DE102007012716B4 - Hybrid powertrain with a valve arrangement for two pumps - Google Patents

Abstract

Drive train (10) comprising:
a first pump (50) arranged to supply hydraulic pressure;
a first power source (18) operatively connected to the first pump (50) and configured to selectively drive the first pump (50);
a second pump (42) arranged to supply hydraulic pressure;
a second power source (14) operatively connected to the second pump (42) and configured to selectively drive the second pump (42);
a channel (120) forming a passage (116);
a gear (38) in fluid communication with the passage (116); and
a valve assembly (76);
wherein the valve assembly (76) is sufficiently configured to operate in a first mode of operation in which the valve assembly (76) provides fluid communication between the first pump (50) and the passage (116) and fluid communication between the second pump (42). and the passage (116) prevents a second mode in which ...

Description

TECHNICAL AREA

These This invention relates to valve assemblies adapted to to selectively apply hydraulic pressure from two pumps to a transmission to deliver.

BACKGROUND OF THE INVENTION

Hybrid powertrains usually use an internal combustion engine and an electric motor that works effectively with connected to a transmission. Under certain conditions will the internal combustion engine is switched off and restarted to the Improve fuel economy. When the internal combustion engine is switched off, it is desirable the gear engaged to let the delay time, to drive power to the wheels muster when commanded by the driver to reduce. Automatic transmissions require hydraulic Pressure to be applied to clutches to maintain the engagement to obtain. The hydraulic pressure is from an oil pump to disposal posed.

at Driven by the prior art, the oil pump from the internal combustion engine driven. When the combustion engine is switched off another Means are provided to supply the clutches with pressure. Some hybrid powertrains In the prior art, an auxiliary pump comprising the Electric motor is driven to couplings with hydraulic pressure in order to maintain the transmission engagement. A valve controls the hydraulic pressure, so he either exclusively from the driven by the internal combustion engine pump or exclusively by the auxiliary pump available is provided. Accordingly, the main pump must be sufficiently sized be enough Pressure available to put the clutch engagement maintained when the internal combustion engine operated at low speed becomes.

In the DE 23 29 328 A1 discloses an automatic Zuschaltventil for a hydraulic system. The hydraulic system is equipped with a main pump and a reserve pump. In the event of a failure of the delivery flow of the main pump, the connection valve ensures that the functionality of the hydraulic system is ensured by the reserve pump.

The DE 32 06 353 C2 discloses a valve assembly for a hydraulic system comprising a first and a second pump. Depending on the load on the system by a consumer, the valve assembly effects delivery of hydraulic fluid through the first pump alone or through both pumps simultaneously.

SUMMARY OF THE INVENTION

One Powertrain includes a first pump, a second pump, and a channel that forms a passage. A valve arrangement connects the first pump, the second pump and the passage are effective with each other. The valve assembly is for configured at least three operating modes. In a first mode ensures the valve assembly for a fluid connection between the first pump and the passage and lets no fluid communication between the second pump and the fluid passage to. In a second mode, the valve assembly provides fluid communication between both the first and second pumps and the fluid passage. In a third mode the valve assembly does not provide fluid communication between the first pump and the passage to and takes care of a fluid connection between the second pump and the passage.

The Valve arrangement allows It thus provides both pumps with pressurized fluid independently to provide the passage and also allows both pumps, to deliver pressurized fluid to the passage at the same time, allowing each pump to deliver the other pump to the passageway strengthened. This reinforcement allows, that at least one of the pumps is smaller than state-of-the-art pumps technology, which reduces the fuel consumption of the pumps becomes. The second mode of the valve also ensures a smooth transition between operation with only the first pump and operation with only the second pump, d. H. the second mode is reduced or minimized the influence on the pressure in the passage during the transition from the first mode to the third mode.

According to the invention the powertrain a first energy source such as a Electric motor and a second energy source such as a Internal combustion engine and a transmission. The first and the second energy source are in hybrid connection to the input shaft of the transmission to deliver a torque. The first energy source is effective with the first pump connected to selectively drive the first pump, and the second power source is operatively connected to the second pump, to selectively drive the second pump. The passage is in Fluid communication with the transmission, and in particular is the passage in fluid communication with the hydraulic clutch actuation circuit of the transmission.

