WO2002035111A1

WO2002035111A1 - Roller-claw free-wheel clutch

Info

Publication number: WO2002035111A1
Application number: PCT/SK2000/000022
Authority: WO
Inventors: Roman BOHACÍK
Original assignee: RB DESIGN SRO
Current assignee: RB DESIGN SRO
Priority date: 2000-10-27
Filing date: 2000-10-27
Publication date: 2002-05-02
Anticipated expiration: 2003-04-27
Also published as: AU2001213230A1

Abstract

The roller-claw free-wheel clutch is composed (Drawing 1) of external ring (1) bearing claws (6) between which rollers (3) fit in which are pushed against the external ring by a spring (4). In gear of the clutch the surface (9) of internal ring (2) is pushed against rollers (3). In idling run (picture 2) rollers (3) are carried by claws (8) situated on internal ring (2) through claws (6) situated on external ring (1) and at the same time, they are pushed by claws (6) in the space between a claw (8) and a surface (9).

Description

Roller-claw free-wheel clutch

Technical Field

The invention concerns a roller-claw free-wheel clutch allowing to connect and disconnect driving and driven parts of a machine by a mere change of relative speed between driving and driven parts. It is particularly suitable for devices where smaller dimensions are desirable and a relatively larger torsional moment is transmitted. For example, in hubs of bicycle wheels. Background Art

Until now free-wheel clutches working on the principle of claws and latches are commonly used, mostly in hubs of bicycle wheels. One of disadvantages of this system is that latches don't fit into claws uniformly. The reason can be found in the structure of this system. In gear of the clutch it may happen that a latch does not fit completely into a claw but it gets stuck on its edge, which leads to a displacement or breakage of the claw. In addition, in gear only one latch may fit in; two to four latches are usually used because one claw cannot transmit the torsional moment and comes off.

Further free-wheel self-locking roller clutches are often used. A disadvantage of this system is that in case of a small displacement or wear of surfaces coming into contact with rollers the clutch will start to slip. Disclosure of invention Deficiencies indicated in the section „Actual state of technology" are completely or mostly eliminated by a roller-claw free-wheel clutch. This means that rollers fit in between claws so the clutch cannot slip in case of wear or displacement of contact surfaces as with the free-wheel self-locking roller clutch. In fact the rollers fit in between claws at the same time and when the clutch gets into gear, i. e. is connected, the rollers are always fitted in between claws so the situation as in case of a free-wheel clutch with claws and latches cannot occur. The parallel fitting of rollers in between claws is secured by the form of claws, their geometry and a spring that pushes the roller against claws between which the rollers fit in. Another advantage of this free-wheel clutch is that for smaller dimensions it can transmit relatively large torsional moment. Brief Description of Drawings Drawing No.1/7 - FIG. 1 - front view of the roller-claw free-wheel clutch No.2/7 - FIG. 2 - detail A

No.37 - FIG. 3 - drawing of free-wheel clutch in gear

FIG. 4 - dawing of free-wheel clutch in idling run No.4/7 - FIG, 5 -drawing of free-wheel clutch at the moment between idling run and gear (so-called end play)

No.5/7 - FIG. 6 - sectional view A-A FIG. 7 - sectional view B-B No.6/7 - FIG. 8 - detail variant of claws shape No.7/7 - FIG. 9 - detail of free-wheel clutch in gear FIG. 10 - detail of free-wheel clutch in idling run

