MULTI-SPEED TRANSMISSION WITH TWO PLANETARY GEARS

Abstract

A roughing grinding tool has a supporting body and at least one abrasive circle. The supporting body includes an abrasive grain for roughing grinding. The supporting body serves to support the at least one abrasive circle and itself for roughing grinding. The roughing grinding tool is easy to produce and robust and has a high removal capacity in conjunction with a long service life.

Claims

1. Multi-speed transmission mounted on a central axis with a hollow shaft on the input side and a hub sleeve on the output side and with two coaxially interposed or planetary gearboxes (EG, NSG) arranged coaxially therebetween or respectively therein, each with sun gear wheels, planetary gear wheels and hollow gear wheels connected to one another via associated webs, which can each be switched into a block revolution and several stepped conversion modes, wherein the first planetary gearbox (EG) is driven at its web and can be switched into a block revolution and several stepped conversion modes by means of three clutches can optionally be shifted into the block revolution or into said transmission modes by axle fixing of individual sun gears, and the second planetary gearbox (NSG) can be shifted into said transmission modes by means of further couplings by axle fixing of the sun gear with mutual shifting of the input and output between its ring gear and its ring gear respectively, and wherein the sun gear can be shifted into a slow and a fast mode as well as into the direct gear when the input and output are switched alternately between its ring gear and its web.

2. Multi-speed transmission according to claim 1, further comprising axially displaceable control slides, clutch rings extending radially and spring loaded in a coupling manner to be disengaged according to a respective gear step, wherein the control slides, guided in helical circular grooves in a coaxial shift drum and in radial slots of a hollow axis (6a) surrounding them and oriented parallel to the axis of rotation of the transmission, each actuate the associated clutch rings in a shifting manner

3. Multi-speed transmission according to claim 2, wherein the grooves are configured such that a nine-speed transmission with 40 degrees angular rotation per gear in total within only one revolution of the shift drum, can be set, whereby at least one intermediate shift combination is passed through.

4. Multi-speed transmission according to claim 3, wherein in four of the nine gears only one planetary set is activated and in four others of the nine gears both planetary sets are activated and in addition one of the gears, the direct gear, operates without rolling motion of the gears.

5. Multi-speed transmission according to claim 1, wherein the first transmission provides the speed conversions to i_1=1, i_2 approximately 0.81 and i_3 approximately 0.65 and the second transmission (NSG) provides the speed conversions to i_4 approximately 1.91, i_5=1 and i_6 approximately 0.52 such that there are largely constant gear steps of approx. 24% with a transmission ratio range of approximately 560%.

6. Multi-speed transmission according to claim 2, wherein the control slides are each guided by a cylindrical pin engaging in the associated groove and the radial slot oriented parallel to the axis of rotation of the transmission.

7. Multi-speed transmission according to the generic term of claim 1, wherein the first planetary gearbox (EG) is a three- or four-stage planetary gearbox, which is driven at its web and is switched in each case by means of a clutch by fixing an associated sun wheel into one of the said transmission modes, whereby a twelve- or fifteen-speed gearbox is formed in total.

8. Multi-speed transmission according to claim 2, wherein the clutch rings have a radial profiling which effects the power transmission.

9. Multi-speed transmission according to claim 8, wherein the radial profiling of the clutch rings, which are activated in only one direction of rotation, are asymmetrically profiled such that the pressure-loaded flanks are steeper than the flanks on the rear side thereof.

10. Multi-speed transmission according to claim 1, wherein the sun, planetary and ring gears, which are activated in only one direction of rotation, and have an asymmetrical profiling of the wheel teeth such that the flanks loaded by tensile force have a larger tooth engagement angle than the flanks at the rear thereof.

11. Multi-speed transmission according to claim 1, wherein the driver is equipped with a toothed belt or chain pinion which has a has a number of teeth which corresponds approximately to that of a correlated crank output blade.

12. Multi-speed transmission according to claim 11, wherein the toothed belt pinion has 34 teeth and the crank output blade has 42 teeth.

13. Multi-speed transmission according to claim 8, wherein the sun gear is axially fixed in both directions of rotation by only one clutch.

14. Multi-speed transmission according to claim 8, wherein the clutch parts to be coupled in both directions of rotation have a symmetrical profile and can thus set the sun gear axially fixed in both directions of rotation.

