FR2602294A1 - PALIERS GEARBOX - Google Patents

Abstract

THE SUBJECT OF THE INVENTION IS A GEARBOX FOR HEAVY VEHICLES. IN A GEARBOX CONFORMING TO THE INVENTION N2 COUPLING DISCS 13, 14, 15 OF AN INPUT CLUTCH E ARE PROVIDED, WITH A SET OF N2 ANNULAR CONTROL PISTONS 16, 17, 15, IN A COUPLING BOX 9, 12 DRIVEN IN CONTINUOUS ROTATION BY DRIVE ORGANS 2,6, THE ASSEMBLY COAXIAL WITH THE MAIN SHAFT 23, A COUPLING DISC 13 DRIVES THE MAIN SHAFT 23 DIRECTLY; N2- 1 COUPLING DISCS 14, 15 COMMAND THE SAME SECONDARY SHAFT W2 THROUGH HOLLOW SHAFTS 25, 26 COAXIAL TO THE MAIN SHAFT 23, THE SAID HOLLOW SHAFTS BEING SOLID WITH PINIONS 28, 29, THE SECONDARY SHAFT W2 CAN DRIVE THE MAIN SHAFT THROUGH AT LEAST ONE TORQUE OF SPROCKETS 40, 36 AND 41, 36; A LEVER 44 CONTROLLED BY A PISTON 47 IS PROVIDED IN THE INPUT SHAFT OF THE W2 AND CONTROLS THE DRIVE EITHER OF THE PINION 40 OR OF THE PINION 41. APPLICATIONS TO URBAN BUSES.

Description

The present invention is in the field of transmission devices of

  motor vehicles and more specifically it relates to a gearbox with several "forward" reports intended to equip urban buses in particular. It is known that gearboxes intended for motor coaches circulating mainly in the city are equipped with a hydrodynamic coupler (or converter) and a sun gear that can be controlled automatically or by semiautomatic control without interruption of adhesion. . Tests are underway to find a solution to the poor performance of these gearboxes, by automatic synchronization and clutch. Experienced drivers are still proving that it is still possible to drive a coach equipped with a conventional gearbox by manual control, realizing advantageous acceleration and deceleration values and thus a very low consumption. However, this vigilant behavior demands on the part of the driver a very great concentration which makes him tired.

  prematurely and prevents it from following the traffic better, which can be detrimental.

  The objective of an automatic clutch still remains to achieve speed changes, without accepting the disadvantages of the automatic as we know them: jerk during the clutch / clutch and poor performance. The hydrodynamic elements of this box, the brakes and the clutch rotate inside an oil sump and together with the very bulky pump that is necessary, they are the main causes of poor performance. But if we reduce the friction surface

  lubricated, it always persists a moment of time out.

  The friction clutch on the lubricated face is the essential cause of jerks during

  changes in speed, because the friction plates reveal varying degrees in the oil sump.

  viscosity and adhesion. In addition, the wear of the oil also causes variations in the viscosity and adhesion values. In order to fix these values, it is also necessary to take into account the stopping moments in the use of the friction plates, for this it is necessary to reduce the moments of overlap which are indispensable for smooth driving. On the other hand, it must be taken into account that, in the case of automatic boxes, the friction residues are carried by the oil and may damage bearings, seals and valves. The hydrodynamic elements as well as the friction particles circulating in the oil sump together with a too large oil pump reduce the efficiency of a box.

average of 15%.

  On the other hand, the automatic and synchronized bearing boxes do not have the poor efficiency of the traditional automatic boxes. But they also do not guarantee a smooth driving in the city, because they do not ensure a continuous variation of the engine torque, without interruption of transmission between the engine and the engines. . Then resorting to the engine to synchronize would be contraindicated and would even make things worse (as is the case for heavy duty automatic / semi-automatic gearboxes) - (see Peter KOPF "Synchronization of gearboxes, Automobil Revue

1980, p. 65).

  With regard to the transmission of the speeds of a coach, equipped with a conventional engine, it is possible to achieve the objective set at the beginning: namely

  to obtain a better yield and thereby a decrease in the degree of pollution of the environment and a saving in fuel. All this ensures better comfort using a dry-clutch bearing housing on asbestos-free friction surfaces.

  The single-disc clutch as used in the automobile industry has since

  thirty years of considerable progress and has now reached a degree of reliability that ensures a longevity of dry friction plates that is equal to that of the vehicle. This implies a progressive start, S skating, and a clutch / clutch with each change of the system. Such a clutch system, which only intervenes during shifts, can solve a smooth transmission in the bus line with low investment as well as a minimum wear rate compared to the overall package. hydrodynamic and planetary coupler.

