EP1481168B1 - Multi-function hydraulic valve assembly - Google Patents
Multi-function hydraulic valve assembly Download PDFInfo
- Publication number
- EP1481168B1 EP1481168B1 EP20030701411 EP03701411A EP1481168B1 EP 1481168 B1 EP1481168 B1 EP 1481168B1 EP 20030701411 EP20030701411 EP 20030701411 EP 03701411 A EP03701411 A EP 03701411A EP 1481168 B1 EP1481168 B1 EP 1481168B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- operator
- valve
- hydraulic
- port
- assembly
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/12—Platforms; Forks; Other load supporting or gripping members
- B66F9/14—Platforms; Forks; Other load supporting or gripping members laterally movable, e.g. swingable, for slewing or transverse movements
- B66F9/142—Movements of forks either individually or relative to each other
- B66F9/143—Movements of forks relative to each other - symmetric
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/12—Platforms; Forks; Other load supporting or gripping members
- B66F9/14—Platforms; Forks; Other load supporting or gripping members laterally movable, e.g. swingable, for slewing or transverse movements
- B66F9/147—Whole unit including fork support moves relative to mast
- B66F9/148—Whole unit including fork support moves sideways
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/20—Means for actuating or controlling masts, platforms, or forks
- B66F9/22—Hydraulic devices or systems
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/20—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors controlling several interacting or sequentially-operating members
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
- F15B13/07—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors in distinct sequence
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/2496—Self-proportioning or correlating systems
- Y10T137/2544—Supply and exhaust type
- Y10T137/2554—Reversing or 4-way valve systems
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8593—Systems
- Y10T137/86493—Multi-way valve unit
- Y10T137/86574—Supply and exhaust
- Y10T137/8667—Reciprocating valve
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8593—Systems
- Y10T137/86493—Multi-way valve unit
- Y10T137/86574—Supply and exhaust
- Y10T137/8667—Reciprocating valve
- Y10T137/86694—Piston valve
- Y10T137/8671—With annular passage [e.g., spool]
Definitions
- the invention is related to hydraulic systems, and in particular, to a multi-function hydraulic valve assembly.
- hydraulic systems for moving or lifting loads.
- such systems utilize hydraulic fluid under pressure to drive hydraulic operators, such as piston/cylinder arrangements.
- a piece of machinery, such as a hoist or a truck may require several hydraulic operators to move the load in different ways.
- the various hydraulic operators are each controlled by a lever located in the cab of the machine or vehicle.
- One example where hydraulic systems are used in this way are lift trucks.
- Lift trucks are vehicles which are used to pick up and move loads from place to place.
- a conventional lift truck includes a carriage which supports a pair of forks. The forks are maneuvered into place by the lift truck operator and are used to pick up the load.
- the carriage rides vertically in a mast, which also supports the carriage. In addition the mast may be tilted backward to facilitate stabilizing the load on the forks.
- Two separate hydraulic operators are used to move the carriage vertically and to tilt the mast.
- a side shift assembly which facilitates aligning the spaced pair of forks with the load.
- side shifting is used io describe the concept of shifting the forks as a spaced pair either left or right of the vehicle center line. This function provides the operator with a greater margin for error when aligning the vehicle with the load.
- a hydraulic operator such as a piston/cylinder arrangement is typically used by the side shifting assembly to move a frame to which the forks are secured.
- a fork positioning assembly Another attachment to enhance the capability of a lift truck is a fork positioning assembly.
- the term fork positioning is used to describe the concept of changing the relative spacing between the forks to accommodate loads of different widths.
- a hydraulic operator such as a piston/cylinder arrangement is used in the fork positioning assembly to move the forks.
- a cab of a conventional lift truck provides three levers to operate three hydraulic operators. Accordingly, if a user requires four hydraulic operators, such as, for example, by installing a fork positioning attachment, an additional lever must be installed to operate the fork positioning attachment.
- prior art systems such as US-A-5 139 385 permit operation of two separate hydraulic operators with a single lever on a lift truck. These systems utilize an electrical circuit to toggle between the two hydraulic operators. Prior to moving the lever which actuates the hydraulic system, the user would activate the electrical switch to select the appropriate hydraulic operator. This system adds expense and complexity to the design of the lift truck. In addition, electrical cables must be provided and extended over the lift truck mast.
- FR2720123 discloses an automated hydraulic control for use in ploughs.
- the present invention relates to a hydraulic valve assembly as set out in claim 1.
- Figure 1 is a schematic of a hydraulic system for a lift truck
- Figure 2 is a perspective view of a valve assembly according to a preferred embodiment of the present invention.
- Figure 3 is a cross-sectional view of a valve block for the preferred embodiment of Figure 2 ;
- Figure 4 is a perspective view of a selection valve for the preferred embodiment of Figure 2 ;
- Figure 5A is a cross-sectional view of the preferred embodiment of Figure 2 in a first position showing fluid flow in one direction;
- Figure 5B is a cross-sectional view of the preferred embodiment in the first position as shown in Figure 5A , but showing fluid flow in an opposite direction;
- Figure 5C is a cross-sectional view of the preferred embodiment of Figure 2 in a second position showing fluid flow in one direction;
- Figure 5D is a cross-sectional view of the preferred embodiment in the second position, as shown in Figure 5C , but showing fluid flow in the opposite direction;
- Figure 6 is a schematic view showing the preferred embodiment of Figure 2 connected to a side shifter and fork positioner.
- FIG. 1 shows a hydraulic system for a lift truck connected to a valve assembly 10 according to a preferred embodiment of the present invention.
- the valve assembly 10 is connected to a control panel 11 by a first hydraulic supply line 12 and a second hydraulic supply line 14.
- the control panel 11 is connected to a hydraulic fluid tank 16 by a tank supply line 18 and a tank return line 20.
- a pump (not shown) is connected to the tank supply line 18 to provide the hydraulic fluid under pressure.
