The present invention relates to a fluid manifold. More specifically, this invention relates to a fluid manifold and a hydraulic accumulator.
Fluid manifolds are well known and may act as connection devices for fluid components. For example, fluid manifolds may be used in fluid systems and may act to provide a connection device between and among fluid components of the fluid system. The fluid components that are connected by the manifold may for example include a component source of fluid energy and a component recipient of fluid energy or multiple such components. The component source of fluid energy may for example include a fluid pump or a fluid pressure storage device. The component recipient of fluid energy may for example include a fluid valve, a fluid motor, and/or another fluid pressure storage device.
Accumulators are also well known and act as storage devices for storing energy in the form of fluid under pressure. For example, hydraulic fluid accumulators may store hydraulic fluid under pressure for use by other fluid components. Since hydraulic fluid is non-compressible, hydraulic accumulators may include a pressurization source for acting upon the stored hydraulic fluid. Known pressurization sources for hydraulic accumulators include for example springs, a weight that is acted upon by gravity, or a charged gas (or gas under pressure) such as compressed air. Charged gas is the most commonly used pressurization source for hydraulic accumulators There are two main types of charged gas hydraulic accumulators; a bladder accumulator and a piston accumulator. In a bladder accumulator, the interior of the accumulator body or shell is divided by an expandable bladder or diaphragm into two chambers. Hydraulic fluid is received in and stored in one of the chambers, while the charged gas is received in and stored in the other chamber. In many bladder accumulators, the expandable bladder is shaped like a balloon with an opening to the interior of the bladder fixedly supported relative to one end of the accumulator body. In piston accumulators, a floating piston located within and sealing against the accumulator body defines a boundary between the two chambers of the accumulator. The charged gas acts upon one side of the floating piston to apply a force to the hydraulic fluid that is located on an opposite side of the floating piston. In both bladder and piston accumulators, aligning, connecting and disconnecting multiple fluid components or conduits to and from the accumulator when installing or exchanging or servicing the accumulator can, at times, be difficult and/or labor intensive, particularly when the accumulator is large and heavy and is fixed in place relative to another structure.
At least one embodiment of the invention provides a a fluid manifold and a fluid manifold in combination with a fluid component. The fluid component may be a charged gas chamber of a hydraulic accumulator. The manifold may include multiple fluid ports and a single point rotatable connection for connecting the manifold multiple ports to the accumulator. The fluid manifold may provide a connection for the charged gas source to the charged gas chamber and may be rotated through 360 degrees about a longitudinal axis of the accumulator. The rotatable gas manifold may simplify installation of the accumulator by enabling its associated fluid components and/or conduits to be easily aligned with, connected to and disconnected from the accumulator. Thus, when large accumulators are installed in a system, the accumulators may be fixed in place relative to their support structure without the need to align or realign the other fluid components and/or conduits associated with the charged gas side of the accumulator.
The invention further provides a fluid manifold for use with a fluid component that includes a fluid component fluid port. The fluid manifold may include a body and a locking connector. The body may have a plurality of manifold individual fluid ports and a manifold common fluid port. Passages in the body may establish fluid communication between the manifold individual fluid ports and the manifold common fluid port. The locking connector may have a locking surface for attaching the manifold body to the fluid component, with the manifold common fluid port in fluid communication with the fluid component fluid port. The body may be rotatable relative to the locking connector.
The locking connector may include a fluid flow path. The locking connector fluid flow path may be in fluid communication with the manifold common fluid port. The manifold common fluid port may be annular, and the locking connector may extend longitudinally through the annular manifold common fluid port.
The manifold common fluid port may be defined between the body and the locking connector. The body may include a longitudinally extending opening, and the locking connector may be disposed in the opening. The manifold common fluid port may be disposed along the opening. The manifold common fluid port may include an annular groove disposed along the opening. The manifold individual fluid ports may extend radially from the opening.
The locking connector may include a fluid passage, and the fluid passage in the locking connector may include a longitudinally extending passage and a radially extending passage. The radially extending passage may be in fluid communication with the manifold common fluid port and with the longitudinally extending passage. The locking connector may include a stem, and the longitudinally extending passage and the radially extending passage may be disposed in the stem. The locking surface of the locking connector may include a threaded portion on an exterior surface of the stem, and the longitudinally extending passage may be disposed radially inwardly of the threaded portion. The locking connector may include a head, and the head may engage the body.
Annular seals may be disposed between the stem and the opening on longitudinally opposite sides of the passages in the body that extend from the individual fluid ports to the common fluid port. The annular seals may be disposed on longitudinally opposite sides of the radial passage in the stem. The locking connector may be rotatable relative to the body, and the radial passage in the stem may be in fluid communication with the common manifold fluid port in all rotatable positions of the manifold relative to the body. The locking connector is rotatable through 360 degrees relative to the body.
