DE102007056684A1 - accumulator - Google Patents

Abstract

The invention relates to a pressure accumulator (2) having a housing (9), a displaceable element (10) arranged within the housing (9) and an energy accumulator (23), the displaceable element (8) having a first pressure surface (10), wherein the first pressure surface (10) and the housing (9) at least partially delimit a storage space (12) and wherein the displaceable element (8) can be displaced against the force of the energy storage device (23) by pressurizing the storage space (12).

Description

Field of the invention

The The invention relates to a pressure accumulator having a housing, a displaceable disposed within the housing Element and a power storage, wherein the movable element a first pressure surfaces, wherein the first pressure surface and the housing at least partially limit a storage space and wherein the displaceable element by pressurizing the storage space are moved against the force of the energy storage can.

Background of the invention

accumulator are used in a variety of applications during the operation of the application pressure medium, which from a pressure source, for example, a pressure medium pump is supplied to record and this when needed the application again to deliver. Conceivable applications in vehicle technology are, for example automated gearbox, automatic transmission, hydraulically operated, Switchable valve train components (rocker arms, supporting elements, Cup or roller tappets), camshaft adjusters, brake systems or similar.

Such an accumulator is for example from the DE 42 02 905 A1 known. The accumulator has a formed in a housing made of aluminum, blunt-ended cylinder bore. In the cylinder bore a longitudinally movable pressure piston is added. This separates a pressure medium receiving, variable volume reservoir, which is formed within the housing, from a breathing chamber in communication with the atmosphere. In the reservoir opens a connection hole through which pressure medium can be moved. The breathing chamber is closed by a cap inserted into the cylinder bore. In the housing, a helical compression spring is also included. This engages in the pressure piston and is supported with bias on the one hand at the bottom of the pressure piston and on the other hand indirectly via the closure cap on the housing. The compression spring supports the delivery of pressure medium received in the storage space and returns the pressure piston to the initial position in which the storage space has a minimal volume.

is the force acting on the pressure piston and out of the hydraulic system prevailing pressure results larger than that this counteracting force of the compression spring, so fills the accumulator. In this case, the pressure piston within the housing shifted against the force of the compression spring, causing the volume of the Pantry rises.

Sinks the pressure in the hydraulic system from, so the pressure piston is through the compression spring is moved in the direction of the starting position until the forces acting on the plunger, opposing forces balanced. As a result, the stored in the pantry Pressure medium supplied to the hydraulic system again. there corresponds to that of the pressure accumulator at the beginning of its emptying provided pressure, the pressure, right before the start of emptying prevailed in the hydraulic system.

adversely in this embodiment, that the pressure assist the application to which the accumulator is assigned is not over the pressure value can be out, the directly before the start of the pressure support prevailed in the hydraulic system.

Around to ensure the functional safety of the application must the pressure medium pump, which is assigned to the hydraulic system, be designed for the peak demands of the applications. Especially in applications where no nearly constant load prevails, but short-term demand peaks must exist the pressure medium pump are designed for this, whereby the pressure medium pump oversized for most of the operation is. It would also be conceivable to use a controllable pressure medium pump, the according to the current needs of the application pressure medium promotes or provides the required system pressure.

Both Solutions increase the cost of the application and require an increased space. simultaneously decreases due to the larger design of the pressure medium pump the efficiency of the application.

Object of the invention

Of the Invention has for its object to provide a pressure accumulator, which eliminates the aforementioned disadvantages, wherein a functionally reliable operation the application in each phase of operation is to be ensured. It is intended to oversize the pressure medium pump (Interpretation of the expected peak loads) also omitted can be as the use of variable pressure fluid pumps.

The object is achieved in that the displaceable element has a second pressure surfaces, wherein the second pressure surface and the housing define a control space at least partially, wherein the displaceable element by Druckmittelbeaufschlagung the control chamber can also be moved against the force of the force accumulator and wherein the pressure accumulator is designed such that a pressure fluid flow is locked within the accumulator between the control room and the reservoir at least in the direction of the control room or can be locked.

there can be provided that the pantry with a consumer communicated. Alternatively, it can be provided that the storage room with a consumer is connectable.

