JP2008039007A - Transmission for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission which is excellent in transmission efficiency of power, easily reduced in size/weight, and can continuously change speed. <P>SOLUTION: In the transmission for a vehicle, first and second drive shafts 4, 11, and a third drive shaft 12 and a first driven shaft 13 are disposed on the mutually parallel axis. A first differential mechanism 5 is disposed coaxially with each of the drive shaft 4, 11. A first motor 6 is connected to a repulsion element of a first differential mechanism 5. A second first mechanism 7 is disposed coaxially with a third drive shaft 12. A second motor 8 is connected to the repulsion element of the second differential mechanism 7. A transmission mechanism 22 for starting is disposed on the axis parallel to the third drive shaft 12 to amplify and transmit a torque of the third drive shaft 12 to the second driven shaft 23. A switching mechanism 21 for starting selectively connects the first driven shaft 13 and the second driven shaft 23. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a transmission for a vehicle that includes a plurality of transmission mechanisms such as gear pairs in a power transmission system and is configured to change gears by switching between transmission mechanisms involved in torque transmission, and in particular, a machine such as a gear mechanism. The present invention relates to a transmission capable of using both power transmission by an automatic means and power transmission via pressure fluid such as hydraulic pressure or other energy forms such as electric power.

  An example of this type of transmission is described in Patent Document 1. The transmission described in Patent Document 1 is generated by a mechanical transmission (MT) that switches a torque transmission path in a planetary gear mechanism in accordance with an engagement / release state of a plurality of clutch mechanisms, and a hydraulic pump. A hydrostatic transmission (HST) that supplies pressure oil to a hydraulic motor to transmit power and shifts according to the supply state of the pressure oil is arranged in parallel between the input member and the output member. It is configured. In the transmission described in Patent Document 1, a gear ratio that changes stepwise is set by a mechanical transmission, whereas a gear ratio that is set by a hydrostatic transmission changes continuously. Therefore, the overall gear ratio can be changed continuously, and therefore, it can function as a so-called continuously variable transmission.

  Another example is described in Patent Document 2. The transmission described in Patent Document 2 distributes power output from a power source to a multi-stage transmission mainly including a plurality of gear pairs and a plurality of clutch mechanisms, and an HST (hydrostatic transmission). The power transmitted and shifted by the multi-stage transmission and the HST is synthesized by the planetary gear mechanism and then output. Therefore, in the transmission described in Patent Document 2, the overall gear ratio can be continuously changed by changing the ratio of the power transmitted by each of the multi-stage transmission and the HST by HST.

JP 11-51150 A JP 2000-320644 A

  As described above, in the transmission described in Patent Document 1, power is transmitted via a hydrostatic transmission, and the transmission ratio can be changed steplessly by changing the transmission ratio. However, in this case, power is transmitted through the fluid by directly driving the pump with the power of the power source, sending the generated fluid pressure to the motor and driving it, and outputting the power output by the motor as it is. To communicate to the side. Therefore, there is a possibility that the power transmission efficiency as a whole may not be sufficiently high due to a relatively large power loss, such as an increase in fluid pressure according to the torque to be transmitted.

  Such a situation is the same in the transmission described in Patent Document 2, and the configuration described in Patent Document 2 substantially includes the multi-stage transmission and the HST between the input member and the output member. Since the configuration is arranged in parallel, there is a possibility that the power transmission efficiency as a whole may not be sufficiently high, such as power loss increases when power transmission via HST is performed.

  Further, in any of the transmissions described in Patent Documents 1 and 2, a multi-plate clutch is used as a mechanism for inputting power output from a power source such as an engine to the transmission and shutting off the power. Therefore, power such as hydraulic pressure is consumed to maintain the input, and this may cause an increase in overall power loss or deterioration in power transmission efficiency.

  The present invention has been made paying attention to the above technical problem, and an object of the present invention is to provide a vehicle transmission capable of improving power transmission efficiency and vehicle fuel efficiency.

  In order to achieve the above object, the invention of claim 1 is directed to first to third drive shafts to which power is selectively transmitted from a power source, and first driven to which power is transmitted from each of the drive shafts. Shaft, a plurality of transmission mechanisms arranged between the drive shafts and the first driven shaft, and transmission of power between the drive shafts and the first driven shaft via the transmission mechanisms And a switching mechanism that selectively enables the first drive shaft and the second drive shaft to be concentrically arranged with each other so as to be rotatable relative to each other. A first drive shaft, a second drive shaft, and the first driven shaft are arranged on mutually parallel axes, and are connected to a first input element to which power is input from the power source and the first drive shaft. Output element and first counter A first differential mechanism having an element disposed on the same axis as the first drive shaft and the second drive shaft, and capable of recovering energy and outputting driving force, and recovering capacity and output capacity thereof A first motor variable in power is connected to the first reaction force element, a second input element to which power is input from the power source, a second output element connected to the second drive shaft, and a second reaction force element Is disposed on an axis parallel to the first drive shaft and the second drive shaft and in parallel with the first differential mechanism, and recovers energy and outputs driving force. And a second motor having a variable recovery capacity and variable output capacity is connected to the second reaction force element and arranged on an axis parallel to the third drive shaft connected to the second reaction force element. And the third drive shaft A starting transmission mechanism that amplifies torque and transmits the amplified torque to a second driven shaft and a starting switching mechanism that selectively connects the second driven shaft to the first driven shaft are provided. This is a vehicle transmission.

  The invention according to claim 2 is the invention according to claim 1, wherein the transmission mechanism includes a plurality of mechanisms capable of setting a plurality of gear ratios for the vehicle to travel, and the starting switching mechanism is When there is a request to increase the driving torque when starting, the second drive shaft and the first driven shaft are set in a state where torque can be transmitted between the second driven shaft and the first driven shaft. Between the second driven shaft and the first driven shaft when there is no request for increase in the drive torque, and Torque is transmitted between the second drive shaft and the first driven shaft via any one of the transmission mechanisms, or the first driven shaft and the second driven shaft are torqued with any other shaft. Cannot communicate It is a vehicle for transmission, characterized in that is configured to a state.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the starting transmission mechanism is configured such that the rotational speed of the third drive shaft is higher than the rotational speed of the second driven shaft. A transmission for a vehicle including a speed reduction mechanism having a gear ratio.

  According to a fourth aspect of the present invention, there is provided the invention according to any one of the first to third aspects, wherein the second differential mechanism includes a sun gear, a ring gear disposed concentrically with the sun gear, and the sun gear and the ring gear. And a single pinion type planetary gear mechanism having a carrier holding a pinion gear meshing with each other, the ring gear forming the second input element to which power is input from the power source, and the carrier is the first The vehicle transmission is characterized in that the second output element connected to the two drive shafts is formed, and the sun gear forms the second reaction force element connected to the second motor.

  According to a fifth aspect of the present invention, in the first aspect, the first motor is disposed on the same axis as the first differential mechanism, the first drive shaft, and the second drive shaft. The second motor is disposed on the same axis as the second differential mechanism and the third drive shaft and adjacent to the first motor in the radial direction on the outer side. This is a vehicle transmission.

  According to a sixth aspect of the present invention, in any of the first to fifth aspects of the present invention, each of the motors includes a variable displacement fluid pressure pump motor capable of changing an extrusion volume, and these variable displacement fluid pressure pump motors. The vehicle transmission is further provided with a fluid circuit that causes the two to communicate with each other.

  The invention according to claim 7 is the invention according to claim 6, wherein any one of the variable displacement fluid pressure pump motors includes a double-pump pump motor capable of changing the extrusion volume to both positive and negative. This is a vehicle transmission.

  The invention of claim 8 is the invention according to any one of claims 1 to 5, wherein each of the motors includes a motor generator having a function as a generator and a function as an electric motor. This is a vehicle transmission.

