WO2012155877A1

WO2012155877A1 - Power-take-off clutch arrangement for tractors

Info

Publication number: WO2012155877A1
Application number: PCT/DE2012/000443
Authority: WO
Inventors: Matthias Vogt; Patrick Weydmann; Gerhard Gander; Alexander OBITZ; Vladimir MERK
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2011-05-16
Filing date: 2012-05-02
Publication date: 2012-11-22
Also published as: DE102012207244A1

Abstract

The invention relates to a clutch arrangement (1) for use in the drive train of a tractor, said arrangement comprising a drive clutch (2) and a power-take-off clutch (3). The drive clutch is located between an internal combustion engine and an input transmission shaft and the power-take-off clutch is located between the internal combustion engine and a power-take-off. The clutch arrangement comprises a clutch housing (6) with a formed sheet-metal part.

Description

Coupling arrangement for tractors with PTO

The invention relates to a clutch assembly for use in the drive train of a tractor comprising a drive clutch and a PTO clutch, wherein the drive clutch between an engine and a transmission input shaft and the PTO clutch between the engine and a PTO are arranged.

Tractors and these comparable tools such as construction equipment and the like often have double clutches in their drive train. The powertrain includes a main driveline and a sub-driveline. The first is used to drive the vehicle, second to the drive of work machines, usually via a PTO. A clutch is used for torque transmission between the engine and transmission in the main drivetrain, the other coupling torque transmission between the engine and PTO in the PTO. The power take-off is also referred to as power take-off (PTO), according to which this power take-off associated clutch as PTO clutch or PTO clutch and arranged the main driveline clutch is referred to as a drive clutch.

Tractor double clutches known in the art include a cast housing as a clutch housing. Accordingly, the couplings are very heavy and the cast housing must be machined, as only so the required accuracy can be achieved. The machining is complex and expensive compared to sheet metal working. A disadvantage of couplings according to the prior art is the relatively large casting mass and a comparatively low bursting speed. Another disadvantage is that extensive machining operations are necessary during production. A coupling according to the prior art also includes many different items. Another disadvantage is that much of the assembly of the coupling must be done manually.

An object of the present invention is therefore to at least partially circumvent the aforementioned disadvantages.

Bestätigungskopiel This object is achieved by a clutch assembly for use in the drive train of a tractor comprising a drive clutch and a PTO clutch, wherein the drive clutch between an internal combustion engine and a transmission input shaft and the PTO clutch between the engine and a PTO are arranged, wherein the clutch assembly comprises a clutch housing having a Sheet metal forming part includes.

By using a Blechumformteils as a clutch housing much of the machining in couplings according to the prior art over the inventive solution falls away. In addition, the inventive solution has a significant weight advantage over prior art solutions. Another advantage is that it is easier to integrate a self-adjustment in the clutch assembly according to the invention.

In one embodiment of the invention, the drive clutch and the auxiliary drive clutch each comprise an axially displaceable pressure plate and an axially fixed counter-pressure plate, between each of which a clutch disc can be clamped. In the coupling arrangement according to the invention, it is preferably provided that the pressure direction of both pressure plates of the individual clutches, ie the drive clutch and the auxiliary drive clutch, have the same direction of action or pressure direction. For this purpose, in one embodiment of the invention, it is provided that the counter-pressure plate of the drive clutch is not at the same time a coupling component of the auxiliary drive clutch.

The clutch housing is fixedly connected in one embodiment of the invention with a flywheel, wherein the flywheel counter-pressure plate of the PTO clutch is. It is unlike in known double clutches no medium pressure plate, the counter-pressure plate of both clutches is used, but each individual counter-pressure plates for the respective partial clutches. The counter-pressure plate of the power take-off clutch is in one embodiment of the invention, the flywheel of the clutch assembly. The flywheel of the clutch assembly is firmly connected to the reaction plate of the drive clutch.

The counter-pressure plate of the drive clutch in one embodiment of the invention comprises a plate-shaped portion which cooperates with the pressure plate, and a wood-cylindrical portion which is connected to the flywheel. The counter-pressure plate of the driving Coupling forms a housing part for the PTO clutch. This housing part is preferably made as a casting.