15. According to claim 2, wherein the structures of the helical grooves in the shift drum as well as the slots in the hollow axis, which serve for shifting all gears, are arranged on a maximum of 180 degrees of their circumferences and copies thereof are arranged on their other circumferential halves, in each of which a further cylindrical pin engages, which in each case actuates the associated coupling ring in parallel on the other side.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0012] FIGS. 1A and 1B illustrate a first gearbox of the transmission;

[0013] FIGS. 2A and 2B illustrate a second gearbox of the transmission;

[0014] FIGS. 3A and 3B illustrate a switching sequence table with associated legend;

[0015] FIG. 4 illustrates the total transmission including the first and second gearboxes in first gear;

[0016] FIG. 5 illustrates the total transmission including the first and second gearboxes in 5th gear;

[0017] FIG. 6 illustrates the total transmission including the first and second gearboxes in 9th gear;

[0018] FIG. 7 illustrates a perspective view of the drum;

[0019] FIG. 8 illustrates a side view of the shift drum;

[0020] FIG. 9 illustrates a perspective view of coupling half;

[0021] FIG. 10 illustrates a perspective view of the coupling half; and

[0022] FIG. 11 illustrates a perspective view of the clutch with the sun wheel.

DETAILED DESCRIPTION

[0023] A preferred design is a nine-gear transmission with constant gear steps of approx. 24% at a transmission ratio range of approx. 560%. The input transmission ratio is selected in such a way that with the secondary transmission ratio of the chain or belt drive with e.g. 40 teeth at the front and a rider with e.g. approx. 36 teeth at the transmission hub, a total transmission ratio i_ges for the first gear of approx. i_ges.=1.7 results. For the ninth gear this results in a transmission ratio of 0.30.

[0024] This is achieved by coupling two three-speed planetary gears.

[0025] A first transmission gear box is illustrated in FIG. 1a, which consists of a web or bridge 8 with double stepped planets 9a and 9b, a ring gear 7a with side wall 7b and two sun gears 9c and 9d, which mesh with the corresponding planets 9a and 9b, respectively. The bridge 8 is driven by a driver 4a, on which the pinion 2 is fixed rotationally. The output of the first gear is via the ring gear 7a. If the transmission is operated in block rotation, the direct gear with i_1=1 is obtained, and the gear ratio with i_2=1/1.24=0.8065 is obtained if the smaller of the two sun gears is fixed to the axis. The gear ratio with i_3=1/1.5376=0.65 is obtained when the larger of the two sun gears is fixed to the axis. Thus, the transmission ratio is fast.

[0026] A first preferred design of a second gear consists of two identical planetary gearboxes, mirrored to each other, each consisting of a ring gear, a sun gear and double stepped planets, which are coupled by means of bridges that are connected to each other in a rotationally fixed manner (not shown). The first subgear of this add-on set is a reduction gear with approx. i_4=1.24{acute over ( )}3=1.91 and the second subgear is a transmission gear with i_6−1/i_4=0.5245. The direct gear with i_5=1 is achieved when both subgears rotate as a block.

[0027] A second preferred version of a second transmission according to FIG. 2a consists of a planetary gearbox identical to a partial gearbox of the first preferred version. The three gears of the first preferred design are realized by switching the gear input between ring gear and web. The same procedure is used for the abrasion. This does not change the gear ratios.

[0028] The following table shows that in the case of gears G1, G5, G6, G7, only one planetary gear set is involved in the power transmission and in the case of gears G2, G3, G8 and G9 only two are involved. This stands for a good efficiency of the gear hub. Gear G4 does not require any rolling motion of the gears.

TABLE-US-00001 Transmission EG Transmission NSG Gear i_1 i_2 i_3 i_4 i_5 i_6 i_Gn 1 1 1.91 i.si 2 0.81 1.91 1.55 3 0.65 1.91 1.24 4 1 1 1 5 0.81 1 0.81 6 0.65 1 0.65 7 1 0.5245 0.53 8 0.81 0.5245 0.43 9 0.65 0.5245 0.34

[0029] According to the invention, the multi-speed transmission is shifted with axial clutches. A clutch is formed by two opposing discs, which can be operated by means of intermediate elements, with axially acting ratchet teeth acting in one direction, mounted on a circular ring perpendicular to the axis of rotation. In the following, a coupling that triggers the block rotation, “block lock”, which prevents the sun gear from rotating when driven by the web, “tracking lock” and which prevents the sun gear from rotating backwards when driven by the ring gear, “backstop”. In this case, the same direction of rotation as the driving belt or sprocket wheel is meant. If torque is to be transmitted with the same direction of rotation, the term “driver” is used.

