TWI729360B - Caster device - Google Patents

Abstract

A caster device includes a base that can be pressed down and moved downward, two casters, two friction wheels, and two protruding teeth sets. Each caster includes an inner ring surface, and the inner ring surface is formed with a plurality of teeth arranged in a circle. The friction wheels are respectively installed on the left and right sides of the bottom of the base. The protruding teeth groups are respectively located beside the friction wheels. Each protruding tooth group includes a plurality of protruding protruding teeth which can be engaged with the corresponding tooth portions of the inner ring surface. The protruding teeth group and the friction wheels can descend when the base is pressed down, and then press the teeth of the inner ring surface, so that the casters are fixed and will not rotate arbitrarily. The chair or table to which the present invention is applied is fixed in place.

Description

Caster device

The invention relates to a caster device, in particular to a caster device that can be stopped after being pressed down.

There are many types of chairs. In order to facilitate the movement of the chair, one type of chair includes a chair body for the user to sit on, and several casters arranged at the bottom of the chair body. The chair body can be driven to move through the rotation of the casters. The chairs with casters have developed different functions in response to different usage needs. Take an office chair as an example. Generally, for convenience of movement, when the user sits on the office chair, the casters can still rotate freely, so the user can still move the chair back and forth while sitting on the office chair.

Another use requirement is that when the user sits on the chair, the chair is fixed in place. The casters of this chair need to have a special locking positioning structure, so that the user can automatically fix the casters after sitting on the chair. It does not rotate arbitrarily, achieving the effect of positioning the chair in place. For example, young children riding on such a chair can improve safety. The present invention is aimed at researching and improving the caster that can be positioned and stopped after being pressed down.

Therefore, the purpose of the present invention is to provide a caster device that is innovative in structure, can be stopped and positioned after being pressed down, and has high positioning stability.

Therefore, the caster device of the present invention includes a base that can be pressed down and moved downward, two casters, an elastic member, two friction wheels, and two sets of protruding teeth.

The casters are rotatably installed on the left and right sides of the base. Each caster includes an inner ring surface surrounding its own central axis, and the inner ring surface is formed with a plurality of teeth arranged in a circle. The elastic member is installed in the base and used to provide a constant upward elastic restoring force of the base. The friction wheels are respectively installed on the left and right sides of the bottom of the base, and respectively face the teeth of the inner ring surfaces. The protruding tooth groups are spaced apart from the left and right and are located beside the friction wheels, and respectively face the tooth portions of the inner ring surfaces. Each protruding tooth group includes a number of protruding downward and corresponding inner ring surfaces. The protruding teeth that engage with the teeth. The protruding teeth group and the friction wheels can descend when the base is pressed down, and then press the teeth of the inner ring surface, so that the casters are fixed and will not rotate freely.

The effect of the present invention is that through the friction wheels and the protruding teeth sets, the teeth of the inner ring surfaces of the casters can be pressed and fixed when the base is pressed down, so that the casters can be pressed and fixed. Fix the chair or table to which the present invention is applied in the original place. The protruding teeth groups can disperse the force applied to the friction wheels by the teeth of the casters, which helps reduce friction wheel wear and increase the service life of the friction wheels. The protruding teeth set and the friction wheel are matched to provide a double pressure surface, which enlarges the pressure contact area with each caster, so that the caster is more stable when positioning.

Referring to Figures 1 and 2, an embodiment of the caster device of the present invention can be applied to furniture such as tables, chairs, etc., and is suitable for mounting a coupling rod 1 by which the coupling rod 1 is assembled on the bottom of the table body or the chair body. In this embodiment, it is applied to a chair as an example. The caster device includes a base 2, a mounting post 3, an elastic member 4, a shaft 5, two casters 6, two friction wheels 7, and two protruding teeth set 8.

Referring to FIGS. 2, 3, and 4, the base 2 is made of, for example, but not limited to, plastic material, and includes an inserting portion 21 suitable for inserting and connecting the connecting rod 1 and a connecting portion 22 connected to the inserting portion 21 . The coupling portion 22 has a top wall 221 and two side walls 222 opposite to each other and extending downward from the periphery of the top wall 221. The top wall 221 and the side walls 222 jointly define a mounting hole 220 with an opening facing downward. Each side wall 222 has a through hole 223 extending from the inner wall surface to the outer wall surface of the side wall 222.

The mounting post 3 extends into the mounting hole 220 from bottom to top, and includes a post body 31 and an extension body 32 extending upward from the top surface of the post body 31. The column body 31 has a through hole 311 corresponding to the positions of the through holes 223 of the side walls 222.

