DE102018212148A1 - Hydro machine with damping hose for the adjustment device - Google Patents

Abstract

Disclosed is an adjustable hydraulic machine, preferably an axial piston pump, with an adjustment unit, preferably with a pressure regulator or a pressure control valve, as well as other hydraulic-hydraulic-mechanical or hydraulic-electrical regulators, e.g. Flow controller, el. Pressure controller, power control, el. Swivel angle controller. A damping hose for reducing pressure pulsations is connected to the adjustment unit and, in the preferred embodiment, is inserted into a pressure medium sink, e.g. opens into a housing of the hydraulic machine. A nozzle in the damping hose limits the loss of pressure medium. This loss of pressure medium is compensated for by the pressure regulator or the pressure control valve.

Description

Technical field

The present disclosure relates to a damping hose for a hydraulic adjustment device of a hydraulic machine. The damping hose is preferably optimized for life and preferably also offers a cooling function for the actuating pressure medium of the adjusting device.

• • Elastische Energieaufnahmen und spätere Abgabe und/oder
• • Umwandlung der Druckpulsation in Wärme.

Hydraulic hoses are known from the prior art which transport working or delivery pressure media, for example from a hydraulic pump to a destination. Since these hoses are flexible and elastic, they also change or compensate for a pressure pulsation of the working or delivery pressure medium. The compensation of pressure pulsations works through the following two effects:

• • Elastic energy consumption and later release and / or
• • Conversion of the pressure pulsation into heat.

Hydraulic pumps are also known from the prior art, whose stroke volume can be adjusted by means of a hydraulically operated adjusting device. The applicant's data sheet RE 92703 entitled "Axial piston variable pump A10VO series 52 and 53" Edition 2.2015 shows such a hydraulic pump, which is equipped with a pressure flow regulator (DRF). The actuating pressure medium of the adjusting device is tapped from the working or delivery pressure medium of the hydraulic pump, so that its pressure medium pulsations are disadvantageously transmitted to the adjusting device.

The object of the present invention is to reduce or eliminate the pressure pulsations of the actuating pressure medium of the adjusting device of a hydraulic machine.

The claimed hydraulic machine has an adjusting device, by means of which a stroke volume of the hydraulic machine can be adjusted. The adjusting device is operated with actuating pressure medium, which is branched off from a working channel or high-pressure channel of the hydraulic machine. According to the invention, a damping hose is connected to the adjusting device via a hose connection, which damping hose can be filled or filled with control pressure medium or through which it flows. This damping hose is therefore not a transport hose and not a signal hose. Therefore, no adjustable valves and no hydraulic units are connected to its end section spaced from the hose connection. The pressure pulsations of the actuating pressure medium are thus reduced or eliminated.

In a particularly preferred development, it is therefore possible to adapt a length and / or a diameter and / or an elasticity of the damping hose specifically to the pressure pulsation of the actuating pressure medium.

In a preferred development, the damping hose is designed with a — preferably metallic — spiral reinforcement. Such hoses are for example in the US 3,729,028 disclosed. With the spiral reinforcement, the service life of the damping hose according to the invention and / or its resistance to higher actuating pressures are increased. In addition, the adaptation to the pressure pulsation can be made possible or improved.

In a particularly preferred development, the damping hose also serves to cool the actuating pressure medium. For this purpose, the damping hose is arranged essentially over its entire length outside a housing of the hydraulic machine - preferably at a distance from the housing.

If the hydraulic machine is a hydraulic pump, it is particularly preferred if the adjusting device has a flow control valve. In addition, the signal pressure of the signal pressure medium can be controlled or regulated such that the delivery pressure of the hydraulic pump is higher than a control pressure by the equivalent of a spring.

The control pressure can be a load-sensing pressure, i.e. the highest load pressure of all consumers supplied by the hydraulic pump. The delivery pressure of the hydraulic pump can thus be reduced and adapted to the highest load consumer. This can save energy.

The adjusting device preferably has a pressure regulating valve or another hydraulic or hydraulic-mechanical or hydraulic-electrical regulator (e.g. flow regulator, electrical pressure regulator, power regulator, electrical swivel angle regulator), by means of which the discharge pressure of the hydraulic pump can be limited. For this purpose, the signal pressure is preferably increased and the delivery volume is reduced. In the case of an axial piston pump, its swivel angle is then reset.

The pressure regulating valve is preferably continuously adjustable between a first and a second position, the delivery pressure of the hydraulic pump being applied to an actuating chamber in the first position, and the actuating chamber being connected to a pressure medium sink (e.g. housing or tank connection of the hydraulic pump) in the second position , The delivery pressure acts on the pressure control valve against a spring in the direction of the first Position. The spring of the pressure control valve is stronger than that of the flow control valve.