The valve assembly comprises a valve body forming a chamber defined by a first Opening and a second opening, a first pendulum body which in the chamber between a first position in which the first pendulum body blocks the first opening, whereby a fluid connection between the passage and the first pump is prevented, and a second position selectively displaceable wherein the first pump is in fluid communication with the passage and a second shuttle located in the chamber between a first position where the second shuttle blocks the second port, thereby preventing fluid communication between the passage and the second pump , and a second position is selectively displaceable, in which the second pump is in fluid communication with the passage.

According to one exemplary embodiment the valve assembly is set up so that the first, second and third modes as a result of the hydraulic pressure exerted by the first and second pumps is automatically enter. Especially In the exemplary embodiment, the first mode occurs automatically when the hydraulic pressure from the first pump is higher than one is the first predetermined amount, the second mode automatically occurs when the hydraulic pressure from the second pump is higher than is a second predetermined amount, and enters the third mode automatically when the hydraulic pressure from the second pump is higher than a third predetermined amount.

Further a corresponding procedure is provided.

The mentioned features and advantages and other features and advantages The present invention is illustrated by the following detailed Description of the best mode for carrying out the invention in conjunction with the associated Drawings easily recognizable.

BRIEF DESCRIPTION OF THE DRAWINGS

1 is a schematic representation of a hybrid drive with a valve assembly, which is shown in a partially sectioned side view in a first mode of operation;

2 is a schematic, partially sectioned side view of the valve assembly of 1 in a second mode of operation;

3 is a schematic, partially sectioned side view of the valve assembly of 1 in a third mode of operation;

4 is a schematic, partially sectioned side view of the valve assembly of 1 in a fourth mode of operation;

5 is a schematic, partially sectioned side view of the valve assembly of 1 in a fifth mode of operation; and

6 is another schematic, partially sectioned side view of the valve assembly of 1 ,

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to 1 is a hybrid powertrain 10 shown schematically. The powertrain 10 comprises a first energy source and a second energy source in hybrid connection. In the illustrated embodiment, the first power source is an internal combustion engine 14 and the second power source is an electric motor 18 , The internal combustion engine 14 includes a rotatable crankshaft 22 and the electric motor 18 includes a rotor 26 , A selectively-engageable torque-transmitting device 30 such as a coupling connecting the rotor 26 and the crankshaft 22 together.

The rotor 26 is with the input shaft 34 a gearbox 38 coupled, as is natural for professionals. A selectively engageable torque transmitting device (not shown) or a hydraulic torque converter (not shown) may be disposed between the input shaft 34 and the rotor 26 be used. The crankshaft 22 is thus also with the input shaft 34 of the transmission 38 over the rotor 26 connected when the torque transmitting device 30 is indented. Accordingly, the rotor 26 and the crankshaft 22 effective with the input shaft 34 connected to provide them selectively with mechanical energy. Those skilled in the art will be aware of other hybrid powertrain arrangements that may be used in the claimed invention.

A skin pump 42 is effective with the crankshaft 22 connected, such as via a belt drive or a chain drive 46 to be powered by. An auxiliary pump 50 is effective with the rotor 26 connected, such as via a belt drive or a chain drive 54 to be powered by. A channel 60 makes a passage 64 which is in fluid communication with the main pump 42 stands; the main pump 42 is adapted to pressurized fluid, ie hydraulic pressure, to the passage 64 as will be understood by those skilled in the art. A channel 68 makes a passage 72 which is in fluid communication with the auxiliary pump 50 stands; the auxiliary pump 50 is set to pressurized fluid to the passage 72 to deliver, as for professionals selbstver is understandable.

