WO2000022315A1

WO2000022315A1 - Free wheel

Info

Publication number: WO2000022315A1
Application number: PCT/DE1999/003128
Authority: WO
Inventors: Frank Weidner
Original assignee: Frank Weidner
Priority date: 1998-10-08
Filing date: 1999-09-29
Publication date: 2000-04-20
Also published as: EP1045997A1; DE19948866A1; AU1373400A

Abstract

Disclosed is a free wheel comprising two tilting clamping elements (14) that are arranged between the cylindrical running surfaces of two rotating parts (9, 11) that can move in relation to each other in order to create a rotating connection, whereby said clamping elements (14) are pressed against the running surfaces by spring elements (29) arranged therebetween.

Description

Freewheel

State of the art

The invention is based on a freewheel with evenly distributed between a cylindrical inner part and a cylindrical outer ring rotatable about the same axis of rotation, guided over a bracket and tiltable about parallel to the axis of rotation tilting clamps, according to the preamble of the main claim.

Such freewheels are designed as non-positive clutches that transmit torque in one direction and allow idling or freewheeling in the opposite direction. For the torque transmission, the clamping bodies are tilted or slightly rotated about their tilting axis located in the center of gravity of the clamping body, whereby the inner part is clamped in the outer ring. In the freewheeling direction, on the other hand, the clamping bodies are rotated or tilted about the tilt axis in the other direction, whereby on the one hand the clamping is released, on the other hand the readiness for clamping is maintained and the clamping bodies are moved Work surfaces are easily held on the running surfaces of the inner part and outer ring, so that when the direction of rotation of the inner part or outer ring changes, which can also take the form of a relative change in the rotational angular velocity of the two parts, a non-positive coupling is produced again.

In a generic known freewheel (DE OS 1915567), a cage with two rings connected to one another via webs is used as a holder, the clamping bodies being arranged such that they can be tilted between the webs and these clamping bodies are loaded via winding springs arranged on their tilting axis. Due to the coil springs arranged in the axis next to the clamping bodies, this is at the expense of the possible total length of these clamping bodies and thus at the expense of the available friction line or pressing line between the working surface and the running surface and thus at the expense of the clamping quality. In addition, this type of suspension is complex, both in the assembly and in the manufacture of the individual parts.

The invention and its advantages

The freewheel according to the invention with the characterizing feature of the main claim has the advantage that, in addition to very inexpensive manufacture and assembly, there is also a very precise coupling with a minimum of slip. The arrangement of the spring element between the clamping bodies enables a particularly exact limitation of the tilting positions and thus a very quick and precise intervention when changing the relative rotational position of the inner part and outer ring. In addition, a quieter, but above all low-friction run is achieved by the invention. Especially in case of unsteady running, any resilient movement or running disturbance of the inner part and / or outer ring is dampened or. balanced again. According to an advantageous embodiment of the invention, the spring elements are sleeve-shaped, on the one hand to be easy to assemble and on the other hand to form a positive fit with the clamping bodies.

According to a further advantageous embodiment of the invention, the guide surfaces of the clamping bodies are convex in the region of the points of attack of the spring elements, so that the spring elements resting on these guide surfaces are guided in the radial direction.

According to a further advantageous embodiment of the invention, the spring elements are arranged on pins of a freewheel cage which is free-running with respect to the inner part and outer ring and has side parts. This gives the spring elements a guided division, which has a direct effect on the division of the clamping bodies and also on their tilting limitation, which in turn reduces slip.

According to a related embodiment of the invention, the side parts consist of disks which are connected to one another to form the freewheel cage via the pins.

According to a further embodiment of the invention in this regard, the pins each have a transverse division which is designed as a plug connection, the pins being firmly connected to the side parts by the end facing away from the plug connection. In its function as a simple holder of the spring elements, the freewheel cage is hardly subjected to bending or connection. Dynamic loads can only occur at higher speeds, which then make the use of such a divided free-wheel cage impossible. Advantageously, in the case of the divided freewheel cage, sleeves designed as a closed ring can also be licked onto the individual partial pins before the two are removed Freewheel cage halves are connected to each other via the plug connections.

