TECHNICAL FIELD

[0001] This disclosure relates to pumps and, in particular, variable-output pumps suitable for automotive applications. BACKGROUND

[0002] Pumps are used in various automotive applications and are often driven by an external mechanical drive source, such as by a vehicle's engine (e.g., crankshaft). The pumps are typically driven at a fixed speed relative to the drive source (e.g., 1 : 1 ratio). This requires that pumps are sized according to worst-case scenarios, as pump output is a function of the drive speed. This results in pumps being oversized for most usage conditions and, thereby, operating suboptimally (e.g., inefficiently).

SUMMARY

[0003] Variable-output pumps are disclosed herein. In an implementation, a pump includes a pump housing, an outer ring member, an inner rotor, and an outer rotor. The housing includes an inlet and an outlet, and defines a first receptacle. The outer ring member is positioned in the first receptacle and is configured to be rotated therein by a second drive source in a first direction. The outer ring member defines a second receptacle. The inner rotor is configured to be rotated in the second receptacle by a second drive source in a second direction opposite the first direction. The outer rotor is positioned in the second receptacle and is arranged radially between the inner rotor and the outer ring member. The outer rotor is rotatable by the inner rotor and by the outer ring member. Relative rotation of the inner rotor creates therebetween a low pressure region that is in fluidic communication with the inlet and a high pressure region that is in fluidic communication with the outlet. Rotation of the inner rotor relative to the pump housing in the second direction at a first speed while the outer ring member is stationary relative to the pump housing results in a first pump output level from the outlet. Rotation of the outer ring member in the first direction simultaneous with rotation of the inner rotor in the second direction at the first speed results in a second pump output level that is greater than the first pump output level. [0004] Additionally, when the outer ring member is rotated, the low pressure region and the high pressure region may rotate with the outer ring member relative to the pump housing. Further, the outer ring member may include a low pressure passage extending from the second receptacle through an axial end face thereof, and a high pressure passage extending from the receptacle through the axial end face at a radial position that is different from the low pressure passage. The pump housing may also include a first circumferential channel in fluidic communication with the low pressure passage of the outer ring member and the inlet, and a second circumferential channel in fluidic communication with the high pressure passage of the outer ring member.

[0005] In an implementation, a pump includes a rotor, an inner housing, and an outer housing. The rotor includes a plurality of vanes and is rotatable by a first drive source in a first direction. The inner housing includes an inner cavity in which the rotor is rotatable by the first drive source to produce two low pressure regions and two high pressure regions. The inner housing is rotatable by a second drive source in the first direction to decrease output of the pump and a second direction opposite the first direction to increase output of the pump. The outer housing includes an outer cavity in which the inner housing is rotatable by the second drive source. The inner housing may also include two radial channels that remain in communication with an inlet of the outer housing and the two low pressure regions as the inner housing is rotated. The inner housing may also include a circumferential channel that remains in communication with an outlet of the outer housing and the two high pressure regions as the inner housing is rotated. The rotor may be rotatably supported by the inner housing. The inner housing may be rotatably supported by the outer housing.

[0006] In an implementation, a variable-output pump includes a housing, a rotor, and a rotatable ring. The housing includes an inlet and an outlet. The rotor is rotatable within the pump housing in a first direction by a first drive source. The rotatable ring is selectively rotatable within the pump housing in the first direction and a second direction by a second drive source, the second direction being opposite the first. The rotor is positioned within an inner cavity of the rotatable ring. Rotation of the rotatable ring in the first direction decreases output of the variable-output pump and in the second direction increases output of the pump.

[0007] These and other aspects of the present disclosure are disclosed in the following detailed description of the embodiments, the appended claims and the accompanying figures. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The present disclosure is best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not to-scale. On the contrary, the dimensions of the various features are arbitrarily expanded or reduced for clarity.

[0009] FIG. 1 is a schematic view of a pump according to an exemplary embodiment.

[0010] FIG. 2 is a perspective view of the pump shown schematically in FIG. 1.

[0011] FIG. 3 is a cross-sectional view of the pump shown in FIG. 1.

[0012] FIG. 4 is a top view of the pump shown in FIG. 1.

[0013] FIG. 5 is a partial view of the pump of FIG. 1 shown without a cover.

[0014] FIG. 6 is a partial view of the pump of FIG. 1 as shown in FIG. 5 with an inner rotor and an outer rotor thereof shown in phantom (i.e., dashed lines).

[0015] FIG. 7 is a partial view of the pump of FIG. 1 shown without the cover, the inner rotor, or the outer rotor; an outer ring member thereof is shown in phantom.

[0016] FIG. 8 is a partial view of the pump of FIG. 1 as shown in FIG. 7.

[0017] FIG. 9 is a partial view of the pump of FIG. 1 shown without the cover, the inner rotor, the outer rotor, or the outer ring member.

[0018] FIG. 10 is a perspective view of a pump housing of a pump assembly of the pump of FIG. 1 with hidden features shown in phantom.

[0019] FIGS. 11 A-l IE are partial perspective views of the pump of FIG. 1 depicting sequential movement of the inner rotor and the outer rotor as the inner rotor is rotated in approximate 90-degree increments in a clockwise direction.

[0020] FIGS. 12A-12E are partial perspective views of the pump of FIG. 1 depicting sequential movement of the outer ringer member and the outer rotor as the outer ring member is rotated in approximate 90-degree increments in a counterclockwise direction.

