JP4923854B2 - Transmission control device - Google Patents

Description

  The present invention has at least two power transmission paths capable of changing the power transmission state according to the displacement volume of the variable displacement fluid pressure pump motor, and each variable displacement fluid pressure pump motor can exchange pressure fluid with each other. Therefore, the present invention relates to a transmission control device that can transmit power transmission via a fluid and, as a result, continuously change a gear ratio.

  The transmission selectively forms a plurality of power transmission paths between the input member and the output member, and makes the speed of rotation between the input member and the output member different by changing the acceleration / deceleration ratio in each power transmission path. It is a power transmission device configured to set a speed ratio as a ratio to a plurality of speed ratios. It is well known that this type of transmission is mounted on a vehicle. As a transmission for a vehicle, there are a large number of gear ratios that can be set, a small size and light weight, and power transmission efficiency. It is required to be expensive. Thus, for example, Patent Document 1 describes a transmission that can set seven or more shift stages and that can be downsized.

  The transmission described in Patent Document 1 is a so-called twin clutch type stepped transmission, which is connected to an engine via a first clutch and a first input shaft connected to the engine via a first clutch. The second input shaft, the output shaft, the auxiliary shaft connected to the first input shaft via a gear pair, and the first input shaft and the auxiliary shaft are provided and selectively engaged by the mesh clutch mechanism. And a plurality of gear pairs that are provided between the second input shaft and the output shaft and that are selectively connected by a meshing clutch mechanism. The transmission includes a gear stage that transmits torque from any one of the input shafts to the output shaft through a predetermined gear pair, and any output shaft from the input shaft to the output shaft through the predetermined gear pair and the sub shaft. It is configured to set a gear stage for transmitting torque, and as a result, it is configured to set seven or more gear stages including the reverse gear.

Japanese Patent Application Laid-Open No. 2003-120764

  In the transmission described in Patent Document 1 described above, since the number of shift speeds that can be set is large, the engine can be operated in a state with good fuel efficiency, and the auxiliary shaft is effectively used. The transmission is reduced in size and weight as a whole, and as a result, the fuel consumption of the vehicle can be improved.

  However, the first clutch and the second clutch used for setting and changing the power transmission path are constituted by a hydraulic friction clutch to absorb the inertial force at the time of shifting transition, Therefore, there is room for improvement in terms of energy efficiency and shift response. In other words, since the hydraulic friction clutch is engaged by pressing the friction plate with hydraulic pressure, the clutch is engaged even in a steady state where the vehicle is traveling with a predetermined gear set. It is necessary to generate the hydraulic pressure, and power for that is always consumed.

  In addition, the clutch that is not involved in the transmission of torque is controlled in a so-called released state, but drag torque is generated by relative rotation of the friction plate, and power loss is caused by the accompanying friction. In addition, since heat is generated at that time, it is necessary to always supply lubricating oil for cooling, and power is consumed for the lubrication, which may increase power loss.

  Further, when the clutch in the released state is engaged, after the clearance between the friction plates is clogged, the friction plates are substantially engaged to transmit torque. Therefore, the time until the clearance is blocked becomes a delay time. In particular, the transmission described in Patent Document 1 is a so-called clutch-to-clutch shift in which the release of one clutch and the engagement of the other clutch proceed in a coordinated manner. Thus, the engagement or disengagement is advanced, so that not only complicated control is forced, but also the shift response is not always good.

  The present invention has been made by paying attention to the above technical problems, and as a whole, the energy efficiency is good, the gear ratio can be continuously changed, and the gear change control according to the demand is possible. An object of the present invention is to provide a control device for a simple transmission.

  In order to achieve the above object, the invention according to claim 1 is provided with at least two power transmission paths from a power source to an output member, and the power is transmitted from one power transmission path to the other. In a transmission control device that changes the gear ratio by changing to a state in which power is transmitted through the power transmission path, the torque transmitted through each power transmission path is changed in accordance with the extrusion volume. The variable displacement fluid pressure pump motor provided for each power transmission path and communicated with each other so that pressure fluid can be exchanged between them, and the other displacement displacement fluid pressure pump motor with the extrusion volume fixed to the other A first speed change mode that sets the transmission ratio by changing the extrusion volume of the variable displacement fluid pressure pump motor, and a second speed change that sets the transmission ratio by changing each extrusion volume simultaneously and in opposite directions. Transmission control means for setting the transmission ratio in any one of a transmission mode and a third transmission mode for setting the transmission ratio by changing each extrusion volume simultaneously and in the same direction, and a vehicle equipped with the transmission. A travel determination unit that determines a travel state; and a shift mode selection unit that selects a shift mode to be executed by the shift control unit based on the travel state determined by the travel determination unit. To do.

  According to a second aspect of the present invention, in the first aspect of the invention, the shift mode selecting means determines that the travel determining means determines that the change width of the gear ratio is large or that a rapid shift is required. A transmission control apparatus comprising means for selecting the second shift mode.

  According to a third aspect of the present invention, in the first or second aspect of the invention, the speed change mode selecting means includes means for selecting the first speed change mode when a speed change ratio is set in the second speed change mode. The shift control means includes means for changing each extrusion volume so that the ratio of the change amount of each extrusion volume coincides with the ratio of each extrusion volume when switching from the second shift mode to the first shift mode. A transmission control device characterized by the above.

  According to a fourth aspect of the present invention, in the first aspect of the invention, the third speed change mode is a speed change mode in which each extrusion volume is changed so that a ratio of a change amount of each extrusion volume matches a ratio of each extrusion volume. This is a control device for a transmission.

  According to a fifth aspect of the present invention, in the fourth aspect of the invention, when the shift control means switches from the second shift mode to the third shift mode when switching to the first shift mode during the shift in the second shift mode. The transmission control device includes means for switching to the mode to execute the shift, and switching from the third shift mode to the first shift mode after one of the extrusion volumes reaches the maximum.

  According to a sixth aspect of the present invention, in any one of the first to fifth aspects, the shift control means performs a shift in the second shift mode from a state in which a gear ratio is set in the first shift mode. And a means for setting the extrusion volume of the fluid pressure pump motor to an extrusion volume that minimizes the amount of change from the current extrusion volume among the extrusion volumes that can set a target gear ratio. It is a control device.

  The invention according to claim 7 is the invention according to any one of claims 1 to 6, wherein each power transmission path is connected to an input element to which torque is transmitted from the power source and the variable displacement hydraulic pump motor. A differential mechanism having a reaction force element and an output element that outputs torque to the output member, and a transmission mechanism that is provided between the output element and the output member and has a different gear ratio for each power transmission path And a transmission control device.

  According to the first aspect of the present invention, the transmission torque in each power transmission path changes according to the extrusion volume of the variable displacement fluid pressure pump motor provided in each power transmission path. If the torque to be transmitted is zero and power is transmitted only through the other power transmission path, a gear ratio determined by the other power transmission path is set. In addition, since the variable displacement fluid pressure pump motors communicate with each other so that the pressure fluid can be exchanged between them, by operating any one of the variable displacement fluid pressure pump motors as a pump, Torque is mechanically transmitted to the output member via a power transmission path in which one variable displacement fluid pressure pump motor is provided, and the other variable displacement fluid pressure pump motor functions as a motor and the other Torque is transmitted to the output member via the power transmission path. That is, power transmission through the fluid occurs in parallel, and the torque transmitted through the fluid can be continuously changed, so that the transmission as a whole is a so-called continuously variable transmission.

  The gear ratio set by transmitting power through the fluid is determined by the extrusion volume of each variable displacement fluid pressure pump motor, but the extrusion volume is not limited to a constant value. That is, in a state where one extrusion volume is maximized, a predetermined transmission ratio can be set by setting the other extrusion volume to an intermediate value between the maximum and minimum, and the predetermined transmission ratio is determined based on each extrusion volume. Both can be set by setting an appropriate value between the maximum and the minimum. Therefore, when setting the transmission gear ratio, at least the first to third transmission modes are possible depending on how the extrusion volumes are changed. According to the invention of claim 1, these transmission modes are in the traveling state of the vehicle. Selected based on. Therefore, each extrusion volume is changed at the same time to perform a gear change with good responsiveness, the extrusion volume is changed so that the fluid pressure does not become high, and a gear shift with less power loss and good fuel consumption is performed. Is possible.