According to a further embodiment of the invention in this regard, a plug which is arranged at the free end of a partial pin and is formed by tapering can be plugged into a corresponding axial bore of the corresponding free end of the opposite partial pin. Of course, other types of connectors are also conceivable.

According to a further embodiment of the invention in this regard, the free ends of the partial pins arranged next to one another alternately have a pin or an axial bore. In this way, the individual halves of the freewheel cages can be of identical design, which would require only one tool, particularly in the case of production from plastic or by injection molding from plastic or metal, and also mean no special attention for two different parts to be assigned.

According to a further embodiment of the invention, the spring elements and / or the freewheel cage are made of metal, plastic, rubber or the like, the required spring force or elasticity being relatively low due to the design of the invention.

According to a further embodiment of the invention, the clamping bodies are produced in the S extrusion process by creating a strand which has the working surfaces and guide surfaces and is subsequently cut into the corresponding length of the clamping bodies.

According to a further advantageous embodiment of the invention, the tilting axis of the clamping bodies runs approximately in the cylindrical center plane between the running surfaces, the tilting axis corresponding to the center of gravity axis. According to a related embodiment of the invention, the working surfaces of the clamping bodies are partially cylindrical, a first radius between the first working surface facing the outer ring and its cylinder axis largely starting from the tilting axis or the center of gravity axis, while a second radius between the other second partially cylindrical working surface and the latter Cylinder axis is much longer than the first radius.

According to a further embodiment of the invention in this regard, the cylinder axis of the first working surface runs largely in the middle between the guide surfaces, while according to another further embodiment of the invention the cylinder axis of the second working surface extends into the area between the cylindrical center plane and the outer ring field and opposite the radial center plane of the clamping body

Further advantages and advantageous embodiments of the invention can be found in the following description, the drawing and the claims.

drawing

An embodiment of the object of the invention is shown in the drawing and described in more detail below.

Show it:

1 is a bicycle hub in longitudinal section,

2 shows a partial section along the line II in FIG. 1,

3 is a perspective view of a cage of the freewheel, 4 a spring element in a perspective view,

Fig. 5 shows a clamping body, also in a perspective view

Fig. 6 shows a two-part freewheel cage in an exploded view

7 and 8 partial sections according to section II in Figure 1, once in the clutch position and once in the freewheeling position.

Description of the embodiment

In the freewheel hub shown in FIG. 1, a coaxially arranged hub body 4 is rotatably mounted on a wheel axle 1, which is connected to the bicycle frame via end pieces 2, and a freely rotatable rotor 6, on which, is also coaxially arranged via three ball bearings 5 again via two ball bearings 7 the other end of the hub body 4 is relatively rotatably supported. In this way, the hub body 4 and the rotor 6 can be rotated relative to one another and also relative to the wheel axis 1. The ball bearings 3 and 5 are fixed in their axial position via spacer sleeves 8. The usual sprockets for gear shifting are arranged on the rotor 6. A freewheel carrier shaft 9 is arranged coaxially to the wheel axle 1 and a freewheel outer ring 11 between which the freewheel 12 according to the invention is arranged, which is secured by a pull-off and counter ring 13. The freewheel 12 ensures that there is a freewheel in the one relative direction of rotation between the hub body 4 and the rotor 6, while in the opposite relative direction of rotation or corresponding rotational direction resulting from different speeds, a non-positive clutch in the freewheel 12 is effective, through which the hub body 4 and the rotor 6 are rotationally coupled to one another. In the partial section shown in FIG. 2 through the freewheel 12 corresponding to section II in FIG. 1, a part which is decisive for the clutch is shown on a greatly enlarged scale and in cross section, namely a clamping body 14 between the freewheel carrier shaft 9 and the freewheel outer ring 11, each of which have a tread 15 and 16 facing each other. The clamping body 14 is partially cylindrical on the sides facing the running surfaces 15 and 16, namely with a first working surface 17 and a second working surface 18. The clamping body 14 can be easily tilted about a tilt axis 19, which also forms the center of gravity axis, whereby due to the different axes of the Teilzy cylinder, or the length of the radii forming a change in distance between a first point of attack 21, between the working surface 17 and the tread 16 and a second point of attack 22 between the working surface 18 and the tread 15 results in a tilting. The tilt axis 19 lies approximately on an annular central plane I between the running surfaces 15 and 16. Moreover, the two working surfaces 17 and 18 are connected to one another via guide surfaces 23 which have convex curvatures. In order to achieve a fast action between the freewheel and the rotational connection between the freewheel carrier shaft and the freewheel outer ring, the friction force having to be greater than the tangential force after only a slight tilt, the assignment of the tilt angle, radius of the working surfaces and their position must meet certain conditions. For example, the radius 24 of the partial cylinder formed by the working surface 17 is shorter than the radius 25 of the partial cylinder formed by the working surface 18. In addition, the fulcrum of the radius 24 is approximately in the tilt axis 19, while the fulcrum of the radius 25 lies further up at 26, namely between the central plane I and the running surface 16 and is also shifted to the right in the direction of rotation 27 of the freewheel outer ring 11 in the drawing. This means that even with small twisting movements in Direction of rotation 27 of the freewheel outer ring 11 and / or a corresponding rotational movement in the direction of rotation 28 of the carrier shaft 9 of the clamping body 14 is moved into the position shown in FIG. 2, in which rotational connection between the freewheel outer ring 11 and the freewheel carrier shaft 9 occurs. As can easily be seen, the clamping body 14 is tilted even with slight opposite twisting movements, as a result of which a freewheel is again created between the two parts.

