JP5184893B2 - Hydraulic hybrid powertrain system - Google Patents

Description

[Related applications]
This application claims priority based on provisional patent application No. 60 / 655,221 filed on Feb. 22, 2005.
The present invention relates generally to vehicle powertrain systems, and more particularly to hydraulic hybrid powertrain systems.

  For example, a so-called hybrid power train for an automobile generally refers to a power train that uses an auxiliary motor such as an electric motor or a hydraulic motor for driving the automobile in combination with an internal combustion engine. Hybrid powertrain systems, known as parallel hybrids, typically include a mechanical drivetrain (coupled to the internal combustion engine) and an auxiliary drivetrain (coupled to the auxiliary motor). These systems have the disadvantage of being heavy because they require double parts. A hybrid drive system, known as a series hybrid, eliminates the mechanical powertrain, drives the vehicle only with a hydraulic motor, and provides the hydraulic pressure required for the hydraulic motor using an engine. These systems are attractive because they potentially reduce weight and result in efficiency. Although the attractiveness of such a hydraulic hybrid powertrain system has been recognized, many efficiency challenges remain related to engine operation and control for hydraulic drive motors.

  Accordingly, it is desirable to provide a hydraulic hybrid powertrain system that can increase the overall efficiency of the hydraulic hybrid powertrain system.

The present invention is a hydraulic hybrid powertrain system that includes a power device that generates high-pressure fluid at the output, at least one drive motor that generates rotary motion from the high-pressure fluid, and at least one power device. And a mode selection means for selecting an operation mode of at least one drive motor, and a hydraulic hybrid powertrain system. The system is also connected to the power unit and at least one drive motor, and controls to control the operation of the at least one drive motor, and selectively operates to interrupt the flow of high pressure fluid to the at least one drive motor. And braking means.
The above and other advantages of the present invention will be readily apparent to those skilled in the art upon consideration of the accompanying drawings in the following description of the preferred embodiment.

  Referring to FIG. 1a, a hydraulic hybrid powertrain system according to the present invention is indicated generally at 10. As will be appreciated by those skilled in the art, the powertrain system 10 may be used in a variety of applications including, but not limited to, automobiles, boats, submarines, helicopters, etc. In the description, it is referred to as being installed in an automobile. The powertrain system 10 includes a power unit portion 11, a mode selector module 43, a control portion 59, and a power delivery portion 76.

  The power unit portion 11 of the powertrain system 10 includes an engine 12 that communicates with a fuel source 14. The engine 12 is a conventional internal combustion engine, a turbine engine, an electric motor driven by a battery or a fuel cell, or the like. The engine 12 selectively provides torque to a preferably variable displacement hydraulic pump / motor 16, the inlet side of which is supplied by a low pressure source 18 of hydraulic fluid and the outlet side is provided with a high pressure conduit 20. It is done. The hydraulic fluid is a fluid such as, but not limited to, water, hydraulic fluid, transmission fluid, or any compressible gas, and is within the scope of the present invention. The pump / motor 16 is described because the device functions alternately as a pump or a motor depending on the mode of the system 10, which will be described in detail later.

  The power unit portion 11 in the system 10 includes a plurality of accessory drives, including but not limited to a motor generator 22, an air conditioner compressor 24, and a heat pump 26. The motor generator 22 is connected to a power management module, which is connected to the battery pack 30. The heat pump 26 communicates with the heater core 32, and both the heat pump 26 and the heater core 32 communicate with the cooling water source 34 of the engine 12. The air conditioner compressor 24 communicates with the heat exchanger 36. The accessory drives 22, 24, 26 are preferably operated by electric motors or hydraulic motors, respectively. As a variant, the accessory drives 22, 24, 26 are selectively mechanically clutched to the engine 12. The accumulator 38 is in communication with the high pressure conduit 20 that is coupled to the outlet of the pump / motor 16. The accumulator 38 acts as a reservoir for high pressure hydraulic fluid, maintains high pressure within the system 10 and is filled with high pressure gas or the like (not shown) as will be appreciated by those skilled in the art.

  The throttle control module 40 receives an input signal from the compressor 24 of the air conditioner via a signal on the line 24a, receives an input signal from the power management module 28 via a signal on the line 28a, and accumulates via the signal on the line 38. An input signal is received from 38. Based on the input signals on lines 24a, 28a and 38a, throttle control module 40 provides an output signal on line 42 to control either or both of engine 12 and pump / motor 16, as described in detail below. The signals on lines 24a, 28a, 38a, 42 are electrical signals or mechanical feedback between various components and the throttle control module 40. The throttle control module 40 is any suitable mechanical or electrical device that controls the operation of the engine 12 and the pump / motor 16 based on one or more inputs.