  According to the second aspect of the present invention, when a shift with a large change ratio of the gear ratio is required, or when a rapid shift is required, the speed is changed according to a shift mode in which the extrusion volumes are changed simultaneously. Is executed. Therefore, the time until each extrusion volume reaches the target value, that is, the time until the gear ratio reaches the target value is shortened, and the speed change according to the request becomes possible.

  According to the invention of any one of claims 3 to 5, when each extrusion volume is changed, each extrusion volume is changed so that the ratio of the amount of change coincides with the ratio of each extrusion volume. Therefore, since the torque that is handled by each power transmission path is maintained substantially constant, the transmission mode can be switched without changing the transmission ratio. For this reason, from the state in which each extrusion volume is an intermediate value between the maximum and the minimum with each extrusion volume being changed together, one extrusion volume is fixed at a predetermined value such as the maximum value and the other extrusion volume is When switching to the first speed change mode in which the volume is set to an intermediate value and the transmission ratio is set, each extrusion volume is changed so that the ratio of the change amount of each extrusion volume matches the ratio of each extrusion volume. . Therefore, since the torque that is handled by each power transmission path is maintained substantially constant, the transmission mode can be switched without changing the transmission ratio. Further, since the fluid pressure is relatively low in the set first speed change mode, it is possible to suppress or prevent power loss and deterioration of fuel consumption.

  According to the invention of claim 6, when each of the extrusion volumes is controlled to an intermediate value between the maximum value and the minimum value and the predetermined speed ratio is set, the extrusion volume that minimizes the amount of change from the current extrusion volume. Is selected. That is, there are many combinations of extrusion volumes that set a predetermined transmission gear ratio, and an extrusion volume that minimizes the amount of change in extrusion volume is selected. Therefore, when switching from the state in which the gear ratio is set in the first gear mode to the state in which the gear ratio is set in the second gear mode, the time required for changes in the extrusion volume and gear ratio is shortened. Can be improved. Further, since the flow amount of the pressure fluid is small and the pressure fluctuation can be suppressed, the transmission mode can be switched without causing any change in the transmission ratio or the change in the driving force.

  According to the seventh aspect of the invention, in addition to the functions and effects described above, the variable displacement fluid pressure pump motor functions to generate a reaction force against the differential mechanism, so that torque is transmitted from the power source to the output member. In this case, the torque applied to the variable displacement fluid pressure pump motor becomes relatively small, and therefore the variable displacement fluid pressure pump motor can be reduced in size.

  Next, the present invention will be described based on specific examples. First, the transmission targeted in the present invention will be described. The transmission targeted in the present invention includes at least two power transmission paths, and both of the power transmission paths are used to output members from the power source. Thus, the transmission can continuously change the speed ratio, which is the ratio of the rotational speeds of the power source and the output member. More specifically, each power transmission path includes a variable displacement fluid pressure pump motor that functions as a pump and a motor, respectively, and is configured to transmit torque according to the extrusion volume. The variable displacement fluid pressure pump motor is communicated with each other so as to exchange pressure fluid with each other. Therefore, when one of the variable displacement fluid pressure pump motors functions as a pump, torque corresponding to the extrusion volume is transmitted from the power source to the output member, and at the same time, from one variable displacement fluid pressure pump motor to the other. Pressure fluid is supplied to the variable displacement fluid pressure pump motor, and the other variable displacement fluid pressure pump motor functions as a motor. That is, power transmission via the pressure fluid is performed in parallel. The torque is transmitted to the output member via the other power transmission path. As a result, the torque transmitted to the output member is the sum of the torque transmitted through each power transmission path, and the torque transmitted through the pressure fluid changes according to each extrusion volume. Eventually, the gear ratio changes continuously.

  Each power transmission path can be provided with a transmission mechanism such as a gear pair or a winding transmission mechanism with different speed ratios, and when transmitting torque to the output member via only one power transmission path, the transmission The overall gear ratio is determined by the gear ratio of the transmission mechanism in the power transmission path. If such a gear ratio is referred to as a fixed gear ratio, transmission of power via pressure fluid does not occur in a state where the fixed gear ratio is set. It becomes. In order to allow only one of the transmission mechanisms to participate in torque transmission, it is preferable to include a switching mechanism such as a clutch mechanism in each transmission mechanism, or between the power source or output member and the transmission mechanism. It is preferable to provide a switching mechanism.

  Since the transmission targeted by this invention is configured to transmit power via pressure fluid, it may be a transmission configured as a hydrostatic transmission (HST). It is preferable to be configured as a hydrostatic mechanical transmission (HMT) having a function of setting a transmission gear ratio by dynamic power transmission. The mechanical transmission portion can be appropriately configured as necessary, and a mechanism configured to select a gear pair that is always meshed by a clutch mechanism or a synchronous coupling mechanism, or a plurality of planetary gear mechanisms or compound planetary gears. A configuration in which a plurality of gear ratios can be set by a mechanism can be employed. Further, the variable displacement fluid pressure pump motor may be configured to use a variable displacement fluid pressure pump motor as the reaction force means, in addition to the structure in which the variable displacement fluid pressure pump motor is interposed in series between the power source and the output member.

  Next, the configuration of the transmission targeted by the present invention will be described based on a specific example. The example shown in FIG. 9 is an example configured as a transmission for a vehicle, and uses a differential mechanism as a power distribution mechanism and a plurality of gear pairs as a transmission mechanism, and thus a variable displacement fluid pressure pump motor. Is an example in which four forward speeds and one reverse speed are set as a so-called fixed transmission ratio that can be set by transmitting torque without passing through a fluid. That is, in FIG. 9, an input member 2 is connected to a power source (E / G) 1, and the first planetary gear mechanism 3 and the second planetary gear mechanism corresponding to the differential mechanism in the present invention from the input member 2. 4 is configured to transmit torque.

  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 of these. Further, an appropriate transmission means such as a damper, a clutch, or a torque converter may be interposed between the power source 1 and the input member 2.

  The first planetary gear mechanism 3 is disposed on the same axis as the input member 2, and the second planetary gear mechanism 4 is separated outward in the radial direction of the first planetary gear mechanism 3, and the respective central axes are parallel to each other. Are arranged in parallel. These planetary gear mechanisms 3 and 4 can use planetary gear mechanisms of an appropriate type such as a single pinion type and a double pinion type. The example shown in FIG. 9 is an example constituted by a single-pinion type planetary gear mechanism, and sun gears 3S and 4S that are external gears, and a ring gear 3R that is an internal gear arranged concentrically with the sun gears 3S and 4S. , 4R and carriers 3C, 4C holding pinion gears meshed with these sun gears 3S, 4S and ring gears 3R, 4R so as to be rotatable and revolved. The input member 2 is connected to a ring gear 3R in the first planetary gear mechanism 3, and the ring gear 3R serves as an input element.

  Further, a counter drive gear 5 is attached to the input member 2, and an idle gear 6 is engaged with the counter drive gear 5, and a counter driven gear 7 is engaged with the idle gear 6. The counter driven gear 7 is disposed on the same axis as the second planetary gear mechanism 4 and is connected to the ring gear 4R of the second planetary gear mechanism 4 so as to rotate together. Therefore, in the second planetary gear mechanism 4, the ring gear 4R serves as an input element. The ring gears 3R and 4R, which are input elements of the planetary gear mechanisms 3 and 4, are configured so that the counter gear pair includes the idle gear 6, and thus rotate in the same direction.

  The carrier 3C in the first planetary gear mechanism 3 serves as an output element, and the first intermediate shaft 8 is connected to the carrier 3C so as to rotate integrally. The first intermediate shaft 8 is a hollow shaft into which a motor shaft 9 is rotatably inserted. One end of the motor shaft 9 is a sun gear that is a reaction force element in the first planetary gear mechanism 3. It is connected to 3S so as to rotate together.