The pressure regulating valve is preferably connected to the actuating chamber via an actuating pressure channel without the interposition of further adjustable valves.

If the adjusting device has an actuating cylinder with an actuating chamber, the hose connection is preferably arranged on the actuating chamber or on an actuating pressure line or on an actuating pressure channel. The control pressure line or the control pressure channel connects the pressure control valve or the other controller to the control chamber. The hose connection is preferably arranged adjacent to the control chamber.

Preferably, a throttled connection branches off from the signal pressure line or from the signal pressure channel to the pressure medium sink between the hose connection and the pressure control valve. For example, with two nozzles.

In a first exemplary embodiment, the damping hose is closed at an end section opposite the hose connection. The damping hose thus forms a branch channel that does not flow through. In this case, the damping hose can be bent predominantly or essentially in an annular manner, the end section being arranged adjacent to the hose connection. The damping hose can e.g. form an arc at about 270 degrees. and e.g. in the assembled state of the hydraulic machine.

Since the heat of the actuating pressure medium and the heat due to the pulsation damping stress the damping hose, the damping hose has a connection to the pressure medium sink at the end section opposite the hose connection in a second particularly preferred embodiment. A flow of the signal pressure medium through the damping hose and thus a supplementary cooling function of the damping hose is thus provided or greatly improved. There is also a pressure-dependent displacement of nodes. More specifically, the thermally stressed point of the damping hose shifts depending on the signal pressure.

A preferred direction of flow in the assembled state of the hydraulic machine is from top to bottom.

In a preferred development of the second exemplary embodiment, the damping hose has a nozzle or throttle or orifice. The loss of signal pressure medium is thus minimized. The nozzle or throttle or orifice is preferably arranged on the end section of the damping hose which lies opposite the hose connection. There is a damping effect through the nozzle or throttle or orifice. Additional losses can be avoided if, according to the prior art, a nozzle is provided between the signal pressure line and the pressure medium sink, and this is replaced by the nozzle in the damping hose, that is to say it is only moved to another location.

In the installed state of the hydraulic machine and thus of the damping hose, a direction of flow of the signal pressure medium through the damping hose from top to bottom is preferred, the nozzle then being at the bottom.

In particular with the pressure control valve and / or the flow control valve, the second preferred exemplary embodiment with the nozzle is advantageous since the integral behavior of the controllers both also compensates for the pressure loss of the actuating pressure medium via the nozzle. Optimized cooling of the signal pressure medium is thus combined with unrestricted controllability or controllability of the hydraulic machine. This training also has no negative impact on the dynamics of the hydraulic pump.

The damping hose can be curved, e.g. run approximately semicircular and spaced from the housing.

list of figures

• 1 ist ein Schaltplan des bevorzugten Ausführungsbeispiels der erfindungsgemäßen Hydropumpe;
• 2 ist eine perspektivische Darstellung der Hydropumpe aus 1.

The preferred exemplary embodiment of the hydraulic machine according to the invention is described in detail below with reference to the figures.

• 1 is a circuit diagram of the preferred embodiment of the hydraulic pump according to the invention;
• 2 is a perspective view of the hydraulic pump from 1 ,

Description of the preferred embodiment

1 shows the circuit diagram of the preferred embodiment of the hydraulic pump, as an axial piston pump with adjustable swash plate 1 is trained. The swashplate 1 is via an adjustment device 2 pivotable, whereby the delivery volume of the axial piston pump can be changed. An actuating cylinder is used for this 4 , which is designed as a differential cylinder, and a control chamber 6 having. When the control chamber is filled 6 the swash plate is used with pressure fluid 1 pivoted back, thereby reducing the delivery volume of the hydraulic pump.

The hydraulic pump has a housing 8th , on which a suction connection S and a high pressure connection B are formed, which are flowed through by working pressure medium.

In a manner known from the prior art, a high-pressure duct HD which is an engine 10 the hydraulic pump with the high pressure connection B connects, working fluid branched off, with a pump regulator 12 is supplied. The pump regulator 12 has a pressure control valve 14 and a flow control valve 16 on. Both valves 14 . 16 are designed as adjustable 3/2-way valves and in series with the control chamber 6 of the actuating cylinder 4 connected. More specifically, is a connection of the flow control valve 16 with the control chamber 6 only via the pressure control valve 14 possible.

The flow control valve regulates the operation of the preferred embodiment of the hydraulic pump according to the invention 16 continuously a signal pressure in the control chamber 6 , why the pressure control valve 14 in the in 1 shown pass position is switched. For this, the flow control valve 16 in the direction of an increase in the signal pressure from the delivery pressure of the hydraulic pump. A spring counteracts this in the direction of a reduction in the signal pressure 18 and a control pressure X ,

The pressure control valve 14 acts as a pressure limiter and intervenes when the delivery pressure of the hydraulic pump is the equivalent of a spring 20 exceeds.