In a development of the invention, the control room with no pressure be connected to a tank. It can be provided that the Reservoir at the same time not communicating with the tank.

As well Conceivable are embodiments in which the control room can be emptied independently of the storage room.

advantageously, can the control room during the operation of the application optionally connected to a pressure source or a tank.

there Control means may be provided, wherein the control room by means of the control means optionally with a tank or a pressure source can be connected.

In a concretization of the invention is provided that a pressurizing of the Storage space displaces the displaceable element in the same direction, as a pressurizing of the control room. Furthermore can be provided that the pantry with a consumer at least connectable, the control room connected to a tank is and the ratio between the minimum flow area between the control room and the tank and the minimum flow area between the pantry and the consumer bigger is, as the ratio between the area the second printing surface and the surface area the first printing surface.

In an embodiment of the pressure accumulator is provided that within the accumulator no connection between the Storage room and the control room exists, d. H. the storeroom and the control room within the pressure accumulator do not communicate with each other.

The displaceable element may for example be designed as a pressure piston which is within a housing against the force be moved as a spring element formed energy storage can. Alternatively, other forms of energy storage Use find, for example, reversibly deformable body, for example, made of elastomers, or gas-filled bubbles. The formation of the pressure accumulator with a verlagerba ren Element which spaces isolated from each other within the accumulator partially limited, these two can Rooms controlled separately, d. H. filled and / or emptied. Apart from possibly occurring Leakage is no connection between the rooms. So For example, different pressure sources for Filling the pantry and the control room used become.

alternative can also be a pressure medium connection between the pantry and be provided to the control chamber within the pressure accumulator. lever which is supplied to the control room can over enter this pressure medium connection in the storage room. It is but to ensure that a reverse fluid flow, is suppressed by the storage room in the control room. This can for example via a pressure medium channel in the pressure piston or the housing of the pressure accumulator can be realized, in which a check valve is arranged. In this case can the filling of the pantry and the control room done by filling the control room alone. Should the accumulator be emptied, the control room is on tank switched. The storage room empties into the hydraulic system, the control room depressurized into the tank. A transfer of Pressure medium from the storage space in the control room is by the Check valve prevents.

ansteigen, abhängig von der Last, die zu diesem Zeitpunkt auf den Kraftspeicher wirkt. Dabei entspricht A₁ dem Flächeninhalt der ersten Druckfläche und A₂ dem Flächeninhalt der zweiten Druckfläche. Wird als Kraftspeicher beispielsweise ein Federelement eingesetzt, so steigt der Druck bei Beginn des Unterstützungsvorgangs um den vollen Faktor

an, solange die Feder noch nicht ihren maximal komprimierten Zustand erreicht hat. Der maximal komprimierte Zustand kann beispielsweise durch einen oder mehrere Anschläge innerhalb des Gehäuses oder den maximale Kompressionsweg der Feder definiert sein.If it is provided that a pressurization of the storage space displaces the displaceable element in the same direction as a pressurizing of the control space, the control space can support the filling of the storage space. For this purpose, the control chamber is also filled with pressure medium during the filling process of the storage space. As a result, a force acts on both pressure surfaces of the pressure piston, whereby a higher force is stored in the energy store (the spring element is compressed more strongly). If the filled pressure accumulator receives the command to support the application assigned to the accumulator, the control chamber can be emptied independently of the reservoir. That is, while the reservoir is being drained into the hydraulic system of the application and thus supporting the hydraulic system, the control chamber may be vented against atmospheric pressure in a tank. The tank may be the pressure medium reservoir of the application or another buffer. By suitable design, the venting of the control chamber can be done faster than the emptying of the reservoir into the hydraulic system. Thus, the ge velvet force, which was stored in the energy store, over the first pressure surface on the pantry. As a result, the pressure at the beginning of the assist process can be reduced by up to a factor of

increase, depending on the load that acts on the energy storage at this time. Here A ₁ corresponds to the surface area of the first pressure surface and A ₂ corresponds to the surface area of the second pressure surface. If, for example, a spring element is used as the force store, then the pressure at the start of the assistance process increases by the full factor

as long as the spring has not yet reached its maximum compressed state. The maximum compressed state may be defined, for example, by one or more stops within the housing or the maximum compression travel of the spring.