Best Mode for Carrying Out the Invention

The device on the drawing No.1/7, FIG. 1, is composed of external ring of free-wheel clutch 1, internal ring of free-wheel clutch 2, connecting segments - rollers 3 and spring 4. The gear of roller-claw free-wheel clutch occurs in the same way as for other types of free-wheel clutches where relative rate of rotation of the external (1) and internal (2) rings (drawing No.3/7, FIG. 3) or the action of torsional moment go in opposite direction. The roller-claw free-wheel clutch is in gear (drawing No.2/7, FIG. 2 and drawing No.3/7, FIG. 3) when the rollers 3 are fitted in between claws 6 that can have the shape illustrated on the drawing 6/7, FIG. 6, or when between claws there is radius 7 (drawing No.2/7, FIG. 2) equal to or larger than radius of rollers 3 and the surface 9 is pushed against the rollers (drawings No. 2/7 and 3/7, FIG. 2 and 3). The angle A - drawings No.2/7 and 6/7, FIG. 2 and 8 - should be equal to zero or more degrees. The uniform fitting of rollers 3 between claws 6 is caused by a spring 4 that is located in the slot 10 (drawing No.5/7, FIG. 6 A-A) and that pushes the rollers 3 against the external ring of free-wheel clutch 1, a well as by the shape of claws 6 and angle B which should be equal to at least 90 degrees.

In case of idling run the external ring 1 and the internal ring 2 turn in opposite direction than in case of gear (drawing No.3/7, FIG. 4). In idling run rollers 3

(drawing No.3/7, FIG. 4) are carried by claws 8 on the internal ring 2 through claws 6 of the external ring 1 (drawing No.3/7, FIG. 3). The gaps between claws

8 and surfaces 9 must be large enough so that rollers 3 (in this case pushed in by claws 6) fit into them. The slot 10 (drawing No.5/7, FIG. 6) must be large enough to allow free movement of the spring 4 at the motion of roller 3 in idling run. The spring 4 is anchored in the opening 5 (drawing No.1/7, FIG. 1, drawing No.57, FIG. 7 B-B) to avoid its rotation at the motion of the free-wheel clutch. At the moment which occurs between idling run and gear, so-called end play (drawing No.4/7), where rollers 3 are not more carried by claws 8 and contact surfaces 9 don't push yet against rollers 3, the latter are always fitted in between claws 6. For this reason it cannot happen that rollers 3 got stuck in interposition on the edge of claws 6, push against it and cause a destruction of claws 6.

The number of rollers 3 used in the roller-claw free-wheel clutch is at least 2-3 or larger, as allowed by the size of free-wheel clutch and dimensions of rollers 3. The length of rollers 3 should be at least 1.5-multiple of the roller's diameter to prevent their crossing. The number of claws 6 on the external ring 1 depends on the diameter of rollers 3, angle A and size of free-wheel clutch. In general the rule applies that the larger is the number of claws the relatively shorter is idling run of free-wheel clutch.

Industrial Applicability

The roller-claw free-wheel clutch can be used for industrial purposes in all machines where a large torsional moment should be transmitted. For example in machines where small dimensions of free-wheel clutch are desirable, e. g. in hubs of bicycle wheels.

Claims

1. The roller-claw free-wheel clutch enabling the connection and disconnection of driving and driven parts of a machine by a mere change of relative speed between driving and driven parts, characterised by the fact that rollers (3) fit in between claws (6) on the external ring of free-wheel clutch (1) with a radius (7), are pushed against the external ring of free-wheel clutch by a spring (4) and in idling run of the clutch rollers (3) are carried by claws (8) on the internal ring of free-wheel clutch (2) whereby angle B is equal to 90 degrees or larger.

2. The roller-claw free-wheel clutch meeting the requirement 1, characterised 0 by the fact that in gear of free-wheel clutch surfaces (9) push against rollers (3) that are fitted in between claws (6) whereby angle B is equal to zero degrees or larger.

3. The roller-claw free-wheel clutch meeting the requirement 1 or 2, characterised by the fact that radius (7) between claws (6) is equal to or larger 5 than radius of the roller (3).

4. The roller-claw free wheel clutch meeting the requirement 1 or 2, characterised by the fact that radius (7) between claws (6) is equal to or smaller than radius of the roller (3).

5. The roller-claw free-wheel clutch meeting the requirement 1 or 2 or 3 or 4, o characterised by the fact that the number of rollers (3) is equal to 2 or larger.