The auxiliary drive clutch comprises in one embodiment of the invention, a pressure plate which is mounted axially movable and can be actuated by means of at least one pressure anchor by a disc spring. The pressure anchor is the transmission element between disc spring and pressure plate. The pressure plate is pressed, for example, by leaf springs, which simultaneously serve for torque transmission between the pressure plate and the counter-pressure plate in the open position.

The counter-pressure plate has in one embodiment of the invention openings for receiving the pressure anchor. The breakthroughs are designed to be a match between the pressure anchor and the counterpressure plate.

The plate spring of the power take-off clutch is arranged in an embodiment of the invention on the side facing away from the flywheel of the clutch housing. The disc springs of both clutches are arranged on both sides of the coupling housing, so that the available space is used optimally.

The PTO clutch is an actively applied clutch (safety PTO) or an actively pressed clutch.

The object mentioned at the outset is also achieved by the use of a double clutch with a clutch housing which comprises a sheet metal forming part in the drive train of a tractor for torque transmission between a drive motor and a transmission input shaft and for torque transmission between the internal combustion engine and a power take-off.

In the following, embodiments of the invention with reference to the accompanying

Drawings explained. Showing:

Figure 1 shows a first embodiment of a coupling arrangement according to the invention as

Schematic diagram; Figure 2 shows a second embodiment of a coupling arrangement according to the invention as a schematic diagram;

Figure 3 shows an embodiment according to the schematic diagram of Figure 1 in a spatial

Presentation;

Figure 4 shows the coupling arrangement of Figure 4 with disassembled plate spring for

PTO clutch;

FIG. 5 shows the pressure anchor in a single representation;

Figure 6 shows the coupling arrangement of Figure 6 with disassembled plate spring for

PTO clutch;

FIG. 7 shows the pressure anchor in a single representation;

8 shows the pressure plate of the auxiliary drive clutch in a single representation.

Figure 1 shows a first embodiment of a coupling assembly 1 according to the invention in a schematic representation. The clutch assembly 1 includes a drive clutch 2 and a PTO clutch 3. Both the drive clutch 2 and the PTO clutch 3 are the drive side connected to a not shown in Figure 1 crankshaft of an internal combustion engine. The crankshaft of the internal combustion engine is for this purpose connected to a flywheel 4 shown only schematically in FIG. The flywheel 4 is at the same time the counter-pressure plate of the auxiliary drive clutch 3, therefore, of the flywheel 4 in Figure 1, only the area which cooperates with the clutch disc of the auxiliary drive clutch 3 shown later, shown.

With the flywheel 4, a counter-pressure plate 5 of the clutch 2 is firmly connected. The connection can be made for example in the form of a screw or the like. Just as firmly with the counter-pressure plate 5 of the clutch and the flywheel 4, a clutch housing 6 is connected, for example screwed. The auxiliary drive coupling 3 comprises a pressure plate 7 which is mounted so as to be displaceable in the axial direction with respect to the counterpressure plate 4 or the flywheel which carries the counterpressure plate 4. The axial direction is the direction predetermined by the rotation axis R. The entire coupling The arrangement 1 rotates in operation about the axis of rotation R, which is simultaneously the axis of rotation of the crankshaft and the input shafts, not shown here, of a manual transmission or the auxiliary drive, not shown. Between the pressure plate 7 and the counter-pressure plate 4, a clutch disc 8 can be clamped in a conventional manner and thereby acted upon with a torque. The clutch disc 8 includes in a conventional manner clutch linings 9, which is disposed on both sides of a disc 10 which is connected to a hub 11 which is connected, for example, a spline 12 with an input shaft of a side drive, not shown. The pressure plate 7 of the PTO clutch 3 is connected, for example, with leaf springs, not shown, with the flywheel 4 and the counter-pressure plate 5, so that the pressure plate 7 is displaceable in the axial direction against the force of the springs, but can transmit a torque. A plurality of pressure anchors 13, of which only one is shown in FIG. 1, are in contact with the radially outer region of a plate spring 15 with an annular connection region 14. The plate spring 15 is connected to the coupling housing 6 by means of rivets 16. Wire rings 17 are placed radially on both sides of the plate spring 15 around the rivets 6 around and define the Stülpmittelpunkt S of the plate spring 15. If a radially inner contact portion 18 of the plate spring 15 is pressed in the direction of arrow 19, there is a movement of the radially outer portion of the plate spring 15 in the opposite direction, so that the pressure armature 13 moves in the direction opposite to the arrow 19 and the distance of the pressure plate 7 is increased by the counter-pressure plate 4, so that the PTO clutch 3 is opened. The pressure anchor 13 protrude into grooves of the pressure plate 7 and are screwed thereto, so that the pressure anchor 7 are fixed in the circumferential direction.

