Electric lifting mechanism for an electric vehicle head of a wheelchair with a safety device

Description

Technical field

[0001] The invention relates to an electric lifting mechanism with a safety device for an electric head of a wheelchair.Background technology

[0002] A patent application US2018140486A1 discloses a wheelchair electric mobility attachment with a lifting mechanism wherein the lifting mechanism comprises a linear actuator, a lifting arm, and a lifting arm connector. The linear actuator is connected to the body of the wheelchair electric mobility attachment and to the lifting arm. The lifting arm is connected to the lifting arm connector fixed rotatably to the body of the wheelchair electric mobility attachment.

[0003] The existing clamping mechanisms of the connecting part of an electric head of a wheelchair and a wheelchair mostly use a bolt connecting clamping block to fix the electric wheelchair head and wheelchair. For some of clamping mechanisms using an electric push rod as the driving part, their size is large in order to increase the swing angle.

[0004] The object of the present invention is to provide a reduced-size electric lifting mechanism with increased swing angle of its swing arm.Summary of the invention

[0005] The above object of the invention is achieved by the technical solution in a form of an electric lifting mechanism for an electric head of a wheelchair comprising an electric push rod, a first connecting rod, and a swing arm. Said mechanism further comprises a connecting block, and a second connecting rod. An upper end of the electric push rod is hinged on the upper end of the connecting block, the pushing end part of the electric push rod is respectively hinged with the upper end of the first connecting rod and the second connecting rod, the lower end of the first connecting rod is hinged with the middle part of the connecting block, the lower end of the second connecting rod is hinged with the upper part of the swing arm, the upper end of the swing arm is hinged in the middle of the connecting block, and the hinge point of the swing arm and the connecting block is located above the hinge point of the upper part of the swing arm and the lower end of the second connecting rod. Said mechanism further comprises a safety device.

[0006] The safety device comprises at least one locking nut and a locking bolt wherein the middle part of the locking bolt is transversely disposed and fixed at the lower end of the connecting block, the two ends of the locking bolt protrude out of the connecting block, at least one of the two protruding ends of the locking bolt is connected to the locking nut and the bottom surface of the locking nut have circular chamfers. The lower end of the swing arm has a section of the inclined surface and the chamfer on the bottom surface of the locking nut abuts against the inclined surface of the lower end of the swing arm to lock the swing arm.

[0007] Preferably, the safety device comprises two locking nuts and the two protruding ends of the locking bolt are respectively connected with the locking nuts.

[0008] After adopting the above scheme, the invention comprises a connecting block, an electric push rod, a first connecting rod, a second connecting rod and a swing arm. The first connecting rod, the second connecting rod and the swing arm constitute a group of connecting rod mechanisms, which can greatly increase the swing angle of the swing arm and has the advantages of small size and small mechanism. In addition, the invention is provided with locking nuts, which can be propped against the swing arm to lock the swing arm.

[0009] The invention will be further described in combination with the attached drawings and specific embodiments.Brief description of drawings

[0010] Fig. 1 is an axonometric view of the locking state of the invention; Fig. 2 is an axonometric view of the half range state of the invention; Fig. 3 is an axonometric view of the release state of the invention; Fig. 4 is a side view of the invention; Fig. 5 is a front view of the invention; Fig. 6 is a cross-sectional view of Fig. 5 along A-A line; Fig. 7 is a view of the invention in a locked state; Fig. 8 is a view of the invention in a released state. Detailed description of the invention

[0011] As shown in Fig. 1-fig. 6, the invention is an electric lifting mechanism with a safety device for an electric head of a wheelchair comprising a connecting block 1, an electric push rod 2, a first connecting rod 3, a second connecting rod 4, a swing arm 5, two locking nuts 6 and a locking bolt 7.

[0012] The upper end of the electric push rod 2 is hinged at the upper end of the connecting block 1, the pushing end part of the electric push rod 2 is hinged with the upper end of the first connecting rod 3 and the second connecting rod 4, the lower end of the first connecting rod 3 is hinged with the middle part of the connecting block 1, the lower end of the second connecting rod 4 is hinged with the upper part of the swing arm 5, the upper end of the swing arm 5 is hinged in the middle part of the connecting block 1, the hinge point of the swing arm 5 and the connecting block 1 is located at the upper part of the swing arm 5 above the hinge point of the upper part of the swing arm 5 and the lower end of the second connecting rod 4.

[0013] As shown in Figure 7-8, the middle part of the locking bolt 7 is transversely disposed and fixed at the lower end of the connecting block 1, the two ends of the locking bolt 7 protrude out of the connecting block 1 and two locking nuts 6 are respectively screwed at the two protruding ends of the locking bolt 7, the bottom surfaces of the locking nuts 6 are provided with circular chamfers 61, the lower end of the swing arm 5 is provided with a section of the inclined surface 51 and the chamfer 61 on the bottom surface of the locking nut 6 abuts against the inclined surface 51 of the lower end of the swing arm 5 to lock the swing arm 5.

[0014] The working principle of the invention: As shown in Fig. 1-fig. 3, when releasing, the locking nut 6 is rotated outwards to disengage the locking nut 6 from the swing arm 5; the push rod on the electric push rod 2 shrinks inwardly to drive the first connecting rod 3 and the second connecting rod 4 to swing upward, and the second connecting rod 4 drives the swing arm 5 to swing upward, so that the invention is in a released state.

[0015] The above is only a preferred embodiment of the invention and thus the scope of the present invention is not limited thereto. That is to say, modifications made in accordance with the scope of the claims shall still be within the scope of the patent for the invention.

Claims

1. An electric lifting mechanism for an electric head of a wheelchair comprising an electric push rod (2), a first connecting rod (3), and a swing arm (5), characterized in that it further comprises a connecting block (1), and a second connecting rod (4) wherein: - the upper end of the electric push rod (2) is hinged on the upper end of the connecting block (1); - the pushing end part of the electric push rod (2) is hinged with the upper end of the first connecting rod (3) and the second connecting rod (4) respectively; - the lower end of the first connecting rod (3) is hinged with the middle part of the connecting block (1); - the lower end of the second connecting rod (4) is hinged with the upper part of the swing arm (5); - the upper end of the swing arm (5) is hinged in the middle of the connecting block (1); and - the hinge point of the swing arm (5) and the connecting block (1) is located above the hinge point of the upper part of the swing arm (5) and the lower end of the second connecting rod (4) wherein it further comprises a safety device.

2. The electric lifting mechanism according to claim 1, characterized in that the safety device comprises at least one locking nut (6) and a locking bolt (7) wherein; - the middle part of the locking bolt (7) is transversely disposed and fixed at the lower end of the connecting block (1); - the two ends of the locking bolt (7) protrude out of the connecting block (1); - at least one of the two protruding ends of the locking bolt (7) is connected with the locking nut (6); - the bottom surface of the locking nuts (6) has circular chamfers (61); - the lower end of the swing arm (5) has a section of the inclined surface (51), and - the chamfer (61) on the bottom surface of the locking nut (6) abuts against the inclined surface (51) of the lower end of the swing arm (5) to lock the swing arm (5).