  The mode selector module 43 includes a mode selection valve 44 and communicates with the high pressure conduit 20 by a high pressure input conduit 46. The mode selection valve 44 is preferably coupled to a transmission-like shift lever (not shown) and is "D" or drive position (best seen in FIG. 1a), "N" or neutral position (best seen in FIG. 1b). ), “R” or reverse position (best seen in FIG. 1 c), and “P” or parking position (best seen in FIG. 1 d). The mode selection valve 44 includes a low pressure input conduit 48 connected adjacent to the high pressure input conduit 46. The mode selection valve 44 includes a high pressure output conduit 50 and a low pressure output conduit 52 connected to both sides of the mode selection valve 44. Each position, P, R, N, D, of the mode selection valve 44 selectively aligns the internal portion of the position with the conduits 46, 48, 50, 52 and controls the flow direction of hydraulic fluid within the system 10. However, details will be described later. Although described as “input” and “output”, during operation, each conduit 46, 48, 50, 52 functions as an input or output depending on the operating condition of the system 10, which will be described in detail later.

  The conduits 50 and 52 are connected to the brake override device 54. The brake override device 54 includes a high pressure output conduit 56 and a low pressure output conduit 58 on both sides of the brake override device 54. The brake override device 54 has a first or normal position 54a and a second or override position 54b, which will be described in detail later.

  The control portion 59 includes a volume control valve 60 and is in communication with the high pressure conduit 20 by a high pressure input conduit 62. The capacity control valve 60 includes a low pressure input conduit 64 connected adjacent to the high pressure input conduit 62. The capacity control valve 60 includes a high-pressure output conduit 66 and a low-pressure output conduit 68 connected to both sides of the capacity control valve 60. The displacement control valve 60 is a valve in a floating position, and the accelerator 70 and the brake 72 are connected to guide the flow from the displacement control valve 60 to a plurality of cylinders 74a, 74b, 74c, and 74d. Accelerator 70 and brake 72 are preferably mechanically coupled to an accelerator pedal and a brake pedal (not shown), respectively. The brake 72 is coupled to the brake override device 54 via the connector 73. The displacement control valve 60 has a first position, that is, an acceleration position 60a, a second position, that is, a holding position 60b, and a third position, that is, a deceleration position 60c. Each position 60a, 60b, 60c of the displacement control valve 60 selectively aligns the internal portion of each position 60a, 60b, 60c with the conduits 62, 64, 66, 68, as best shown in FIG. Next, the flow direction of the hydraulic fluid to the cylinders 74a, 74b, 74c, 74d is controlled.

  The cylinders 74a, 74b, 74c, 74d are mechanically connected to the driving motors or traction motors 76a, 76b, 76c, 76d of the wheels of the respective vehicles via connectors 75a, 75b, 75c, 75d, respectively. (Power delivery portion 76). The motors 76a to 76d are preferably variable displacement motors. The positions of the connectors 75a to 75d are determined by determining the capacities of the motors 76a to 76d and connecting them with a swash plate cam as recognized by those skilled in the art. The high pressure output conduit 66 communicates with one side of a piston (not shown) in each cylinder 74a-74d, and the low pressure output conduit 68 communicates with the opposite side of the piston in cylinders 74a-74d. Although the illustrated system 10 includes a plurality of traction motors 76a, 76b, 76c, 76d, as will be appreciated by those skilled in the art, the use of only one motor is within the scope of the present invention. For example, when installing a single motor in an automobile, the output of the single motor is coupled to a differential gear, which is mechanically coupled to a pair of drive wheels. Each traction motor 76a, 76b, 76c, 76d has upper ports 77a, 77b, 77c, 77d and lower ports 78a, 78b, 78c, 78d. The direction of fluid flow through upper ports 77a-77d and lower ports 78a-78d determines the direction of motors 76a-76d. The feedback connector 80 extends between the capacity control valve 60 and the pistons of the cylinders 74a to 74d.

The one-valve bridge circuit 82 comprises a plurality of one-valves 84, 86, 88, 90 and is arranged similarly to a full-wave rectifier bridge, as best shown in FIG. The conduit 92 communicates with the inlet of the one-way valve 84 and the outlet of the one-way valve 86. The conduit 92 is in communication with the high-pressure output conduit 56. The conduit 94 communicates with the inlet of the one-way valve 86 and the inlet of the one-way valve 88. The conduit 94 is also in communication with a low pressure source 18 of hydraulic fluid. The conduit 96 communicates with the outlet of the one-way valve 88 and the inlet of the one-way valve 90. The conduit 96 communicates with the low pressure output conduit 58. The conduit 98 communicates with the outlet of the one-way valve 84 and the outlet of the one-way valve 90. Further, the conduit 98 communicates with the high-pressure conduit 20.
The pump / motor 16 and the motors 76a to 76d are preferably variable displacement pumps / motors, as shown in FIGS. As a modification, the pump / motor 16 and the motors 76a to 76d are variable displacement pumps / motors of vane type or piston type, or are constant displacement pumps / motors.

