Telescoping universal roller assembly and chair
By employing a dual-guide and double-layer slewing bearing structure, the problems of wheel jamming and slewing instability during extension and retraction are solved, achieving stability and convenience in chair movement.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- HEBEI HONGPAI FURNITURE CO LTD
- Filing Date
- 2025-08-22
- Publication Date
- 2026-06-12
AI Technical Summary
In the existing technology, the longitudinal guiding strength of the rollers is insufficient, which can easily cause jamming during the extension and retraction process. The slewing bearing is not stable enough, which causes the rollers to wobble during the movement of the chair.
The design employs a dual-guide structure and a double-layer slewing bearing. The guide is achieved by the rod part cooperating with the through hole and the seat part cooperating with the inner wall of the housing. The double-layer slewing bearing structure, composed of the first and second rolling element groups, ensures the guiding strength and rotational stability of the roller during the extension and retraction process.
The guide strength of the rollers during the extension and retraction process has been improved to avoid jamming and to ensure the rotational stability of the chair during movement, preventing the rollers from wobble.
Smart Images
Figure CN224344553U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of furniture technology, and in particular to a retractable universal caster assembly and a chair. Background Technology
[0002] The ease of movement of chairs is increasingly important to users. Designers have incorporated springs and rollers into the bottom of the chair legs. When a user sits on the seat, the user's weight overcomes the spring's elastic force, causing the rollers to retract into the legs. When the user gets up, the spring's elastic force pushes the rollers out of the legs, facilitating chair movement. For example, patent CN223136877U discloses a gravity-locked pulley structure that uses a spring positioned between the inner wall of the compression chamber and the outer wall of the mounting base to achieve pulley extension and retraction. Universal movement is achieved through a rolling connection between a first ball bearing and a ball ring formed by multiple second balls distributed within a concave ring. Another example is a novel chair disclosed in patent CN202365321U, which uses a spring positioned between the support sleeve and connecting rod to achieve caster extension and retraction. The outer ring of the bearing is supported by a protrusion on the support sleeve, and the inner ring is engaged between the upper end of the connecting rod and the caster mounting bracket, thus enabling universal movement.
[0003] However, the longitudinal guiding strength of the rollers in the existing technology is insufficient, which can easily cause jamming during the extension and retraction process. In addition, the rotational bearing stability of the rollers is insufficient, which can easily cause the rollers to wobble during the movement of the chair. Utility Model Content
[0004] This utility model provides a retractable universal roller assembly and a chair.
[0005] Specifically, this utility model is achieved through the following technical solution:
[0006] In a first aspect, this utility model provides a retractable universal roller assembly, including a housing and a spring, a sliding body, a rotating body, and a roller disposed within the housing. The roller is rotatably connected to the bottom of the rotating body, and the rotating body is rotatably connected to the bottom of the sliding body. The spring is disposed between the sliding body and the top of the housing. A through hole is formed on the top of the housing. The sliding body is provided with a rod, a seat surrounding the outer periphery of the rod, and a disc disposed at the bottom end of the rod. The rod matches the shape of the through hole, and the seat matches the shape of the inner wall of the housing. The retractable universal roller assembly also includes a first rolling body group and a second rolling body group. The top of the rotating body is disposed between the seat and the disc. The first rolling body group is rotatably supported between the seat and the top of the rotating body, and the second rolling body group is rotatably supported between the top of the rotating body and the disc. The rotation radius of the second rolling body group is smaller than that of the first rolling body group, and the rotation axis of the roller is located at an eccentric position at the rotation center of the rotating body.
[0007] In some embodiments, the top of the rod is provided with a horizontally extending pin hole, a pin passes through the pin hole and at least one end of the pin extends out of the pin hole.
[0008] In some embodiments, a downwardly extending retaining ring is provided at the top of the housing in the outer edge region of the through hole, and the top of the spring is sleeved on the outside of the retaining ring.
[0009] In some embodiments, the seat is bowl-shaped with the opening facing upwards, and the bottom of the spring is supported within the bowl-shaped cavity.
[0010] In some embodiments, the bottom of the bowl shape is provided with an upwardly extending rib in the outer edge region of the rod, and the bottom of the spring is sleeved on the outside of the rib.
[0011] In some embodiments, both the first rolling element group and the second rolling element group are composed of balls, and the diameter of the balls in the first rolling element group is larger than that in the second rolling element group.
[0012] In some embodiments, the rotating body is disposed around the outer periphery of the rod and forms a sealing fit with the outer periphery of the rod.
[0013] In some embodiments, the rotating body is in the shape of a bowl with its opening facing downwards.
[0014] In some embodiments, each of the two sidewalls of the bowl shape is provided with a downwardly extending lug, and the roller's axis of rotation is disposed on the pair of lugs, wherein the pair of lugs are constricted towards each other at one end in an eccentric direction toward the roller's axis of rotation.
