Automatic brake of manual wheelchair

Abstract

The invention relates to an automatic brake for a manual wheelchair. The device is specially designed for tires made of particularly hard PU materials, and is not used for rubber tires, pneumatic tires and soft PU tires. The core technology of the product is a specially researched and developed metal brake wheel. Only the brake wheel which is made of a special metal material and has a special structure and is tested through multiple tests has a braking effect. The main structural components comprise a supporting piece capable of being connected with the manual wheelchair, a first shaft connected with the other end of the supporting piece and provided with three notches in the periphery, and a pivotable first handle with a pawl. Wherein a first handle on the first shaft can occupy three positions defined by the three recesses, a pin connected to the first handle and disposed parallel to the first shaft, an eccentric ring having a recess, the pin and being engageable with the outer circumference of the wheelchair of the pulley, an extension spring connecting the inner circumference of the eccentric ring and the pin, and a stop element protruding from the first shaft, the stop element being able to abut against the inner circumference of the eccentric ring.

Description

Technical Field

[0001] The invention relates to an automatic brake for a manual wheelchair specially made of hard PU material. Background Art

[0002] At present, the tires corresponding to the brake part of most manual wheelchairs in China are particularly hard PU tires. This type of tire is cheap, maintenance-free, and has many advantages. At present, the domestic handle brake is used to prevent the rotation of the wheel, thereby stabilizing the position of the wheel in a specific position. For example, the brake of most manual wheelchairs in China is to control a long iron sheet extending out through the operating handle, and the iron sheet is stuck into the rubber tire for braking. This braking method requires a certain amount of force to pull the operating handle, which is not a very friendly operation for the elderly. The characteristic is that it is cheap. Especially for manual wheelchairs, this brake cannot achieve wheel braking in only one direction. That is why we developed a new type of brake that allows the wheel to rotate in one direction and prevents it from rotating in the opposite direction. This brake is practical and effective when manual wheelchairs and other products go uphill. Enhanced product safety performance. Prevent wheelchairs from falling back. For the elderly and babies, safety is the most important thing. And because of the combined power-assisting devices such as springs, our handle operation is very easy, which is a very friendly operation for the elderly. Therefore, our product invention has important and special significance for a large group of special humans.

[0003] The present invention relates to a brake formed by a ratchet. The special feature is the material of the brake wheel. Ordinary rubber rings cannot brake because the tire of hard PU material is very slippery. After many experiments, we have developed a metal brake ring with special metal material and special appearance structure, which perfectly solves this problem. However, the brake with this metal material and special structure can only be used for hard PU material tires. It has poor braking effect on other rubber rings, pneumatic tires, and soft PU material tires. In order to explain the problem more clearly, the application environment of the brake product is given as an example. This article uses the brake on a manual wheelchair to illustrate the problem. The brake is fixed on the circular tube of the manual wheelchair (most of the domestic manual wheelchairs have a diameter of 22.5 mm), and includes an axle, a brake wheel that can rotate on the axle and is provided with internal teeth, a pin that can be movably arranged through the axle, and a lever mechanism with a first handle, and the first handle enables the brake wheel to engage with the outer circumference of the rubber tire of the manual wheelchair. The inner teeth and pin of the brake wheel are designed in such a way that when the manual wheelchair rotates in one direction, the pin slides on the inner teeth, and when the manual wheelchair rotates in the opposite direction, the pin locks the brake wheel. Therefore, the manual wheelchair can travel upwards while being prevented from moving backwards.

[0004] The brake can adopt three positions: a first position, in which the rotation of the wheels of the manual wheelchair is enabled, a second position, in which the rotation of the wheels of the manual wheelchair is disabled, and a third position, in which the rotation of the wheels of the manual wheelchair is disabled only in one direction. The brake comprises a crank mechanism with a handle part for shifting, braked to one of the three positions mentioned above, a shaft and a brake element, pivotally mounted on the shaft and selectively engaging with the peripheral surface of the wheel of the manual wheelchair. The brake element is designed in such a way that the radius of the brake surface increases at the periphery. The third position of the brake enables the wheel of the manual wheelchair to rotate in one direction, while when the wheel rotates in the opposite direction, the brake element engages with the manual wheelchair wheel, thereby preventing its rotation. Summary of the invention

[0005] The technical problem is to conceive an automatic brake for a manual wheelchair, which has a simple and reliable structure and can selectively achieve one-way braking of the wheels of a manual wheelchair, a baby stroller, etc. when the manual wheelchair moves forward or backward.

[0006] Solutions to technical problems

[0007] The technical problem is solved by a brake for a manual wheelchair, the brake comprising:

[0008] 1. A support member, one end of which can be connected to the circular pipe member of the frame of the manual wheelchair.

[0009] 2. A first shaft connected to the other end of the support member.

[0010] 3. A first handle with a detent, the first handle being pivotably arranged on the first shaft, wherein the first handle can occupy three positions on the first shaft defined by the three notches.

[0011] 4. A pin, one end of which is firmly connected to the first handle and is arranged parallel to the first axis at a radial distance from the pin.

