GB2300888A - Multi-speed hub for bicycles has actuating collar with claw teeth engaging sun gears - Google Patents

Description

1 MULTI-SPEED HUB 2300888 The invention relates to a multi-speed hub for a

bicycle having more than three speeds, of the kind comprising a housing, a spindle, a driver coaxial with the spindle and rotatable relative to the housing and the spindle, a planetary gearing arrangement having more than three gear ratios in a drive path between the driver and the housing, the ratios being selectable at will, clutch means in the drive path selectable at will, a toothed rod rotatably mounted in a central bore in the spindle, a rotatable control tube controlled by the toothed rod and having axially acting cams on a face, means for holding against rotation one of a small sun wheel and a large sun wheel of the gearing arrangement, and a back-pedalling brake device in driving connection with the driver and acting on the housing.

is DE-A-34 40 071 shows a five-speed hub for a bicycle of the kind set forth provided with an integral back-pedalling brake device. The planetary gearing is mounted as a whole in the housing and has planet wheels made as ratio wheels, of which the ratios can be coupled to the two sun wheels alternately through a manual 1 y-actuated control device, the sun wheels in their turn being capable of being held alternately against rotation with respect to the spindle. In the known hub'the manufacture, assembly and adjustment of the two-stage planetary gearing is relatively expensive. Moreover the planetary gearing, in its higher ratio positions, reduces the braking torque that can be applied by the back-pedalling brake.

4 DE-A-39 30 374 shows a multi-speed hub of the kind set forth having six speeds, of which the housing is driven from the drivefthrough two sets of planetary gears. A first set of planetary gears'Allows the 30 engagement of two gearing stages and a direct gear, -And' a second i 2 planetary gearing arrangement is used as a preliminary gear with only one ratio step and one direct drive. The aim here is to improve the braking action and reduce the cost. However it is not possible to prevent the brake being actuated both with and without the ratio of the preliminary gear, whereby the overall gearing shares in the transmission of the braking torque.

DE 28 19 471 shows a back-pedalling brake hub of the kind set forth having three ratios, in which the driving torque is transmitted from the driver through the planetary gearing and its annulus and through a roller freewheel to the housing. On backward movement a braking roller freewheel is actuated, bringing a braking ring into frictional engagement with the housing. The distinctive feature of the two roller freewheels is that, in addition to the frictional connection to the housing and the stationary hub, the rollers of both freewheels are coupled together through a single roller cage. Again in this hub the gearing takes part in the braking process on back-pedalling.

It is an aim of the invention to provide a multi-speed hub for a bicycle of the kind set forth having more than three speeds and an integral back-pedalling brake, which, with minimum expense, allows a number of ratios with an integral back-pedalling brake, and in which the planetary gearing does not take part in the braking process.

According to a first aspect of the present invention, in a multi speed hub for a bicycle of the kind set forth, a control sleeve is rotatable with the spindle but is axially movable relative thereto, and has an operative connection to the control tube, the control tube hav1111g an actuating collar with a first set of claw teeth on a face, and a second set of claw teeth, the first, face-mounted, set of claw teeth bein.g adapted to 3 engage with claws on the small sun wheel, and the second set of claw teeth being adapted to engage with claws on the large sun wheel.

The invention enables simple operation of a system comprising two planetary gears of which the first is of single-step form and serves as a preliminary gear to a second which is of two-step form and by means of which, in conjunction with a direct ratio, five ratios can be produced. Such a hub has hitherto been operated through the centre of the spindle only by using two or more actuating blocks operated independently of one another, so that it was difficult to use detent locks as the clutch means. The use of rotatable control tubes around the spindle has hitherto only been possible by expensive introduction of control movement between the driver and the spindle. In the present invention the toothed rod acting through the spindle transmits the control movement through the control tube to the planetary gearing. It is only necessary to provide a rotary member on one end of the spindle in order to engage all the different ratios and detent locks can be used as the clutch means. Arranging the back-pedalling brake directly on the driving side between the driver and the housing makes it possible to have braking which is free of any lost motion and independent of the ratio currently engaged.

Conveniently the toothed rod acts through pinions secured in the spindle to transmit the control movement to the control tube. The pinions provide a simple way of transmitting the movement.

