WO2008002505A2

WO2008002505A2 - Deactivating hydraulic piston pump-high pressure

Info

Publication number: WO2008002505A2
Application number: PCT/US2007/014659
Authority: WO
Inventors: David B. Roth
Original assignee: Borgwarner Inc.
Priority date: 2006-06-27
Filing date: 2007-06-25
Publication date: 2008-01-03
Also published as: WO2008002505A8; WO2008002505A3

Abstract

The present invention is a hydraulic pump having a body having one or more cylinders, and at least one collapsible link, selectively actuatable into a first position and a second position. The at least one collapsible iink is located in the one or more cylinders. The pump also has at least one cam operably associated with the body,. and with the collapsible link. As the cam rotates, the cam will cause the collapsible link to slidably move within the cylinders when the collapsible link is in the first position, and when the collapsible link is in the second position,; a portion of the collapsible link is collapsed by engagement with the cam.

Description

DEACTIVATING HYDRAULIC PISTON PUMP - HIGH PRESSURE

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 60/816,662, filed June 27, 2006.

FIELD OF THE INVENTION

The present invention relates to hydraulic pumps which can be deactivated when pumping action is not necessary. Particularly, the present invention relates to a hydraulic pump, driven by a rotational crankshaft such as in an engine, where the pump can be deactivated. More particularly, the present invention is a hydraulic oil pump which has a collapsible solid link between a rotational camshaft or other hydraulic system, where the collapsible solid link can be deactivated when the pumping action is not necessary.

BACKGROUND OF THE INVENTION

Certain engine systems require oil delivery at a higher pressure than what is available from the engine lubrication system. Currently, there are variable valve timing systems that utilize an extra external high pressure oil pump running at two to three times the lubrication system pressure. Other foreseeable systems may require 1000 to 3000 psi. For most of these applications, the need for hydraulic supply is very intermittent.

SUMMARY OF THE INVENTION

The present invention is a pump for intermittently supplying high oil pressure to a variety of hydraulic systems such as an auxiliary engine system, that includes the need to refill an oil pressure accumulator, operate a high pressure fuel pump, or supply hydraulic fluid at high pressure. In the present invention, a hydraulic pump having a body having one or more cylinders, and at least one collapsible link, selectively actuatable to be in either a first position or a second position is provided. The collapsible link is located in the one or more cylinders. The pump also has at least one cam operably associated with the body, and with the collapsible link. As the cam rotates, the collapsible link slidably moves within the cylinders, when the collapsible link is in the first position, and when the collapsible link is in the second position, a portion of the collapsible link is collapsed by engagement with the cam.

Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:

Figure 1 is a wire diagram of a top view of a hydraulic pump, according to the present invention;

Figure 2 is a wire diagram of a side view of a hydraulic pump, according to the present invention; Figure 3 is a sectional side view taken along line 3-3 of Figure 1 , according to the present invention;

Figure 4 is a sectional front view taken along 4-4 of Figure 1, according to the present invention;

Figure 5 is a sectional rear view taken along 5-5 of Figure 1, according to the present invention;

Figure 6 is a sectional rear view taken along 6-6 of Figure 1, according to the present invention;

Figure 7 is an enlarged view of a collapsible link in a collapsible telescoped configuration, according to the present invention; Figure 8 is a sectional bottom view taken along 7-7 of Figure 2, according to the present invention;

Figure 9 is a perspective view of a hydraulic pump according to an alternate embodiment of the present invention; Figure 10 is a perspective view of a hydraulic pump with the body removed, according to an alternate embodiment of the present invention;

Figure 11 is a perspective view of an alternate embodiment of a hydraulic pump showing apertures in phantom, according to an alternate embodiment of the present invention; and

Figure 12 is a perspective view of a hydraulic pump with the housing removed, according to an alternate embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.