[0015] Secondly, this utility model provides a chair, including legs and the retractable universal roller assembly described in the first aspect, wherein the housing of the retractable universal roller assembly is disposed inside the legs or at the bottom of the legs.
[0016] According to the embodiments of this utility model, the guide is provided by the cooperation between the rod and the through hole, and by the cooperation between the seat and the inner wall of the housing, providing double guide support for the roller during the extension and retraction process. This improves the longitudinal guiding strength of the roller and avoids jamming during the extension and retraction of the roller. Through the double-layer slewing bearing structure composed of the first rolling element group and the second rolling element group, the load force transmitted by the roller located in the eccentric position can be mainly borne by the first rolling element group with a larger slewing radius. The slewing body will tilt under the load of the first rolling element group. The second rolling element group with a smaller slewing radius is used to correct the tilt of the slewing body, ensuring the slewing stability of the roller and avoiding roller wobble during the movement of the chair.
[0017] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description
[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0019] Figure 1 This is a schematic diagram of the retractable universal roller assembly in an embodiment of the present invention.
[0020] Figure 2 This is a top view of the retractable universal roller assembly in an exploded state according to an embodiment of the present invention;
[0021] Figure 3 This is a schematic diagram of a portion of the retractable universal roller assembly structure in one embodiment of the present invention;
[0022] Figure 4 This is a bottom view of a portion of the retractable universal roller assembly structure in one embodiment of the present invention;
[0023] Figure 5 This is a cross-sectional view of a retractable universal roller assembly according to an embodiment of the present invention.
[0024] Figure label:
[0025] 10: Housing; 11: Protrusion; 12: Boss; 13: Through hole; 14: Retaining ring; 20: Sliding body; 21: Rod; 211: Pin hole; 22: Seat; 23: Rib; 24: Disc; 30: Rotating body; 31: Support ear; 311: Narrowing part; 40: Roller; 50: Spring; 61: First rolling element group; 62: Second rolling element group. Detailed Implementation
[0026] The present invention will now be discussed with reference to several embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and thus implement the present invention, and are not intended to imply any limitation on the scope of the present invention.
[0027] As used herein, the term "comprising" and its variations are to be interpreted as open-ended terms meaning "including but not limited to"; the terms "embodiment" and "one embodiment" are to be interpreted as "at least one embodiment"; the term "another embodiment" is to be interpreted as "at least one other embodiment"; the terms "first," "second," etc., may refer to different or the same objects; the term "setup" is not limited to direct or indirect connections, nor to specific connection methods. Other explicit and implicit definitions may also be included below.
[0028] Specific numerical values or ranges may be mentioned in the following description. It should be understood that these values and ranges are merely exemplary and may be helpful in putting the ideas of this invention into practice. However, the description of these examples is not intended to limit the scope of this invention in any way. These values or ranges may be set differently depending on the specific application scenario and requirements.
[0029] The directional terms “top”, “bottom”, “upper”, and “lower” used in this utility model refer to the relative reference positions during the use of the retractable universal roller assembly.
[0030] As mentioned above, in the prior art, the rollers are prone to jamming during extension and retraction, and the rollers are also prone to wobble during chair movement. The retractable universal roller assembly and chair proposed in the embodiments of this utility model at least partially solve the above problems. The following will refer to... Figure 1 to- Figure 5 This describes the structure and working principle of the retractable universal caster assembly and chair according to this utility model. For example... Figures 1-5 As shown, the retractable universal roller assembly of this utility model generally includes a housing, a spring, a slider, a rotating body, a roller, a first rolling body group, and a second rolling body group. The housing is used to internally connect the spring, slider, rotating body, roller, first rolling body group, and second rolling body group, and is installed at the bottom of the chair leg. The slider is used to drive the rotating body, roller, first rolling body group, and second rolling body group to slide up and down as a whole within the housing. The rotating body is used to drive the roller, first rolling body group, and second rolling body group to perform 360-degree free rotation relative to the housing and slider. The roller contacts the ground to support the movement of the retractable universal roller assembly and the chair.
[0031] In one embodiment, the outer contour of the housing can be of any shape, as long as it can be stably installed inside the chair leg or at the bottom of the leg. For example, such as... Figure 1 As shown, the outer contour of the shell is a regular square, and correspondingly, the inner cavity of the chair leg is also a regular square, which facilitates the insertion of the shell into the inner cavity of the chair leg, and the protrusions on the outside of the shell achieve a tight connection with the inner cavity of the chair leg. In other examples, the outer shell can also be circular, hexagonal, or other shapes.