Preferably the small sun wheel has a set of clutch teeth on its face which co-operate with a set of clutch teeth on a first'clutch ring, which is resiliently mounted to be secure against rotation but axially displaceable, to form an over-running clutch. Similarly, the large sun wheel has a set of clutch teeth on its face which co-operate with a set of clutch teeth on a 4 second clutch ring, which is resiliently mounted to be secure against rotation but axially displaceable, to form an over-running clutch.

According to a second aspect of the invention, in a multi-speed hub for a bicycle of the kind set forth, the drive rollers of a first roller freewheel are adapted to move into and out of jamming engagement between an annulus of the gearing arrangement and the housing by means of a first roller cage, the first roller cage being adapted to be frictionally connected either to the annulus or a sleeve.

Furthermore the driving of the housing through roller freewheels provides the advantage that when the cycle is freewheeling, that is to say when the rider is going downhill without pedalling, there are no resistances offered by clutches or by friction and accordingly the movement is free of noise.

Conveniently, a second sleeve has a shoulder on its face, which, on engagement of a fourth detent lock by displacement of the second sleeve in the direction towards the first roller cage, engages the first roller cage, to release the frictional connection of the first roller cage to the annulus and to take over the frictional connection to the first roller cage.

It has been found particularly advantageous in the use of a bicycle having the multi-speed hub, that on wheeling the bicycle backwards the pedals no longer turn as the housing is disengaged from the drive when there is no drive applied from the pedals.

Preferably, at least one ratio is engaged by operation of a detent lock. This to some extent, allows a gear change to be performed under full load. It is also possible for the rider to select and also engage any ratio as desired whilst at a standstill or when freewheeling.

According to a third aspect of the invention, in a multi-speed hub for a bicycle of the kind set forth having more than three speeds, a driving spindle of an electric motor is in operative contact through a gearbox with the toothed rod in the spindle.

The motor and the gearbox may be arranged in a housing connected 10 to the spindle.

The various aspects of the invention are illustrated by way of example in the embodiments shown in the accompanying drawings, in which: - is 1 Figure 1 is a longitudinal section through an embodiment of a ten-speed hub. for a bicycle having an integral back-pedalling brake and shown in the driving position with first speed engaged; Figure 2 shows a small and a large sun wheel of the hub of Figure 1, the large sun wheel being held; Figure 3 shows the sun wheels of Figure 2 with the small sun wheel held; Figure 4 shows an electric motor drive for a toothed rod; Figure 5 shows the drive of Figure 4 mounted on a spindle; and 6 Figure 6 shows a developed view of control cams and their relationship with the individual ratios.

Figure 1 shows a ten-speed hub for a bicycle with an integral backpedalling brake, having a housing 1 with a spoke-carrying flange and mounted to be rotatable with respect to a spindle 2. The housing 1 is adapted to be driven from a driver 4 which is rotatable in its turn relative to the spindle 2 and to the housing 1, the drive being through a gearing arrangement comprising two sets of planetary gearing. The driver 4 is driven through a driving sprocket 3 which is secured to it against rotational and axial movement. The driver 4 is supported through a first bearing 5 on a stationary cone 6 secured to the spindle 2. A second bearing 7 forms the connection with the housing 1 which in its turn is rotatably connected to the spindle 2 through a third bearing 8 and an adjustable cone 9.

The first set of planetary gearing comprises the driver 4 with an internally toothed ring 45 as the annulus, at least one planet wheel 12, a first planet carrier 10 and a sun wheel 18 rigidly connected to the spindle 2.

The second set of planetary gearing comprises an annulus 19, a second planet carrier 11, a double planet wheel 13 and small and large sun wheels 16, 17 respectively. The double planet wheel 13 has two stages, a large ratio wheel 14 and a small ratio wheel 15.