Referring to Figures 1-8, a hydraulic pump according to the present invention is generally shown at 10. The pump 10 has a housing 12, which is includes of a top plate 14, a body 16 having a series of one or more cylinders 18 and two semi-circular recesses 20. In the embodiment shown, four cylinders 18 are used, but it is within the scope of the invention that more or less cylinders 18 can be used to suit a particular application. The housing also has a bottom portion 22 which includes a block portion 24 having two semi-circular recesses 26, the block portion 24 being connected to a U- shaped flange 28. The top plate 14, body 16, and bottom portion 22 are connected by a series of bolts 30 which extend through holes 31 in the top plate 14, body 16, and bottom portion 22. The top plate 14 also includes two openings 34 which are located above each of the cylinders 18. The openings 34 are used for receiving check valves 36 which are used to pump fluid into and out of the cylinder 18.

The semi-circular recesses 20 on the body 16 and the semi-circular recesses 26 on the block portion 24 form circular apertures 32. The circular apertures 32 receive and support a camshaft 38 having a series of one or more cams 40. The camshaft 38 also has a pulley 42 located on one end. The pulley 42 can be connected to a belt or chain (not shown), which is then connected to the crankshaft of an engine; the rotation of the crankshaft of the engine provides power to the pump 10. The cylinders 18 in the body 16 receive a series of one or more collapsible links 44. Each collapsible link 44 includes an inner member, which in this embodiment is an inner cylinder 46 having a circular cross-section received by an outer member, which in this embodiment is an outer cylinder 48 having a circular cross-section. Each inner cylinder 46 has an aperture 50 which receives a locking member, in this case a pin generally shown at 52, and a recess 54. The pin 52 is located in the aperture 50, and has a base portion 56 fixedly mounted inside the aperture 50, and a moveable portion 58 that slides in the aperture 50, the moveable portion 58 is attached to the base portion 56 through the use of a spring 60. The cross-section of the inner member and outer member of each cylinder 18 does not have to be circular, the cross-section of the inner member and outer member could also be in the shape of a square, or any other shape necessary for the particular application the present invention is being used for. Also, the locking member does not necessarily have to be a pin 52, the locking member could also be a disc, tube, or other movable piece which could connect the inner member and outer member. More detail of the function of the recess 54 will be described later.

Each outer cylinder 48 is hollow and receives the inner cylinder 46 and a spring 62. Each outer cylinder 48 has a flat bottom surface 64 which is used to compress the spring 62, and a roller 66 which is connected to the outer cylinder 48 through the use of a roller pin 68. The spring 62 is positioned between the bottom surface 64 and the inner cylinder 46. The roller 66 of each outer cylinder 48 is in rolling contact with a respective cam 40 on the camshaft 38. Each outer cylinder 48 also has a port 70 in line with the aperture 50 located in the inner cylinder 46. Also disposed within the cylinder 36 is a return spring 72, which contacts the bottom surface of the top plate 14, and the outer diameter of the inner cylinder 46. The function of the return spring 72 is to ensure that the roller 66 remains in contact with the cam 40 at all times during operation. Referring specifically to Figure 8, there are four fluid conduits 74 which are used to actuate the pin 52 in each collapsible link 40. Located in each fluid conduit 74 is a circular orifice 76. There is a first spool valve 78 for directing fluid to two of the collapsible links 44, and a second spool valve 80 for directing fluid to the remaining collapsible links 44. It is also within the scope of the invention that the first spool valve 78 and the second spool valve 80 can be. configured to direct fluid to the collapsible links 44 in a sequential manner, instead of two collapsible links 44 simultaneously, as shown in Figure 8. For instance, the fluid can be directed to none of the cylinders 18 initially, tben one of the cylinders 18, followed by two, then three, and finally all four. The first spool valve 78 and second spool valve 80 could also replaced with individual spool valves which can control fluid delivery to each cylinder 18 separately. In operation, the pulley 42 is in constant rotation because of the permanent connection between the pulley 42 and the crankshaft of the engine. This causes the camshaft 38 to be in constant rotation as well. As the camshaft 38 rotates, this causes the cams 40 to rotate, and apply force to the rollers 66 of the outer cylinders 48. When pumping action from the collapsible links 44 is necessary, the spool valves 78,80 remain in a position to prevent fluid flow through the fluid conduits 74, and the collapsible links 44 will be in the position shown in Figures 5 and 7. In this position, the spring 60 of the pin 52 will maintain the movable portion 58 of the pin 52 in the port 70 of the outer cylinder 48 and the collapsible link 44 will be in a first position or rigid non-telescoped configuration. Once in this first position, load will be transferred from the cam 40 to the roller 66, through the roller pin 68 to the outer cylinder 48, the pin 52, and to the inner cylinder 46. In this position, the inner cylinder 46 will compress the return spring 72 in a cyclical manner, and the return spring 72 will maintain contact between the cams 40 and the rollers 66.

