Front-and-back overturning hinge device of wheelchair backrest

Abstract

The utility model discloses a back-and-forth turning hinging device of a wheelchair backrest, which is characterized in that a middle hinging convex piece extends backwards from the middle of the top of a first connecting piece, and a left notch and a right notch are formed in the left side and the right side of the first connecting piece; the upper edge and the lower edge of the middle hinging convex piece extend backwards to form an upper overturning limiting convex block and a lower overturning limiting convex block which correspond to each other, and a transverse limiting groove is formed; the left side and the right side of the top of the second connecting piece extend forwards to form a left hinged protruding piece and a right hinged protruding piece respectively, a middle notch is formed, and the middle hinged protruding piece, the left hinged protruding piece and the right hinged protruding piece are jointly connected with a shaft core in a penetrating mode. The middle of the second connecting piece extends forwards to form a limiting protruding piece, and the limiting protruding piece is arranged in the middle notch. The left hinging convex piece and the right hinging convex piece are arranged at the corresponding left notch and right notch, the middle hinging convex piece is inserted into the middle notch, the limiting convex piece is inserted into the transverse limiting groove, and a moving space for the limiting convex piece is reserved in the transverse limiting groove; the product is simple in overall structure, stable in overturning and easy to assemble.

Description

Technical Field

[0001] This utility model relates to wheelchair components, specifically a front-to-back tilting hinge device for a wheelchair backrest. Background Technology

[0002] For example, Chinese Patent Publication No. CN219835770U discloses a wheelchair with a linked adjustable backrest and leg frame. The backrest frame of this product has a backrest cushion connected to it; floor casters are connected to the lower part of the seat frame; a seat cushion is connected to the top of the seat frame; the lower part of the backrest frame is hinged to the rear part of the seat frame; the upper part of the front leg frame is hinged to the front top of the seat frame; a leg frame linkage adjustment device is movably hinged between the lower section of the backrest frame and the middle part of the front leg frame; when the backrest frame is rotated counterclockwise, the backrest frame synchronously drives the leg frame linkage adjustment device to push the front leg frame forward, rotating it counterclockwise upward to raise the front leg frame and adjusting its tilt angle accordingly; when the backrest frame is rotated clockwise, the backrest frame synchronously drives the leg frame linkage adjustment device to pull the front leg frame backward, rotating it clockwise downward to lower the front leg frame and adjusting its tilt angle accordingly; the front leg frame does not need to be adjusted independently for its tilt angle, as only the backrest frame needs to be adjusted for the linkage adjustment.

[0003] The backrest of the aforementioned wheelchair is hinged to the rear of the seat frame. The lower section of the backrest and the middle of the front leg frame are movably hinged to a leg frame linkage adjustment device. When the backrest is to be flipped, the backrest is adjusted together with the leg frame linkage adjustment device in the middle of the front leg frame. Its adjustment structure is complex, with many parts, complicated assembly, and high cost.

[0004] Example 2: Chinese Patent Publication No. CN211433758U discloses an adjustable wheelchair that facilitates patient posture adjustment. This wheelchair includes a seat cushion and a backrest hinged together. An adjustment mechanism for flipping the backrest is provided at the hinge point between the seat cushion and the backrest. The adjustment mechanism includes a gear set and a transverse pin. The pin passes through the hinge point between the seat cushion and the backrest, and the end of the pin away from the hinge point is machined with helical teeth that mesh with the gear set. The gear set includes a driving wheel and a transition wheel that mesh with each other, and a transition wheel meshes between the driving wheel and the helical teeth. This technical solution adjusts the angle of the backrest and the seat cushion through a flipping mechanism.

[0005] The aforementioned wheelchair backrest tilting adjustment mechanism includes a gear set and a transverse pin. The gear set includes a meshing drive wheel and a transition wheel, and the drive wheel and the helical gear part are meshed by a transition wheel. The aforementioned adjustment structure is somewhat complex, and the gear-type backrest tilting adjustment mechanism is prone to jamming. When adjusting, the entire backrest must be tilted and adjusted, and the backrest cushion cannot be adjusted separately. Utility Model Content

[0006] The purpose of this utility model is to provide a wheelchair backrest hinge device with a reasonable structure that makes it more comfortable for people sitting in wheelchairs to lean back.

