Pivoting vane pump/motor

Abstract

An improved pivoting vane pump or motor with vane timing that minimizes friction by eliminating contact between the pressurizing vane 52a and the pressure surface, big seal 64 and produces constant pressure and volume outputs at a given rotational speed.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

A Provisional Patent Application was filed on Mar. 5, 2009, Application No. 61/209,405, Confirmation No. 9218 by Thomas P. Kadaja.

BACKGROUND OF THE INVENTION

This invention relates to pivoting vane hydraulic pumps and motors with vane timing.

U.S. Class:      418/268
Field of Search: 418/268, 418/266, 418/153, 418/39

References Cited

U.S. patent Documents

	4,762,480	September 1988	Winkler et al.
	4,846,638	August 1989	Pahl et al.
	5,163,825	November 1992	Oetting
	5,571,005	November 1996	Stoll et al.
	6,939,117 B2	September 2005	Wheeler et al.

BRIEF SUMMARY OF THE INVENTION

Currently there are two basic types of pivoting vane pumps or motors. The first has the pivoting vane pivoting at one end of the vane and the other has the pivoting vane pivoting near its center. Historically both types produced variable volume outputs and have the pressurizing vanes sliding on the inner housing surface creating friction and wear. In addition, these pumps/motors have circular inner housings surfaces providing sealing at only one point.

Most pivoting vanes pivot between two vane stops that limit the rotation of the vane. When the vane is resting on the rotor and it is closed is the first vane stop. The second vane stop limits the vane rotation when the vane is pressurizing, i.e., it is open. Unless a specific vane stop is created the vane stop becomes the circular inner housing surface, creating wear and friction.

Accordingly, the main object and advantage of this invention is to create a pivoting vane pump or motor with vane stops that produce a constant volume output, at a given speed, and increased mechanical efficiency, by reducing friction, in a cost-effective way. A new pivoting vane with a new housing performs these objects and advantages. This pump/motor minimizes friction because the pressurizing vanes do not contact the chamber wall. In addition, the clearances on this pump decrease with increased pressures allowing for greater pressures. Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.

DRAWING FIGURES

In the drawings, closely related figures have the same number but different alphabetic suffixes. A description of the first suffix describes the other suffixes.

FIG. 1 is an angled profile of a pivoting vane pump.

FIG. 2 is a side view of the pivoting vane pump illustrating section line 2-2.

FIG. 3 is an exploded view of the pivoting vane pump.

FIG. 4 illustrates the circular arcs and lines that make the pump inner chamber, the inner housing surface.

FIG. 5 illustrates the circular arcs and lines that make the vane.

FIG. 6 illustrates the circular arcs and lines that make the rotor.

FIG. 7 is a cross-section, from section lines 2-2 in FIG. 2, of the pivoting vane pump.

REFERENCE NUMERALS IN DRAWINGS

20    pump
22    case
24a-b cover
26    inlet
28    outlet
30    shaft
32a-h bolt
34a-h nut
36a-b flange
38a-b seal
40a-h bolt assembly
42
44a-b bushing
46    keyway
48    key
50a-c pin
52a-c vane
54    rotor
56    chamber
58    opening arc
60    closing arc
62    small seal
64    big seal
66a-b groove
68a-h case hole
70a-c cut
72a-b line
74a-c closed seal
76a-c vane pivot
78a-c pin holder
80
82a-c vane flat
84a-c pressure seal
86a-c rotor flat
88a-c pin housing
90a-c rotor pivot
92    rotor hole
94    rotor keyway

DETAILED DESCRIPTION OF THE INVENTION

There is no unique size for the pump and usually measures in inches, but a pivoting vane motor for hydroelectric production may be 10-20 feet in diameter. The pump rotates counterclockwise.

U.S. Pat. No. 4,762,480 is for a rotary pump with the pivot at one end of the vane. The pump has a circular housing and “a plurality of vanes pivotally mounted on the periphery of the rotor having free ends in sliding sealing contact with said bore,” from the ABSTRACT lines 11-13, This pump uses the housing surface for a vane stop.

U.S. Pat. No. 4,846,638 is on a rotary fluid machine with pivoting vanes that is used as a compressor or a pump. This patent also has the vane pivoting near the center of the vane and a cam action that is in effect a vane stop. The cam action opens and closes the vanes and allows for wear at both ends of the vane to compensate for wear on each other. Even with the cam effect, they are using the housing surface for a vane stop as stated in SUMMARY OF THE INVENTION, paragraph 3, lines 11-13 “The vanes are, thus, designed and positioned to automatically self compensate for frictional wear on the vanes.”

U.S. Pat. No. 5,163,825 is for an air or hydraulic motor with a vane stop specifically designed as a vane stop. In the DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS, first paragraph, lines 7-9, “These forces bring the tips of the vanes into contact with the inner cylindrical wall of the housing 12.” The vanes wear away and create a clearance and the vane stop prevents the clearance from increasing.

