JP2018096452A - Driving device for transmission - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure which can increase the output of a driving device without increasing the size of a hydraulic power source.SOLUTION: A driving device for transmission includes an actuator which displaces a sleeve for connecting and disconnecting power transmission between a rotational shaft of a transmission and a speed change gear, a hydraulic power source, an oil passage communicating a hydraulic power source and a hydraulic chamber of the actuator, and a solenoid type pressure booster which is connected to the oil passage and increases the oil pressure in the hydraulic chamber in operation.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a transmission drive device.

  2. Description of the Related Art Conventionally, a vehicle including an automatic transmission (generally referred to as “automated manual transmission (AMT)”) having a clutch capable of connecting and disconnecting rotational power transmitted from an engine to a transmission is known. (For example, see Patent Document 1).

  The automatic transmission changes a gear ratio (gear shift) between an input shaft and an output shaft by changing engagement / disengagement between a plurality of sleeves driven by a hydraulic drive device (actuator) and a plurality of transmission gears. Change). Specifically, when changing the gear stage, the automatic transmission releases the engagement of the sleeve and the transmission gear corresponding to the gear stage before the change by the driving device, and corresponds to the gear stage after the change. Engage the sleeve and the transmission gear.

Japanese Patent Application Laid-Open No. 11-0669509

  By the way, the above-described driving device has the following problems with respect to a situation where the driving force necessary for the speed change operation temporarily increases.

  That is, in the above situation, if the output of the driving device is not sufficient, the time required for the shift operation increases. As a countermeasure, it is conceivable to increase the hydraulic power source (hydraulic pump) of the driving device to increase the driving force of the driving device. However, if the pump is increased in size, the fuel consumption may deteriorate.

  The objective of this indication is to propose the structure of the drive device for transmissions which can enlarge the output of a drive device, without enlarging a hydraulic pressure source.

  The present disclosure includes an actuator for displacing a sleeve for connecting / disconnecting power transmission between a rotation shaft of a transmission and a transmission gear, a hydraulic source, an oil passage communicating the hydraulic source and the hydraulic chamber of the actuator, It is directed to a transmission drive device that is connected to an oil passage and includes a solenoid-type pressure increasing device that increases the hydraulic pressure of the hydraulic chamber during operation.

  According to the transmission drive device according to the present disclosure, the output of the drive device can be increased without increasing the size of the hydraulic pressure source.

Schematic diagram conceptually showing the peripheral configuration of an automatic transmission Schematic diagram showing a first embodiment of a transmission drive device according to the present disclosure. Schematic diagram showing a state where the actuator is in the first position Schematic diagram showing the actuator in the second position Schematic diagram showing a state where the actuator is in the third position Operation chart showing the state of each part during shifting

[1 About Embodiment 1]
Hereinafter, Embodiment 1 of the transmission drive device according to the present disclosure will be described in detail with reference to the drawings. Note that the transmission drive device according to the present disclosure is not limited to the first embodiment described below.

[1.1 Peripheral configuration of automatic transmission]
First, the peripheral configuration of the self-propelled transmission will be described with reference to FIG. FIG. 1 is a schematic diagram conceptually showing a peripheral configuration of an automatic transmission in which a transmission drive device according to Embodiment 1 is incorporated.

  As shown in FIG. 1, the vehicle 1 includes an engine 10 and a dual clutch transmission (hereinafter referred to as “DCT”) 2 that is an automatic transmission. The drive wheels are connected to the output side of the DCT 2 through a propeller shaft and a differential gear (not shown) so that power can be transmitted.

  The engine 10 is, for example, a diesel engine. The output rotation speed and output torque of the engine 10 are controlled by the control device 30 based on the accelerator opening of the accelerator pedal detected by the accelerator opening sensor 12. An engine speed sensor 13 for detecting the engine speed is provided on the output shaft 11 of the engine 10.

[1.2 Automatic transmission (DCT)]
The DCT 2 includes a first clutch 20, a second clutch 21, and a transmission unit 22.

  The first clutch 20 is a hydraulically operated wet multi-plate clutch having a plurality of first input side clutch plates 200 and a plurality of first output side clutch plates 201.

  The first input side clutch plate 200 rotates integrally with the output shaft 11 of the engine 10. On the other hand, the first output side clutch plate 201 rotates integrally with the first input shaft 220 of the transmission unit 22.

  The first clutch 20 is urged by a return spring (not shown) in a direction in which the first clutch 20 is in the “disengaged” state. When the first piston 202 is displaced by the clutch operating oil pressure, the first input side clutch plate 200 and the first output side clutch plate 201 are brought into pressure contact with each other, and the first clutch 20 is brought into a “contact” state.

