BRAKE

Abstract

A brake for a trolley that can brake rotation of a trolley wheel only in one direction. The brake includes a support connectable with a frame of the trolley, a first axle connected with another end of the support and peripherally provided with three indents, a pivotal first handle with a detent, wherein the first handle on the first axle can assume three positions defined by the three indents, a pin connected with the first handle and arranged parallel to the first axle, an eccentric ring with a recess, through which the pin projects, wherein the eccentric ring is pivotally mounted on the first axle and can engage with the outer periphery of the pulley wheel, a tension spring connecting the inner periphery of the eccentric ring and the pin, and a stop element projecting from the first axle, which can lean against the inner periphery of the eccentric ring. The brake enables unidirectional braking of a trolley either in forward movement or in rearward movement.

Claims

1. A brake for a trolley that comprises: a support connectable with its first end with a frame of the trolley, a first axle connected with another end of the support and peripherally provided with three indents, a first handle with a detent, said handle being pivotally arranged on said first axle, and wherein the first handle can assume three positions on the first axle, which are defined by the three indents, a pin that is firmly connected with one of its ends with the first handle and arranged parallel to the first axle at a radial distance therefrom, an eccentric ring with a closed bottom, in which at least an arcuate recess concentric with the first axle is formed, through which the pin projects, wherein the eccentric ring is pivotally mounted on the first axle and can engage with the outer periphery of a trolley wheel, a tension spring connecting the inner periphery of the eccentric ring and the pin, and a stop element projecting from the first axle, which can lean against the inner periphery of the eccentric ring thus preventing rotation of the eccentric ring around the first axle in one direction.

2. The brake according to claim 1, wherein, based on a selection by the user, the first handle with the detent can be positioned into three positions corresponding to three indents: a first end position, a second end position, and a middle position located between both end positions.

3. The brake according to claim 1, wherein the first handle with the detent, the tension spring, and the stop element are aligned when the first handle is in the middle position.

4. The brake according to claim 1, wherein the detent of the first handle is formed of a pressure spring and a ball that can engage with said three indents on the first axle.

5. The brake according to claim 1, wherein the eccentric ring is corrugated on its outer periphery.

6. The brake according to claim 1, wherein the eccentric ring is provided with a brake pad.

7. The brake according to claim 6, wherein the brake pad is corrugated from the outer side.

8. The brake according to claim 6, wherein the brake pad is formed of glass-fiber reinforced polychloroprene.

9. The brake according to claim 1, wherein the support is firmly connectable with the frame of the trolley.

10. The brake according to claim 1, wherein the support can be articulated with the frame of the trolley.

11. The brake according to claim 10, which further comprises a crank mechanism and a second handle, wherein the middle part of the holder is articulated via the crank mechanism with the second handle which can be articulated with the frame of the trolley, such that by moving the second handle the eccentric ring can be brought into a position of bidirectional braking of the trolley wheel, when the first handle is in the middle position.

12. The brake according to claim 1, which further comprises a cover, with which the eccentric ring can be covered.

13. The brake according to claim 1, which further comprises a first and a second permanent magnet, wherein the first permanent magnet is arranged on the first handle facing the eccentric ring, and the second permanent magnet is arranged on the eccentric ring opposite the first permanent magnet, when the first handle is in its middle position, wherein the first and the second permanent magnets are oriented in a way to attract each other.

Description

[0022] FIG. 1: Brake in cross-section

[0023] FIG. 2: Brake in side view

[0024] FIG. 3: Brake with a crank mechanism in cross-section

[0025] FIG. 4: Brake with a crank mechanism in side view

[0026] FIG. 5a: Brake in a position of unidirectional braking

[0027] FIG. 5b: Brake in a released position

[0028] FIG. 6a: Brake with a crank mechanism in a position of bidirectional braking

[0029] FIG. 6b: Brake with a crank mechanism in a position of unidirectional braking

[0030] FIG. 7: Brake with an eccentric ring with a corrugated outer periphery

[0031] FIG. 8: Brake with an eccentric ring with a corrugated brake pad

[0032] FIG. 9: Brake with two permanent magnets

[0033] The invention is described in more detail hereinbelow.

