopic rod locking device in which hooking claws are provided so as to be adjacent to each other.

In this conventional example, an eccentric shaft provided at an end of a small-diameter pipe and an eccentric ring fitted on the eccentric shaft are displaced in a radial direction by rotation of the small-diameter or large-diameter pipe, and the eccentric ring is eccentric. The state in which the large diameter pipe and the small diameter pipe are mutually stretched, in other words, the state in which the eccentric ring is crimped to the inner surface of the large diameter pipe by frictional force, and the large diameter pipe and the small diameter pipe are mutually Regulations are made so that they do not move.

[0004]

By the way, in such a conventional example, even if the relative position between the large-diameter pipe and the small-diameter pipe is regulated by frictional force and set to an arbitrary length, When a large force is applied in the direction, that is, a force that exceeds the frictional force, the shaft is displaced in the axial direction without being fully regulated.

[0005] The present invention has been made in view of such a situation of the prior art, and has as its object the nesting in which the set position, that is, the set length does not change even when a force is applied in the axial direction. An object of the present invention is to provide an apparatus for adjusting the length of a pipe member.

[0006]

In order to achieve the above-mentioned object, the present invention relates to a method of inserting a small-diameter pipe into a large-diameter pipe, and providing an eccentric shaft at a portion of the inserted small-diameter pipe which overlaps the large-diameter pipe. An annular member is inserted into the shaft, and the annular member is moved between the eccentric shaft and the inner surface of the large-diameter pipe so as to stretch between the eccentric shaft and the inner surface to generate a frictional force. In a nested pipe member length adjusting device that regulates the length of a pipe member by regulating the relative position with respect to the diameter pipe by the annular member, a small-diameter or large-diameter pipe is axially moved to move the annular member and the large-diameter pipe together. The eccentric shaft is formed with a tapered surface capable of generating a frictional force enough to make it impossible to move between the small diameter pipe and the large diameter pipe by increasing the frictional force with the inner surface of the large diameter pipe.

[0007]

According to the above-mentioned means, one or both of the tubes are rotated when the large-diameter tube and the small-diameter tube have a desired length. As a result, the annular member rotates together with the eccentric shaft, and the outer surface of the annular member contacts the inner surface of the large-diameter tube and further presses to generate a frictional force, thereby regulating the positions of the two members. When a force is applied in the axial direction in such a regulated state, and the relative positions of the two shift in the axial direction, for example, in the direction of shortening, the annular member shifts toward the base side of the tapered eccentric shaft, and further moves outward. Is displaced. As a result, the frictional force becomes larger, and the inner surface of the large-diameter tube is pressed with a larger force, and the large-diameter tube is pushed and spread, and the relative movement between the large-diameter tube and the small-diameter tube is increased with a larger force. It will be regulated. In this way, the positions of both are reliably regulated.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. In the following description, components that can be regarded as equivalent in each embodiment are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 is a perspective view of a main part showing a small diameter pipe and a top of a length adjusting device for a pipe member according to a first embodiment of the present invention.
2A and 2B illustrate the state of the small diameter tube and the top. FIG. 2A is a side view of the small diameter tube, and FIG. 2B is a plan view of the top. In these figures, an eccentric shaft 3 is protruded from an end cap 2 of a small-diameter tube 1 in an eccentric state in parallel with the axis of the small-diameter tube 1, and a flange 4 is provided at a tip thereof perpendicular to the axis. ing. The eccentric shaft 3 is formed such that a tapered taper is formed on the outer surface of the small-diameter tube 1 so that the side on which the flange 4 is attached is thin and the end cap 2 side of the small-diameter tube 1 is thick. Further, a stopper 5 for regulating a rotational position of a frame 6 described later is provided on an outer peripheral portion of the flange 4 so as to project in a circumferential direction.