  When the first clutch 20 is in the “contact” state, the power of the engine 10 is transmitted to the first input shaft 220. When the first clutch 20 is “disengaged”, the power of the engine 10 is not transmitted to the first input shaft 220. Switching between the “disengaged” state and the “contact” state of the first clutch 20 is controlled by the control device 30.

  The second clutch 21 is a hydraulically operated wet multi-plate clutch having a plurality of second input side clutch plates 210 and a plurality of second output side clutch plates 211.

  The second input side clutch plate 210 rotates integrally with the output shaft 11 of the engine 10. On the other hand, the second output side clutch plate 211 rotates integrally with the second input shaft 221 of the transmission unit 22.

  The second clutch 21 is urged in a “disconnected” state by a return spring (not shown). When the second piston 212 is displaced by the clutch operating oil pressure, the second input side clutch plate 210 and the second output side clutch plate 211 are brought into pressure contact with each other, and the second clutch 21 is brought into a “contact” state.

  When the second clutch 21 is in the “contact” state, the power of the engine 10 is transmitted to the second input shaft 221. When the second clutch 21 is “disengaged”, the power of the engine 10 is not transmitted to the second input shaft 221. Switching between the “disengaged” state and the “contacted” state of the second clutch 21 is controlled by the control device 30.

  The second clutch 21 is provided on the outer diameter side of the first clutch 20. Further, the first input shaft 220 is provided with a lubricating oil passage (not shown) including an axial oil passage and a plurality of radial oil passages.

  Lubricating oil is injected radially from the first input shaft 220, whereby the clutch plates 200 and 201 of the first clutch 20 and the clutch plates 210 and 211 of the second clutch 21 are cooled. The lubricating oil that has cooled each clutch plate flows out from the outer diameter side of the second clutch 21 and the like.

  The transmission unit 22 includes a first input shaft 220, a second input shaft 221, a counter shaft 222, an output shaft 223, a first transmission unit 230, a second transmission unit 240, a third transmission unit 250, And an output unit 260.

The first input shaft 220 is connected to the output side of the first clutch 20.
The second input shaft 221 is connected to the output side of the second clutch 21.
The auxiliary shaft 222 is disposed in parallel with the first input shaft 220 and the second input shaft 221.
The output shaft 223 is disposed coaxially with the first input shaft 220 and the second input shaft 221. A vehicle speed sensor 14 that detects the speed of the vehicle 1 is provided at the rear end of the output shaft 223.

  The first transmission unit 230 includes a first gear train 231 and a first coupling mechanism 234.

  The first gear train 231 is provided with a first input gear 232 provided so as to be rotatable relative to the first input shaft 220, and a first input gear 232 that is engaged with the first input gear 232 and rotates integrally with the auxiliary shaft 222. 1 sub gear 233.

  The first coupling mechanism 234 includes a first sleeve 236 that rotates together with the first input shaft 220, and a first drive device 235.

  The first driving device 235 displaces the first sleeve 236 in the axial direction (left-right direction in FIG. 1). In this way, the first coupling mechanism 234 has a state in which the first sleeve 236 and the first input gear 232 are engaged (hereinafter referred to as “engaged state”) and a state in which they are not engaged (hereinafter referred to as “ "Disengaged state"). In the engaged state, the first input gear 232 rotates integrally with the first input shaft 220.

  In the case of this embodiment, when the first sleeve 236 is engaged with the first input gear 232, a synchronization mechanism (so-called synchromesh) that synchronizes the rotation speeds of the first sleeve 236 and the first input gear 232. Mechanism). Since the structure of such a synchronization mechanism is substantially the same as a conventionally known structure, detailed description thereof is omitted.

  The second transmission unit 240 includes a second gear train 241 and a second coupling mechanism 244.

  The second gear train 241 meshes with the second input gear 242 provided to be rotatable relative to the second input shaft 221 and the second input gear 242 and is provided so as to rotate integrally with the sub shaft 222. 2 sub gears 243.

  The second coupling mechanism 244 includes a second sleeve 246 that rotates together with the second input shaft 221 and a second driving device 245.

  The second driving device 245 displaces the second sleeve 246 in the axial direction (left-right direction in FIG. 1). In this way, the second coupling mechanism 244 switches between the engaged state and the non-engaged state related to the second sleeve 246 and the second input gear 242. In the engaged state, the second input gear 242 rotates integrally with the second input shaft 221.

  The third transmission unit 250 includes a third gear train 251 and a third coupling mechanism 254.

  The third gear train 251 meshes with the third input gear 252 provided to be rotatable relative to the first input shaft 220 and the third input gear 252 and is provided so as to rotate integrally with the auxiliary shaft 222. 3 auxiliary gears 253.