  Then moving from one speed to the other, accelerating, or downshifting becomes possible without jerks thanks to the non-lubricated friction materials, whose data during the movement are substantially identical to those recorded at standstill.

  The very principle of boxes equipped with a set of clutches operating without dry lubricant is already known from German Patent 28 19 124; this method also includes the description of a sun gear operated by brake and interrupted by clutch, allowing a brake start while skating without

  clutch. The object of the invention is to simplify the process of the above gearbox, operated by clutch and to widen its radius of application. In the case of all the known solutions so far, the clutch controls are placed on the front of each of the secondary shafts operating the gear ratio, apart from the em30 clutch control-fixed on the shaft primary school and is in direct contact. It is thus possible to obtain a crankcase diameter of the lower clutch assembly and thereby a lower gear ratio compared to normal transmission gear systems by the use of several gear and secondary shaft torques. who

allow an improved report.

The present invention, which

  to the fixed objective, namely to propose a gearbox allowing smooth shifting and no loss of tension in the transmission chain, and which concerns a gearbox with n gears 5 forward-5 to heavy vehicles including urban buses, said box comprising a main drive shaft which can be controlled, a gear and a planetary group with two bearings directly driven by the main shaft, said planetary group to immobilize a 10 element of the gearing by means of a disk brake which can also be used for starting, said brake rotating in a non-lubricated space and operable by fluid pressure, said speed box further comprising a clutch (K) rotating in the The same space is characterized in that: a) n / 2 coupling disks of an input clutch are arranged, with a set of n / 2 annular pistons in a coupling box driven in continuous rotation by driving means, the assembly being coaxial with the main shaft, b) a coupling disk directly drives the main shaft, c) n / 2 - 1 coupling discs control the same secondary shaft via hollow shafts coaxial with the main shaft, the secondary shaft can drive the main shaft through at least one pair

of pine nuts.

  - As regards a six-speed gearbox, sufficient for driving 30 city buses, this means that the transmission input gear has three pistons and three coupling disks, and that the Main shaft is surrounded by two hollow (secondary) intermediate shafts as well as gear trains. Thus, thanks to these devices, it is possible to avoid (compared to the gearbox bearings, see the patent DE OS 28 19 124) that one or even several secondary trees are provided with commands 2e02294

  transmission. The transmission drives attached to the primary shaft and which are included in an assembly may be of sufficient size that a single disc suffices each time at the speed changes, with a specific wear rate guaranteeing the longevity identical to those of the vehicle.

  With this invention, it is possible at all bearings to open or close the clutch by actuating the non-lubricated friction discs.

  According to another aspect of the invention, provision is made to equip the brake and the clutch with a two-stage sun gear provided with a spring-operated control actuated by compressed air. Thus, the coach is equipped with an automatic locking device which automatically releases when the vehicle is started. Thus in a gearbox in which it is possible to achieve variable control of a planetary group and a clutch, both the brake and the clutch will be provided with a flat spring recuperator compression; in addition and in the case where such a box is provided with an inverter mechanism: a) two pinions are arranged side by side and rotatable on an input shaft of the inverter mechanism, one of the gears meshing directly with a pinion integral in rotation with the main shaft, the other meshing indirectly through a reversing pinion, b) each of said pinions arranged side by side has an internal toothing allowing a free rotation around said shaft input, c)] the input shaft of the inverter mechanism is; shaped as a hollow shaft at least in the region of the two gears arranged side by side and comprises in this zone at least one radially extending slot, and d) in which at least one slot is disposed, is arranged a pivotable lever member , The pivot axis being disposed in the plane adjacent said two gears

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  such that a first lever arm meshes with the internal toothing of the pinion, or a second

  arm meshes with the internal teeth of the other gear.

  Another important aspect of the invention applicable to other models of boxes, is that a control device controlling the pivoting of the lever, is disposed within the input shaft of the inverter mechanism. Advantageously said at least one lever can be pivoted by a spring to be engaged in the internal toothing of a pinion, and by fluid pressure, against the force of the spring, to be engaged in the internal toothing of the other gear. Advantageously, said at least one lever is in the form of a circular sector provided with an external toothing intended to engage in a rack of the control device; advantageously finally, the pivot axis of said at least lever is supported by a spacer disposed between said

two gables side by side.