  Referring now to FIG. 4, the entire inner gear device according to the present invention is shown at 100. The device 100 is configured to operate as a motor or as a pump, as will be appreciated by those skilled in the art, but will be referred to as a motor in the following description of the invention. The inner gear motor 100 includes a hollow housing 102 having a base portion 104 and an end cap 106. Base portion 104 forms a recess or cavity 108 therein and is sized to receive first mandrel 110 and first piston member 112. The end cap 106 includes at least two ports 107 (only one is shown), preferably on both sides of the end cap 106, extending between an inner surface and an outer surface, respectively. One port 107 is connected to a high pressure portion of the fluid system, such as the high pressure conduit 20 of FIGS. 1a-1e, and the other port 107 is connected to a return line or fluid source, such as the fluid source 18 of FIGS. 1a-1e. Has been.

The first mandrel 110 forms an opening 114 that extends through the base portion 111, and includes a first outer flange 116, a plurality of spaced second outer flanges 118, and an upper surface 113 of the base portion 111. It is extended and extended from. The inner flange 120 extends upward from the base portion 111 of the first mandrel and is located adjacent to the opening 114. The first outer flange 116 is located adjacent to the opening 114. The second outer flange 118 is spaced from both the opening 114 and the inner flange 120. The first seal bushing 122 is sized to rotatably fit in the opening 114 and is preferably at a height substantially equal to the height of the base portion 111 in the first mandrel 110 to open the bushing 122. When disposed within the portion 114, the upper surface of the bushing 122 is substantially flush with the upper surface 113 of the base portion 111.
The outer gear 124 is substantially circular in cross section and is adapted to be placed on top of the upper surface 113 of the base portion 111, with the bent outer surface of the gear 124 being respectively on the bent inner surfaces of the outer flanges 116, 118. Adjacent. The outer gear 124 includes a plurality of teeth 126 formed on the inner surface thereof. When disposed on the top surface 113, the gear 124 is fixed axially between the outer flange 118 and the inner flange 120.

The inner gear 128 is substantially circular in cross section and includes a plurality of teeth 130 formed on the outer surface thereof to form an opening 132 therethrough. The teeth 130 operate by meshing with teeth 126 formed on the inner surface of the outer gear 124. The lower surface of the gear 128 extends into and rotates with the bushing 122, and when the motor 100 is assembled and operating, the teeth 130 cooperate with the corresponding teeth of the bushing 122, which will be described in detail later. The outer surface of each tooth 130 of the inner gear 128 is adjacent to the inner surface of the inner flange 120. The opening 132 is adapted to receive the free end of the drive shaft or output shaft 134 when the motor 100 is assembled. The inner gear 128 is fixed to the shaft 134 . The drive shaft 134 is rotatably supported by the end cap 106 by a bearing 135 such as a ball bearing or a roller bearing. The free end of the drive shaft 134 extends a predetermined distance beyond the top surface of the end cap 106 and serves as the output shaft of the motor 100.

The second piston member 136 is adapted to form an opening 138 in its inner portion and to be attached to the respective upper surfaces of the outer flanges 116, 118 of the first mandrel 110. Accordingly, the second piston 136 and the first piston 112 are attached to the upper surface and the lower surface of the lower mandrel 110, respectively.
The second mandrel 140 is adapted to be disposed in the opening 138 of the second piston member 136 and is formed with an opening 142 in its inner portion to receive the drive shaft. The second mandrel 140 includes a downwardly extending flange 144 that cooperates with the upwardly extending inner flange 120 of the first mandrel 110 when the motor 100 is assembled. The upper mandrel 140 includes a pair of bore holes 146 extending therethrough and communicates with the gears 122 and 124 during the operation of the motor 100.
The second seal bushing 148 includes a plurality of teeth 150 formed on the outer surface of the second seal bushing 148 and forms an opening 152 therethrough. The second seal bushing 148 receives the upper mandrel 140 in the opening 152 and is received and rotated with the outer gear 124 to cooperate with the teeth 150 of the bushing 148 when the motor 100 is assembled and operating. Details will be described later.

  When the motor 100 is assembled, the first mandrel 110 and the first piston 112 are disposed on the base portion 104 of the housing 102, the first seal bushing 122 is disposed on the mandrel 110, and the outer gear 124 is disposed on the mandrel 110. Be placed. The inner gear 132 and the second mandrel 138 are attached to the drive shaft 134, the respective teeth 126, 130 of the gears 132, 124 are rotatably meshed, and the inner gear 132 engages the first seal bushing 122. Assembled. The second piston 136 is attached to the upper surface of the mandrel 110, and the second seal bushing 148 is disposed on the second mandrel 138 and engages the outer gear 124. The downwardly extending flange 144 cooperates with the upwardly extending inner flange 120 to divide the interior of the outer gear into the inlet chamber and the outlet chamber of the motor 100, and the upper end cap 106 is attached to the base portion 104. And surrounds the housing 102. The flanges 120, 144 extend radially between the teeth 126 and 130 to form an inlet chamber on one side of the flange and an exhaust chamber on the other side of the flange.

