JPS6128853B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The invention provides an adjusting piston which is connected to an adjusting member of a transmission and which is loaded by pressure from both sides, and which controls the pressure in both pressure chambers in front of both end faces of the adjusting piston. Regulating device for a hydrodynamic transmission, comprising a control valve and a control pressure measuring piston, which is disposed slidably in the casing and is loaded by the working pressure of the transmission. a pressure-measuring piston rests on the lever, the lever being hinged at one end to the adjusting piston and supported on the adjusting piston via an elastic support member; Relating to a type configured to operate a control valve. In the case of known control devices of this type, a control valve actuated by a lever is arranged in the housing of the regulating device (DE-A-2003-774). The distance between the point at which the actuating member of the control valve abuts the lever and the pivot point of the lever is changed during sliding of the regulating piston, and so that the stroke and the sensitive response of the control valve are also dependent on the position of the regulating piston. The result will be changed. Furthermore, in the case of such a device of lever and/or control valve, it must be adjusted such that in the neutral position of the control valve, the contact edge of the lever lies precisely parallel to the direction of movement of the adjusting piston. Furthermore, relatively high costs are required to manufacture the connecting passage for the control valve in the housing.

SUMMARY OF THE INVENTION The object of the invention is to provide an adjustment device that is inexpensive to manufacture and works uniformly and efficiently in each position of the adjustment piston.

In order to solve this problem, the present invention provides that the control valve provided on the regulating piston is arranged at right angles to the longitudinal axis of the regulating piston. In this case, the force associated with the pressure produced by the control pressure-measuring piston is determined by the distance from the pivot axis of the lever that is proportional to the displacement volume of the pump or hydraulic transmission machine regulated by the regulating piston. acts on the lever. Such a device has the advantage that when the adjusting piston assumes a position corresponding to the zero position of the hydraulic piston pump or transmission device regulated by the adjusting piston, the pivot axis of the lever is aligned with the control pressure measuring piston. is on the line of action of the force exerted on the lever by The elastic supporting member of the lever, which is designed, for example, as a spring, must introduce a constant counter-torque into the lever that is proportional to the power transmitted by the transmission or the power received by the pump. It is known that the control valve itself is arranged on the regulating piston. Furthermore, according to another embodiment of the invention, the regulator can be operated in relation to the delivery pressures in the plurality of hydraulic circulations, for example the delivery outputs of the plurality of hydraulic pumps, so that the overall output regulation is can get. In this case, each pump is equipped with the same regulator and is regulated automatically and simultaneously, and in each case in relation to the entire output range of the different pumps, so that the pumps are always regulated together. Accepts constant output.

In addition to providing a spring as an elastic support for the lever, a pressure-loaded piston is also provided, the pressure being varied in relation to the piston position and thereby providing support. The corresponding properties are obtained. At the same time, however, remote control is possible, in which the pressure is varied externally. Particularly advantageously, a spring can be combined in a supported manner on a pressure-loaded piston, so that a spring characteristic is achieved by means of the spring and a remote control is achieved by means of the piston.

If the elastic support element is formed by a spring, this support element can also be adjustable or can be provided with a plurality of springs connected parallel to one another, which springs can be adjusted individually. be. A plurality of springs connected in parallel has the advantage that in some cases a plurality of springs can be advantageously mounted on the adjusting piston.

According to an advantageous embodiment, the device according to the invention can be combined with a pressure interrupter, in which case the load on the regulating piston is reduced to zero when a predetermined limit pressure is reached.
The chamber in front of the end face of the adjusting piston, which moves in the direction of the stroke position, is loaded in such a way that the adjusting piston moves to the zero stroke position. In the case of differential pistons, the pressure chamber is large. However, in this case the control valve is also correspondingly influenced by the pressure breaker, so that the pressure introduced into the pressure chamber via the pressure breaker limit pressure valve immediately flows out again via the control valve. Consideration must be given to ensure that this is not the case.

The invention will be explained below with reference to the exemplary embodiments shown.

A bore is formed in the housing part 1 as a large diameter cylinder 2, which cylinder is coaxial with a small diameter cylinder 3 in the housing part 4. Both casing parts 1, 4 are part of a common overall casing, which is no longer shown in the drawing. A further bore is formed in the housing part 1 and forms a cylinder 5 in which a control pressure measuring piston 6 can slide.

An adjusting piston 7 is slidable in the cylinders 2, 3, which is guided in a sealed manner in the cylinder 3, which is formed by a bore in the right-hand part in the drawing, and , the left-hand region has a piston plate 8;
The piston plate is guided in a sealed manner in a cylinder 2 formed by a bore. An adjusting piston 7 is fixedly connected to an adjusting lever 9, which itself is connected to an adjusting element of an adjustable piston pump (not shown). In particular, the adjusting lever 9 engages via a spherical head on a swivel slide of a swivel-slider variable delivery pump.