The first planet carrier 10 can be connected to a first sleeve 55 through a first detent lock 21; a second detent lock 22 connects the driver 4 likewise to the first sleeve 55, the second detent lock 22 being arranged on a first ring 54 which has a projection 54a engaging radially 7 inwards the first sleeve 55 at at least one slot 55a. This projection 54a is urged by spring force against a collar 32a on a first control sleeve 32 which is arranged by its engagement with the tooth of the sun wheel 18 to rotate with it but be axially displaceable. The spring force between the projection 54a and the collar 32a is achieved by a first spring 59 and an opposing second spring 60. The first spring 59 is provided with a larger spring force than the second spring 60, so that the first control sleeve 32 always remains in contact with a first control cam 28 on a control tube 27.

The first set of planetary gearing is actuated on every change of speed. Its ratio is set so that it reduces the difference in ratios of the second set of planetary gearing by about 25%. The second set of planetary gearing gives with its two sets of wheels 14 and 15 a five-speed gear, known in itself, with two low (hill-climbing) ratios, a normal ratio and two high ratios. By the reduction in the gap between the ratios there are obtained ten speeds if after each gear change in the five-speed gearing of the second set of planetary gears the first set of planetary gears is changed over and then is moved back again on a further change in the second set.

The control tube 27 is mounted rotatably on the spindle 2 and can be rotated from outside through a toothed rod 25 and at least one pinion 26. Each pinion 26 has two coaxial trunnions by which it is rotatably mounted in pockets 50 in the spindle 2. The first control cam 28 is directed towards the first set of planetary gearing and a second control cam 29 and a third control cam 30 are directed in an axial direction towards the second set of planetary gearing. A second control sleeve 33 co-operates with the second control cam 29. The second control sleeve 33 is urged by the spring force of a fifth spring 67 against the 8 second cam 29. A third control sleeve 34 co-operates with the third cam 30. The third control sleeve 34 is mounted by means of longitudinal splines 2a on the spindle 2 so as to rotate with it but to be axially displaceable. The third control sleeve 34 has in its turn on its outer periphery a set of wedge teeth 34a on which a second clutch ring 35 is mounted to rotate with it but to be axially displaceable. The wedge teeth 34a extend over the entire length of the third control sleeve 34 so that the second control sleeve 33 is mounted on them as well. A third spring 63 abuts against the second clutch ring 35 and urges a second sleeve 56 with a collar 57 against the second control sleeve 33, whereby the latter is axially displaced on rotation of the control tube 27. The second sleeve 56 is axially displaceable relative to the first sleeve 55 through the slot 55a. A third detent lock 23 and a fourth detent lock 24 are arranged on the outer diameter of the second sleeve 56. The third detent lock 23 can be coupled to the annulus 19 and the fourth detent lock 24 to the second planet carrier 11 so as to be rotatable with it in one direction. A first roller cage 54 of a first freewheel 36 is urged by the second spring 60 against a face 19a of the annulus 19, resulting in a frictional connection between the two components. The second sleeve 56 has on its mounting of the third detent lock 23 a shoulder 51 which, on movement of the second sleeve 56, slides up against the first roller cage 52 and releases the latter from its frictional engagement with the face 19a and itself takes over the frictional engagement with the first roller cage 52.

The third control sleeve 34 has on its end remote from the control tube 27 an actuating collar 48. The fifth spring 67 urges the third control sleeve 34 against the control cam 30 through a spring ring 49, this ring 49 being inserted in a groove on the outside diameter of the third control sleeve 34.

9 The actuating collar 48 (shown in more detail in Figures 2 and 3) represents an annular and increased-diameter termination of the third control sleeve 34; on its face adjacent the small sun wheel 16 there is a first set of claw teeth 48a and on its face adjacent the large sun wheel 17 there is a second set of claw teeth 48b. The first set of claw teeth 48a can be coupled to the claws 16a by movement of the third control sleeve 34 towards the small sun wheel 16. The second set of claw teeth 48b can be coupled to the claws 17a by movement of the third control sleeve 34 towards the large sun wheel 17. The small sun wheel 16 has, on its face opposite the claws 16a, some claws 16b which co-operate with a set of clutch teeth 31a on a first clutch ring 31 which is secured against rotation and is resiliently axially displaceable, forming an over-running clutch. The large sun wheel 17 has, on its face opposite the claws 17a, some claws 17b which co-operate with a set of clutch teeth 35a on the second clutch ring 35 which is secured against rotation and is resiliently axially displaceable, to form an over-running clutch.