The Invention is based on that a displaceable element of the pressure accumulator at least two separate, acted upon with pressure medium spaces limited in the direction of displacement of the element. At least one is of the rooms (storeroom) with the hydraulic system of the application connected or connectable. Furthermore, at least one more Room (control room) during the filling process of the Reservoir also charged with pressure medium and during the emptying process of the reservoir faster than this emptied. This can, for example, against atmospheric pressure, in a tank respectively. Thus, the control room supports the filling process such that the displaceable element deflected more is, as this without pressurization of the control room of the Case would be.

By increasing the pressure provided by the accumulator, the pressure accumulator can catch peak consumption, so that the pressure medium pump designed for normal operation of the application can be. They are not oversized or regulated Pressure medium pumps needed to ensure a reliable and fast Respond to the pressure medium requirement of the application.

When Pressure source, which acts on the control chamber with pressure medium can For example, the hydraulic system or its pressure medium pump or a separate source, such as a separate pressure medium pump serve. In the second case, even in low-power operating phases System pressure of accumulator completely filled become. The optional connection to a pressure source or the Tank is via control means, for example a 3/2-way valve in the form of a switching valve (eg seat valve) or a proportional valve (For example, slide valve), produced. Alternatively, there are two Control means in consideration, wherein one of the control means the connection Pressure source → control room and the other control means the Control room connection → Tank locks or releases. The Control means may, for example, electromagnetically actuated Hydraulic valves, such as directional control valves (eg switching or proportional valves), be openable check valves or the like. These Control means obtained from a controller of the application Control signals according to which the pressure accumulator fills or being emptied. Thus, a variety of support strategies will be realized.

advantageously, can in the hydraulic system between the control room and the pressure source a Provided check valve, which a pressure medium flow blocks from the control room in the direction of the pressure source. Thus, will located in the control chamber pressure fluid volume up to its Connection with a tank included. This will make the relocatable Element held in the deflected position, even if the system pressure drops and thus unintentional emptying of the storage room prevented.

The pressure support of the pressure accumulator can be activated by simply switching one or more control means. In this case, the pressure medium volume is provided, which is stored in the operating phases of the application with low pressure medium consumption in the storage space. Depending on the embodiment, the pressure maintained by the pressure accumulator either corresponds to the current system pressure multiplied by a factor which can amount to 1 + A ₂ / A ₁ (embodiment without check valve) or a maximum system pressure present during the filling phase multiplied by the same factor (embodiment with check valve). The full factor 1 + A ₂ / A ₁ is always present when the full storage capacity of the energy storage has not been exhausted, for example. The spring element is not yet compressed to block or the displaceable element is still applied to the attacks.

In one embodiment of the invention, it is provided that the displaceable element has a third pressure surface, which at least partially limits a counterpressure space, wherein a pressure medium loading of the counterpressure space displaces the displaceable element in the opposite direction, such as a pressure medium loading the control chamber or the storage space. Thus, the force exerted by the force accumulator on the displaceable element to the force of the pressure in the counter increased pressure chamber caused force.

Brief description of the drawings

Further Features of the invention will become apparent from the following description and from the drawings in which embodiments of the invention are shown simplified. Show it:

1 a hydraulic system containing a first embodiment of a pressure accumulator according to the invention,

2 A second embodiment of a pressure accumulator according to the invention,

3 a further hydraulic system containing a further embodiment of a pressure accumulator according to the invention.

Detailed description the drawings

1 shows a hydraulic system 1 a first embodiment of a pressure accumulator according to the invention 2 assigned.

The hydraulic system 1 has a consumer 3 on, from a pressure source, which in the illustrated embodiment as a pressure medium pump 7 is executed, via a pressure medium line 4 can be acted upon with pressure medium. To a backflow of pressure medium from the consumer 3 to the pressure medium pump 7 To prevent it is a check valve 5a in the pressure medium line 4 provided, which a pressure medium flow from the pressure medium pump 7 to the consumer 3 allows, but blocks an opposite pressure medium flow.

There is also a tank 6 provided, from which the pressure medium pump 7 Supplied pressure medium and in the pressure medium from the consumer 3 can be dissipated.