[0030] In the following table the symbols used in the figures are listed with their meaning. In FIGS. 1b and 2b, the reference symbols of the couplings are counted through in steps of ten and those of the associated parts or elements in steps of one. In FIGS. 4, 5 and 6, which describe the shifting states of the gears G1, G5, G9, only the clutch numbers are then mentioned.

[0031] The preferred rear wheel hub, FIG. 1a,b and FIG. 2a,b, consists of a hub sleeve 1 supported by roller bearing 3a on the drive 4a and by roller bearing 3b on axle 6a. A drive pinion 2 for belt or chain drive is located on the drive 4a, rotationally fixed but detachably connected to it. The roller bearing 5 supports the drive 4a on the axle 6a. Inside the axle 6a there is a switching drum 6b (see also FIGS. 7 and 8). The oblong holes 101, 102, 103 and 104 are arranged parallel to the rotation axis and allow the cylindrical pins acting as actuators to pass through into the circumferential grooves 24, 34, 44, 54, 64, 74, 84 and 94 of the switching drum 6b. The grooves are designed in such a way that the intended movements of the shifting pins for shifting the individual gears are executed. The compression springs 22, 32, 42, 52, 62, 72, 82 and 92 are arranged in such a way that the clutches are always opened against the force of these springs. In an advantageous variant, a complete control structure is arranged on 180 degrees of the circumference of the shift drum and the hollow axle. This results in the great advantage that an exact copy of the same can be arranged on the second half of the circumference and thus the clutch plates can be controlled in parallel by means of second cylindrical pins. This prevents any shift inhibition due to a tilting load, which inevitably occurs with one-sided actuation.

[0032] The second NSG gear unit, FIG. 2a, consists of a drive sleeve 4b with internal and external toothing and at least one, but preferably two or three oblong holes 4c offset by 180 degrees or 120 degrees, an output sleeve 4d also with internal and external toothing and at least one, but preferably two or three oblong holes 4e offset by 180 degrees or 120 degrees. The drive sleeve is connected to the side wall 7b via the external gearing, and the abrasion sleeve is connected to the hub sleeve 1. The gear stage itself consists of the ring gear 200, the side walls 201a and 201b, at least one of which is designed to be connected to the ring gear 200 via a detachable connection, and also of the web 202 and the planets 203a and 203b, which are connected to each other in a rotationally fixed manner, and the sun gear 204. The planet 203a meshes with the ring gear 200 and the planet 203b with the sun gear 204, the side wall 201a is connected with the coupling part 51b and the side wall 201b with the coupling part 91b in a rotationally fixed manner. The coupling parts 61b and 81b are connected to the web 202 in a rotationally fixed but detachable manner. If the couplings are not engaged, the crosspiece and the ring gear can rotate freely.

[0033] The coupling components are numbered in the sequence in which they follow each other on axis 6a from the drive side in steps of ten, each starting with 20 to 90; FIG. 1a-2b and FIGS. 4-6.

[0034] Clutch 20 switches the block rotation of the first gear unit G1 by connecting or disconnecting the sun gear 9c to the drive 4a and thus to the web 8.

[0035] Clutch 20 shifts the gears G1, G4, and G7. The travel stop 21a engages the counterpart 21b, which is firmly connected to the sun gear, and prevents the sun gear from overrunning the web 8. The other components are a return spring 22, which is supported in the actuator 4a, a slider 23a with a cylindrical pin 23b, which is controlled by the groove 24.

[0036] The clutch 30 shifts the second gear of the first transmission by shifting the sun wheel 9c is set fixed to the axis. The clutch 30 shifts the gears G2, G5, and G7 of the overall transmission.

[0037] Clutch 40 shifts the third gear of the first transmission by setting the sun gear 9d to fixed position. Clutch 40 shifts gears G3, G6, and G9 of the overall transmission.