  The second planetary gear mechanism 4 has the same configuration, and the carrier 4C serves as an output element, and the second intermediate shaft 10 is connected to the carrier 4C so as to rotate together. The second intermediate shaft 10 is a hollow shaft into which a motor shaft 11 is rotatably inserted. One end of the motor shaft 11 is a sun gear that is a reaction force element in the second planetary gear mechanism 4. 4S is connected to rotate integrally.

  The other end of the motor shaft 9 is connected to the output shaft of the variable displacement pump motor 12. The variable displacement pump motor 12 is a fluid pressure (hydraulic) pump capable of changing the discharge capacity, such as a slant shaft pump, a swash plate pump, or a radial piston pump, and is rotated by applying torque to its output shaft. It functions as a motor by discharging pressure fluid (pressure oil) by functioning as a pump and supplying pressure fluid from a discharge port or suction port. In the following description, the variable displacement pump motor 12 is referred to as a first pump motor 12 and is represented as PM1 in the drawing.

  The other end of the motor shaft 11 is connected to the output shaft of the variable displacement pump motor 13. The variable displacement pump motor 13 has the same configuration as the first pump motor 12 on the motor shaft 9 side, and therefore, a fluid capable of changing the discharge capacity, such as an oblique shaft pump, a swash plate pump, or a radial piston pump. A pressure (hydraulic) pump can be employed. In the following description, the variable displacement pump motor 13 is referred to as a second pump motor 13 and is indicated as PM2 in the figure.

  The pump motors 12 and 13 are communicated with each other by oil passages 14 and 15 so that the pressure oil, which is a pressure fluid, can be transferred to each other. That is, the suction ports 12S and 13S are communicated with each other by the oil passage 14, and the discharge ports 12D and 13D are communicated with each other through the oil passage 15. Accordingly, a closed circuit is formed by the oil passages 14 and 15. A mechanism for controlling the hydraulic pressure in the closed circuit will be described later.

  An output shaft 16 corresponding to the output member of the present invention is arranged in parallel with each of the intermediate shafts 8 and 10 described above. A transmission mechanism for setting a predetermined gear ratio is provided between the output shaft 16 and each of the intermediate shafts 8 and 10. The transmission mechanism in the present invention is not limited to a mechanism that transmits power at a fixed rotation speed ratio (transmission ratio), and a mechanism with a variable transmission ratio can be employed. In the example shown in FIG. A plurality of gear pairs 17, 18, 19, and 20 that transmit power at different gear ratios are employed.

  More specifically, the first intermediate shaft 8 has a fourth speed drive gear 17A of the fourth speed gear pair 17 and a second speed drive of the second speed gear pair 18 in order from the first planetary gear mechanism 3 side. A gear 18A is disposed, and the fourth speed driving gear 17A and the second speed driving gear 18A are rotatably fitted to the first intermediate shaft 8. The fourth speed driven gear 17B of the fourth speed gear pair 17 meshed with the fourth speed drive gear 17A, and the second speed driven gear 18B of the second speed gear pair 18 meshed with the second speed drive gear 18A Is attached to the output shaft 16 so as to rotate integrally therewith.

  Further, the third speed drive gear 19A of the third speed gear pair 19 that meshes with the fourth speed driven gear 17B and the first speed drive of the first speed gear pair 20 that meshes with the second speed driven gear 18B. A gear 20 </ b> A is rotatably fitted to the second intermediate shaft 10. Accordingly, the fourth speed driven gear 17B also serves as the third speed driven gear of the third speed gear pair 19, and the second speed driven gear 18B also serves as the first speed driven gear of the first speed gear pair 20. . Here, the rotational speed ratio or gear ratio of each gear pair 17, 18, 19, 20 (ratio of the number of teeth of the driven gear to the number of teeth of each drive gear) will be described. The gear pair 20 for the second gear, the gear pair 18 for the second speed, the gear pair 19 for the third speed, and the gear pair 17 for the fourth speed are configured to become smaller in this order.

  Furthermore, a starting gear pair 21 is provided. The starting gear pair 21 is used to transmit the power to the output shaft 16 together with the first speed gear pair 20 so that the driving force at the time of starting is sufficiently large. A start drive gear 21A attached to the motor shaft 9 on the pump motor 12 side and a start driven gear 21B attached to the output shaft 16 so as to be rotatable are provided.

  A clutch mechanism is provided for allowing each of the gear pairs 17, 18, 19, 20, and 21 described above to transmit torque between any of the intermediate shafts 8 and 10 and the output shaft 16. In short, this clutch mechanism is a mechanism for selectively transmitting torque, and a conventionally known mechanism such as a dog clutch mechanism or a synchronous coupling mechanism (synchronizer) can be adopted. An example of adopting a Nizer is shown.

  The synchronizer basically has a sleeve that rotates together with a rotating shaft, a spline provided on another rotating member that rotates relative to the rotating shaft, and is moved by the sleeve toward the other rotating member. And synchronizer ring. Then, in the process of moving the sleeve to the spline side of the other rotating member, the synchronizer ring gradually makes frictional contact with the rotating member to synchronize the rotating shaft and the rotating member, and in that state the sleeve engages with the spline. Thus, the rotating shaft and the rotating member are connected to each other. On the output shaft 16, a first synchronizer (hereinafter referred to as a first synchronizer) 22 is provided at a position adjacent to the starter driven gear 21B. The first sync 22 moves its sleeve to the left side of FIG. 9 to connect the starter driven gear 21B to the output shaft 16, and the starter gear pair 21 torques between the motor shaft 9 and the output shaft 16. Is configured to communicate.

  On the second intermediate shaft 10, a second synchronizer (hereinafter referred to as a second synchronizer) 23 is provided between the third speed drive gear 19A and the first speed drive gear 20A. The second sync 23 moves the sleeve to the left side of FIG. 9 to connect the first speed drive gear 20A to the second intermediate shaft 10, and the first speed gear pair 20 is connected to the second intermediate shaft 10. Torque is transmitted to and from the output shaft 16. On the other hand, the third speed drive gear 19A is connected to the second intermediate shaft 10 by moving the sleeve to the right in FIG. 9, and the third speed gear pair 19 is connected to the second intermediate shaft 10 and the output shaft 16. Torque is transmitted between the two.

  Further, on the first intermediate shaft 8, a third synchronizer (hereinafter referred to as a third synchronizer) 24 is provided between the second speed drive gear 18A and the fourth speed drive gear 17A. The third synchronizer 24 moves the sleeve to the left side in FIG. 9 to connect the second speed drive gear 18A to the first intermediate shaft 8, and the second speed gear pair 18 is connected to the first intermediate shaft 8. Torque is transmitted to and from the output shaft 16. On the other hand, the fourth speed drive gear 17A is connected to the first intermediate shaft 8 by moving the sleeve to the right in FIG. 9, and the fourth speed gear pair 17 is connected to the first intermediate shaft 8 and the output shaft 16. Torque is transmitted between the two.

  Furthermore, a reverse synchronizer (hereinafter referred to as “R synchro”) 25 is provided on the motor shaft 11 on the second pump motor 13 side at a position adjacent to the shaft end of the second intermediate shaft 10. The R synchro 25 connects the motor shaft 11 and the second intermediate shaft 10, that is, the sun gear 4S and the carrier 4C in the second planetary gear mechanism 4 by moving the sleeve to the right in FIG. The entire planetary gear mechanism 4 is configured to rotate integrally.

  Each of the synchros 22, 23, 24, and 25 can be configured to be switched by manual operation, but can be configured to perform so-called automatic control instead. In that case, for example, an appropriate actuator (not shown) for moving the above-described sleeve in the axial direction may be provided, and the actuator may be electrically controlled.

  As described above, the transmission shown in FIG. 9 is configured such that the torque output from the power source 1 is transmitted to the output shaft 16 via any one of the intermediate shafts 8 and 10 or the motor shafts 9 and 11. ing. A differential 27 is connected to the output shaft 16 through a transmission means 26 such as a gear mechanism or a winding transmission mechanism such as a chain, and power is output to the left and right axles 28 from here.