3, 4 and 5, the essential parts of the freewheel are shown in perspective, namely, in addition to one of the clamping bodies 14, a sleeve-shaped spring element 29 and a freewheel cage 31, in which 32 pins 33 are provided between two washers for connecting them. In the installed state, the spring elements 29 are arranged on the pins 33 and the clamping bodies 14 are inserted between the spring elements 29 and are thereby held. Due to the position of the guide surfaces 23 relative to one another, the clamping bodies 14 are held slightly inclined to their radial plane III in the installed state, in order thereby to obtain the sensitive tilting position shown in FIG. Through the washers 32, an axial displacement of the spring element 29 or the clamping element 14 is achieved, whereby the latter can be a radially resilient metal sleeve or else made of rubber or another elastic material in order to obtain the tangential form fit between the clamping element 14 and the spring element 29.

FIG. 6 shows a divided freewheel cage 31 in which the pins 33 are divided in two in the longitudinal direction, each with a pin 35 at the free end or an axial bore 36 in the correspondingly assigned pin. In this way, a plug connection 34 is formed for each pin combination, whereby the ring disks 32 are connected by simply plugging pins 35 into axial bore 36 with each other. On the individual pin sections 33, viewed on the circumference of the annular disks 32, one pin section is always provided with a pin 35 and the next with an axial bore 36, so that the two halves of the freewheel cage 31 are absolutely identical.

FIGS. 7 and 8 now show how the clamping bodies 14 are tilted about their respective tilting axis 19 when they are rotated accordingly. In Figure 7 there is a rotational connection between the freewheel carrier shaft 9 and the freewheel outer ring 11 according to the directions of rotation 27 and

28 of these parts, as well as it is shown in Figure 2. The spring elements 29 arranged on the pins 33 are relaxed because the clamping bodies 14 are tilted in the clamping position. It is different in Figure 8 when freewheeling. The relative rotation of the parts 1 1 and 9 is now reversed according to the directions of rotation 27 and 28, so that the rotating body more strongly on the spring elements

29 are tilted, with the tendency of the spring action to counteract this tilting, so that, as soon as a change in the direction of rotation takes place, the clamping bodies are rotated again into the position shown in FIG.

All features shown in the description, the following claims and the drawing can be essential to the invention both individually and in any combination with one another.