  Therefore, according to the first aspect of the present invention, since the power output from the power source is input to the input element of each differential mechanism, according to the reaction force from each motor with respect to each reaction force element, Power is output from the output element. For example, if one of the motors outputs torque so that the reaction force element in one of the differential mechanisms is fixed, and the other motor rotates idly, the power output from the power source is fixed by the reaction force element. It is transmitted to one of the drive shafts through the one differential mechanism. Then, when a predetermined transmission mechanism between the drive shaft and the first driven shaft is brought into a state where torque can be transmitted by any of the switching mechanisms, power is transmitted to the first driven shaft via the transmission mechanism. Communicated. As a result, a transmission gear ratio is set according to the rotation speed ratio of the transmission mechanism. In contrast, when a reaction force is applied to the reaction force element in one of the differential mechanisms while any of the motors rotates, a part of the power output from the power source is recovered by the motor. Since the energy is supplied to another motor and the other motor outputs power, the power is transmitted to the other drive shaft via the other differential mechanism to which the other motor is connected. That is, mechanical power transmission and power transmission accompanied by energy conversion occur, and power is transmitted to the first driven shaft via the two drive shafts and the transmission mechanism. In that case, the transmission ratio of power in each power transmission system is continuously changed by the differential action of each differential mechanism, so that the transmission ratio as a whole of the transmission is continuously changed, and the continuously variable transmission. Is possible.

  According to the second aspect of the present invention, when a large driving force is required when the vehicle starts moving forward or backward, the starting switching mechanism is provided between the second driven shaft and the first driven shaft. Torque transmission is enabled, and the output torque of the second motor is transmitted to the second driven shaft via the third drive shaft and the starting transmission mechanism, so that the output torque of the second motor is amplified and the first torque is transmitted. Directly transmitted to the driven shaft, the driving force at the start can be increased. When the vehicle starts and no large driving force is required, the starting switching mechanism is in a state where torque cannot be transmitted between the second driven shaft and the first driven shaft, or the second driven shaft. Can be in a neutral state in which torque cannot be transmitted to any other shaft, so that the second motor is used without being restricted by the rotational state of the first driven shaft, particularly during high-speed travel after starting. be able to.

  According to the invention of claim 3, the rotational speed of the second driven shaft is decelerated relative to the rotational speed of the third drive shaft, that is, the torque of the third drive shaft is amplified and transmitted to the second driven shaft. Is done. Therefore, by amplifying the output torque of the second motor input to the third drive shaft by making the starting switching mechanism in a state where torque can be transmitted between the second driven shaft and the first driven shaft, It can be transmitted directly to the first driven shaft.

  According to the fourth aspect of the present invention, the torque output from the second motor can be amplified and transmitted to the reaction force element in the second differential mechanism. The transmitted torque, that is, the driving torque at the start can be increased.

  Further, according to the invention of claim 5, since the first and second motors can be arranged adjacent to each other, the configuration for transferring energy between the motors is simplified. It is possible to improve the manufacturability and assembly of the transmission by unitizing the motor.

  According to the sixth and seventh aspects of the present invention, the torque transmitted to the first driven shaft can be controlled by generating a reaction force against each differential mechanism by the fluid pressure pump motor, so that the power loss can be reduced. In addition, the continuously variable transmission can be easily performed.

  According to the eighth aspect of the invention, since the shift control can be performed electrically, the control becomes easy.

  Next, a vehicle transmission according to the present invention will be described based on a specific example. The example shown in FIG. 1 is an example in which four forward speeds and one reverse speed are set as so-called fixed gear ratios that can be set without changing the form of power (energy) to be transmitted. This is an example configured to be suitable for an FR vehicle (front engine / rear drive vehicle) in which the power source 1 is mounted in the front-rear direction of the vehicle. That is, a mechanism for distributing, transmitting, and interrupting power is disposed on the same axis as the input member 2 connected to the power source 1 or on an axis parallel to the input member 2. Here, the power source 1 may be a general power source used in a vehicle such as an internal combustion engine, an electric motor, or a combination thereof. In the following description, the power source 1 is referred to as the engine 1 temporarily. Moreover, the input member 2 should just be a member which can transmit the motive power which the engine (E / G) 1 output, and may be a drive plate or an input shaft. In the following description, the input member 2 is referred to as an input shaft 2. Appropriate transmission means such as a damper, a clutch, and a torque converter can be interposed between the engine 1 and the input shaft 2. Reference numeral 3 denotes an oil pump called a sub pump or a charge pump, which supplies lubricating oil to each part in the transmission and pressure oil to an oil passage formed between each hydraulic pump motor described later. It is used for replenishment.

  The mechanism arranged on each axis outputs the input power as it is, or outputs a part of it as it is, and outputs other power by converting the energy form, and further idles. It is a kind of transmission means configured not to transmit power. In the example shown in FIG. 1, it is comprised by the differential mechanism and the reaction force mechanism which gives reaction force to this and the reaction force is variable. The differential mechanism may be any mechanism that performs a differential action by three rotating elements, and is a mechanism that uses gears and rollers as rotating elements. Among them, a single-pinion type planetary gear is used as the gear-type differential mechanism. A mechanism or a double pinion type planetary gear mechanism can be used. The reaction force mechanism may be a mechanism that can selectively output torque, and a hydraulic pump motor such as a hydraulic pressure or a motor / generator that operates electrically may be used.

  In the example shown in FIG. 1, a single pinion type planetary gear mechanism is used as a differential mechanism, and a variable displacement hydraulic pump motor is used as a reaction force mechanism (corresponding to the motor of the present invention) for generating a reaction force. It has been. In the following description, a planetary gear mechanism disposed on the same axis as the first drive shaft 4 parallel to the engine 1 and the input shaft 2 is temporarily referred to as a first planetary gear mechanism 5, and a hydraulic pump motor is temporarily referred to as a first pump. This will be referred to as motor 6. Further, the planetary gear mechanism arranged in parallel with this will be referred to as a second planetary gear mechanism 7, and the hydraulic pump motor will be referred to as a second pump motor 8. In addition, the 1st pump motor 6 may be described as PM1 in a figure, and the 2nd pump motor 8 may be described as PM2 in a figure.

  The first planetary gear mechanism 5 rotates and rotates a sun gear S1 that is an external gear, a ring gear R1 that is an internal gear disposed concentrically with the sun gear S1, and a pinion gear that meshes with the sun gear S1 and the ring gear R1. This is a single-pinion type planetary gear mechanism that rotates a carrier C1 that is revolving freely. A counter drive gear 9A of the first counter gear pair 9 is attached to the input shaft 2, and one counter driven gear 9B meshing with the counter drive gear 9A is connected to the ring gear R1. That is, the input shaft 2 is connected to the ring gear R1 via the first counter gear pair 9. Therefore, the ring gear R1 is an input element. Further, the rotor shaft 6A of the first pump motor 6 as a reaction force mechanism is connected to the sun gear S1. Therefore, the sun gear S1 is a reaction force element. The first drive shaft 4 is connected to the carrier C1. Therefore, the carrier C1 is an output element.

  The first pump motor 6 is a variable displacement type that can change the extrusion volume. In the example shown in FIG. 1, the first pump motor 6 is a so-called single swing type that can change the extrusion volume from zero to either positive or negative. The first planetary gear mechanism 5 is disposed on the same axis as the first planetary gear mechanism 5 on the engine 1 side (left side in FIG. 1). As this type of first pump motor 6, various types of pumps can be employed. For example, a swash plate pump, a swash shaft pump, or a radial piston pump can be used.

  On the other hand, the second planetary gear mechanism 7 has the same configuration as that of the first planetary gear mechanism 5 described above, and the carrier C2 holds the sun gear S2, the ring gear R2, and the pinion gear meshing with the sun gear S2 and the pinion gear so as to rotate and revolve. Is a single pinion type planetary gear mechanism that performs differential action by these three rotating elements. Similarly to the first planetary gear mechanism 5 described above, the other counter driven gear 9C meshed with the counter drive gear 9A attached to the input shaft 2 is connected to the ring gear R2. That is, the input shaft 2 is connected to the ring gear R <b> 2 via the first counter gear pair 9. Therefore, the ring gear R2 is an input element. In addition, the rotor shaft 8A of the second pump motor 8 as a reaction force mechanism is connected to the sun gear S2. Therefore, the sun gear S2 is a reaction force element. A counter drive gear 10 </ b> A of the second counter gear pair 10 is attached to the carrier C <b> 2, and a counter driven gear 10 </ b> C meshed with the carrier drive C <b> 10 via an idle gear 10 </ b> B is connected to the second drive shaft 11. That is, the second drive shaft 11 is connected to the carrier C <b> 2 via the second counter gear pair 10. Therefore, the carrier C2 is an output element.