As previously stated, the top plate 14 has openings 34 which are used for holding check valves 36. There are two openings 34, and therefore two check valves 36. for each cylinder 18. As pumping action is created by the cam 40 applying force to the rollers 66, each collapsible link 40 moves in one of the cylinders 18. Fluid is drawn into the cylinder 18 through one check valve 36 under low pressure, and forced out of the other check valve 36 under high pressure. Additionally, the inner cylinder 46 has a recess 54 which can be connected to a mechanical arm, which is then connected to a piston pump, or the recess 54 can be connected to a piston pump directly. The pumping action generated by the rotation of the camshaft 38 can have any number of applications.

When pumping action is not needed, either the first spool valve 78 or the second spool valve 80 can be moved into a position to allow fluid to flow through one of the fluid conduits 74 and apply pressure to one or all of the pins 52 in the inner cylinders 46. The fluid will flow through the fluid conduit 74, through the port 70 in the outer cylinder 48, into the aperture 50 in the inner cylinder 46 and apply pressure to the movable portion 58 of the pin 52. Once enough pressure is applied, the force applied to the movable portion 58 of the pin 52 will overcome the force applied from the spring 60, and the pin 52 will be in the position shown in Figure 6, and the moveable portion 58 of the pin 52 is no longer located in the port 70 of the outer cylinder 48. The load from the camshaft 38 is no longer transferred to the inner cylinder 46, and the collapsible link 44 is in a second position, or collapsible telescoped configuration. In this second position, the spring 62 between the bottom surface 64 of the outer cylinder 48 and the inner cylinder 46 acts to absorb the load from the outer cylinder 48. The return spring 72 maintains the inner cylinder 46 in a stationary position relative to the check valve 36, such that no fluid is pumped. Also, the position of the collapsible link 44 is in a position such that the pin 52 is aligned with the fluid conduit 74, and can be reactivated by releasing the fluid pressure. The collapsible link 44 is shown in a deactivated state in Figure 6.

The pump 10 can have all of the links 44 engaged, some of the links 44 engaged, or none of the links 44 engaged at any time. These various operating conditions can be used to create the necessary pumping action from the links 44 only when necessary.

The pumping action generated by the links 44 can be used to operate various auxiliary components in a motor vehicle. For instance, the links 44 could be used to supply hydraulic power to a power steering pump, an air conditioning unit, or any other type of auxiliary unit. The pump 10 could also be used for high-pressure fuel pumps, or fuel pumps for diesel engines having a common rail fuel injection system, or gasoline direct injection (GDI) spark- ignition engines which also utilize a common rail fuel injection system. It is also within the scope of the invention to use the pump 10 for non-automotive, general purpose hydraulic applications.

An alternate embodiment is shown in Figures 9-12. Referring to Figure 9, an alternate embodiment of a hydraulic pump according to the present invention is generally shown at 82. The pump 82 has a body 84, which has four rectangular-shaped sides 86, 88, 90, and 92 (as best seen in Figure 12), respectively, and two large square-shaped sides 94 and 96. The body 84 also has a series of cylinders 98, which can be positioned anywhere in the body 84 to achieve the required design objectives.