The first clutch ring 31 is urged axially by a fourth spring 66 against the small sun wheel 16 which can rotate freely on the spindle 2, ensuring that, if the small sun wheel is held against rotation, the torque is transmitted to the spindle 2. If the large sun wheel 17 is held against rotation the small sun wheel 16 can only idle in the direction predetermined by the clutch teeth 16b131a. In an analogous manner the second clutch ring 35 is connected through a set of clutch teeth 35a to the claws 17b of the large sun wheel 17, whereby the clutch ring 35 is mounted for rotation with, but axially spring-loaded on, the wedge teeth 34a of the third control sleeve 34 and is spring-urged by the third spring 63 and the fifth spring 67 against the large sun wheel 17.

During the gear-changing process by the third control sleeve 34 and the securing against rotation by the actuating collar 48, the axial position of the sun wheels 16 and 17 is practically unaltered as the large sun wheel 17 is pressed against the face of the large ratio wheel 14 by the third and fifth springs 63, 67 and as the small sun wheel 16 is spring urged against the large sun wheel 17 by the fourth spring 66. The force of the fourth spring 66 is less than the combined force of the two previously mentioned springs 63 and 67, and accordingly the position of the two sun wheels 16 and 17 described earlier remains unaltered.

The gear-changing process itself can also take place - mainly when the gearing is at a standstill - even when the crests of the teeth are aligned. If the first claw teeth 48a and the claws 16a do not engage because they are not correctly aligned, the small sun wheel 16 is moved against the force of the fourth spring 66 and then springs back into the original position as soon as the correct tooth engagement is allowed by rotation of the second set of planetary gearing. If the second claw teeth 48b and the claws 17a of the large sun wheel 17 do not engage because they are not correctly aligned, the actuating collar 48 holds back and accordingly the third control sleeve 34 is urged by the fifth spring 67 out of position until, on rotation of the second set of planetary gearing, the correct tooth engagement is restored.

The second planet carrier 11 of the second set of planetary gearing is mounted in the annulus 19 on the drive side and has at that point a set of teeth 64 in which the fourth detent lock 24 can engage. The teeth 64 have on the planet-wheel side a lifting ramp 65 which acts on the displacement of the second sleeve 56 and accordingly of the fourth detent lock 24. The driving forces are transmitted from the second planet carrier 11 to the housing 1 through a second roller freewheel 37 having a second roller cage 53. The second planet carrier 11 can be coupled to the housing like the annulus 19 through the first roller freewheel 36.

The back-pedalling brake of the multi-speed hub comprises a braking roller freewheel 38 which is connected to the driver 4 through a first profile 47 and has a third roller cage 44 in frictional engagement with a brake lever 41. On back-pedalling, the brake roller freewheel 38 acts through the first profile 47 on a braking sleeve 39 which is slotted in at least one place in the direction of the line of the sleeve and is held together by a spring. The braking sleeve 39 is connected to the brake lever 41 through at least one follower surface 40, so that any circumferential forces which arise are transmitted through the brake lever 41 to the frame of the bicycle, when the lever 41 is itself connected to the frame.

is The actuation of the control tube 27 takes place from outside by arranging that an actuating member which can be operated by the rider rotates the toothed rod 25 in a central bore in the spindle 2. The pinions 26 then cause rotation of the control tube 27 with a reduction ratio of about 1: 3. The toothed rod 25 comprises a profiled bar with the desired tooth profile which must correspond to that of the pinions 26 provided within the spindle 2. They can accordingly be made from the same blanks or starting material as the rod 25. Internal teeth having a matching profile in the control tube 27 ensure a permanent engagement between toothed rod 25, pinion 26 and control tube 27.

To describe the operation of the ten-speed gear described above it is sufficient to explain the five speed steps of the second set of planetary gearing, which - as already stated - is doubled by an additional step each by the first set of planetary gearing. The additional ratio is achieved by 12 rotating the control tube 27 and shifting the first control sleeve 32, which uses its collar 32a to shift the first ring 54 in such a way that the second detent lock 22 engages in the detent teeth 20 of the driver 4, disengaging the conversion ratio of the first planetary gear. The first detent lock 21 then overruns the more slowly running first planet carrier 10. The five ratios of the second planetary gearing are identified as Iarge high gear, small high gear, normal gear, small hill-climbing gear and large hillclimbing gear". The clutch means comprise the first to fourth detent locks 21 to 24, and the two freewheels 36, 37.