The powertrain 10 further includes a valve assembly 76 which is in fluid communication with the passageways 64 . 72 stands. The valve arrangement 76 includes a valve body 80 which is a cylindrical chamber 84 forms. The valve arrangement 76 includes first and second pendulum bodies (shuttles) 88 . 92 which is inside the chamber 84 are positioned, and which for a selective displacement within the chamber 84 are formed. The chamber 84 is through two openings 96 . 100 which are at opposite ends of the chamber 84 from the valve body 80 be formed. The opening 96 is in fluid communication with the passage 72 of the canal 68 and thus is also in fluid communication with the auxiliary pump 50 , The opening 100 is in fluid communication with the passage 64 of the canal 60 and thus is also in fluid communication with the main pump 42 ,

The chamber 84 is also through two openings 104 . 108 marked the chamber 84 and another chamber 112 connect with each other. The openings 104 . 108 extend radially from the chamber 84 , The chamber 112 is in fluid communication with a passage 116 passing through a canal 120 is formed. The passage 116 is in fluid communication with a pressure regulating valve 124 , and the pressure control valve 124 is in fluid communication with the transmission 38 to supply pressurized fluid to the hydraulic circuit of the transmission, which includes clutch actuation chambers (not shown), as will be understood by those skilled in the art. The pressure control valve 124 is in particular a channel 128 which is a passage 132 forms, in fluid communication with the transmission 38 , The openings 104 . 108 thus stand with the passage 116 , the pressure control valve 124 and the transmission 38 in fluid communication. An exemplary hydraulic circuit for a transmission is in the U.S. Patent No. 5,601,506 described on February 11, 1997 to Long et al. and which is hereby incorporated by reference in its entirety.

The passage 72 is also in fluid communication with a pressure relief valve 136 , and the passage 64 is also in fluid communication with a pressure relief valve 140 as is natural to those skilled in the art. Each pressure relief valve includes a spring 144 which is a closure 148 biases. When the pressure in the passage 72 exceeds a predetermined amount, the pressure overcomes the bias of the spring 144 so that the shutter 148 the pressure relief valve 136 not blocked and then pressure is released as fluid passes through the pressure relief valve 136 is delivered. If, in a similar way, the pressure in the passage 64 exceeds a predetermined amount, the pressure overcomes the bias of the spring 144 so the closure 148 the pressure relief valve 140 not blocked and then pressure is released as fluid passes through the pressure relief valve 140 is delivered. The pressure at which the pressure relief valve 140 opens, is greater than the pressure at which the pressure relief valve 136 opens.

The pendulum body 88 is by a substantially cylindrical surface 152 characterized, which sealing the inner surface of the chamber 84 touched. The pendulum body 88 is also through a surface 156 characterized in fluid communication with the passage 72 of the canal 68 stands. The pendulum body 88 is also through a surface 160 marked leading to the chamber 84 exposed.

Similarly, the pendulum is 92 by a substantially cylindrical surface 164 characterized, which sealing the inner surface of the chamber 84 touched. The pendulum body 92 is also through a surface 168 which is in fluid communication with the passage 64 of the canal 60 stands. The pendulum body 92 is also through a surface 170 marked, which to the chamber 84 exposed and the surface 160 opposite. The pendulum body 92 also forms a chamber 174 which over the opening 108 and a feedback port 178 which are radial with respect to the pendulum body 92 extends in fluid communication with the chamber 112 stands. The chamber 174 is in the direction of the pendulum body 88 opened to the chamber 84 and the surface 160 of the pendulum body 88 to be in fluid communication. The pendulum body 92 forms in the surface 164 a concavity 182 to make sure the fluid connection between the feedback port 178 and the chamber 112 during the movement of the pendulum body 92 is not blocked.

A coil spring 186 is inside the chamber between the pendulum bodies 88 . 92 interposed and tensioned the pendulum body 88 . 92 against each other as it is in 1 is shown. The pendulum body 88 is by a supernatant 190 from the surface 156 characterized; the supernatant 190 touches a wall of the canal 68 to the movement of the pendulum body 88 to limit. Similarly, a part stands 194 from the surface 168 of the pendulum body 92 and touches a wall of the canal 60 to the movement of the pendulum body 92 to limit.

A first mode of operation of the valve assembly is in 1 shown. In particular, the internal combustion engine 14 and the engine 18 stopped or shut down, put the pumps 42 . 50 the fluid in the passages 64 . 72 not under pressure, which makes it possible for the spring 168 the pendulum body 88 . 92 , as shown, in respective biased closed positions. The pendulum body 88 blocks the openings 96 and 104 to establish a fluid connection between the passage 72 and thus the auxiliary pump 50 and the chamber 112 to prevent. The pendulum body 92 blocks the opening 100 , whereby a fluid connection between the passage 64 and thus the main pump 42 and the chamber 112 is prevented.