[0034] The technical problem is solved by a brake 1 for a trolley that comprises: [0035] a support 2 connectable with its first end with a frame 32 of the trolley, [0036] a first axle 3 connected with another end of the support and peripherally provided with three indents 3a, [0037] a first handle 4 with a detent 5, said handle 4 being pivotally arranged on said first axle 3, and wherein the first handle 4 can assume three positions on the first axle 3, which are defined by the three indents 3a, [0038] a pin 6 that is firmly connected with one of its ends with the first handle 4 and arranged parallel to the first axle 3 at a radial distance therefrom, [0039] an eccentric ring 7 with a closed bottom 7a, in which at least an arcuate recess 7b concentric with the first axle is formed, through which the pin 6 projects, wherein the eccentric ring 7 is pivotally mounted on the first axle 3 and engages with the outer periphery of a trolley wheel 30, [0040] a tension spring 8 connecting the inner periphery of the eccentric ring 7 and the pin 6, and [0041] a stop element 9 projecting from the first axle 3, which can lean against the inner periphery of the eccentric ring 7 thus preventing rotation of the eccentric ring 7 around the first axle 3 in one direction.

[0042] Based on a selection by the user, the first handle 4 with the detent 5 can assume three positions corresponding to three indents 3a: a first end position, a second end position, and a middle position located between both end positions.

[0043] In the middle position, the eccentric ring is remote from the outer periphery 30 of the trolley wheel and the trolley wheel can freely rotate. In this position, the first handle 4 with the detent 5, the tension spring 8, and the stop element 9 are aligned. The tension spring 8 forces the eccentric ring 7 into the central position.

[0044] The detent 5 of the first handle 4 can be formed of a pressure spring 5a and a ball 5b that can engage with said three indents 3a on the first axle 3.

[0045] A shift of the first handle 4 from the middle position to the first end position causes a shift of the eccentric ring 7 such that the outer periphery of the eccentric ring contacts the outer periphery of the trolley wheel. While the trolley wheel 30 rotates in one direction it pushes the eccentric ring 7 away from the trolley wheel 30 against the force of the tension spring 8, wherewith the rotation of the trolley wheel is enabled. While the trolley wheel rotates in another direction it pushes the eccentric ring 7 against the trolley wheel 30 due to the blocking effect, wherewith the rotation of the trolley wheel is disabled. The stop element 9 leans against the inner periphery of the eccentric ring 7 and prevents further rotation of the eccentric ring around the first axle 3 and consequently too excessive blocking of the eccentric ring 7 against the trolley wheel.

[0046] When the first handle is shifted from the middle position to the second end position, the situation is similar to the above-identified one, only that unidirectional braking is here achieved in the opposite direction of the trolley wheel rotation.

[0047] The outer periphery of the eccentric ring 7 can be corrugated 7c, what improves the efficiency of braking in both dry and wet conditions. The eccentric ring 7 can further be provided on its outer periphery by a brake pad 10. The brake pad 10 can be corrugated from the outer side. The material of the brake pad 10 can be for instance glass-fiber reinforced polychloroprene.

[0048] The support 2 can be firmly connected with the frame of the trolley. Such brake is suitable to be arranged on a trolley that is already provided with a conventional bidirectional brake.

[0049] In a further embodiment, the support 2 can be articulated with the frame 32 of the trolley. In this case, the middle part of the support 2 is articulated with the crank mechanism 12 with the second handle 11 which can in turn be articulated with the frame 32 of the trolley. If the second handle is shifted, the eccentric ring 7 can, while the first handle 4 is in the middle position, additionally assume the position of the bidirectional braking of the trolley wheel 30.

[0050] The brake 1 can further comprise a cover 15, with which the eccentric ring 7 is covered.

[0051] The brake 1 can further comprise a first 33 and a second 34 permanent magnet, wherein 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 the first permanent magnet 33, when the first handle 4 is in its middle position. The first 33 and the second 34 permanent magnets must be oriented in a way to attract each other. It is the function of the permanent magnets to prevent oscillations of the eccentric ring 7 around the first axle 3 when the trolley moves on an uneven surface (e.g. sand); the eccentric ring 7, more precisely its brake pad 10, is herewith prevented from engaging with the outer periphery of the trolley wheel, what would cause an undesired braking of the trolley.