The drive clutch 2 comprises, in addition to the counter-pressure plate 5 of the drive clutch

Pressure plate 20 which is displaceable with leaf springs in the axial direction relative to the counter-pressure plate 5, but this is mounted with respect to torsionally rigid in the circumferential direction. A disk spring 21 is in contact with the pressure plate 20 with its radially outer region. The disk spring 21 is mounted on the clutch housing 6 by means of rivets 22 and wire rings 23, similar to the case of the first disk spring 15. Here too, the wire rings 23 form the cusp center S2 of the plate spring 21. If a radially outer region ^" 24 is pressed in the direction of the arrow 25, the radially outer region of the plate spring 21 moves in the opposite direction, so that the pressure plate 20 is relieved and the distance between the pressure plate 20 and counter-pressure plate 5 is increased and the drive clutch 2 is opened.

Between the pressure plate 20 and the counter-pressure plate 5 of the clutch 2 is a

Clutch disc 26 is arranged, which comprises a plate 27, which on both sides with friction 28 is provided and which is connected to a secondary flange 29 of a damper 30. The damper 30 comprises, in addition to the secondary flange 29, a primary flange 31. Between the secondary flange 29 and the primary flange 31, a bow spring arrangement 32 is clamped in a manner known per se so that a relative rotation of the secondary flange 29 with respect to the primary flange 31 is possible. The primary flange 31 is in turn connected to a hub 33, which is connected by means of a spline with a hollow shaft which is arranged coaxially to the drive shaft of the auxiliary drive.

The plate spring 15 of the power take-off clutch is arranged on the side facing away from the flywheel 4 of the clutch housing 6. The plate spring 21 of the drive clutch 2 is arranged on the flywheel 4 facing side of the clutch housing 6. The clutch housing 6 comprises a mounting flange 34, with which the clutch housing 6 is screwed to the counter-pressure plate 5 and the flywheel 4, a substantially in section in the axial direction extending housing part 35 and a substantially radially extending housing part 36, on which the disc springs 15 and 21 are fastened by means of rivets 16 and 22. For this purpose, the essentially radially extending region 36 comprises two regions 36a and 36b arranged offset from one another in the axial direction, wherein the region 36a, which serves to receive the plate spring 15 for the auxiliary drive coupling, is arranged axially further outward, that is to say away from the flywheel 4 as the radially further inwardly disposed portion 36 b, which serves to receive the plate spring 21 for the clutch 2. The clutch assembly 1 thus comprises a superstructure, which essentially contains the elements of the drive clutch, and a substructure, which essentially contains the elements of the auxiliary drive clutch.

The exemplary embodiment of FIG. 1 comprises an actively pressed driving clutch and an actively pressed auxiliary drive clutch. 2 shows an embodiment is shown in which the drive clutch 2 is actively pressed and the PTO clutch 3 is actively pressed (so-called safety PTO). The essential difference from the embodiment of Figure 1 is that the contact point or in a spatial representation of the contact ring between the pressure armature 13 and the plate spring 15 is not as in the embodiment of Figure 1 radially outside of the defined by rivets 16 and wire rings 17 Stülpkreises S, but radially within the Stülpkreises S is located. However, the plate spring 15 generates no engagement force, this is effected by actively pressing the plate spring 15 in the manner of a lever spring. In this respect, diaphragm spring is used here synonymous with lever spring in the actively compressed PTO clutch. If the diaphragm spring 15 is moved in the direction of the arrow 19, the pressure armature 13 and thus the pressure plate 7 move in the same direction. direction, so it is an actively pressed clutch. In Figure 2, screws 54 are also shown for screwing the counter-pressure plate 5 of the clutch 2 with the counter-pressure plate 4 of the auxiliary drive clutch 2 and the flywheel of the clutch assembly. With the screws 54 and the clutch housing 6 with the counter-pressure plates 4, 5 is screwed.