  The sun gear S2 is connected to the second pump motor 8 and to a third drive shaft 12 connected to a starting transmission mechanism described later. That is, the third drive shaft 12 is connected to the second pump motor 8 on the opposite side in the axial direction across the sun gear S2. The third drive shaft 12 has a shorter overall length than the first drive shaft 4 or the first driven shaft 13 described later, and is a part of the entire transmission, specifically, the engine 1 of the transmission. It is arranged in a part of the side. Also, the first counter gear pair 9 and the second counter gear pair 10 constitute a so-called input transmission mechanism and output transmission mechanism, respectively, which are a transmission mechanism using a friction wheel, a chain or It is also possible to replace with a winding transmission mechanism using a belt or the like.

  The second pump motor 8 is a variable displacement type that can change the extrusion volume. In the example shown in FIG. 1, the second pump motor 8 is of a so-called double swing type that can change the extrusion volume from zero to both positive and negative directions. The second planetary gear mechanism 7 and the third drive shaft 12 are disposed on the same axis and adjacent to the outside in the radial direction of the first pump motor 6 described above. As this type of second pump motor 6, various types of pumps can be adopted as in the case of the first pump motor 6. For example, a swash plate pump, a swash shaft pump, or a radial piston pump can be used. it can.

  Further, in the configuration example shown in FIG. 1, the first planetary gear mechanism 5 and the second planetary gear mechanism 7 are arranged in parallel with each other in parallel in the axial direction. That is, with respect to the first planetary gear mechanism 5 disposed on the same axis as the first drive shaft 4, the second planetary gear mechanism 7 is arranged on an axis parallel to the first drive shaft 4 (that is, the third drive gear 4). On the same axis as the shaft 12) and adjacent to the outside in the radial direction of the first planetary gear mechanism 5. Therefore, as compared with the case where the two planetary gear mechanisms are shifted from each other in the axial direction, the length in the axial direction can be shortened to reduce the size of the transmission. Accordingly, the onboard performance of the transmission can be improved, and in particular, the onboard performance when mounted on an FR vehicle can be improved.

  The first drive shaft 4 and the second drive shaft 11 are both disposed on the same axis as the first planetary gear mechanism 5 and the first pump motor 6. That is, two drive shafts of the first drive shaft 4 and the second drive shaft 11 are arranged on the axes of the first planetary gear mechanism 5 and the first pump motor 6. Among these, the second drive shaft 11 has a hollow structure and is fitted to the outer peripheral side of the first drive shaft 4 so as to be rotatable relative to each other. The drive shafts 4 and 11 are disposed on the opposite side in the axial direction from the first pump motor 6 with the first planetary gear mechanism 5 interposed therebetween.

  A first driven shaft 13 to which power is transmitted from each drive shaft 4, 11 is disposed so as to be parallel to each drive shaft 4, 11 and on the same axis as the input shaft 2. Therefore, the main portion of the transmission shown in FIG. 1 has a so-called biaxial structure (only a part where the third drive shaft 12 is disposed has a triaxial structure). A plurality of transmission mechanisms for setting different transmission gear ratios are provided between the drive shafts 4 and 11 and the first driven shaft 13. Each of these transmission mechanisms is for setting a gear ratio between the input shaft 2 and the first driven shaft 13 in accordance with the respective rotation speed ratio when involved in torque transmission. It is also possible to adopt a mechanism using a winding mechanism or a friction wheel. In the example shown in FIG. 1, four gear pairs 14, 15, 16, 17 for forward travel and a gear pair 18 for reverse travel are provided.

  The first drive shaft 4 protrudes from the end of the hollow second drive shaft 11, and a first speed drive gear 14A, a third speed drive gear 16A, and a reverse drive gear 18A are provided in the protruded portion. It is attached. The arrangement order is the order of the first speed drive gear 14A, the third speed drive gear 16A, and the reverse drive gear 18A from the tip (right end in FIG. 1) side of the first drive shaft 4. In this way, the two gears of the first speed driving gear 14A and the third speed driving gear 16A for forward traveling are arranged in order of increasing gear ratio (in order of decreasing pit circle radius or decreasing number of teeth). By doing so, the load applied to the bearing (not shown) that supports the tip of the first drive shaft 4 can be made relatively low, and the bearing can be downsized.

  The second drive shaft 11 is attached with a fourth speed drive gear 17A, a second speed drive gear 15A, and the aforementioned counter driven gear 10C in this order from the tip side (the right side in FIG. 1). Therefore, an odd-numbered drive gear is attached to one of the first and second drive shafts 4 and 11, and an even-numbered drive gear is attached to the other. In other words, the second drive shaft 4 may be attached to the first drive shaft 4 and the first drive gear 11 may be attached to the second drive shaft 11.

  The driven gears 14B, 15B, 16B, 17B, 18B in each of the gear pairs 14, 15, 16, 17, 18 are supported by being rotatably fitted to the first driven shaft 13. That is, the first speed driven gear 14B is rotatably fitted to the first driven shaft 13 while meshed with the first speed drive gear 14A. The third speed driven gear 16B is rotatably fitted to the first driven shaft 13 while being engaged with the third speed drive gear 16A, and is disposed adjacent to the first speed driven gear 14B. Further, the second speed driven gear 15B is rotatably fitted to the first driven shaft 13 while being engaged with the second speed drive gear 15A, and is disposed adjacent to the fourth speed driven gear 17B. The fourth speed driven gear 17B is rotatably fitted to the first driven shaft 13 while meshed with the fourth speed drive gear 17A, and is disposed adjacent to the second speed driven gear 15B.

  On the other hand, the reverse driven gear 18B is rotatably fitted to the first driven shaft 13, and an idle gear 18C is disposed between the reverse driven gear 18B and the reverse drive gear 18A, and the reverse drive gear 18A rotates. The direction and the rotation direction of the reverse drive gear 18 are the same. Accordingly, the first through fourth gear pairs 14, 15, 16, and 17 correspond to the forward speed transmission mechanism, and the reverse gear pair 18 corresponds to the reverse speed transmission mechanism.

  A switching mechanism is provided for making these gear pairs 14, 15, 16, 17, and 18 selectively transmit power. This switching mechanism is a mechanism that selectively couples each gear pair 14, 15, 16, 17, 18 to any one of the drive shafts 4, 11 and the first driven shaft 13, and therefore a conventional manual transmission or the like. A synchronous coupling mechanism (synchronizer) can be used, or a mesh clutch (dog clutch), a friction clutch, or the like can be used. Further, when the driven gear is integrally attached to the first driven shaft 13, the drive gear is rotatable with respect to the drive shaft, and the drive gear is selectively connected to the drive shaft. A switching mechanism can be provided on the drive shaft side.

  In the example shown in FIG. 1, a synchronous coupling mechanism is used as a switching mechanism, a first sync 19 is arranged between the first speed driven gear 14B and the third speed driven gear 16B, and a reverse driven gear. A second sync 20 is disposed between 18B and the fourth speed driven gear 17B, and a start (S) sync 21 is provided adjacent to the second speed driven gear 15B. These synchros 19, 20, and 21 are the same as those used in conventional manual transmissions, and a sleeve is spline-fitted to a hub integrated with the first driven shaft 13, and the sleeve is moved in the axial direction. A chamfer or spline that gradually fits by spline by moving is integrally provided in each driven gear, and a ring that synchronizes rotation by gradually frictionally contacting a predetermined member on the driven gear side as the sleeve moves. Is provided.

  Therefore, the first sync 19 moves the sleeve 19S to the right side of FIG. 1 to connect the first speed driven gear 14B to the first driven shaft 13 and moves the sleeve 19S to the left side of FIG. The third speed driven gear 16B is connected to the first driven shaft 13, and the sleeve 19S is positioned at the center so that the driven gears 14B and 16B are not engaged with each other and are in a neutral state. . Further, the second synchro 20 moves the sleeve 20S to the right side in FIG. 1 to connect the reverse driven gear 18B to the first driven shaft 13, and moves the sleeve 20S to the left side in FIG. The fourth speed driven gear 17B is connected to the first driven shaft 13, and the sleeve 20S is positioned at the center, so that the driven gear 18B and 17B are not engaged with each other and are in a neutral state.