The hydraulic system 1 is a pressure accumulator 2 assigned to the one as a pressure piston 8th executed displaceable element comprising a housing and a power storage. The pressure piston 8th is inside the case 9 arranged and can be moved against the force of a force accumulator. In the illustrated embodiment, the energy accumulator is a spring element 23 executed. However, other types of energy stores are also conceivable, for example suitably shaped elastomer bodies or gas-filled bubbles.

The pressure piston 8th has two pressure surfaces 10 . 11 on. Together with the case 9 limits the first pressure area 10 a pantry 12 , wherein the first pressure surface 10 the pantry 12 in the direction of displacement of the pressure piston 8th limited. The housing 9 and the plunger 8th limit a control room 13 , wherein the second pressure surface 11 the control room 13 also in the direction of displacement of the pressure piston 8th limited. Here are the pressure piston 8th and the case 9 designed such that within the pressure accumulator 2 no connection between the two rooms 12 and 13 consists.

Apart from leakage, there is no pressure medium exchange between these pressure chambers in this embodiment 12 . 13 instead of. In the illustrated embodiment, the pressure surfaces 10 . 11 in the direction of displacement of the pressure piston 8th arranged offset to one another, wherein the first pressure surface 10 in the plane, that of the direction of displacement of the pressure piston 8th is pierced vertically, from the second pressure surface 11 is enclosed. The first printing surface 10 is circular and the second pressure surface 11 ring-shaped. By pressurizing the rooms 12 . 13 becomes the pressure piston 8th against the force of the spring element 23 shifts, reducing the volume of the rooms 12 . 13 increases. The way the pressure piston 8th against the spring element 23 is displaced by stops 14 limited within the housing 9 are formed. The attacks 14 are arranged such that a connection of the storage space 12 with the control room 13 is prevented.

The spring element 23 relies on the one hand at the pressure chambers 12 . 13 opposite side of the pressure piston 8th and on the other hand at the pressure chambers 12 . 13 opposite side of the housing 9 from. In this case, the spring element with bias in the accumulator 2 mounted so that the volume of the pressure chambers 12 . 13 is minimal at low system pressure. In this initial position, the pressure piston is located 8th on whose the spring element 23 opposite side to the housing 9 at.

Between the pantry 12 and the hydraulic system 1 is stock management 15 intended. The supply line 15 opens on the one hand downstream of the check valve 5a in the hydraulic system 1 and on the other hand via a first pressure medium connection 24 in the pantry 12 , The control room 13 can optionally with a tank 6 or by means of a control line 16 be connected to a pressure source. In the illustrated embodiment serves as a pressure source, the pressure medium pump 7 of the hydraulic system 1 , The control line 16 opens on the one hand upstream of the check valve 5a in the pressure medium line 4 and on the other hand via a second pressure medium connection 25 in the control room 13 , Also conceivable are embodiments in which a different pressure source, for example a separate pressure medium pump is used.

To the pressure medium flow to and from the control room 13 to control is a control means 17 in the form of a directional valve 18 intended. The directional valve 18 has a pressure port P, a control chamber port A and a drain port T. The pressure port P is connected to the pressure medium pump 7 of the hydraulic system 1 connected. The control room connection A is with the control room 13 and the drain port T to the tank 6 connected. In a first control position of the directional control valve 18 the control room terminal A is connected to the pressure port P, while the drain port T communicates with none of the other ports P, A.

In a second control position of the directional control valve 18 the control room port A is connected to the drain port T while the pressure port P is not communicating with any of the other ports T,.