  Furthermore, a sensor for detecting the operating state of the transmission is provided. Specifically, the input rotational speed sensor 29 for detecting the rotational speed Nin of the input member 2 or the counter drive gear 5 integrated therewith, the output rotational speed sensor 30 for detecting the rotational speed Nout of the axle 28, the first A rotation speed sensor 31 for detecting the rotation speed NPM1 of the pump motor 12 and a rotation speed sensor 32 for detecting the rotation speed NPM2 of the second pump motor 13 are provided.

  Next, a fluid pressure circuit (hydraulic circuit) for controlling the pump motors 12 and 13 will be described. The closed circuits 14 and 15 communicating with the pump motors 12 and 13 are provided with charge pumps (sometimes referred to as boost pumps) 33 for supplying fluid (specifically oil). Yes. The charge pump 33 is used to compensate for the shortage of oil due to leakage from the closed circuit, and is driven by the power source 1 or a motor (not shown) to pump oil from the oil pan 34. It is designed to supply a closed circuit.

  The discharge port of the charge pump 33 communicates with the oil passage 14 and the oil passage 15 in the closed circuit via check valves 35 and 36, respectively. In addition, these check valves 35 and 36 are comprised so that it may open in the discharge direction from the charge pump 33, and may close in the opposite direction. Further, a relief valve 37 for adjusting the discharge pressure of the charge pump 33 is communicated with the discharge port of the charge pump 33. The relief valve 37 is configured to open and discharge oil to the oil pan 34 when a pressure higher than the sum of the elastic force of the spring and the pressure of the pilot pressure or the solenoid is applied. The discharge pressure is set to a pressure corresponding to the pilot pressure.

  Further, a relief valve 38 is provided between the suction port 12 </ b> S of the first pump motor 12 and the oil passage 15. In other words, the relief valve 38 is provided in parallel with the first pump motor 12 so as to communicate the oil passages 14 and 15. The relief valve 38 is configured to maintain the discharge pressure at a preset pressure when pressure oil is discharged from the suction port 12S of the first pump motor 12 or the suction port 13S of the second pump motor 13. ing. A relief valve 39 is provided between the discharge port 13 </ b> D of the second pump motor 13 and the oil passage 14. In other words, the relief valve 39 is provided in parallel with the second pump motor 13 so as to communicate the oil passages 14 and 15. The relief valve 39 is configured to maintain the discharge pressure at a preset pressure when pressure oil is discharged from the discharge port 13D of the second pump motor 13 or the discharge port 12D of the first pump motor 12. ing.

  The pump volume of each of the pump motors 12, 13 and the synchros 22, 23, 24, 25 are configured to be electrically controlled, and an electronic control unit (ECU) 40 is provided for that purpose. The electronic control unit 40 is mainly composed of a microcomputer, and is inputted with the number of rotations of a predetermined rotating member and other detection signals, and the inputted signals and information stored in advance. In addition, the calculation is performed based on the program, and the command signal is output according to the calculation result.

  Next, the operation of the transmission described above will be described. FIG. 10 is a chart collectively showing the operation states of the pump motors (PM1, PM2) 12, 13 and the synchros 22, 23, 24, 25 when setting the respective gear positions. “OFF” for each of the pump motors 12 and 13 makes the pump capacity substantially zero, does not generate pressure oil even if the output shaft is rotated, and the output shaft is not supplied even if hydraulic pressure is supplied. A state where the rotor does not rotate (free) is indicated, and “LOCK” indicates a state where the rotation of the rotor is stopped. Furthermore, “hydraulic pressure generation” indicates a state in which the pump capacity is made larger than substantially zero and pressure oil is discharged, and thus the corresponding pump motors 12 and 13 function as pumps. “Hydraulic pressure recovery” indicates a state in which pressure oil discharged from one pump motor 13 (or 12) is supplied to function as a motor, and therefore the corresponding pump motor 12 (or 13) has a shaft torque. The generated torque is transmitted to the corresponding motor shafts 9 and 11 and the intermediate shafts 8 and 10.

  Further, “right” and “left” for each of the synchros 22, 23, 24, and 25 indicate the positions of the sleeves in the respective synchros 22, 23, 24, and 25 in FIG. 9, and the parentheses are downshifted. The stand-by state, the brackets indicate the stand-by state for upshifting, and “◯” reduces drag by setting the corresponding synchro 22, 23, 24, 25 to the OFF state (neutral position). “●” indicates that the corresponding synchro 22, 23, 24, 25 is set to the OFF state (neutral position) and is in the neutral state.

  When the neutral position is selected and the neutral (N) state is set, the pump motors 12 and 13 are set to the “OFF” state, and the sleeves of the synchros 22, 23, 24, and 25 are set to the center positions. The Therefore, none of the gear pairs 17, 18, 19, 20, 21 is in a neutral state that is not connected to the output shaft 16. That is, the pump motors 12 and 13 are controlled so that their extrusion volumes (pump capacity) are substantially zero. As a result, a so-called idling state is established, so that even if torque is transmitted from the power source 1 to the ring gears 3R, 4R of the planetary gear mechanisms 3, 4, no reaction force acts on the sun gears 3S, 4S. Therefore, torque is not transmitted to the intermediate shafts 8 and 10 connected to the carriers 3C and 4C that are output elements.

  When the shift position is switched to a travel position such as a drive position, the sleeve of the first sync 22 is moved to the left in FIG. 9 and the sleeve of the second sync 23 is moved to the left in FIG. Therefore, the starting drive gear 21A is connected to the motor shaft 9, the first pump motor 12 and the output shaft 16 are connected, and the first speed drive gear 20A is connected to the second intermediate shaft 10 to be the second planetary gear mechanism. 4 is the output element 4 and the output shaft 16 is coupled. That is, the first speed that is the fixed gear ratio is set. At the same time, the extrusion volume of each pump motor 12, 13 is controlled to be larger than zero.

  Therefore, the second pump motor 13 is driven by the power of the power source 1 distributed by the second planetary gear mechanism 4 and functions as a pump. Therefore, the second pump motor 13 gives reaction force torque accompanying generation of hydraulic pressure to the motor shaft 11 and the sun gear 4S. This is described as “hydraulic pressure generation” in FIG. Therefore, the torque is transmitted to the carrier 4C by the differential action of the second planetary gear mechanism 4, and the torque is transmitted to the output shaft 16 via the first speed gear pair 20.

  On the other hand, the hydraulic pressure generated by the second pump motor 13 is discharged from the suction port 13S and supplied to the suction port 12S of the first pump motor 12. As a result, the first pump motor 12 functions as a motor. This is described as “hydraulic pressure recovery” in FIG. In this way, the power transmitted to the first pump motor 12 is transmitted to the output shaft 16 via the starting gear pair 21. Therefore, in the driving state from the start to the first speed, both so-called mechanical power transmission via the second planetary gear mechanism 4 and power transmission via the hydraulic pressure are generated, and the combined power of these powers is generated. Appears on the output shaft 16. Further, the gear ratio in this process becomes a value larger than the first speed which is a fixed gear ratio, and the gear ratio changes continuously or steplessly.

  Thus, when the rotational speed and the vehicle speed of the power source 1 change to the first speed gear ratio, the extrusion volume q1 of the first pump motor 12 is set to zero, and the extrusion volume q2 of the second pump motor 13 is maximized. As a result, the rotation of the second pump motor 13 is substantially locked. That is, the motor shaft 11 and the second pump motor 13 connected thereto are fixed. At the same time, the first sync 22 is set to the OFF state. As a result, the sun gear 4S of the second planetary gear mechanism 4 is fixed, and the first planetary gear mechanism 3 is not involved in the transmission of power to the output shaft 16, so that the power output from the power source 1 is the second planetary gear. It is transmitted to the output shaft 16 via the mechanism 4 and the first speed gear pair 20. That is, a fixed gear ratio determined by the gear ratio of the first speed gear pair 20 is set. In this case, since the first pump motor 12 and the motor shaft 9 connected thereto are idled, no torque appears on the first intermediate shaft 8.