[0032] In one embodiment, a boss is provided on the outer edge of the bottom of the housing. When the entire housing is inserted into the inner cavity of the chair leg, the top of the boss abuts against the bottom of the chair leg to limit the vertical movement between the housing and the chair leg.
[0033] In another embodiment, the housing can also be installed at the bottom of the chair legs. In this case, the user can still see the exterior of the housing even when the wheels are retracted into the housing.
[0034] The shell has a closed top and open bottom structure. A through hole is provided in the central area of the top of the shell. The inner contour of the through hole matches the outer contour of the rod, so that the rod can pass through the through hole and move freely in the vertical direction. During the free movement, the through hole can provide stable support for the rod in all directions, prevent the rod from shaking during the movement, and ensure the guiding strength of the rod's vertical movement.
[0035] The sliding body consists of a rod, a seat, and a disc. The seat is positioned between the top and bottom of the rod and is shaped to surround the outer periphery of the rod. The seat houses the spring, and its shape matches the inner wall of the housing. This allows the inner wall of the housing to provide stable support to the seat in all directions as the rod moves freely up and down, achieving a dual guiding function for the rod and ensuring the guiding strength of its vertical movement. For example,... Figures 1-5 As shown, both the outer periphery of the seat and the inner wall of the shell are circular, allowing the sliding part to rotate relative to the shell during its up-and-down movement. In this case, during chair use, the spring remains continuously compressed by the weight of the chair body. The frictional force generated by the pressure of the spring's top and bottom against the top of the shell and the bottom of the seat provides damping for the rotational movement of the sliding part, ensuring that the rollers steer primarily by the rotation of the rotating part during chair movement. In other examples, the outer periphery of the seat and the inner wall of the shell are quadrilateral, hexagonal, or other shapes with edges, restricting the sliding part from rotating relative to the shell and ensuring that the rollers steer primarily by the rotation of the rotating part during chair movement.
[0036] The bottom end of the rod is provided with a disc. For example, the disc and the rod can be connected as one piece by screwing, riveting, or welding. There is a gap between the top of the disc and the bottom of the seat, which allows the rotating body to be inserted and forms a double-layer annular groove with the rotating body. The first rolling element group and the second rolling element group are respectively installed in the double-layer annular groove to form a double-layer rotary support structure.
[0037] Specifically, the main structure of the rotating body is disc-shaped, with annular grooves formed at both the top and bottom of the disc-shaped main structure. Corresponding annular grooves are also formed at the bottom of the seat and the bottom of the disc. Multiple rollers from the first and second rolling element groups are arranged within these annular grooves, forming a double-layer rotating support structure. For example, the rollers can be ball bearings, tapered rollers, or cylindrical rollers.
[0038] In this embodiment of the invention, the rollers are rotatably connected to the rotating body, and the pivot of the rotatable connection is located at an eccentric position at the rotation center of the rotating body. This arrangement facilitates the free movement of the chair in any direction. However, the load force transmitted by the rollers will be biased to one side of the rotating body. Therefore, the first rolling element group is arranged with a large rotation radius, while the second rolling element group is arranged with a small rotation radius. Since the first rolling element group is located close to the roller pivot in the rotational radial direction, it can provide sufficient downward rotational support strength. The second rolling element group provides upward rotational support strength to the rotating body in the region near the rotation center, thereby preventing the rotating body from tilting. The double-layer rotational support structure ensures overall rotational stability.
[0039] In one embodiment, both the first rolling element group and the second rolling element group are composed of balls. The diameter of the balls in the first rolling element group is larger than that in the second rolling element group. Since the first rolling element group is mainly used to counteract the load force transmitted by the roller, this arrangement maximizes the working efficiency of the balls.
[0040] In one embodiment, the main structure of the rotating body is a bowl shape with an opening facing downwards. The outer edge of the bowl shape has a wall structure extending downwards. Hair on the ground can be blocked by the wall structure after being rolled around by the rollers, preventing hair from being rolled into the first rolling body assembly along the gap between the rotating body and the inner wall of the housing.
[0041] In one embodiment, each of the bowl-shaped sidewalls is provided with downwardly extending lugs, and the roller's pivot is mounted on the lugs. The lugs, at their ends facing an eccentric direction toward the roller's pivot, form a constricted shape that approaches each other. During chair movement, the eccentric direction of the roller's pivot is opposite to the chair's forward direction, allowing hair to... Figure 5 After the hair is caught in the roller on the left, it can be blocked by the constricted part at the position of the roller on the right, preventing the hair from being caught in the first rolling element group along the gap between the rotating body and the inner wall of the housing.
[0042] In one embodiment, the rotating body is arranged around the outer periphery of the rod and forms a sealing fit with the outer periphery of the rod, so that hair can only affect the second rolling element group and will not be drawn into the first rolling element group through the gap between the rotating body and the rod.