  The invention will be better understood and details thereof will be apparent from the description which

  will be made of a particular embodiment in connection with the figures of the plates appended in] esquelles: - Fig.1 illustrates in longitudinal section a speed boot of the invention, and

  - Fig.2 is a partial cross section along a plane A of the previous figure.

- The gearbox represented

  In the figures is a 6-speed, six-speed, air-controlled, automatic bus-controlled bus, one of which is "overdrive".

  In FIG. 1, it will be apparent that the speed boot of the invention comprises a main casing G supporting a flange D, an outlet casing A supported by an intermediate flange L, an input coupling assembly E, secondary shafts W1 and W2, a planetary group P, a brake B and a clutch K; tree of

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  transmission engages with the motor attached to a bell-shaped portion 1 of the main housing, transmits the movement to the box by a flange 2 flange. To this end, the flange 2 is welded to a tubular part 3 provided internally with longitudinal grooves 4 in which pairs of balls 5 which are supported on a ring 6 are arranged, which ensures a connection between the motor and the coupling. entrance E; these pairs of balls are held by conical annular springs 7 on a coupling housing which is composed of a support plate 9 assembled by screw 8 to a starting plate 10, to an intermediate plate 11 and finally to a plate of 12. With this arrangement the jolts coming from the motor or the box are elastically damped by the fact that the 15 pairs of balls 5 comprise the springs 7 by leaning

on crosses of the ring 6.

  The input coupling E is provided with three discs 13, 14, 15 which can be connected to the motor by annular pistons 16, 17, 18 actuated by compressed air, sealed to their inside and outside diameter and by pads 19, 20 , 21 movable in the axial direction. The disc 13 is connected by its hub 22 to the primary shaft 23, the disc 14 is connected by its hub 24 to the secondary shaft

  and the disc 15 is connected to the shaft 26.

  All of the following are made in one piece: the main shaft 23 with a sun gear 27 of the sun gear, the hollow shaft 26 with a pinion 29. The hollow shafts 25 and 26 are held by needle bearings 30 , 31 on the main drive shaft. Thrust bearings 32, 33 ensure the axial retention of the two hollow shafts 25 and 26 sliding between them and the retention of the hollow shaft 25 with respect to the main transmission shaft 23. The sum of the radial and axial forces is received The main shaft 23, made in one piece with the sun gear central gear, supports, next to the two hollow shafts 25 and 26 including the pinions 28 and 29, a pulley of

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  outlet 36 by means of a toothing.

  The secondary shaft W2 has a pinion 37 meshing with the pinion 28, extending by means of a cylindrical gear-to which the shaft is supported by a bearing with 5 cones 38, and which supports a pinion 39 meshing with a driving pinion 29. It has on the output side of the transmission a hollow cylinder, provided in several places with radial slots, around which are arranged gears 40 and 41 with external and internal gears. The pinion 40 10 is in direct contact with the pinion 36 in which it meshes; the pinion 41 meshes with an inverter pinion 42 of the or of the reverse gears. The hollow cylinder in extension of the pinion 37 in which are milled slits 108, is supported by means of a conical bearing 43 by a flange D which closes the housing G. In the slots 108 are housed pivotable toothed sectors 44 cut by stamping, - as well as pivots for the sectors, rel. The toothed sectors 44 mesh with their external toothing in circular ribs of a cylindrical rack 46 extending a piston 47 biased by a spring 48 (FIG. 1). in an end position in which the sectors 44 mesh with the internal toothing of the pinion 40 to couple it with the secondary shaft W2. In general, it can be said that each toothed sector 44 is in principle a lever which in an end position (FIG. 1) does not engage one of its arms (441) in the internal toothing of the

pinion 40.

  By passing the reverse, the compressed air arrives by a magnetic valve in lines 49 of a cover 50 and is conveyed by the tube 51 in the foutrre'au of the piston 47. Thus the lever arms 441 (d Other tarnished edges of the toothed sectors 44) come out of the internal toothing of the pinion 41. The pinion 40 is

  released, and the pinion 41 is connected to the secondary shaft W2.

The flange D which supports the

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  Bearing 43 of the secondary shaft engages in a cylindrical recess 52 the main shaft 23 and distributes the pressure which actuates] the control of the four couplings. Thus is shown in sectional view the conduit 53 of the flange D 5 through which the pressure is conveyed, coming from a proportional valve 55 actuated by a magnetic control 54, the pressure passing through a radial duct 56 of the shaft 23 by means of a distributor 57 to the gear ratio concerned. On this distributor, inserted into a bore of the shaft 23 are welded three tubes placed between

  them in a concentric manner and leading to the front to the shot coup] ages and another tube leading to the output clutch K. The tubes leading to the front are referenced 58,59,60, the tube leading to the outlet 15 is referenced 61.