  The start sync 21 corresponds to the starting switching mechanism of the present invention, and includes a sleeve 21S that is spline-fitted to a hub integrated with the first driven shaft 13, and second sleeves on both sides of the sleeve 21S. A speed driven gear 15B and a spline integrated with a second driven shaft 23 connected to the third drive shaft 12 via a starting transmission mechanism 22 are disposed. Therefore, by moving the sleeve 21S in the axial direction, the sleeve 21S is fitted into one of the splines and connected to the second speed driven gear 15B or the second driven shaft 23.

  Therefore, the start sync 21 moves the sleeve 21S to the right side of FIG. 1 to connect the second speed driven gear 15B to the first driven shaft 13 and moves the sleeve 21S to the left side of FIG. By connecting the 2 driven shaft 23 to the first driven shaft 13 and further positioning the sleeve 21S in the center, the second driven shaft 15B is not engaged with the second driven gear 15B or the second driven shaft 23, and a neutral state is established. ing.

  Here, the starting transmission mechanism 22 will be described. The starting transmission mechanism 22 amplifies the torque output from the second pump motor 8 and transmits it to the first driven shaft 13 when the vehicle starts. It is a mechanism provided. Specifically, the counter drive gear 22A is attached to the rotor shaft 8A for sending and receiving power to the second pump motor 8 and the third drive shaft 12 connected to the sun gear S2 of the second planetary gear mechanism 7. A counter driven gear 22B meshing with the counter drive gear 22A is attached to the second driven shaft 23. The third counter gear pair 22 composed of the counter drive gear 22A and the counter driven gear 22B has a counter drive gear 22A with a smaller number of teeth than the counter driven gear 22B, in other words, a second driven gear pair 22B. The counter driven gear 22 </ b> B that rotates integrally with the shaft 23 is configured as a speed reduction mechanism having a gear ratio that makes the rotation speed higher than that of the counter drive gear 22 </ b> A that rotates integrally with the third drive shaft 12.

  That is, in the configuration example shown in FIG. 1, the starting transmission mechanism 22 is a third counter having a gear ratio in which the rotational speed of the third drive shaft 12 is higher than the rotational speed of the second driven shaft 23. A speed reduction mechanism comprising a gear pair 22 is used. Therefore, the starting transmission mechanism 22 decelerates the rotational speed of the output torque of the second pump motor 8 input to the third drive shaft 12 and transmits it to the second driven shaft 23, that is, the third drive shaft 12. Can be amplified and transmitted to the second driven shaft 23.

  The power transmitted by amplifying the output torque of the second pump motor 8 and transmitted to the second driven shaft 23 moves the sleeve 21S of the start sync 21 to the left side of FIG. 1, and the second driven shaft 23 and the first driven shaft 23 are driven. By connecting the shaft 13, it is possible to transmit to the first driven shaft 13. That is, when the vehicle starts, the second driven shaft 23 and the first driven shaft 13 are connected to amplify the torque output from the second pump motor 8 and add it to the torque output from the transmission. Can do. In other words, when the vehicle starts, the output torque of the second pump motor 8 can be amplified and directly transmitted to the first driven shaft 13, and the first planetary gear mechanism 5, the first drive shaft 4, and the first speed gear can be transmitted. Together with the power transmission system in which power is transmitted to the first driven shaft 13 via the pair 14, two power transmission systems can be established. As a result, the driving force can be increased sufficiently and sufficiently at the time of starting.

  Each of the sleeves 19S, 20S, and 21S can be configured to be switched by manual operation via a linkage (not shown), or can be switched by an actuator (not shown) provided individually. It can be configured to be. Further, the pushing volumes of the pump motors 6 and 8 or the operation of the actuators are electrically controlled by an electronic control unit (ECU) (not shown). This electronic control unit is mainly composed of a microcomputer, and performs calculations in accordance with input data, prestored data and programs, sets the extrusion volume, or operates the synchros 19, 20, and 21. The command signal is output.

  The hydraulic circuit relating to the pump motors 6 and 8 will be briefly described. As shown in FIG. 2, the pump motors 6 and 8 are connected by a closed circuit. That is, the suction ports 6S and 8S of the pump motors 6 and 8 are communicated with each other by the oil passage 24, and the discharge ports 6D and 8D are communicated with each other through the oil passage 25. The suction port is a port that has a relatively low pressure when the extrusion volume is set so as to apply a reaction force to the planetary gear mechanism during forward traveling, and on the contrary, a relatively high pressure. The port that becomes is the discharge port. In the hydraulic closed circuit configured as described above, inevitable leakage of the pressure oil occurs, so that the charge pump 3 described above may be connected to the above closed circuit in order to replenish the pressure oil. .

  Next, the operation of the transmission described above will be described. FIG. 3 shows the first and second pump motors (PM1, PM2) 6, 8 when setting the respective gears determined by the gear ratio of any one of the gear pairs 14, 15, 16, 17, 18, and FIG. 3 is a chart collectively showing the operating states of the synchros 19, 20, and 21. “0” for each pump motor 6 and 8 in FIG. 3 indicates that the pump capacity (extrusion volume) is substantially zero, and the rotor No pressure oil is generated even if the shaft is rotated, and the output shaft does not rotate (free) even if hydraulic pressure is supplied. “LOCK” indicates that the rotor is stopped rotating. ing. Further, “PUMP” indicates a state in which the pump capacity is made larger than substantially zero and the pressure oil is discharged, and accordingly, the corresponding first or second pump motor 6 or 8 functions as a pump. “MOTOR” indicates a state in which pressure oil discharged from one of the pump motors 6 (or 8) is supplied and functions as a motor. Therefore, the corresponding hydraulic pump motor 8 (or 6) has a shaft torque. It has occurred.

  The “right” and “left” for each of the synchros 19, 20, and 21 indicate the positions of the respective sleeves 19S, 20S, and 21S in FIG. 1, and the parentheses indicate a standby state for downshifting, a key. The parentheses indicate a standby state for upshifting, and “N” indicates a state in which the corresponding synchros 19, 20, and 21 are set to the OFF state (neutral position), and italic “N” reduces dragging. Therefore, it indicates that the OFF state (neutral position) is set.

  When the neutral position is selected and the neutral state is set, the extrusion volumes of the pump motors 6 and 8 are set to zero, and the synchros 19, 20, and 21 are turned off. That is, each sleeve 19S, 20S, 21S is set at the center position. Accordingly, none of the gear pairs 14, 15, 16, 17, 18 is in a neutral state that is not connected to the first driven shaft 13. As a result, the pump motors 6 and 8 are in a so-called idle state. Therefore, even if torque is transmitted from the engine 1 to the ring gears R1 and R2 of the planetary gear mechanisms 5 and 7, no reaction force acts on the sun gears S1 and S2, so that the planetary gear mechanisms 5 and 7 are connected to the carriers C1 and C2 that are output elements. Torque is not transmitted to each drive shaft 4, 11.

  When the shift position is switched to a travel position such as a drive position, the sleeve 19S of the first sync 19 is moved to the right in FIG. 1, and the sleeve 21S of the start sync 21 is moved to the left in FIG. Accordingly, the first speed driven gear 14B and the second driven shaft 23 are connected to the first driven shaft 13, respectively. As a result, the first drive shaft 4 and the first driven shaft 13 are connected via the first speed gear pair 14. Connected. That is, the connected state of the gear pair is a state where the first speed is set. Further, since the second driven shaft 23 is connected to the first driven shaft 13, the third drive shaft 12 and the first driven shaft 13 are connected via the third counter gear pair 22, that is, the rotor of the second pump motor 8. The shaft 8A and the first driven shaft 13 are coupled so as to be able to transmit torque.