  When upshifting from the first speed, which is the fixed gear ratio, the sleeve of the third sync 24 is moved to the left in FIG. 9 to connect the second speed drive gear 18A to the first intermediate shaft 8. The R synchro 25 is kept in a neutral state. Further, when the sleeve of the third synchro 24 is engaged with the second speed drive gear 18A, synchronous control is performed so that the rotation speed of the sleeve of the third synchro 24 matches the rotation speed of the second speed drive gear 18A. The synchronization control is performed in the same manner when the sleeves of the synchros 22, 23, 24, and 25 are engaged with the mating members.

  In this state, the extrusion volume q1 of the first pump motor 12 is gradually increased toward the maximum. In the upshift standby state to the second speed, the first pump motor 12 rotates in the reverse direction, and thus functions as a pump by gradually increasing the extrusion volume q1. That is, the hydraulic pressure is generated (indicated as “hydraulic pressure generation” in FIG. 10), and at the same time, the reaction torque generated thereby appears on the motor shaft 9. As a result, transmission of power through the first planetary gear mechanism 3 and the second speed gear pair 18 is gradually performed. Further, the hydraulic pressure generated by the first pump motor 12 is supplied to the second pump motor 13 and functions as a motor (denoted as “hydraulic pressure recovery” in FIG. 10), so the second pump motor 13 and the second planetary gear. Power is transmitted through the gear mechanism 4 and the first speed gear pair 20. Therefore, the speed ratio in the process of shifting from the first speed to the second speed is a value between the speed ratio of the first speed and the speed ratio of the second speed and is a continuously changing speed ratio. . That is, a continuously variable transmission state in which the gear ratio continuously changes is obtained. This is the same during the period from the start to the speed ratio of the first speed and between the fixed speed ratios. Therefore, the above-described transmission can function as a continuously variable transmission.

  In a state where the first speed which is a fixed gear ratio is set, the extrusion volume q1 of the first pump motor 12 is set to zero (or less than a predetermined value close to the minimum), and the extrusion volume q2 of the second pump motor 13 is set. Is greater than or equal to a predetermined value that is at or near the maximum. Accordingly, the first pump motor 12 and the motor shaft 9 connected to the first pump motor 12 run idle, and the pressure oil cannot flow from the second pump motor 13 to the first pump motor 12. Therefore, the second pump motor 13 becomes locked. From this state, the extrusion volume q1 of the first pump motor 12 is first gradually increased. As a result, hydraulic pressure is generated in the first pump motor 12, and this is supplied to the second pump motor 13, so that the second pump motor 13 acts as a motor. That is, power is transmitted between the pump motors 12 and 13 via the pressure oil.

  Thus, when the extrusion volume q1 of the first pump motor 12 is maximized, the extrusion volumes q1 and q2 of the pump motors 12 and 13 are both maximized or more than a predetermined value close to this. Thereafter, the extrusion volume q2 of the second pump motor 13 is gradually reduced while maintaining the extrusion volume q1 of the first pump motor 12 at a maximum or close to a predetermined value close to this. And the 2nd speed which is a fixed gear ratio is set when the extrusion volume q2 of the 2nd pump motor 13 becomes zero (or below predetermined value near minimum). That is, power is transmitted only through the second speed gear pair 18 of each gear pair, and a gear ratio according to the rotation speed ratio of the second speed gear pair 18 is set.

  When the extrusion volume q1 of the first pump motor 12 is substantially maximized and its rotation is stopped or is almost stopped, the motor shaft 9 is substantially fixed. In addition, the second pump motor 13 is set to the OFF state. Therefore, in the first planetary gear mechanism 3, since the sun gear 3S is fixed, the power input to the ring gear 3R is output from the carrier 3C to the second speed drive gear 18A via the intermediate shaft 8. On the other hand, the second pump motor 13 is in the OFF state, and the R synchro 25 and the second synchro 23 arranged coaxially with the second pump motor 13 are in the OFF state and the sleeve is in the neutral position. The motor 13 and the second planetary gear mechanism 4 are not involved in power transmission. Accordingly, the second speed, which is a fixed gear ratio determined by the gear ratio of the second speed gear pair 18, is set.

  Similarly, in the third speed, the sleeve of the second synchro 23 is moved to the right side in FIG. 9 to connect the third speed drive gear 19A to the second intermediate shaft 10, and the extrusion volume of the second pump motor 13 is also increased. By maximizing q2, as in the case of the first speed, the motor shaft 11 and the second pump motor 13 are fixed, and the other synchros 22 and 24 are set to the OFF state. Accordingly, the power is transmitted to the output shaft 16 via the third speed gear pair 19, and the third speed, which is a fixed gear ratio, is set. For the fourth speed, the sleeve of the third synchro 24 is moved to the right in FIG. 9 to connect the fourth speed drive gear 17A to the first intermediate shaft 8, and the extrusion volume q1 of the first pump motor 12 is maximized. As a result, as in the case of the second speed, the motor shaft 9 and the first pump motor 12 are fixed, and the other synchros 23 and 25 are set to the OFF state. Therefore, power is transmitted to the output shaft 16 via the fourth speed gear pair 17 and the fourth speed, which is a fixed gear ratio, is set.

  Further, the reverse gear will be described. When the reverse position is selected, the sleeve of the first sync 22 is moved to the left side of FIG. 9, and the sleeve of the R sync 25 is moved to the right side of FIG. Further, the other syncs 23 and 24 are set to the OFF state. Therefore, when the second intermediate shaft 10 and the motor shaft 11 are connected by the R synchro 25, the sun gear 4S of the second planetary gear mechanism 4 and the carrier 4C are connected, and the entire second planetary gear mechanism 4 is substantially the same. Integrated. The start drive gear 21 </ b> A is connected to the motor shaft 9, that is, the rotor of the first pump motor 12.

  Therefore, the power transmitted from the power source 1 to the second planetary gear mechanism 4 is transmitted to the second pump motor 13 as it is, and this is driven, and the second pump motor 13 generates hydraulic pressure. Since the second synchro 23 is in the OFF state, power is not transmitted from the second planetary gear mechanism 4 or the second intermediate shaft 10 to the output shaft 16. On the other hand, the extrusion volume q1 of the first pump motor 12 is controlled to a volume larger than zero, for example, the maximum volume. As a result, the first pump motor 12 functions as a motor by the hydraulic pressure supplied from the second pump motor 13 and outputs torque to the motor shaft 9. In that case, since the hydraulic pressure is supplied to the first pump motor 12 from the discharge port 12D, the first pump motor 12 rotates in the reverse direction. Then, the torque is transmitted to the output shaft 16 via the starting gear pair 21, so that a reverse state is established. That is, in the reverse gear, power is transmitted via the hydraulic pressure, and in FIG. 10, this is indicated as “hydraulic pressure recovery” for the first pump motor 12 and “hydraulic pressure generation” for the second pump motor 13.

  When shifting by the transmission configured as described above is performed, the extrusion volumes q1 and q2 of the pump motors 12 and 13 are increased or decreased. As the increase / decrease control of the extrusion volumes q1, q2 of the pump motors 12, 13, so-called sequential control and simultaneous control are possible.

  The sequential control refers to the control of the other pump motor 13 (or 12) after the change of the extrusion volume q1 (or q2) of one pump motor 12 (or 13) of the two pump motors involved in the shift is completed. It is the control of the form to perform. In other words, the transmission ratio is set by changing the extrusion volume q2 (or q1) of the other pump motor 13 (or 12) while the extrusion volume q1 (or q2) of one pump motor 12 (or 13) is fixed. This is a shift control executed in the first shift mode of the present invention. In the case of the shift control (sequential control) in the first shift mode, the discharge pressure of each pump motor 12, 13 or the pressure in the hydraulic circuit can be lowered in the shift transient state between the fixed stages. Power loss associated with operating the pump motors 12 and 13 can be reduced, and the fuel efficiency of the vehicle can be improved. Further, since the pump motors 12 and 13 that are involved in the shift need only be controlled in order, the shift control is facilitated.