  The third coupling mechanism 254 includes a third sleeve 256 that rotates together with the first input shaft 220, and a third driving device 255.

  The third drive device 255 switches the engaged state and the disengaged state with respect to the third sleeve 256 and the third input gear 252 by displacing the third sleeve 256 in the axial direction (left-right direction in FIG. 1). In the engaged state, the third input gear 252 rotates integrally with the first input shaft 220.

  The output unit 260 includes a forward gear train 261, a reverse gear train 262, and a forward / reverse coupling mechanism 263.

  The forward gear train 261 includes a forward output gear 264 provided so as to be relatively rotatable with respect to the output shaft 223, and a forward secondary gear provided to mesh with the forward output gear 264 and rotate integrally with the secondary shaft 222. 265.

  The reverse gear train 262 meshes with the reverse output gear 266 provided so as to be rotatable relative to the output shaft 223, the reverse output gear 266, and the idler gear 268, and is provided so as to rotate integrally with the auxiliary shaft 222. The reverse reverse gear 267 is provided.

  The forward / reverse coupling mechanism 263 includes a forward / reverse sleeve 269 that rotates together with the output shaft 223, and a forward / reverse drive device 270.

  The forward / reverse drive device 270 displaces the forward / reverse sleeve 269 in the axial direction (left / right direction in FIG. 1). In this way, the forward / reverse drive device 270 selectively engages the forward / backward movement sleeve 269 with one of the forward output gear 264 and the reverse output gear 266.

  The forward output gear 264 rotates integrally with the output shaft 223 in a state where the forward / backward moving sleeve 269 is engaged with the forward output gear 264. On the other hand, the reverse output gear 266 rotates integrally with the output shaft 223 in a state where the forward / reverse sleeve 269 is engaged with the reverse output gear 266.

[1.3 Power transmission path in DCT2]
Next, a brief description will be given of a power transmission path when realizing a gear stage (first speed to third speed in the case of this embodiment) in DCT2.

  First, when realizing the first speed, the first driving device 235 displaces the first sleeve 236 in a direction approaching the first input gear 232. Then, the first sleeve 236 and the first input gear 232 are engaged so as to be integrally rotatable. In this state, the first input gear 232 and the first input shaft 220 are coupled in a state where power transmission and integral rotation are possible.

  Along with the above operation, the forward / reverse drive device 270 displaces the forward / reverse sleeve 269 in a direction approaching the forward output gear 264. Then, the forward / reverse sleeve 269 and the forward output gear 264 are engaged with each other so as to be integrally rotatable. In this state, the forward output gear 264 and the output shaft 223 are coupled in a state where power transmission and integral rotation are possible.

  In the above-described state, the first clutch 20 is brought into the “contact” state to achieve the first speed. Thereby, the power of the engine 10 is transmitted from the first clutch 20 in the order of the first input shaft 220, the first gear train 231, the countershaft 222, the forward gear train 261, and the output shaft 223.

  When realizing the second speed, the second driving device 245 displaces the second sleeve 246 in a direction approaching the second input gear 242. Then, the second sleeve 246 and the second input gear 242 are engaged so as to be integrally rotatable. In this state, the second input gear 242 and the second input shaft 221 are coupled in a state where power transmission and integral rotation are possible. At the same time, the forward output gear 264 and the output shaft 223 are coupled by the forward / reverse coupling mechanism 263.

  In the above state, the second speed is realized by bringing the second clutch 21 into the “contact” state. As a result, the power of the engine 10 is transmitted from the second clutch 21 in the order of the second input shaft 221, the second gear train 241, the sub shaft 222, the forward gear train 261, and the output shaft 223.

  When realizing the third speed, the third coupling mechanism 254 displaces the third sleeve 256 in a direction approaching the third input gear 252. Then, the third sleeve 256 and the third input gear 252 are engaged so as to be integrally rotatable. In this state, the third input gear 252 and the first input shaft 220 are coupled in a state where power transmission and integral rotation are possible. At the same time, the forward output gear 264 and the output shaft 223 are coupled by the forward / reverse coupling mechanism 263.

  In this state, the third speed is realized by bringing the first clutch 20 into the “contact” state. Thereby, the power of the engine 10 is transmitted from the first clutch 20 in the order of the first input shaft 220, the third gear train 251, the countershaft 222, the forward gear train 261, and the output shaft 223.

  The shift stage of the DCT 2 realized as described above is determined by the control device 30 based on travel information such as the accelerator opening and the vehicle speed. When the shift speed to be realized (for example, the first speed) is determined, the control device 30 drives the transmission drive device (for example, the first drive apparatus 235) corresponding to the shift speed to be realized, and the above-described sleeves ( For example, the first sleeve 236) is displaced in the axial direction.