  In this state, since the vehicle is still stopped, in each of the planetary gear mechanisms 5 and 7, power is input from the engine 1 to the ring gears R1 and R2 while the carriers C1 and C2 are stopped. S2 rotates in a direction opposite to the rotation direction of the ring gears R1 and R2. In this state, the extrusion volumes of the pump motors 6 and 8 are gradually increased. First, the first pump motor 6 is caused to function as a pump to generate hydraulic pressure. Then, since the reaction force accompanying it acts on the sun gear S1 in the first planetary gear mechanism 5, a torque appears to rotate the carrier C1 in the same direction as the ring gear R1. As a result, power is transmitted to the first driven shaft 13 via the first speed gear pair 14.

  Since the first pump motor 6 rotates in reverse so as to function as a pump, pressure oil is discharged from the suction port 6S and supplied to the suction port 8S of the second pump motor 8. As a result, the second pump motor 8 functions as a motor, and a torque in the so-called forward rotation direction is output from the rotor shaft 8A. The torque is output from the third drive shaft 12 and the third counter gear pair 22 (that is, the starting transmission mechanism). 22) and the second driven shaft 23 to the first driven shaft 13. That is, the torque output from the second pump motor 8 is amplified and transmitted to the first driven shaft 13.

  Accordingly, a part of the power input from the engine 1 is transmitted to the first driven shaft 13 via the first planetary gear mechanism 5 and the first speed gear pair 14, and the other power is in the form of a flow of pressure oil. The energy is converted and transmitted to the second pump motor 8, and torque is amplified and transmitted from the second pump motor 8 to the first driven shaft 13. In this way, at the time of starting, so-called mechanical power transmission and power transmission through the fluid are performed. In addition, torque is amplified at the time of power transmission through the fluid, and the sum of these powers is the first power. It is output to the driven shaft 13. Therefore, a larger driving torque can be obtained at the time of starting of a vehicle that requires a large driving force, and the starting acceleration of the vehicle can be improved.

  In such a power transmission state, the torque appearing on the first driven shaft 13 is larger than the torque in the case of only mechanical transmission via the first speed gear pair 14, and therefore the overall transmission ratio of the transmission is Therefore, it becomes larger than the so-called fixed speed ratio determined by the first speed gear pair 14. Further, the gear ratio changes in accordance with the transmission ratio of power through the fluid. Therefore, as the rotational speed of the sun gear S1 in the first planetary gear mechanism 5 and the first pump motor 6 connected to the sun gear S1 gradually approaches zero, the rate of power transmission through the fluid decreases, and the transmission as a whole. Is close to the fixed speed ratio of the first speed. And the extrusion volume of the 1st pump motor 6 increases to the maximum, and that rotation stops, and it becomes the 1st speed which is a fixed gear ratio.

  In this state, the extrusion volume of the second pump motor 8 is set to zero, so that the second pump motor 8 idles and the first pump motor 6 is locked to stop its rotation. That is, since the closed circuit connecting the pump motors 6 and 8 is closed by the second pump motor 8, the first pump motor 6 having the maximum extrusion volume can supply and discharge the pressure oil. Disappears and its rotation is stopped. As a result, a torque for fixing the sun gear S1 of the first planetary gear mechanism 5 acts. Therefore, in the first planetary gear mechanism 5, power is input to the ring gear R1 while the sun gear S1 is fixed. Therefore, a torque is generated in the carrier C1, which is an output element, to rotate it in the same direction as the ring gear R1. It is transmitted to the first driven shaft 13 as the output shaft via the 1 drive shaft 4 and the first speed gear pair 14. Thus, the first speed that is the fixed gear ratio is set.

  If the start sync 21 is set to the OFF state in the first speed state, that is, if the sleeve 21S is set to the neutral position, the second pump motor 8 will not be rotated, so that power loss due to so-called drag is avoided. can do. Further, while the sleeve 19S of the first sync 19 is moved to the right side in FIG. 1, the sleeve 21S of the start sync 21 is moved to the right side in FIG. 1, and the second speed driven gear 15B of the second speed gear pair 15 is moved. When coupled to the first driven shaft 13, the carrier C 2 that is the output element of the second planetary gear mechanism 7 is driven through the second counter gear pair 10, the second drive shaft 11, and the second speed gear pair 15. Since it is connected to the shaft 13, it is in a state of waiting for an upshift to the second speed, which is a fixed gear ratio. On the other hand, if the sleeve 21S of the start sync 21 is moved to the left side in FIG. 1 so that torque can be transmitted between the rotor shaft 8A of the second pump motor 8 and the first driven shaft 13, the first speed is increased. A downshift standby state is set in which a large gear ratio is set.

  In the upshift standby state from the first speed to the second speed, the second pump motor 8 and the sun gear S2 connected thereto rotate in the opposite direction to the ring gear R2. Therefore, when the extrusion volume of the second pump motor 8 is increased in the positive direction, the second pump motor 8 functions as a pump, and a reaction force associated therewith acts on the sun gear S2. As a result, a torque obtained by synthesizing the torque input to the ring gear R2 and the reaction force acting on the sun gear S2 acts on the carrier C2, which rotates in the forward direction, and the rotational speed gradually increases. In other words, the rotational speed of the engine 1 is gradually reduced. Torque is transmitted from the carrier C2 to the first driven shaft 13 through the second counter gear pair 10, the second drive shaft 11, and the second speed gear pair 15.

  Pressure oil generated when the second pump motor 8 functions as a pump is supplied from the suction port 8S to the suction port 6S of the first pump motor 6. Therefore, the first pump motor 6 functions as a motor and outputs torque in the forward rotation direction, which acts on the sun gear S 1 of the first planetary gear mechanism 5. Since power is input from the engine 1 to the ring gear R1 of the first planetary gear mechanism 5, the torque and torque acting on the sun gear S1 are combined and output from the carrier C1 to the first drive shaft 4. In other words, power transmission via hydraulic pressure occurs in parallel with mechanical power transmission, and the first driven shaft 13 is transmitted with the combined power. Then, as the rotational speed of the second pump motor 8 gradually decreases, the ratio of mechanical power transmission through the second planetary gear mechanism 7 and the second speed gear pair 15 gradually increases, and the transmission as a whole is increased. The speed ratio gradually decreases from the speed ratio determined by the first speed gear pair 14 to the speed ratio determined by the second speed gear pair 15. The change is a continuous change as in the case of changing to the first speed, which is a fixed gear ratio, after starting. That is, continuously variable transmission is achieved. And the extrusion volume of the 2nd pump motor 8 increases to the maximum, and that rotation stops, and it becomes the 2nd speed which is a fixed gear ratio.

  In this state, the extrusion volume of the first pump motor 6 is set to zero, so that the first pump motor 6 idles and the second pump motor 8 is locked to stop its rotation. That is, since the closed circuit connecting the pump motors 6 and 8 is closed by the first pump motor 6, the second pump motor 8 having the maximum extrusion volume can supply and discharge the pressure oil. Disappears and its rotation is stopped. As a result, a torque for fixing the sun gear S2 of the second planetary gear mechanism 7 acts. Therefore, in the second planetary gear mechanism 7, since power is input to the ring gear R2 while the sun gear S2 is fixed, the carrier C2, which is an output element, generates torque that rotates it in the same direction as the ring gear R2. It is transmitted to the first driven shaft 13 as the output shaft through the two counter gear pair 10, the second drive shaft 11 and the second speed gear pair 15. Thus, the second speed, which is a fixed gear ratio, is set.

  If the first sync 19 is set to the OFF state in the second speed state, that is, if the sleeve 19S is set to the neutral position, the first pump motor 6 is not rotated, so that the power loss due to so-called drag is reduced. It can be avoided. Further, when the sleeve 19S of the first synchro 19 is moved to the left in FIG. 1 and the third speed driven gear 16B is connected to the first driven shaft 13, an upshift standby state to the third speed, which is a fixed gear ratio, is achieved. Become. On the other hand, if the sleeve 19S of the first synchro 19 is moved to the right side in FIG. 1 and the first speed driven gear 14B is connected to the first driven shaft 13, a downshift standby state to the first speed is established.