  In operation, shaft 134 is coupled to a load (not shown) such as a vehicle wheel. Pressurized fluid is introduced from a fluid system, such as the high pressure conduit 20 of FIGS. 1 a-1 e, through one port 107 and is directed through the bore hole 146 to the inlet chamber side of the gears 124, 128 for meshing. Acting on the teeth 126, 130 rotates the gear and shaft, flows between the teeth to the discharge chamber and is discharged to the other port 107 through the other bore hole 146. The first seal bushing 122 provides a rotational seal between the inner gear 128 and the first mandrel 110, and the second seal bushing 148 provides a rotational seal between the outer gear 124 and the second mandrel 140. And ensure the integrity of the inlet and outlet chambers. The motor 100 according to the present invention requires only the seals 122 and 148 to maintain a fluid seal and operate the motor 100 efficiently.

The normal or default spatial relationship between the teeth 126, 130 of the gears 124, 128 is such that the teeth 126, 130 engage substantially all the axial regions of the teeth. In such a relationship, the motor 100 generates maximum volume flow or maximum output. The motor 100 according to the invention advantageously varies from its maximum capacity because the gear 124 is movable axially along the shaft 134. As the gear 124 moves toward the first mandrel 110, fewer axial regions of the teeth 126, 130 engage, thus reducing the volume flow or capacity of the motor 100.
When unit 100 is configured as a motor, an external source of pressure, eg, hydraulic fluid from an external hydraulic pump, or compressed air from an air compressor provides volumetric flow to port 107 and gears 124, 128 is rotated to generate an output torque on the shaft 134. As the pressure changes, the gear 124 moves along the axis of the shaft 134 and changes the output horsepower of the motor 100. The motor 100 is advantageously used to control the output speed under widely varying output loads, including but not limited to automobiles, turrets, large machines, earthworking machines, large well excavators, marine vessels. , Plantation equipment etc. are included.

When the unit 100 is configured as a pump and a driving force, such as the engine 12 of FIGS. 1 a to 1 e, the shaft 134 is rotated at a low speed or low torque, and the pump 100 outputs its output based on the internal pressure of the pump housing 102. By changing, it reacts to reduce the input speed or input torque. In this state, the output port 107 generates a high back pressure in the exhaust chamber, the gear 124 moves along the axis of the shaft 134, and the gear 124 is balanced or nearly balanced along continuous axis. It becomes the position. Thus, the pump 100 changes from a maximum output or capacity when the gear 124 is substantially adjacent to the upper mandrel 140 to a minimum capacity when the gear 124 is substantially adjacent to the lower mandrel 110. can do.

  Referring now to FIG. 5, the entire outer gear device according to the present invention is shown at 200. The device 200 is configured to operate as a pump or as a motor, as will be appreciated by those skilled in the art, but will be referred to as a pump in the following description of the invention for ease of explanation. The external gear pump 200 includes a hollow housing 202 having a first end cap 204 and a second end cap 206 joined by a body portion 208. Preferably, the first end cap 204 and the second end cap 206 are attached to the body portion 208 by a plurality of fasteners 210 such as, for example, high strength bolts. The main body portion 208 has a recess 212 formed therein.

The first gear 214 has a plurality of teeth 216 formed on the outer surface thereof, and the second gear 218 has a plurality of teeth 220 formed on the outer surface thereof and is disposed in the recess 212 of the housing 202. Is adapted to be. The teeth 216 and 220 of the respective gears 214 and 218 operate while meshing so as to be rotatable in the recess or the pump cavity 212 during the operation of the pump 200. The first gear 214 has a shaft 222 extending, and the second gear 218 has a stepped shaft 224 extended. The first gear 214 is fixed to the shaft 222, and the second gear 218 is fixed to the shaft 224 . The shafts 222 and 224 extend to the opposite side in the axial direction, and the shaft 224 is longer than the length of the shaft 222. The first seal sleeve 226 has internal teeth that receive the first gear 214, and the second seal sleeve 228 has internal teeth that receive the end of the second gear 218.

The plate attachment 230 includes a flange 232 extending downward and is attached to the flat upper surface of the first thrust plate 234. Preferably, the thrust plate 234 is attached to the attachment 230 by a plurality of fixtures 236 such as high-strength bolts. The free end of the shaft 222 extends through an opening formed in the attachment 230 and the thrust plate 234. The free end of the shaft 222 is rotatably fixed to the attachment 230 and the thrust plate 234 by a pair of nuts 238 and is rotatably supported by a bearing 240 such as a ball bearing or a roller bearing. The second seal sleeve 228 is received in a recess in the attachment 230 adjacent to the flange 232. When the shaft 222 is attached to the attachment 230 and the thrust plate 234, the gear 214 is attached to the housing 202 so as to be movable in the axial direction.