[1.4 Transmission drive unit]
Hereinafter, the structure of the transmission drive device 40 of this embodiment will be described with reference to FIGS. The first to third driving devices 235, 245, 255 and the forward / reverse driving device 270 shown in FIG. 1 correspond to the transmission driving device 40, respectively.

  The transmission drive device 40 includes an actuator 41 and a hydraulic mechanism 42.

[1.4.1 Actuator]
The actuator 41 is driven by a hydraulic mechanism to be described later, and for example, displaces a sleeve (for example, the first sleeve 236) of an automatic transmission (for example, DCT2) in the axial direction.

  The actuator 41 includes a cylindrical cylinder 411 and a piston 414 including a piston body 412 and a piston shaft portion 413.

  The internal space of the cylinder 411 is divided into a first hydraulic chamber 415 (the left hydraulic chamber in FIG. 2) and a second hydraulic chamber 416 (the right hydraulic chamber in FIG. 2) by the piston body 412.

  One axial end portion (left end portion in FIG. 2) of the piston shaft portion 413 is fixed to the piston main body portion 412. On the other hand, the other axial end portion (right end portion in FIG. 2) of the piston shaft portion 413 protrudes from the other axial end surface (right end surface in FIG. 2) of the cylinder 411 to the outside.

  The other axial end portion of the piston shaft portion 413 is connected to a sleeve (for example, the first sleeve 236) via a coupling mechanism (for example, a shift fork or the like) (not shown).

[1.4.2 Hydraulic mechanism]
The hydraulic mechanism 42 includes a first hydraulic mechanism 42a and a second hydraulic mechanism 42b.

  The first hydraulic mechanism 42a includes a hydraulic pressure source 43, an oil passage 44a, a check valve 45a, an electromagnetic valve 46a, and a pressure booster 47a.

  On the other hand, the second hydraulic mechanism 42b includes a hydraulic pressure source 43, an oil passage 44b, a check valve 45b, an electromagnetic valve 46b, and a pressure booster 47b. The hydraulic pressure source 43 of the second hydraulic mechanism 42b is the same as that of the first hydraulic mechanism 42a. Since the other second hydraulic mechanism 42b has the same structure as the first hydraulic mechanism 42a, only the first hydraulic mechanism 42a will be described below.

  The hydraulic pressure source 43 is a hydraulic pump that is driven by the engine 10 that is a drive source of the vehicle or an electric motor (not shown) that is a drive source different from the engine 10. Such a hydraulic source 43 sucks up the hydraulic oil from the oil tank 60 and pressurizes it. Then, pressurized hydraulic oil (that is, pressure oil) is discharged to an oil passage 44a described later. The hydraulic oil discharged from the hydraulic power source 43 is regulated to a predetermined pressure (hereinafter referred to as “original pressure”) by a pressure regulating valve (not shown).

  The oil passage 44a is constituted by a hydraulic pipe or the like, and communicates the discharge port of the hydraulic power source 43 and the first hydraulic chamber 415 of the cylinder 411 in a state where hydraulic fluid can flow.

  Such an oil passage 44 a includes a first oil passage 441, a second oil passage 442, and a third oil passage 443.

  The first oil passage 441 is provided between a discharge port of the hydraulic pressure source 43 and a check valve 45a described later. The second oil passage 442 is provided between the check valve 45a and an electromagnetic valve 46a described later.

  The third oil passage 443 is provided between the electromagnetic valve 46 a and the first hydraulic chamber 415 of the cylinder 411.

  The check valve 45 a is provided between the first oil passage 441 and the second oil passage 442. Such a check valve 45 a prevents backflow of hydraulic oil from the second oil passage 442 to the first oil passage 441.

  In addition, when the pressure in the second oil passage 442 becomes smaller than the pressure in the first oil passage 441 (that is, the original pressure), the check valve 45a causes the hydraulic oil to flow from the first oil passage 441 to the second oil passage. 442 can be distributed.

  The electromagnetic valve 46 a is provided between the second oil passage 442 and the third oil passage 443. Such an electromagnetic valve 46a switches between a state in which the second oil passage 442 and the third oil passage 443 are communicated and a state in which they are not in communication, based on energization. The operation of the electromagnetic valve 46a is controlled by the control device 30.

  Specifically, the electromagnetic valve 46a allows the second oil passage 442 and the third oil passage 443 to communicate with each other in an energized state. On the other hand, the solenoid valve 46 a drains the hydraulic oil in the third oil passage 443 to the oil tank 60 in a non-energized state.

  The pressure booster 47 a is a solenoid-driven actuator, and includes a pressure increase side cylinder 471, a pressure increase side piston 472, a solenoid 473, and a supply oil passage 474.