The top 6 is substantially disc-shaped, and has a notch 7 for externally fitting the eccentric shaft 3 from a part of the outer periphery to the inside.
Are formed through the center of the top 6 to a position closer to the outer peripheral portion. In addition, a projection 9 which comes into contact with the stopper 5 and regulates the rotation position is provided on the end face of the notch 7 near the deepest portion 8 in parallel with the axis. A notch 10 is formed in the deepest portion 8 of the notch 7 so as to be elastically deformable.
In addition, although not shown, instead of this notch 10,
The position may be hinged so that the front end of the notch 7 can be freely opened and closed.

The frame 6 constructed as described above has a notch 7
Is inserted into the eccentric shaft 3 in a direction perpendicular to the axis of the eccentric shaft 3, the notch 7 is set to have a dimension substantially matching the width of a small diameter corresponding to the tip of the eccentric shaft 3, and the top 6 is in a free state. , The eccentric shaft 3 is rotatable only on the tip 3a side. When displaced toward the base 3b of the eccentric shaft 3, that is, toward the end cap 2 of the small-diameter tube 1, the eccentric shaft 3 is pushed and spread by the taper, and cannot rotate.

With this configuration, the top 6 can be connected to the eccentric shaft 3.
As described above, the end cap 2 of the small-diameter pipe 1 is inserted into a large-diameter pipe 11 having an inner diameter slightly larger than the end cap 2 of the small-diameter pipe 1 as shown in FIG. Adjusting the lengths of the large-diameter pipe 11 and the small-diameter pipe 1 to rotate the small-diameter pipe 1 with respect to the large-diameter pipe 11, in other words, twisting both to relatively rotate both pieces, Is rotated while being fitted to the eccentric shaft 3. Then, the top 6 and the inner surface 1 of the large-diameter pipe 11
2 abuts, the top 6 moves relatively to the opening side of the notch 7 along the notch 7, and when the projection 9 of the top 6 comes into contact with the stopper 5 and its position is regulated, the top 6 The portion farthest from the eccentric center of No. 6 strongly hits the inner surface of the large-diameter pipe 11, and a large frictional force is generated. When the rotation becomes impossible, the frictional force becomes sufficient to regulate the relative position between the small-diameter tube 1 and the large-diameter tube 11, and the length can be defined at that position.

With the length defined in this way,
When a force is applied in the axial direction and both contract,
The top 6 moves to the base side of the eccentric shaft 3 according to the amount of contraction, and the top 6 is spread out as shown in FIG. Diameter pipe 1
When the large-diameter pipe 11 has any elasticity, the large-diameter pipe 11 is brought into contact with the inner surface 12 and the top 6 is stretched between the eccentric shaft 3 and the inner surface 12. , And the relative movement between the two is prevented. In this way, the length of the pipe member is reliably defined.

In the first embodiment, as shown in FIGS. 1 and 2 (a), the taper having the same gradient is formed from the base 3b of the eccentric shaft 3 toward the tip 3a. If the small-diameter tube 1 and the large-diameter tube 11 are unintentionally misaligned in the axial direction, the top 6 moves to the base 3b side of the eccentric shaft 3 and the diameter of the top 6 increases. Become. When the diameter of the top 6 is increased in this way, the state where the eccentric shaft 3 and the inner surface 12 of the large diameter tube 11 are in a state of being stretched as described above, and the expansion / contraction operation of the small diameter tube 1 and the large diameter tube 11 is hindered. ,
The relative position of both is regulated. Therefore, as shown in FIG. 3A as a second embodiment, a cylindrical portion 3c may be formed on the tip 3a side of the eccentric shaft 3 so that the eccentric shaft 3 can be moved within this range. As a result, even if the top 6 moves, even if the top 6 moves, the top 6 immediately moves at the tapered portion.
During this time, the top 6 rotates in the circumferential direction to prevent the eccentric shaft 3 and the inner surface 12 of the large-diameter pipe 11 from being in a state of tension, thereby avoiding the above-described inconvenience. The risk of occurrence is very low. The notch 7 of the top 6 has a taper 7 having the same inclination as the tapered portion of the eccentric shaft 3.
If a is formed, the contact area becomes large when the top 6 moves to the tapered portion, the frictional force generated from the contact portion becomes larger, and the fixing force of the small diameter pipe 1 and the large diameter pipe 11 by the top 6 is also large. As a result, the positioning of the two members, in other words, the fixing can be performed more reliably. Forming the taper 7a in the notch 7 of the top 6 can be similarly performed in the examples shown in FIGS. 1 and 2 and has the same effect.