- control panel 11 includes a hydraulic circuit 26 to interchangeably connect the tank supply and return lines 18, 20 to the first and second hydraulic supply lines 12 and 14.
- the circuit 26 is operated in a conventional manner and will not be further described.
- the circuit 26 is hydraulically connected to three corresponding levers in the lift truck cab. Other similar circuits may be used to control other vehicle functions such as mast tilting, carriage raising, and the like. For convenience, only the lever 28 for operating the particular circuit 26 is shown. It will be understood by those skilled in the art that other types of actuators may be provided.
- the valve assembly includes a valve block 30, which preferably has a box-like shape.
- a first supply port 32 and a second supply port 34 are provided in the valve block 30.
- the first and second supply ports 32, 34 communicate with first and second hydraulic supply lines 12, 14 (shown in Figure 1 ), respectively.
- the supply ports 32, 34 are located on the same face of the block 30.
- An orifice valve 35 (shown in Figures 5A-5D ) is preferably provided between the supply ports 32 and 34. The function of this orifice valve is discussed below.
- the diameter of the orifice valve may be about 1.09mm (0.043 inches).
- a first chamber 36 and a second chamber 38 are provided in the valve block 30.
- the first and second chambers 36, 38 communicate with first and second supply ports 32, 34 via first and second block channels 40 and 42.
- a first operator port 44 and a second operator port 46 are provided on one face of the block 30, and a third operator port 48 and a fourth operator port 50 are provided on the opposite face of the block 30.
- the first and second operator ports 44, 46 communicate with the first chamber 36.
- the third and fourth operator ports 48, 50 communicate with the second chamber 38.
- the first and third operator ports 44, 48 are connected to corresponding ports (not shown) of a first conventional hydraulic operator 80.
- the first hydraulic operator may be, for example, a fork positioning cylinder.
- the second and fourth operator ports 46, 50 are connected to corresponding ports (not shown) of a second hydraulic operator 82.
- the second hydraulic operator may be, for example, a side shifting cylinder.
- a pilot channel 52 is provided in the valve block 30.
- the pilot channel 52 communicates with first and second chambers 36, 38.
- the pilot channel 52 also communicates with first and second block channels 40, 42, all three meeting at an intersection 54.
- a bi-directional valve 56 is located in the intersection 54.
- the bi-directional valve is a conventional ball and shuttle valve. The bi-directional valve alternatively connects pilot channel 52 with block channel 40 or block channel 42.
- a first conventional selection valve 60 is located in the first chamber 36 and a second conventional selection valve 61 is located in the second chamber 38.
- the selection valves 60, 61 are identical.
- such valves are commercially available from various valve manufacturers.
- One useful example is a valve sold by Hydraforce Inc. (Model No. PD 10-40).
- the first selection valve 60 includes a generally cylindrical valve housing 62 mounted in the first chamber 36.
- the cylindrical valve housing 62 has an open end proximate to the pilot channel 52, and defines an internal valve chamber 64.
- the cylindrical valve housing 62 also includes a plurality of radially directed circumferentially arranged openings 65 for communicating with the first chamber 36.
- a moving valve body 66 is located within the valve chamber 64 of valve housing 62.
- the valve body 66 has a pressure surface 68 adjacent the open end of the valve housing 62.
- the valve body 66 has a narrower portion which defines an annular space 69.
- the radially directed openings 65 communicate with the annular space 69 between the valve body 66 and the valve housing 62.
- the valve body 66 is connected to a spring 74 located in a closed end of the cylindrical valve housing 62.
- Valve body 66 may be moved relative to valve housing 62 by collapsing the spring 74.
- the spring 74 biases the valve body 66 to the position shown in Figures 5A and 5B .
- the spring resistance is configured such that a pressure of 2.17 MPa (315 PSI) or greater applied to pressure surface 68 is required to collapse the spring 74 so that the valve body 66 may move to the position shown in Figures 5C and 5D .
- a number of external O-rings 70, 72 are provided to seal portions of the first selection valve 60 against portions of the wall of the first chamber 36.
- Internal O-rings (not shown) are also provided to seal the upper and lower ends of the annular space 69 from the remainder of the valve chamber 64 to prevent bleeding of fluid between the valve body 66 and valve housing 62.
- the second selection valve 61 is the same as the first selection valve 60, it will not be described in detail.
- valve assembly 10 For convenience, the operation of the present invention will be described in conjunction with a conventional hydraulically-operated fork positioner 80 and side shifter 82 for a lift truck.
- the first hydraulic operator will be the fork positioner
- the second hydraulic operator will be the side shifter.
- the present invention may be operated with any two hydraulic operators requiring different pressure, and is not confined to fork positioners and side shifters, or to hydraulic operators for lift trucks. The operators could be used for any desired function, such as rotating, tilting, clamping, or the like.
- the lift truck operator when the lift truck operator wishes to actuate the fork positioner in a first direction, such as to narrow the forks, the operator moves the lever 28 part-way in one direction.
- the circuit 26 is partially activated to supply hydraulic fluid from the hydraulic fluid tank 16 along tank supply line 18, through section 22, and then to the first hydraulic supply line 12. Because, the circuit 26 is only, parity activated, the flow rate of hydraulic fluid in the first hydraulic supply line 12 is low, resulting in low pressure as explained below.
- low pressure means pressure below 2.17 MPa (315 PSI).
- the hydraulic fluid enters the first supply port 32 and flows into first channel 40.
- the pressure of the fluid in first block channel 40 moves the bi-directional valve 56 into a position permitting fluid communication between first block channel 40 and pilot channel 52, while sealing off communication between second block channel 42 and the pilot channel 52.
- the pressure of the fluid in the pilot channel 52 acts on the pressure surface 68 of each of the selection valves 60, 61. Because the pressure is below 2.17 MPa (315 PSI), neither of the valve bodies 66 of the selection valves 60, 61 move. Accordingly, the annular channels of selection valves 60 and 61 remain aligned with first operator port 44 and third operator port 48, respectively.