  The pressure-increasing side cylinder 471 has a cylindrical inner space.

  The pressure-increasing side piston 472 is disposed in the internal space of the pressure-increasing side cylinder 471 so as to be capable of axial displacement. The base end portion of the pressure-increasing side piston 472 is connected to a solenoid 473 described later.

  Of the internal space of the pressure increasing side cylinder 471, the pressure increasing side cylinder space 476 defined by the tip surface of the pressure increasing side piston 472, the inner peripheral surface of the pressure increasing side cylinder 471 and one side wall 475 of the pressure increasing side cylinder 471 operates. Filled with oil.

  The solenoid 473 displaces the pressure-increasing side piston 472 in the axial direction (left-right direction in FIG. 2) with a driving force corresponding to the load current. The operation of the solenoid 473 is controlled by the control device 30.

  The supply oil passage 474 communicates the pressure-increasing side cylinder space 476 and the second oil passage 442 in a state in which hydraulic fluid can flow. Such a supply oil passage 474 is also filled with hydraulic oil.

  As described above, the pressure-increasing side cylinder space 476 and the supply oil passage 474 are filled with hydraulic oil. In this state, the hydraulic pressure of the hydraulic oil in the pressure-increasing side cylinder space 476 and the supply oil passage 474 is equal to the hydraulic pressure of the hydraulic oil in the second oil passage 442.

  In the case of the pressure increasing device 47a as described above, when the solenoid 473 attempts to displace the pressure increasing side piston 472 in a direction in which the pressure increasing side cylinder space 476 becomes smaller (hereinafter referred to as “pressure increasing direction”), the pressure increasing piston 472 is. The front end surface presses the hydraulic oil in the pressure-increasing side cylinder space 476 and the pressure in the portion communicating with the pressure-increasing side cylinder space 476 is increased.

[1.4.2 Operation of transmission drive unit]
Next, the operation of the transmission drive device 40 according to this embodiment will be described with reference to FIGS. In the following description, the operation of the transmission drive device 40 when realizing the first speed of the above-described DCT 2 will be described. The operation for realizing a gear other than the first speed is the same as that described below except that the driven sleeve is different.

  First, the operation of the transmission drive device 40 when realizing the first speed of the DCT 2 without operating the pressure booster 47a will be described.

  In the DCT 2, the first sleeve 236 and the first input gear 232 are in a disengaged state when the first speed is not realized. In this disengaged state, the actuator 41 is in the first state shown in FIGS.

  In the first state of the actuator 41, hydraulic oil is not supplied to the first hydraulic chamber 415 and the second hydraulic chamber 416.

  In the first state of the actuator 41, the hydraulic oil pressure in the first oil passage 441, the second oil passage 442, the supply oil passage 474, and the pressure-increasing side cylinder space 476 of the first hydraulic mechanism 42a and the second hydraulic mechanism 42b is Source pressure.

  When the electromagnetic valve 46a of the first hydraulic mechanism 42a is energized from the first state of the actuator 41, the electromagnetic valve 46a is energized. The electromagnetic valve 46b of the second hydraulic mechanism 42b is in a non-energized state.

  Then, the electromagnetic valve 46a of the first hydraulic mechanism 42a causes the second oil passage 442 and the third oil passage 443 to communicate with each other. As a result, hydraulic oil is supplied from the second oil passage 442 through the electromagnetic valve 46 a and the third oil passage 443 to the first hydraulic chamber 415.

  When the first hydraulic chamber 415 is filled with the hydraulic oil, the hydraulic oil displaces the piston 414 to one axial side (the right side in FIGS. 2 and 3A). Along with this displacement, the first sleeve 236 is displaced in a direction approaching the first input gear 232.

  At an intermediate position in the stroke range L of the piston 414, the actuator 41 enters the second state shown in FIG. 3B. In such a second state, the first sleeve 236 and the first input gear 232 start to engage. That is, the rotation speed of the first sleeve 236 and the first input gear 232 is synchronized by the synchronization mechanism.

  When the piston 414 is further displaced from the second state, the actuator 41 enters the third state shown in FIG. 3C. In such a third state, the first sleeve 236 and the first input gear 232 are completely engaged. As a result, the first speed of DCT2 is realized.

  In the state shown in FIG. 3C, the solenoid valve 46 a is turned off, and the hydraulic oil in the first hydraulic chamber 415 is drained to the oil tank 60. In the case of this embodiment, a structure (for example, a detent mechanism) that restricts displacement in the axial direction of the piston 414 in the third state is provided.

  On the other hand, when realizing another shift speed, a sleeve (for example, the second sleeve 246) corresponding to the other shift speed (for example, the second speed) and an input gear (for example, the second input gear 242) are engaged. At the same time, the engagement between the first sleeve 236 and the first input gear 232 is released.