LIST OF REFERENCE NUMBERS

1 wheel axis 27 direction of rotation of 11

2 end pieces 28 direction of rotation of 9

3 ball bearings 29 spring element

4 hub bodies 30

5 ball bearings 31 freewheel cage

6 rotor 32 washers

7 ball bearings 33 pins

8 spacers 34 plug connection

9 freewheel carrier shaft 35 journal

10 36 axial bore

11 Freewheel outer ring

12 freewheel I middle plane

13 peel and II section in Figure 1

Lock ring III radial plane

14 sprags

15 tread

16 tread

17 first work surface

18 second work surface

19 tilt axis

20th

21 first point of attack

22 second point of attack

23 guide surface with convex

Vaults

24 radius

25 radius

26 fulcrum

Claims

Freewheel

Expectations

Freewheel

- With evenly between a cylindrical inner part (9) and a cylindrical outer ring (1 1) which can be rotated about the same axis of rotation, is guided by a holder (29) and has lateral surfaces (17, 18, 23) parallel to the axis of rotation and which extends parallel to the axis of rotation Tilting axles (19) tiltable clamping bodies (14),

- With the mutually facing treads (15, 16) of the inner part (9) or the outer ring (1 1) facing concave or beveled working surfaces (17, 18) on the clamping bodies (14) and the working surfaces (17, 18) with each other connecting guide surfaces (23) facing the holder,

- In the one tilt position of the clamping body (14) a freewheel between the inner part (9) and the outer ring (1 1) there is, while in the other, by changing the relative rotation of the inner part (9) and outer ring (1 1) relative to one another, the inner part (9) and outer ring (1 1) are rotatably coupled to one another against relative rotation by the clamping bodies (14), characterized in that that as a holder between the individual clamping bodies (14) and parallel to these elastic spring elements (29) are arranged which engage at a distance from the running surfaces (15, 16) on the guide surfaces (23) of the clamping bodies (14).

2. Freewheel according to claim 1, characterized in that the spring elements (29) are sleeve-shaped.

3. Freewheel according to claim 1 or 2, characterized in that the guide surfaces (23) in the region of the attack of the spring elements (29) are convex.

4. Freewheel according to one of the preceding claims, characterized in that the spring elements (29) on pins (33) with respect to the inner part (9) and outer ring (1 1) freewheeling and side parts (32) having freewheel cage (31) are arranged.

5. Freewheel according to claim 4, characterized in that the side parts consist of disks (32) which are connected to form the freewheel cage (31) via the pins (33).

6. Freewheel according to claim 4 or 5, characterized in that the pins (33) each have a transverse division, which is designed as a plug connection (34) and that the pins (33) with the end of the plug connection (34) facing away firmly with the side parts (32) are connected.

7. Freewheel according to claim 6, characterized in that as a plug-in connection (34) arranged at the free end of a partial pin, resulting from tapering pin (35) in a ne en tsp speaking end A xi alb oh ru ng (36) de s corresponding free end of the opposite pin part is pluggable.

8. Freewheel according to claim 7, characterized in that the free ends of the partial pins arranged side by side alternately have a pin (35) or an axial bore (36).

9. Freewheel according to one of the preceding claims, characterized in that the spring elements (29) made of metal, plastic, rubber or the like. consist.

10. Freewheel according to one of the preceding claims, characterized in that the clamping bodies (14) are produced in the extrusion process, by creating a the work surfaces (17, 18) and guide surfaces (23) having S strands, which subsequently in the corresponding length of the Clamping body is cut.

1 1. Freewheel according to one of the preceding claims, characterized in that the tilting axis (19) of the clamping bodies (14) extends approximately in the annular central plane (I) between the running surfaces (15, 16).

1 2. Freewheel according to claim 1 1, characterized in that the working surfaces (17, 18) of the clamping body (14) are partially cylindrical, a first radius (24) between the outer ring (1 1) facing the first working surface (17) and whose cylinder axis largely originates from the tilt axis (19), while a second radius (25) between the other second partially cylindrical working surface (18) and its cylinder axis (26) is significantly longer than the first radius (24).

1 3. Freewheel according to claim 12, characterized in that the cylinder axis (19) of the first working surface (17) extends largely in the middle between the guide surfaces (23).

14. Freewheel according to one of claims 1 1 to 13, characterized in that the cylinder axis (26) of the second working surface (18) falls in the region between the cylindrical central plane (I) and the outer ring (1 1) and with respect to the radial central plane (III) of the clamping body (14) is displaced in the clamping direction.

15. Freewheel according to one of the preceding claims, characterized by its use in vehicles, in particular bicycles, the inner part (9) being designed as a freewheel sleeve (freewheel carrier shaft 9) mounted on a tarrachs e (1).