[0007] To achieve the above objectives, this utility model provides the following technical solution:

[0008] A wheelchair backrest forward and backward tilting hinge device, belonging to wheelchair components, includes a first connector, a second connector, and a shaft core. The first connector has a central hinge protrusion extending rearward from the top center. The central hinge protrusion has a left notch and a right notch on its left and right sides. The central hinge protrusion body has a first shaft through hole laterally. Corresponding upper tilting limiting protrusions and lower tilting limiting protrusions extend rearward from the upper and lower edges of the central hinge protrusion, forming a transverse limiting groove between the upper and lower tilting limiting protrusions. The second connector has a left hinge protrusion and a right hinge protrusion extending forward from the top left and right sides, respectively. A middle notch is formed between the hinge protrusion and the right hinge protrusion. The left and right hinge protrusions are laterally provided with second shaft through holes. A limiting protrusion extends forward from the middle of the second connector and is arranged in the middle notch. The left and right hinge protrusions are arranged at the corresponding left and right notches. The middle hinge protrusion is inserted into the middle notch. The limiting protrusion is inserted into the lateral limiting groove, which provides space for the limiting protrusion to move. The first and second shaft through holes are connected to a shaft core. The upper and lower flip-up limiting protrusions are flipped and limited by the limiting protrusions.

[0009] Compared with the prior art, the advantages of the wheelchair backrest forward and backward tilting adjustment device of this utility model are: when a person sits behind the wheelchair with their back against the backrest, the angle of the backrest can be adjusted by the tilting hinge device to make the person sit more comfortably, suitable for people of different heights and weights, and convenient for use in a semi-reclined sitting position. During the backward tilting process, the backward tilting is stopped when the upper tilting limit protrusion presses against the top of the limit protrusion, and the forward tilting is stopped when the lower tilting limit protrusion presses against the bottom of the limit protrusion. The overall structure is simple, the tilting is stable, the tilting adjustment is easy, the assembly is easy, and the cost is low. Attached Figure Description

[0010] Figure 1 This is a perspective view of the product of this utility model with a torsion spring;

[0011] Figure 2 This is a perspective view of the product of this utility model without a torsion spring;

[0012] Figure 3 This is a perspective view of the product of this utility model without a shaft core;

[0013] Figure 4This is a side view of the product of this utility model;

[0014] Figure 5 , Figure 6 This is an exploded view of the product of this utility model;

[0015] Figure 7 This is a perspective view of the first connecting member of the present utility model product;

[0016] Figure 8 This is a perspective view of the second connector of the present utility model product;

[0017] Figure 9 The second connecting component of this utility model is a three-dimensional view of a connecting seat, which is a single rod through hole;

[0018] Figure 10 , Figure 11 yes Figure 9 Product breakdown diagram;

[0019] Figure 12 The second connecting component of this utility model is a three-dimensional view of a connecting seat, which has a double-rod through hole;

[0020] Figure 13 , Figure 14 yes Figure 12 A breakdown diagram of the product.

[0021] First connecting piece 1, first connecting plate 1A, screw hole 1B, middle hinge protrusion 101, first shaft through hole 101A, upper flip-limiting protrusion 101B, lower flip-limiting protrusion 101C, lateral limiting groove 101D, left notch 11, right notch 12, second connecting piece 2, second connecting plate 2A, connecting seat 2B, rod through hole 2B1, left hinge protrusion 21, right hinge protrusion 22, middle notch 23, screw hole 24, second shaft through hole 25, limiting protrusion 26, shaft core 27, torsion spring 3. Detailed Implementation

[0022] like Figures 1 to 14 As shown: A front-to-back flip hinge device for a wheelchair backrest, belonging to wheelchair components, is installed between the wheelchair backrest frame and the wheelchair backrest cushion. The front-to-back flip hinge device includes a first connector 1, a second connector 2, and a shaft core 3. The main technical improvement is that the first connector 1 and the second connector 2 are integrally formed and made of aluminum or plastic.