The second thrust plate 242 is attached to the upper surface 205 of the first end cap 204 by a plurality of fixtures 244 such as high-strength bolts. The plate 242 includes an opening for receiving the free end of the shaft 224 and a large opening for receiving and placing a first seal sleeve adjacent the top surface of the first end cap 204. The free end of the shaft 224 extends through the opening of the plate 242, is screwed into a pair of nuts 246 at steps, and is rotatably supported by a bearing 248 such as a ball bearing or a roller bearing. The bearing 248 is preferably disposed in a cavity 250 formed in the upper surface of the first end cap 204, while the nut 246 attaches the shaft 224 to the end cap on the lower surface opposite the upper surface 205. The free end of the shaft 224 extends a predetermined distance beyond the lower surface of the end cap 204 and acts as a drive or output shaft for the pump 200.
A first port 252 and a second port 254 are formed in the body portion 208 and extend between the inner surface and the outer surface, respectively. One port 252, 254 is connected to a low pressure portion of a fluid system such as the hydraulic fluid source 18 of FIGS. 1 a-1 e, and the other port 252, 254 is a fluid such as the high pressure conduit 20 of FIGS. 1 a-1 e. Connected to the high pressure or pressurized part of the system.

  In operation, the shaft 224 is coupled to a driving force such as the engine 12 of FIGS. 1a-1e. When the driving force rotates the shaft 224, the gear 218 rotates and the gear 214 rotates. Fluid is introduced into the fluid system through one port 252 or 254 and is trapped between meshing teeth 216 and 220 and discharged from the other port 252 or 254, as is well known to those skilled in the art. The Appropriate passages are formed in the housing 202 to ensure that the fluid is directed correctly during operation of the pump 200. The first seal sleeve 226 provides a rotational seal between the first gear 214 and the top surface 205, and the second seal sleeve 228 provides a rotational seal between the second gear 218 and the attachment 230. Providing and ensuring the integrity of the pump cavity 212. The pump 200 according to the present invention requires only seal sleeves 226 and 228 to maintain the seal and operate the pump 200 efficiently.

The normal or default spatial relationship between the teeth 216, 220 of the gears 214, 218 is such that the teeth 216, 220 engage substantially all the axial regions of the teeth. In such a relationship, the pump 200 generates a maximum volume flow or maximum capacity. The pump 200 according to the invention advantageously changes from its maximum capacity since the first gear 214 is movable in the axial direction . As the first gear 214 moves toward the lower thrust plate 242, the less axial region of the teeth 216, 220 engages, which reduces the volume flow or capacity of the pump 200. Typically, the motive force occurs when the shaft 224 rotates at a low speed or low torque, and the pump 200 reduces its input speed or input torque by changing its output based on the internal pressure of the pump housing 202. To react. In this state, the output port 252 or 254 creates a high back pressure in the recess 212, the first gear 214 moves along with the attachment 230 along the axis of the shaft 224, and the gear 214 is in continuous operation. The position along the axis is balanced or nearly balanced. Thus, the pump 200 changes from a maximum output or capacity when the gear 214 is substantially adjacent to the gear 218 to a minimum capacity when the gear 214 is substantially adjacent to the lower thrust plate 242. can do.

When the apparatus 200 is configured as a motor, an external source of pressure, eg, hydraulic fluid from an external hydraulic pump, or compressed air from an air compressor provides volumetric flow to ports 252 and 254, and gears The output torque is generated in the shaft 224 by rotating the 214 and 218. When the pressure changes, the first gear 214 moves along the axis of the shaft 224 and changes the output horsepower of the motor 200. The motor 200 is advantageously used to control the output speed under widely varying output loads, including but not limited to automobiles, turrets, large machines, earthmoving machines, large well excavators, ships , Plantation equipment etc. are included.
In operation of system 10, when engine 12 is started, torque is supplied to pump / motor 16, thereby supplying pressurized hydraulic fluid to high pressure conduit 20. The accumulator 38 maintains the hydraulic pressure within the conduit 20 relatively stable and provides energy conservation in a manner well known to those skilled in the art. The pressure in the conduit 20 is transmitted to the conduits 46, 62 and 98.

  Referring to FIG. 1a, when the mode selection valve 44 is in the D or drive position and the brake override device 54 is in the 54a position, hydraulic fluid flows through the conduit 46, through the mode selection valve 44, and into the D position. Exit the conduit 50 in the direction indicated by the arrow, pass through the brake override device 54, exit the conduit 56 in the direction indicated by the arrow 54a, and reach the upper ports 77a-77d of the motors 76a-76d, respectively. Reach the lower ports 78a-78d through motors 76a-76d, respectively, and reduce the pressure to provide forward output torque to each motor 76a-76d in a manner known to those skilled in the art. The low pressure hydraulic fluid in the lower ports 78a-78d passes through the conduit 58, through the brake override device, exits the conduit 52 in the direction of the arrow at position 54a, passes through the mode select valve 44, and passes through the arrow at the D position. Exit the conduit 48 in the direction of to the hydraulic fluid source 18.