  The compressed air from the distributor is conveyed to the chambers of the pistons 16, 17, 18 through three radial ducts formed in the support plate 9 elastically connected to the engine, the lines passing from an inner projection 100 of the plate -support centered in the main shaft by a needle bearing 101; the pressure chamber of the annular piston 17 is supplied by the radial duct 102 and then by the longitudinal duct 103 and a cased passage 104, and finally by the radial duct 105; the pressure chamber of the piston 18 is fed by the radial duct 106 (shown partially) and the pressure chamber of the

  piston 16 through line 107 (shown at the beginning).

  The transmission of the planetary movement P equipped with the brake B and the clutch K is

  the pinion 27 of the main shaft, which is mounted on a conical bearing 35 supported by a sleeve 67 clutch.

  The pinion 27 drives, by the planetary gears 62 which engage in a hollow ring 63, a shaft 64 said bridging, when the brake circuit B is closed and that of the clutch open. This bridge shaft 64 screwed to a plate 66, supports the planet gears 62 placed on

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  bolts 65 by ball bearings 68. When the brake circuit B is open and the clutch K closed, the sun gear P rotates en-bloc and the reaction phenomenon passes through the bridge shaft, a box 86 and by a The crown is connected to a flange 70 by a crown support 69, above the bridge shaft, and by the flange to the clutch K. The bridge shaft 64 is supported by two roller bearings 72,73 resting inside the crown support 69. Stop 74,75 transmit the efforts

  axial axes of the main shaft 23 and the partition shaft 64.

  The flange 70 and the crown support 69 together bear on two conical bearings 76 'and 77 supported by an extension of the intermediate flange L.15 Inside the cylindrical space 78 formed between the intermediate flange L and the housing of output A is mounted a stepped piston 82 controlled by flat springs 79. This piston is axially movable. On this piston are supported flat springs 79 closing the brake circuit, this device is composed of pads with Sinter packing 80, which bear in the output casing A, as well as brake discs 81 brake B

rotating with the collar 70.

  By the pressure inlet inside the sleeve 83 of the annular piston 81 which bears axially on one of the housings of the box A, the brake is released by the tension of the flat springs 79, or else it is maintained in a latent state during start-up by a pressure device. Like the brake B, the clutch K 30 is kept closed, in the absence of pressure, thanks to the springs. The clutch K is composed of a support 86, on which the steel slats 85 rest, and it is. connected by Frontal toothing to the bridge shaft 35 64, as well as trim strips 87 which are suspended from the flange 70. The clutch is closed by means of a flat spring.S which bears on the outlet cup 71

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  11i and which presses against an outlet steel strip 89. The spring 88 is tensioned by the pressure conveyed by a tube 61 and controls, in an axial manner, a movable piston 9 in a cylinder 90 of the housing 86 ; the tensioned spring 88 releases the assembly of the clutch consisting of lining strips 87 and steel strips 85. The flat spring 88 has levers 92 facing inwards, levers which are clamped in housings of the cup 71 under which the levers are screwed by screw 93 to the clutch support 86. A cardan flange which ensures the transmission of the deceleration phenomenon to the axis is fixed by

rod screws 94.

  The ordinary oil lubrication of the gearbox is effected by an oil pump driven by the reversing pinion 42. This pump is installed under the cast iron flange D. The oil is partly conveyed by cylindrical recess 52 from the flange D passing through the slot 95 and the radial duct 96 in the circular space outside the tube 60 and by the radial perforations in the shaft 23, it is used to lubricate the bearings. Furthermore, the pump injects oil which passes through the pipe 97 into the cover 50, a pipe 98 to the notches of the secondary shaft W2 o are placed the toothed sectors 44 of the rear step. From there, the lubrication of the gears takes place. The sun gear is lubricated thanks to a driving

longitudinal 99 in the shaft 23.

  The operation of this gearbox is indicated in the box below. The individual controls of the input clutch E are marked

  by E1 (disk 13), E2 (disk 14) and E3 (disk 15).

