TECHNICAL FIELD

The embodiments described below relate to fuel control valves and,

particularly, to fuel control valves for engines.

BACKGROUND

Fuel is mixed with air prior to combustion in a combustion chamber. The combustion generates heat that is converted into work. The work is typically converted into a rotary force or torque on a shaft in an engine. As long as the fuel-to-air mixture is not too high (not too rich), the amount of work produced by the combustion is proportional to the amount of fuel mixed with the air. The amount of fuel mixed in with the air can be controlled by a fuel injector. Many fuel injectors are constructed with a linearly reciprocating valve member. That is, the valve member reciprocates in a linear direction to open and close the valve. The valve member usually interfaces with a port or seat at one end of the reciprocal movement. The distance that the valve member is from the port is proportional to the fuel flow. The further the valve member is from the port, the greater the fuel flow. The closer the valve member is to the port, the lesser the fuel flow. When the valve member interfaces with the port, the fuel flow is zero.

Fuel injectors with linearly reciprocating members have some characteristics that limit their applications. For example, when the valve member presses against the port during the reciprocating movement, the valve member or the port can become deformed. Accordingly, over time, the valve member and port may provide an insufficient seal. The fuel flow rate can also be adversely affected by the deformed profiles on the port and valve members. In addition, the reciprocating movement of the valve member can cause undesirable vibrations in the valve and the engine. Mass inertia can also cause inaccuracies in the fuel flow rate. For example, higher cycling rates can require greater forces on the valve member to ensure that the timing and movement remains within specification. As a result, the mass inertia can limit the reciprocation rate of the valve members.

Accordingly, there is a need for a fuel control valve that does not require linearly reciprocating valve members. SUMMARY

A fuel control valve is provided. According to an embodiment, the fuel control valve comprises a housing with a bore fluidly coupled to a first fluid port and a second fluid port in the housing, a rotor rotatably disposed in the bore, and a motor that varies a rotation parameter of the rotor to control a fluid flow between the first fluid port and the second fluid port via a conduit in the rotor.

A method of forming a fuel control valve is provided. The method comprises forming a housing with a bore fluidly coupled to a first fluid port and a second fluid port in the housing, forming a rotor rotatably disposed in the bore, and forming a motor that varies a rotation parameter of the rotor to control a fluid flow between the first fluid port and the second fluid port via a conduit in the rotor.

A method of using a fuel control valve is provided. The method comprises providing a housing with a bore fluidly coupled to a first fluid port and a second fluid port in the housing, and rotating rotor rotatably disposed in the bore with a motor that varies a rotation parameter of the rotor to control a fluid flow between the first fluid port and the second fluid port via a conduit in the rotor.

A control system comprising is provided. The control system comprises a controller, a resolver electrically coupled to the controller and mechanically coupled to an engine, the resolver configured to determine the rotation potion of the engine, and a pressure control valve fluidly coupled to one or more fuel control valves and a fuel source.

ASPECTS

According to an aspect, a fuel control valve (100, 200, 300) comprises a housing (110, 210, 310) with a bore (118, 218, 318) fluidly coupled to a first fluid port (112,

212, 312) and a second fluid port (114, 214, 314) in the housing (110, 210, 310), a rotor (130) rotatably disposed in the bore (118, 218, 318), and a motor (120) that varies a rotation parameter of the rotor (130) to control a fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via a conduit (132) in the rotor (130).

Preferably, the motor (120) varies a rotation parameter during a single rotation cycle of the rotor (130). Preferably, the rotation parameter comprises a rotation speed of the rotor (130) and wherein the motor (120) increases the rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly coupled, and decreases a rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly decoupled.

Preferably, the rotation parameter comprises a rotation speed of the rotor (130) and wherein the motor (120) decreases the rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly coupled, and increases the rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly decoupled.

Preferably, the rotation parameter comprises a relative phase angle of the rotor (130) and the relative phase angle is a phase difference between a rotation position of the rotor (130) and a rotation position in an engine (10).

Preferably, the motor (120) continuously rotates the rotor (130) in a single direction for a rotation cycle of the motor (10).

Preferably, the motor (120) oscillates the rotor (130) in a rotation cycle of the motor (10).

Preferably, the motor (120) varies the rotation parameter of the rotor (130) via a spaced apart coupling comprised of a magnetic coupling and a spacer (125).

Preferably, the first fluid port (112) is fluidly coupled to a fuel source (5) and the second fluid port (114) is fluidly coupled to a combustion chamber (13) in an engine (10) via intake (12).

Preferably, the motor (10) controls a timing of the fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via the conduit (132) in the rotor (130).

Preferably, the motor (120) controls a duration of the fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via the conduit (132) in the rotor (130).

Preferably, the rotor (130) further comprises a rotor groove (134a-e) in the surface of the rotor (130) that is fluidly coupled to the conduit (132) and the first fluid port (112, 212, 312). Preferably, dimensions of the rotor groove (134a-e) are determined such that the rotation parameter of the rotor (130) corresponds to a desired fluid flow.

Preferably, the rotor (130) further comprises a outer rotor groove (134d,e) with dimensions selected to balance fluid pressures on the rotor (130) in an inner rotor groove (134a,b).

Preferably, the fuel control valve (100) further comprises a bushing (140, 640) concentrically disposed between the housing (110, 210, 310) and the rotor (130) wherein the bushing (140) has a first opening (144c) fluidly coupled to the first fluid port (112) and a second opening (144a,b) fluidly coupled to the second fluid port (114).

Preferably, the bushing (640) further comprises a groove (648a,b) that applies a fluid pressure to the rotor (130) to reduce a friction between the bushing (640) and the rotor (130).

Preferably, the bushing (140, 640) further comprises static seals (142, 642) between the bushing (140, 640) and housing (110, 210, 310) that prevent fluid flow from the first fluid port (112) and second fluid port (114).