As can be seen in Figures 10-11, in this particular embodiment two cylinders 98 are placed along a first axis 100, with two more cylinders 98 placed along a second axis 102 with the first axis 100 being perpendicular to the second axis 102. The cylinders 98 are located on each rectangular- shaped side 86, 88, 90, and 92, and all terminate into an opening 104. The opening 104 is located in the body 84, at the center of the square-shaped sides 94 and 96. Located in each cylinder 98 is a collapsible link 106 similar to what is shown in the first embodiment having a first end 108 and a second end 110. For demonstrative purposes and clarity, only one collapsible link 106 is shown in the Figures. Also connected to each cylinder 98 is a fluid conduit 112 (best seen in Figure 11) which is used to deliver oil to actuate the collapsible links 106 in the cylinders 98.

Surrounding the body 84 is a housing 114, the housing 114 has four sections 116 which are connected to the body 84 through a series of fasteners (not shown) inserted through a corresponding series of holes 118 which pass through the housing 114. The fasteners could be a series of screws, rivets, or the like. Each section 116 of the housing 114 also includes openings 120, which receive check valves 36 in a similar manner to the first embodiment. Also, shown in Figure 11 are the sections 116 which have a series of oil feed pipes 122. The oil feed pipes 122 correspond to each of the fluid conduits 112 for delivering oil to the collapsible links 106 in a similar manner disclosed in the first embodiment. The opening 104 of the body 84 is suited for receiving a cam (not shown) having a lobe similar to the first embodiment. However, in this embodiment, the cam is positioned in the opening 104 and rotates about an axis perpendicular to the first axis 100 and the second axis 102. In operation, as the cam rotates, the first end 108 of each collapsible link 106 is depressed and released by the cam lobe in sequential manner and is pressed away from the opening 104. As the first end 108 is pressed and released, this causes each link 106 to create a pumping action which can be used to power devices in the vehicle requiring pumping actuation. The collapsible links 106 have two operating modes and are similar to the collapsible links 44 disclosed in the first embodiment. One operating mode is one in which the collapsible link 106 is in the first position, and another mode is one in which the collapsible link 106 is in the second position. Each collapsible link 106 has a pin 124 which is actuatable through the use of the fluid conduits 112. In operation, oil is fed through the fluid conduits 112 to actuate the pin 124. When the pin 124 is not actuated, the respective collapsible link 106 is in the first position and acts as a solid rigid non- telescoping member, facilitating the pumping action described above. The check valves 36 in the openings 120 will allow fluid to be drawn into the cylinder 98 under low pressure, and be forced out of the cylinder 98 under high pressure. When the oil supply in the fluid conduits 112 is used to release the collapsible link 106 for telescopic collapse, the collapsible link 106 is in the second position, and acts as a collapsed two-piece member, and does not generate any pumping action. It should be noted that the present invention is not limited to the embodiments described above. The pump 10 described thus far has included four cylinders 18 arranged linearly along the camshaft 38, as well as four cylinders 98 arranged circumferentially around a single cam in sequential manner. However, combinations of these arrangements are also within the scope of the present invention. It is also within the scope of the invention that the pump 10 can be driven directly or indirectly by the actual crankshaft of the engine, or the actual camshaft of the engine having an extra cam lobe. W

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Also, any number of the collapsible links 44 can be engaged or disengaged to vary the overall displacement of the pump 10. Along with varying the number of collapsible links 44 which can be engaged, the cylinders 18 can also vary in size, and can be of any size, further allowing the 5 pump 10 to be configured for any specific application. The cross-section of the inner members 46, the outer members 48, and cylinders 18 were shown having a round, cylindrical cross-section. It is within the scope of the present invention to modify the shape of the cross-section of the inner members 46, the outer members 48, and the cylinders 18 to have various shapes including, 0 but not limited to, an ellipse, an oval, a square, a rectangle, a triangle, a polygon an I-beam, a D-shape, or any other shape which is necessary to suit a particular application. Furthermore, any number of spool valves can be used any number of ways to activate any of the pumping chambers either individually or in any combinations to create any effective displacement. 5 The displacement of the pump 10 can also be changed as the pump 10 operates. The collapsible links 44 can be actuated from the first position to the second position, or from the second position to the first position quite rapidly, as frequently as once per revolution of the cam 40. This allows for the duty-cycle of each cylinder 18 to be varied, and therefore its displacement per 0 unit of time can also be varied. This feature of the present invention can eliminate the need for the pump 10 to have a conventional pressure regulator.