  Referring to FIG. 1b, when the mode select valve 44 is in the N or neutral position and the brake override device 54 is in the 54a position, hydraulic fluid flows through the conduit 46 but adjacent to the N position conduit 46. The cap prevents flow through the mode selection valve 44. The output conduits 50, 52 are in communication with the low pressure hydraulic fluid in the conduit 48 so that no fluid flows to the brake override device 54 or the motors 76a-76d, and the pressure in the conduits 50, 56 is controlled by the conduits 52, 58. Balance with the pressure inside. When in the N position, if any motor 76a-76d requires oil flow, oil from reservoir 18 can flow to motors 76a-76d.

  Referring to FIG. 1c, when the mode selection valve 44 is in the R or reverse position and the brake override device 54 is in the 54a position, hydraulic fluid flows through the conduit 46, through the mode selection valve 44, and into the R position. Exits the conduit 52 in the direction indicated by the arrow, passes through the brake override device 54, exits the conduit 58 in the direction indicated by the arrow 54a, and reaches the lower ports 78a-78d of the motors 76a-76d, respectively. , Through the motors 76a-76d to the respective upper ports 77a-77d to reduce the pressure and provide the output torque in the reverse direction to the respective motors 76a-76d in a manner known to those skilled in the art. The low pressure hydraulic fluid in the lower ports 77a-77d passes through the conduit 56, through the brake override device, exits the conduit 50 in the direction of the arrow at position 54a, passes through the mode select valve 44, and passes through the arrow at the D position. Exit the conduit 48 in the direction of to the hydraulic fluid source 18.

  Referring to FIG. 1d, when the mode selection valve 44 is in the P or parking position and the brake override device 54 is in the 54a position, hydraulic fluid will not flow through any of the conduits 46, 48, 50, 52. Not because, in the P position, any flow through motors 76a-76d is blocked by the cap adjacent to each conduit 46, 48, 50, 52.

  As outlined above, the brake override device 54 in the first position 54a has hydraulic fluid between the conduits 50 and 56 and between the conduits 52 and 58 (depending on the position of the mode selection valve 44). Allow to flow in between. However, as best shown in FIG. 1e, in the second position 54b, hydraulic fluid does not flow through any conduits 50, 52, 56, 58 because the second position 54b. This is because the cap adjacent to the respective conduit 50, 52, 56, 58 prevents any flow through the brake override device 54. The brake override device 54 moves from the normal first position 54a to the second position 54b by the operation of the brake 72 and the transmission of a signal along the connector 73, and hydraulic fluid is transferred from the capacity control valve 44 to the motors 76a to 76b. The flow to 76d is prevented.

  In operation, when the mode select valve 44 is in the D or drive position, engagement of the brake 72 causes the override device 54 to move to the second position 54b and the only hydraulic fluid source of the motors 76a-76d is It is the source through the valve bridge circuit 82, so all fluid flow goes through the one-way valve bridge circuit 82. During braking, the motors 76a-76d begin to function as pumps and advantageously recover energy from the rotation of the vehicle wheels during braking. During braking in the D position, hydraulic fluid passes from hydraulic fluid source 18 through conduit 94, through one-way valve 86, through conduit 92, to upper ports 77a-77d, to motors 76a-76d, The pressure of the hydraulic fluid increases. High pressure hydraulic fluid flows from the motors 76a-76d, passes through the lower ports 78a-78d, through the conduit 96, and if the pressure in the conduit 96 is higher than the conduit 98, through the one-way valve 90 to the conduit 98. The high pressure hydraulic fluid flows into the conduit 20 and refills the accumulator 38.

  During braking when the mode select valve 44 is in the R position, hydraulic fluid passes from the hydraulic fluid source 18 through the conduit 94, through the one-way valve 88, through the conduit 96, and to the lower ports 78a-78d. Thus, the pressure of the hydraulic fluid rises to the motors 76a to 76d. High pressure hydraulic fluid flows from the motors 76a-76d, passes through the upper ports 77a-77d, through the conduit 92, and if the pressure in the conduit 92 is high compared to the conduit 98, through the one-way valve 84 to the conduit 98. Upon entering, the high pressure hydraulic fluid flows into conduit 20 and refills accumulator 38.