[0021] FIGS. 13A-13E are partial perspective views of the pump of FIG. 1 depicting sequential movement of the inner rotor, the outer rotor, and the outer ring member as the inner rotor is rotated in approximate 90-degree increments in a clockwise direction and as the outer ring member is rotated in a counterclockwise direction.

[0022] FIG. 14 is a partial exploded view of another embodiment of a pump.

[0023] FIG. 15 is a cross-sectional view of the pump of FIG. 14 taken along an axis of the pump as indicated by line 15-15 in FIG. 14. [0024] FIG. 16 is another cross-sectional view of the pump of FIG. 14 taken across the axis of the pump as indicated by line 16-16 in FIG. 15.

DETAILED DESCRIPTION

[0025] As shown schematically in FIG. 1, according to an exemplary embodiment, a pump 100 includes an inlet 102 (e.g., fluid inlet) and an outlet 104 (e.g., fluid outlet). The pump 100 is configured to be driven by a first drive source 1 10 and a second drive source 120. As discussed in further detail below, the first drive source 1 10 and the second drive source 120 are operated in a complementary manner, such that operation of the second drive source 120 may increase or decrease output of the pump 100 otherwise caused by the first drive source 1 10. Output of the pump 100 may, thereby, be adjusted or controlled relative to actual need and, thereby, increase efficiency.

[0026] The first drive source 1 10 is a mechanical drive source, such as an engine of a vehicle containing the pump 100. The first drive source 1 10 is configured as the primary drive source, which drives the pump 100 in a single direction at a fixed ratio. The second drive source 120 is configured as a secondary drive source to the first drive source 1 10 and drives the pump 100 bidirectionally and at variable speeds independently controlled from the first drive source 1 10. The first drive source 1 10 and the second drive source 120 are configured to drive internal pumping components relative to each other to achieve a net pump speed. Thus, while the speed of the first drive source 1 10 is dictated (e.g., based on engine speed) irrespective of required or optimal pump output, the direction and speed of second drive source 120 may be controlled independent of the first drive source 1 10 in direction and speed, so as to control the net pump speed and, thereby, control output of the pump 100 according to actual need or demand.

[0027] The pump 100 is configured as a gerotor pump (e.g., internal gear pump). As shown in FIGS. 2-10, the pump 100 includes a housing assembly 170 and various internal components contained within the housing assembly 170. The housing assembly 170 includes a pump housing 171, a motor housing 180, and a cover 190. The internal components include an inner rotor 130, an outer rotor 140, and an outer ring member 150. The inner rotor 130 may also be referred to as a rotor, an internal gear, or a drive gear. The outer rotor 140 may also be referred to as a rotor, an outer gear, an idler, or a driven gear. The outer ring member

150 may also be referred to as a rotatable ring or an inner housing. [0028] As illustrated in FIG. 4, rotation of the inner rotor 130 in a first direction (i.e., clockwise as shown) causes rotation of the outer rotor 140 in the same direction at a slower speed due to a differing number of teeth, as discussed in further detail below. This relative rotation creates a low-pressure region 102a (e.g., vacuum) and a high-pressure region 104a between the inner rotor 130 and the outer rotor 140. By increasing or decreasing the relative rotation between the inner rotor 130 and the outer rotor 140, output of the pump 100 may be increased or decreased. More particularly, the inner rotor 130 is rotatable by the first drive source 1 10 relative to the pump housing 171 (e.g., within the pump housing 171) in the first direction, which in turn rotates the outer rotor 140 in the first direction. The outer ring member 150 is configured to be rotated (e.g., is selectively rotatable) by the second drive source 120 relative to the pump housing 171 (e.g., within the pump housing 171) in the first direction or a second direction (i.e., counterclockwise as shown, or otherwise opposite the first direction), which in turn rotates the outer rotor 140 relative to the inner rotor 130 or changes the rate of rotation therebetween. Thus, by changing rotation of the outer ring member 150 in both direction and speed, the speed of relative rotation between the inner rotor 130 and the outer rotor 140 may be changed, so as to adjust the output of the pump 100. Rotating the outer ring 150 in the first direction by the second drive source 120 decreases output of the pump 100, while rotating the outer ring 150 in the second direction by the second drive source 120 increases output of the pump 100. For example, when rotating the inner rotor 130 relative to the pump housing 171 at a first speed in the first direction along with the rotation of the rotatable ring 150 relative to the pump housing 171 in the first direction may result in a first pump output level from the outlet 104 (e.g., flow rate, for example, expressed as CFM), while rotation of the rotatable ring 150 relative to the pump housing 171 in the second direction may result in a second output level that is greater than the first pump output level. Thus, by controlling the second drive source 120, the output of the pump 100 may be optimized through different usage conditions, regardless of the speed of the first drive source 1 10 (e.g., engine speed).

[0029] As shown in FIGS. 4-6, the inner rotor 130 of the pump 100 includes an input shaft 134 having a first axis 136 (e.g., central axis; illustrated with an X-shape in FIG. 4) and an outer periphery 132 defining a plurality of inner teeth 132a (e.g., inner or first teeth). The input shaft 134 is provided at a first end 130a of the inner rotor 130 and is configured to be coupled to the first drive source 1 10 to be rotated thereby. The plurality of inner teeth 132a are of substantially equal geometry (e.g., shape, size, etc.) and are spaced circumferentially equally about the first axis 136. [0030] In an axial direction beyond the input shaft 134 (e.g., in a region including the inner teeth 132a), the inner rotor 130 has a substantially constant cross-section extending along the first axis 136 to a second end 130b of the inner rotor. The second end 130b may form a substantially planar surface. The inner rotor 130 may, for example, be a unitary cast and machined metal component, or may be made according to other suitable processes, materials, and/or multiple subcomponents assembled together.