  On the other hand, the simultaneous control is a control in which the shift is executed by simultaneously changing the extrusion volumes q1 and q2 of the two pump motors 12 and 13 involved in the shift in opposite directions. In other words, it is control for setting the gear ratio by changing the extrusion volumes q1, q2 of the pump motors 12, 13 simultaneously and in opposite directions, and is the gear shift control executed in the second gear shift mode of the present invention. . In the case of the shift control (simultaneous control) in the second shift mode, since the discharge pressures of the pump motors 12 and 13 hardly change, it becomes easy to stabilize the shift control. In addition, since the extrusion volumes q1 and q2 of the pump motors 12 and 13 are simultaneously changed, the time required for the shift is shortened, so that the shift response can be improved.

  The speed change control for setting the speed ratio in the first speed change mode or the second speed change mode as described above is executed by, for example, the electronic control device 40 described above, and therefore the electronic control device 40 corresponds to the speed change control means of the present invention. .

Further, the gear ratio set by the transmission configured as described above can be expressed by the following relational expression. That is, the extrusion volume of the first pump motor 12 is q1, the extrusion volume of the second pump motor 13 is q2, and the number of teeth of the gear pair that transmits power between the carrier 3C of the first planetary gear mechanism 3 and the output shaft 16. If the ratio is κ1 and the gear ratio of the gear pair transmitting power between the carrier 4C of the second planetary gear mechanism 4 and the output shaft 16 is κ2, the gear ratio γ is given by
γ = (κ1 × q1 + κ2 × q2) / (q1 + q2) (1)
Can be expressed as

Based on the relationship expressed by the above equation (1), the change amounts of the extrusion volumes q1 and q2 of the pump motors 12 and 13 are Δq1 and Δq2, respectively, and the extrusion volumes q1 and q of the pump motors 12 and 13 are set. q2
Δq1: Δq2 = q1: q2 (2)
The speed ratio γ as a steady characteristic can be kept constant by changing based on the relationship expressed by

  As described above, the transmission control device according to the present invention can perform control for setting the transmission ratio in the first transmission mode and control for setting the transmission ratio in the second transmission mode. When switching from the state where the gear ratio is set in the mode to the state where the gear ratio is set in the second gear mode, or from the state where the gear ratio is set in the second gear mode, the gear ratio is changed in the first gear mode. When switching to the state where the vehicle is set, if a response delay or switching shock occurs in the switching operation, there is a possibility that the occupant may feel uncomfortable. Therefore, in the transmission control apparatus of the present invention, the extrusion volumes q1 and q2 of the pump motors 12 and 13 are controlled as the third speed change mode using the relationship expressed by the above equations (1) and (2). Specifically, by setting the transmission gear ratio by changing the extrusion volumes q1 and q2 of the pump motors 12 and 13 simultaneously and in the same direction, the response delay of the switching operation when switching the transmission mode. And the control to avoid or suppress the occurrence of the switching shock. An example of the control will be described below.

(First control example)
FIG. 1 is a flowchart for explaining a first control example in the control device of the present invention. The routine shown in this flowchart is repeatedly executed every predetermined short time. In FIG. 1, first, as an initial state, it is confirmed whether the current shift mode is the first shift mode, the second shift mode, or the third shift mode (step S11). In the following description and flowchart, it is assumed that the first shift mode is referred to as shift A, the second shift mode is referred to as shift B, and the third shift mode is referred to as shift C.

  Subsequently, it is determined whether or not there is a request for sudden shift (step S12). This determination can be made based on, for example, the amount of change from the previous value of the target speed ratio obtained by external processing different from this routine or a value obtained by filtering the amount of change. . For example, when the amount of change from the previous value of the target gear ratio is greater than a predetermined value, it is determined that the current shift is a sudden shift. It is also possible to detect the depression amount and the depression speed of the accelerator pedal by the occupant, or detect a manual shift by the occupant, and determine whether or not the current shift is an abrupt shift based on the detected values.

  If the current shift is an abrupt shift, and if the determination in step S12 is affirmative, it is necessary to improve the shift response in order to execute the abrupt shift. B, that is, the second speed change mode is set. If the gear shift B has been set from the beginning, the setting is maintained as it is, and if another gear shift mode has been set, the gear shift B is switched and set. In the control at the shift B, for example, from the map as shown in FIG. 3, the extrusion volumes q1 and q2 of the pump motors 12 and 13 corresponding to the target gear ratio are obtained, and the shift B based on these extrusion volumes q1 and q2 is obtained. The shift control at is performed. Then, this routine is once ended.

  On the other hand, if the current shift is not a sudden shift and a negative determination is made in step S12, the process proceeds to step S14 to determine whether or not the current shift mode is the shift A. . As described above, in the shift A, that is, in the first shift mode, the discharge pressures of the pump motors 12 and 13 can be made lower than in the shift B. Therefore, in a normal state where there is no request for sudden shift or change of the shift mode. By setting the transmission A, the fuel consumption of the vehicle can be improved. Therefore, if the current speed change mode is set to speed change A, and an affirmative determination is made in step S14, the process proceeds to step S15 and the setting of speed change A is maintained as it is. Then, this routine is once ended.

  On the other hand, if the current shift mode is not shift A, and a negative determination is made in step S14, the process proceeds to step S16, where the shift mode is set to the shift C, that is, the third shift mode. When the current shift mode is set to other than the shift A, the efficiency can be improved by setting the shift mode to the shift A. Therefore, the shift mode is set to the shift C and the shift mode is set to the shift A. The control to switch quickly and smoothly is executed.

The details of the control in the case of the shift C in the step S16, that is, the control in the third shift mode, that is, the control content when the shift mode is switched from the shift B to the shift A are shown in the flowchart of FIG. In FIG. 2, similarly to the control in the shift B in step S13 described above, the extrusion volumes q1 and q2 of the pump motors 12 and 13 corresponding to the target gear ratio are obtained from a map as shown in FIG. Step S16-1). Subsequently, the change amounts Δq1, Δq2 of the extrusion volumes of the pump motors 12, 13 satisfying the above-described equation (2) are determined, and the temporary output extrusion volumes q′1, q′2 are calculated. That is, the temporary output extrusion volume q′1, q′2 is
q'1 = q1 + Δq1 (3)
q'2 = q2 + Δq2 (4)
(Step S16-2).

  Here, one of the change amounts Δq1 and Δq2 of the extrusion volume is set as a constant within a range in which the speed ratio γ is not changed, and the other is set to the provisional output extrusion volume q so as to satisfy the above expressions (3) and (4). '1, q'2 is calculated. At that time, if “extrusion volume q1> extrusion volume q2”, the change amount Δq1 of the extrusion volume is determined as a constant, and if “extrusion volume q1 <extrusion volume q2”, the change amount Δq2 of the extrusion volume is determined as a constant. As a result, one of the change amounts is always less than a constant, so that fluctuations in the gear ratio γ can be suppressed.

  When the temporary output extrusion volumes q′1 and q′2 are calculated, one of the temporary output extrusion volumes q′1 and q′2 is the maximum value qmax of the extrusion volume of each pump motor 12 or 13. Is determined (step S16-3). If neither of these temporary output push-out volumes q′1 and q′2 has reached the maximum value qmax, and if a negative determination is made in step S16-3, the process proceeds to step S16-4 and this speed change is made. The shift control by C is continued. That is, the temporary output extrusion volumes q′1 and q′2 obtained in step S16-2 are set to the extrusion volumes q1 and q2 as final outputs, and the shift control is executed based on the extrusion volumes q1 and q2 ( Continued).

  On the other hand, if any one of the temporary output extrusion volumes q′1 and q′2 has reached the maximum value qmax and the determination is affirmative in step S16-3, the process proceeds to step S16-5. Then, the shift control by the shift A is executed. That is, when one of the temporary output extrusion volumes q′1 and q′2 reaches the maximum value qmax, it can be determined that the shift mode at that time has completed the shift to the shift A. For example, FIG. From the map as shown in FIG. 4, the extrusion volumes q1 and q2 of the pump motors 12 and 13 corresponding to the target gear ratio are obtained, and the shift control at the shift A is executed based on the extrusion volumes q1 and q2. . Then, returning to the flowchart of FIG. 1, this routine is temporarily terminated.