With reference to 2 in which like reference numerals refer to like components as in FIG 1 refer, is the valve assembly 76 shown in a second mode of operation. In particular, the engine is driving (in 1 With 18 designated) the auxiliary pump (in 1 With 50 ), causing the auxiliary pump to pressurize fluid 200A in the passage 72 of the canal 68 to deliver. The pressurized fluid 200A exerts a force on the surface 156 of the pendulum body 88 out. The force on the surface 156 overcomes the bias of the spring 186 and causes the pendulum body 88 in the direction of the pendulum body 92 and to move it to an open position, as shown, in which the pendulum body 88 the openings 96 and 104 not completely blocked. If, accordingly, the pendulum body 88 In its open position, there is a fluid connection between the chamber 112 and the passage 72 over the opening 96 , a part of the chamber 84 and the opening 104 allows. Pressurized fluid 200A thus flows from the auxiliary pump into the chamber 112 , the passage 116 and finally into the clutch actuation chambers of the transmission (in 1 With 38 designated). The second mode of operation thus occurs automatically when the pressure in the passage 68 is sufficient to the movement of the pendulum body 88 to effect its open position.

When the valve assembly is in its second mode of operation, the force of the fluid pushes 200A on the pendulum body 88 the feather 186 together and generates a corresponding increase in force on the pendulum body 92 ; the part 194 but hinders the pendulum body 92 at it, out of the chamber 84 out about his completely closed, in the 1 and 2 herauszuahren position shown in the pendulum body 92 a flow path between the openings 100 and 108 blocked, creating a fluid connection between the passage 64 and the chamber 112 is prevented. During the first operating mode, the internal combustion engine (with 14 not designated) and consequently the main pump (in 1 With 42 no pressurized fluid to the passage 64 ,

With reference to 3 in which the same reference numbers refer to the same components 1 and 2 refer, is the valve assembly 76 shown in a third mode of operation. In particular, the internal combustion engine (in 1 With 14 designated) in operation and drives the main pump (in 1 With 42 designated) on; accordingly, the main pump supplies pressurized fluid 200B to the passage 64 of the canal 60 ,

The pressurized fluid 200B exerts a force on the surface 168 of the pendulum body 92 out. The power on the surface 168 overcomes the bias of the spring 186 and causes the pendulum body 92 , in the direction of the pendulum body 88 and, as shown, to move to an open position in which the pendulum body 92 the openings 100 and 108 not completely blocked. Accordingly, when the shuttle is in its open position, the chamber is stationary 112 over the opening 100 , a part of the chamber 84 and the opening 108 in fluid communication with the passage 64 , Pressurized fluid 200B thus flows from the main pump into the chamber 112 , the passage 116 and finally into the clutch actuation chambers of the transmission (in 1 With 38 designated).

The auxiliary pump also supplies pressurized fluid during the second mode of operation 200A , and thus keeps the pressurized fluid 200A the pendulum body 88 in the open position, thereby allowing pressurized fluid 200A from the auxiliary pump into the chamber 112 flows. Accordingly, the third operating mode automatically occurs when the pressure in passage 64 is sufficient to the pendulum body 92 to move to its open position.

With reference to 4 in which the same reference numbers refer to the same components 1 - 3 Referring to FIG. 1, the valve assembly is shown in a fourth mode of operation. The fourth mode of operation is automatically effected when the fluid 200B , which is pressurized by the main pump, a higher pressure than the fluid 200A on, which is pressurized by the auxiliary pump. In particular, the fluid exerts 200B from the main pump, a force on the pendulum body 92 including the surface 168 from what a movement of the pendulum body 92 with a corresponding compression of the spring 186 causing, in turn, a force on the pendulum body 88 exerts, causing the pendulum body 88 is forced into its closed position. In addition, the opening causes 178 the pressure in the chamber 174 and, correspondingly, the pressure in the chamber 84 and on the surface 160 to, on the pressure in the passage 64 to increase. The power of the spring 186 and from that to the surface 160 acting fluid is greater than the force acting on the surface 156 of the pendulum body 88 through the fluid 200A is exerted by the auxiliary pump, which is a lower pressure than the fluid 200B from the main pump having. Accordingly, the pendulum body moves away 88 from the pendulum body 92 in the position shown in the pendulum body 88 the opening 104 blocked, creating a fluid connection between the auxiliary pump and the chamber 112 is prevented.