In addition, another check valve 5b be provided, which in the control line 16 is arranged and a backflow of pressure medium from the control room 13 for pressure medium line 4 prevented.

wobei A₁ dem Flächeninhalt der ersten Druckfläche 10, A₂ dem Flächeninhalt der zweiten Druckfläche 11, p_max dem während der Befüllphase maximal auftretenden Systemdruck und D der Federkonstante des Federelements 23 entspricht. Dabei ist der maximale Verschiebeweg durch die Anschläge 14 begrenzt. Unter der Ausgangsstellung ist der Zustand des Druckkolbens 8 zu verstehen, in der das Federelement 23 maximal entspannt ist.During normal operation of the consumer 3 in which the of the pressure medium pump 7 provided pressure fluid volume or the pressure provided to the consumer 3 to operate, there is the directional control valve 18 in the first position. Thus, pressure medium reaches both via the supply line 15 in the pantry 12 , as well as over the control line 16 in the control room 13 , That in the pantry 12 or the control room 13 introduced pressure medium acts on the pressure surfaces 10 . 11 whereby the pressure piston 8th in the direction of the attacks 14 against the force of the spring element 23 is moved so that the volume of both the pressure chambers 12 . 13 increases. The pressure in the hydraulic system drops 1 , For example, due to an increased pressure medium requirement of the consumer 3 , so the pressure in the pantry sinks to the same extent 12 , Due to the pressure gradient between the control room 13 and the hydraulic system 1 closes the check valve 5b in the control line 16 , causing a pressure drop in the control room 13 and a pressure medium flow can be avoided from this. This has the consequence that the volume of the control room 13 and the pantry 12 despite the pressure drop in the hydraulic system 1 remains constant. It applies to the path x, the pressure piston 8th was deflected from its rest position:

where A _{1 is} the area of the first printing surface 10 , A ₂ the area of the second printing surface 11 , p _max the maximum system pressure occurring during the filling phase and D the spring constant of the spring element 23 equivalent. Here is the maximum displacement by the attacks 14 limited. Under the initial position is the state of the pressure piston 8th to understand in which the spring element 23 is maximally relaxed.

solange der Druckkolben 8 noch nicht vollständig ausgelenkt wurde, also nicht an den Anschlägen 14 anliegt.Exceeds that of the consumer 3 Requested pressure medium volume or the required pressure, the capacity of the pressure medium pump 7 so becomes the directional control valve 18 transferred to its second control position. In this control position is the control room 13 with a tank 6 connected. That in the control room 13 pressurized fluid is thus connected to atmospheric pressure, thereby rapidly evacuating the control chamber 13 he follows. At the same time the storeroom becomes 12 in the hydraulic system 1 emptied. Does the pressure medium discharge of the control room 13 so fast that the pressure piston 8th exclusively via the first printing surface 10 opposite the pantry 12 supported, so affects the entire force of the spring element 23 only on the pantry 12 , Thus applies to the pressure p in the pantry 12 at the beginning of the emptying process:

as long as the pressure piston 8th was not completely deflected, so not at the attacks 14 is applied.

Because the check valve 5a in the pressure medium line 4 upstream of the supply line 15 is arranged, it is ensured that the total pressure p and the entire volume of the pantry 12 the consumer 3 is available. Thus, not only is the current system pressure or the maximum filling pressure available, as in applications with conventional pressure accumulators, but a pressure increased by up to a factor of 1 + A ₂ / A ₁ . The hydraulic system 1 can thus by adjusting the second control position on the directional control valve 18 experienced a pressure support that exceeds the support of conventional accumulators many times over. Thus, the pressure medium pump 7 on the normal operation of the consumer 3 be designed while by the consumer 3 short-term required higher pressure fluid volumes or operating pressures through the pressure accumulator 2 can be intercepted.

wobei p_sys dem bei Beginn der Druckunterstützung herrschenden Systemdruck entspricht. Denkbar ist der Einsatz dieser Ausführungsform Anwendungen in denen der benötigte Spitzensystemdruck nur geringfügig oberhalb der Kapazität der Druckmittelpumpe 7 liegt. In diesem Fall kann auf das Rückschlagventil 5b in der Steuerleitung 16 verzichtet werden, wodurch die Kosten sinken.Likewise conceivable are embodiments in which the arrangement of a check valve 5b in the control line 16 is waived. In the normal operating phases of the consumer 3 , the accumulator fills up 2 analogous to the embodiment described above. If the system pressure drops, then pressure medium flows both from the storage room 12 as well as out the control room 13 from. This leads to a pressure drop in both rooms 12 . 13 , causing a displacement of the plunger 8th leads in the direction of its rest position. Thus, in this embodiment, both the pressure medium volume which can be provided for the phase adjustment and the pressure which can be provided in the storage space 12 lowered. Nevertheless, the pressure increase takes place in the storage room 12 instead, if the directional control valve 18 is transferred to the second switching position. In this case applies to the provided pressure p at not completely deflected plunger 8th :

where p _sys corresponds to the prevailing at the beginning of the pressure support system pressure. The use of this embodiment is conceivable applications in which the required peak system pressure only slightly above the capacity of the pressure medium pump 7 lies. In this case, the check valve 5b in the control line 16 be omitted, which reduces costs.