According to an aspect, a method of forming a fuel control valve (100, 200, 300) comprises forming a housing (110, 210, 310) with a bore (118, 218, 318) fluidly coupled to a first fluid port (112, 212, 312) and a second fluid port (114, 214, 314) in the housing (110, 210, 310), forming a rotor (130) rotatably disposed in the bore (118, 218, 318), and forming a motor (120) that varies a rotation parameter of the rotor (130) to control a fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via a conduit (132) in the rotor (130).

Preferably, the first fluid port (112) is fluidly coupled to a fuel source (5) and the second fluid port (114) is fluidly coupled to a combustion chamber (13) in an engine (10) via intake (12).

Preferably, the motor (10) controls a timing of the fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via the conduit (132) in the rotor (130).

Preferably, the motor (120) controls a duration of the fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via the conduit (132) in the rotor (130). Preferably, the rotor (130) further comprises a rotor groove (134a-e) in the surface of the rotor (130) that is fluidly coupled to the conduit (132) and the first fluid port (112, 212, 312).

Preferably, dimensions of the rotor groove (134a-e) are determined such that the rotation parameter of the rotor (130) corresponds to a desired fluid flow.

Preferably, the rotor (130) further comprises a outer rotor groove (134d,e) with dimensions selected to balance fluid pressures on the rotor (130) in an inner rotor groove (134a,b).

Preferably, the method of forming the fuel control valve (100) further comprises a bushing (140, 640) concentrically disposed between the housing (110, 210, 310) and the rotor (130) wherein the bushing (140) has a first opening (144c) fluidly coupled to the first fluid port (112) and a second opening (144a,b) fluidly coupled to the second fluid port (114).

Preferably, the bushing (640) further comprises a groove (648a,b) that applies a fluid pressure to the rotor (130) to reduce a friction between the bushing (640) and the rotor (130).

Preferably, the bushing (140, 640) further comprises static seals (142, 642) between the bushing (140, 640) and housing (110, 210, 310) that prevent fluid flow from the first fluid port (112) and second fluid port (114) comprised of a magnetic coupling and a spacer (125).

According to an aspect, a method of using a fuel control valve (100, 200, 300), the method comprises providing a housing (110, 210, 310) with a bore (118, 218, 318) fluidly coupled to a first fluid port (112, 212, 312) and a second fluid port (114, 214, 314) in the housing (110, 210, 310), and rotating rotor (130) rotatably disposed in the bore (118, 218, 318) with a motor (120) that varies a rotation parameter of the rotor

(130) to control a fluid flow between the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) via a conduit (132) in the rotor (130).

Preferably, the motor (120) varies a rotation parameter during a single rotation cycle of the rotor (130).

Preferably, the rotation parameter comprises a rotation speed of the rotor (130) and wherein the motor (120) increases the rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly coupled, and decreases a rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly decoupled.

Preferably, the rotation parameter comprises a rotation speed of the rotor (130) and wherein the motor (120) decreases the rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly coupled, and increases the rotation speed of the rotor (130) while the first fluid port (112, 212, 312) and the second fluid port (114, 214, 314) are fluidly decoupled.

Preferably, the rotation parameter comprises a relative phase angle of the rotor (130) and the relative phase angle is a phase difference between a rotation position of the rotor (130) and a rotation position in an engine (10).

Preferably, the motor (120) continuously rotates the rotor (130) in a single direction for a rotation cycle of the motor (10).

Preferably, the motor (120) oscillates the rotor (130) in a rotation cycle of the motor (10).

Preferably, the motor (120) varies the rotation parameter of the rotor (130) via a spaced apart coupling.

According to an aspect, a control system (2000) comprises a controller (2010), a resolver (2030) electrically coupled to the controller (2010) and mechanically coupled to an engine (2030), the resolver (2030) configured to determine the rotation potion of the engine (2030), and a pressure control valve (2040) fluidly coupled to one or more fuel control valves (2050) and a fuel source (2060).

BRIEF DESCRIPTION OF THE DRAWINGS

The same reference number represents the same element on all drawings. It should be understood that the drawings are not necessarily to scale.

FIG. 1 shows a schematic view of an engine 10 according to an embodiment.

FIGS. 2a and 2b show the fuel control valves 100, 200 according to

embodiments.

FIG. 3 shows a cross sectional view of the fuel control valve 100 taken from section 3-3 in FIG. 1.

FIG. 4 shows a cross sectional view of the fuel control valve 100 taken from section 4-4 in FIG. 1. FIGS. 5a and 5b show cross sectional views of fuel control valves 200, 300.

FIG. 6a shows a perspective view of the rotor 130 and the bushing 140.

FIG. 6b shows a cross sectional side view of the rotor 130 and a bushing 640.

FIG. 7 shows an enlarged perspective view of the bushing 640.

FIGS. 8a and 8b show a perspective and a side view of the rotor 130.

FIGS. 9a and 9b show cross sectional end plan views of the fuel control valve 100 taken in FIG. 4.

FIG. 10 shows a layout view of the housing 110 to illustrate the fuel flow and pressures in the fuel control valve 100.

FIGS. 11 a- 11 f show the cross sectional end plan views of the housing 110 taken at 9a-9a in FIG. 4.

FIG. 12 shows a graph 1200 with plots representing the positions of the rotor 130 relative to a rotation in the engine 10.

FIG. 13 shows a graph with plots representing the positions of the rotor 130 relative to a rotation in the engine 10.

FIG. 14 shows a rotation rate graph 1400 with plots representing the rotation rate of the rotor 130 relative to the engine's 10 rotation position.

FIG. 15 shows a relative phase graph 1500 with plots showing the rotation of the rotor 130.