With reference to 5 in which the same reference numbers refer to the same components 1 - 4 refer, is the valve assembly 76 shown in a fifth mode of operation in which the pressure of the fluid 200B sufficiently larger than the pressure of the fluid 200A is, so that the force by the spring 186 and by the fluid from the opening 178 on the pendulum body 88 including the surface 160 is exercised sufficiently greater than the force exerted by the fluid 200A on the surface 156 is exercised, causing the pendulum body 88 is caused to move to its fully closed position in which the pendulum body 88 both openings 196 and 104 blocked. Since the auxiliary pump is isolated (deadheaded), ie fluid flow from the auxiliary pump is blocked, the pressure of the fluid 200A in the passage 72 be high enough so that the fluid 200A will be discharged through the auxiliary relief valve, as in 5 shown.

With reference to 6 in which like reference numerals refer to like components as in FIG 5 The auxiliary pump is shut down because the crankshaft of the internal combustion engine has reached a sufficiently high speed to drive the main pump to flow in the fluid 200B to generate enough pressure so that a gain from the auxiliary pump is not needed.

While the best form for execution the invention has been described in detail, those with are familiar with the prior art, to which this invention relates, various alternative designs and embodiments for execution recognize the invention within the scope of the appended claims.

Claims (10)

Powertrain ( 10 ) comprising: a first pump ( 50 ) arranged to provide hydraulic pressure; a first energy source ( 18 ) which is effective with the first pump ( 50 ) and set up the first pump ( 50 ) to drive selectively; a second pump ( 42 ) arranged to provide hydraulic pressure; a second energy source ( 14 ) which works effectively with the second pump ( 42 ) and is set up to the second pump ( 42 ) to drive selectively; a channel ( 120 ), which one passage ( 116 ) forms; a gearbox ( 38 ), with the passage ( 116 ) is in fluid communication; and a valve assembly ( 76 ); the valve arrangement ( 76 ) is sufficiently adapted to operate in a first operating mode in which the valve arrangement ( 76 ) for fluid communication between the first pump ( 50 ) and the passage ( 116 ) and fluid communication between the second pump ( 42 ) and the passage ( 116 ) prevents a second mode in which the valve assembly ( 76 ) for fluid communication between both the first and second pumps ( 50 . 42 ) and the passage ( 116 ) and to operate a third mode in which the valve assembly ( 76 ) a fluid connection between the first pump ( 50 ) and the passage ( 116 ) and prevents fluid communication between the second pump ( 42 ) and the passage ( 116 ); the valve arrangement ( 76 ) comprises: a valve body ( 80 ), which has a chamber ( 84 ) formed by a first opening ( 96 ) and a second opening ( 100 ) is marked; a first pendulum body ( 88 ), which in the chamber ( 84 ) between a first position in which the first pendulum body ( 88 ) the first opening ( 96 ), whereby a fluid connection between the passage ( 116 ) and the first pump ( 50 ) and a second position is selectively displaceable, in which the first pump ( 50 ) in fluid communication with the passageway ( 116 ) stands; and a second pendulum body ( 92 ) in the chamber ( 84 ) between a first position in which the second pendulum body ( 92 ) the second opening ( 100 ), whereby a fluid connection between the passage ( 116 ) and the second pump ( 42 ) is selectively displaceable, and a second position is selectively displaceable, in which the second pump ( 42 ) in fluid communication with the passageway ( 116 ) stands. Powertrain ( 10 ) according to claim 1, wherein the valve arrangement ( 76 ) is set up such that the first mode automatically occurs when the first pump ( 50 ) delivers a hydraulic pressure that exceeds a first predetermined amount, and the second mode automatically occurs when the second pump ( 42 ) provides a hydraulic pressure exceeding a second predetermined amount. Powertrain ( 10 ) according to claim 1, wherein the valve arrangement ( 76 ) one between the first and second pendulum body ( 88 . 