[0031] The outer rotor 140 of the pump 100 is configured in a complementary manner to the inner rotor 130, so as to receive the inner rotor 130 therein and to create the low-pressure region 102a and the high-pressure region 104a therebetween. More particularly, the outer rotor 140 includes an inner periphery 142 and an outer periphery 144, both of which are defined about a second axis 146 (e.g., central axis; illustrated with an X-shape in FIG. 4). The inner periphery 142 defines a plurality of outer teeth 142a (e.g., second teeth or lobes) that are spaced circumferentially equally about the second axis 146, while the outer periphery 144 is substantially circular. The plurality of outer teeth 142a are provided in a greater number than the plurality of inner teeth 132a (e.g., one greater). This results in the outer rotor 140 being rotatable relative to the inner rotor 130 (i.e., whether ultimately driven by the first and/or second drive sources 1 10, 120), such relative rotation creating the low-pressure region 102a and the high-pressure region 104a. The plurality of outer teeth 142a are of substantially equal geometry (e.g., shape, size, etc.), which is complementary to the geometry of the inner teeth 132a of the inner rotor 130.

[0032] The outer rotor 140 has a substantially constant cross-sectional shape extending along the second axis 146 thereof between first and second ends 140a, 140b of the outer rotor 140. The first and second ends 140a, 140b of the outer rotor 140 may form substantially planar faces thereof. The outer rotor 140 may, for example, be a unitary cast and machined metal component, or may be made according to other suitable processes, materials, and/or multiple subcomponents assembled together.

[0033] The inner rotor 130 of the pump 100 is received within the inner periphery 142 of the outer rotor 140, such that the plurality of inner teeth 132a of the inner rotor 130 are received between the plurality of outer teeth 142a of the outer rotor 140. Additionally, the first axis 136 of the inner rotor 130 extends parallel and offset to the second axis 146 of the outer rotor 140. As the inner rotor 130 is rotated by the first drive source 1 10 about the first axis 136, the inner teeth 132a successively engage the outer teeth 142a of the outer rotor 140 to rotate the outer rotor 140 about the second axis 146. This successive engagement between the inner teeth 132a with the outer teeth 142a creates the low-pressure region 102a (e.g., vacuum), as each inner tooth 132a of the inner rotor 130 moves away from the outer tooth 142a of the outer rotor 140 previously engaged therewith. This successive engagement also creates the high-pressure region 104a, as each inner tooth 132a of the inner rotor 130 moves toward the outer tooth 142a of the outer rotor 140 to be next engaged. The low-pressure region 102a is in fluidic communication with the inlet 102 of the pump 100, while the high- pressure region 104a is in fluidic communication with the outlet 104 of the pump 100. This creation of the low-pressure region 102a and the high-pressure region 104a functions to pump fluid through the pump 100.

[0034] As shown in FIGS. 4-8, the outer ring member 150 of the pump 100 is configured in a complementary manner to the outer rotor 140, so as to receive the outer rotor 140 therein and to rotate the outer rotor 140 relative to the inner rotor 130. The outer ring member 150 generally includes a pump end 152 (e.g., pump region) and a port end 162 (e.g., port region). The outer ring member 150 may, for example, be a unitary cast and machined metal component, or may be made according to other suitable processes, materials, and/or multiple subcomponents assembled together.

[0035] The pump end 152 of the outer ring member 150 is configured in a

complementary manner to the outer rotor 140, so as to receive the outer rotor 140 therein and to cause rotation of the outer rotor 140. The pump end 152 includes an inner periphery 154 and an outer periphery 156. The inner periphery 154 is substantially circular about the second axis 146 (i.e., of the outer rotor 140) and defines a receptacle 152b. The inner rotor 130 and the outer rotor 140 are positioned and rotate within the receptacle 152b with the outer rotor 140 being positioned radially between the inner rotor 130and the outer ring member 150. The inner periphery 154 is complementary in size to the outer periphery 144 of the outer rotor 140, so as to allow relative rotation therebetween, while also substantially inhibiting passage of fluid therebetween. The outer periphery 156 is substantially circular about the first axis

136. The pump end 152 has a substantially constant cross-sectional shape extending from an open end 158 of the outer ring member 150 to a substantially closed end of the pump end 152 of the outer ring member 150, which is formed by a first axial end face or wall 162a of the port end 162. The receptacle 152b may also be referred to as an inner cavity or a recess.

[0036] The first axial end wall 162a of the outer ring 150 receives thereagainst the second ends 130b, 140b of the inner and outer rotors 130, 140, respectively. The first axial end wall 162a is substantially planar, so as to correspond to the profile of the second ends 130b, 140b (also planar) of the inner and outer rotors 130, 140. The second ends 130b, 140b slide against the first axial end wall 162a as the inner and outer rotors 130, 140 are rotated relative to the outer ring member 150. This contact between the inner and outer rotors 130, 140 with the outer ring member 150 also substantially inhibits passage of fluid therebetween.