[0023] The first connector 1 has a central hinge protrusion 101 extending rearward from the top center. The central hinge protrusion 101 has a left notch 11 and a right notch 12 on its left and right sides. The central hinge protrusion 101 has a first shaft through hole 101A in the transverse direction. The upper and lower edges of the central hinge protrusion 101 have corresponding upper flip-limiting protrusions 101B and lower flip-limiting protrusions 101C extending rearward. The upper flip-limiting protrusions 101B and lower flip-limiting protrusions 101C are ribs or strips, etc. A transverse limiting groove 101D is formed between the upper flip-limiting protrusions 101B and the lower flip-limiting protrusions 101C. The transverse limiting groove 101D gradually expands from the inside to the outside.

[0024] The top left and right sides of the second connector 2 extend forward respectively to form a left hinge protrusion 21 and a right hinge protrusion 22. The left hinge protrusion 21 and the right hinge protrusion 22 are cylindrical and arranged laterally. A middle notch 23 is formed between the left hinge protrusion 21 and the right hinge protrusion 22. The width of the middle notch 23 is basically the same as that of the middle hinge protrusion 101, which fits perfectly. The left hinge protrusion 21 and the right hinge protrusion 22 are laterally provided with a second shaft through hole 25.

[0025] The second connector 2 extends laterally forward from the middle of a limiting protrusion 26, which is arranged in the middle notch 23.

[0026] The left hinge protrusion 21 and the right hinge protrusion 22 are inserted into the corresponding left notch 11 and right notch 12, respectively. The middle hinge protrusion 101 is inserted into the middle notch 23. The limiting protrusion 26 is inserted into the transverse limiting groove 101D. The transverse limiting groove 101D has reserved space 28 for the limiting protrusion 26 to move. The moving space 28 allows the first connecting member 1 to flip back and forth relative to the second connecting member 2 through the shaft core 3. The first shaft through hole 101A and the second shaft through hole 25 are connected to the shaft core 3, which fits perfectly and is tightened with a nut to prevent it from coming off. The upper flip limiting protrusion 101B and the lower flip limiting protrusion 101C are flipped and limited by the limiting protrusion 26 to limit the maximum flip angle.

[0027] The first connecting piece 1 flips back and forth relative to the second connecting piece 2 via the shaft core 3, with a flip angle of 0 to 30 degrees. When a person sits in the wheelchair with their back against the backrest, the backrest angle can be adjusted using the flip-back hinge device to make the person sit more comfortably, suitable for people of different heights and weights, and convenient for use in a semi-reclining sitting position. During the backward flipping process, the backward flipping is stopped when the upper flipping limiting protrusion 101B presses against the top of the limiting protrusion 26, and the forward flipping is stopped when the lower flipping limiting protrusion 101C presses against the bottom of the limiting protrusion 26. The overall structure is simple, the flipping is stable, and it is easy to assemble.

[0028] Preferably, a torsion spring 3 is connected to one end or both ends of the shaft core 3 to facilitate automatic reset to the initial state; one spring leg of the torsion spring 3 is connected to the first connecting member 1 or the wheelchair backrest, and the other spring leg is connected to the second connecting member 2 or the wheelchair back frame, so that a spring is formed between the first connecting member 1 and the second connecting member 2.

[0029] Preferably, the limiting protrusion 26 is a limiting protrusion plate, a limiting protrusion strip, or a limiting protrusion rib, all of which can achieve the purpose of limiting and stopping.

[0030] Preferably, the first connector 1 is a first connecting plate 1A. The first connecting plate 1A is flat and increases the connection area to improve the stability of the connection with the wheelchair components. The first connecting plate 1A has several screw holes 1B to facilitate the fixed connection with the wheelchair backrest components.