  In the upshift standby state from the second speed to the third speed, the first pump motor 6 and the sun gear S1 connected thereto rotate in the opposite direction to the ring gear R1. Therefore, when the extrusion volume of the first pump motor 6 is increased in the positive direction, the first pump motor 6 functions as a pump, and the reaction force associated therewith acts on the sun gear S1. As a result, a torque obtained by synthesizing the torque input to the ring gear R1 and the reaction force acting on the sun gear S1 acts on the carrier C1 and rotates in the forward direction, and the torque rotates to the first drive shaft 4 and the third speed gear pair 16. Is transmitted to the first driven shaft 13 which is the output shaft. Further, the rotational speed of the engine 1 is gradually reduced as the speed ratio decreases.

  Pressure oil generated when the first pump motor 6 functions as a pump is supplied from the suction port 6S to the suction port 8S of the second pump motor 8. Therefore, the second pump motor 8 functions as a motor and outputs torque in the forward rotation direction, which acts on the sun gear S2 of the second planetary gear mechanism 7. Since the power is input from the engine 1 to the ring gear R2 of the second planetary gear mechanism 7, the torque and the torque acting on the sun gear S2 are combined and the second counter gear pair 10 is supplied from the carrier C2 through the second counter gear pair 10. Output to the drive shaft 11. In other words, power transmission via hydraulic pressure occurs in parallel with mechanical power transmission, and the first driven shaft 13 is transmitted with the combined power. As the rotational speed of the first pump motor 6 gradually decreases, the ratio of mechanical power transmission through the first planetary gear mechanism 5 and the third speed gear pair 16 gradually increases, and the transmission as a whole is increased. The speed ratio gradually decreases from the speed ratio determined by the second speed gear pair 15 to the speed ratio determined by the third speed gear pair 16. The change is a continuous change as in the case of changing to the first speed that is the fixed gear ratio after the start and the case of upshifting from the first speed to the second speed. That is, continuously variable transmission is achieved. And when the extrusion volume of the 1st pump motor 6 increases to the maximum and the rotation stops, it becomes the 3rd speed which is a fixed gear ratio.

  In this state, the extrusion volume of the second pump motor 8 is set to zero, so that the second pump motor 8 idles and the first pump motor 6 is locked to stop its rotation. That is, since the closed circuit connecting the pump motors 6 and 8 is closed by the second pump motor 8, the first pump motor 6 having the maximum extrusion volume can supply and discharge the pressure oil. Disappears and its rotation is stopped. As a result, a torque for fixing the sun gear S1 of the first planetary gear mechanism 5 acts. Therefore, in the first planetary gear mechanism 5, power is input to the ring gear R1 while the sun gear S1 is fixed. Therefore, a torque is generated in the carrier C1, which is an output element, to rotate it in the same direction as the ring gear R1. It is transmitted to the first driven shaft 13 as the output shaft through the 1 drive shaft 4 and the third speed gear pair 16. Thus, the third speed, which is a fixed gear ratio, is set.

  If the second sync 20 and the start sync 21 are set to the OFF state in this third speed state, that is, if the sleeve 20S and the sleeve 21S are set to the neutral positions, the second pump motor 8 can be rotated. Therefore, power loss due to so-called dragging can be avoided. If the sleeve 20S of the second sync 20 is moved to the left in FIG. 1 and the fourth driven gear 17B is connected to the first driven shaft 13 with the start sync 21 set to the OFF state, the fixed gear ratio is obtained. It becomes the upshift waiting state to the 4th speed which is. On the other hand, if the sleeve 21S of the start sync 21 is moved to the right side in FIG. 1 while the second sync 20 is set to the OFF state, the second driven gear 15B is connected to the first driven shaft 13, so that It becomes a downshift standby state to the 2nd speed.

  In the upshift standby state from the third speed to the fourth speed, the second pump motor 8 and the sun gear S2 connected thereto rotate in the opposite direction to the ring gear R2. Therefore, when the extrusion volume of the second pump motor 8 is increased in the positive direction, the second pump motor 8 functions as a pump, and a reaction force associated therewith acts on the sun gear S2. As a result, a torque obtained by synthesizing the torque input to the ring gear R2 and the reaction force acting on the sun gear S2 acts on the carrier C2 and rotates forward, and the torque is transmitted to the second drive via the second counter gear pair 10. It is transmitted to the shaft 11 and further transmitted to the first driven shaft 13 that is the output shaft via the fourth speed gear pair 17. Further, the rotational speed of the engine 1 is gradually reduced as the speed ratio decreases.

  Pressure oil generated when the second pump motor 8 functions as a pump is supplied from the suction port 8S to the suction port 6S of the first pump motor 6. Therefore, the first pump motor 6 functions as a motor and outputs torque in the forward rotation direction, which acts on the sun gear S 1 of the first planetary gear mechanism 5. Since power is input from the engine 1 to the ring gear R1 of the first planetary gear mechanism 5, the torque and torque acting on the sun gear S1 are combined and output from the carrier C1 to the first drive shaft 4. In other words, power transmission via hydraulic pressure occurs in parallel with mechanical power transmission, and the first driven shaft 13 is transmitted with the combined power. As the rotational speed of the second pump motor 8 gradually decreases, the rate of mechanical power transmission through the second planetary gear mechanism 7 and the fourth speed gear pair 17 gradually increases, and the transmission as a whole is increased. The speed ratio gradually decreases from the speed ratio determined by the third speed gear pair 16 to the speed ratio determined by the fourth speed gear pair 17. The change is a continuous change, similar to the shift between the fixed gear ratios described above. That is, continuously variable transmission is achieved. And when the extrusion volume of the 2nd pump motor 8 increases to the maximum and the rotation stops, it becomes the 4th speed which is a fixed gear ratio.

  In this state, the extrusion volume of the first pump motor 6 is set to zero, so that the first pump motor 6 idles and the second pump motor 8 is locked to stop its rotation. That is, since the closed circuit connecting the pump motors 6 and 8 is closed by the first pump motor 6, the second pump motor 8 having the maximum extrusion volume can supply and discharge the pressure oil. Disappears and its rotation is stopped. As a result, a torque for fixing the sun gear S2 of the second planetary gear mechanism 7 acts. Therefore, in the second planetary gear mechanism 7, since power is input to the ring gear R2 while the sun gear S2 is fixed, the carrier C2, which is an output element, generates torque that rotates it in the same direction as the ring gear R2. It is transmitted to the second drive shaft 11 via the two counter gear pair 10 and further transmitted to the first driven shaft 13 as the output shaft via the fourth speed gear pair 17. Thus, the fourth speed, which is a fixed gear ratio, is set.

  If the first sync 19 is set to the OFF state in the fourth speed state, that is, if the sleeve 19S is set to the neutral position, the first pump motor 6 will not be rotated, so that the power loss due to so-called drag is reduced. It can be avoided. Further, if the sleeve 19S of the first synchro 19 is moved to the left side in FIG. 1 and the third speed driven gear 16B is connected to the first driven shaft 13, a state of waiting for a downshift to the third speed is established.

  Next, the reverse gear will be described. When an instruction to set the reverse gear is issued, for example, when the shift position is switched from the neutral position to the reverse position, the sleeve 21S of the start sync 21 is moved to the left in FIG. Torque can be transmitted to and from the driven shaft 13, and the sleeve 20 </ b> S of the second synchro 20 is moved to the right in FIG. 1, and the reverse driven gear 18 </ b> B is coupled to the first driven shaft 13. That is, the power from the rotor shaft 8A of the second pump motor 8 to the first driven shaft 13 via the third drive shaft 12, the third counter gear pair 22 (starting transmission mechanism 22) and the second driven shaft 23. A transmission path is formed.

  In this state, the extrusion volume of the first pump motor 6 is gradually increased. Further, the extrusion volume of the second pump motor 8 is gradually increased in the negative direction opposite to the above-described forward stage (forward travel). Since the first driven shaft 13 does not rotate when the vehicle is stopped, the second pump motor 8 connected thereto is stopped. On the other hand, in the first planetary gear mechanism 5, power is input from the engine 1 to the ring gear R1 in a state where the carrier C1 connected to the first drive shaft 4 is fixed. The first pump motor 6 is rotating in the opposite direction to the ring gear R1.