A passage 10 is provided in the casing parts 1, 4, which opens into the cylinder 3 on one side and into the cylinder 5 on the other side,
and is connected via a passage 11 to the discharge conduit of the pump. The housing interior, in which the adjusting lever 9 is moved, is connected to a pressure-free outlet into the container.

The adjusting piston 7 has a hinge 1 whose axis is arranged tangentially to the axis of the adjusting piston 7.
3 carries a lever 12 which is supported at its free end on a spring 14. Spring 14 is adjustable.

The control pressure measuring piston 6 is supported by a contact surface 16 of the lever 12 via a support roller 15 .
On the side opposite the piston 6, the lever 12 rests on a contact pin 17, which contacts the hole 19.
It is connected to a control slide 18 of the control valve, which is slidable within the control valve. A hole 20 opens in the hole 19 on one side and a hole 21 opens on the other side, the hole 20 connecting the inner chamber of the cylinder 3 with the hole 19, and the hole 21 opening into the piston plate 8 in the cylinder 2. The front chamber of the hole 19 is connected to the hole 19.

The mode of operation of such a device is as follows: at the start of operation, the channel 11 and thus the channel 10 are loaded with a minimum pressure. As a result, the control pressure measuring piston 6 exerts only a minimum pressure on the lever 12, so that the lever is pressed upwards in the drawing by the force of the spring 14. In this case, the lever 12 carries the control slide 18 upwards by the action of a spring (not shown) or by an articulated connection between the contact pin 17 and the lever 12, so that the lower edge of the control slide 18 pulls the control slide 18 into the hole. 21 and hole 19
are connected. Since a certain amount of pressure still remains in the passage 10, this pressure causes the control piston 7 to slide to the left in the drawing, so that the liquid in front of the end face of the piston plate 8 flows into the hole 21.
It is forced through the hole 19 and from there flows into the interior of the casing. control slider 18
The lower collar simultaneously closes the bore 20, so that a pressure is built up in the cylinder 3, under the influence of which the adjusting piston 7 slides to the left in the drawing until it reaches its end position, which In the end position, the pump associated with the adjustment lever 9 reaches the adjustment position of maximum stroke volume per revolution. When the pressure in the channel 11 and thus in the channel 10 increases, the control pressure measuring piston 6 presses the lever 12 with a relatively large force, so that the lever resists the force of the spring and the control slide 18 connects the holes 20, 21 with each other. , so that the pressure is guided from cylinder 3 to cylinder 2 in front of piston plate 8 . Since the piston plate 8 has a larger end surface than the adjusting piston 7 in the cylinder 3, the adjusting piston slides to the right in the drawing. In this case, the adjusting piston 7 carries the lever 12, so that the distance between the line of action of the force on the control pressure measuring piston 6 and the line of action of the axial force on the hinge 13 is reduced, whereas the spring 14 and the hinge The distance between the line of action and the shaft remains the same, so that in the case of a certain force of the spring 14, the control pressure measuring piston 6 is returned and the lower collar of the control slide 18 is inserted into the hole 20, 21 will be closed. In this case cylinder 2
Since the inner chamber is closed in front of the piston plate 8, the adjusting piston 7 is held fixed in the achieved position. If the pressure is increased further, the lever 12 is returned again against the force of the spring 14 and the control slide 18 is again slid as follows. That is, the bores 20, 21 are connected to each other until the adjusting piston 17 reaches a position corresponding to the lowest stroke volume of the pump, for example the zero stroke position.

In the apparatus shown in FIG. 2, the parts 1 to 4, 8, 12, 13, 17, 20 shown in FIG.
21 are given the same reference numerals. Instead of the spring 14, a spring 24 is provided which abuts against a spring ferrule 25, and the position of the spring ferrule is adjusted relative to the lever 12 by the adjusting screw 2.
Adjustable through 6. Furthermore, a second spring 27 is provided, which is supported on one side in a borehole 29 designed as a blind borehole and is compressed against the control slider 28 on the other side, the control slider causing the borehole to be compressed. 20 or the bore 21 is selectively blocked, or the bore 20 is connected with the bore 21, or the bore 21 is connected to the bore 3 through which the pressure medium flows from the chamber in front of the piston end face in the cylinder 2 into the interior of the casing.
Connected to 0.

