Telescopic rod locking device

Abstract

The utility model relates to a telescopic rod locking device which comprises a screw fixedly connected with an inner pipe, a screw pipe capable of being arranged in an outer pipe and in threaded connection with the screw, and a plurality of expansion joints evenly formed in the circumferential direction of the screw pipe and penetrating through the lower end of the screw pipe. Different from the prior art, the screw rod has the taper with the thick upper end and the thin lower end, correspondingly, the inner wall of the screw tube also has the taper with the thick upper end and the thin lower end, and the taper of the screw rod is larger than that of the screw tube. Compared with the prior art, through the special taper design of the screw rod and the screw tube and the hemispherical protrusions on the outer wall of the screw tube, the locking stability and the operation convenience are improved through the combined action of the design. The structure is simple, locking is rapid and stable, the protrusions on the outer wall of the screw tube can enable pressure to be dispersed rapidly so that the screw tube is not prone to collapse, friction force is increased, and the slipping phenomenon is avoided.

Description

Technical Field

[0001] The utility model relates to a telescopic rod locking device and belongs to the technical field of daily necessities. Background Art

[0002] Telescopic poles are usually made up of multiple tubular parts, each of which has an outer diameter smaller than the inner diameter so that they can be nested together. These tubular parts can be extended or shortened by a telescoping mechanism. The telescopic pole locking device is usually used to ensure that the telescopic pole can remain stably in that position after being extended or retracted to a specific length. It is the core part of the telescopic pole, which ensures that the telescopic pole will not slide or move after reaching the desired length. Common locking mechanisms include: Screw lock: tighten or loosen the telescopic pole by rotating the parts. Wedge lock: uses a wedge or similar shaped part to apply pressure inside the telescopic pole to fix the current length. This type of lock is spring-loaded: uses the force of a spring to maintain the position of the telescopic pole. The user can release the spring through a button or other mechanism to adjust the length of the telescopic pole.

[0003] However, the existing wedge-shaped locking device has the defects of unstable locking and complicated operation, and the friction between the wedge-shaped block and the inner wall of the telescopic rod is small, which is easy to slip. Summary of the invention

[0004] In view of the above technical problem or one of the technical problems, the utility model provides a telescopic rod locking device, and the technical solution adopted is:

[0005] A telescopic rod locking device comprises a screw rod fixedly connected to an inner tube, a screw tube which can be placed in an outer tube and screwed to the screw rod, and a plurality of expansion joints penetrating the lower end of the screw tube are evenly arranged along the circumference of the screw tube; different from the prior art, the screw rod has a taper with a thick upper end and a thin lower end, and correspondingly, the inner wall of the screw tube also has a taper with a thick upper end and a thin lower end, but the taper of the screw rod is greater than that of the screw tube; and a hemispherical protrusion is arranged on the outer wall of the screw tube.

[0006] Furthermore, one of the expansion joints passes through the upper end of the spiral tube.

[0007] Furthermore, the diameter of the circumscribed circle of the protrusion is equal to or slightly smaller than the inner diameter of the outer tube and larger than the outer diameter of the inner tube.

[0008] Furthermore, a cylindrical stop is fixedly arranged at the upper end of the screw rod, and the diameter of the cylindrical stop is larger than the inner diameter of the upper end of the spiral tube.

[0009] Furthermore, the lower end of the screw rod is fixedly connected to a cylindrical connecting rod, and the connecting rod is interference fit with the inner tube.

[0010] Furthermore, a plurality of recesses entering into the connecting rod are punched on the circumferential outer wall of the outer tube.

[0011] Compared with the prior art, the utility model improves the stability of locking and the convenience of operation through the special taper design of the screw and the screw tube, as well as the hemispherical protrusion on the outer wall of the screw tube. The structure is simple, the locking is fast and stable, and the protrusion on the outer wall of the screw tube can quickly disperse the pressure so that it is not easy to collapse, increase the friction, and avoid slipping. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the utility model when it is applied to a telescopic tube.

[0013] Figure 2 yes Figure 1 Schematic diagram of the structure after hiding the outer tube.

[0014] Figure 3 It is a structural schematic diagram of the screw of the utility model.

[0015] Figure 4 It is a structural schematic diagram of the spiral tube of the utility model. DETAILED DESCRIPTION

[0016] The utility model is further described below in conjunction with the accompanying drawings.