The elastic member 4 is located in the mounting hole 220 of the base 2 and surrounds the extension 32 of the mounting post 3. The elastic member 4 is a compressible spring, located between the top surface of the column body 31 of the mounting column 3 and the top wall 221 of the coupling portion 22, and is used to provide the base 2 with a constant upward elastic restoring force.

The shaft 5 extends laterally through the through holes 223 of the side walls 222 and the through holes 311 of the column body 31, and the left and right ends are connected to the casters 6 respectively.

The casters 6 are spaced left and right, and are rotatably installed on the left and right sides of the base 2 through the shaft 5. Each caster 6 includes an inner ring surface 61 surrounding its own central axis (also equivalent to surrounding the connecting shaft 5), and the inner ring surface 61 is formed with a plurality of teeth 62 arranged in a circle.

The friction wheels 7 are respectively installed on the left and right sides of the bottom of the joint 22 of the base 2 and face the teeth 62 of the inner ring surfaces 61 respectively. The friction wheels 7 are made of rubber, with certain hardness and sufficient elasticity, and can return to their original shape after being squeezed and deformed. Each friction wheel 7 has an arc shape and a friction surface 71 for contacting the teeth 62.

The protruding tooth groups 8 are, for example, but not limited to, plastic materials, and are spaced apart from each other and located beside the friction wheels 7 respectively. Specifically, the protruding tooth groups 8 of this embodiment are located between the friction wheels 7 and respectively face the tooth portions 62 of the inner ring surfaces 61. Each protruding tooth set 8 includes a plurality of protruding teeth 81 integrally connected to the bottom of the coupling portion 22 of the base 2. The protruding teeth 81 extend in the left-right direction and are arranged in the front-to-back direction, and protrude downward to be able to correspond to the The teeth 62 of the ring surface 61 engage with each other.

Referring to FIGS. 3 to 5, when the present invention is used, in a normal state, the casters 6 can rotate freely to drive the base 2 and other components to move. When the base 2 is pressed and moved downward, the top wall 221 presses the elastic member 4, and the elastic member 4 compresses and accumulates an elastic restoring force. As the base 2 is pressed down, the protruding teeth groups 8 and the friction wheels 7 descend to the position shown in FIG. 5, and then press the teeth 62 of the inner ring surfaces 61. At this time, the protruding teeth groups The protruding teeth 81 of 8 engage with some of the teeth 62, and the friction wheels 7 are tightly pressed against some of the teeth 62 due to the elasticity of the rubber material, thereby making The casters 6 are fixed and will not rotate arbitrarily. When the amount of downward pressure applied to the base 2 is released, the base 2 is pushed by the upward elastic restoring force of the elastic member 4, and the base 2 then moves upward and drives the set of teeth 8 and the friction wheel 7 to return. To the positions shown in Figures 3 and 4, the casters 6 can now rotate freely.

Taking a chair as an example, when the user is not riding on the chair, the casters 6 can rotate freely to drive the chair body to move. When the user sits on the chair, the weight of the user acts on the base 2 through the chair body and the coupling rod 1, and the base 2 is thus lowered, and the friction wheels 7 and the set of teeth 8 are also lowered The teeth 62 are tightly pressed and engaged so that the casters 6 are fixed, and the chair will not move arbitrarily. When the user gets up and leaves the chair, the elastic member 4 pushes the base 2 upward to return to the position shown in FIGS. 3 and 4, and the casters 6 can rotate freely to drive the chair body to move.

It is worth mentioning that in the natural state as shown in Figures 3 and 4, the height position of a bottom edge (lowest point) 70 of each friction wheel 7 is lower than a bottom edge (lowest point) of each protruding tooth group 8. ) 80, so when the friction wheel 7 and the protruding tooth group 8 descend from the position of FIG. 4 to the position of FIG. 5, the friction wheel 7 contacts the teeth 62 before the protruding tooth group 8, and then the friction wheel 7 After being squeezed downward and slightly deformed, the protruding teeth groups 8 then contact and engage the teeth 62. The advantage of this design is that because the friction wheel 7 is elastic and softer than the tooth set 8, the friction wheel 7 first buffers the amount of downward pressure, so as to avoid the tooth set 8 and the teeth 62 from directly hitting hard.