[0037] The port end 162 of the outer ring member 150 includes a low-pressure passage 164 and a high-pressure passage 166. The low-pressure passage 164 includes arcuate slot 164a and an aperture 164b extending through the first axial end wall 162a, which maintain fluidic communication between the inlet 102 and the low-pressure region 102a, such that the low-pressure region 102a draws fluid in through the inlet 102. This fluidic communication is maintained even as the outer ring member 150 is rotated relative to the housing assembly 170 (e.g., relative to the pump housing 171), as will be discussed in further detail below. The low-pressure region 102a and the high pressure region 104a may be in fixed position relative to the outer ring 150, but rotate with the outer ring 150 as the outer ring 150 rotates relative to the pump housing 171.

[0038] Similar to the low-pressure passage 164, the high-pressure passage 166 includes an arcuate slot 166a and an aperture 166b extending through the first axial end wall 162a, which maintain fluidic communication between the outlet 104 and the high-pressure region 104a, such that the high-pressure region 104a expels fluid through the outlet 104. This fluidic communication is maintained even as the outer ring member 150 is rotated relative to the housing assembly 170. The aperture 166b of the high-pressure passage 166 is positioned at a different radial position (e.g., radially outward), so as to be in fluidic communication with different circumferential ports 174a, 174b (e.g., a low-pressure circumferential port 174a and a high-pressure circumferential port 174b) of the pump housing 171, as discussed in further detail below. The circumferential ports 174a, 174b may also be referred to as circumferential channels.

[0039] As shown in FIGS. 7-10, the pump housing 171 of the housing assembly 170 is configured in a complementary manner to the outer ring member 150, so as to receive outer ring member 150 for rotation therein. The pump housing 171 generally includes a pump end 172 (e.g., pump region) and a port end 176 (e.g., port region). The pump housing 171 may, for example, be a unitary cast and machined metal component, or may be made according to other suitable process, materials, and/or multiple subcomponents assembled together. The pump housing 171 includes, or otherwise has coupled thereto, the inlet 102 and the outlet

104.

[0040] The pump end 172 of the pump housing 171 defines a receptacle 172a in which rotates the outer ring member 150. By containing the outer ring member 150, the receptacle 172a also contains therein the inner rotor 130 and the outer rotor 140. The receptacle 172a has an inner periphery 172b that is substantially circular about the first axis 136. The inner periphery 172b is complementary in size to the outer periphery 156 of the outer ring member 150 to allow rotation therein and to substantially inhibit passage of fluid therebetween. The pump end 172 extends between an open end 171a of the pump housing 171 and a closed end, which is formed by an axial end wall 176a of the port end 176. The pump end 172 has a substantially constant cross-sectional shape extending in the axial direction, thereby forming a cylindrical shape.

[0041] The port end 176 of the pump housing 171 is configured transfer fluid between the low- and high-pressure passages 164, 166 of the port end 162 of the outer ring member 150 with the inlet 102 and the outlet 104, respectively, of the pump 100. As shown in FIGS. 9-10, the port end 176 defines the low- and high-pressure circumferential ports 174a, 174b (e.g., first and second, inlet and outlet ports or channels). The low- and high-pressure

circumferential ports 174a, 174b are configured as circular channels that extend axially into the axial end wall 176a of the port end of the pump housing 171. The low- and high-pressure circumferential ports 174a, 174b are coaxial about the first axis 136 (e.g., concentric).

[0042] The low-pressure port 174a and the high pressure port 174b are configured to maintain or provide separate fluidic communication between the low- and high-pressure passages 164, 166 of the outer ring member 150 and the inlet 102a and the outlet 104a, respectively. This separate fluidic communication is maintained or provided even as the outer ring member 150 is rotated relative to the pump housing 171. As referenced above, the apertures 164b, 166b of the low- and high-pressure passages 164, 166, respectively, of the outer ring member 150 have different, non-overlapping radial positions and sizes. The low- pressure port 174a and the high-pressure port 174b have similarly non-overlapping radial positions and sizes, which are complementary to those of the apertures 164b, 166b of the low- and high-pressure passages 164, 166 of the outer ring member 150. Thus, since the low- and high-pressure circumferential ports 174a, 174b of the pump housing 171 are coaxial with the first axis 136 about which the outer ring member 150 rotates, the low- and high-pressure circumferential ports 174a, 174b of the pump housing 171 are maintained in communication with the apertures 164b, 166b of the low- and high-pressure passages 164, 166, respectively, of the outer ring member 150.

[0043] The low- and high-pressure ports 174a, 174b are separated by a first intermediate wall 174c, which is configured to maintain separate fluidic flow between the low- and high- pressure circumferential ports 174a, 174b. The first intermediate wall 174c extends to the same axial position as the axial end wall 176a, so as to engage a rear planar surface 150b of the first axial end wall 162a of the outer ring member 150 (see FIG. 3) to substantially prevent fluid transfer between the low and high pressure ports 174a, 174b.

[0044] The low- and high-pressure ports 174a, 174b are connected to the inlet 102 and the outlet 104 with low- and high-pressure conduits 175a, 175b (e.g., first and second fluid pipes, paths, etc.). The low- and high-pressure conduits 175a, 175b extend radially outward from the low- and high-pressure circumferential ports 174a, 174b to the inlet 102 and the outlet 104 of the pump 100, respectively. As shown in FIGS. 9-10, the low-pressure circumferential port 174a is arranged radially inward of and extends axially deeper than the high-pressure circumferential port 174b (i.e., away from the pump end 172 of the pump housing 171). This varied depth (e.g., staggered relationship) allows the low-pressure conduit 175a to be positioned further axially away from the pump end 172 and originate from a radially inward position, as compared to the high-pressure conduit 175b. The

varied/staggered depth of the low- and high-pressure circumferential ports 174a, 174b is also visible in FIG. 3. Alternatively, the low-pressure conduit 175a may be configured as a pipe or tube that extends through the high-pressure circumferential port 174b.