  On the other hand, the valve bridge circuit 82 prevents hydraulic fluid from flowing in the reverse direction to the motors 76a-76d once the vehicle is completely stopped. During braking when the mode selection valve 44 is in the D position, the brake override device 54 moves to the position 54b and blocks the flow from the mode selection valve 44 to the motors 76a to 76d. The flow from high pressure conduit 20 attempts to reach motors 76a-76d via conduit 98, but is blocked from flowing to the motor by valves 84,90. The one-valve bridge circuit 82 allows flow from the conduit 92 through the one-way valve 84 or from the conduit 96 through the one-way valve 90 to the conduit 98, which occurs for the conduits 56, 92 or the conduits 58, 96. Only if the pressure is higher than the pressure in conduit 98. If the pressure in conduit 92 is low compared to the pressure in conduit 98 and conduit 94, while valve 86 is open, there is no flow from reservoir 18 to conduit 92 because conduit 94 is at a low pressure. Similarly, if the pressure in conduit 96 is low compared to the pressure in conduit 98 and conduit 94, one-way valve 88 will open, but flow from reservoir 18 to conduit 96 will occur because conduit 94 is at a low pressure. Advantageously, high pressure hydraulic fluid prevents the motors 76a-76d from engaging in the opposite direction after the vehicle has completely stopped.

In operation, hydraulic fluid flow through the system 10 is controlled by an operator via an accelerator 70 and a brake 72 coupled to the displacement control valve 60. The connector 80 and the coupling portions 75a to 75d are coupled together by an appropriate link or the like, and provide feedback to the displacement control valve 60 via the coupling portions 75a to 75d to the motors 76a to 76d. This is the same way 80 provides control to motors 76a-76d via couplings 75a-75d.
For example, when a vehicle user (not shown) pushes the accelerator, the feedback connector 80 moves in the acceleration direction, and the displacement control valve 60 moves toward the position 60a. High pressure fluid from the conduit 62 flows through the port of the displacement control valve 60, increases the pressure in the conduit 66, and flows into the cylinders 74a-74d. Since the pressure in conduit 66 is higher than the pressure in conduit 68, connectors 75a-75d move in the acceleration direction, increasing capacity and thus increasing the output torque of motors 76a-76d.

Once the desired output torque of motors 76a-76d has been reached, motors 76a-76d move connectors 75a-75d in a decelerating direction to return the throttle, reducing the pressure in conduit 66 and reducing the pressure in conduit 68. Increase. This movement is transmitted to the displacement control valve 60 by the feedback connector 80, and moves the displacement control valve toward the position 60b. At position 60b, there is no flow through the capacity control valve, so connectors 75a-75d are kept stationary and the output torque of motors 76a-76d is kept constant with capacity.
When the user removes his or her foot from the accelerator 70, this causes the feedback connector 80 to move in the deceleration direction and the displacement control valve 60 to move toward position 60c. High pressure fluid from conduit 62 flows through the port of volume control valve 60, increasing the pressure in conduit 68 and flowing to cylinders 74a-74d. Since the pressure in the conduit 68 is higher than the pressure in the conduit 66, the connectors 75a to 75d move in the decelerating direction, thereby reducing the output torque of the motors 76a to 76d by the capacity.

Advantageously, there is no direct coupling between the accelerator 70 and the engine 12. Rather, the operation and control of the engine 12 is based on engine speed (based on signal on line 42), torque (based on displacement control valve 60 position affected by accelerator position), and (based on signal on line 38a). This is based on a combination with system pressure. With this combination of inputs, the throttle control module 40 of the system 10 provides proportional control of the engine 12 and the system 10 based on known engine efficiency parameters, thus operating the engine 12 at its peak efficiency at all times. . When the system 10 is fully filled, the engine 12 is advantageously stopped to reduce instantaneous fuel consumption to zero. When the system pressure drops, the engine 12 restarts and again provides pressure to the conduit 20.
Based on the state or operating state of the air conditioner compressor 24, power management module 28, and accumulator 38 (as determined by the respective signals on lines 24a, 28a, 38a), throttle control module 40 goes to line 42. To start or stop the engine 12 and / or change the capacity of the pump / motor 16.

  As the system pressure in conduit 20 increases, accumulator 38 fills and the flow from pump / motor 16 decreases. Pump / motor 16 flow continues to decrease until system pressure decreases due to the output of motors 76a-76d. Whenever the flow of the pump / motor 16 reaches zero, the engine 12 stops until a flow is needed again. Also, if the accessory requires power and prevents the engine 12 from stopping (assuming the accessory is clutched to the engine 12), the pump / motor 16 flow is reduced. The powertrain system 10 obtains its efficiency by averaging the rate of power consumption. The energy required for the intermittent burst is supplied by the energy stored in the accumulator 38. The pump / motor 16 provides a large flow compared to the average flow required to propel the vehicle. Excess flow obtained by the pump 16 is stored in the accumulator 38.

