Backrest rotation mechanism

Abstract

This invention provides a backrest rotation mechanism that allows for rotational adjustment of the backrest's support level with a simple pressing motion, and also reduces the overall packaging volume by lowering it for storage. [Solution] The backrest rotation mechanism includes a rotation mechanism 3 provided between the backrest 1 and the chair back tube 2. The rotation mechanism has a mounting base 31, a main base 32, a shaft 33, a pressing unit 34, and a cover 35. The mounting base is coupled to one end of the back of the backrest. The mounting base has a protrusion 311 in the center and a rotation groove 312 formed around it. A rotation shaft hole 313 is formed in the center of the protrusion. At least two fitting holes 314 are formed around the rotation shaft hole. An elastic member 315 and a locking member 316 are sequentially inserted into each fitting hole. The main base is assembled and coupled to the chair back tube in correspondence.

Description

[Technical Field]

[0001] The present invention relates to a chair backrest adjustment technology, and in particular to a backrest rotation mechanism. [Background Art]

[0002] Conventionally, in chairs for people to sit on, in order to improve sitting comfort, manufacturers adjust the position of related components to perform appropriate direction adjustment according to the body shape of each user (for example, the height of the chair, the height of armrests or the displacement thereof in the anteroposterior direction and inward-outward direction, the inclination of the backrest or the displacement thereof in the anteroposterior direction), so that components can be adjusted flexibly in a timely manner when the user uses the chair.

[0003] Generally, the height of a chair backrest needs to be adjusted based on each user's height, "usage conditions" and "body support requirements", so as to reliably and closely support the lumbar spine and back, and prevent the top end of the chair backrest from pressing against the shoulders. When adjusted appropriately, the pressure on the back can be effectively dispersed, and stiffness in the shoulders and neck, low back pain, back pain and other conditions can be prevented. Many adjustment structures or devices have already been commercially available, such as the chair backrest height adjustment structure disclosed in Patent Document 1, and the chair backrest height adjustment device for office chairs disclosed in Patent Document 2. However, although the above-mentioned structures can adjust the height of the chair (backrest), they have complicated structures and relatively high costs. In addition, these chairs cannot be adjusted to a lower position to effectively reduce their volume. As a result, when the product is transported, the packaging volume is large and takes up much space, which easily leads to high transportation costs.

[0004] Therefore, based on the supreme concept of perfecting the product, with the help of years of manufacturing and design experience and knowledge in the related field, the inventor of the present invention devised the present invention through multi-faceted ingenuity and experiments. [Prior Art Documents] [Patent Documents]

[0005] [Patent Document 1] Taiwan Utility Model Registration No. M564967 (Publication) [Patent Document 2] Taiwan Utility Model Registration No. M408995 (Publication) [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] The main objective of this invention is to provide a backrest rotation mechanism that allows for rotational adjustment of the backrest's support level with a simple pressing motion, and reduces the overall packaging volume by adjusting it to a lower position for storage. [Means for solving the problem]

[0007] To solve the above problems, according to the first embodiment of the present invention, a backrest rotation mechanism is provided, which is provided between the backrest and the chair back tube, wherein the rotation mechanism comprises a mounting seat, a main base, a shaft, a pressing unit and a cover, the mounting seat is coupled to one end of the back of the backrest, the mounting seat has a protrusion in the center and a rotating groove formed around it, a rotating shaft hole is formed in the center of the protrusion, at least two fitting holes are formed around the rotating shaft hole, an elastic member and a locking member are sequentially inserted into each fitting hole, the main base is assembled and coupled in correspondence to the chair back tube, the main base has an internal recess space in the center that accommodates the corresponding protrusion and an annular edge formed around it that can be fitted into the rotating groove, and the main A backrest rotation mechanism is provided, characterized in that a fixed shaft hole is formed in the inbase at a position corresponding to the rotation shaft hole, a perforation is formed at a position corresponding to at least two of the fitting holes, the shaft is inserted corresponding to the fixed shaft hole of the main base and the rotation shaft hole of the mounting seat, the backrest is rotatably mounted on the chair back tube, the pressing unit has a first stepped portion and a second stepped portion of different outer diameters and a convex ring provided between the first stepped portion and the second stepped portion, the first stepped portion is fitted into the perforation, the cover has a grooved hole for accommodating the convex ring of the pressing unit, the grooved hole has a through hole for inserting the second stepped portion of the pressing unit, and when the cover is screwed onto the main base in correspondence, it covers and positions the pressing unit.

[0008] Preferably, shaft sleeves are provided in the fixed shaft hole of the main base and the rotating shaft hole of the mounting seat, and the shaft is inserted through and fixed into the shaft sleeve.