  When the first control example is executed, the gear ratio γ, the extrusion volumes q1 and q2 of the pump motors 12 and 13, the discharge pressures of the pump motors 12 and 13 (closed circuit between the pump motors 12 and 13) The behavior of the hydraulic pressure p) is shown in the time chart of FIG. In the time chart of FIG. 5, the shift control by the shift A is executed in the period before the time t11, the sudden shift is requested at the time t11, and from the time t11 to the time t12 at which the sudden shift request ends. In this period, the shift control by the shift B is executed, the shift control by the shift C is started from the time t12, and the shift to the shift A is completed at the time t13.

  When a sudden shift is performed by the shift B, the discharge pressure p rises while the shift control by the shift B is being executed, but the shift is performed by switching to the control by the shift C from time t12. The shift mode is switched from the shift B to the shift A without changing the speed ratio γ. As a result, it is possible to avoid or suppress the occurrence of a shift shock due to a change in the transmission gear ratio γ or a sense of incongruity to the occupant at the transition of the shift mode from the shift B to the shift A. . Further, since the shift mode is switched from the shift B to the shift A as soon as possible by the control in the shift C, the shift response can be improved, and power loss and deterioration of fuel consumption can be suppressed or prevented.

(Second control example)
Next, a second control example in the control device of the present invention will be described. In the first control example described above, when shifting the shift mode from the shift B to the shift A, the shift control by the shift C is executed to change the shift B to the shift A without causing a change in the gear ratio γ. In contrast to the control example in which the shift mode is shifted, the second control example executes the shift control by the shift C when shifting the shift mode from the shift A to the shift B. Thus, in the control example, the shift mode is shifted from the shift A to the shift B without causing a sudden change in the discharge pressure p of the pump motors 12 and 13.

  FIG. 6 is a flowchart for explaining the second control example. Like the flowchart of FIG. 1, the routine shown in this flowchart is repeatedly executed every predetermined short time. In FIG. 6, first, as an initial state, it is confirmed whether the current shift mode is the first shift mode, the second shift mode, or the third shift mode (step S21).

  Subsequently, it is determined whether or not there is a request for sudden shift (step S22). As in step S12 in the flowchart of FIG. 1 described above, for example, a determination is made based on a change amount of the value from the previous value or a value obtained by filtering the change amount with respect to the target gear ratio obtained by external processing. be able to. Alternatively, it is possible to detect whether or not the current shift is an abrupt shift based on detected amounts of accelerator pedal depression and depression speed by the occupant and manual shift by the occupant.

  If the current shift is not a sudden shift, and a negative determination is made in step S22, the process proceeds to step S23, where it is determined whether the current shift mode is a shift A. Since the control in step S23 and the subsequent steps S24 and S25 is the same as the control in steps S14, S15 and S16 in the first control example described above, detailed description will be given. Omitted.

  On the other hand, if the current shift is an abrupt shift, and if the determination in step S22 is affirmative, the shift response is improved in order to execute the abrupt shift, that is, the shift mode is changed to the shift B, the second To set the shift mode, the process proceeds to step S26. In this step S26, when executing the shift control by the shift B in the shift mode, each of the push-out displacements Δq1 and Δq2 of the pump motors 12 and 13 is minimized so that the larger change amount is minimized. Volume changes Δq 1 and Δq 2 are calculated, and the extrusion volumes q 1 and q 2 of the pump motors 12 and 13 are corrected.

  Details of the control contents calculated by correcting the extrusion volumes q1 and q2 of the pump motors 12 and 13 in step S26 are shown in the flowchart of FIG. In FIG. 7, first, similarly to the control by the shift B in step S13 in the first control example described above, for example, from the map as shown in FIG. The volumes are obtained as extrusion volumes q1new and q2new (step S26-1).

From the extrusion volume q1new, q2new obtained in step S26-1 and the extrusion volume q1old, q2old which is the previous value of the extrusion volume, from the previous value of the extrusion volume of each pump motor 12, 13 according to the target gear ratio. Increase / decrease amounts dq1, dq2 are calculated. That is, the increase / decrease amounts dq1, dq2 are respectively
dq1 = q1new-q1old (5)
dq2 = q2new-q2old (6)
(Step S26-2). These are target values when it is assumed that the extrusion volumes q1 and q2 of the pump motors 12 and 13 are in the state shown in FIG. 3, and are therefore temporary target values for obtaining a final target value. .

Subsequently, the above equation (2), that is, here,
Δq1: Δq2 = q1new: q2new (2 ')
Satisfy the relationship, and
Max {| dq1 + Δq1 |, | dq2 + Δq2 |} (7)
As a value that minimizes the displacement, the changes Δq1, Δq2 in the extrusion volume are calculated (step S26-3).

  As described above, in the transmission targeted by the present invention, when the extrusion volumes of the pump motors 12 and 13 are simultaneously controlled when the shift is executed, both the extrusion volumes q1 and q2 are simultaneously adjusted. There is no change in direction. Further, simultaneously changing both the extruding volumes q1 and q2 in the negative direction may occur at the timing of shifting the shift mode from the shift A to the shift B. In this case, as shown in the equation (7), Since the calculation for correcting the change amounts Δq1, Δq2 of the extrusion volume is a positive addition, the change amount of the extrusion volume is reduced as the addition is added, and finally the extrusion of each pump motor 12, 13 is performed. The direction of volume change results in a state where one is positive and the other is negative. Therefore, in step S26-3, when calculating the change amounts Δq1, Δq2 of the extrusion volume based on the equations (2 ′), (7), the extrusion volumes of the pump motors 12, 13 are controlled simultaneously. The case where one extrusion volume is controlled in the positive direction and the other extrusion volume is controlled in the negative direction may be considered.

When the extrusion volumes of the pump motors 12 and 13 are controlled simultaneously in the positive direction and the other in the negative direction, the calculation for correcting the changes Δq1, Δq2 in the extrusion volume is performed by adding a positive number as described above. For this reason, if one of the change amounts Δq1, Δq2 of the extrusion volume decreases, the relationship that the other change amount increases always holds. Therefore, when calculating the changes Δq1, Δq2 in the extrusion volume based on the equations (2 ′) and (7) in step S26-3,
(Dq1 + Δq1) = − (dq2 + Δq2) (8)
The changes Δq1 and Δq2 in the extrusion volume satisfying the above relationship are optimum values.

When the change amounts Δq1, Δq2 of the extrusion volume are obtained in step S26-3, the extrusion volumes q1, q2 are corrected and calculated from this and the extrusion volumes q1new, q2new obtained in step S26-1. . That is, the extrusion volumes q1 and q2 are
q1 = q1new + Δq1 (9)
q2 = q2new + Δq2 (10)
(Step S26-4). When either one of the extrusion volumes q1 and q2 calculated by the above formulas (9) and (10) exceeds the maximum value qmax of the extrusion volumes of the pump motors 12 and 13, the above-mentioned first Similar to the control in step S16-5 in the control example, the extrusion volumes q1 and q2 of the pump motors 12 and 13 corresponding to the target gear ratio are obtained from, for example, a map as shown in FIG.

  When the extrusion volumes q1 and q2 of the pump motors 12 and 13 are corrected and calculated in this way, the process returns to the main flowchart of FIG. 6 and the speed B is changed based on the corrected extrusion volumes q1 and q2. Shift control is executed (step S27). Then, this routine is once ended.

  The behavior of the gear ratio γ, the extrusion volumes q1 and q2 of the pump motors 12 and 13 and the discharge pressure p of the pump motors 12 and 13 when the second control example is executed is shown in the time chart of FIG. It is shown. In the time chart of FIG. 8, the shift control by the shift A is executed in the period before the time t21, the sudden shift is requested at the time t21, and from the time t21 to the time t22 at which the sudden shift request ends. In this period, the shift control by the shift B is executed, the shift control by the shift C is started from the time t22, and the shift to the shift A is completed at the time t23.