FIGS. 16a- 16c show oscillating rotation positions the rotor 130 and bushing 140 according to an embodiment.

FIG. 17 shows flow rate plot graph 1700 for the oscillating rotation positions of the rotor 130 and the bushing 140.

FIGS. 18a- 18c show cross sectional end views of the fuel control valve 100 according to an embodiment.

FIG. 19 shows a partial rotation graph 1900 of the fuel control valve 100 according to an embodiment.

FIG. 20 shows a schematic view of a control system 2000 that uses the fuel control valve 100-300 according to an embodiment. DETAILED DESCRIPTION

FIGS. 1 - 20 and the following description depict specific examples to teach those skilled in the art how to make and use the best mode of embodiments of a fuel control valve. For the purpose of teaching inventive principles, some conventional aspects have been simplified or omitted. Those skilled in the art will appreciate variations from these examples that fall within the scope of the present description. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the fuel control valve. As a result, the embodiments described below are not limited to the specific examples described below, but only by the claims and their equivalents.

As will be described in the following, the fuel control valve can operate with a continuous or an oscillator rotation. When the fuel control valve has a continuously rotating rotor, parameters such as open duration time and speed can be varied. Although the rotation speed of the rotor must correspond with the rotation speed of the engine, the speed within a single rotation cycle can be varied to control the fuel flow. In fuel control valves that have an oscillating rotor, rotation parameters such as rotation angle can be varied to control the fuel flow. For example, the rotation angle can be increased to increase the amount of fuel that flows through the valve during the oscillation. The fuel control valve is described in more detail in the following.

FIG. 1 shows a schematic view of an engine 10 according to an embodiment.

The engine 10 includes a fuel control valve 100. The engine 10 also includes a turbo 11 that is fluidly coupled to an intake 12. The fuel control valve 100 is coupled to the intake 12 and a fuel source S. Air flow is shown by the arrows in the intake 12. The arrow from the fuel control valve 100 to the intake 12 is the fuel that is mixed with the air in the intake 12. As can be seen, the air- fuel mixture enters a combustion chamber 13 that is disposed in a chassis 14. A connecting rod 15 is coupled to a piston 16 that moves reciprocally in the combustion chamber 13. Poppet valves 17i,e move in the combustion chamber 13 to allow the air- fuel mixture to enter the combustion chamber 13 and, after combustion, to exit the combustion chamber 13. A spark plug 18 is used to ignite the air-fuel mixture.

The ignition of the air- fuel mixture, the movement of the piston 16 and the valves 17i,e, and the flow of the fuel into the air flow in the intake 12 are synchronized. For example, the valves 17i,e are typically closed when the spark plug 18 ignites the air fuel mixture. The valves 17i,e coupled to the intake 12 is usually open when the fuel control valve 100 mixes fuel with the air in the intake 12. The piston 16 moves away from the valves 17i,e as the air- fuel mixture is provided to the combustion chamber 13. To move the piston 16 away from the valves 17i,e, the rod 15 moves in a reciprocating manner that is driven by a rotation in the engine such as a rotating crankshaft (not shown). The fuel control valve 100 can be synchronized with the rotation in the engine 10, as will be described in more detail in the following. The fuel control 100 can also be coordinated with a pressure control valve that controls the pressure of the fuel supply S. The pressure of the fuel can be reduced to, for example, reduce the fuel flow through the fuel control valve 100 for the rotation parameter.

FIGS. 2a-2b show the fuel control valves 100, 200 according to embodiments. As can be seen, the fuel control valves 100, 200 includes a housing 110, 210 that are coupled to a motor 120. The housing 110, 210 includes a first fluid port 112, 212 and a second fluid port 114, 214. The fuel control valve 200 is similar to the fuel control valve 100 but also includes a check valve 250. Fuel can enter the first fluid port 112, 212 and flow towards the second fluid port 114, 214. The motor 120 can vary a rotation parameter in the fuel control valve 100, 200 to control the fluid flow from the first fluid port 112, 212 to the second fluid port 114, 214. The second fluid port 114, 214 can be fluidly coupled to the intake 12 described with reference to FIG. 1. The motor 120 can control the fuel flow such that the fuel flow is synchronized with the engine 10.

FIG. 3 shows a cross sectional view of the fuel control valve 100 taken from section 3-3 in FIG. 1. The housing 110 includes an injection line 116 that fluidly couples a bore 118 with the second fluid port 114. The housing 110 also includes an end cap 111. A rotor 130 is rotatably disposed in the bore 118. As shown, the rotor 130 is also rotatably disposed in a bushing 140 that surrounds the rotor 130. The bushing 140 is coupled to the bore 118. The motor 120 is coupled to the rotor 130 via a motor magnet 124 and a rotor magnet 126 although any suitable coupling may be employed. The motor magnet 124 and the rotor magnet 126 comprise a spaced apart coupling. For example, in the embodiment shown, the motor magnet 124 and the rotor magnet 126 are magnetically coupled via a spacer 125. The spacer 125 prevents fluid from leaking from the bore 118. In the bore 118 are thrust bearings 160a,b that are coupled to the distal ends of the bushing 140. The thrast bearings 160a,b are also proximate the distal ends of the rotor 130.

FIG. 4 shows a cross sectional view of the fuel control valve 100 taken from section 4-4 in FIG. 1. The fuel control valve 100 is shown with the items described with reference to FIG. 3. Also shown is the first fluid port 112. As can be seen, the first fluid port 112 is fluidly coupled to the bore 118. A bearing supply port 113 is fluidly coupled to a balancing conduit 115 that balances pressures on the distal ends of the bushing 140. The bushing 140 and the thrust bearings 160a,b are shown as coupled to the housing 110 with screws. The screws prevent the rotation of the bushing 140 and the thrast bearings 160a,b.