[0017] like Figure 1-4The telescopic rod shown has two sections, including an inner tube 1 and an outer tube 2. The locking device includes a screw 3 fixed to the inner tube 1, a screw tube 4 that can be placed in the outer tube 2 and screwed to the screw 3, and four expansion joints 41 that penetrate the lower end of the screw tube 4 are evenly opened along the circumference of the screw tube 4, wherein one expansion joint 41 penetrates the upper end of the screw tube 4; in this way, the screw tube 4 can be conveniently sleeved on the screw 3 through the bidirectional expansion joint 41; the screw 3 has a taper with a thick upper end and a thin lower end, and its taper is 3° in this embodiment. Correspondingly, the inner wall of the screw tube 4 also has a taper with a thick upper end and a thin lower end, and its taper is 2° in this embodiment. The difference in taper can make the screw tube 2 gradually expand and lock with the outer tube 2 during the forward tightening process of the screw, and gradually shrink and separate from the outer tube 2 during the reverse tightening process, so that the inner tube 1 and the outer tube 2 can be stably maintained at that position after reaching a specific length. A hemispherical protrusion 42 is arranged on the outer wall of the spiral tube 4. The diameter of the circumscribed circle of the protrusion 42 is equal to or slightly smaller than the inner diameter of the outer tube 2 and larger than the outer diameter of the inner tube 1. The curved surface shape of the hemispherical protrusion 42 helps to evenly distribute the force to the entire surface of the protrusion. This is because the hemispherical structure can transfer the pressure to the surrounding when it is under pressure, rather than concentrating it on one point. This dispersion effect is similar to the structure of an eggshell. Although the eggshell is thin, it can withstand a pressure that is relatively large relative to its thickness due to its curved surface shape. When the hemispherical protrusion 42 contacts the inner wall of the outer tube, it is equivalent to point contact, and the pressure is greater. The friction formed between them helps to prevent slipping. Due to the hemispherical structure of the protrusion, even under the action of external force, it can ensure good contact and maintain friction, thereby improving the reliability of locking. Compared with a plane or a sharp edge, the hemispherical protrusion 42 is more able to reduce stress concentration in structure. When subjected to external force, the hemispherical structure can diffuse the stress outward, avoiding the generation of excessive stress concentration points at the root of the protrusion, thereby improving the overall strength of the structure. In short, the design of the hemispherical protrusion 42 achieves uniform force distribution, improved structural stability, enhanced anti-slip ability, enhanced energy absorption capacity, and reduced stress concentration by simulating the structural characteristics of eggshells in nature. These mechanisms work together to make the telescopic rod locking device more stable and durable when subjected to external force.

[0018] A cylindrical stopper 31 is fixed at the upper end of the screw rod 3, and the diameter of the cylindrical stopper 31 is larger than the inner diameter of the upper end of the screw tube 4. The presence of the cylindrical stopper ensures that the screw rod can stop being further tightened after being tightened to a certain position, thereby avoiding structural damage that may be caused by over-tightening. At the same time, the stopper provides a clear tightening end point, and the user can judge whether the locking position has been reached by feeling the resistance of the stopper.

[0019] The lower end of the screw rod 3 is fixedly connected to a cylindrical connecting rod 32, and the connecting rod 32 is interference fit with the inner tube 1. A plurality of recesses are punched on the circumferential outer wall of the outer tube 2 to enter the connecting rod 32. The design of the recess enables the outer tube to better fix the connecting rod, providing an additional anchor point, thereby increasing the overall stability of the locking device when tightening the screw rod. The recess can also serve as a mechanical locking point to prevent the connecting rod from moving during the tightening process.

Claims

1. A telescopic rod locking device, comprising a screw (3) fixedly connected to an inner tube (1), a screw tube (4) which can be placed in an outer tube (2) and screwed to the screw (3), and a plurality of expansion joints (41) extending through the lower end of the screw tube (4) are evenly arranged along the circumference of the screw tube (4); characterized in that The screw (3) has a taper with a thick upper end and a thin lower end, and the inner wall of the spiral tube (4) also has a taper with a thick upper end and a thin lower end, but the taper of the screw (3) is greater than the taper of the spiral tube (4); a hemispherical protrusion (42) is arranged on the outer wall of the spiral tube (4).

2. A telescopic rod locking device according to claim 1, characterized in that: One expansion joint (41) passes through the upper end of the spiral tube (4).

3. A telescopic rod locking device according to claim 1, characterized in that: The diameter of the circumscribed circle of the protrusion (42) is equal to or slightly smaller than the inner diameter of the outer tube (2) and larger than the outer diameter of the inner tube (1).

4. A telescopic rod locking device according to claim 1, characterized in that: A cylindrical stopper (31) is fixedly provided at the upper end of the screw rod (3), and the diameter of the cylindrical stopper (31) is larger than the inner diameter of the upper end of the spiral tube (4).

5. The telescopic rod locking device according to claim 1, characterized in that: The lower end of the screw rod (3) is fixedly connected to a cylindrical connecting rod (32), and the connecting rod (32) is interference fit with the inner tube (1).

6. A telescopic rod locking device according to claim 5, characterized in that: A plurality of recesses that enter into the connecting rod (32) are punched on the circumferential outer wall of the outer tube (2).

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