[0045] While the various low- and high-pressure features (e.g., ports, conduits, regions, etc.) have been discussed in particular spatial relationships described above, it should be noted that these spatial configurations may be altered (e.g., switched), as will be recognized by those skilled in the art.

[0046] The pump housing 171 may additionally be configured for the second drive source 120 to couple to and rotate the outer ring member 150 within the pump housing 171. As shown in FIGS. 9-10, the pump housing 171 additionally includes a central aperture 177, which is coaxial and concentric with the low- and high-pressure circumferential ports 174a, 174b. The central aperture 177 has received therethrough an output shaft 120a of the second drive source 120. The central aperture 177 may be divided or separated from the low- and high-pressure circumferential ports 174a, 174b with a second intermediate wall 178. As with the first intermediate wall 174c, the second intermediate wall 178 is axially coextensive (e.g., coplanar) with the axial end wall 176a and the first intermediate wall 174c, so as to engage the rear planar surface 150b of the outer ring member 150 and substantially prevent fluid flow therebetween (see FIG. 3).

[0047] As shown in FIG. 3, the connection between the outer ring member 150 and the output shaft 120a of the second drive source 120 may be a male/female relationship. For example, the outer ring member 150 may include a circumferential flange 150c extending axially from the rear planar surface 150b and form a receptacle that receives the output shaft 120a therein to form a splined or press-fit connection.

[0048] The motor housing 180 is configured to hold and/or form the second drive source 120. The second drive source 120 may, for example, be a 12V or a 48V electric motor. In 48V applications, the motor housing 180 may function as a stator of the electric motor, while the output shaft 120a is the direct output of the electric motor. In 12V applications, for example, or also 48V applications, the output shaft 120a may be coupled to a reduction gear (e.g., a ring gear; not shown), which is turn driven by an output shaft of the electric motor turning at a higher rate than the output shaft 120a (e.g., 10: 1 ratio).

[0049] Figs. 1 1 A-l IE, 12A-12E, and 13A-13E depict operation of the pump 100 in various manners, including relative rotation of the inner rotor 130, the outer rotor 140, and the outer ring member 150.

[0050] FIGS. 1 1 A-l IE illustrate operation of the pump 100 with rotation of the inner rotor 130 (i.e., by the first drive source 1 10) without any rotation of the outer ring member 150 (i.e., the second drive source 120 is not operating). FIGS. 1 1 A-l IE show successive approximate 90-degree turns of the inner rotor 130 in the clockwise direction. The inner rotor 130 is rotated by the first drive source 1 10, and in turn rotates the outer rotor 140. As the inner rotor 130 includes five teeth and the outer rotor 140 includes six teeth, the outer rotor 140 rotates at 5/6 of the rotational speed of the inner rotor 130. The outer ring member 150 is stationary relative to the pump housing assembly 170 (e.g., the pump housing 171), and may be held stationary by a positive coupling mechanism (not labeled) and/or by preventing movement of the second drive source 120. As the outer ring member 150 does not rotate relative to the pump housing 171, the low and high pressure regions 102a, 104a between the inner rotor 130 and the outer rotor 140 do not move relative to the pump housing 171. For brevity, reference numerals are omitted from FIGS. 1 lB-1 IE.

[0051] FIGS. 12A-12E illustrate operation of the pump 100 with rotation of the outer ring member 150 (i.e., by the second drive source 120) without any rotation of the inner rotor 130 (i.e., the first drive source 1 10 is not operating). FIGS. 12A-12E show successive

approximate 90-degree turns of the outer ring member 150 in the clockwise direction. The outer ring member 150 is rotated by the second drive source 120 relative to the pump housing

171 and in turn rotates the outer rotor 140. The inner rotor 130 remains stationary relative to the pump housing 171. Because the outer ring member 150 rotates relative to the pump housing 171, the low- and high-pressure regions 102a, 104a rotate therewith, while the apertures 164b, 166b of the low- and high-pressure passages 164, 166 remain in communication with the low- and high-pressure circumferential ports 174a, 174b of the pump housing 171. For brevity, reference numerals are omitted from FIGS. 12B-12E.

[0052] FIGS. 13A-13E illustrate operation of the pump 100 with rotation of the inner rotor 130 (i.e., by the first drive source 1 10) in the clockwise direction with rotation of the outer ring member 150 (i.e., by the second drive source 120) in the counterclockwise direction. With the inner rotor 130 rotating in the clockwise direction at a constant speed, the opposite directions of rotation results in increased pump output due to an increase in relative rotational speed between the inner rotor 130 and the outer rotor 140, as compared to only the inner rotor 130 being rotated with the outer ring member 150 remaining stationary. FIGS. 13A-13E show successive approximate 90-degree turns of the inner rotor 130. Because the outer ring member 150 rotates relative to the pump housing 171, the low- and high-pressure regions 102a, 104a between the inner rotor 130 and the outer rotor 140 also move relative to the housing 171. For brevity, reference numerals are omitted from FIGS. 13B-13E.