Figure 3 shows an embodiment according to the schematic diagram of Figure 1 in a three-dimensional representation. To recognize the counter pressure plate 5 of the clutch 2, with the

Flywheel 4 is screwed. Furthermore, the coupling housing 6 can be seen, which is screwed by means of screws 37 with the counter-pressure plate 5. Tabs 38 of the pressure anchor 13 protrude through openings 39 of the coupling housing 6. The openings 39 are larger than the cross-sectional area of the tie rods 13, so that both have play with each other. A leaf spring 40a is connected to the clutch housing 6 with rivets 41a and to the pressure plate 7 of the auxiliary drive clutch 3 with rivets 42a. Several of the leaf springs 40a are distributed over the circumference and serve for torque transmission between the pressure plate and the counter-pressure plate. In Figure 3 is also seen the plate spring 15 for the PTO clutch, which is connected to a plurality of rivets 16 to the clutch housing 6. Also visible is the wire ring 17 facing away from the clutch housing 6. Furthermore, the disk spring 21 can be seen for the drive clutch.

FIG. 4 shows the coupling arrangement 1 according to FIG. 4 with the plate spring 15 removed for the auxiliary drive coupling 3. As a result, a larger part of the pressure anchor 13 is visible. A leaf spring 40b is connected with rivets 41b to the clutch housing 6 and with rivets 42b to the pressure plate 20 of the clutch 2. Several of the leaf springs 40b are arranged distributed over the circumference and serve for torque transmission between the pressure plate 20 and the counter-pressure plate 5.

FIG. 5 shows the pressure anchor 13 in a single representation. The pressure anchor 13 comprises an annular or hollow cylindrical base body 43, which in the installation position of the flywheel 4 facing away from the area is radially inwardly folded and forms a Anlagebund 44 for the plate spring 15. From the base body 43, a plurality of tabs 45 extend in the installed position in the direction of the flywheel 4. The tabs 45 are with their head-side ends 46 in contact with the pressure plate 7 of the PTO clutch and are screwed to it. For this purpose, the pressure plate 7, as can be seen from Figure 8, flanges 50 extending in the circumferential direction grooves 51 into which the tabs 45 protrude in the installed position. In itself bores 53 are bored axially from the pressure plate 7 elevating bores 53, into which screws, not shown, for screwing the tabs 45 to the pressure plate 7 are screwed. Not all bore flanges 52 must be provided with holes 53. The pressure plate 7 according to Figure 8 can be used for both embodiments shown here.

Figure 6 and Figure 7 show illustrations comparable to Figures 4 and 5 for a

Embodiment of a clutch assembly, as shown in a schematic diagram in Figure 2, ie for a clutch assembly with an actively pressed PTO clutch 3. When mounted plate spring 15, the clutch is practically not externally distinguishable from the embodiment of Figure 3, therefore, was on a re-presentation of the embodiment omitted in a fully assembled arrangement. As can be seen from Figure 7, extends a plate-shaped part 47 of the pressure armature 13, this is also denoted in the schematic diagram of Figure 2 by the reference numeral 47, of the main body 43 radially inward and covers the hole circle for the rivets 16. For the rivets 16 are, as can be seen in Figure 6, now 48 holes introduced into the plate-shaped part 47 of the pressure armature 13. Through the holes 47, the rivets 16 are passed and riveted to the coupling housing 6. It can be dispensed with the arranged on the coupling housing 6 side of the plate spring 15 arranged wire ring 17.

Radially within the circle defined by the rivets 16, at the outer edge of the Stülpkreis is for the plate spring 15, an annular edge 49 is arranged, this is also shown in Figure 2, which is in contact with the disc spring 15, not shown in Figure 7. If the plate spring 15 is pressed in the illustration of Figure 2 with its contact area 18 in the direction of the flywheel 4, this is shown in Figure 2 and in Figure 1 by the arrow 19, the annular edge 49 and thus the pressure armature 13 is also in Direction of the arrow 19 pressed. The auxiliary drive clutch is thus closed when the contact area 18 is pressed in the direction of the arrow 19. The plate spring 15 is therefore designed so that the auxiliary drive clutch is opened when not acted on the contact portion 18 plate spring 15 for the PTO clutch.