The fluid manifold may be arranged in combination with a fluid component, and the fluid component may be a hydraulic accumulator. The hydraulic accumulator may have a longitudinal axis, the body may have a longitudinal axis, and the axes may be co-axial. The hydraulic accumulator may include a shell having first and second ends and defining an interior volume, and a movable member may divide the interior volume into two variable volume chambers each of which includes an associated opening. One chamber may be adapted to receive a non-compressible fluid and the other chamber may be adapted to receive a charged gas. A closure assembly may close the opening to the charged gas chamber, and the closure assembly may include the fluid component port. The locking connector may removable attach the body to the closure assembly.
The locking connector may include a lock bolt having a stem portion through which a central fluid connector passage extends, and a plurality of radial passages may extend through the stem portion and interconnect with the central fluid connector passage. The lock bolt may further include a plurality of annular grooves, and each annular groove may receive an annular elastomeric seal. At least one of the annular grooves may be located between the plurality of radial passages and the head portion of the lock bolt. At least one of the annular grooves may be located between the plurality of radial passages and a threaded portion of the lock bolt.
The invention also provides various ones of the features and structures described the claims set out below, alone and in combination, and the claims are incorporated by reference in this summary of the invention
Embodiments of this invention will now be described in further detail with reference to the accompanying drawings, in which:
Referring now to the drawings in greater detail, the principles, embodiments and operation of the present invention are shown in the accompanying drawings and described in detail herein. These drawings and this description are not to be construed as being limited to the particular illustrative forms of the invention disclosed. It will thus become apparent to those skilled in the art that various modifications of the embodiments herein can be made without departing from the spirit or scope of the invention.
The accumulator 10 and gas manifold 12 are longitudinally co-axial along a longitudinal axis 14. The accumulator 10 includes a shell 16 that defines an interior volume. The shell 16 may be made of any suitable material for containing fluid under pressure. In one embodiment, the shell 16 is made from steel. In the embodiment illustrated in the drawings, the shell 16 is made from a suitable carbon fiber and resin composite material. A liner 18 is attached to the shell 16. The liner 18 is of any suitable material, and in the preferred embodiment the liner 18 is of a high density polyethylene material. The shell 16 has opposite first and second ends 26 and 28. As further described below, the first end 26 provides a hydraulic fluid pressure end of the accumulator 10, and the second side 28 provides a charged gas end of the accumulator 10. The end 26 includes a hydraulic fluid pressure annular end piece 30, and the end 28 includes a charged gas annular end piece 32. The hydraulic fluid pressure end piece 30 has a threaded interior surface that defines an opening. The liner 18 is attached to the end pieces 30 and 32 and prevents fluid escape from the shell 16.
The opening of the shell 16 at the hydraulic fluid pressure end 26 is closed by a first end closure assembly 36, illustrated as a port block assembly that is threadedly inserted into the threaded interior surface of the end piece 30. The illustrated port block assembly 36 includes a spring 38 that biases a valve poppet 40 toward an opened position. As described further below, the port block assembly 36 is adapted to enable flow of hydraulic fluid into and out of a variable volume defined inside the liner 18 of the shell 16. The opening of the shell 16 at the second end 28 is closed by a second end closure assembly 44 that is joined to the end piece 32 by a clearance fit. The second closure assembly 44 illustrated is adapted to support an open end portion 50 of an expandable bladder 52 and to provide a component fluid port that enables a flow of the charged gas into and out of the interior of the supported bladder 52. The bladder 52 is of any suitable elastomeric polymeric material, and in the preferred embodiment the bladder 52 is of low temperature nitrile material. The bladder 52 divides the volume of the shell 16 into two variable volume chambers. As illustrated in
As is known in the art, the bladder 52 is filled with a charged gas, typically to a predetermined charge pressure, and remains under pressure during operation of the accumulator 10. As hydraulic fluid enters chamber 58 to store energy as fluid under pressure, for example when the above described vehicle is decelerating, the charged gas in the bladder 52 is compressed. During this mode of operation, the volume of the hydraulic fluid chamber 58 expands and the volume of the charged gas chamber 56 and bladder 52 contract in size. The charged gas in the chamber 56 maintains the pressure of the stored hydraulic fluid in the chamber 58. When the energy stored in the hydraulic fluid is to be used during another mode of operation, the hydraulic fluid exits from the chamber 58. During this mode of operation, the volume of the charged gas chamber 56 and bladder 52 expands to reduce the pressure of the charged gas in the bladder back to the charge pressure and the volume of the hydraulic fluid chamber 58 decreases. When the bladder 52 expands a sufficient distance so as to close the poppet 40, further fluid flow from the chamber 58 is prevented.
In this manner, the end piece 30 provides access for hydraulic fluid flow to and from the hydraulic fluid chamber 58 of the accumulator 10 defined between the liner 18 and the bladder 52. The end piece 32 provides access for charge gas into the charged gas chamber 56 of the accumulator 10 inside the bladder 52. Due to the repeated expansion and contraction of the bladder 52 during operation, which may occur at high and low operating temperature extremes, the accumulator 10 may be periodically removed and replaced during servicing of the hydraulic system in which the accumulator 10 is used. The manifold 12 facilitates this removal and replacement, as further described below.