[0053] Referring to FIGS. 14-16, according to another embodiment, a pump 200 is a rotary vane pump (e.g., balanced vane pump) that is driven by a first drive source (not shown) and a second drive source 220. As with the pump 100 (refer to FIG. 1 above), the first drive source and the second drive source 220 are operated in a complementary manner, such that operation of the second drive source 220 may increase or decrease output of the pump 200 otherwise caused by the first drive source. Output of the pump 200 may, thereby, be adjusted or controlled to increase efficiency according to a desired or requested pump output rather than being dictated by the first drive source. The pump 200 may additionally be operated by only the second drive source 220 (e.g., when the first drive source is powered off).

[0054] The pump 200 generally includes a rotor 230 having vanes 230a, an inner housing 250, and an outer housing 270. The rotor 230 is positioned within the inner housing 250, which is in turn positioned within the outer housing 270. The rotor 230 is rotatable in single direction (e.g., in the first direction indicated by a curved arrow in FIG. 16) by the first drive source within and relative to both the inner housing 250 and the outer housing 270. For example, the rotor 230 may be rotatably coupled to a drive shaft 234 (e.g., via a splined connection). The drive shaft 234 is in turn coupled to and rotated by the first drive source

(e.g., a vehicle engine or other drive source of the vehicle), such as with a sprocket 234a and a chain (not shown). The inner housing 250 may be rotated in two directions (indicated by another curved arrow in FIG. 16) by the second drive source 220 within and relative to the outer housing 270 and also relative to the rotor 230. Construction and operation of the pump 200 is discussed in further detail below. The inner housing 250 may also be referred to as a rotatable ring or as an outer ring member. The outer housing 270 may also be referred to as a pump housing.

[0055] The inner housing 250 generally includes a first inner housing structure 252 (e.g., base or cover structure or member) and a second inner housing structure 254 (e.g., plate or cap structure or member), which cooperatively define an inner cavity 256a' in which the rotor 230 is positioned and rotates. The inner housing 250 is also configured to rotate within and relative to the outer housing 270. The inner housing 250 is additionally configured to route fluid into and out of the inner cavity 256a' from an inlet 270a and to an outlet 270b of the outer housing 270 (e.g., the outer housing 270 includes, or is otherwise coupled to, the inlet 270a and the outlet 270b) as discussed in further detail below. The inner cavity 256a' may also be referred to as a receptacle or a recess.

[0056] The first inner housing structure 252 generally includes a base portion 252a, a circumferential portion 252b, and a radial portion 252c. The first inner housing structure 252 may, for example, be a unitary or multi-component metal, composite, or polymer structure. The base portion 252a of the first inner housing structure 252 forms a bottom or first end or side of the inner housing 250. The base portion 252a of the first inner housing structure 252 may additionally include an extended portion 252a' (e.g., boss or extension), which protrudes from the base portion 252a in an axial direction. The extended portion 252a' engages a bearing 272' of the outer housing 270 to be rotatably supported thereby. The extended portion 252a' also includes an aperture through which the drive shaft 234 extends and is able to rotate relative thereto (e.g., may have an additional bearing rotatably supporting the drive shaft 234).

[0057] The circumferential portion 252b of the first inner housing structure 252 is an annular portion that extends axially from the base portion 252a. The circumferential portion

252b defines (e.g., extends around) an intermediate cavity 252b' . The circumferential portion 252b has a circular outer periphery, which allows the inner housing 250 to rotate within an outer cavity 272a (e.g., recess) of the outer housing 270. The circumferential portion 252b additionally includes a plurality of apertures 252b" that are spaced apart in a circumferential direction. At least one of the apertures 252b" remains in fluidic communication with the inlet

270a of the outer housing 270, for example, due to the size and/or spacing thereof and/or with circumferential channel being arranged between the outer housing 270 and the

circumferential portion 252b of the first inner housing structure 252. [0058] The radial portion 252c (e.g., flange) of the first inner housing structure 252 extends radially away from the circumferential portion 252b, for example, to engage and be driven by the second drive source 220 (discussed in further detail below). The radial portion 252c has a substantially circular outer periphery that may include teeth.

[0059] The inner housing 250 additionally includes an inner assembly 256 (e.g., interior or stator assembly), which is configured with the rotor 230 to pump fluid through the pump 200. The inner assembly 256 includes an annular member 256a and a plate member 256b, which are received in the intermediate cavity 252b' of the first inner housing structure 252. The annular member 256a and the plate member 256b are coupled to and rotate with the first inner housing structure 252 and/or the second inner housing structure 254 (e.g., with pins 256d).

[0060] The annular member 256a defines the inner cavity 256a' in which the rotor 230 is positioned. More particularly, the annular member 256a has an inner peripheral surface that defines the inner cavity 256a' with an oblong cross-sectional shape (e.g., generally elliptical). As the rotor 230 is rotated therein, the vanes 230a slide along an inner peripheral surface of the annular member 256a and slide radially inward and outward relative to the drive shaft 234 to create low-pressure regions 202 and high-pressure regions 204. It should be noted that the low-pressure regions 202 and the high-pressure regions 204 are fixed in position relative to the inner housing 250, but change position relative to the outer housing 270 as the inner housing 250 is rotated therein. The plate member 256b is positioned against axial surfaces of the annular member 256a and the rotor 230 to substantially close one axial end of the inner cavity 256a' .