- the supply fluid in first block channel 40 also enters the annular space 69 through the radially directed openings 65 in the cylindrical housing 62 of the first selection valve 60.
- the fluid exits from the annular space 69 of first selection valve 60 through additional radially directed openings 65 and enters first operator port 44.
- the fluid is prevented from entering second operator port 46 by O-ring 70 and the internal O-rings of the selection valve 60.
- the hydraulic fluid travels to the fork positioner 80 by line 84 connected to first operator port 44.
- hydraulic fluid also leaves the fork positioner 80 and enters third operator port 48 via line 86.
- the fluid is routed to second block channel 42 through the second selection valve 61, in a similar but reverse manner as described for first selection valve 60.
- the fluid exits the valve assembly 10 at second supply port 34 along second supply line 14.
- the operator moves the lever 28 part-way in the opposite direction causing the circuit 26 to partially activate so that section 24 is employed to direct a low pressure flow of fluid from the hydraulic fluid supply tank 16 into the second hydraulic supply line 14.
- the hydraulic fluid enters the valve block 30 via the second supply port 34 and into the second block channel 42.
- the bi-directional valve 56 is moved in the other direction such that it is now the second block channel 42 which communicates with the pilot channel 52. Because it is low pressure fluid, neither of the valve bodies 66 of selection valves 60 and 61 move from the position shown in Figure 2B . However, the hydraulic fluid flows through second selection valve 61 in the same manner as described for the first selection valve 60.
- the hydraulic fluid flows out of third operator port 48 and into line 86 to the fork positioner 80. This causes the fork positioner to operate in the opposite direction.
- Hydraulic fluid flowing out of fork positioner 80 into line 84 enters the valve assembly 10 at first operator port 44.
- the returning fluid is directed into first channel 40 by the first selection valve 60, as described above.
- the fluid exits at first supply port 32 and is returned to the tank return line 20 via first supply line 12.
- moving the lever 28 either way causes the fork positioner 80 to move in either direction (i.e. narrowing or widening the fork spacing).
- high pressure means pressure of 2.17 MPa (315 PSI) or higher.
- the hydraulic fluid enters the first chamber 36 along the same path as described for the narrowing function of the fork positioner.
- the now high pressure fluid passes to the pilot channel 52 and acts against surface 68 of each of the valve bodies 66 of the selection valves 60 and 61. Because the pressure in the pilot channel 52 acting against pressure surface 68 of each valve body 66 is greater than the resistance of the respective springs 74, the valve body 66 of each selection valve moves against the spring 74. This moves the valve bodies 66 to the positions shown in Figures 5C and 5D , and thereby permits fluid in first block channel 40 to flow through annular space 69 and into second operator port 46. O-ring 72 prevents fluid communication with first operator port 44.
- hydraulic fluid flows to the side shifter 82 along line 88.
- Hydraulic fluid returns to fourth operator port 50 along line 90, then through selection valve 61.
- the fluid flows through the valve block 30 and out through the second supply port 34 in a manner analogous to the manner described above.
- the fluid is returned to the tank in the same manner as described for the narrowing function of the fork positioner.
- the hydraulic operators are able to achieve their required functions while operating at different pressures.
- One pressure is referred to herein as the lower pressure, while the other pressure is referred to as the higher pressure.
- Absolute values are, of course, widely variable. However, it is preferred that the two pressures differ by about 0.345 MPa (50 PSI).
- fork positioning can be successfully preformed using pressures of less than 1.72 MPa (250 PSI), while side shifting can be accomplished using pressures above 2.24 MPa (325 PSI).
- Other pressures and other pressure differentials can be used depending on the vehicle and the implements being controlled.
- the high pressure in the supply lines 12 and 14 is achieved by moving lever 28 quickly to the full open position in the desired direction.
- the lever When fork positioning is desired, the lever is moved in the desired direction only part way.
- the initial fluid pressure available at control panel 11 is usually relatively low and, in any event, only a restricted flow occurs.
- the restricted flow occurs at a lower pressure, and thus, fluid reaching the valve assembly 10 is at the lower pressure.
- the forks can be moved using the lower pressure.
- the restricted fluid continues to flow as the forks move and pressure does not build up in supply lines 12 or 14 or in valve block 30.
- This means the selection valves 60 and 61, remain in the starting position shown in Figures 2A and 2B under the pressure exerted by spring 74 and fork positioning continues to occur for as long as desired and in the direction desired
- the orifice valve 35 may be provided to reduce any hammer effect which may be caused by sudden changes in direction of the fluid flow.
- the preferred embodiment of the invention described above is configured to provide selectable, two-way, hydraulically actuated movement.
- certain hydraulic operators may require only one way movement.
- the return movement of the hydraulic operator may be provided by some other source, such as a spring or gravity.
- the second supply port 34, second block channel 42, second selection valve 61, bi-directional valve 56, and third and fourth operator ports 48, 50 may be omitted.
Abstract
Description
- The invention is related to hydraulic systems, and in particular, to a multi-function hydraulic valve assembly.
- The use of hydraulic systems for moving or lifting loads is well known. Typically, such systems utilize hydraulic fluid under pressure to drive hydraulic operators, such as piston/cylinder arrangements. A piece of machinery, such as a hoist or a truck, may require several hydraulic operators to move the load in different ways. Typically, the various hydraulic operators are each controlled by a lever located in the cab of the machine or vehicle. One example where hydraulic systems are used in this way are lift trucks.
- Lift trucks are vehicles which are used to pick up and move loads from place to place. A conventional lift truck includes a carriage which supports a pair of forks. The forks are maneuvered into place by the lift truck operator and are used to pick up the load. The carriage rides vertically in a mast, which also supports the carriage. In addition the mast may be tilted backward to facilitate stabilizing the load on the forks. Two separate hydraulic operators are used to move the carriage vertically and to tilt the mast.