  If the start of a sudden shift is requested at the time t21 in a state where the shift control by the shift A is being executed, a control for switching the shift mode from the shift A to the shift B is performed accordingly. In this control example, as described above, the change amounts Δq1, Δq2 of the extrusion volumes are calculated so that the larger change amount among the change amounts Δq1, Δq2 of the pump motors 12, 13 is minimized. The extrusion volumes q1 and q2 of the pump motors 12 and 13 for setting the target gear ratio are corrected and set. That is, when switching from the state in which the shift control by the shift A is executed to the state in which the shift control by the shift B is executed, in other words, from the state where the gear ratio is set in the first shift mode, the shift is performed in the second shift mode. Is executed, the extrusion volumes q1 and q2 of the pump motors 12 and 13 are set to extrusion volumes that minimize the amount of change from the current extrusion volume among the extrusion volumes that can set the target gear ratio.

  Therefore, in the state where the shift mode is switched from the shift A to the shift B and the shift control by the shift B is performed (control during the period from the time t21 to the time t22), the pump motors 12 for setting the target gear ratio, For the 13 extrusion volumes q1 and q2, an extrusion volume that minimizes the amount of change from the current extrusion volume is selected. That is, the extrusion volumes q1 and q2 that minimize the amount of change in the extrusion volume are selected from the combinations of the extrusion volumes that set the target speed ratio.

  Therefore, when switching from the state in which the gear ratio is set at the gear shift A to the state in which the gear ratio is set at the gear shift B, the time required to change the extrusion volumes q1 and q2 and the gear ratio γ is shortened. Can be improved. Further, since the extrusion volumes q1 and q2 are controlled to be minimum, the flow amount of the pressure oil is small and the fluctuation of the hydraulic pressure can be suppressed, so that the gear ratio γ fluctuates and a shift shock occurs. It is possible to avoid or suppress the passenger from feeling uncomfortable.

  Further, after the shift mode is switched from the shift A to the shift B, the request for the sudden shift is terminated at the time t22, and the shift mode is switched from the shift B to the shift A (in the period from the time t22 to the time t23). Control) is the same control as in the first control example, that is, the control by the shift C for switching the shift mode from the shift B to the shift A is executed. The shift mode can be switched from the shift B to the shift A without changing the speed ratio γ.

  As described above, according to the transmission control device of the present invention, when setting the transmission gear ratio, the transmission A, the transmission B, and the transmission B are changed depending on how the extrusion volumes q1 and q2 of the pump motors 12 and 13 are changed. It is possible to set three shift modes of the shift C, and each shift mode is appropriately selected and set based on the traveling state of the vehicle. Therefore, for example, the extrusion volumes q1 and q2 of the pump motors 12 and 13 are simultaneously changed to perform a responsive shift, and the extrusion volumes q1 and q2 are prevented so that the discharge pressure p of the pump motors 12 and 13 does not increase. Can be changed to reduce the power loss and to improve the fuel efficiency, and to change the speed with less shock.

  Here, the relationship between the above-described specific example and the present invention will be briefly described. The functional means of steps S13, S15, S16, S24, S25, and S27 described above correspond to the shift control means of the present invention. The functional means of S12 and S22 correspond to the traveling determination means of this invention. Further, the functional means of steps S12, S14, S22, and S23 correspond to the shift mode selection means of the present invention.

It is a flowchart for demonstrating the 1st control example in the control apparatus of this invention. It is a flowchart for demonstrating the detail of the control content of step S16 in the flowchart of FIG. It is an example of the map used in order to obtain | require the extrusion volume of the fluid pressure pump motor according to a target gear ratio, when setting a gear ratio in 2nd speed change mode (speed B). It is an example of the map used in order to obtain | require the extrusion volume of the fluid pressure pump motor according to a target gear ratio, when setting a gear ratio in 1st speed change mode (speed change A). It is a time chart for explaining the behavior of the gear ratio, the extrusion volume of the fluid pressure pump motor, and the discharge pressure of the fluid pressure pump motor when the control shown in the first control example is executed. It is a flowchart for demonstrating the 2nd control example in the control apparatus of this invention. It is a flowchart for demonstrating the detail of the control content of step S26 in the flowchart of FIG. It is a time chart for explaining the behavior of the gear ratio, the extrusion volume of the fluid pressure pump motor, and the discharge pressure of the fluid pressure pump motor when the control shown in the second control example is executed. It is a skeleton figure which shows typically an example of the transmission made into object by this invention. FIG. 10 is a chart collectively showing operation states of pump motors and synchros when setting gear ratios in the transmission shown in FIG. 9.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Power source (E / G), 2 ... Input member, 3 ... 1st planetary gear mechanism, 4 ... 2nd planetary gear mechanism, 8 ... 1st intermediate shaft, 9 ... Motor shaft, 10 ... 2nd intermediate shaft, DESCRIPTION OF SYMBOLS 11 ... Motor shaft, 12 ... Variable displacement pump motor (first pump motor), 13 ... Variable displacement pump motor (second pump motor), 14, 15 ... Oil passage, 16 ... Output shaft, 17, 18, 19 20 ... Gear pair, 22 ... First synchronizer (first synchronizer), 23 ... Second synchronizer (second synchronizer), 24 ... Third synchronizer (third synchronizer), 25 ... For reverse drive Synchronizer (R synchro), 40 ... Electronic control unit (ECU).

Claims (7)

Provide at least two power transmission paths from the power source to the output member, and change from a state where power is transmitted via one power transmission path to a state where power is transmitted via the other power transmission path In the transmission control device that changes the gear ratio by:
A variable displacement fluid pressure pump motor that is provided for each power transmission path so as to change the torque transmitted through each power transmission path in accordance with the extrusion volume, and communicates with each other so that pressure fluid can be exchanged between them. When,
A first speed change mode in which the speed change ratio is set by changing the push-out volume of the other variable capacity fluid pressure pump motor in a state in which the push-out capacity of one variable capacity type fluid pressure pump motor is fixed; Shift that sets the speed ratio in either the second speed change mode that sets the speed change ratio by changing in opposite directions or the third speed change mode that sets the speed change ratio simultaneously by changing each extrusion volume in the same direction Control means;
Traveling determination means for determining a traveling state of a vehicle in which the transmission is mounted;
A transmission control apparatus comprising: a transmission mode selection unit that selects a transmission mode to be executed by the transmission control unit based on the traveling state determined by the traveling determination unit.   The speed change mode selection means includes means for selecting the second speed change mode when the travel determination means determines that the change width of the gear ratio is large or that a rapid speed change is required. The transmission control device according to claim 1. The speed change mode selecting means includes means for selecting the first speed change mode when a speed change ratio is set in the second speed change mode,
The shift control means includes means for changing each extrusion volume so that the ratio of the change amount of each extrusion volume coincides with the ratio of each extrusion volume when switching from the second shift mode to the first shift mode. The transmission control device according to claim 1, wherein:   2. The transmission according to claim 1, wherein the third speed change mode is a speed change mode in which each extrusion volume is changed so that a ratio of a change amount of each extrusion volume matches a ratio of each extrusion volume. Control device.   The shift control means executes the shift by switching from the second shift mode to the third shift mode when switching to the first shift mode during the shift in the second shift mode, 5. The transmission control device according to claim 4, further comprising means for switching from the third speed change mode to the first speed change mode after the volume reaches the maximum.   The speed change control means is configured to set a target speed ratio to an extrusion volume of the fluid pressure pump motor when a speed change is executed in the second speed change mode from a state where the speed change ratio is set in the first speed change mode. 6. The transmission control apparatus according to claim 1, further comprising means for setting an extrusion volume at which a change amount from the current extrusion volume is a minimum among the volumes.   Each power transmission path includes an input element to which torque is transmitted from the power source, a reaction force element to which the variable displacement fluid pressure pump motor is connected, and an output element for outputting torque to the output member. 7. A power transmission mechanism, and a transmission mechanism provided between the output element and the output member and having a different speed ratio for each power transmission path. 8. The transmission control device described.

Images