U.S. patent application number 09/935762 was filed with the patent office on 2002-05-16 for hydraulic accumulator.
This patent application is currently assigned to Hydac Technology GmbH. Invention is credited to Weber, Norbert.
Application Number | 20020056275 09/935762 |
Document ID | / |
Family ID | 7664117 |
Filed Date | 2002-05-16 |
United States Patent
Application |
20020056275 |
Kind Code |
A1 |
Weber, Norbert |
May 16, 2002 |
Hydraulic accumulator
Abstract
A hydraulic accumulator, particularly a floating piston
accumulator, has a housing containing at least one gas chamber and
one fluid chamber. The chambers are separated from one another by a
barrier element. One of the chambers can be filled with a pressure
medium or can be at least partially emptied through a controlling
valve assembly having at least one control valve. The controlling
valve assembly is an integral component part of the housing, is
attached at an end to the housing and is configured as a solid
control block. The control block includes the control valve. A
costly network of lines between the hydraulic accumulator and the
controlling valve assembly is avoided and sealing or leakage
problems customary in networks of lines can be totally avoided.
Inventors: |
Weber, Norbert;
(Sulzbach/Saar, DE) |
Correspondence
Address: |
Mark S. Bicks
Roylance, Abrams, Berdo & Goodman, L.L.P.
Suite 600
1300 19th Street, N.W.
Washington
DC
20036
US
|
Assignee: |
Hydac Technology GmbH
|
Family ID: |
7664117 |
Appl. No.: |
09/935762 |
Filed: |
August 24, 2001 |
Current U.S.
Class: |
60/413 |
Current CPC
Class: |
F15B 2201/205 20130101;
F15B 2201/31 20130101; F15B 2013/004 20130101; F15B 1/24 20130101;
F15B 2201/4155 20130101; F15B 1/22 20130101; F15B 2201/411
20130101; F15B 1/033 20130101; Y10T 137/7792 20150401 |
Class at
Publication: |
60/413 |
International
Class: |
F16D 031/02 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 16, 2000 |
DE |
100 57 746.6 |
Claims
What is claimed is:
1. A hydraulic accumulator, comprising: a housing having at least
one gas chamber and at least one fluid chamber therein; a barrier
element in said housing separating said gas and fluid chambers; and
a controlling valve assembly attached at one end of said housing as
an integral component part thereof, said controlling valve assembly
including a solid control block and a first control valve located
in said control block, said first control valve being in fluid
communication with and controlling the flow of a pressure medium
into and out of one of said chambers.
2. A hydraulic accumulator according to claim 1 wherein said
barrier element is a floating piston.
3. A hydraulic accumulator according to claim 1 wherein said
control block comprises an appendix part engaging an inside surface
of said housing and an offset section at a beginning of said
appendix part engaging an open end of said housing.
4. A hydraulic accumulator according to claim 3 wherein said
appendix part defines one end of said fluid chamber; and said
control block comprises at least one fluid passage with one open
end thereof opening with another open end thereof coupled to said
control valve.
5. A hydraulic accumulator according to claim 4 wherein said
controlling valve assembly comprises a second control valve in said
control block adjacent said first control valve.
6. A hydraulic accumulator according to claim 5 wherein said second
control valve is in fluid communication with said gas chamber for
controlling flow of working gas into and out of said gas chamber to
control pressure therein.
7. A hydraulic accumulator according to claim 6 wherein said gas
chamber comprises an additional fluid chamber and controls a
different structural group in a hydraulic circuit.
8. A hydraulic accumulator according to claim 5 wherein each of
said control valves comprise a 2/2-way valve.
9. A hydraulic accumulator according to claim 1 wherein said first
control valve comprises a 2/2-way valve.
10. A hydraulic accumulator according to claim 9 wherein said
2/2-way valve is an electrically controlled magnet valve.
11. A hydraulic accumulator according to claim 8 wherein said
2/2-way valves are electrically controlled magnet valves.
12. A hydraulic accumulator according to claim 1 wherein said
housing and said control block are essentially cylindrical.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a hydraulic reservoir or
accumulator, particularly a piston or floating piston accumulator,
having a housing with at least one gas chamber and one fluid
chamber arranged therein. The chambers are separated from one
another by a barrier element. At least one chamber can be filled
with a pressure medium through a controlling valve assembly
including at least one control valve or can be at least partially
emptied using that control valve.
BACKGROUND OF THE INVENTION
[0002] One of the main purposes of hydraulic accumulators is to
retain certain volumes of fluid making up a hydraulic system under
pressure, and, when the fluid is called back, to feed this fluid
back into the system under pressure. Hence traditional floating
piston accumulators, dissolved gas-drive bubble accumulators, or
diaphragm accumulators are considered as hydraulic accumulators.
Weight-biased and spring-biased accumulators can be included in
this group. A plurality of objectives can be realized with such
hydraulic accumulators, such as energy storage, impact absorption,
shock absorption, vibration absorption, pulsation absorption,
energy recovery, flow volume compensation and so forth.