FIGS. 5a and 5b show cross sectional views of fuel control valves 200, 300. FIG. 5a is taken from section 5a-5a in FIG. 1. FIG. 5b shows an alternative embodiment of the fuel control valve. Similar to the fuel control valve 100, the fuel control valve 200, 300 includes injection lines 216, 316 that fluidly couples a bore 218, 318 with the second fluid port 214, 314. A rotor 130 is rotatably disposed in the bore 218, 318. In the embodiments shown, the rotor 130 is rotatably disposed in a bushing 140. The bushing 140 is coupled to the bore 218, 318. The housing 210, 310 also includes an end cap 211, 311. The motor 120 is coupled to the rotor 130 via a motor magnet 124, 324, and a rotor magnet 126, 326, although any suitable coupling may be employed. The motor magnet 124, 324 and the rotor magnet 126, 326 comprise a spaced apart coupling. For example, in the embodiment shown, the motor magnet 124, 324 and the rotor magnet 126, 326 are magnetically coupled via a spacer 225, 325. The spacer 225, 325 prevents fluid from leaking from the bore 218, 318. In the bore 218, 318 are thrast bearings 260a,b, 360a,b that are coupled to the distal ends of the bushing 140. The thrust bearings 260a,b, 360a,b are also proximate the distal ends of the rotor 130.

Referring to FIGS. 4-5b, the housing 110-310 is shown as surrounding the rotor 130 and the bushing 140. The housing 110-310 also includes the end cap 111-311 to cover and retain the rotor 130 in the bore 118-318. The bore 118-318 is shown as a cylindrical bore although any suitable shapes can be employed. The bore 118-318 includes ridges that interface with O-rings on the bushing 140. These seals prevent the fuel from flowing along the bore 118-318. Accordingly, the fuel flows through the conduit 132-332. The fuel flow through the conduit 132-332 can be controlled by rotating the rotor 130 with the motor 120, as will be described in more detail in the following.

The motor 120 can be a stepper motor or any other appropriate motor. The motor 120 can rotate the rotor 130 with the spaced apart coupling. The motor 120 can also monitor the rotation angle of the rotor 130. For example, the motor 120 can include encoders the measures a rotation parameter such as, for example, the degrees of rotation of the rotor 130. Other rotation parameters can include the rotation speed and

acceleration. The rotation parameters can also be calculated from the measured rotation parameter. For example, the rotation speed can be calculated from the measured rotation angle of the rotor 130 over a period of time. Such calculations can be performed in the motor 120, a controller on the engine 10 or the like. By varying the rotation parameters, the fuel flow through the rotor 130 can be controlled by the motor 120. The rotor 130 and the bushing 140 include features that are used to control the fuel flow, as will be described with reference to FIGS. 6a-8b.

Still referring to FIGS. 4-5b, the fuel control valves 100-300 include the motor magnets 124,324 and the rotor magnets 126, 326 that couple the motor 120 to the rotor 130. As can be seen, in the fuel control valves 100, 200, the motor magnet 124 is partially surrounded by the spacer 125. In the fuel control valve 300, the motor magnet 324 partially surrounds the spacer 325 and the rotor magnet 326. A magnetic field is present between the motor magnet 124, 324 and the rotor magnet 126, 326 to couple the motor 120 with the rotor 130. Accordingly, the motor 120 can rotate the rotor 130 in the bushing 140.

The bushing 140 is held in place by the screws that traverse the thrust bearings 160a,b, 360a,b. The thrust bearings 160, 360 also enclose the rotor 130 and the bushing 140 to prevent linear movement of the rotor 130 and the bushing 140 within the bore 118. Preventing the linear movement of the rotor 130 and the bushing 140 with a common surface on the thrust bearings 160 can maintain the alignment of features between the rotor 130 and the bushing 140. This can ensure that the fuel flow through the fuel control valve 100-300 correlates with the rotation parameters. The features on the rotor 130 and bushing 140 are described in more detail in the following.

FIG. 6a shows a perspective view of the rotor 130 and the bushing 140. As can be seen, the rotor 130 is rotatably disposed in the bushing 140. The bushing 140 includes O-rings 142 concentrically arranged around the bushing 140. The bushing 140 also includes outer openings 144a,b and a center opening 144c. The outer openings 144a,b fluidly couple the rotor 130 with the second fluid port 114. The center opening 144c fluidly couples the first fluid port 112 with the rotor 130. The bushing 140 also has fuel grooves 146a-b that are fluidly coupled to the outer openings 144a,b.

FIG. 6b shows a cross sectional side view of the rotor 130 and a bushing 640. The bushing 640 can function as an air bearing that reduces the friction between the rotor 130 and the bushing 640. The bushing 640 includes O-rings 642 that are concentrically arranged around the bushing 640. The bushing 640 also includes outer openings 644a,b and a center opening 644c. The outer openings 644a,b fluidly couple the rotor 130 with second fluid port 114-314. The first opening 644c fluidly couples the first fluid port 112 with the rotor 130. The bushing 640 also includes bearing grooves 648a,b with openings (shown in FIG. 7). The bearing grooves 648a,b is adapted to apply a fluid pressure to the outer surface of the rotor 130. For example, as shown in FIG. 6b, the bearing grooves 648a,b are shown with Orings 642 disposed on the sides of the bearing grooves 648a,b. The Orings 642 provide a fluid seal that prevents fluid from flowing between, for example, the fuel groove 646a and the bearing groove 648a.

Accordingly, the fluid pressure in the bearing grooves 648a,b can be applied to the rotor 130 without leakage.

Also shown in FIG. 6b is a locking pin 647 that locks the rotor 130 in position.

