JP2012047328A - Range switching control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce motor torque necessary for P-range release operation, and to reduce the size and cost of a motor, in a motor-driven range switching mechanism.SOLUTION: When the range switching operation from a P-range is performed, the motor 14 is rotated once slightly in a direction reverse to a range switching direction, and an elastic force is accumulated in a detent mechanism 38. After that, by rotating the motor 14 in the switching direction while making the elastic force accumulated in the detent mechanism 38 act in the range switching direction, motion energy to the range switching direction is increased, and a shift range is switched to a target range from the P-range. Alternatively, when the range switching operation from a range other than the P-range is performed, the motor 14 is immediately rotated in the range switching direction and the shift range is switched to the target range from the P-range without performing motor reverse-rotation operation.

Description

  The present invention relates to a range switching control device that switches a shift range of an automatic transmission between a plurality of ranges including a parking range using a motor as a drive source.

  In recent vehicles, electronic control has progressed, and as described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2006-136035), a driver's range switching operation (shift lever operation) is detected by a switch or the like. A so-called shift-by-wire range switching control system has been developed in which the motor is driven and controlled based on the detection signal to switch the shift range of the range switching mechanism to a target range.

  In such a shift-by-wire range switching control system, when the driver switches the shift range to the parking range (P range), the parking rod is driven to the parking position by the motor, and the cone at the tip of the parking rod is locked. When the lock lever is pushed up by being pushed down, the convex portion of the lock lever is fitted into the parking gear provided on the output shaft of the automatic transmission, and the parking gear is locked. It becomes. In this state, when the driver switches the shift range from the parking range to another range, the parking rod is pulled out from below the lock lever by the driving force of the motor, so that the convex portion of the lock lever is removed from the parking gear. The parking gear is unlocked and the vehicle is allowed to travel.

  Further, as described in Patent Document 2 (Japanese Patent Application Laid-Open No. 2009-121546), particularly when parking on a slope (parking range), the force that the vehicle tries to move due to gravity is applied to the parking gear via the axle. Since this acts on the lock lever, the lock lever is pressed against the parking rod, so that a considerably large motor torque is required for the parking range releasing operation of extracting the parking rod from the lower side of the lock lever. For this reason, in Patent Document 2, control is performed so that the motor torque is maximized during the parking range release operation.

JP 2006-136035 A JP 2009-121546 A

  However, the motor torque changes due to fluctuations in the power supply voltage (battery voltage) and fluctuations in the winding resistance value due to the motor temperature. Further, the torque required for the parking range canceling operation varies depending on the manufacturing variation of the vehicle and changes with time, and also varies depending on the slope of the slope and the vehicle weight (number of passengers). Therefore, in Patent Document 2, it is necessary to mount a high-torque motor that can secure the required torque even under the most severe conditions in consideration of these various fluctuation factors, and the motor is increased in size and cost accordingly. There were drawbacks such as.

  Therefore, the problem to be solved by the present invention is that the motor torque necessary for the parking range canceling operation can be reduced, and the parking range canceling operation is reliably performed while realizing a reduction in size and cost of the motor. It is an object of the present invention to provide a range switching control device capable of performing the above.

  In order to solve the above problems, the invention according to claim 1 is directed to a range switching mechanism that switches a shift range of an automatic transmission between a plurality of ranges including a parking range using a motor as a drive source, and a driver's range switching operation. And a range switching control device comprising: a range switching control unit that switches the shift range to the target range by controlling the driving of the motor, wherein the range switching control unit releases the parking range that switches the shift range from the parking range to the target range. During operation, once the motor is rotated slightly in the direction opposite to the range switching direction, the motor reverse operation is performed, and after the play of the range switching mechanism (backlash of the rotation transmission system) is packed, the motor is moved in the range switching direction. To increase the kinetic energy in the range switching direction, and the shift range is parkin. It is characterized in that switching from the range to the target range. In this way, when the parking range is released, the motor is temporarily rotated slightly in the direction opposite to the range switching direction, thereby creating a motor idle section by the play of the range switching mechanism and accelerating the motor to switch the range. The kinetic energy in the direction can be increased. Thereby, even if the torque of the motor is smaller than the conventional one, the parking range canceling operation can be surely performed, and the motor can be reduced in size and cost.

  According to a second aspect of the present invention, there is provided a range switching mechanism for switching a shift range of an automatic transmission between a plurality of ranges including a parking range using a motor as a drive source, and driving the motor in accordance with a driver's range switching operation. In the range switching control device comprising a range switching control means for controlling and switching the shift range to the target range, the range switching mechanism includes a detent mechanism that engages and holds the shift range in each range with a spring force, and the range The switching control means biases the detent mechanism in the range switching direction by rotating the motor a little in the direction opposite to the range switching direction during the parking range release operation for switching the shift range from the parking range to the target range. Elasticity stored in the detent mechanism after reverse rotation of the motor that stores elastic force The while applying to the range switching direction by rotating the motor in the range switching direction, is characterized in that for switching the shift range by increasing the kinetic energy of the range shift direction from the parking range to the target range.