U.S. Pat. No. 5,571,005 is for a hinged vane rotary pump that has the vane hinged near the center of the vane and a circular housing with the vanes riding on the housing surface. This patent has a vane stop for closed vanes but not an open vane and consequently rides of the housing surface. As stated in the ABSTRACT, lines 9-11, “Preferably, stops are provided to limit movement of the vanes after maximum wear has occurred.”

U.S. Pat. No. 6,939,117 B2 is for a rotary apparatus that is both a hydraulic pump and motor. The ABSTRACT states, lines 9-11 “the gates form a seal against surface (22), of outer housing (16) and a retracted position in which the gates (20) lie substantially against surface (24) of the housing (12).” Claim 24 states, “The machine according to claim 23, wherein each socket and each gate is provided with a first set of respective stop surfaces that come into mutual abutment when the gates swing to the sealing position from the retracted position.”

FIG. 1 illustrates a typical embodiment of the present invention. A pump 20 has a cover 24a-b attached to a case 22 by a bolt 32a-h and a nut 34a-h. Cover 24a-b is circular in shape and has a flange 36a-b centered on it. Centered inside flange 36a-b is a seal 38a-b. Seal 38a-b prevents fluid leakage along a shaft 30 and the inside of flange 36a-b. A inlet 26 is a fluid passage to the interior chamber of pump 20. A outlet 28 is a fluid passage from the interior chamber of pump 20 to the exterior. Inlet 26 and outlet 28 have threads for connecting fluid lines, not illustrated. The pump/motor housing uses standard pump technology.

FIG. 2 is a side view of pump 20 illustrating section line 2-2.

FIG. 3 is an exploded view of pump 20. A bolt assembly 40a-h, consisting of bolt 32a-h and nut 34a-h, attach cover 24a-b to case 22. The interior surface of cover 24a-b is flat. Sea 138a-b fits inside, on the exterior side, of cover 24a-b. A bushing 44a-b fits inside of cover 24a-b and allows the rotation of shaft 30, a standard power shaft, with a keyway 46 and a key 48. A roller 50a-c is a cylindrical rod with a smaller radius in the middle of their length. Case 22 is flat with one half of the exterior being circular and the other half being square. A vane 52a-c and a rotor 54 fit inside case 22. The height of vane 52a-c and rotor 54 is slightly smaller, by the thickness of an oil film, than case 22. A groove 66b fits on the bottom half of case 22. Groove 66b is a shallow, and eighth or quarter of an inch in depth, and extents beyond outlet 28.

FIG. 4 is a side view of the arcs and lines that, when extruded; make the interior chamber surface, a chamber 56, of case 22. The lines from the center of chamber 56 lead to the endpoints of the various arcs and lines. The arc that makes a big seal 64 has an angle of about 130 degrees. The arc that makes a small seal 62 has an angle of about 50 degrees. The arcs of big seal 64 and small seal 62 have the same center but different radii. The radius of the arc of big seal 64 is slightly larger, by about a thousand of an inch, than the radius of the arc of a pressure seal 84a, shown in FIG. 5, when a vane 52a is open. Vane 52a in FIG. 7 illustrates an open vane. A vane 52c, in FIG. 7 illustrates a closed vane.

The arc of a opening arc 58 is tangent to the arc of big seal 64 and tangent to a line 72a, a line. The arc of a closing arc 60 is a mirror image, top to bottom, of the arc of opening arc 58. Line 72a is tangent to opening arc 58 and small seal 62. A line 72b is a mirror image of line 72a and is tangent to closing arc 60 and small seal 62. A groove 66a is approximately the same length, has the same center, but a slightly larger radius, as opening arc 58. A groove 66b is approximately the same length, and has the same center, with a larger radius, as closing arc 60. Groove 66b extends from about five degrees before the end of big seal 64 to a point near small seal 62 wherein vane 52a can close without trapping fluid.

FIG. 5 illustrates vane 52a and shows a side view of the arcs and line that make vane 52a-c. The arc of a closed seal 74a and small seal 62, in FIG. 4, has arcs that have same center when vane 52a is closed. Their diameters differ by a small clearance, usually the thickness of an oil film. Pressure seal 84a has the same center as big seal 64, in FIG. 4, when vane 54a is open. A vane pivot 76a has the same center as a rotor pivot 90a, in FIG. 6. Their diameters differ by the thickness of an oil film.

One end of the arc of vane pivot 76a is tangent to the arc of close seal 74a. The other end of the arc of vane pivot 76a ends at the line of vane flat 82a. The other end of vane flat 82a ends at pressure seal 84a. The arc of vane pivot 76a is not continuous because of a pin holder 78a. Pin holder 78a is a cylindrical cut centered on the edge and approximately midway on the length of vane pivot 76a. A heel 80a occurs at the intersection of closed seal 74a and pressure seal 84a. When vane 52a opens or closes, it rides on heel 80a preserving closed seal 74a and pressure seal 84a.