[0009] Preferably, the backrest includes a first end and a second end having different curvatures or different shapes. [Effects of the Invention]

[0010] The backrest rotation mechanism according to this invention allows for rotational adjustment of the backrest's support level with a simple pressing motion, and by adjusting it to a lower position for storage, the overall packaging volume can be reduced. [Brief explanation of the drawing]

[0011] [Figure 1] This is an exploded perspective view showing a backrest rotation mechanism according to one embodiment of the present invention. [Figure 2] This is an assembled perspective view showing a backrest rotation mechanism according to one embodiment of the present invention. [Figure 3] This is a cross-sectional view (1) showing a backrest rotation mechanism according to one embodiment of the present invention. [Figure 4] This is a cross-sectional view (2) showing a backrest rotation mechanism according to one embodiment of the present invention. [Figure 5] This is a cross-sectional view (3) showing a backrest rotation mechanism according to one embodiment of the present invention. [Modes for carrying out the invention]

[0012] To more fully and clearly disclose the technical details, objectives, and effects achieved in this invention, they will be described in detail below. Please also refer to the accompanying drawings and reference numerals.

[0013] First, refer to Figures 1 and 2. Figure 1 is an exploded perspective view showing a backrest rotation mechanism according to one embodiment of the present invention. Figure 2 is an assembled perspective view showing a backrest rotation mechanism according to one embodiment of the present invention.

[0014] As shown in Figures 1 and 2, the backrest rotation mechanism according to one embodiment of the present invention includes a rotation mechanism 3 provided between the backrest 1 and the chair back tube 2.

[0015] As shown in Figures 1 and 2, the rotation mechanism 3 included in one embodiment of the present invention comprises a mounting base 31, a main base 32, a shaft 33, a pressing unit 34, and a cover 35.

[0016] Said mounting seat 31 is coupled to one end of the back portion of a backrest 1. Said mounting seat 31 comprises a protruding portion 311 provided at a central portion thereof and a rotation groove path 312 formed on the periphery thereof. A rotation shaft hole 313 is formed in the central portion of said protruding portion 311. At least two fitting holes 314 are formed around said rotation shaft hole 313. An elastic member 315 and a locking member 316 are sequentially inserted into each of said fitting holes 314.

[0017] Said main base 32 is correspondingly assembled and coupled onto a chair back tube 2. Said main base 32 is provided with an inwardly recessed space 321 at a central portion thereof for correspondingly accommodating said protruding portion 311, an annular edge 322 capable of being fitted into said rotation groove path 312 is formed on the periphery thereof, and a fixed shaft hole 323 is formed at a position corresponding to the rotation shaft hole 313 of said main base 32. A through hole 324 is formed at a position corresponding to at least two of said fitting holes 314.

[0018] Said shaft rod 33 is inserted corresponding to the fixed shaft hole 323 of the main base 32 and the rotation shaft hole 313 of the mounting seat 31, so that said backrest 1 is rotatably mounted onto the chair back tube 2.

[0019] A pressing unit 34 comprises a first step portion 341 and a second step portion 342 having different outer diameters, and a protruding ring 343 provided between the first step portion 341 and the second step portion 342. Said first step portion 341 is fitted into said through hole 324.

[0020] A cover 35 has a slot hole 351 for accommodating said protruding ring 343 of said pressing unit 34. Said slot hole 351 has a through hole 352 for allowing the second step portion 342 of said pressing unit 34 to pass through. When said cover 35 is correspondingly screwed onto said main base 32, it covers and positions said pressing unit 34.

[0021] Reference is made to FIGS. 1 to 5. As shown in Figures 1 to 5, the backrest rotation mechanism according to the present invention is installed on any chair that requires a backrest 1 to be attached when actually used. The backrest 1 described above includes a first end 11 and a second end 12 having different curvatures or different shapes. As shown in Figures 1 to 5, the mounting base 31 is located on the back of the first end 11 of the backrest 1 described above. Furthermore, the connection between the main base 32 and the chair back tube 2 described above can be made using various methods. Figures 1 to 5 show the main base 32 connected to the chair back tube 2 via a connecting seat A (this technology is currently under separate patent application), but since this is not a technical feature of the present invention, a detailed explanation will be omitted. However, when the main base 32 and the mounting seat 31 of the backrest 1 are assembled and positioned via the shaft 33, a shaft sleeve 331 is provided in the fixed shaft hole 323 of the main base 32 and the rotating shaft hole 313 of the mounting seat 31, and the shaft 33 is inserted through the shaft sleeve 331 and fixed in place.

[0022] When assembled at a low position, the locking member 316 in the fitting hole 314 of the mounting seat 31 comes into contact with the end face of the recessed space 321 of the main base 32, causing the locking member 316 to compress the elastic member 315 and shrink into one of the fitting holes 314. Furthermore, the fitting hole 314 on the other side of the mounting seat 31 and the perforation 324 in the main base 32 correspond to each other, and when the locking member 316 is pressed by the elastic force of the elastic member 315 and fitted into the perforation 324 in the main base 32, the pressing unit 34 is pressed and retracted, and the pressing unit 34 is positioned and restrained within the groove 351 of the cover 35 via the convex ring 343. At this time, the locking member 316, which is fitted into and locked in the hole 324 of the main base 32 described above, restrains the position of the backrest 1 described above and prevents the backrest from rotating (see Figure 3).