  Therefore, when the torque capacity of the first pump motor 6 is gradually increased, the first pump motor 6 functions as a pump and generates hydraulic pressure. The accompanying reaction force acts on the sun gear S <b> 1, so that a torque is generated in the carrier C <b> 1 that is an output element in the same direction as when traveling forward, and this is transmitted to the first drive shaft 4. Since the reverse gear pair 18 disposed between the first drive shaft 4 and the first driven shaft 13 includes an idle gear 18C, when the first drive shaft 4 rotates in the same direction as during forward travel. The first driven shaft 13 rotates in the opposite direction and therefore travels backward.

  Further, the pressure oil generated when the first pump motor 6 functions as a pump is supplied from the suction port 6S to the suction port 8S of the second pump motor 8. Since the extrusion volume of the second pump motor 8 is set to the negative side as described above, the second pump motor 8 is supplied in a direction opposite to that during forward traveling by supplying pressure oil to the suction port 8S. The torque is transmitted to the first driven shaft 13 through the third drive shaft 12 and the third counter gear pair 22 (starting transmission mechanism 22) and the second driven shaft 23. That is, the torque output from the second pump motor 8 is amplified and transmitted to the first driven shaft 13.

  Accordingly, a part of the power input from the engine 1 is transmitted to the first driven shaft 13 through the first planetary gear mechanism 5 and the reverse gear pair 18, and the other power is converted into energy in the form of pressure oil flow. This is transmitted to the second pump motor 8, and torque is further amplified and transmitted from the second pump motor 8 to the first driven shaft 13. That is, during reverse travel, as in the case of starting in the forward direction, so-called mechanical power transmission and power transmission via fluid are performed, and torque is amplified during power transmission via fluid. The power obtained by adding these powers is output to the first driven shaft 13. Therefore, as in the case of starting in the forward direction, a larger driving torque can be obtained even when starting in the backward direction of the vehicle that requires a large driving force.

  Then, by gradually increasing the extrusion volume of the first pump motor 6, the number of rotations thereof gradually decreases, and accordingly, the rate of power transmission via the fluid gradually decreases, so the transmission ratio is the gear of the reverse gear pair 18. It gradually decreases to a gear ratio determined by the ratio. That is, the gear ratio changes continuously. Then, the reverse speed is set as a fixed gear ratio by maximizing the extrusion volume of each pump motor 6, 8.

  As described above, in the transmission shown in FIG. 1, the forward gear ratio and the reverse gear ratio can be set as so-called fixed gear ratios that can be set without fluid transmission, and the gear ratio between these fixed gear ratios can be set. Can be set continuously, and therefore a continuously variable transmission having a wide speed ratio width as a whole can be performed. Further, the axis line on which the rotary shafts such as the drive shafts 4 and 11, the first driven shaft 13, the planetary gear mechanisms 5 and 7, and the pump motors 6 and 8 are arranged is a part where the third drive shaft 12 is arranged. Since the main part of the transmission excluding the shaft has a so-called two-shaft configuration with two axes, it is possible to reduce the overall configuration by reducing the outer diameter as a whole, and to each planetary gear mechanism 5. 7 and the pump motors 6 and 8 are arranged adjacent to each other, that is, without being staggered in the axial direction, so that the length of the transmission in the axial direction can be shortened to The configuration can be reduced in size. In addition, since power can be output on an extension line of the rotation center axis of the engine 1 or on an axis parallel to the extension line, a transmission that is particularly excellent in in-vehicle use for an FR vehicle can be obtained.

  In addition, when starting in the forward direction and the reverse direction, the second pump motor 8 is connected to the first driven shaft 13 via the starting transmission mechanism 22 by the start sync 21 in addition to mechanical power transmission. Thus, the power can be transmitted to the first driven shaft 13 by amplifying the torque by the power transmission via the fluid. Since the start sync 21, that is, the start switching mechanism 21 is operated in this way, the speed ratio at the time of start becomes even greater than the speed ratio determined by the first speed gear pair 14 and the reverse gear pair 18 having a large gear ratio, As a result, the starting acceleration can be improved by relatively increasing the driving torque at the time of starting.

  And when setting each fixed gear ratio as a forward gear with the above-mentioned transmission, since the extrusion volume of one of the pump motors 6 and 8 is set to zero and the other pump motors 8 and 6 are locked accordingly, Fluid transmission is not performed at these fixed speed ratios. That is, power can be transmitted without converting the energy form, and no energy is required to maintain the power transmission path in a state where power can be transmitted. Can be improved.

  Further, in the configuration shown in FIG. 1, the pump motors 6 and 8 each have a so-called single-out structure in which the rotor shafts 6A and 8A both project only in one axial direction. Therefore, each pump motor 6 and 8 can be made small and highly reliable with a simple configuration.

  Next, another specific example of the present invention will be described. Each specific example described below is obtained by changing a part of the configuration shown in FIG. 1 described above. Therefore, in the following description, a different part from the configuration in FIG. 1 will be described, and the configuration shown in FIG. The same reference numerals as those in FIG. 1 are attached to the same parts as those in FIG.

  The example shown in FIG. 4 is an example in which the second counter gear pair 10 and the second speed gear pair 15 in the example shown in FIG. That is, in the example shown in FIG. 4, the second counter gear pair 10 and the second speed gear pair 15 in the example shown in FIG. 1 are combined with the second counter gear pair 26. The configuration of the second counter gear pair 26 is the same as that of the second counter gear pair 10 in FIG. 1, and the counter drive gear 26A of the second counter gear pair 26 is attached to the carrier C2 of the second planetary gear mechanism 7. A counter driven gear 26C meshed with the second drive shaft 11 via an idle gear 26B is connected to the second drive shaft 11. That is, the second drive shaft 11 is connected to the carrier C2 via the second counter gear pair 26.

  Therefore, the counter driven gear 26C also serves as the second speed drive gear 26C, and the idle gear 26B serves as the second speed driven gear 26B. The second counter gear pair 26, like the second counter gear pair 10 described above, constitutes a so-called output transmission mechanism, which uses a transmission mechanism using a friction wheel, a chain or a belt, and the like. It is also possible to replace it with a wrapping transmission mechanism.

  As the second counter gear pair 26 serves as both the second counter gear pair 10 and the second speed gear pair 15 in the example shown in FIG. 1, the second drive shaft 11 has a distal end side (FIG. 4). Only the fourth speed drive gear 17A and the counter driven gear 26C are attached in order from the right side). Therefore, when configured as in the example shown in FIG. 4, compared with the example in which the fourth drive gear 17 </ b> A, the second drive gear 15 </ b> A, and the counter driven gear 10 </ b> C are attached to the second drive shaft 11, The number of gear pairs can be reduced, and the overall length of the hollow second drive shaft 11 can be shortened. Therefore, the structure of the double shaft structure composed of the second drive shaft 11 and the first drive shaft 4 can be simplified, and the transmission can be reduced in size, weight, and cost. Further, by reducing the number of counter gear pairs, it is possible to reduce gear meshing loss or friction loss as a whole transmission and improve power transmission efficiency.

  Further, the arrangement of the start sync 21 (starting switching mechanism 21) is changed as the second counter gear pair 26 serves as both the second counter gear pair 10 and the second speed gear pair 15 in the example shown in FIG. Has been. That is, in the example shown in FIG. 1, the engine of the third counter gear pair 22 (starting transmission mechanism 22) is provided between the third counter gear pair 22 (starting transmission mechanism 22) and the second speed gear pair 15. In the example shown in FIG. 4, the start sync 21 (starting switching mechanism 21) arranged adjacent to the side far from 1 (the right side in FIG. 1) is a third counter gear pair 22 (starting transmission mechanism 22). ) And the second counter gear pair 26, that is, adjacent to the side close to the engine 1 (the left side in FIG. 4) of the third counter gear pair 22 (starting transmission mechanism 22). In addition, according to said change, the 2nd driven shaft 23 becomes a hollow structure, and becomes a structure which mutually fits to the outer peripheral side of the 1st driven shaft 13 so that rotation is possible.