A connection of the pressure control valve 14 is via a signal pressure channel 22 with the control chamber 6 connected. This signal pressure channel 22 is over a throttled connection 24 with a pressure fluid sink T an interior of the housing in the embodiment shown 8th is connected.

Between the branch of the throttled connection 24 and the control chamber 6 and thus in closer proximity to the control chamber 6 is via a hose connection 26 a damping hose 28 connected. It serves to reduce pressure pulsations from the engine 10 via the high pressure duct HD in the pump controller 12 be transmitted. This is the damping hose 28 Made with a metallic spiral reinforcement and dimensioned in length and elasticity in such a way that the pressure pulsation is optimally dampened.

The damping hose 28 is flowed through by a small amount of signal pressure medium. To do this, the damping hose 28 at his from the hose connector 26 spaced end portion of a nozzle 30 , via the signal pressure medium into the pressure medium sink T is dissipated. The damping hose thus also serves to cool the actuating pressure medium.

2 shows the hydraulic pump in a perspective view 1 , On the case 8th is the suction connection S educated. In the in 2 Installation position of the hydraulic pump shown is on an upper side of the housing 8th the pump controller 12 assembled. In this area is on the housing 8th the hose connection 26 provided on the the curved damping hose 28 is scheduled.

According to the in the installation position 2 lower part of the case 8th is the nozzle 30 attached, which is integral with a connection of the damping hose 28 in the lower part of the interior of the housing 8th and thus opens into the pressure medium sink. It can be seen that the damping hose 28 arcuate - in particular semicircular - and spaced from the housing 8th runs. This allows ambient air to absorb the heat from the damping hose 28 and thus dissipate the heat of the signal pressure medium.

Disclosed is an adjustable hydraulic machine, preferably an axial piston pump, with an adjustment unit, preferably with a pressure regulator or a pressure regulating valve, as well as other hydraulic-hydraulic-mechanical or hydraulic-electrical regulators, e.g. Flow controller, el. Pressure controller, power control, el. Swivel angle controller. A damping hose for reducing pressure pulsations is connected to the adjustment unit and, in the preferred embodiment, is inserted into a pressure medium sink, e.g. opens into a housing of the hydraulic machine. A nozzle in the damping hose limits the loss of pressure medium. This loss of pressure medium is compensated for by the pressure regulator or the pressure control valve.

LIST OF REFERENCE NUMBERS

1

swash plate

2

adjustment

4

actuating cylinder

6

setting chamber

8th

casing

10

engine

12

pump regulator

14

Pressure control valve

16

Flow control valve

18

feather

20

feather

22

Actuating pressure channel

24

throttled connection

26

hose connection

28

damping hose

30

Nozzle or throttle or orifice

B

High pressure port

HD

High pressure passage

S

suction

T

Pressure medium sink

X

control pressure

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 3729028 [0007]

Claims (11)

Hydraulic machine whose stroke volume can be adjusted via an adjusting device (2), the actuating pressure medium of which is tapped from the working pressure medium, characterized in that a damping hose (28) which can be filled or filled with or through which the actuating medium is filled is connected to the adjusting device (2) via a hose connection (26) , Hydro machine after Claim 1 , A length and / or a diameter and / or an elasticity of the damping hose (28) being / being adapted to a pressure pulsation of the actuating pressure medium. Hydro machine according to one of the preceding claims, wherein the damping hose (28) is designed with a spiral reinforcement. Hydro machine according to one of the preceding claims, wherein the damping hose (28) is arranged substantially or over its entire length outside a housing (8) of the hydraulic machine. Hydraulic machine according to one of the preceding claims, which is a hydraulic pump, the adjusting device (2) having a pressure regulating valve (14) or a hydraulic or hydraulic-mechanical or hydraulic-electric regulator, by means of which or via which the delivery pressure of the hydraulic pump can be limited. Hydro machine after Claim 5 , The adjusting device (2) has an actuating cylinder (4) with an actuating chamber (6), and wherein the hose connection (26) is arranged on the actuating chamber (6) or on an actuating pressure line or on an actuating pressure channel (22), which which connects the pressure control valve (14) or the regulator to the control chamber (6). Hydro machine after Claim 6 , A throttled connection (24) branches off from the signal pressure line or the signal pressure channel (22) to a pressure medium sink (T) between the hose connection (26) and the pressure control valve (14). Hydro machine according to one of the preceding claims, wherein the damping hose is closed at an end section opposite the hose connection. Hydro machine according to one of the Claims 1 to 7 The damping hose (28) has a connection to a pressure medium sink (T) at an end section opposite the hose connection (26). Hydro machine after Claim 9 wherein the damping hose (28) has a nozzle or throttle or orifice (30). Hydro machine according to one of the preceding claims, wherein the damping hose (28) is arcuate.

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