[0003] Controlling valve assemblies can be used for the operation
and control of the hydraulic accumulator. Such valve units are
traditionally provided with switching or multi-way valves for the
generation of the fluid current from and to the hydraulic
accumulator. The hydraulic accumulator is hence normally attached
to a tubing or conduit system having fluid-conveying lines, which
produce the fluid-conveying connection or fluid communication
between the accumulator and the controlling valve assembly.
[0004] Drawbacks of such a known accumulator, which can obviously
be attained in a number of different embodiments presently on the
market, reside in the form of sealing problems arising as a result
of the increased number of connections between hydraulic
accumulator conduit systems and controlling valve assemblies, and
can also be seen in the additional costs for the network of
conduits serving as fluid lines. Particularly with construction
relationships and systems of narrow dimensions, problems can arise
involving the accommodation of the great plurality of these
components and connecting them with one another so that they will
be in fluid communication. Since various manufacturers are
responsible for manufacturing hydraulic accumulators, including the
conduit systems and/or the valves of the controlling valve
assembly, difficulties of adaptation and fitting of the parts arise
particularly at the site of the construction.
SUMMARY OF THE INVENTION
[0005] Objects of the present invention are to overcome these
drawbacks of conventional accumulators.
[0006] The foregoing objects are basically obtained by a hydraulic
accumulator, comprising a housing having at least one gas chamber
and at least one fluid chamber therein, a barrier element in the
housing separating the gas and fluid chambers, and a controlling
valve assembly attached at one end of said housing as a integral
component part thereof. The controlling valve assembly includes a
solid control block and a first control valve located in the
control block. The first control valve is in fluid communication
with and controls the flow of a pressure medium into and out of one
of the chambers.
[0007] Since the controlling valve assembly is an integral part of
the accumulator housing, attached at the end to the housing and
configured as a solid control block including essentially the
relevant control valve, the conventional costly network of lines
between the hydraulic accumulator and the controlling valve
assembly is avoided. The sealing or leakage problems, as customary
in networks of lines, quite certainly cannot occur at all.
Manufacture and installation costs for the hydraulic accumulator
are considerably reduced by avoiding the use of fluid lines. Tying
in of the controlling valve assembly as an integral component part
of the hydraulic accumulator allows for very tight construction
dimensions. Even with limited availability of construction
dimensions in vehicles or in buildings, such as within mechanical
installations, suitable installations can still be undertaken.
Since the controlling valve assembly is aligned directly as the
control block on the hydraulic accumulator, the controlling valve
assembly can also work directly on the accumulator, so that the
accumulator function has extraordinarily short reaction times and
fluid volumes can be carried in and out of the accumulator chambers
in the shortest time possible. The solution according to the
present invention reduces or entirely prevents loss of pressure
between valve and hydraulic accumulator (the user).
[0008] In one particularly preferred embodiment of the hydraulic
accumulator of the present invention, the control block engages
with its appendix part in flush contact with the interior periphery
inside the accumulator housing. The accumulator housing with its
one open end engages on a setoff section of the control block, at
which the appendix part begins. Secure sealing of the connection
between accumulator housing and control block appendix part can be
attained as a result of this configuration. Furthermore, through
the setoff section, precise contact of the accumulator housing with
the control block is possible and the accumulator housing is guided
precisely along the appendix part of the control block. Undesirable
separation of accumulator housing from controlling valve assembly
is thus absolutely avoided.
[0009] In the case of another preferred embodiment of the hydraulic
accumulator of the present invention, the control block with its
appendix part limits the fluid chamber. The control block then has
at least one fluid passage with its one open end opening into the
fluid chamber and with its other open end attached to the control
valve. Since the control block fits directly into the fluid
chamber, the open multi-way passages for the pressure medium are of
limited dimensions, providing rapid reaction times for the
hydraulic accumulator.
[0010] With one particularly preferred embodiment of the hydraulic
accumulator of the present invention, at least one further control
valve, in addition to the first control valve, is present in the
control block. This additional control valve can be connected in
fluid communication with the gas chamber, and can control the inlet
and discharge of working gas in the gas chamber. In the case of
another similar construction, the additional control valve can be
connected in fluid communication with and to act on a separate
structural group involving a hydraulic circuit to undertake control
of the fluid displacement.
[0011] Other objects, advantages and salient features of the
present invention will become apparent from the following detailed
description, which, taken in conjunction with the annexed drawing,
discloses a preferred embodiment of the present invention.
BRIEF DESCRIPTION OF THE DRAWING
[0012] Referring to the drawing which forms a part of this
disclosure:
[0013] FIG. 1 is a front elevational view, partially in section, of
a hydraulic accumulator according to an embodiment of the present
invention.
DETAILED DESCRIPTION OF THE INVENTION
[0014] The hydraulic accumulator shown in FIG. 1 is configured as a
floating piston accumulator or reservoir. This unit includes an
accumulator housing 10 with a gas chamber 12 and a fluid chamber 14
arranged therein. Gas chamber 12 is separated from the fluid
chamber 14 by a barrier element 16 in the form of a portion of a
piston. The piston is guided for longitudinal sliding movement
along the interior periphery of accumulator housing 10, so that the
ratio of the dimensions of gas chamber 12 to fluid chamber 14 is
variable. In order to be able to store a greater volume of gas to
be used as work gas in gas chamber 12, barrier element 16 is
configured as a hollow member. The interior of the barrier element
incorporates a suitable cutout 18 in its design.