- Several attachments to enhance the capabilities of the lift truck are known in the art. One such attachment is a side shift assembly which facilitates aligning the spaced pair of forks with the load. The term "side shifting" is used io describe the concept of shifting the forks as a spaced pair either left or right of the vehicle center line. This function provides the operator with a greater margin for error when aligning the vehicle with the load. A hydraulic operator, such as a piston/cylinder arrangement is typically used by the side shifting assembly to move a frame to which the forks are secured.
- Another attachment to enhance the capability of a lift truck is a fork positioning assembly. The term fork positioning is used to describe the concept of changing the relative spacing between the forks to accommodate loads of different widths. Again, a hydraulic operator, such as a piston/cylinder arrangement is used in the fork positioning assembly to move the forks.
- A cab of a conventional lift truck provides three levers to operate three hydraulic operators. Accordingly, if a user requires four hydraulic operators, such as, for example, by installing a fork positioning attachment, an additional lever must be installed to operate the fork positioning attachment.
- Alternatively, prior art systems such as
US-A-5 139 385 permit operation of two separate hydraulic operators with a single lever on a lift truck. These systems utilize an electrical circuit to toggle between the two hydraulic operators. Prior to moving the lever which actuates the hydraulic system, the user would activate the electrical switch to select the appropriate hydraulic operator. This system adds expense and complexity to the design of the lift truck. In addition, electrical cables must be provided and extended over the lift truck mast. - Accordingly, there is a need for a hydraulic valve assembly which permits selectable hydraulic operation of more than one hydraulic operator with a single lever.
-
FR2720123 - The present invention relates to a hydraulic valve assembly as set out in
claim 1. - The invention will now be described, by way of example only, with reference to the accompanying figures, where:
-
Figure 1 is a schematic of a hydraulic system for a lift truck; -
Figure 2 is a perspective view of a valve assembly according to a preferred embodiment of the present invention; -
Figure 3 is a cross-sectional view of a valve block for the preferred embodiment ofFigure 2 ; -
Figure 4 is a perspective view of a selection valve for the preferred embodiment ofFigure 2 ; -
Figure 5A is a cross-sectional view of the preferred embodiment ofFigure 2 in a first position showing fluid flow in one direction; -
Figure 5B is a cross-sectional view of the preferred embodiment in the first position as shown inFigure 5A , but showing fluid flow in an opposite direction; -
Figure 5C is a cross-sectional view of the preferred embodiment ofFigure 2 in a second position showing fluid flow in one direction; -
Figure 5D is a cross-sectional view of the preferred embodiment in the second position, as shown inFigure 5C , but showing fluid flow in the opposite direction; and -
Figure 6 is a schematic view showing the preferred embodiment ofFigure 2 connected to a side shifter and fork positioner. -
Figure 1 shows a hydraulic system for a lift truck connected to avalve assembly 10 according to a preferred embodiment of the present invention. Thevalve assembly 10 is connected to acontrol panel 11 by a firsthydraulic supply line 12 and a secondhydraulic supply line 14. Thecontrol panel 11 is connected to ahydraulic fluid tank 16 by atank supply line 18 and atank return line 20. A pump (not shown) is connected to thetank supply line 18 to provide the hydraulic fluid under pressure. - Referring again to
Figure 1 , thecontrol panel 11 includes ahydraulic circuit 26 to interchangeably connect the tank supply andreturn lines hydraulic supply lines circuit 26 is operated in a conventional manner and will not be further described. - the
circuit 26 is hydraulically connected to three corresponding levers in the lift truck cab. Other similar circuits may be used to control other vehicle functions such as mast tilting, carriage raising, and the like. For convenience, only thelever 28 for operating theparticular circuit 26 is shown. It will be understood by those skilled in the art that other types of actuators may be provided. - Referring now to
Figure 2 , the valve assembly includes avalve block 30, which preferably has a box-like shape. Afirst supply port 32 and asecond supply port 34 are provided in thevalve block 30. The first andsecond supply ports hydraulic supply lines 12, 14 (shown inFigure 1 ), respectively. Preferably thesupply ports block 30. An orifice valve 35(shown inFigures 5A-5D ) is preferably provided between thesupply ports - Referring now to
Figure 3 , afirst chamber 36 and asecond chamber 38 are provided in thevalve block 30. The first andsecond chambers second supply ports second block channels - Referring again to
Figure 3 , four operator ports are provided in thevalve block 30. Preferably, afirst operator port 44 and asecond operator port 46 are provided on one face of theblock 30, and athird operator port 48 and afourth operator port 50 are provided on the opposite face of theblock 30. The first andsecond operator ports first chamber 36. The third andfourth operator ports second chamber 38. - Referring now to
Figure 6 , The first andthird operator ports hydraulic operator 80. The first hydraulic operator may be, for example, a fork positioning cylinder. The second andfourth operator ports hydraulic operator 82. The second hydraulic operator may be, for example, a side shifting cylinder. - Referring again to
Figure 3 , apilot channel 52 is provided in thevalve block 30. Thepilot channel 52 communicates with first andsecond chambers pilot channel 52 also communicates with first andsecond block channels intersection 54. As shown schematically inFigures 5A-5D , abi-directional valve 56 is located in theintersection 54. Preferably, the bi-directional valve is a conventional ball and shuttle valve. The bi-directional valve alternatively connectspilot channel 52 withblock channel 40 orblock channel 42. - Referring now to