  Therefore, splines integrated with the second driven shaft 23 and the idle gear 26B of the second counter gear pair 26 are arranged on both sides of the sleeve 21S of the start sync 21. Therefore, when the sleeve 21S is moved in the axial direction, the sleeve 21S is fitted to one of the splines and is connected to the second driven shaft 23 or the idle gear 26B.

  That is, the start sync 21 moves the sleeve 21S to the right side of FIG. 4 to connect the second driven shaft 23 to the first driven shaft 13 and moves the sleeve 21S to the left side of FIG. The gear 26B, that is, the second speed driven gear 26B is connected to the first driven shaft 13, and the sleeve 21S is positioned at the center, so that the neutral state is established without engaging with the second driven shaft 23 or the second speed driven gear 26B. It is comprised so that it may become.

  As described above, even in the case of the configuration shown in the example shown in FIG. 4, it is possible to set four forward speeds and one reverse speed as the fixed gear ratio. The operation states of the synchros 19, 20, and 21 and the operation states of the pump motors 6 and 8 for setting the fixed gear ratio and the intermediate gear ratio are collectively shown in FIG. The meaning of each symbol in FIG. 5 is the same as the meaning of each symbol in FIG. 3 described above.

  4 differs from the example shown in FIG. 1 in that the second counter gear pair 10 and the second speed gear pair 15 are also used as the second counter gear pair 26, so The engagement position between the first driven shaft 13 and the second driven shaft 23 and the engagement position between the first driven shaft 13 and the second driven gear are interchanged with each other. Therefore, in the chart shown in FIG. In the chart of FIG. 3, “Left” in the column of the start sync 21 is replaced with “Right”, “Right” is replaced with “Left”, and the other columns in FIG. 5 are the same as those in FIG.

  As shown in FIG. 5, in the transmission having the configuration shown in FIG. 4, the pump motors 6 and 8 operate in the same manner as the transmission having the configuration shown in FIG. The operations of the planetary gear mechanisms 5 and 7 associated with the operations of, 8 are the same as those of the transmission having the configuration shown in FIG. Omitted. And even if it is a case where it is comprised as shown in FIG. 4, like the transmission of the structure shown in FIG. 1, the whole structure can be reduced in size to improve the onboard performance, and the start acceleration can be improved. It is possible to improve the power transmission efficiency. Furthermore, each of the pump motors 6 and 8 can have a so-called single-out structure in which the rotor shafts 6A and 8A each protrude only in one axial direction, thereby simplifying the configuration and reducing the size. Moreover, the reliability can be improved.

  In each of the specific examples described above, the first driven shaft 13 is configured as an output shaft. However, in the present invention, an output shaft is provided separately from the first driven shaft 13, and power is supplied to the output shaft from the first driven shaft 13. May be transmitted and output from the transmission. In that case, the output shaft may be disposed on the same axis as the drive shafts 4 and 11 described above. Further, in the present invention, the first pump motor 6 can be configured as a so-called double swing type instead of the configuration where the second pump motor 8 is a so-called double swing type. Any one of them may be of the double swing type.

1 is a skeleton diagram schematically showing an example of a transmission according to the present invention. FIG. It is a schematic diagram for demonstrating the communication state of the pump motor. It is a graph which shows collectively the operation state of each hydraulic pump motor and each synchro at the time of setting each gear ratio. It is a skeleton figure which shows typically the other example of the transmission which concerns on this invention. FIG. 5 is a chart collectively showing operation states of hydraulic pump motors and synchros when setting respective gear ratios in the transmission configured as shown in FIG. 4.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Engine (power source), 2 ... Input shaft (input member), 4 ... 1st drive shaft, 5 ... 1st planetary gear mechanism (1st differential mechanism), S1 ... Sun gear, R1 ... Ring gear, C1 ... Carrier 6 ... 1st pump motor (1st motor), 7 ... 2nd planetary gear mechanism (2nd differential mechanism), S2 ... Sun gear, R2 ... Ring gear, C2 ... Carrier, 8 ... 2nd pump motor (2nd motor) 10 ... second counter gear pair, 11 ... second drive shaft, 12 ... third drive shaft, 13 ... first driven shaft, 14, 15, 16, 17, 18 ... first speed gear pair, second speed Gear pair, third speed gear pair, fourth speed gear pair, reverse gear pair (transmission mechanism), 19, 20... First sync, second sync (switching mechanism), 21... Start sync (start switching mechanism), 22 ... Third counter gear pair (Starting transmission mechanism), 23 ... second driven shaft, 24, 25 ... oil passage, 26 ... second counter gear pair, second speed gear pair.

Claims (8)

Between first to third drive shafts to which power is selectively transmitted from a power source, first driven shafts to which power is transmitted from each of these drive shafts, and between each of the drive shafts and the first driven shaft And a switching mechanism that selectively enables transmission of power between the drive shafts and the first driven shafts via the transmission mechanisms. In
The first drive shaft and the second drive shaft are arranged concentrically with each other so as to be relatively rotatable with each other, and the first drive shaft, the second drive shaft, and the first driven shaft are parallel to each other. Placed on the axis
A first differential mechanism having a first input element to which power is input from the power source, a first output element coupled to the first drive shaft, and a first reaction force element includes the first drive shaft and the first drive element. A first motor that is disposed on the same axis as the two drive shafts and that is capable of recovering energy and outputting driving force and having a variable recovery capacity and output capacity is coupled to the first reaction force element;
A second differential mechanism having a second input element to which power is input from the power source, a second output element coupled to the second drive shaft, and a second reaction force element includes the first drive shaft and the first drive shaft. A second motor that is disposed on an axis parallel to the two drive shafts and in parallel with the first differential mechanism, is capable of recovering energy and outputting driving force, and has a variable recovery capacity and output capacity Is coupled to the second reaction force element,
A starting transmission mechanism that is disposed on an axis parallel to the third drive shaft connected to the second reaction force element and that amplifies the torque of the third drive shaft and transmits the amplified torque to the second driven shaft; A vehicle transmission comprising a start switching mechanism that selectively connects the second driven shaft to the first driven shaft.   The transmission mechanism includes a plurality of mechanisms capable of setting a plurality of transmission gear ratios for the vehicle to travel, and the start switching mechanism is configured such that when there is a request to increase driving torque when the vehicle starts, A state where torque can be transmitted between the second driven shaft and the first driven shaft, and a state where torque cannot be transmitted between the second drive shaft and the first driven shaft, and the drive When there is no request for an increase in torque, either the torque cannot be transmitted between the second driven shaft and the first driven shaft, and any between the second drive shaft and the first driven shaft. The first driven shaft and the second driven shaft are configured to be in a state in which torque cannot be transmitted to any other shaft through the transmission mechanism. When The vehicle transmission according to claim 1 that.   3. The starting transmission mechanism includes a speed reduction mechanism having a gear ratio in which the rotational speed of the third drive shaft is higher than the rotational speed of the second driven shaft. The vehicle transmission described in 1.   The second differential mechanism is a single pinion type planetary gear mechanism having a sun gear, a ring gear arranged concentrically with the sun gear, and a carrier holding a pinion gear engaged with the sun gear and the ring gear. And the ring gear forms the second input element to which power is input from the power source, the carrier forms the second output element connected to the second drive shaft, and the sun gear is the first gear. The vehicle transmission according to any one of claims 1 to 3, wherein the second reaction force element connected to two motors is formed. The first motor is disposed on the same axis as the first differential mechanism and the first drive shaft and the second drive shaft,
The second motor is disposed on the same axis as the second differential mechanism and the third drive shaft and adjacent to the first motor on the outer side in the radial direction. The vehicle transmission according to any one of claims 1 to 4.   Each of the motors includes a variable displacement fluid pressure pump motor capable of changing an extrusion volume, and further includes a fluid circuit for communicating these variable displacement fluid pressure pump motors with each other. The vehicle transmission according to claim 5.   The vehicle transmission according to claim 6, wherein at least one of the variable displacement fluid pressure pump motors includes a double swing pump motor capable of changing the extrusion volume to both positive and negative.   6. The vehicle transmission according to claim 1, wherein each of the motors includes a motor / generator having a function as a generator and a function as an electric motor.

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