FIG. 6 is a side profile of the lines and arcs that make rotor 54. Rotor 54 is cylindrical in shape. A rotor pivot 90a is circular and tangent to the outer radius of rotor 54 and extends from a cut 70a to a rotor flat 86a. Rotor pivot 90a, b, c are spaced 120 degrees from each other. Cut 70a is a small section of material removed from rotor 54 and eliminates binding on vane 52a when it is open. A roller housing 88a is centered on the edge and located approximately halfway on the length of rotor pivot 90a. Each end of pin housing 88a has the same radius as roller holder 78a and roller 50a and the midsection of the arc is centered on the center of rotor pivot 90a and tangent to the ends. Rotor flat 86a is an end mill cut and located next to vane flat 82a when vane 52a is closed. Rotor 54 and closed vane 52a-c make a cylindrical shape. The center of rotor 54 has a rotor hole 92 that is slightly larger than shaft 30. A rotor keyway 94 is a keyway.

FIG. 7 is a cross section of pump 20 along section line 2-2 in FIG. 2 and illustrates how the various pump components connect together. Inlet 26 and outlet 28 connect to chamber 56 and to their respective fluid lines, not illustrated. Case 22 has holes, a case hole 68a-h, drilled into case 22. Case hole 68a-h accommodates their respective bolt 32a-h. Rotor 54 holds and positions pin 50a-c, shaft 30 and key 48, and allows vane 52a-c to pivot.

FIG. 7 illustrates pump 20 operations. An external power source rotates shaft 30. Shaft 30 has key 48 that holds and allows rotor 54 to rotate. Rotor 54 also holds and allows the rotation of vane 52a-c and roller 50a-c. Drag on the sides of vane 52a-c causes them to open. Starting with closed vane 52c, vane 52c slides on line 72a and opening arc 58 until it reaches the position of vane 52a. In the vane 52a position pressure seal 84a is parallel to, but not touching, big seal 64. Roller 50c has moved to the location of roller 50a. Roller 50a prevents vane 52a from opening too far and touching chamber 56 wall and is a vane stop. Roller 50a is attached to vane 52a and rotates in roller housing 88a. Vane 52a is in position to begin the 120-degree pressurizing cycle. Vane 52a is pressurizing fluid on the pressure side and drawing in fluid on the draw side.

When vane 52a reaches the position of vane 52b, the pressure/draw cycle is over. Vane 52b position has slid onto groove 66b. Groove 66b breaks the pressure seal and allows vane 52b to close without any pressure bias on one side. As the rotating vane 52b moves to the vane 52c position groove 66b allows vane 52b to close by allowing the fluid to escape. Groove 66a allows fluid to slide past vane 52a-c until the start of the pressure cycle.

Consequently only one vane 52a-c is pumping, for 120 degrees, at any time. When vane 52a-c looses pressure, the next vane 52a-c is in position to begin pressurizing and provides a constant output volume for pump 20.

Thus, the reader will see that the pivoting vane pump creates a highly efficient pump or motor. This efficiency stems from vane 52a-c not touching the big seal 64 when pressurizing fluid and having no pressure bias when opening or closing. Another advantage is that with increased pressure there will be a slight flexing of the vane, which will reduce vane/wall clearances even further.

The advantage of this invention is vane timing where only one vane produces pressure for 120 degrees and consists of the following three improvements.

• • First is a seal, big seal 64, that has an arc that has the same center as the arc of open vane 52a-c but their arcs have slightly different radii so they never make contact but still provide a seal.
  • Second, are groove 66a, b that allow vane 52a-c to open and close without pressure bias and sets the location where vane 52a-c begins and ends the pressure cycle.
  • Third is roller 50a-c that limits the rotation of vane 52a-c, the vane stop.

Consequently vane timing produces a pump or motor that operates at a given volume and pressure while minimizing friction. This contrast to earlier pivoting vane pumps that were continuously producing pressure that had variable volume and pressure outputs. Earlier pivoting vane pumps also had the vane sliding on the pressurizing surface that created more friction with increasing pressure.

The pivoting vane pump is the only positive displacement pump in the world that accommodates backpressure. Besides hydraulic pumps and motors, a multi-chambered pivoting vane pump makes a transmission for bicycles, tricycles, etc. The pivoting vane also makes gas compressors, for compressing air, etc. The pivoting vane motor also works as a water turbine for hydroelectric production.

While my description contains many specifications, these should not be construed as limitations on the scope of the invention, but rather as exemplification of one preferred embodiment thereof.

Accordingly, the scope of the invention should be determined not by the embodiments illustrated, but by the appended claims and their legal equivalents.

Claims

1. I claim: a pivoting vane pump or motor that utilizes vane timing.