Figures 4 and5A-D , a firstconventional selection valve 60 is located in thefirst chamber 36 and a secondconventional selection valve 61 is located in thesecond chamber 38. Preferably, theselection valves first selection valve 60 includes a generallycylindrical valve housing 62 mounted in thefirst chamber 36. Thecylindrical valve housing 62 has an open end proximate to thepilot channel 52, and defines aninternal valve chamber 64. Thecylindrical valve housing 62 also includes a plurality of radially directed circumferentially arrangedopenings 65 for communicating with thefirst chamber 36. A movingvalve body 66 is located within thevalve chamber 64 ofvalve housing 62. Thevalve body 66 has apressure surface 68 adjacent the open end of thevalve housing 62. Thevalve body 66 has a narrower portion which defines anannular space 69. The radially directedopenings 65 communicate with theannular space 69 between thevalve body 66 and thevalve housing 62. Thevalve body 66 is connected to aspring 74 located in a closed end of thecylindrical valve housing 62.Valve body 66 may be moved relative tovalve housing 62 by collapsing thespring 74. Thespring 74 biases thevalve body 66 to the position shown inFigures 5A and5B . Preferably, the spring resistance is configured such that a pressure of 2.17 MPa (315 PSI) or greater applied to pressuresurface 68 is required to collapse thespring 74 so that thevalve body 66 may move to the position shown inFigures 5C and5D . - A number of external O-
rings first selection valve 60 against portions of the wall of thefirst chamber 36. Internal O-rings (not shown) are also provided to seal the upper and lower ends of theannular space 69 from the remainder of thevalve chamber 64 to prevent bleeding of fluid between thevalve body 66 andvalve housing 62. - As the
second selection valve 61 is the same as thefirst selection valve 60, it will not be described in detail. - Referring now to
Figure 6 , the operation of thevalve assembly 10 according to the present invention will now be described. For convenience, the operation of the present invention will be described in conjunction with a conventional hydraulically-operatedfork positioner 80 andside shifter 82 for a lift truck. For the purposes of the description, the first hydraulic operator will be the fork positioner, and the second hydraulic operator will be the side shifter. It will be understood by those skilled in the art that the present invention may be operated with any two hydraulic operators requiring different pressure, and is not confined to fork positioners and side shifters, or to hydraulic operators for lift trucks. The operators could be used for any desired function, such as rotating, tilting, clamping, or the like. - Referring to
Figure 1 , when the lift truck operator wishes to actuate the fork positioner in a first direction, such as to narrow the forks, the operator moves thelever 28 part-way in one direction. Thecircuit 26 is partially activated to supply hydraulic fluid from thehydraulic fluid tank 16 alongtank supply line 18, throughsection 22, and then to the firsthydraulic supply line 12. Because, thecircuit 26 is only, parity activated, the flow rate of hydraulic fluid in the firsthydraulic supply line 12 is low, resulting in low pressure as explained below. Preferably, low pressure means pressure below 2.17 MPa (315 PSI). - Referring now to
Figure 5A the hydraulic fluid enters thefirst supply port 32 and flows intofirst channel 40. The pressure of the fluid infirst block channel 40 moves thebi-directional valve 56 into a position permitting fluid communication betweenfirst block channel 40 andpilot channel 52, while sealing off communication betweensecond block channel 42 and thepilot channel 52. The pressure of the fluid in thepilot channel 52 acts on thepressure surface 68 of each of theselection valves valve bodies 66 of theselection valves selection valves first operator port 44 andthird operator port 48, respectively. The supply fluid infirst block channel 40 also enters theannular space 69 through the radially directedopenings 65 in thecylindrical housing 62 of thefirst selection valve 60. The fluid exits from theannular space 69 offirst selection valve 60 through additional radially directedopenings 65 and entersfirst operator port 44. The fluid is prevented from enteringsecond operator port 46 by O-ring 70 and the internal O-rings of theselection valve 60. - Referring to
Figure 6 , the hydraulic fluid travels to thefork positioner 80 byline 84 connected tofirst operator port 44. As the fork positioner is actuated to narrow the forks, hydraulic fluid also leaves thefork positioner 80 and entersthird operator port 48 vialine 86. The fluid is routed tosecond block channel 42 through thesecond selection valve 61, in a similar but reverse manner as described forfirst selection valve 60. The fluid exits thevalve assembly 10 atsecond supply port 34 alongsecond supply line 14. - Referring now to
Figure 1 , the fluid travels along secondhydraulic supply line 14 tocircuit 26 and is directed intotank return line 20 to complete the loop. - If the operator wishes to widen the forks, the operator moves the
lever 28 part-way in the opposite direction causing thecircuit 26 to partially activate so thatsection 24 is employed to direct a low pressure flow of fluid from the hydraulicfluid supply tank 16 into the secondhydraulic supply line 14. - Referring now to
Figure 5B , the hydraulic fluid enters thevalve block 30 via thesecond supply port 34 and into thesecond block channel 42. Thebi-directional valve 56 is moved in the other direction such that it is now thesecond block channel 42 which communicates with thepilot channel 52. Because it is low pressure fluid, neither of thevalve bodies 66 ofselection valves Figure 2B . However, the hydraulic fluid flows throughsecond selection valve 61 in the same manner as described for thefirst selection valve 60. The hydraulic fluid flows out ofthird operator port 48 and intoline 86 to thefork positioner 80. This causes the fork positioner to operate in the opposite direction. - Hydraulic fluid flowing out of
fork positioner 80 intoline 84, enters thevalve assembly 10 atfirst operator port 44. The returning fluid is directed intofirst channel 40 by thefirst selection valve 60, as described above. The fluid exits atfirst supply port 32 and is returned to thetank return line 20 viafirst supply line 12. Thus, moving thelever 28 either way causes thefork positioner 80 to move in either direction (i.e. narrowing or widening the fork spacing). - Referring to
Figure 1 , if the lift truck operator wishes to actuate the side shifter in one direction, the operator moves thelever 28 all the way in the first direction. Thecircuit 26 is fully activated, routing the fluid fromtank supply line 18 throughsection 22 tofirst supply line 12. Full activation ofcircuit 26 results in high pressure infirst supply line 12. Preferably, high pressure means pressure of 2.17 MPa (315 PSI) or higher. - Referring to