[0012] 5. An eccentric ring with a closed bottom, in which is formed at least an arcuate recess concentric with the first shaft, through which the pin protrudes, wherein the eccentric ring is pivotally mounted on the first wheel shaft and can engage with the outer periphery of the pulley.

[0013] 6. A tension spring connecting the inner periphery of the eccentric ring and the pin.

[0014] 7. A stop element protruding from the first shaft, the stop element being abuttable against the inner periphery of the eccentric ring, thereby preventing the eccentric ring from pivoting in one direction about the first axis.

[0015] Based on the user's selection, the first handle with the detent can assume three positions: a first end position, a second end position and an intermediate position between the two end positions.

[0016] In the middle position, the eccentric ring is away from the outer periphery of the roller and the roller can rotate freely. In this position, the first handle with a pawl, the tension spring and the stop element are aligned. The tension spring forces the eccentric ring into the center position.

[0017] The movement of the first handle from the middle position to the first end position causes the movement of the eccentric ring so that the outer periphery of the eccentric ring contacts the outer periphery of the roller. When the roller rotates in one direction, it overcomes the force of the tension spring to push the eccentric ring away from the roller, thereby enabling the roller to rotate. When the roller rotates in the other direction, it pushes the eccentric ring onto the roller to produce a blocking effect, thereby preventing the roller from rotating. The stop element rests on the inner periphery of the eccentric ring and prevents further rotation of the eccentric ring around the first axis and thus prevents the eccentric ring from approaching too close to the wheel of the manual wheelchair. When the first handle is moved from the middle position to the second end position, the situation is similar to the above situation, except that here a one-way braking in the opposite direction of the manual wheelchair wheel rotation is achieved.

[0018] Compared with known brakes, the advantage of the manual wheelchair automatic brake is that it can achieve unidirectional braking of the wheels of manual wheelchairs and other products in forward or backward movement. Another advantage is the simple structure of the brake and its reliable operation, and the operation is very flexible and light.

[0019] Figure 1 :Brake Actual Picture

[0020] Figure 2 : Brake cross section

[0021] Figure 3 : Brake side view

[0022] Figure 4 : Cross section of brake with crank mechanism

[0023] Figure 5 : Side view of brake with crank mechanism

[0024] Figure 6a : Brake in one-way braking position

[0025] Figure 6b : Brake in released position

[0026] Figure 7a : Brake with crank mechanism in bidirectional braking position

[0027] Figure 7b : Brake with crank mechanism in one-way braking position

[0028] Figure 8 : Brake with concentric eccentric ring

[0029] Fig. 9 : Brake with eccentric ring and linked brake pad

[0030] Fig.10 : Brake with two permanent magnets DETAILED DESCRIPTION

[0031] The technical problem solves the manual wheelchair braking problem by an automatic brake for a manual wheelchair, the brake comprising:

[0032] A support 2, whose first end can be connected to a frame circular tube 32 of a manual wheelchair. A first shaft 3, which is connected to the other end of the support. A first handle 4 with a pawl 5, which is pivotally arranged on the first shaft 3, and wherein the first handle 4 can be in three positions on the first shaft 3, which are defined by three notches 3a. A pin 6, one end of which is firmly connected to the first handle 4 and is arranged parallel to the first shaft 3 at a radial distance from the first shaft 3.

[0033] An eccentric ring 7 having a closed bottom 7a, in which an arc-shaped recess 7b at least concentric with the first axis is formed, through which a pin 6 protrudes, wherein the eccentric ring 7 is pivotally mounted on the first axis 3 and engages with the outer periphery of the roller 30. A tension spring 8 connecting the inner periphery of the eccentric ring 7 and the pin 6, and a stopper element 9 protruding from the first axis 3, which can abut against the inner periphery of the eccentric ring 7 to prevent the eccentric ring 7 from rotating around the first axis 3 in one direction.

[0034] Based on the user's selection, the first handle 4 with the pawl 5 can adopt three positions corresponding to the three recesses 3a: a first end position, a second end position and an intermediate position between the two end positions.

[0035] In the middle position, the eccentric ring is away from the outer periphery 30 of the roller and the roller can rotate freely. In this position, the first handle 4 is aligned with the pawl 5, the tension spring 8 and the stop element 9. The tension spring 8 forces the eccentric ring 7 into the center position.

[0036] The pawl 5 of the first handle 4 may be formed by a pressure spring 5 a and a ball 5 b which may engage with the three notches 3 a on the first shaft 3 .

[0037] The movement of the first handle 4 from the middle position to the first end position causes the movement of the eccentric ring 7 so that the outer periphery of the eccentric ring contacts the outer periphery of the roller. When the roller 30 rotates in one direction, it overcomes the force of the tension spring 8 to push the eccentric ring 7 away from the roller 30, thereby enabling the roller to rotate. When the manual wheelchair wheel rotates in the other direction, due to the blocking effect, it pushes the eccentric ring 7 against the pulley 30, thereby prohibiting the rotation of the manual wheelchair wheel. The stop element 9 rests on the inner periphery of the eccentric ring 7 and prevents the eccentric ring from further rotating around the first axis 3 and thus prevents the eccentric ring 7 from resting too much on the wheel of the manual wheelchair.