  Sprocket with Clutch Bearing Number of Multiplier Ratio and Brake Select. teeth engaged

1 28-37-40-36-27-62-63 E2 B 4 (*)

2 27 - 62 - 63 EB 2

E1B

3 29-39-40-36-27-62-63 E3 B 4

4 28-37-40-36 E2 K 2

El0 - E

_ E10

6 29-39-40-36 E3 K 2

(Sunultipliée)

R 28-37-41-42-36-27-62-63 E2 B 5

  E2B (*) planetary group; double tooth gear

  A bus, or other urban bus, equipped with a gearbox described here is provided with an accelerator pedal and a brake pedal. The start-up and gearshifting processes are performed by a microprocessor whose program can be manually modified, provided that a manual intervention of the driver is provided during a mountain tour, whether empty or complete. The driver must be given the ability to intervene in the automatic programming in order, for example, to prevent a shift to a higher / lower speed.

  The advantage of the vehicle locking device, a device that is both simple and reliable, which makes it possible to block the vehicle by a wide radius brake 15 having maximum reliability, can be further exploited, by the fact that the driver, thanks to a small control lever; may control additional braking; for example during a restart after stop, it is possible to perform a blockage without involving the brakes of the 20 wheels. During a stop in a climb, the driver can block the vehicle and then use the brakes to

to restart. -

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  Although it has been described a particular embodiment of a gearbox according to the invention, it should be understood that the scope of the latter is not limited to this form but that it extends to any gearbox containing the general or particular characteristics, stated more

  top taken separately or in combination.

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R E V E ND I C A T I ONS

  1. Gearbox with n forward gears for heavy vehicles, in particular for urban buses, said gearbox comprising a main drive shaft which can be driven, a gear and a two-stage planetary gear set directly driven by main shaft, said planetary group for immobilizing an element of the gear by means of a disk brake (B) can also be used for starting, said rotating brake. in a non-lubricated space which can be actuated by fluid pressure, said gearbox further comprising a clutch (K) rotating in the same space, characterized in that: a) n / 2 coupling disks ( 13,14,15) of an input clutch (E) are arranged, with an assembly of n / 2 annular control piston (16,17,15), in a coupling housing (9,12) driven in continuous rotation by driving members (2,6), the assembly being coaxial with the main shaft (23), b) a coupling disc (13) directly drives the main shaft (23), c) n / 2 - 1 coupling discs (14,15) control the same secondary shaft (W2) via hollow shafts (25,26) coaxial with the main shaft (23), said hollow shafts being secured of gears (28,29), the secondary shaft (W2) being able to drive the main shaft through at least one pair of gears (40,36 and 41,36); 2. Gearbox according to claim 1, wherein it is possible to achieve variable control of a sun gear P and the clutch K, characterized by the fact that both the

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  brake (B) and clutch (K) are provided with a compression spring (79,88);

  3. Gearbox according to any one of claims 1 and 2, further provided with an inverter mechanism, o

  characterized in that: a) two pinions (40,41) are arranged side by side and rotatably movable on an input shaft (W2) of the inverter mechanism, one (41) of the gears meshing directly with a pinion (36) integral in rotation with the main shaft (23), the other meshing indirectly through an inverter pinion (46), b) each of said gears (40,41) arranged side by side 15 has an internal toothing allowing a free rotation about said input shaft (W2), c) the input shaft (W2) of the inverter mechanism is shaped hollow shaft at least in the area of the two gears arranged side to 40,41) and comprises in this area at least one radially extending slot (108), and that in said at least one slot there is a pivotable lever member (44), pivot axis being disposed in the plane adjacent said two gears 25 side by side (40,41) so that is a first bra s (441) of the lever engages in the internal toothing of the pinion (40), or a second arm (442) meshes with the internal toothing of the other pinion (41); 4. Gearbox according to claim 3, characterized by:

  in that a control device (47) controlling the pivoting of the lever (44) is.

  disposed within the input shaft (W2) of the inverter mechanism;

  5. Gearbox according to claims 3 and 4,

  characterized in that said at least one lever (44) can be pivoted by a spring (48) to be latched in the internal toothing of a pinion (40), and by a fluid pressure against the spring force, to be engaged in the internal toothing of the other pinion (41);

  6. Gearbox according to claims 4 and 5,

  characterized in that said at least one lever (44) is shaped as a circular sector provided with an external toothing for meshing in a rack (46) of the control device (47); 7.- vitess.e box according to any one of claims 3 to 6,

characterized:

  in that the pivot axis of said at least one lever (44) is supported by a spacer (45) disposed between said two side-by-side gears (40,41).