  The motor-driven range switching mechanism has a detent mechanism that engages and holds the shift range to each range with a spring force. Therefore, the motor is temporarily moved in the direction opposite to the range switching direction once during the parking range release operation. If rotated, the detent mechanism can store an elastic force that urges the detent mechanism in the range switching direction. Therefore, once the motor reverse operation is performed during the parking range release operation and then the motor is rotated in the range switching direction, the motor torque is applied in the range switching direction while accelerating in the range switching direction by the elastic force accumulated in the detent mechanism. It is possible to efficiently increase the kinetic energy to the. Thereby, even if the torque of the motor is smaller than the conventional one, the parking range canceling operation can be surely performed, and the motor can be reduced in size and cost.

  As described above, the motor torque changes due to fluctuations in the power supply voltage (battery voltage) and fluctuations in the winding resistance value due to the motor temperature. Further, the torque required for the parking range canceling operation varies depending on the slope of the parking slope. In the present invention, the motor reverse rotation operation may be performed every time the parking range release operation is performed. However, the time required for the range switching operation from the parking range is increased accordingly.

  In consideration of these points, the power supply voltage detection means for detecting or estimating the power supply voltage supplied to the motor as in claim 3, and the power supply voltage detected or estimated by the power supply voltage detection means during the parking range release operation May be switched from the parking range to the target range without performing the motor reverse rotation operation. In short, if the power supply voltage of the motor is secured above the predetermined voltage, it is judged that the motor torque necessary for the parking range canceling operation is secured, and the parking range is immediately switched to the target range without performing the motor reverse rotation operation. Thus, when the power supply voltage is a normal voltage equal to or higher than a predetermined voltage, the range switching operation from the parking range can be performed with good response.

  Further, as described in claim 4, the vehicle is provided with a hill parking determining means for determining whether or not the parking is hill parking, and is not hill parking by the hill parking determining means during parking range release operation (parking on a flat road surface). If it is determined, the parking range may be switched to the target range without performing the motor reverse rotation operation. In short, if parking on a flat road, the torque required for parking range release operation is considerably smaller than that for slope parking, so if it is determined that parking is not slope parking, the motor torque required for parking range release operation Therefore, when the vehicle is parked on a flat road surface, the range switching operation from the parking range can be performed with good response. It can be carried out.

  According to a fifth aspect of the present invention, the motor temperature detecting means for detecting or estimating the motor temperature is provided, and the motor reverse rotation is performed when the motor temperature detected or estimated by the motor temperature detecting means during the parking range releasing operation is equal to or lower than a predetermined temperature. You may make it switch from a parking range to a target range, without performing operation | movement. In short, if the motor temperature is equal to or lower than the predetermined temperature (winding resistance value is equal to or lower than the predetermined value), it is determined that the motor torque necessary for the parking range release operation is secured, and the parking is immediately performed without performing the motor reverse rotation operation. The range is switched from the range to the target range. With this, when the motor temperature is a normal temperature equal to or lower than the predetermined temperature, the range switching operation from the parking range can be performed with good response.

FIG. 1 is a diagram schematically showing the overall configuration of an engine and automatic transmission control system according to a first embodiment of the present invention. FIG. 2 is a perspective view showing the range switching mechanism of the first embodiment. FIG. 3 is a diagram schematically illustrating the overall configuration of the range switching control device according to the first embodiment. FIG. 4 is a diagram illustrating the torque applied to the tires of the vehicle when parked on a slope. FIG. 5 is a diagram for explaining a mechanism in which torque applied to the tire is transmitted to the parking gear of the automatic transmission. FIG. 6 is a diagram showing a change in torque when shifting from the P range to the D range. FIG. 7 is a diagram showing a change in torque when shifting from the D range to the P range. FIG. 8 is a diagram for explaining a control method of the P range release operation when shifting from the P range to another range. FIG. 9 is a diagram showing a torque change when the P range is released from the P range to shift to the D range. FIG. 10 is a flowchart illustrating a process flow of the P-range release operation control program according to the first embodiment. FIG. 11 is a flowchart illustrating a process flow of the P-range release operation control program according to the second embodiment. FIG. 12 is a flowchart illustrating a process flow of the P-range release operation control program according to the third embodiment. FIG. 13 is a flowchart illustrating a process flow of the P-range release operation control program according to the fourth embodiment.

  Hereinafter, four Examples 1 to 4 embodying a mode for carrying out the present invention will be described.

A first embodiment of the present invention will be described with reference to FIGS.
First, a schematic configuration of the entire system will be described with reference to FIG.