The locking pin 647 can be installed in the rotor 130 and the bushing 140 to prevent the rotation of the rotor 130. In an alternative embodiment, the locking pin 647 can interface with an outer opening 132b. The locking pin 647 can be installed by, for example, the manufacturer of the fuel control valves 100-300. The rotation position of the rotor 130 is therefore known. Accordingly, an engine manufacturer can install the fuel control valve 100-300 on the engine 10 and set the initial relative rotation position of the rotor 130. Subsequently, the locking pin 647 can be removed from the rotor 130 to allow the rotor 130 to rotate when the engine 10 is powered up.

FIG. 7 shows an enlarged perspective view of the bushing 640. The bushing 640 is shown with a plurality of fluid openings 649 that are in the bearing grooves 648a,b. The fluid openings 649 extend from the bearing grooves 648a,b to the inner surface of the bushing 640. Fluid pressure that is in the bearing groove 648 is therefore applied to the outer surface of the rotor 130. Although a plurality of openings are employed, any appropriate number openings can be employed. The fluid pressure suspends the rotor 130 in a layer of fluid. The plurality of fluid openings 649 ensures that the fluid pressure surrounds the rotor 130. Accordingly, the rotor 130 is able to rotate within the bushing 140 without friction. In addition, the fluid pressure, when greater than the fuel supply S pressure, can prevent the fuel from leaking between the rotor 130 and the bushing 640.

FIGS. 8a and 8b show a perspective and a side view of the rotor 130. The rotor 130 is shown with the inner openings 132c-e in the rotor 130. Although not shown in FIG. 8, the rotor 130 also includes the outer openings 132a,b. The outer openings 132a,b extend from the rotor grooves 134a,b to the conduit 132. Similarly, a plurality of center openings 132c extend from the center rotor groove 134c to the conduit 132. A plurality of the center openings 132c can be sufficient to allow fluid flow between the first fluid port 112 and the second fluid port 114. On the opposing side of the rotor 130 are the outer rotor grooves 134d,e. The inner rotor grooves 134a,b have opposed outer rotor grooves 134d,e. This opposed configurations of the inner rotor grooves 134a,b and the outer rotor grooves 134d,e balances the pressures of the fuel on the rotor 130. The rotor 130 is therefore able to freely rotate to fluidly couple and decouple the conduit 132 with the ports 112, 114.

The rotor grooves 134a-e can be shaped so the conduit 132 is fluidly coupled and decoupled from the second fluid port 114. For example, the grooves surfaces 134as-es can include, as shown, recesses that can increase or reduce increase the volume of fluid flow between the rotor openings 132a-e. In alternative embodiments, the groove surfaces 134as-es can have a ramp shape that merges to the outer surface of the rotor 130. Additionally or alternatively, the length of the rotor grooves 134a-e can be different than the approximately 180° length shown.

FIGS. 9a and 9b show cross sectional end plan views of the fuel control valve 100 taken in FIG. 4. The housing 110 surrounds the rotor 130 and the bushing 140. The injection line 116 is fluidly coupled to the first bore portion 118a. The housing 110 also includes the center bore portion 118c. The first bore portionl 18a is sealed from the center bore portion 118c by the Oring 142 described with reference to FIG. 6a. In the cross section shown in FIG. 9a, the bore 118c supplies the fuel to the conduit 132. As can be seen, the fuel is supplied to the conduit 132 at all rotation positions of the rotor 130. This is due to the four center rotor openings 132c in the rotor 130 as well as the groove 134c in the circumference of the rotor 130. In alternative embodiments, more or fewer rotor openings can be employed.

The rotor 130 shown in FIG. 9b includes the groove 134a which extends about 180° along the circumference of the rotor 130. The length of the rotor groove 134a can determine the fuel flow through the housing 110. For example, in a single rotation of 360°, fuel can flow from the conduit 132 to the injection line 116 over 180° of the rotation. In alternative embodiments, the length of the rotor groove 134a can be more or less than 180°. For example, the length can be 120°. In addition, the rotor groove 134a is shown as having the same depth in the rotor 130. In alternative embodiments, the depth can vary to change the opening and closing fuel supply profile. The rotation of the rotor 130 and corresponding fuel flow is described in more detail in the following.

FIG. 10 shows a layout view of the housing 110 to illustrate the fuel flow and pressures in the fuel control valve 100. The bushing 140, 640 is not shown. In addition, only two openings to the fluid port 114 are shown although more or fewer can be employed. For example, alternative embodiments can employ four openings. The fuel control valve 100 is shown with arrows that depict fuel entering the fuel control valve 100 at the first fluid port 112. The rotation position of the rotor 130 is such that fuel entering the first fluid port 112 is fluidly coupled to the second fluid port 114. As can be seen, the fuel is in the conduit 132 which distributes the fuel to the rotor grooves 134a-e. The fuel in the inner rotor grooves 134d,e apply pressure to the rotor 130 that is approximately equal to the pressure in the outer rotor grooves 134a,b. The outer rotor grooves 134d,e have approximately same surface area and are opposite the inner rotor grooves 134a,b. Accordingly, the pressures on the rotor 130 result in no fluid force being applied to the rotor 130 that is transversal to the rotation axis X-X. In addition, the rotor grooves 134a-e are configured to result in net zero fluid pressure that is parallel to the rotation axis X-X. For example, the fuel pressures acting on the sidewalls of the rotor grooves 134a-e are balanced. Accordingly, the rotor 130 can have zero forces applied by the fluid in the housing 110.

Also shown is the bearing supply port 113 which supplies pressurized fluid, such as air, to the rotor 130 via the thrust bearings 160a,b. The pressurized fluid applies a fluid pressure at the distal ends of the rotor 130. The pressurized fluid can suspend the rotor 130 in the bushing 140 while the rotor 130 rotates. For example, the bearing supply port 113 can supply pressurized fluid to the thrust bearings 160a,b to form, for example, air bearings. The rotor 130 can therefore rotate without friction forces between the rotor 130 and the bushing 140. The rotation of the rotor 130 is described in more detail in the following.