The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded5 as a departure from the spirit and scope of the invention.

Claims

CLAIMSWhat is claimed is:

1. A hydraulic pump, comprising: a body having one or more cylinders; at least one collapsible link, selectively actuatable to be in either a first position or a second position, said at least one collapsible link located in said one or more cylinders; and at least one cam operably associated with said body, and said at least one collapsible link, so rotation of said cam causes said at least one collapsible link to slidably move within said one or more cylinders when said at least one collapsible link is in said first position, and when said at least one collapsible link is in said second position, a portion of said at least one collapsible link is collapsed by engagement with said cam.

2. The hydraulic pump of claim 1, said at least one collapsible link further comprising: an outer member having a roller mounted on a roller pin, said roller operably associated with said cam; a port operably associated with a fluid conduit; and an inner member having an aperture for receiving a locking member, said inner member slidably disposed within said outer member.

3. The hydraulic pump of claim 2, said locking member further comprising: a base portion disposed within said aperture of said inner member; and a moveable portion selectively disposed within said aperture of said inner member or said port of said outer member, said moveable portion connected to said base portion, wherein fluid pressure is not applied to said moveable portion, a portion of said moveable portion of said locking member is disposed within said port in said outer member, rigidly connecting said outer member and said inner member, placing said at least one collapsible link in said first position, and when fluid pressure is applied to said moveable portion, said moveable portion slides into said aperture in said inner member such that no portion of said locking member is disposed within said port of said outer member, and said outer member and said inner member are not rigidly connected, placing said at least one collapsible link in said second position.

4. The hydraulic pump of claim 3, further comprising one or more fluid conduits operably associated with said body, wherein fluid is fed through said one or more fluid conduits, applying pressure to said locking member in said at least one collapsible link, causing said at least one collapsible link to be placed in said second position.

5. The hydraulic pump of claim 3, said inner member further comprising a recess for connecting said collapsible link to a device requiring pumping action.

6. The hydraulic pump of claim 3, wherein the cross-section of said inner member, said outer member, and said cylinder is one selected from the group consisting of a rectangle, an ellipse, an oval, a triangle, an I-beam, a D- shape, a circle, a semi-circle, a square, and a polygon.

7. The hydraulic pump of claim 3, wherein said locking member is one selected from the group consisting of a round pin, a disc, a square- shaped pin, or tube.

8. The hydraulic pump of claim 1, further comprising said at least one collapsible link automatically actuated to be in either said first position or said second position based on predetermined operating conditions of a motor vehicle, or from input from the operator of a motor vehicle.

9. The hydraulic pump of claim 1, wherein said at least one collapsible link is arranged linearly along said camshaft, circumferentially around said cam of said camshaft in sequential manner, or a combination thereof.

10. The hydraulic pump of claim 1, wherein said at least one collapsible link is operably associated with a piston used for pumping fluid, or with a mechanical arm of a pump.

11. A hydraulic pump operably associated with an engine, comprising: a body having one or more cylinders; a plurality of collapsible links located in said one or more cylinders, each of said collapsible links being actuatable between a rigid non- telescoping configuration and a collapsible telescoped configuration; a camshaft having a plurality of cams, said plurality of cams operably associated with each of said plurality of collapsible links; and said plurality of collapsible links are selectively actuatable such that when said camshaft rotates and said plurality of collapsible links are in said rigid non-telescoping configuration, pressure is selectively applied from said plurality of cams to said plurality of collapsible links, causing said plurality of collapsible links to generate a pumping action, and when said plurality of collapsible links are in said collapsible telescoped configuration, said plurality of collapsible links does not generate a pumping action when said camshaft rotates.