  Specifically, when the solenoid valve 46b of the second hydraulic mechanism 42b is energized from the third state (see FIG. 3C), the solenoid valve 46b is energized. Note that the solenoid valve 46a of the first hydraulic mechanism 42a remains unenergized.

  Then, the electromagnetic valve 46 b allows the second oil passage 442 and the third oil passage 443 to communicate with each other. As a result, hydraulic oil is supplied from the second oil passage 442 through the electromagnetic valve 46 b and the third oil passage 443 to the second hydraulic chamber 416.

  When the second hydraulic chamber 416 is filled with hydraulic oil, the hydraulic oil displaces the piston 414 to the other side in the axial direction (left side in FIGS. 2 and 3C). With such displacement, the first sleeve 236 is displaced in a direction away from the first input gear 232. At the intermediate position (position shown in FIG. 3B) of the stroke range L of the piston 414, the engagement between the first sleeve 236 and the first input gear 232 starts to be released.

  When the piston 414 is displaced from the second state (see FIG. 3B) to the first state (see FIG. 3A), the engagement between the first sleeve 236 and the first input gear 232 is completely released.

  In the first state, the electromagnetic valve 46 b is deenergized, the electromagnetic valve 46 b is closed, and the hydraulic oil in the second hydraulic chamber 416 is drained to the oil tank 60. In the case of this embodiment, a structure (for example, a detent mechanism) that restricts displacement of the piston 414 in the axial direction is provided in the first state.

  The above is the operation of the transmission drive device 40 in the case where the first speed of the DCT 2 is realized in a state where the pressure increasing device 47a is not operated. Hereinafter, the operation of the transmission drive device 40 when the pressure increasing device 47a is operated will be described.

  Note that the pressure intensifying device 47a may always be operated, or may be operated only when a predetermined condition is met.

  Examples of the predetermined condition include a case where the outside air temperature or the temperature of gear oil existing in a gear case (not shown) of the transmission is lower than a predetermined threshold.

  Such hydraulic oil has high viscosity at low temperatures. For this reason, the rotational resistance (in other words, moment of inertia) of each gear of the DCT 2 increases due to the influence of the viscosity of the hydraulic oil. As a result, in order to perform the shifting operation of the DCT 2 with a normal feeling, a driving force larger than usual may be required for the transmission driving device 40.

  Further, the predetermined condition also corresponds to a situation where a driving force (in other words, necessary thrust described later) that is temporarily larger than normal is temporarily required in the shifting operation of the DCT 2. As such a situation, specifically, there is a situation in which the rotation speed of the sleeve and the input gear is synchronized by the synchronization mechanism. Note that the predetermined condition is not limited to the above-described condition.

  Hereinafter, the operation of the transmission drive device 40 when the pressure increasing device 47a is operated in a situation where a driving force larger than normal is temporarily required will be described with reference to FIGS. The operation of the parts other than the pressure booster 47a is almost the same as that described above. The following description also explains the operation of the transmission drive device 40 when realizing the first speed of the DCT 2.

  FIG. 4 is an operation chart for explaining the state of each part from the start to the end of the speed change operation.

When starting the shift operation at time _{t 1} shown in FIG. 4, the first state of the actuator 41 shown in FIG. 2, 3A, of the electromagnetic valve 46a of the first hydraulic mechanism 42a energized (Fig. 4 "ON" State). On the other hand, the electromagnetic valve 46a of the second hydraulic mechanism 42b remains in a non-energized state.

In the state before the start of the speed change operation (that is, time t ₁ ), the state of each part shown in FIG. 4 is as follows.
“Piston displacement” → “0”
“Solenoid valve” → “OFF”
“Necessary thrust” → “0”
“Predetermined conditions” → “OFF”
“Pressure booster” → “OFF”

  “Piston displacement” is “0 (zero)” when the piston 414 is in the first state position (ie, initial position) of the actuator 41 shown in FIGS. Regarding “predetermined conditions”, as described above, “ON” corresponds to a situation in which a driving force (necessary thrust to be described later) that is temporarily larger than normal is required, and “OFF” indicates that it does not correspond to the same. Is.

Further, the “necessary thrust” is a thrust (driving force) required for the transmission drive device 40 during the shifting operation. As an example of the necessary thrust, the necessary thrust in the case where the above-described predetermined condition is not satisfied (normal time) is set to “F ₁ ”, and in a predetermined state (that is, a state where a driving force larger than usual is temporarily required). The required thrust in the case where it corresponds is assumed to be “F ₂ ”. “F ₂ ” is larger than “F ₁ ” (F ₂ > F ₁ ).