FIGS. 1 la-1 If show the cross sectional end plan views of the housing 110 taken at 9a-9a in FIG. 4. To illustrate the rotation of the rotor 130, FIGS. 1 la-1 If show a zero rotation axis 1110 and a rotor rotation axis 1120. Also shown are arrows that illustrate the rotation of the rotor 130. The zero rotation axis 1110 is an exemplary zero degree rotation position of the rotor 130. The rotor rotation axis 1120 is an exemplary rotation position axis of the rotor 130. The rotation angle of the rotor 130 can be measured between the rotation axes 1110a,b. For example, FIG. 11a shows the rotor 130 rotated slightly less 0°. At this position, the conduit 132 is still fluidly decoupled from the bore 118a. As the rotor 130 rotates according to the arrows, the conduit 132 becomes fluidly coupled to the injection line 116. At the position shown in FIG. 1 lb, the conduit 132 is fully open to the injection line 116 and remains so through the rotation shown in FIGS. 1 lc,d. As can be seen in FIG. 11c, the rotor opening 132a is aligned with the bushing opening 142a at approximately 90° of rotation. As the rotor 130 continues to the position shown in FIG. l ie, the conduit 132 is fluidly decoupled from the injection line 116. In the position shown in FIG. 1 If, the rotation angle of the rotor 130 is 270°. As can also be seen, the rotor opening 132a is on the opposing side of the rotor 130 from the bushing opening 142a. The rotation position of the rotor 130 can be synchronized with a rotation in the engine 10, as will be described in more detail in the following.

Continuous Rotation of the Rotor

The following FIGS. 12-15 are related to a continuously rotating rotor 130. That is, the graphs show embodiments of the fuel control valve 100, 200, 300 controlling the fuel flow with a continuously rotating rotor 130.

FIG. 12 shows a graph 1200 with plots representing the positions of the rotor 130 relative to a rotation in the engine 10. The graph 1200 includes an engine rotation position axis 1210 that ranges from 0 to 720°. The graph 1200 also includes a magnitude 1220 to illustrate the relative positions of the rotor 130 and the rotation in the engine 10. The rotation position axis 1210 is divided into an intake portion 1210a, a compression portion 1210b, a power portion 1210c, and an exhaust portion 1210d. The graph 1200 also includes an engine rotation position wave form 1230. Also shown are a half speed plot 1240a, a same speed plot 1250a, and a double speed plot 1260a. The half speed plot 1240a shows the rotation of the rotor 130 relative to the engine rotation where the rotor 130 is synchronized to rotate at half the engine 10 rotation speed. The same speed plot 1250a illustrates the rotation of the rotor 130 when the rotor 130 is synchronized to rotate at the same engine 10 rotation speed. The double speed plot 1260a illustrates when the rotor 130 rotates at double the rotation speed of the engine 10.

Also shown are open rotation duration bars 1240b- 1260b. The first open duration bar 1240b shows that the conduit 132 is fluidly coupled to the injection line 116 while the engine 10 rotates from 0° to 180°. This can be due to the valve rotating at half the rotation speed of the engine. The second open duration bar 1250b shows that the rotor 130 is fluidly coupled to the injection line 116 for about 90° of the engine 10 rotation. This can be due to the rotor 130 rotating at the same speed as the engine 10. The third open duration bar 1260b shows that the conduit 132 is fluidly coupled to the injection line 116 for about 45° of the engine 10 rotation. This can be due to the conduit 132 rotating at half the rotation speed of the engine 10.

The foregoing described graph 1200 illustrates that changing the ratio of the engine 10 and rotor 130 rotation speeds changes not only the duration but also the timing of the fuel injection. For example, the first open duration bar 1240b shows that rotating the rotor 130 at half the speed results in the fuel being injected into the intake 12 only during the intake portion 1210a of the engine rotation. The second and third open duration bars 1250b, 1260b show that fuel can be injected into the intake 12 at other portions of the engine 10 rotation. For example, rotating the rotor 130 at double the speed of the engine 10 can result in short pulses of fuel being injected into the intake 12 in each portion 1210a-d of the engine rotation. In some applications it may be desirable to pulse the fuel injections rather than inject the fuel in only one of the four portions 1210a-d. Although the foregoing discusses the engine 10 rotation speed to rotor 130 rotation speed as an exemplary rotation position parameter, other rotation position parameters can be controlled by the motor 120, as will be described in the following.

FIG. 13 shows a graph with plots representing the positions of the rotor 130 relative to a rotation in the engine 10. The graph 1300 shows an engine rotation position axis 1310 that ranges from 0 to 720°. The graph 1300 also includes a magnitude axis 1320 to illustrate the relative positions of the rotor 130 and the rotation in the engine 10. Similar to the first graph 1200, the rotation position axis 1310 is divided into an intake portion 1310a, a compression portion 1310b, a power portion 1310c, and an exhaust portion 13 lOd. The graph 1300 also includes an engine rotation position plot 1340a. Also shown are a half rotation rate plot 1350a and open position bars 1340-1350.

The first open rotation duration bar 1340b shows that the conduit 132 is fluidly coupled to the injection line 116 while the engine 10 rotates from 0° to 180°. This can be due to the rotor 130 rotating at half the rotation speed of the engine 10. Also shown is a compressed open duration bar 1340c which shows that the conduit 132 is fluidly coupled to the injection line 116 when the engine 10 rotates from 30° to 150°. The compressed open duration bar 1350b can be due to the rotor groove have a shorter length. Accordingly, the timing of the opening is delayed and the closing is advanced. The rotation position parameter can therefore be the opening and closing timing of the rotor 130.