[0015] When viewing gas chamber 12 as seen in the drawing, the top
is closed by a cover part 20. Chamber 12 is accessible through a
middle bore 22, through which a working gas, for instance nitrogen,
can be fed into gas chamber 12. Middle bore 22 is then sealed off
gas-tight by a shutoff valve or the like (not shown), whereby from
time to time the volume of gas in gas chamber 12 can be tested and
can be refilled through such shutoff valve.
[0016] The controlling valve assembly, indicated in its entirety as
26, is enclosed in a control block 24 at the opposite end of
reservoir housing 10 from cover part 20. Controlling valve assembly
26 houses a first control valve 28 and a second control valve 30.
The controlling valve assembly 26 is consequently an integral
component part of reservoir housing 10. For this purpose, control
block 24 is provided with a projection 32 engaged in flush contact
with the interior periphery inside reservoir housing 10.
Accumulator housing 10 engages with its one open end 34 on a setoff
section 36 of control block 24, at which the projection or appendix
part 32 begins. The other exterior diameter of control block 24, at
appendix part 32 engaged in reservoir housing 10, is consequently
reduced in diameter according to the degree of pulling back over
setoff section 36.
[0017] Control block 24 limits the bottom of fluid chamber 14 with
the top end of appendix part 32 extending upwardly from below as
seen in the drawing. Accumulator housing 10, chambers 12 and 14,
cover part 20, piston part 16 as well as appendix part 32 are
configured essentially as cylindrical structural parts and are
aligned along the common longitudinal axis 38 of the hydraulic
accumulator. Control block 24 furthermore has a fluid passage 40
arranged off-center to or laterally offset from longitudinal axis
38. One open end of passage 40 opens into fluid chamber 14. The
other open end of passage 40 is connected to the first control
valve 28. Transverse to fluid passage 40, a transverse connection
42 extends into control block 24, to which could potentially be
attached a fluid feed line, for example, as a component part of a
hydraulic circuit. Between transverse connection 42 and fluid
passage 40, first control valve 28 is mounted, whereby the
fluid-conveying connection between transverse connection 42 and
fluid passage 40 is opened in one switch setting and is blocked off
in the other switch setting.
[0018] Preferably, the first control valve 28 is configured as a
2/2-way valve. However, other valves could be used at this point in
the arrangement, such as multi-way-slide-valves, valves with
damping fixtures or the like, dependent upon the intended use.
[0019] In parallel construction and aligned in the same direction
as first control valve 28, another or second control valve 30 is
arranged and is also configured in the present case as a 2/2-way
valve. Second control valve 30 has two side connections 44 and 46,
extending from the valve in manners similar to the transverse
connection 42 in radial alignment on the side extending out from
control block 24. The two side connections 44 and 46 are in turn
separated from one another on the switch parts of second control
valve 30. With second control valve 30 connected through, the side
attachments 44 and 46 are connected with one another fluid-carrying
or in fluid communication, and then are separated from one another
when the valve is switched into a blocking setting. With such an
arrangement of second control valve 30, for example, according to
an embodiment which is not described herein in greater detail, the
inlet and discharge of the work gas in and out of gas chamber 12
can be controlled when connections 44 and 46 are coupled in fluid
communication through connection 60 to cover part 20 with gas
chamber 12. In another embodiment not described in greater detail,
second control valve 30 can control a different structural group 62
in the hydraulic circuit, for example in the form of a hydraulic
working cylinder or the like, through connection 64.
[0020] In the present embodiment, control valves 28 and 30 are
configured as magnet valves 48, which can be controlled
electrically through connections 50. Since such magnet valves 48
are the present state of the art or are conventional they will not
be discussed in greater detail.
[0021] The hydraulic accumulator of the present invention realizes
a complete solution of the problems addressed by the invention and
allows a compact structural embodiment. In the embodiment shown in
the drawing, first and second control valves 28 and 30 are
essentially axially parallel to longitudinal axis 38 of the
hydraulic accumulator arranged above the valves in control block
24. However, other structural layouts can be used, particularly a
radial layout transverse to longitudinal axis 38. Because of the
flush connection of reservoir housing 10 to control block 24,
leakage is avoided and a costly system of tubing can also be
avoided. Since control block 24 engages directly with its appendix
part 32 in fluid chamber 14 of accumulator housing 10, particularly
the first control valve 28 is arranged directly in the vicinity of
fluid chamber 14, and is separated therefrom only by the fluid
passage 40 which is of short structural length, so that the
hydraulic accumulator can be actuated with very short control
reaction delays.
[0022] While one embodiment has been chosen to illustrate the
invention, it will be understood by those skilled in the art that
various changes and modifications can be made therein without
departing from the scope of the invention as defined in the
appended claims.
* * * * *