When the cylinder and the taper are combined in this manner, the above-mentioned phenomenon hardly occurs. However, assuming a case, as shown in the third embodiment shown in FIG. A groove 3d in the circumferential direction between 3c and the tapered portion,
Further, protrusions 7b which can be loosely inserted into the grooves 3d are respectively formed in the notches 7 of the top 6, so that the relative position between the small-diameter tube 1 and the large-diameter tube 11 is not restricted, that is, both are fixed to a desired length. If not, the projection 7b is loosely inserted into the groove 3d, and the small-diameter tube 1 and the large-diameter tube 11 are relatively rotated at a desired length position to make the projection as described above. In this case, the top 6 depends on the amount of eccentricity of the eccentric shaft 3.
The projection 7b is separated from the groove 3d, and the top 6 is movable in the axial direction. Therefore, when both are displaced by receiving an external force in the axial direction in this state, the top 6 further spreads due to the tapered portion of the eccentric shaft 3 and generates a strong frictional force. The relative movement between them is regulated with even greater force. Therefore, when the projection 7b and the groove 3d are combined in this manner, the small-diameter pipe 1 and the large-diameter pipe 1
1 will not be locked in an unintended position.

It is needless to say that the same effect can be obtained by the reverse combination of the projection 7b and the groove 3d.

[0017]

As is apparent from the above description, the frictional force between the annular member and the inner surface of the large-diameter pipe is increased by the axial movement to move between the small-diameter pipe and the large-diameter pipe. According to this invention, a tapered surface capable of generating a frictional force that makes it impossible is formed on the eccentric shaft, and the frictional force is further increased by expanding the annular member by the tapered surface, so that a small diameter pipe and a large diameter The relative movement of the pipes can be reliably restricted, and the set length between the two does not change unintentionally.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state of an eccentric shaft and a top of a length adjusting device of a telescopic pipe member according to a first embodiment of the present invention.

FIGS. 2A and 2B are diagrams showing a state of an eccentric shaft and a top of a telescopic pipe length adjusting device according to a first embodiment, wherein FIG. 2A is a side view showing an eccentric shaft side, and FIG. It is a top view.

FIG. 3 is a view showing an eccentric shaft and a top of a telescopic pipe member length adjusting device according to a second embodiment of the present invention;
(A) is a side view showing the eccentric shaft side, and (b) is a longitudinal sectional view showing the top side.

FIGS. 4A and 4B are diagrams showing a state of an eccentric shaft and a top of a pipe member length adjusting device according to a third embodiment of the present invention, wherein FIG. 4A is a side view showing an eccentric shaft side, and FIG. FIG.

FIG. 5 is a partially cut-away side view showing a state in which a top is stretched between a small-diameter pipe and a large-diameter pipe, and FIG.
(B) shows a state when a force is applied in the axial direction.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Small diameter pipe 2 End cap 3 Eccentric shaft 3a Tip 3b Base 3c Column part 3d Groove 6 Frame 7 Notch 11 Large diameter pipe 12 Inner surface

Claims (1)

(57) [Scope of request for utility model registration] A small-diameter pipe is inserted into a large-diameter pipe, an eccentric shaft is provided at a portion of the inserted small-diameter pipe that overlaps the large-diameter pipe, and an annular member is inserted into the eccentric shaft. The pipe is moved between the eccentric shaft and the inner surface of the large-diameter pipe so as to stretch between the eccentric shaft and the inner surface to generate a frictional force and regulated by the annular member to adjust the length of the pipe member. In the length adjusting device for a nested pipe member, the frictional force between the annular member and the inner surface of the large-diameter pipe is increased by moving the small-diameter pipe or the large-diameter pipe in the axial direction. A length adjusting device for a nested pipe member, wherein a tapered surface capable of generating a frictional force sufficient to make it impossible to move between the pipe and the diameter pipe is formed on the eccentric shaft.