FIG. 14 shows a rotation rate graph 1400 with plots representing the rotation rate of the rotor 130 relative to the engine's 10 rotation position. The rotation rate graph 1400 includes a rotation position axis 1410 and a rotation rate axis 1420. The rotation position axis 1410 ranges from 0° to 360°. The rotation rate axis 1420 ranges from 0 to 120 units per second (unit scale of 100 is chosen for clarity). The graph 1400 includes a first rotation rate plot 1430 that is 180° out of phase with a second rotation rate plot 1440. Also included is a third rotation rate plot 1450 that is 180° out of phase with a fourth rotation rate plot 1460. The rotation rate plots 1430-1460 show the rotation rate of the rotor 130 relative to the rotation position of the engine 10. In the exemplary graph 1400, the engine 10 rotates at 100 units per second.

The rotation rate plots 1430-1460 illustrate that the rotation rate of the rotor 130 varies within a single rotation cycle of the engine 10. For example, the first rotation rate plot 1430 show that the rotation rate of the rotor 130 increases to 110 units per second while the engine 10 is rotating from 0° to 180°. The engine 10 rotation rate remains at 100 units per second. The first rotation rate plot 1430 also shows that the rotation rate drops to 90 units per second while the engine 10 rotates from 180° to 360°. In alternative embodiments, the rotation rate can be different. For example, the third rotation rate plot 1450 shows that the rotation of the rotor 130 increases to about 105 units per second when the engine 10 rotates from 0°-180°. The second and fourth rotation rate plots 1430, 1450 show that the rotation rate of the rotor 130 can also decrease when the engine 10 rotates from 0° to 180°.

FIG. 15 shows a relative phase graph 1500 with plots showing the rotation of the rotor 130. The relative phase graph 1500 includes a rotation position axis 1510 and a magnitude axis 1520. The rotation position axis 1510 ranges from 0° to 720°. The magnitude axis 1520 ranges from -20 to 30. The graph 1500 shows an engine rotation plot 1530 and rotation plots 1540a-1560a of the rotor 130. The graph 1500 also shows open duration bars 1540b- 1560b.

As can be seen, the rotation plots 1550a, 1560a are shifted by approximately 20°. For example, the first rotation plot 1540a is not shifted relative to the engine rotation plot 1530. Accordingly, the first rotation plot 1540a shows that the rotor 130 is rotating in phase with the engine 10. The second rotation plot 1550a is shown as shifted to the right of the graph 1500 by 20°. The 20° shift to the right of the graph 1500 shows that the rotation of the rotor 130 is delayed by 20° with respect to the first rotation plot 1540a. The third rotation plot 1560a is shown as shifted to the left of the graph by 20°. The 20° shift to the left of the graph 1500 shows that the rotation of the rotor 130 is advanced by 20° relative to the first rotation plot 1540a. The rotation shifts of the rotor 130 are also illustrated by the open duration bars 1540b- 1560b.

Shifting the rotor 130 rotation moves the relative phase of the open and close positions of the rotor 130. For example, the first open duration bar 1540b shows that the conduit 132 is fluidly coupled to the injection line 116 when the engine 10 rotates from 0° to 180°. The first open duration bar 1540b is not shifted relative to engine 10 rotation. The second open duration bar 1550b shows that the conduit 132 is fluidly coupled to the injection line 116 when the engine 10 rotates from 20° to 200°. The third open duration bar 1560b shows that the conduit 132 is fluidly coupled to the injection line 116 when the engine rotates from -20° to 160°. Accordingly, the motor 120 is able to vary the rotation parameter of the relative phase of the rotor 130 to control the fuel flow through the housing 110, 210.

The foregoing describes rotation parameters with respect to embodiments where the rotor 130 rotates continuously in a single direction. For example, the rotor 130 rotates continuously in the direction of the arrows shown in FIGS. 1 la- 1 If. Alternative rotations can be employed such as embodiments of oscillating rotations of the rotor 130 described in the following.

Oscillating Rotation of Rotor

FIGS. 16a-16c show oscillating rotation positions the rotor 130 and the bushing

140. As can be seen, the rotor 130 rotates between a closed position axis 1610 and an open position axis 1620. In the embodiment shown, the open position axis 1620 is about 60° from the closed position axis 1610. The open position axis 1620 corresponds to the fully open rotation position of the rotor 130. The rotor 130 is fully closed at the closed position 1630a shown in FIG. 16b. The fuel flow rate increases as the rotor 130 rotates from the closed position 1630a shown in FIG. 1 lb to the fully open position shown in FIG. 16c, as will be described in more detail in the following.

FIG. 17 shows flow rate plot graph 1700 for the oscillating rotation positions of the rotor 130 and the bushing 140. As can be seen, the flow rate graph 1700 includes a rotation position axis 1710 and a flow rate axis 1720. The rotation position axis 1710 ranges from 0° to 60°. The flow rate axis 1720 ranges from 0 to Q _max . Also shown in the graph 1700 is a flow rate plot 1730. The flow rate plot 1730 corresponds to the embodiment described with reference to FIGS. 16a-c. In the flow rate plot 1730 is a valve opening position 1730a and a fully open position 1730b. Between the valve opening position 1730a and the fully open position 1730b is a variable flow rate position 1740 denoted by φ _χ on the rotation position axis 1710. The corresponding variable flow rate Q _x is shown on the flow rate axis 1720. As can be seen, the valve opening position 1730a is at 30° and the fully opened position 1730b is at 60°. The flow rate plot 1730 is also linear between the valve opening position 1730a and fully open position 1730b. However, in alternative embodiments, the flow rate graph 1730 may be non-linear and end at different rotation angles, as will be illustrated in the following with reference to FIGS. 18a- 19.