The large high gear of the second planetary gear with five speeds is engaged when the planet carrier 11 is driven through the fourth detent lock 24 and the double planet wheel 13 abuts against the large sun wheel 17, which for this purpose is coupled to the gear-changing collar 48 of the third control sleeve 34 with the spindle 2. The more rapidly rotating annulus 19 transmits the movement to the housing 1 through the first roller freewheel 36.

The small high gear is engaged by rotating the control tube 27, causing displacement of the third control sleeve 34 to the left in Figure 1, so that the second set of claw teeth 48b on the collar 48 are disengaged from the claws 17b on the large sun wheel 17 and the second set of claw teeth 48b come into engagement with the claws 16a on the small sun wheel 16. The drive of the annulus 19 goes faster, but with a smaller conversion ratio.

Normal gear is a direct coupling of the housing 1 to the second sleeve 56 through the third detent lock 23 and the first roller freewheel 36, bypassing the second planetary gearing by moving the second control sleeve 33 to the right in Figure 1, causing the fourth detent lock 24 to 13 come into engagement with the teeth 64 and driving the housing 1 directly through the second roller freewheel 37 whilst bypassing the second planetary gear. The first roller freewheel 36 is still disengaged as the face 19a of the annulus 19 has frictional contact with the first roller cage 52, whereby there is no relative rotation with respect to the rollers of the first roller freewheel 36 that would lead to the running of the rollers on a second profile 62 on the annulus 19.

This situation only changes with the engagement of the small hill-climbing gear, when the second sleeve 56 is shifted to the right in Figure 1 through a small axial movement e (see Figure 6). In that case the shoulder 51 of the first roller cage 52 moves slightly to the right, disengaging the frictional contact with the face 19a and causing a frictional engagement with the shoulder 51. This causes more rapid rotation of the first roller freewheel 36 and its profile 62 with respect to the first roller cage 52 so that the drive rollers of the first roller freewheel 36 are urged backwards against the ramp faces of the profile 62, looking in the direction of rotation, so that the rollers are urged outwards to jam and produce friction between the annulus 19 and the housing 1. The higher rotational speed of the annulus 19 is generated through the driven fourth detent lock 24 which drives the annulus 19 into high speed through the planet carrier 11 and the double planet wheel 13.

The large hill-climbing gear (bottom gear) is introduced by moving the collar 48 back from its position coupling it to the small sun wheel 16 and into the position coupling it to the large sun wheel 17, the inverse of the foregoing description being applicable.

On a braking process caused by rotating the driver 4 backwards the path of the force is conducted through the braking roller freewheel 38 to 14 the braking sleeve 39, which makes a greater or smaller frictional connection to the housing according to the size of the torque applied. The braking takes place bypassing the first and second sets of planetary gearing, which come to a standstill, the housing 1 idling. The third roller cage 44 is connected to the brake lever 41 through a slight friction which urges the rollers of the brake roller freewheel against the ramp faces of the first profile 47 on backward pedalling movement, whereby they come into jamming engagement between the driver 4 and the braking sleeve 39, bringing the braking sleeve 39 outwards into contact with the housing 1 on further backward-acting back-pedalling brake movement. A bearing shell 43 is incorporated for mounting the brake device and for transmitting friction and a dust cover 42 is included through which the brake lever 41 passes.