On the other hand, in the state of time t ₁ shown in FIG. 4, the state of each part shown in FIG. 4 is a state transition as follows.
“Piston displacement” → “0”
“Solenoid valve” → “ON”
“Necessary thrust” → “F ₁ ”
“Predetermined conditions” → “OFF”
“Pressure booster” → “OFF”

That is, the necessary thrust is set to F ₁ in the state at time t ₁ shown in FIG. Further, although the electromagnetic valve 46b is opened, the piston 414 has not yet been displaced from the initial position. In this state, the predetermined condition is not met and the pressure increasing device is not operating. That is, during the period from time t ₁ shown in FIG. 4 to time t ₂ described later, a normal speed change operation in which the pressure increasing device 47a is not operated is executed.

  When the solenoid valve 46 a is energized as described above, hydraulic oil flows from the second oil passage 442 through the solenoid valve 46 a and the third oil passage 443 and is supplied to the first hydraulic chamber 415.

  When the first hydraulic chamber 415 is filled with the hydraulic oil, the hydraulic oil displaces the piston 414 to one axial side (the right side in FIGS. 2 and 3A). As the piston 414 is displaced, the first sleeve 236 is displaced in a direction approaching the first input gear 232.

When the piston 414 is displaced by half (L / 2) of the stroke range L (time t ₂ shown in FIG. 4), the actuator 41 enters the second state shown in FIG. 3B.

  In the second state, the first sleeve 236 and the first input gear 232 start to engage. That is, the rotation speed of the first sleeve 236 and the first input gear 232 is synchronized by the synchronization mechanism.

  Since this state corresponds to the aforementioned predetermined state, a current flows through the solenoid 473 of the pressure increasing device 47a in order to operate the pressure increasing device 47a.

Each part of the state at time t ₂ shown in FIG. 4 is less.
“Piston displacement” → L / 2
“Solenoid valve” → “ON”
“Necessary thrust” → “F ₂ ”
“Predetermined conditions” → “ON”
“Pressure booster” → “ON”

That is, the required thrust is set to F ₂ in the state at time t ₂ shown in FIG. Further, the electromagnetic valve 46b is in an open state, and the piston 414 is displaced by L / 2 from the initial position. In this state, a predetermined condition is met and the pressure booster is activated. That is, during the period from time t ₂ shown in FIG. 4 to time t ₃ to be described later, the speed change operation is executed with the pressure increasing device 47a operating.

  When a current flows through the solenoid 473, the solenoid 473 attempts to displace the pressure-increasing piston 472 in the pressure increasing direction (right side in FIG. 2) with a driving force corresponding to the load current.

The current flowing through the solenoid 473, so that the driving force from the piston 414 applied to the first sleeve 236 (thrust) is required thrust _{F 2,} is adjusted by the control device 30.

  Then, the tip of the pressure increasing piston 472 presses the hydraulic oil in the pressure increasing side cylinder space 476 with a pressing force corresponding to the driving force, and the hydraulic pressure of the hydraulic oil in the portion communicating with the pressure increasing side cylinder space 476 is increased. The The communicating parts are the supply oil passage 474, the second oil passage 442, the third oil passage 443, and the first hydraulic chamber 415.

  As a result, the hydraulic pressure of the hydraulic oil in the first hydraulic chamber 415 is increased, and the thrust (driving force) that the piston 414 receives from the hydraulic oil in the first hydraulic chamber 415 is increased. At the same time, the thrust (drive force) in the direction approaching the first input gear 232 applied from the piston 414 to the first sleeve 236 is also increased.

At time t ₃ when 4, no longer corresponds to the predetermined condition (that is, synchronization is completed by the synchronizing mechanism) and to stop the operation of the pressure boosting device 47a (i.e., stopping the energization of the solenoid 473 To do). Incidentally, without stopping the operation of the pressure boosting device 47a at time t ₃ when shown in FIG. 4, for example, it may activate the pressure increasing device 47a until time t ₄ when shown in Fig.

As a result, the state of each part shown in FIG. 4 is as follows.
“Piston displacement” → L / 2
“Solenoid valve” → “ON”
“Necessary thrust” → “F ₁ ”
“Predetermined conditions” → “OFF”
“Pressure booster” → “OFF”

That is, in the state of the time t ₃ when 4, required thrust is set to the desired thrust F ₁ at the time of normal. The electromagnetic valve 46b is opened, and the piston 414 is displaced from the initial position by L / 2. In this state, the predetermined condition is not met and the pressure increasing device is not operating. In other words, the time t ₃ after shown in FIG. 4, the normal shift operation pressure boosting device 47a is not in operation is executed.