FIGS. 18a-18c show cross sectional end views of the fuel control valve 100 according to an embodiment. The rotor 130 rotates in the bushing 140. Between a closed position axis 1810 and an open position axis 1820 is a rotation angle 1830a. As can be seen from FIGS. 18a-18c, the rotor 130 rotates in the bushing 140 between the rotated position 1830b and a closed position 1830c. In this embodiment, the rotor 130 does not fully rotate to the open position axis 1820. Accordingly, the fuel control valve 100 is not fully open. The max flow rate through the fuel control valve 100 is less than the flow rate when the fuel control valve 100 is fully open. The rotation position during the rotation is described in more detail in the following with reference to FIG. 19.

FIG. 19 shows a partial rotation graph 1900 of the fuel control valve 100 according to an embodiment. The partial rotation graph 1900 includes a time axis 1910 and a rotation position axis 1920. The rotation position axis 1920 ranges from 0 to 60°. Between 0 and 60° is a max rotation limit 1930. The partial rotation graph 1900 also includes a rotation position plot 1950 that shows the rotation position of the rotor 130 relative to time. The plot also includes a fully open line 1940 that corresponds to a fully opening rotation plot 1950'. As can be seen, the rotor 130 does not fully open along the rotation position plot 1950. The rotor 130 only reaches the max rotation limit 1930. In addition, the rotation position plot 1950 shows that the rotor 130 stops rotating during a wait state 1960. The rotation of the rotor 130 pauses during the wait state 1960. In addition, the rotation position plot 1950 also shows that the rotation oscillates with a time period 1970 that is measured between two peaks of the rotation position plot 1950.

FIG. 20 shows a schematic view of a control system 2000 that uses the fuel control valve 100 according to an embodiment. The control system 2000 includes a controller 2010 that is electrically coupled to a resolver 2030. The resolver 2030 is mechanically coupled to an engine 2020 and is configured to determine the rotation position of the engine 2030. Also included are fuel control valves 2050 that may be the same as the fuel control valves (100, 200, 300) described in the foregoing. A fuel source 2060 is fluidly coupled to the pressure control valves 2040. The pressure control valves 2040 are fluidly coupled to the fuel control valves. The fuel control valves 2050 are coupled to the engine 2020 and control fuel flow to cylinders in the engine 2020.

The controller 2010 is adapted to synchronize the rotation of the engine 2020 with the rotation parameter of the fuel control valves 2050. The controller 2010 can also coordinate the pressure control valves 2040 with the fuel control valves 2050. For example, the controller 2010 can control the fuel pressure valves 2040 to reduce the pressure of the fuel being supplied to the fuel control valves 2050. The reduction in fuel pressure can reduce the fuel flow rate through the fuel control valves 2050. Additionally or alternatively, the maximum rotation angle of an oscillating rotor 130 and the pressure can be reduced to reduce the fuel flow rate. The other rotation parameters can also be coordinated with the pressure control valves 2040. Accordingly, the fuel control valves 2050 can control the fuel flow.

In operation, the rotor 130 rotates in the bushing 140. The motor 120 can vary a rotation parameter of the rotor 130 to control the fluid flow between the ports 112-312, 114- 314 via a conduit 132 in the rotor 130. For example, the motor 120 can vary the rotation parameter during a single rotation cycle of the rotor 130. The rotation parameter can be a rotation speed of the rotor 130. The motor 120 can vary the rotation speed while the first fluid port 112-312 and the second fluid port 114-314 are fluidly coupled and decoupled. For example, the rotation speed of the rotor 130 can be increased while the ports 112-312, 114-314 are fluidly coupled to reduce the amount of fluid that flows between the ports 112-312, 114-314. The rotor 130 rotation speed can also be decreased while the ports are fluidly coupled to increase the amount of fluid the flows between the ports 112-312, 114-314.

The rotation parameter can also be the relative phase angle of the rotor 130. The relative phase angle can be the phase difference between the rotor 130 and the rotation in the engine 10. For example, the relative phase angle of the rotor 130 can be -20°. Accordingly, the fuel control valve 100-300 can inject fuel into the intake 12 before the engine 10 is in the intake portion of the engine 10 cycle.

The rotor 130 rotation can be continuous or oscillatory. For example the rotor

130 can oscillate between an open position and a closed position. The open position can be fully or partially open. Accordingly, the rotation parameter can be the rotation position of the opening position, closed position, and rate of oscillation of the rotor 130. The oscillation can also be varied, for example, by the rotation speed of the rotor 130. The oscillation can also pause when the rotor 130 has fluidly decoupled the ports 112- 312, 114, 314 to introduce a delay in the oscillation.

The embodiments described above provide a fuel control valve. As explain above the fuel control valve can control the fuel flow that is provided to the engine 10. While providing the fuel to the engine 10, the fuel control valve 100-300 can control a rotation parameter to control, for example, the flow rate of the fuel in a single rotation cycle of the engine 10. The fuel control valve 100-300 can control the fuel with a rotation motion rather than linearly oscillating motion found in prior art fuel injectors. Accordingly, the material in the fuel control valves 100-300 may be deformed. The fuel control valve 100-300 can also have less vibration than the prior art fuel injectors with linearly oscillating valve members.

The detailed descriptions of the above embodiments are not exhaustive descriptions of all embodiments contemplated by the inventors to be within the scope of the present description. Indeed, persons skilled in the art will recognize that certain elements of the above-described embodiments may variously be combined or eliminated to create further embodiments, and such further embodiments fall within the scope and teachings of the present description. It will also be apparent to those of ordinary skill in the art that the above-described embodiments may be combined in whole or in part to create additional embodiments within the scope and teachings of the present description.

Thus, although specific embodiments are described herein for illustrative purposes, various equivalent modifications are possible within the scope of the present description, as those skilled in the relevant art will recognize. The teachings provided herein can be applied to other fuel control valves, and not just to the embodiments described above and shown in the accompanying figures. Accordingly, the scope of the embodiments described above should be determined from the following claims.