Figure 5C , the hydraulic fluid enters thefirst chamber 36 along the same path as described for the narrowing function of the fork positioner. In addition, the now high pressure fluid passes to thepilot channel 52 and acts againstsurface 68 of each of thevalve bodies 66 of theselection valves pilot channel 52 acting againstpressure surface 68 of eachvalve body 66 is greater than the resistance of therespective springs 74, thevalve body 66 of each selection valve moves against thespring 74. This moves thevalve bodies 66 to the positions shown inFigures 5C and5D , and thereby permits fluid infirst block channel 40 to flow throughannular space 69 and intosecond operator port 46. O-ring 72 prevents fluid communication withfirst operator port 44. Accordingly, hydraulic fluid flows to theside shifter 82 alongline 88. Hydraulic fluid returns tofourth operator port 50 alongline 90, then throughselection valve 61. The fluid flows through thevalve block 30 and out through thesecond supply port 34 in a manner analogous to the manner described above. The fluid is returned to the tank in the same manner as described for the narrowing function of the fork positioner. - If the lift truck operator wishes to actuate the side shifter in the opposite direction, the operator moves the
lever 28 all the way in the opposite direction, thus employingcomponent 24, and thereby initiating high pressure flow as described above. As shown inFigure 5D , the path of the high pressure hydraulic fluid flow through the system is reversed, as described for the widening function of the fork positioner. The valve assembly operation is as described above. - Preferably, the hydraulic operators are able to achieve their required functions while operating at different pressures. One pressure is referred to herein as the lower pressure, while the other pressure is referred to as the higher pressure. Absolute values are, of course, widely variable. However, it is preferred that the two pressures differ by about 0.345 MPa (50 PSI). For example, in one lift truck, fork positioning can be successfully preformed using pressures of less than 1.72 MPa (250 PSI), while side shifting can be accomplished using pressures above 2.24 MPa (325 PSI).
Other pressures and other pressure differentials can be used depending on the vehicle and the implements being controlled. The high pressure in thesupply lines lever 28 quickly to the full open position in the desired direction. When the lever is moved, maximum flow rate through thecontrol panel 11 occurs and pressure quickly builds in thesupply line valve block 30, which shiftsselection valves control panel 11 and fluid pressure will very quickly build up to cause movement of theselection valves - When fork positioning is desired, the lever is moved in the desired direction only part way. The initial fluid pressure available at
control panel 11 is usually relatively low and, in any event, only a restricted flow occurs. The restricted flow occurs at a lower pressure, and thus, fluid reaching thevalve assembly 10 is at the lower pressure. Because fork positioning occurs when the forks are not loaded, the forks can be moved using the lower pressure. Thus, the restricted fluid continues to flow as the forks move and pressure does not build up insupply lines valve block 30. This, in turn, means theselection valves Figures 2A and 2B under the pressure exerted byspring 74 and fork positioning continues to occur for as long as desired and in the direction desired - The
orifice valve 35 may be provided to reduce any hammer effect which may be caused by sudden changes in direction of the fluid flow. - The preferred embodiment of the invention described above is configured to provide selectable, two-way, hydraulically actuated movement. However, certain hydraulic operators may require only one way movement. The return movement of the hydraulic operator may be provided by some other source, such as a spring or gravity. For such hydraulic operators, the
second supply port 34,second block channel 42,second selection valve 61,bi-directional valve 56, and third andfourth operator ports - The present invention may be embodied in other specific forms without departing from the essential characteristics thereof. The presently disclosed embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Claims (18)
- A hydraulic valve assembly (10) for selectably delivering hydraulic fluid from a supply (16) of hydraulic fluid to one of a first hydraulic operator (80) and a second hydraulic operator (82), said assembly comprising:a) a valve block (30) defining:i) a first supply port port (32) adapted for fluid communication with said supply (16);ii) a second supply port (34) adapted for fluid communication with said supply (16);iii) a first operator port (44) adapted for fluid communication with said first hydraulic operator (80);iv) a second operator port (46) port adapted for fluid communication with said second hydraulic operator (82);v) a third operator port (48) adapted for fluid communication with said first hydraulic operator (80);vi) a fourth operator port (50) adapted for fluid communication with said second hydraulic operator (82);vii)a first chamber (36), said first chamber being in fluid communication with said first supply port (32) said first operator port (44) and said second operator port (46);viii) a second chamber (38), said second chamber being in fluid communication with said second supply port (34) said third operator port (48) and said fourth operators port (50);b) a first selection valve (60) located in said first chamber (36) and a second selection valve (61) located in said second chamber (38), said first and second selection valves (60, 61) being adapted to move in unison, said first and second selection valves (60, 61) operable between a first position when said hydraulic fluid is at a first pressure and a second position when said hydraulic fluid is at a second pressure, where in said first position, said first selection valve (60) permits fluid communication between said first supply port (32) and said first operator port (44), and said second selection valve (61) permits fluid communication between said second supply port (34) and said third operator port (48), where, in said second position, said first selection valve (60) permits fluid communication between said first supply port (32) and said second operator port (46), and said second selection valve (61) permits fluid communication between said second supply port (34) and said fourth operator port (50);wherein said first pressure is lower than said second pressure.
- The assembly (10) of claim 1, further comprising an actuator (28) operatively connected to said supply (16), said actuator (28) being selectably movable among a first actuator position adapted to deliver said hydraulic fluid to said first supply port (32) at said first pressure, a second actuator position adapted to deliver said hydraulic fluid to said first supply port (32) at said second pressure, a third actuator position adapted to deliver said hydraulic fluid to said second supply port (34) at said first pressure, and a fourth actuator position adapted to deliver said hydraulic fluid to said second supply port (34) at said second pressure, said first and third actuator positions being adapted to permit reciprocal movement of said first hydraulic operator (80) and said second and fourth actuator positions permitting reciprocal movement of said second hydraulic operator (82).