[0043] In one embodiment, the top of the rod is provided with a horizontally extending pin hole, and a pin passes through the pin hole. The part of the pin extending out of the pin hole can abut against the top of the housing to prevent the rod from falling out of the through hole.
[0044] In one embodiment, a downwardly extending retaining ring is provided at the top of the housing in the outer edge region of the through hole, and the top of the spring is sleeved on the outside of the retaining ring. This arrangement prevents the top of the spring from shifting, improves the stability of the elastic restoring force, and increases the friction between the top of the spring and the housing, further providing damping for the rotational motion of the sliding body.
[0045] In one embodiment, the seat is bowl-shaped with an upward opening, and the bottom of the spring is supported within the bowl-shaped cavity. This configuration increases the contact area between the bowl-shaped outer edge and the interior of the housing, thereby improving the guide support strength.
[0046] In one embodiment, the bowl-shaped bottom is provided with an upwardly extending rib in the outer edge area of the rod, and the bottom of the spring is sleeved on the rib. This arrangement prevents the bottom of the spring from shifting, improves the stability of the elastic restoring force, and increases the friction between the bottom of the spring and the housing, further providing damping for the rotational motion of the sliding body.
[0047] When using the chair according to this utility model embodiment, when pressing down on the chair by sitting on the seat or in other ways, the downward pressure compresses the spring, causing the sliding body, rotating body, and roller to retract into the housing as a whole, and the bottom of the housing contacts the ground to maintain stable support; when getting up from the seat or releasing the downward pressure, the elastic restoring force of the spring pushes the sliding body, rotating body, and roller out of the housing, making it easy to move the chair freely.
[0048] The description of the embodiments herein, including any references to directions and orientations, is for ease of description only and should not be construed as limiting the scope of protection of this utility model. The description of preferred embodiments involves combinations of features, which may exist independently or in combination; this utility model is not particularly limited to the preferred embodiments. The scope of this utility model is defined by the claims.
[0049] The above are merely preferred embodiments of the present utility model and are not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model shall be included within the protection scope of the present utility model.
Claims
1. A retractable universal roller assembly, comprising a housing and a spring, a sliding body, a rotating body, and a roller disposed within the housing, wherein the roller is rotatably connected to the bottom of the rotating body, the rotating body is rotatably connected to the bottom of the sliding body, and the spring is disposed between the sliding body and the top of the housing, characterized in that, The top of the housing has a through hole. The sliding body has a rod, a seat surrounding the rod, and a disc at the bottom of the rod. The rod matches the shape of the through hole, and the seat matches the shape of the inner wall of the housing. The retractable universal roller assembly also includes a first rolling element group and a second rolling element group. The top of the rotating body is located between the seat and the disc. The first rolling element group is rotatably supported between the seat and the top of the rotating body, and the second rolling element group is rotatably supported between the top of the rotating body and the disc. The rotation radius of the second rolling element group is smaller than that of the first rolling element group, and the rotation axis of the roller is located at an eccentric position at the rotation center of the rotating body.
2. The retractable universal roller assembly according to claim 1, characterized in that, The top of the rod is provided with a horizontally extending pin hole, in which a pin passes and at least one end of the pin extends out of the pin hole.
3. The retractable universal roller assembly according to claim 1, characterized in that, A downward-extending retaining ring is provided at the top of the housing, located at the outer edge of the through hole, and the top of the spring is sleeved on the outside of the retaining ring.
4. The retractable universal roller assembly according to claim 1, characterized in that, The seat is shaped like an upward-opening bowl, with the bottom of the spring supported within the bowl-shaped cavity.
5. The retractable universal roller assembly according to claim 4, characterized in that, The bottom of the bowl shape has an upwardly extending rib located on the outer edge of the rod, and the bottom of the spring is fitted over the rib.
6. The retractable universal roller assembly according to claim 1, characterized in that, Both the first and second rolling element groups are composed of balls, with the balls in the first rolling element group having a larger diameter than those in the second rolling element group.
7. The retractable universal roller assembly according to claim 1, characterized in that, The rotating body is arranged around the outer circumference of the rod and forms a sealed fit with the outer circumference of the rod.
8. The retractable universal roller assembly according to claim 1, characterized in that, The rotating body is bowl-shaped with its opening facing downwards.
9. The retractable universal roller assembly according to claim 8, characterized in that, The bowl-shaped structure has downwardly extending lugs on both sides. The roller's axis of rotation is located on the pair of lugs. The lugs are tapered at one end in the eccentric direction toward the roller's axis of rotation.
10. A chair, characterized in that, It includes a support leg and a retractable swivel caster assembly as described in any one of claims 1-9, wherein the housing of the retractable swivel caster assembly is disposed inside the support leg or at the bottom end of the support leg.