[0061] The inner assembly 256 is additionally configured to route fluid from the inlet 270a of the pump 200 (e.g., of the outer housing 270) into the inner cavity 256a' . More particularly, an outer periphery of the annular member 256a is smaller than an inner periphery of the first inner housing structure 252, such that a circumferential cavity 250b is formed therebetween, which is in communication with the plurality of apertures 252b" of the first inner housing structure 252 and, thereby, the inlet 270a. The inner assembly 256 additionally includes channels 256c, which are cooperatively defined by the annular member 256a and the plate member 256b, and communicate fluid radially inward from the

circumferential cavity 250b into the inner cavity 256a' to the low-pressure regions 202 thereof (discussed in further detail below). The channels 256c remain in fluidic

communication with the inlet 270a and the first and second low-pressure regions 202, for example, even as the inner housing 250 is rotated relative to the outer housing 270. The channels 256c may also be referred to as radial channels.

[0062] The inner assembly 256 additionally includes a seal 256e (e.g., gasket). The seal 256e forms channels (not shown) between the base portion 252a of the first inner housing structure 252 and the plate member 256b of the inner assembly 256, which communicate fluid from the high-pressure regions 204 of the inner cavity 256a' to radially inward regions of the rotor 230 and into slots of the hub in which the vanes 230a slide. The higher pressure is thereby communicated to radially inward ends of the vanes 230a to force the vanes 230a radially outward to engage the inner periphery of the inner cavity 256a' .

[0063] While the inner assembly 256 is discussed as comprising three separate components, the various components may be formed as a unitary portion of one or more of the other components and/or with other components of the inner housing 250.

[0064] The second inner housing structure 254 of the inner housing 250 is configured to couple to and/or engage the first inner housing structure 252 to cooperatively form the inner housing 250. The second inner housing structure 254 may additionally substantially or partially seal the inner cavity 256a' and the circumferential cavity 250b. The second inner housing structure 254 is additionally configured to route fluid out of the pump 200.

[0065] The second inner housing structure 254 is a plate-like member that is coupled to and rotates with the first inner housing structure 252, as well as the inner assembly 256. The second inner housing structure 254 includes a central protrusion 254a on an inner axial face thereof. The central protrusion 254a is shaped in a complementary manner (e.g., diameter) to the circumferential portion 252b of the first inner housing structure 252, so as to be received thereby and radially locate the second inner housing structure 254 relative to the first inner housing structure 252.

[0066] The second inner housing structure 254 is additionally configured to rotatably support the drive shaft 234. For example, the second inner housing structure 254 may include a recess 254a' on the inner axial face thereof, which has received therein the drive shaft 234 and may also include a bearing or bushing supporting the drive shaft 234.

[0067] The second inner housing structure 254 additionally includes a radial portion 254b (e.g., radial flange) that extends radially outward from the central protrusion 254a. On the inner axial face, the radial portion 254b engages the radial portion 252c of the first inner housing structure 252. The second inner housing structure 254 is thereby located axially relative to the first inner housing structure 252 to substantially or partially seal the inner housing 250. [0068] The second inner housing structure 254 is configured on an external face thereof to be supported by the outer housing 270 and/or to route fluid to the outlet 270b of the pump 200 (e.g., of the outer housing 270The second inner housing structure 254 includes a protrusion 254c (e.g., boss or extension) that is coaxial with the drive shaft 234 and is rotatably supported by a bearing 274' of the outer housing 270.

[0069] The second inner housing structure 254 additionally includes a circumferential channel 254d on the external face thereof, which remains in communication with the outlet 270b as the inner housing 250 is rotated relative to the outer housing 270. The circumferential channel 254d is in communication with the high-pressure regions 204 of the inner cavity 256a' with channels 254e that extend axially through the second inner housing structure 254.

[0070] The outer housing 270 generally includes a first outer housing structure 272 (e.g., base structure or member) and a second outer housing structure 274 (e.g., cover or top structure or member). The first outer housing structure 272 includes the inlet 270a of the pump 200. The first outer housing structure 272 also defines an outer cavity 272a in which the inner housing 250 and the rotor 230 are positioned and rotate. The first outer housing structure 272 additionally includes the bearing 272', which rotatably supports the extended portion 252a' of the first inner housing structure 252 and through which the drive shaft 234 extends.

[0071] The second outer housing structure 274 is coupled to the first outer housing structure 272 to substantially enclose and/or seal the inner housing 250 therein. The second outer housing structure 274 includes the outlet 270b of the pump 200. The second outer housing structure 274 additionally includes the bearing 274', which rotatably supports the protrusion 254c of the second inner housing structure 254.

[0072] The first outer housing structure 272 and the second outer housing structure 274 additionally cooperatively define a circumferential channel 272b in which the radial portion

252c of the first inner housing structure 252 and the radial portion 254b of the second inner housing structure 254 are positioned and rotate (e.g., slide) within. The circumferential channel 272b protrudes radially outward relative to the outer cavity 272a.

[0073] The second drive source 220 is configured to rotate the inner housing 250 relative to the outer housing 270. As referenced above and as discussed in further detail below, rotating the inner housing 250 adjusts output of the pump 200 otherwise caused by rotating the rotor 230 with the first drive source. The second drive source 220 includes an electric motor 222 having an output shaft 224. The output shaft 224 is configured as a pinion shaft that in turn engages and rotates a gear 226 (e.g., a reduction gear, such as a stepped reduction gear), which in turn engages the outer periphery of the radial portion 252c of the first inner housing structure 252. Thus, the inner housing 250 is rotated by the second drive source 220 at a reduced speed or rate relative to the output of the second drive source 220 via a reduction mechanism, such as the gear 226 or another type of reduction mechanism (e.g., chains or belts). The gear 226 is received within another cavity 272c of the first outer housing structure 272, which is radially offset from the outer cavity 272a thereof and at a common axial distance with the circumferential channel 272b. The output shaft 224 extends into the cavity 272c to engage the gear 226, while the electric motor 222 is coupled to the outer housing 270. The second drive source 120 of the pump 100 above may, for example, be configured as the second drive source 220 (e.g., including an electric motor 222 and the gear 226, which in turn engages the outer ring 150 or an intermediate member therebetween).