- The assembly (10) of claim 2, wherein when said actuator (28) is in said first and second positions, said hydraulic fluid is returned to said supply (16) from said second supply port (34), and when said actuator (28) is in said third and fourth positions, said hydraulic fluid is returned to said supply (16) from said first supply port (32).
- The assembly (10) of claim 3 wherein said actuator (28) comprises a lever connected to a hydraulic circuit (26).
- The assembly (10) of claim 4, wherein said lever (28) is movable from a central at rest position in two opposing directions, where in said first actuator position, said lever (28) is at part travel in one direction and in said third actuator position, said lever (28) is at part travel in an opposite direction, where in said second actuator position, said lever (28) is at substantially full travel in said one direction and in said fourth actuator position, said lever (28) is at substantially full travel in said opposite direction.
- The assembly (10) of claim 1, wherein said valve block (30) defines a pilot channel (52), said pilot channel (52) being adapted for fluid communication with said first chamber (36) said second chamber (38), and one of said first supply port (32) and said second supply port (34), said first and second selection valves (60, 61) being adapted for movement by pressure in said pilot channel (52).
- The assembly (10) of claim 6 wherein said valve block (30) defines a first and a second block channel (40, 42), said first block channel (40) extending between said first supply port (32) and said first chamber (36), said second block channel (42) extending between said second supply port (34) and said second chamber (38).
- The assembly (10) of claim 7, further comprising a bi-directional valve (54) located at an intersection of said pilot channel (52), said first block channel (40) and said second block channel (42), said bi-directional valve (54) being adapted to provide fluid communication between said first block channel (40) and said pilot channel (52) when said hydraulic fluid is flowing into said first supply port (32), and between said second block channel (42) and said pilot channel (52) when said hydraulic fluid is flowing into said second supply port (34).
- The assembly (10) of claim 8, wherein said bi-directional valve (54) comprises a ball and shuttle valve.
- The assembly (10) of claim 8, wherein said first selection valve (60) comprises:a) a valve housing (62) defining an open end proximate to said pilot channel (52) and an opposing closed end, said valve housing defining an internal valve chamber (64) communicating with said open end;b) a valve body (66) movably received within said internal valve chamber (64), said valve body (66) defining a pressure surface (68) proximate to said open end of said internal valve chamber (64), wherein said valve body (66) is moved from said first position to said second position by pressure in said pilot channel (52) acting on said pressure surface (68); andc) a biasing means (74) for urging said valve body toward (66) said first position.
- The assembly (10) of claim 10, wherein said biasing means (74) is located in said closed end of said valve housing (62).
- The assembly (10) of claim 11, wherein said biasing means (74) comprises a spring.
- The assembly (10) of claim 12, wherein a pressure of 2.17 MPa (315 PSI) or greater acting against said pressure surface (68) is required to overcome the resistance of said spring (74).
- The assembly (10) of claim 13, wherein said valve housing (62) defines a plurality of circumferentially arranged openings (65).
- The assembly (10) of claim 14, wherein said second selection valve (61) is substantially identical to said first selection valve (60).
- The assembly (10) of claim 8, wherein said first hydraulic operator (80) is a fork positioner for a lift truck, and said second hydraulic operator (82) is a side shifter for a lift truck.
- The assembly (10) of claim 12, wherein said valve block (30) has a box shape, said valve block defining a first face, a second face, and a third face.
- The assembly (10) of claim 17, wherein said first and second supply ports (32, 34) are located on said first face, said first and second operator ports (44, 46) are located on said second face, and said third and fourth operator ports (48, 50) are located on said third face.
Applications Claiming Priority (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US36107502P | 2002-03-01 | 2002-03-01 | |
US361075P | 2002-03-01 | ||
US120789 | 2002-04-12 | ||
US10/120,789 US6782910B2 (en) | 2002-03-01 | 2002-04-12 | Multi-function hydraulic valve assembly |
PCT/CA2003/000212 WO2003074884A1 (en) | 2002-03-01 | 2003-02-14 | Multi-function hydraulic valve assembly |
Publications (2)
Publication Number | Publication Date |
---|---|
EP1481168A1 EP1481168A1 (en) | 2004-12-01 |
EP1481168B1 true EP1481168B1 (en) | 2009-09-30 |
Family
ID=27807301
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP20030701411 Expired - Lifetime EP1481168B1 (en) | 2002-03-01 | 2003-02-14 | Multi-function hydraulic valve assembly |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP1481168B1 (en) |
JP (1) | JP2005519244A (en) |
CN (1) | CN100404882C (en) |
AT (1) | ATE444449T1 (en) |
AU (1) | AU2003203106A1 (en) |
CA (1) | CA2476759C (en) |
DE (1) | DE60329471D1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102014101764A1 (en) * | 2014-02-12 | 2015-08-13 | Jungheinrich Aktiengesellschaft | Control block for a hydraulic system of a truck with at least one hydraulic valve |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104803290B (en) * | 2015-04-21 | 2017-04-12 | 青岛港国际股份有限公司 | Lifting mechanism of quay cranes and method for lifting quay crane components by adopting lifting mechanism |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL7203122A (en) * | 1972-03-09 | 1973-09-11 | ||
US3782249A (en) * | 1972-11-16 | 1974-01-01 | Allis Chalmers | Hydraulic control system with locking valve to prevent accidental or unauthorized lowering of a tractor implement |
CN1017276B (en) * | 1988-02-17 | 1992-07-01 | 通用电气公司 | Fluidic multiplexer |
CN1021648C (en) * | 1989-10-04 | 1993-07-21 | 日本石油化学株式会社 | Cargo work control apparatus for forklift truck |
US5139385A (en) * | 1990-04-03 | 1992-08-18 | Swingshift Manufacturing, Inc. | Dual pallet fork attachment for a lift truck |
FR2720123B1 (en) * | 1994-05-19 | 1996-08-14 | France Power Packer Sa | Hydraulic control automation, especially for plows. |
-
2003
- 2003-02-14 DE DE60329471T patent/DE60329471D1/en not_active Expired - Lifetime
- 2003-02-14 EP EP20030701411 patent/EP1481168B1/en not_active Expired - Lifetime
- 2003-02-14 CN CNB038049597A patent/CN100404882C/en not_active Expired - Lifetime
- 2003-02-14 AT AT03701411T patent/ATE444449T1/en not_active IP Right Cessation