Piston 414 and further displaced from the position in the second state shown in FIG. 3B (the state of the time shown in FIG. 4 t _3), the state of the actuator 41 is time t ₄ when shown in the third state (Fig. 4 shown in FIG. 3C ) In such a third state, the first sleeve 236 and the first input gear 232 are completely engaged, and the first speed of the DCT 2 is realized.

Incidentally, at time t ₄ when FIG. 4, the state of each part shown in FIG. 4 is as follows.
"Piston displacement" → L
“Solenoid valve” → “OFF”
“Necessary thrust” → “0”
“Predetermined conditions” → “OFF”
“Pressure booster” → “OFF”

That is, in the state of the time t ₄ when FIG. 4, required thrust is set to 0 (zero). The electromagnetic valve 46b is closed, and the piston 414 is displaced by L from the initial position. In this state, the predetermined condition is not met and the pressure increasing device is not operating.
The other operations are the same as those in the case where the above-described pressure increasing device 47a is not operated, and thus the description thereof is omitted.

[1.5 Addendum]
In the above description, the operation when realizing the first speed of DCT 2 has been described as an example. However, the operation when realizing the other shift speeds is other than selecting the sleeve and the input gear corresponding to the other shift speeds. Is the same as the above-described operation.

  Further, the second hydraulic mechanism 42b may be always operated as in the case of the first hydraulic mechanism 42a, or may be operated only when a predetermined condition is satisfied.

  In the present embodiment, the case where DCT as an example of an automatic transmission is employed has been described. However, AMT may be adopted as the automatic transmission.

  In the first embodiment, the DCT 2 of the transmission drive device 40 corresponds to a “transmission”. Further, the first input shaft 220, the second input shaft 221 and the output shaft 223 correspond to “rotating shafts”.

  The first input gear 232, the second input gear 242, the third input gear 252, the forward output gear 264, and the reverse output gear 266 correspond to “transmission gears”.

  The first sleeve 236, the second sleeve 246, the third sleeve 256, and the forward / reverse sleeve 269 correspond to “sleeves”.

  Further, the actuator 41 corresponds to an “actuator”, and the pressure boosters 47 a and 47 b correspond to a “solenoid pressure booster”. However, the configuration of the transmission drive device according to the present disclosure is not limited to the configuration of the first embodiment.

[1.6 Actions and effects of this embodiment]
According to the transmission drive device 40 of the present embodiment, in addition to the hydraulic pressure source 43, solenoid pressure boosters 47a and 47b are provided. For this reason, the output (driving force) of the transmission drive device 40 can be increased without increasing the size of the hydraulic pressure source 43. That is, in the case of the present embodiment, when the driving force (for example, the required thrust F ₂ ) larger than the normal driving force (for example, the required thrust F ₁ ) is required for the transmission drive device 40, the pressure increase is performed. It is possible to increase the output (driving force) of the transmission driving device 40 by operating the devices 47a and 47b. For this reason, it is not necessary to increase the size of the hydraulic pressure source 43 in order to increase the output of the transmission drive device 40. As a result, it is possible to reduce the burden on the engine 10 that is the power source of the hydraulic power source 43 as compared with the case where the hydraulic power source 43 is enlarged. In other words, deterioration of fuel consumption can be suppressed as compared with the case where the hydraulic pressure source 43 is enlarged.

  In the case of the present embodiment, the pressure boosters 47a and 47b can be operated according to the timing when the output of the transmission drive device 40 needs to be increased. In other words, when there is no need to increase the output of the transmission drive device 40, the pressure boosters 47a and 47b can be turned off. For this reason, the power consumption in the pressure boosters 47a and 47b does not increase easily.

  In addition, the above-described pressure-increasing devices 47a and 47b can provide the above-described functions and effects by being provided at arbitrary positions in the oil passages 44a and 44b. For this reason, the freedom degree of the design regarding arrangement | positioning of the pressure booster 47a, 47b becomes high.

  The transmission drive device according to the present disclosure is useful as a drive device for various automatic transmissions.

2 DCT
220 First input shaft 232 First input gear 236 First sleeve 40 Transmission drive device 41 Actuator 415 First hydraulic chamber 43 Hydraulic source 47a, 47b Booster 473 Solenoid

Claims (2)

An actuator for displacing a sleeve for connecting and disconnecting power transmission between the rotation shaft of the transmission and the transmission gear;
A hydraulic source;
An oil passage communicating the hydraulic source and the hydraulic chamber of the actuator;
A solenoid-type pressure increasing device that is connected to the oil passage and increases the hydraulic pressure of the hydraulic chamber during operation;
Transmission device for transmission. A check valve and a solenoid valve are provided in the oil passage,
The transmission drive device according to claim 1, wherein the solenoid pressure booster is connected between the check valve and the electromagnetic valve in the oil passage.

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