[0038] The sun gear 9d is designed as a ring with internal gearing in which the clutch part 41a (FIG. 9) designed as an anti-running clutch is guided in a rotationally fixed but axially displaceable manner. The counterpart 41b (FIG. 10) has internal teeth that connect it to the shaft 6a in a rotationally secure manner The retaining rings 45a and 45b prevent axial movement. A slider 43a with cylindrical pin 43b is controlled by the groove 44. The spring 42 is supported by a circlip 42a inserted in the axle 6a.

[0039] The clutches 50, 70, 80 shift the first gear of the second gear G2 by connecting clutch parts 51a (with cylindrical pin 51c) and 51b non-rotatably connecting the ring gear with the driver 4b, clutch parts 81b and 81a (with cylindrical pin 81c) non-rotatably connecting the web with the output sleeve 4d, and clutch parts or rings 71a (see also FIG. 11) and 71b setting the sun gear 204 axially fixed. The clutch rings 71a have a radial profiling which effects the power transmission. As shown in FIG. 11, the radial profiling of the clutch rings, which are activated in only one direction of rotation, are asymmetrically profiled such that the pressure-loaded flanks, i.e., clutch part 71a, are steeper than the flanks on the rear side thereof, i.e., clutch part 71b.

[0040] If this configuration is shifted, the gears G1, G2 and G3 are obtained together with the first gear.

[0041] The sun, planetary, and ring gears, which gears are activated in only one direction of rotation, and have an asymmetrical profiling of the wheel teeth such that the flanks loaded by tensile force have a larger tooth engagement angle than the flanks at the rear thereof.

[0042] The other components of the clutch 50 are a return spring 52 supported on the side wall 7b, a groove ring 53 with inner collar, a slider 55a with a cylindrical pin 55b controlled by the groove 54.

[0043] The clutch 70 is designed as a bidirectional clutch, since the direction of the torque is reversed when the input is switched from the ring gear to the bar. The other components of the clutch 70 are, a return spring 72, which is supported on the outer collar of the slider 63a, a slider 73a with a cylindrical pin 73b, which is controlled by the groove 74.

[0044] The other components of the clutch 80 are a return spring 82, which is supported on the outer collar of the slider 94a, and a slider 83a with a cylindrical pin 83b, which is guided in the groove 84.

[0045] The couplings 50 and 90, FIG. 2a, connect the input (drive) sleeve 4b with the output sleeve 4d via the ring gear 200, thus bridging the gear unit. The same result is obtained by engaging clutches 60 and 80, with the web transmitting the torque. In both cases, the sun can remain fixed to the axle, but this is only used for shifting purposes for a short time due to the loss of power.

[0046] The following options are available for block rotation, whereby the sun wheel can always rotate freely by opening clutch 70.

[0047] Variant 1: Clutches 50, 60, 90 closed, clutch 70 open.

[0048] Variant 2: Clutches 50, 80, 90 closed, clutch 70 open.

[0049] Variant 3: Clutches 50, 60, 80, 90 closed, clutch 70 open.

[0050] Variant 4: Couplings 60, 80, 90 closed, coupling 70 open.

[0051] Variant 5: Couplings 50, 60, 90 closed, coupling 70 open.

[0052] Variant 4: Couplings 50, 60, 80 closed, coupling 70 open.

[0053] Some of the possibilities are used as examples in the suggested switching sequence. In this configuration the second gear of the second transmission is realized. Gears G4, G5 and G6 can then be shifted.

[0054] Clutches 60, 70, and 90 shift the third gear of the second transmission by connecting clutch parts 61a and 61b to the web 202 with the driver 4b in a rotationally fixed manner, clutch parts 91b and 91a (with cylindrical pin 91c) to connect the ring gear 200 with the output sleeve 4d in a rotationally fixed manner, and clutch parts 71a and 71b to set the sun gear 204 in an axially fixed manner.

In this configuration, the third gear of the second gear is realized. Gears G7, G8, and G9 can then be shifted.

[0055] The solution of the task underlying the invention allows the use of needle bearings for the bearing of all planets. Due to the high load capacity of the manual transmission, ratios of up to i=1 can be used between bottom bracket chainring and hub drive pinion.

[0056] The exclusive use of axial clutches allows particularly good opening even under load. In most shifting operations, the clutches change to freewheel mode before they are opened, so that they can be opened without load. The number of different production parts is noticeably smaller than with the state of the art. The same applies to the total mass of the manual transmission. Due to the transmission structure, only a few gears are in mesh at any one time, which ensures high efficiency in the individual gears.