[0038] When the first handle is moved from the intermediate position to the second end position, the situation is similar to the above situation, except that here a one-way braking in the opposite direction of the manual wheelchair wheel rotation is achieved.

[0039] The outer periphery of the eccentric ring 7 may be coupled 7c, which improves the braking efficiency in dry and wet conditions. The eccentric ring 7 may also be provided on its outer periphery by a brake pad 10. The brake pad 10 may be formed in a corrugated shape from the outside. The material of the brake pad 10 may be glass fiber reinforced neoprene.

[0040] The support 2 can be securely connected to the frame circular tube of the manual wheelchair. This roller brake is applicable to be arranged on the manual wheelchair.

[0041] In another operating case, the support 2 can be articulated with the frame 32 of a manual wheelchair. In this case, the middle part of the support 2 is articulated with the crank mechanism 12 via the second handle 11, which in turn can be articulated with the frame 32 of the manual wheelchair. If the second handle is moved, the eccentric ring 7 can additionally occupy a position of bidirectional braking of the roller 30 when the first handle 4 is in the middle position.

[0042] The roller brake further comprises a cover 15, and the eccentric ring 7 is covered by the cover 15. The roller brake further comprises a first permanent magnet 33 and a second permanent magnet 34, wherein, when the first handle 4 is in its intermediate position, the first permanent magnet 33 is arranged on the first handle 4 facing the eccentric ring 7, and the second permanent magnet 34 is arranged on the eccentric ring 7 opposite to the first permanent magnet 34. The first permanent magnet 33 and the second permanent magnet 34 must be oriented in a mutually attractive manner. When the manual wheelchair moves on an uneven ground (for example, a sandy ground), the role of the permanent magnets is to prevent the eccentric ring 7 from oscillating around the first axis 3; the eccentric ring 7, more precisely its brake pad 10, is thereby prevented from engaging with the tire periphery of the manual wheelchair.

Claims

1. An automatic brake for a manual wheelchair specially used for PU hard tires, comprising: (1) A support member (2) The first end of the support member can be connected to the circular tube member (32) of the manual wheelchair. A first shaft (3) connected to the other end of the support member, a first handle (4) with a pawl (5), and a pin (6) of the handle (4), one end of which is firmly connected to the first handle (4) and is arranged parallel to the first shaft (3) at a radial distance from the pin. an eccentric ring (7) having a closed bottom (7a), in which an arcuate recess (7b) is formed which is at least concentric with the first axis, through which the pin (6) protrudes, wherein the eccentric ring (7) is pivotally mounted on the first axle (3) and is engageable with the outer periphery of a tram wheel (30), a tension spring (8) connecting the inner circumference of the eccentric ring (7) and the pin (6), and a stop element (9) protruding from the first axis (3), the stop element being able to rest on the inner circumference of the eccentric ring (7) to prevent the eccentric ring (7) from rotating in one direction around the first axis (3).

2. The brake according to claim 1, characterized in that Based on the user's selection, the first handle (4) with the pawl (5) can be positioned to three positions corresponding to the three notches (3a): a first end position, a second end position and an intermediate position between the two end positions.

3. Brake according to any one of the preceding claims, characterized in that When the first handle (4) is aligned with the pawl (5), the tension spring (8) and the stop element (9), (4) is in a neutral position.

4. Brake according to any one of the preceding claims, characterized in that The pawl (5) of the first handle (4) is formed by a pressure spring (5a) and a ball (5b) which is capable of engaging with the three notches (3a) on the first shaft (3).

5. Brake according to any one of the preceding claims, characterized in that The eccentric ring (7) is connected to (7c) on its outer circumference. Brake according to any of the preceding claims, characterized in that the eccentric ring (7) is provided with a brake pad (10).

6. The brake according to claim 1, characterized in that: The brake pad (10) is corrugated from the outside. The brake according to claim 1, wherein the brake pad (10) is formed of a special metal material and a special shape.

7. Brake according to any one of the preceding claims, characterized in that The support member (2) can be securely connected to the frame of the trolley.

8. The brake according to claim 1, characterized in that Specially developed metal materials and special appearance structure result in an outer ring brake wheel with a very special braking effect specifically designed for hard PU tires.

9. The brake according to claim 1, further comprising a crank mechanism (12) and a second handle (11), wherein: The middle part of the retainer (2) is hinged to a second handle (11) that can be hinged to the frame (32) of the trolley through the crank mechanism (12), so that when the first handle (4) is in the middle position, the eccentric ring (7) can enter the bidirectional braking position of the trolley wheel (30) by moving the second handle.

10. Brake according to any one of the preceding claims, characterized in that It also includes a first permanent magnet (33) and a second permanent magnet (34), wherein the first permanent magnet is arranged on the first handle (4) facing the eccentric ring (7), and the second permanent magnet, when the first handle (4) is in its middle position, the eccentric ring (7) is arranged opposite to the first permanent magnet (33), wherein the first (33) and the second (34) permanent magnets are oriented in a mutually attractive manner.

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