In summary, through the friction wheels 7 and the set of protruding teeth 8, the teeth 62 of the inner ring surfaces 61 of the casters 6 can be pressed against the casters 6 when the base 2 is pressed down. By pressing and fixing, the chair or table to which the present invention is applied can be fixed in place. Moreover, the double pressing structure of the lug set 8 and the friction wheel 7 has the following two advantages: First, the teeth 62 of the caster 6 can be dispersed through the lug set 8 to disperse the force applied to the friction wheel 7, which helps To reduce the wear of the friction wheel 7 and increase the service life of the friction wheel 7. Secondly, the protruding teeth group 8 and the friction wheel 7 are matched to provide a double pressing surface, which enlarges the pressing contact area with each caster 6 so that the caster 6 can be more stably fixed in place. Especially when the user sits on a chair and wants to move the chair, the protruding teeth group 8 can share the friction loss caused by the possible relative movement of the friction wheel 7 due to the possible relative movement of the teeth 62 of the caster 6 on the one hand, and also because of the protruding teeth. The stable effect of the double pressing of the tooth set 8 and the friction wheel 7 prevents the caster 6 from being moved.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited by this, all simple equivalent changes and modifications made in accordance with the scope of the patent application of the present invention and the content of the patent specification still belong to This invention patent covers the scope.

1: Combination lever 2: pedestal 21: Insertion 22: Joint 220: mounting hole 221: top wall 222: Sidewall 223: Through Hole 3: Mounting post 31: Column body 311: Perforation 32: Extension 4: Elastic parts 5: Connecting shaft 6: casters 61: inner ring surface 62: Teeth 7: Friction wheel 70: bottom edge 71: friction surface 8: tooth group 80: bottom edge 81: protruding teeth

Other features and effects of the present invention will be clearly presented in the embodiments with reference to the drawings, in which: Figure 1 is a three-dimensional assembly view of an embodiment of the caster device of the present invention; Figure 2 is a three-dimensional exploded view of the embodiment; Figure 3 is a front cross-sectional view of the embodiment; Figure 4 is a side sectional view of the embodiment; and Fig. 5 is a cross-sectional view similar to Fig. 4, illustrating that a base is lowered in this embodiment, and a friction wheel and a protruding tooth set abut against several teeth on an inner ring surface of a caster.

1: Combination lever

2: pedestal

21: Insertion

22: Joint

220: mounting hole

221: top wall

222: Sidewall

223: Through Hole

3: Mounting post

31: Column body

311: Perforation

32: Extension

4: Elastic parts

5: Connecting shaft

6: casters

61: inner ring surface

62: Teeth

7: Friction wheel

70: bottom edge

71: friction surface

8: tooth group

80: bottom edge

81: protruding teeth

Claims (7)

A caster device includes: a base that can be pressed down to move downward; two casters are rotatably installed on the left and right sides of the base, each caster includes an inner ring surface around its own central axis, The inner ring surface is formed with a plurality of teeth arranged in a circle; an elastic member is installed in the base and used to provide a constant upward elastic restoring force of the base; two friction wheels are respectively installed on the base The left and right sides of the bottom, respectively facing the teeth of the inner ring surface; and two sets of protruding teeth, which are spaced apart from each other and are located beside the friction wheels, and respectively face the teeth of the inner ring surface Each protruding tooth set includes a plurality of protruding teeth that can be engaged with the teeth of the corresponding inner ring surface. The protruding teeth set and the friction wheels can be pressed down on the base Follow the time to descend, and then press against the teeth of the inner ring surface, so that the casters are fixed and will not rotate freely. Among them, the height of a bottom edge of each friction wheel is lower than that of each set of protruding teeth. The height position of a bottom edge. The caster device according to claim 1, wherein the protruding teeth of each protruding teeth group extend in a left-right direction and are arranged in a front-to-back direction. The caster device according to claim 1, wherein the sets of protruding teeth are located between the friction wheels. The caster device according to claim 1, wherein the sets of protruding teeth are integrally connected to the bottom of the base. The caster device according to claim 1, wherein the friction wheels are made of rubber, and each friction wheel has an arc shape and is used to contact the friction surface of the teeth. The caster device according to claim 1, wherein the base includes a coupling portion, the coupling portion has a top wall, and two side walls opposite to each other and extending downward from the periphery of the top wall, the top wall and the top wall The side walls jointly define a mounting hole with an opening facing downwards. The caster device further includes a mounting post extending into the mounting hole from bottom to top, and the elastic member is located between the mounting post and the top wall of the coupling part. The caster device according to claim 6, wherein each side wall of the coupling portion has a through hole extending from the inner wall surface to the outer wall surface of the side wall, the mounting post has a through hole corresponding to the position of the through hole, the The caster device also includes a shaft that extends transversely through the through holes and the perforation, and the left and right ends are respectively connected to the casters.

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