gelten. Um dies zu erreichen ist vorgesehen, dass für den minimalen Durchflussquerschnitt zwischen dem Steuerraum 13 und dem Tank 6 A_S:

gilt, wobei A dem minimalen Durchflussquerschnitt zwischen dem Vorratsraum 12 und dem Verbraucher 3 entspricht.During the filling process of the pressure accumulator 2 the system pressure of the hydraulic system acts 1 on both the first and second printing surfaces 10 . 11 , According to the formula F = pA = p (A ₁ + A ₂ ), the energy storage takes on a greater force than would be the case with a pressure accumulator having only the pressure surface A ₁ . Will the accumulator 2 the hydraulic system 1 switched on (the directional control valve 18 transferred to the second switching position), so this increased force acts exclusively on the first pressure surface 10 on the pantry 12 , causing the in the pantry 12 prevailing pressure is increased. Prerequisite is that the control room 13 depressurized, ie a support of the energy storage on the pressure piston 8th force exerted not over the control room 13 he follows. To realize this, the ratio of the pressure medium flow from the control room must be realized 13 to the pressure medium flow from the storage room 12 Q _S / Q _V

be valid. To achieve this it is envisaged that for the minimum flow area between the control room 13 and the tank 6 A _S :

where A is the minimum flow area between the pantry 12 and the consumer 3 equivalent.

To the functioning of the pressure accumulator 2 to ensure is a vent 19 the spring chamber provided for pressure medium, which due to leakage between the pressure piston 8th and the housing 9 got into the spring chamber, into the tank 6 dissipate.

A further embodiment of the pressure accumulator according to the invention 2 is in 2 shown. Unlike the in 1 illustrated embodiment is a connecting line in this embodiment 20 inside the pressure piston 8th provided, which the storeroom 12 with the control room 13 combines. In the connection line 20 is an additional check valve 5c provided, which a pressure medium flow from the control room 13 to the pantry 12 allows an opposite pressure fluid flow but locks. The operation of the pressure accumulator 2 is essentially the same as in 1 illustrated first embodiment. In contrast to this, the pantry can 12 this embodiment on the control room 13 and the connection line 20 be filled. Thus, in the supply line 15 an additional hydraulic valve are arranged, by means of which the storage space 12 optionally from the hydraulic system 1 can be disconnected or connected to this. Will the accumulator 2 emptied, so prevails in the control room 13 a lower pressure than in the pantry 12 , Thus, the check valve closes 5c , thereby emptying the pantry 12 in the tank 6 is prevented

As an alternative to the illustrated embodiment, the connecting line including check valve 5c also in the case 9 be arranged.

3 shows a further embodiment of a pressure accumulator according to the invention 2 , This essentially corresponds to the first embodiment 1 , Unlike the first embodiment is no vent 19 provided the spring chamber. The spring chamber is rather than counter-pressure space 21 formed, which can be filled with pressure medium. The directional valve 18 is provided in this embodiment with an additional back pressure port G, which with the back pressure chamber 21 communicated.

In a first control position of the directional control valve 18 the control chamber connection A is connected to the pressure connection P, while the counterpressure connection G communicates with the outflow connection T. In a second control position of the directional control valve 18 the control room terminal A is connected to the drain port T, while the pressure port P communicates with the back pressure port G.

Is the directional valve 18 in the first Control position made no changes from the embodiment 1 on. In the second control position, however, additional pressure medium in the back pressure chamber 21 directed. This acts on a third pressure surface 22 of the pressure piston 8th with a force in the same direction as the spring element 23 acts. This will increase the pressure in the pantry 12 additionally increased.