92 ) arranged spring ( 186 ), so that the spring ( 186 ) the first and second pendulum bodies ( 88 . 92 ) in their respective first positions. Powertrain ( 10 ) according to claim 3, wherein the first pendulum body ( 88 ) one with the first pump ( 50 ) in fluid communication with the first surface ( 156 ), the first surface ( 156 ) is sufficiently positioned so that a sufficient the hydraulic pressure on the first surface ( 156 ) causes the first pendulum body to move from its first position to its second position; and wherein the second pendulum body ( 92 ) one with the second pump ( 42 ) in fluid communication second surface ( 168 ), the second surface ( 168 ) is sufficiently positioned so that a sufficient hydraulic pressure on the second surface ( 168 ) the second pendulum body ( 92 ) to move from his first position to his second position. Powertrain ( 10 ) according to claim 4, wherein the second pendulum body ( 92 ) an opening ( 178 ), which is responsible for a fluid connection between the passage ( 116 ) and the chamber ( 84 ). Valve arrangement ( 76 ) comprising: a valve body ( 80 ), which has a chamber ( 84 ) formed by first, second, third and fourth openings ( 96 . 100 . 104 . 108 ) is marked; a first pendulum body ( 88 ), which between a first position in which the first pendulum body ( 88 ) a fluid connection between the first and third openings ( 96 . 104 ) and a second position is selectively movable, in which the first and third opening ( 96 . 104 ) are in fluid communication with each other; a second pendulum body ( 92 ) between a first position in which the second pendulum body ( 92 ) fluid communication between the second and fourth openings ( 100 . 108 ) and a second position is selectively movable, in which the second and fourth opening ( 100 . 108 ) are in fluid communication with each other; the second pendulum body ( 92 ) an opening ( 178 ), through which the fourth opening ( 108 ) and the first pendulum body ( 88 ) are in fluid communication with each other. Valve arrangement ( 76 ) according to claim 6, wherein the valve body ( 80 ) comprises a surface which at least partially surrounds the chamber ( 84 ) and wherein the first and second pendulum bodies ( 88 . 92 ) touch the surface sealingly. Valve arrangement ( 76 ) according to claim 6, further comprising a spring ( 186 ) within the chamber ( 84 ) between the first and second pendulum bodies ( 88 . 92 ), so that the spring ( 186 ) the first and second pendulum bodies ( 88 . 92 ) in their respective first positions. Valve arrangement ( 76 ) according to claim 6, wherein the first pendulum body ( 88 ) is sufficiently set up and positioned so that a sufficient pressure at the first opening ( 96 ) the first pendulum body ( 88 ) to move to its associated second position; and wherein the second pendulum body ( 92 ) is sufficiently set up and positioned so that a sufficient pressure at the second opening ( 100 ) causes the second pendulum body to move to its associated second position. Method for providing hydraulic pressure to a transmission ( 38 ) in a hybrid powertrain ( 10 ), one of a first energy source ( 18 ) driven first pump ( 50 ) and one from a second energy source ( 14 ) driven second pump ( 42 ), the method comprising: the drive train ( 10 ) is operated in a first mode in which a fluid connection between the first pump ( 50 ) and the transmission ( 38 ) while providing fluid communication between the second pump ( 42 ) and the transmission ( 38 ) is prevented; after operating the powertrain ( 10 ) in a first mode the powertrain ( 10 ) is operated in a second mode in which at the same time a fluid connection between the first pump ( 50 ) and the transmission ( 38 ) and a fluid connection between the second pump ( 42 ) and the transmission ( 38 ) provided; and after operating the powertrain ( 10 ) in a second mode the transmission ( 38 ) is operated in a third mode in which a fluid connection between the first pump ( 50 ) and the transmission ( 38 ) is prevented while a fluid connection between the second pump ( 42 ) and the transmission ( 38 ) provided.