is In the diagram shown in Figure 6 the five gear ratios of the second planetary gearing are indicated in Roman numerals and the ten ratios in Arabic numerals. The gear-changing movements of the first control sleeve 32, the second control sleeve 33 and the third control sleeve 34 are accordingly described progressively from the first to the tenth ratio from top to bottom. The first control sleeve 32 follows the first control cam 28, which changes over the ratio of the first set of planetary gearing continuously from the first to the tenth gear and so splits each of the five ratios of the second set of planetary gearing into two. Therefore the first sleeve 32 always moves back and forth on each gear change from the first to the tenth. The second control cam 29 which controls the second sleeve 33 is stationary in the first gears 1 and 11; for the normal gear Ill the fourth detent lock 24 is activated, but without releasing the first freewheel 36. Only in IV gear is the second control sleeve 33 moved further through an extra distance e, so that the first roller freewheel 36 takes over the drive between the annulus 19 and the housing 1. In this position the second control sleeve 33 remains unchanged and the first roller freewheel 36 does so for the ratios 8 to 10. This means that the flow of force is now through the first freewheel 36 to the housing 1, whereas in the preceding ratios the flow of force was transmitted to the sleeve 1 through the second roller freewheel 37. The movement of the third control sleeve 34 on the third control cam 30 has already been described: the control sleeve 34 holds the large sun wheel 17 in ratios 1 and 2, in ratios 3 to 8 it holds the small sun wheel 16 and f inally in the ratios 9 and 10 the large sun wheel 17 through its collar 48 on the spindle 10 against rotation in the abutting direction.

With reference to the diagram it should be pointed out that the first gear is the large hill-climbing gear (bottom gear) and the tenth gear is the highest top gear.

is Figures 4 and 5 show an electric motor drive for the toothed rod 25 mounted in a housing connected to the spindle 2. The drive comprises.an electric motor 70 whose driving spindle 71 is in operative contact through a gearbox 73 with the toothed rod 25 in the spindle 2. The motor 70 and the gearbox 73 are arranged in a housing 72 mounted on the spindle 2.

The motor 70 provides for easy operation of the hub.

16

Claims (11)

1. A multi-speed hub for a bicycle of the kind set forth with more than three speeds in which a control sleeve is rotatable with the spindle but is axially movable relative thereto, and has an operative connection to the control tube, the control tube having an actuating collar with a first set of claw teeth on a face, and a second set of claw teeth, the first, facemounted, set of claw teeth being adapted to engagement with claws on the small sun wheel, and the second set of claw teeth being adapted to engage with claws on the large sun wheel.

2. A multi-speed hub as claimed in claim 1, in which the toothed rod acts through pinions secured in the spindle to transmit the control movement to the control tube.

is

3. A multi-speed hub as claimed in claim 1 or claim 2, in which the small sun wheel has a set of clutch teeth on its face which co-operate with a set of clutch teeth on a first clutch ring, which is resiliently mounted to be secure against rotation but axially displaceable, to form an over- running clutch.

4. A multi-speed hub as claimed in any preceding claim, in which the large sun wheel has a set of clutch teeth on its face which co-operate with a set of clutch teeth on a second clutch ring, which is resiliently mounted to be secure against rotation but axially displaceable, to form an overrunning clutch.

5. A multi-speed hub for a bicycle of the kind set forth having more that three speeds, in which the drive rollers of a first roller freewheel are adapted to move into and out of Jamming engagement between an annulus 17 of the gearing arrangement and the housing by means of a first roller cage, the first roller cage being adapted to be frictionally connected either to the annulus or a sleeve.

6. A multi-speed hub as claimed in claim 5, in which a second sleeve has a shoulder on its face, which, on engagement of a fourth detent lock by displacement of the second sleeve in the direction towards the first roller cage, engages the first roller cage, to release the frictional connection of the first roller cage to the annulus and to take over the 10 frictional connection to the first roller cage.

7. A multi-speed hub for a bicycle of the kind set forth having more than three speeds in which a driving spindle of an electric motor is in operative contact through a gearbox with the toothed rod in the spindle.

is

8. A multi-speed hub as claimed in any preceding claim, in which at least one ratio is engaged by operation of a detent lock.

9. A multi-speed hub as claimed in claim 8, in which the motor and 20 the gearbox are arranged in a housing connected to the spindle.

10. A multi-speed hub for a bicycle of the kind set forth substantially as described herein with reference to and as illustrated in Figures 1 to 3 and 6 of the accompanying drawings.

11. A multi-speed hub for a bicycle of the kind set forth substantially as described herein with reference to and as illustrated in Figures 4 and 5 of the accompanying drawings.