Furthermore, on the pressure piston 8th or the housing 9 sealing elements 26 be provided, which abut both components and leakage between tween the pressure chambers 12 . 13 and between the control room 13 and the backpressure room 21 minimize.

1

hydraulic system

2

accumulator

3

consumer

4

Pressure medium line

5a, b, c

check valve

6

tank

7

Hydraulic pump

8th

pressure piston

9

casing

10

first print area

11

second print area

12

pantry

13

control room

14

attack

15

supply line

16

control line

17

control means

18

way valve

19

vent

20

connecting line

21

Counterpressure chamber

22

third print area

23

spring element

24 25

Pressure medium connection

26

sealing element

P

pressure connection

T

drain connection

A

Control space connection

G

Back pressure port

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 4202905 A1 [0003]

Claims (12)

Accumulator ( 2 ) with a housing ( 9 ), one inside the housing ( 9 ) arranged displaceable element ( 10 ) and an energy store ( 23 ), Wherein the displaceable element ( 8th ) a first printing surface ( 10 ), wherein the first pressure surface ( 10 ) and the housing ( 9 ) a storeroom ( 12 ) at least partially and • wherein the displaceable element ( 8th ) by pressurizing the storage space ( 12 ) against the force of the energy store ( 23 ), characterized in that • the displaceable element ( 8th ) a second printing surface ( 11 ), wherein the second printing surface ( 11 ) and the housing ( 9 ) a control room ( 13 ) at least partially, • whereby the displaceable element ( 8th ) by pressurizing the control room ( 13 ) also against the force of the energy storage ( 23 ) and • where the accumulator ( 2 ) is designed such that a pressure medium flow within the pressure accumulator ( 2 ) between the control room ( 13 ) and the storage room ( 12 ) at least in the direction of the control room ( 13 ) is locked or can be locked. Accumulator ( 2 ) according to claim 1, characterized in that the storage space ( 12 ) with a consumer ( 3 ) is connectable. Accumulator ( 2 ) according to claim 1, characterized in that the storage space ( 12 ) with a consumer ( 3 ) communicates. Accumulator ( 2 ) according to claim 1, characterized in that the control room ( 13 ) without pressure with a tank ( 6 ) can be connected. Accumulator ( 2 ) according to claim 1, characterized in that the control room ( 13 ) without pressure with a tank ( 6 ) can be connected, without at the same time the pantry ( 12 ) with the tank ( 6 ) communicates Accumulator ( 2 ) according to claim 1, characterized in that the control room ( 13 ) independent of the storage room ( 12 ) can be emptied. Accumulator ( 2 ) according to claim 1, characterized in that the control room ( 13 ) optionally with a pressure source ( 7 ) or a tank ( 6 ) can be connected. Accumulator ( 2 ) according to claim 7, characterized in that control means ( 17 ) are provided, wherein the control room ( 13 ) by means of the control means ( 17 ) optionally with a tank ( 6 ) or a pressure source ( 7 ) can be connected. Accumulator ( 2 ) according to claim 1, characterized in that a pressure medium loading of the storage space ( 12 ) the displaceable element ( 8th ) is displaced in the same direction as a pressurization of the control room ( 13 ). Accumulator ( 2 ) according to claim 1, characterized in that the displaceable element ( 8th ) a third printing surface ( 22 ) having a counterpressure space ( 21 ) is at least partially limited, wherein a pressure medium loading of the back pressure chamber ( 21 ) the displaceable element ( 8th ) is displaced in the opposite direction as a pressurizing of the control chamber ( 13 ) or the storage room ( 12 ). Accumulator ( 2 ) according to claim 1, characterized in that the storage space ( 12 ) with a consumer ( 3 ) is at least connectable, the control room ( 13 ) with a tank ( 6 ) and the ratio between the minimum flow area between the control space ( 13 ) and the tank ( 6 ) and the minimum flow area between the reservoir ( 12 ) and the consumer ( 3 ) is greater than the ratio between the area of the second printing surface ( 11 ) and the area of the first printing surface ( 10 ). Accumulator ( 2 ) according to claim 1, characterized in that the storage space ( 12 ) and the control room ( 13 ) within the accumulator ( 2 ) do not communicate with each other.