FIG. 7 shows the pressure anchor 13 of the exemplary embodiment of FIG. 6 in a single representation. The difference to the pressure anchor in the embodiment of Figures 4 and 5 is merely the embodiment of the plate-shaped part 47 of the pressure armature 13 in the embodiment of Figures 6 and 7 relative to the Anlagebund 44 in the embodiment of the figures 4 and 5. By separating the dish-shaped part 47 in the pressure anchor of the embodiment of Figures 6 and 7, the pressure anchor 13 for the embodiment of Figures 4 and 5 is obtained. The essential parts of both embodiments, ie the embodiments of Figures 4 and 5, which follow the schematic diagram of Figure 1, and the embodiment of Figures 6 and 7, which follows the schematic diagram of Figure 2 are therefore either the same or can be easily converted into each other ,

In particular, the pressure anchor 13 can be rebuilt as previously shown by twisting or separating the dish-shaped part 47 of the pressure armature 13 used in the embodiment of Figures 6 and 7 to the pressure armature 13 used in the embodiment of Figures 4 and 5. The two embodiments differ in addition to the pressure armature 13 only by the plate spring 15 for the PTO clutch 3 and the length of the bolt 16. If necessary, it is also possible in the embodiment of Figures 6 and 7, the same disc spring as in the embodiment of Figures 4 and 5 whose spring characteristic would then not be optimized for the clutch used.

Reference List Coupling arrangement

clutch

PTO clutch

Flywheel (at the same time pressure plate PTO clutch) Counter-pressure plate of the drive clutch

clutch housing

Pressure plate of the PTO clutch

clutch disc

clutch lining

disc

hub

splines

pressure anchor

connecting area

Disc spring for PTO clutch

rivet

wire ring

contact area

arrow

Pressure plate of the drive clutch

Disc spring for driving clutch

rivet

wire ring

outer area

arrow

clutch disc

plate

friction lining

Sekundärflansch

damper

primary flange

Arch spring assembly hub

Mounting flange housing part

radially extending region

b staggered areas screw

flap

opening

leaf spring

rivet

body

contact collar

tabs

head end

plate-shaped part of the pressure anchor

drilling

annular edge

flange

groove

Bohrungsflansch

drilling

screw

Claims

claims

A clutch assembly (1) for use in the driveline of a tractor comprising a drive clutch (2) and a power take-off clutch (3), wherein the drive clutch (2) is disposed between an engine and a transmission input shaft and the power take-off clutch (3) between the engine and a power take-off are, characterized in that the coupling arrangement (1) comprises a coupling housing (6) comprising a sheet metal forming part.

2. Coupling arrangement according to claim 1, characterized in that the drive clutch (2) and the auxiliary drive clutch (3) each comprise an axially displaceable pressure plate (7, 20) and an axially fixed counter-pressure plate (4, 5), between each of which a clutch disc can be clamped is.

3. Coupling arrangement according to claim 2, characterized in that the coupling housing is fixedly connected to a flywheel (4), wherein the flywheel (4) counter-pressure plate of the auxiliary drive coupling (3).

4. Coupling arrangement according to one of the preceding claims, characterized in that the counter-pressure plate (5) of the drive clutch (2) has a plate-shaped portion which cooperates with the pressure plate (20), and a wood cylindrical portion which is connected to the flywheel (4) , includes.

5. Coupling arrangement according to one of the preceding claims, characterized in that the auxiliary drive clutch comprises a pressure plate which is mounted axially movable and by means of at least one pressure armature by a diaphragm spring is actuated.

6. Coupling arrangement according to claim 5, characterized in that the counter-pressure plate (5) has openings (39) for receiving the pressure armature (13).

7. Coupling arrangement according to claim 5 or 6, characterized in that the plate spring of the auxiliary drive coupling (3) on the flywheel (4) facing away from the coupling housing (6) is arranged.

8. Coupling arrangement according to one of the preceding claims, characterized in that the auxiliary drive coupling (3) is an actively pressed-coupling.

9. Coupling arrangement according to one of the preceding claims, characterized in that the auxiliary drive coupling (3) is an actively impressed coupling.

10. Use of a dual clutch with a clutch housing (6) comprising a sheet metal forming part, in the drive train of a tractor for torque transmission between a drive motor and a transmission input shaft and for torque transmission between the engine and a PTO.