[0074] Referring to FIG. 16, the pump 200 is operated by rotating the rotor 230 with the first drive source and/or rotating the inner housing 250 with the second drive source. As the rotor 230 is rotated relative to the inner housing 250, the vanes 230a slide along (e.g., against) the inner peripheral surface of the annular member 256a of the inner assembly 256, which defines the inner cavity 256a' . The vanes 230a additionally slide radially inward and outward relative to the rotor 230, the vanes 230a being force outward by being in communication with the high-pressure regions 204 as discussed above.

[0075] As a result of the relative rotation between the rotor 230 and the inner housing 250 (particularly the annular member 256a), the low-pressure regions 202 and the high-pressure regions 204 are created, which function to draw in and expel fluid from the pump 200. As shown, the pump 200 is a balanced vane pump having two low-pressure regions 202 and two high pressure regions.

[0076] As noted above, the low-pressure regions 202 and the high-pressure regions 204 remain in a fixed position relative to the inner housing 250, even as the inner housing 250 is rotated but may rotate relative to the outer housing 270. The low-pressure regions 202 remain in communication with inlet 270a as fluid is drawn into the inlet 270a, through the apertures 252b" of the first inner housing structure 252 into the circumferential cavity 250b, then through the channels 256c into the low-pressure regions 202. The fluid is then compressed in the high-pressure regions 204 and expelled through the channels 254e, and then flows through the circumferential channel 254d of the second inner housing structure 254 to and through the outlet 270b of the pump 200.

[0077] When the inner housing 250 is rotated in the same direction as rotor 230, the relative rotational speed of the rotor 230 to the inner housing 250 is reduced, so as to reduce output of the pump 200. When the inner housing 250 is rotated in an opposite direction from the rotor 230, the relative rotational speed of the rotor 230 to the inner housing 250 is increased so as increased output of the pump 200. The inner housing 250 may also be held static, while the rotor 230 is rotated by the first drive source, which results in pump output being dictated by the speed of the first drive source. The inner housing 250 may be held static by the second drive source 220, for example, by friction thereof and/or by actively applying a counter-torque thereto. Similarly, the rotor 230 may be held static (e.g., when the vehicle engine is off), while the inner housing 250 is rotated by the second drive source 220 opposite to the normal direction of rotation of the rotor 230 to provide the pump 200 with a suitable output.

[0078] While the present disclosure has been described in connection with certain embodiments, it is to be understood that the present disclosure is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.

EMBODIMENTS

[0079] 1. A pump comprising:

a pump housing including an inlet and an outlet, and defining a first receptacle;

an outer ring member positioned in the first receptacle and configured to be rotated therein by a first drive source in a first direction, the outer ring member defining a second receptacle; and

an inner rotor configured to be rotated in the second receptacle by a second drive source in a second direction opposite the first direction;

an outer rotor positioned in the second receptacle and arranged radially between the inner rotor and the outer ring member, the outer rotor being rotatable relative to the pump housing by the inner rotor and by the outer ring member;

wherein relative rotation between the inner rotor and the outer rotor creates therebetween a low pressure region that is in fluidic communication with the inlet and a high pressure region that is in fluidic communication with the outlet;

wherein rotation of the inner rotor relative to the pump housing in the second direction at a first speed results in a first pump output level from the outlet, and rotation of the outer ring member in the first direction simultaneous with rotation of the inner rotor in the first direction at the first speed results in a second pump output level that is greater than the first pump output level.

[0080] 2. The pump according to embodiment 1, wherein as the outer ring member is rotated, the low pressure region and the high pressure region rotate with the outer ring member relative to the pump housing.

[0081] 3. The pump according to embodiment 2, wherein the outer ring member includes a low pressure passage extending from the second receptacle through an axial end wall thereof, and a high pressure passage extending from the second receptacle through the axial end wall at a radial position that is different from the low pressure passage;

wherein the pump housing includes a first circumferential channel in fluidic communication with the low pressure passage of the outer ring member and the inlet, and includes a second circumferential channel in fluidic communication with the high pressure passage of the outer ring member and the outlet, the second circumferential channel being concentric with the first circumferential channel.

[0082] 4. A pump comprising:

a rotor having a plurality of vanes and rotatable by a first drive source in a first direction;

an inner housing having an inner cavity in which the rotor is rotatable by the first drive source to produce two low pressure regions and two high pressure regions, the inner housing being rotatable by a second drive source in the first direction to decrease output of the pump and a second direction opposite the first direction to increase output of the pump; and

an outer housing having an outer cavity in which the inner housing is rotatable by the second drive source.

[0083] 5. The pump according to embodiment 4, wherein the inner housing includes two radial channels that remain in communication with an inlet of the outer housing and the two low pressure regions as the inner housing is rotated, and includes a circumferential channel that remains in communication with an outlet of the outer housing and the two high pressure regions as the inner housing is rotated.

[0084] 6. The pump according to embodiment 5, wherein the rotor is rotatably supported by the inner housing, and the inner housing is rotatably supported by the outer housing.