Biasing drive wheel assembly adaptable to a wheelchair

Abstract

This invention provides a biased drive wheel assembly that can be attached to a wheelchair. Its main features include a central base, symmetrical support brackets, a grounding wheel assembly, and operating components. The left and right support brackets connect the inner and outer arms via elbow joints, and, in conjunction with the sliding seats of the central base, achieve support and folding modes. When supported, the outer arms are laterally extended to assemble the wheelchair; when folded, they are bent at elbows. The grounding wheel assembly is pivotally connected to the central base via an oblique swing frame, and its grounding performance is ensured by a spring-loaded telescopic member that normally presses down on the drive wheels. A swing angle limiting component is also provided to prevent excessive swinging. The user switches modes via the operating components. When switched to the pressing mode, the positioning rod engages and locks into the locking seat; the positioning rod also has a lateral abutment edge, effectively eliminating gaps and improving overall structural stability.

Claims

1. A biased drive wheel assembly that can be attached to a wheelchair, the biased drive wheel assembly comprising: a central seat, extending vertically and including an upper end, a lower end, and a seat section between the upper end and the lower end, wherein the upper end is slidably fitted with a slide seat capable of a limited travel of vertical displacement, the lower end extending laterally to form two lateral pivot portions, and the slide seat having an operating side; an elbow joint having a second pivot portion for pivotally connecting to the corresponding lateral pivot portion of the central seat; Two support frames are symmetrically arranged on both sides of the central seat. Each support frame includes an inner arm and an outer arm, which are connected to each other by an elbow joint. The inner end of the inner arm is pivotally connected to the slide of the central seat via a first pivot, allowing it to be raised and lowered. The outer end of the outer arm is pivotally connected to a wheelchair assembly component. Thus, with both the first and second pivots being pivot points and the first pivot being raised and lowered, the inner and outer arms can move at elbow joints. This results in two support frames having a supporting mode and a folding mode. In the supporting mode, the inner arm is upright and the outer arm is relatively straight and laterally extended. Conversely, in the folding mode, the inner arm is oblique and the outer arm is relatively upright and bent at the elbow. Two locking and positioning seats are provided on the front side of the inner arm of each of the tension brackets, and each locking and positioning seat forms a locking groove; a grounding wheel assembly includes an inclined swing frame and a drive wheel, wherein the drive wheel is spun at the lower end of the inclined swing frame, and the upper end of the inclined swing frame is pivotally connected to the lower end of the middle seat body by a third pivot part; an operating component includes a lever part and a set of connecting seats connected to the lever part, wherein the set of connecting seats includes an upper pivot part and a lower pivot part, the upper pivot part is pivotally connected to the operating side of the slide, wherein the lever part can be levered with the upper pivot part as a fulcrum and has an up lever mode and a down lever mode. In the up lever mode, the lower pivot part is driven away from the operating side, and in the down lever mode, the lower pivot part is driven closer to the operating side; A spring-loaded telescopic member includes an upper connecting end and a lower connecting end, wherein the upper connecting end is connected to the lower pivot portion of the operating component, and the lower connecting end is connected to the inclined swing frame of the grounding wheel assembly. The spring-loaded telescopic member is used to elastically press down on the inclined swing frame under normal conditions. A positioning rod includes two positioning sections, which are disposed between the operating component and the spring-loaded telescopic member, or on either of their structures. When the two support brackets are in the supporting mode and the lever portion of the operating component is in the pressing mode, the two positioning sections are correspondingly embedded in the two locking positioning seats. Each positioning segment of the positioning rod is further provided with two lateral abutment edges to abut against the two sides of the corresponding locking positioning seat to eliminate lateral fitting gaps.

2. The bias drive wheel set that can be attached to a wheelchair as described in claim 1, wherein the back side of the slide seat that is slidably fitted at the upper end of the middle seat body and the back side of the elbow joint between the inner and outer arms are further connected to each other through two oblique connecting arms, so that when the two tension supports switch between the support mode and the folding mode, they can form an auxiliary linkage effect on the slide seat.

3. The bias drive wheel set that can be attached to a wheelchair as described in claim 1, wherein the slide seat that is slidably fitted on the upper end of the middle seat body is formed with an elongated guide hole, so that the upper end of the middle seat body is provided with a lateral limiting bolt to limit the upper and lower displacement of the elongated guide hole to a fixed position, thereby achieving the purpose of limiting the lifting displacement stroke of the slide seat.

4. The bias drive wheel assembly that can be attached to a wheelchair as described in claim 1, wherein an actuation axis (X) is defined from the upper pivot of the assembly to the lower connecting end of the elastic telescopic member, an upper actuation distance (L1) is defined from the upper pivot to the upper connecting end of the elastic telescopic member, and a lower actuation distance (L2) is defined by the maximum free length from the upper connecting end to the lower connecting end of the elastic telescopic member, wherein... The sum of the upper segment actuation distance (L1) and the lower segment actuation distance (L2) must be greater than the actuation axis (X).

5. The bias drive wheel set that can be attached to a wheelchair as described in claim 4, wherein a swing angle limiting member is provided at the position corresponding to the ground wheel set on the center seat to limit the maximum downward swing of the inclined swing frame of the ground wheel set.

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