- 2003-02-14 AU AU2003203106A patent/AU2003203106A1/en not_active Abandoned
- 2003-02-14 JP JP2003573302A patent/JP2005519244A/en active Pending
- 2003-02-14 CA CA 2476759 patent/CA2476759C/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102014101764A1 (en) * | 2014-02-12 | 2015-08-13 | Jungheinrich Aktiengesellschaft | Control block for a hydraulic system of a truck with at least one hydraulic valve |
Also Published As
Publication number | Publication date |
---|---|
CN1639467A (en) | 2005-07-13 |
CA2476759C (en) | 2011-07-26 |
CA2476759A1 (en) | 2003-09-12 |
CN100404882C (en) | 2008-07-23 |
AU2003203106A1 (en) | 2003-09-16 |
ATE444449T1 (en) | 2009-10-15 |
EP1481168A1 (en) | 2004-12-01 |
DE60329471D1 (en) | 2009-11-12 |
JP2005519244A (en) | 2005-06-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4072087A (en) | Digital positioner for remote actuation of a control valve | |
EP0391307B1 (en) | Hydraulic control circuit arrangement for a single-acting cylinder | |
JP2007239992A (en) | Hydraulic system including plurality of pressure relief level | |
US6212886B1 (en) | Hydraulic drive system and directional control valve apparatus in hydraulic machine | |
EP1434943B1 (en) | Multiple hydraulic valve assembly with a monolithic block | |
US5845678A (en) | Pressurized fluid supply system | |
JP3119722B2 (en) | Hydraulic circuit of 4-position closed center switching valve by pressure proportional control valve | |
GB2081394A (en) | Hydraulic systems | |
KR910007287B1 (en) | Direction control valve fitted with flow control mechanism | |
US5115720A (en) | Hydraulic valve bank | |
US6161467A (en) | Fluid control system with regeneration | |
JPS6361524B2 (en) | ||
US6782910B2 (en) | Multi-function hydraulic valve assembly | |
US11466706B2 (en) | Valve device | |
US3996840A (en) | Control circuit of actuator | |
US6173639B1 (en) | Fluid control system having float control | |
CN113544390A (en) | Flow control valve | |
US5832808A (en) | Directional control valve unit | |
US5081905A (en) | Hydraulic pilot operation circuit and valve for quickly discharging oil | |
US6186044B1 (en) | Fluid control system with float capability | |
US5209263A (en) | Pilot valve assembly | |
EP1481168B1 (en) | Multi-function hydraulic valve assembly | |
US4099541A (en) | Power transmission | |
US4215622A (en) | Hydraulic control system | |
EP1961973B1 (en) | Actuator control device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
17P | Request for examination filed |
Effective date: 20040920 |
|
AK | Designated contracting states |
Kind code of ref document: A1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT SE SI SK TR |
|
AX | Request for extension of the european patent |
Extension state: AL LT LV MK RO |
|
R17P | Request for examination filed (corrected) |
Effective date: 20040920 |
|
17Q | First examination report despatched |
Effective date: 20070809 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT SE SI SK TR |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D Ref country code: CH Ref legal event code: EP |
|
REG | Reference to a national code |
Ref country code: IE Ref legal event code: FG4D |
|
REF | Corresponds to: |
Ref document number: 60329471 Country of ref document: DE Date of ref document: 20091112 Kind code of ref document: P |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: SE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SI Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 |
|
NLV1 | Nl: lapsed or annulled due to failure to fulfill the requirements of art. 29p and 29m of the patents act | ||
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: PT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20100201 Ref country code: CZ Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: EE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: ES Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20100110 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: CY Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: AT Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: BE Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: DK Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20100701 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20091231 Ref country code: CH Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100228 Ref country code: LI Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100228 Ref country code: MC Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100301 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100214 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100214 |
|
PGRI | Patent reinstated in contracting state [announced from national office to epo] |
Ref country code: IT Effective date: 20110616 |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: 732E Free format text: REGISTERED BETWEEN 20111201 AND 20111207 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R082 Ref document number: 60329471 Country of ref document: DE Representative=s name: LEINWEBER & ZIMMERMANN, DE |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R081 Ref document number: 60329471 Country of ref document: DE Owner name: LIFT TECHNOLOGIES, INC., WESTMINSTER, US Free format text: FORMER OWNER: LIFT TECHNOLOGIES INC., GUELPH, ONTARIO, CA Effective date: 20120203 Ref country code: DE Ref legal event code: R082 Ref document number: 60329471 Country of ref document: DE Representative=s name: LEINWEBER & ZIMMERMANN, DE Effective date: 20120203 Ref country code: DE Ref legal event code: R081 Ref document number: 60329471 Country of ref document: DE Owner name: LIFT TECHNOLOGIES, INC., US Free format text: FORMER OWNER: LIFT TECHNOLOGIES INC., GUELPH, CA Effective date: 20120203 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: BG Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 Ref country code: HU Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20100401 Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20100214 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: TR Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT Effective date: 20090930 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 14 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 15 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 16 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20220210 Year of fee payment: 20 Ref country code: DE Payment date: 20220214 Year of fee payment: 20 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20220208 Year of fee payment: 20 Ref country code: FR Payment date: 20220208 Year of fee payment: 20 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R071 Ref document number: 60329471 Country of ref document: DE |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: PE20 Expiry date: 20230213 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION Effective date: 20230213 |