[0023] Refer to Figure 4. As shown in Figure 4, when adjusting the backrest 1 described above, first, the pressing unit 34 described above is pressed down to release the lock, and the locking member 316 described above is pressed against the first stepped portion 341 of the pressing unit 34 described above. When the locking member 316 compresses the elastic member 315 described above and disengages it from the perforation 324 described above, the lock is immediately released. Next, by rotating the backrest 1 as described above, the rotation groove 312 of the mounting base 31 and the annular edge 322 of the main base 32 are rotated relative to each other, and the second end 12 of the backrest 1 is rotated upward, so that the locking member 316 in the fitting hole 314 of the mounting base 31 is rotated until it corresponds to the hole 324 of the main base 32. The aforementioned perforation 324 is pressed by the elastic force of the aforementioned elastic member 315, and when the aforementioned locking member 316 is fitted into contact with it, the locking member 316 fitted into the perforation 324 of the main base 32 locks the aforementioned backrest 1 in position, and completes the rotation adjustment of the aforementioned backrest 1 and locks it (see Figure 5). With this configuration, the user can adjust the rotation of the first end 11 and the second end 12 of the backrest 1 by designing them with different curvatures or different shapes, and by supporting the user's back with the backrest, a different sense of support can be obtained, thereby improving seating comfort.

[0024] It is worth noting that this invention allows the user to rotate and adjust the height of the backrest 1 based on their height or desired comfort level. Furthermore, by rotating the backrest 1 to a lower position, the volume of the packaging material is reduced, increasing the number of items that can be loaded into a container for transport. This effectively saves space, reduces transportation costs, and provides a more convenient transport experience.

[0025] The embodiments or drawings described above do not limit the form, structure, or method of use of the product of this invention, and appropriate modifications or alterations by persons with ordinary skill in the art should be considered to be included within the scope of the utility model registration claims of this invention.

[0026] As can be seen from the above-described structural composition and usage of the present invention, the present invention has the following advantages (1) to (4) compared to conventional structures.

[0027] (1) The design allows the user to adjust the height of the backrest by pressing and rotating, enabling multi-stage rotation adjustment according to each user's height and the comfortable backrest support height desired by the user. (2) As described above, the support height of the backrest can be adjusted by rotation, and the design of the first and second ends of the backrest with different curvatures or different shapes allows for different support sensations when the back is supported, thereby improving seating comfort. (3) The height of the backrest can be adjusted by rotating it with a simple pressing motion, making it highly convenient to use and operate. (4) By adjusting the backrest to a lower position, the overall packaging volume of the chair can be reduced, increasing the amount of product that can be loaded and transported, and effectively saving on transportation costs.

[0028] In summary, the embodiments of this invention can reliably achieve the expected effects of use, and the specific structure disclosed is not only unique to this type of product but has also not been publicly disclosed prior to filing, thus fully satisfying the provisions and requirements of the Utility Model Law. Therefore, in accordance with the law, we hereby file this application for registration of a utility model. [Explanation of Symbols]

[0029] 1 Backrest 2 Chair back tube 3 Rotation mechanism 11 First end 12 Second end 31 Mounting base 32 Main Base 33 Axle rod 34 Pressing Unit 35 Cover 311 Convex part 312 Rotary groove road 313 Rotating shaft hole 314 Fitting hole 315 Elastic member 316 Locking member 321 Inner concave space 322 Annular edge 323 Fixed shaft hole 324 Perforation 331 Axis Sleeve 341 First section 342 Second section 343 Convex ring 351 Groove 352 Through hole A connection seat

Claims

1. A backrest rotation mechanism, which includes a rotation mechanism installed between the backrest and the chair back tube, The rotating mechanism comprises a mounting base, a main base, a shaft, a pressing unit, and a cover. The mounting base is connected to one end of the back of the backrest, and the mounting base has a protrusion in the center and a rotating groove formed around it, a rotating shaft hole is formed in the center of the protrusion, and at least two fitting holes are formed around the rotating shaft hole, and an elastic member and a locking member are sequentially inserted into each of the fitting holes. The main base is assembled and joined to the chair back tube, and the main base has a central recessed space that accommodates the corresponding protrusion, and an annular edge formed around it that can be fitted into the rotating groove, and a fixed shaft hole is formed in the main base at a position corresponding to the rotating shaft hole, and perforations are formed at positions corresponding to at least two of the fitting holes, The shaft is inserted in correspondence with the fixed shaft hole of the main base and the rotating shaft hole of the mounting seat, and the backrest is rotatably mounted on the chair back tube. The pressing unit has a first stepped portion and a second stepped portion of different outer diameters, and a convex ring provided between the first stepped portion and the second stepped portion, the first stepped portion being fitted into the hole, A backrest rotation mechanism characterized in that the cover has a groove for accommodating the convex ring of the pressing unit, the groove has a through hole for inserting the second stepped portion of the pressing unit, and when the cover is screwed onto the main base in correspondence, it covers and positions the pressing unit.

2. A shaft sleeve is provided in the fixed shaft hole of the main base and the rotating shaft hole of the mounting seat. The backrest rotation mechanism according to claim 1, characterized in that the shaft is inserted through and fixed in the shaft sleeve.

3. The backrest rotation mechanism according to claim 1 or 2, characterized in that the backrest includes a first end and a second end having different curvatures or different shapes.

Images