12. The hydraulic pump operably associated with an engine of claim 11, wherein said plurality of collapsible links are arranged linearly along the length of said camshaft, circumferentially around said plurality of cams of said camshaft in sequential manner, or a combination thereof.

13. The hydraulic pump operably associated with an engine of claim 11 , further comprising at least one of said plurality of collapsible links is operably associated with a piston used for pumping fluid.

14. The hydraulic pump operably associated with an engine of claim

11 , further comprising at least one of said plurality of collapsible links are operably associated with an arm connected to a pump.

15. The hydraulic pump operably associated with an engine of claim 11 , wherein the cross-section of said inner member, said outer member, and said cylinder is one selected from the group consisting of a circle, an ellipse, an oval, a square, a rectangle, a triangle, an I-beam, a semi-circle, a D-shape, and a polygon.

16. A method for providing auxiliary hydraulic pumping power from a camshaft, comprising the steps of: providing a body having one or more cylinders, and one or more fluid conduits; providing at least one collapsible link located in said one or more cylinders, said at least one collapsible link having a first position and a second position; providing a camshaft having at least one cam, said at least one cam operably associated with said at least one collapsible link; applying and releasing pressure to said at least one collapsible link by rotating said camshaft; selectively placing said at least one collapsible link in said first position or said second position through the use of fluid pressure applied from said one or more fluid conduits; causing said at least one collapsible link to create a pumping action when pressure is applied by said at least one cam to said at least one collapsible link when said at least one collapsible link is in said first position; and causing said at least one collapsible link to create no pumping action when pressure is applied by said at least one earn to said at least one collapsible link when said at least one collapsible link is in said second position.

17. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 16, further comprising the steps of: providing said at least one collapsible link to be further comprised of an outer member having a roller mounted on a roller pin, and a hole operably associated with said one or more fluid conduits, said roller operably associated with said cam; providing said at least one collapsible link to be further comprised of an inner member having a hole for receiving a locking member, operably associated with a device requiring pumping action, said inner member slidably disposed within said outer member; releasing fluid pressure from said locking member such that, a portion of said locking member is inserted into said port of said outer member, rigidly connecting said outer member and said inner member, forming said first position of said at least one collapsible link; and ^r applying fluid pressure to said locking member such that said locking member moves into said aperture in said inner member such that no portion of said locking member is disposed said port of said outer member, said outer member and said inner member are not rigidly connected, forming said second position of said at least one collapsible link.

18. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 17, further comprising the steps of: providing a cross-section of said outer member; providing a cross-section of said inner member; and slidably disposing said inner cylinder within said outer cylinder.

19. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 17, further comprising the steps of selecting the cross section of said inner member, said outer member, and said cylinder from the group consisting of a rectangle, an ellipse, an oval, a triangle, an I- beam, a D-shape, a circle, a semi-circle, a square, and a polygon.

20. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 25, further comprising the steps of: providing said inner member with a recess; connecting said collapsible link to said device requiring pumping action with said recess.

21. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 25, further comprising the steps of selecting said locking member from the group consisting of a round pin, a disc, a square- shaped pin, and a tube.

22. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 24, further comprising the step of actuating said at least one collapsible link into said second position by feeding hydraulic fluid through said one or more fluid conduits to apply pressure to said locking member.

23. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 24, further comprising the steps of providing said auxiliary hydraulic pumping power by arranging said at least one collapsible link linearly along said camshaft, circumferentially around said cam of said camshaft in sequential manner, or a combination thereof.

24. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 24, further comprising the step of providing said at least one collapsible link to be operably associated with a piston used for pumping fluid.

25. The method for providing auxiliary hydraulic pumping power from a camshaft of claim 24, further comprising the step of said at least one collapsible link to be operably associated with an arm of a pump.