[0031] Preferably, the second connector 2 is a second connecting plate 2A, which is flat and increases the connection area to improve the stability of the connection with the wheelchair components.

[0032] Preferably, the back of the second connecting plate 2A is provided with several horizontal grooves for easy connection with the lifting and adjusting structure of the wheelchair backrest frame to adjust the height of the wheelchair backrest.

[0033] Preferably, the second connector 2 is a connector 2B, and the connector 2B has at least one rod through hole 2B1 in the longitudinal direction for connecting to the vertical rod of the wheelchair backrest frame.

[0034] Preferably, the connecting seat 2B has two longitudinal through holes 2B1 for threading through the vertical rod of the wheelchair backrest frame.

[0035] Preferably, the first connector 1 and the second connector 2 are made of metal or plastic, both of which can achieve the purpose of connection.

[0036] Preferably, the second connector 2 has a screw hole 24 laterally opened at the top rear part for installing the through rod of the torsion spring 3, so that the torsion spring 3 has better torque.

Claims

1. A fore-and-aft tilting hinge device for a wheelchair backrest, belonging to wheelchair components, comprising a first connector, a second connector, and a shaft core, characterized in that: The first connector has a central hinge protrusion extending backward from the top center. The central hinge protrusion has a left notch and a right notch on its left and right sides. The central hinge protrusion body has a first shaft through hole opened laterally. The upper and lower edges of the central hinge protrusion have corresponding upper flip-limiting protrusions and lower flip-limiting protrusions extending backward. A transverse limiting groove is formed between the upper flip-limiting protrusion and the lower flip-limiting protrusion. The top left and right sides of the second connector have left and right hinge protrusions extending forward respectively. A middle notch is formed between the left and right hinge protrusions. The left and right hinge protrusions are laterally provided with second shaft through holes. The second connector has a limiting protrusion extending forward from the middle, and the limiting protrusion is arranged in the middle notch; The left and right hinge protrusions are arranged at the corresponding left and right notches, the middle hinge protrusion is inserted into the middle notch, and the limiting protrusion is inserted into the transverse limiting groove, which provides space for the limiting protrusion to move. The first shaft through hole and the second shaft through hole are connected to the shaft core. The upper flip limiting protrusion and the lower flip limiting protrusion are flipped and limited by the limiting protrusion.

2. The wheelchair backrest forward and backward flipping hinge device according to claim 1, characterized in that: A torsion spring is connected to one end or both ends of the shaft.

3. The wheelchair backrest forward and backward flipping hinge device according to claim 1, characterized in that: The limiting protrusion is a limiting protrusion plate, a limiting protrusion strip, or a limiting protrusion rib.

4. A wheelchair backrest forward and backward tilting hinge device according to any one of claims 1 to 3, characterized in that: The first connector is a first connecting plate, and the first connecting plate has several screw holes.

5. A wheelchair backrest forward and backward tilting hinge device according to any one of claims 1 to 3, characterized in that: The second connector is the second connecting plate.

6. The wheelchair backrest forward and backward flipping hinge device according to claim 5, characterized in that: The back of the second connecting plate has several stop grooves.

7. A wheelchair backrest forward and backward tilting hinge device according to any one of claims 1 to 3, characterized in that: The second connector is a connector seat, on which at least one rod through hole is longitudinally formed.

8. The wheelchair backrest forward and backward flipping hinge device according to claim 7, characterized in that: The connecting seat has two rod through holes longitudinally.

9. A wheelchair backrest forward and backward tilting hinge device according to any one of claims 1 to 3, characterized in that: The first connector and the second connector are made of metal or plastic, and the second connector has a screw hole laterally opened at the top rear part.

10. A wheelchair backrest forward and backward tilting hinge device according to any one of claims 1 to 3, characterized in that: The first connector is flipped back and forth relative to the second connector via a shaft core, with a flipping angle of 0 to 30 degrees.

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