Referring now to
The second closure assembly 44 further includes a bottom or longitudinally inner gas plug 84 and a top or longitudinally outer gas plug 86. The top gas plug 86 is joined by a clearance fit to the end piece 32 so that a head portion 88 of the top gas plug 86 abuts against an end surface of the end piece 32. The bottom gas plug 84 supports an anti-extrusion ring 94 and, when the second closure assembly 44 is assembled, abuts against the top gas plug 86. The bladder 52 includes the open end portion 50 that is received by the head portion 74 of the fluid component port member 70 so as to align an opening in the bladder 52 with the fluid passage or port 72 in the fluid component port member 70. In the assembled second closure assembly 44, the opened portion 50 of the bladder 52 is held securely between the head portion 74 of the fluid component port member 70 and the bottom gas plug 84 by a tension created by tightening a jam nut 96 on the threaded portion 76 of the stem member such that the jam nut 96 abuts against the top gas plug 86.
Referring now to
Continuing with reference to
The gas manifold 12 also includes a generally cylindrical locking connector 150, which is in the general shape of a lock bolt and provides a single point mechanical and fluid connection for the manifold 12 with the accumulator 10. The locking connector 150 is rotatable through 360 degrees relative to the body 102. In the preferred embodiment, the locking connector 150 has a stepped exterior surface and includes a locking connector stem portion 152 and a locking connector head portion 154. The head portion 154 provides a wrench receiving exterior surface and has a larger diameter than the stem portion 152. The head portion 154 is recessed into an enlarged diameter portion of the main opening 104 and engages the main body 102. The stem portion 152 extends from the head portion 154 into and along the opening or passage 104 of the manifold body 102 and terminates with a smaller diameter portion 160 having a threaded exterior surface. The smaller diameter threaded portion 160 is adapted to be threadedly received in the passage 72 of the fluid component port member 70 for affixing the gas manifold 12 to the second closure assembly 44 of the fluid component or accumulator 10 with a single point connection. In an alternative embodiment not shown in the drawings, the head portion 154 could be formed as a flange that is connected to the main body 102 by two or more bolts that are separate from the stem portion 152 while the stem portion 152 and the annular groove 142 maintain the single point fluid connection of the manifold 12 to the accumulator 10.
An intermediate generally cylindrical exterior portion 164 of the locking connector 150 is located on the stem portion 152 between the smaller diameter portion 160 and the head portion 154. A plurality of radial passages 180, two of which are illustrated in
When the gas manifold 12 is mounted to the second closure assembly 44 of the fluid component 10, the locking connector 150 is disposed in the opening 104 in the body 102 and is threadedly connected to the port member 70. A washer 200 is positioned between the head portion 154 of the lock bolt 150 and the main body 102 and, as the lock bolt 150 is tightened, the head portion 154 presses the main body 102 of the gas manifold 12 against the fluid component port member 70 for fixing the gas manifold relative to the accumulator 10. At least one radial passage 180 in the lock bolt 150 aligns with each of the passages 140 or its associated groove 142 in the main body 102 such that the charged gas may pass through the ports to the radial passages 180 and central passage 182 to the passage or port 72 of the fluid component port member 70 and into the bladder 52 through opening. Should a position of the main body 102 need to be rotated, for example, so as to align valve assembly 126 with an associated conduit, the lock bolt 150 may be loosened and the body 102 rotated to its appropriate position. Once the body 102 is rotated to its appropriate position, the lock bolt 150 again is tightened for affixing the gas manifold 12 relative to the fluid component port member 70. Again, radial passages 180 in the lock bolt 150 align with the ports in the main body 102 of the gas manifold 12. The gas manifold 12 enables alignment of the various ports and associated valves without the need to disassemble the accumulator 10, particularly the second closure assembly 44 of the accumulator 10.
Presently preferred embodiments of the invention are shown and described in detail above. The invention is not, however, limited to these specific embodiments. Various changes and modifications can be made to this invention without departing from its teachings, and the scope of this invention is defined by the claims set out below. For example, instead of having a bladder 52, the accumulator 10 may be a piston accumulator. Such improvements, changes and modifications within the skill of the art are intended to be covered by the appended claims. Also, while the terms first and second, one and another, left and right are used to more clearly describe the structure and operation of the manifold 12 and accumulator 10, it should be understood these terms are used only for purposes of clarity and may be interchanged as appropriate.
Although the principles, embodiments and operation of the present invention have been described in detail herein, this is not to be construed as being limited to the particular illustrative forms disclosed. They will thus become apparent to those skilled in the art that various modifications of the embodiments herein can be made without departing from the spirit or scope of the invention.
The present application claims the benefit of the filing date of U.S. Provisional Patent Application Ser. No. 61/374,831, flied Aug. 18, 2010, the disclosure of which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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61374831 | Aug 2010 | US |