The hydraulic hybrid powertrain system 10 according to the present invention advantageously provides an uncomplicated and straightforward control methodology, and the output torque response from the motors 76a-76d once their capacity increases, Thanks to the fact that it is very quick, it provides a very sensitive control means for the system 10.
One skilled in the art will recognize that the system 10 according to the present invention can be used to provide hydraulic output to any number of systems, including but not limited to ships, boats, or submarines. Includes propulsion systems for ascent or submersibles, helicopter propulsion systems, etc. In short, the output of the pump / motor 16 is used in conjunction with the powertrain system 10 to drive any number of hydraulic motors, such as motors 76a-76d, for any number of purposes, and these are within the scope of the present invention. It is.
The signals on connectors 73, 75a-75d, 80 and lines 24a, 28a, 38a, 42 are any type of mechanical connectors such as hydraulic lines, cables, metal rods, or communicate with solenoid valves. Electrical signals that fall within the scope of the present invention.

  In accordance with the provisions of the patent statute, the invention has been described in what is considered to represent its preferred embodiment. However, it should be noted that the invention can be practiced otherwise than as specifically illustrated and described without departing from the spirit or scope of the invention.

FIG. 1a is a schematic diagram illustrating a hydraulic hybrid powertrain system according to the present invention, with the mode selection valve in the “drive” position. FIG. 1 b shows the hydraulic hybrid powertrain system of FIG. 1 a with the mode selection valve in the “neutral” position. FIG. 1c shows the hydraulic hybrid powertrain system of FIG. 1a, with the mode selection valve in the “reverse” position. FIG. 1d shows the hydraulic hybrid powertrain system of FIG. 1a with the mode selection valve in the “parking” position. FIG. 1e shows the hydraulic hybrid powertrain system of FIG. 1a with the brake override device in the override position. FIG. 2 is an enlarged schematic view of the drive motor and the capacity control device of FIGS. 1a to 1d. FIG. 3 is an enlarged schematic view of the brake override device and the one-way bridge circuit of FIGS. 1a to 1d. FIG. 4 is an exploded perspective view showing an inner gear pump / motor according to the present invention. FIG. 5 is a partially exploded perspective view showing an outer gear pump / motor according to the present invention.

Claims (9)

A hydraulic hybrid powertrain system,
A power unit that generates high-pressure fluid at the output;
At least one drive motor for generating a rotational movement from the high-pressure fluid to the output;
Mode selection means connected to the power unit and the at least one drive motor for selecting an operation mode of the at least one drive motor;
Control means connected to the power unit and the at least one drive motor for controlling the operation of the at least one drive motor;
Selectively operating brake means for interrupting the flow of high pressure fluid to the at least one drive motor;
A one-valve bridge circuit that allows fluid flow through the at least one drive motor from a low pressure fluid source to an output of the power plant when the control means drives the brake means in response to a brake input;
Equipped with a,
The one-way bridge circuit (82)
A first one-way valve (84) having an outlet in fluid communication with the output of the power plant (20, 98) and an inlet;
A second one valve (86) having an outlet in fluid communication with the inlet of the first one valve and an inlet in fluid communication with the low pressure fluid source (18, 94);
A third one-way valve (88) having an inlet and an outlet in fluid communication with the low pressure fluid source;
An inlet in fluid communication with the outlet of the third one-way valve and a fourth one-valve (90) having an outlet in fluid communication with the output of the power plant.
A system characterized by that.   The system of claim 1, wherein the power plant includes an engine that drives a hydraulic pump / motor to generate the high pressure fluid.   The mode selection means includes a mode selection valve. In the drive mode and the reverse mode, the at least one drive motor is connected between the output of the power unit and a low-pressure fluid source, and in the neutral mode, the mode selection valve At least one drive motor is disengaged from the power unit output and connected to the low pressure fluid source, and in the parking mode, the at least one drive motor is disengaged from the power unit output and the low pressure fluid source. The system according to claim 1.   The mode selection means comprises brake override means, and typically connects the at least one drive motor between the power unit and the low pressure fluid source and is responsive to a brake input to respond to the at least one drive. 4. The system of claim 3, wherein a motor is disengaged from the power unit and the low pressure fluid source.   2. The system of claim 1, wherein the at least one drive motor is a variable displacement pump / motor, and the control means selectively changes the capacity of the pump / motor.   The control means comprises a capacity control valve and a hydraulic actuator connected to the output of the power plant and the low pressure fluid source, the hydraulic actuator being connected to the at least one drive motor for changing capacity. The system according to claim 5, wherein the system is connected.   The said capacity control valve has an acceleration position, a holding | maintenance position, and a deceleration position, respectively, The said at least 1 drive motor is accelerated, a speed is maintained, and it decelerates. system.   The system of claim 6, further comprising a feedback connector connected between the volume control valve and the hydraulic actuator.   The at least one drive motor is a variable displacement pump / motor, the control means selectively varies the capacity of the pump / motor, and the output of the drive motor is connected to rotate a vehicle wheel. The system according to claim 1, wherein:

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