Pressure member 31 against contact surface 16 of lever 12
are in abutment and the pressure member is guided in the bore 32, so that due to the slight friction produced on the surface 16 by friction a lateral force is received in the bore 32 and the pressure member It is slid only in the axial direction of the hole 32. Two mutually parallel holes 34, 35 are provided in the housing part 33;
The piston 36 is slidable within the hole 35
A piston 37 is slidable within. The bore 35 is connected to a conduit 38, which leads on one side to the chamber of the cylinder 3 and on the other side to a conduit 39, which itself is connected to the discharge conduit of the pump; The adjusting member of the discharge conduit is connected to the adjusting piston 7. The bore 34 is connected to a conduit 40, which itself is connected to the discharge conduit of the second pump, which is provided with the adjustment device described above.

This causes the entire force produced by the pistons 36, 37 to act on the pressure member 31. According to a further embodiment of the invention, a switching valve (not shown) is provided, which functions satisfactorily even when the discharge pressure conduit connecting the regulating device with the cylinder 3 is pressureless. The cylinder 3 is connected in all cases with a pressure-conducting outlet pressure line.

An outflow conduit 45 connects to the chamber of the cylinder 2, in which a narrow constriction point is arranged.

When the lever 12 returns due to the force of the spring 14,
As a result of the control slide 28 causing pressure medium to flow out of the cylinder 2, an outlet hole 30 is formed in the adjusting piston 7. Outflow conduit 45 and outflow hole 30
Both are not necessary; either one is sufficient.

The embodiment shown in FIG. 3 corresponds to the embodiment shown in FIG.
Portions corresponding to 40 are designated by numerals 101 to 140. However, in this embodiment the pressure member 131 is designed as a piston, which piston is slidable in a cylinder 132 which is connected to the second pump, which is confined in the annular chamber 141 by the bore 134. Connected to pressure.

The embodiment according to FIG. 4 differs from the embodiment according to FIG. 3 only in the construction of the spring 124 and its bearing.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway schematic diagram showing a first embodiment of the adjusting device, FIG. 2 is a schematic diagram showing a second embodiment, and FIG. 3 is a partially cutaway diagram showing a third embodiment. FIG. 4 is a partial longitudinal sectional view showing a fourth embodiment. 1...Casing part, 2, 3...Cylinder,
4...Casing part, 5...Cylinder, 6...
Control pressure measuring piston, 7... Adjustment piston, 8...
...Piston plate, 9...Adjustment lever, 10.
11... Passage, 12... Lever, 13... Hinge, 14... Spring, 15... Support roller, 16...
... Contact surface, 17 ... Contact pin, 18 ... Control slider, 19, 20, 21 ... Hole, 24 ... Spring,
25... Spring rattle, 26... Adjustment screw, 27...
Spring, 28... Control slider, 29... Hole, 30
... hole, 31 ... pressure member, 32 ... hole, 33 ...
...Casing part, 34/35...hole, 36/3
7... Piston, 38/39/40... Conduit, 4
5... Outflow conduit, 124... Spring, 131... Pressure member, 132... Cylinder, 134... Hole, 1
41...Annular chamber.

Claims (1)

[Scope of Claims] 1. An adjusting piston connected to an adjusting member of the transmission and loaded with pressure from both sides, and a control valve for controlling the pressure in both pressure chambers in front of both end faces of the adjusting piston. A regulating device for a hydrodynamic transmission, comprising a control pressure measuring piston which is slidably arranged in the casing and is loaded by the working pressure of the transmission, the control pressure measuring piston comprising: abutting a lever, which lever is pivotally connected at one end via a hinge to an adjusting piston and is supported on this adjusting piston via an elastic support member, and which actuates the control valve. In a version configured to An adjusting device for a hydrodynamic transmission device, characterized in that: 2. The regulating piston has working surfaces of different sizes on both sides, each assigned to a pressure chamber, and the control valves 18, 19, 28, 29,
2. Regulating device for a hydrodynamic transmission according to claim 1, characterized in that holes 128, 129 extend in the regulating piston and connect the two pressure chambers to each other at one position of the control valve. 3 Spring 24, 15 forming an elastic support member
2. Adjusting device for a hydrodynamic transmission according to claim 1, wherein 0 is adjustable. 4 Support members 31 which are arranged parallel to one another and are abutted by single pressure-measuring pistons 36, 37, each connected to a delivery conduit of the transmission, and which are respectively slidable in a cylinder 34, 35; 2. The adjusting device for a hydrodynamic transmission according to claim 1, wherein the control pressure measuring piston is configured as a pressure measuring piston. 5. Regulating device for a hydraulic transmission according to claim 4, wherein the end face of the single pressure-measuring piston operates in proportion to the maximum stroke volume of the respective assigned transmission. 6. Adjustment device for a hydrodynamic transmission according to claim 1, wherein the elastic support member is designed as a pressure-loaded piston.