  The input shaft of the automatic transmission 12 is connected to the output shaft (crank shaft) of the engine 11. Although the internal configuration of the automatic transmission 12 is not shown, a torque converter that is rotationally driven by the output shaft of the engine 11, a transmission gear mechanism that is coupled to the output shaft (turbine shaft) of the torque converter, and the transmission gear mechanism A friction engagement device that switches a combination (gear ratio) of gears that transmit power from among a plurality of gears that constitute the motor, and a hydraulic control circuit that switches the operation state of the friction engagement device with hydraulic pressure are included in the automatic transmission 12. Is provided. The hydraulic control circuit includes a hydraulic control valve 13 for controlling the hydraulic pressure supplied to each friction engagement element such as a clutch and a brake constituting the friction engagement device, and a motor 14 in conjunction with a shift operation of the shift lever. A spool valve 16 of a range switching mechanism 15 (see FIG. 2) to be switched is provided. The spool valve 16 functions as a so-called manual valve that is switched in conjunction with the shift operation of the shift lever.

  The shift control ECU 17 that controls the shift operation of the automatic transmission 12 detects the hydraulic pressure supplied to the friction engagement device by the hydraulic sensor 18, and based on the detected hydraulic pressure and the output signal of the vehicle speed sensor 19, the hydraulic control circuit The gear position is switched to the target gear position by controlling the hydraulic pressure supplied to each friction engagement element by controlling the opening / closing operation of each hydraulic pressure control valve 13.

  On the other hand, the range switching ECU 20 (range switching control means) drives and controls the motor 14 based on the output signal of the shift range detection device 21 that detects the shift range selected by operating a shift lever (not shown). The switching operation of the spool valve 16 of the range switching mechanism 15 is controlled according to the driver's range switching operation. The range switching ECU 20, the shift control ECU 17, the engine ECU 22 that controls the operating state of the engine 11, and the meter ECU 42 that controls the display of the display device 41 are connected to the power line 47 from the battery 23 (power source) mounted on the vehicle. Electric power is supplied through. Also, the ECUs 20, 17, 22, and 42 transmit and receive necessary information such as throttle opening and ignition timing to each other through the communication line 24. The engine ECU 22 is connected to various sensors (for example, a crank angle sensor 48 that detects the engine rotation speed) that detect the operating state of the engine 11.

  The engine 11 is provided with a starter 43 that rotationally drives (cranks) the crankshaft at start-up. When the driver operates the ignition key switch 44 from the ON position (IG position) to the START position, the engine ECU 22 starts a starter relay 45. Is turned on and the starter 43 is energized from the battery 23, the starter 43 rotates and the engine 11 is cranked and started, and then the driver returns the ignition key switch 44 from the START position to the ON position. 45 is turned off, and energization to the starter 43 is stopped.

Next, the configuration of the range switching mechanism 15 will be described with reference to FIG.
The range switching mechanism 15 is for switching the shift range of the automatic transmission 12 to, for example, a parking range (P range), a reverse range (R range), a neutral range (N range), and a drive range (D range). . The motor 14 serving as a drive source for the range switching mechanism 15 is constituted by a synchronous motor such as a switched reluctance motor (SR motor), for example, and includes a speed reduction mechanism 52 (see FIG. 3). An output shaft sensor 46 that detects the rotational position of the output shaft 25 that is fitted and connected to the output shaft sensor 46 is provided, and the actual shift range is detected based on the output signal of the output shaft sensor 46.

  A detent lever 28 for switching the spool valve 16 of the hydraulic control circuit of the automatic transmission 12 is fixed to the output shaft 25 of the motor 14. An L-shaped parking rod 29 is fixed to the detent lever 28, and a cone 30 provided at the tip of the parking rod 29 is in contact with the lock lever 31. The lock lever 31 is moved up and down around the shaft 32 according to the position of the cone 30 to lock / unlock the parking gear 33. The parking gear 33 is provided on the output shaft of the automatic transmission 12, and when the parking gear 33 is locked by the lock lever 31, the driving wheel of the vehicle is held in a stopped state (parking state).

  Further, the spool 34 of the spool valve 16 is connected to the detent lever 28, and the operation amount of the spool valve 16 (operation position of the spool 34) is switched by rotating the detent lever 28 by the output shaft 25 of the motor 14. Thus, the shift range of the automatic transmission 12 is switched to any one of the P range, the R range, the N range, the D range, and the like. The detent lever 28 is formed with a plurality of recesses 35 for holding the spool 34 of the spool valve 16 at positions corresponding to the above ranges.

  On the other hand, a detent spring 36 for holding the detent lever 28 at a position corresponding to each range is fixed to the spool valve 16, and an engaging portion 37 provided at the tip of the detent spring 36 is used for the target range of the detent lever 28. By fitting in the recess 35, the detent lever 28 is held at the rotation angle of the target range, and the position of the spool 34 of the spool valve 16 is held at the position of the target range. The detent lever 28 and the detent spring 36 constitute a detent mechanism 38 (moderation mechanism) for engaging and holding the operation amount of the spool valve 16 (operation position of the spool 34) at the position of each range.

  In the P range, the parking rod 29 moves in a direction approaching the lock lever 31, the thick part of the cone 30 pushes up the lock lever 31, and the convex portion 31 a of the lock lever 31 fits into the parking gear 33. The gear 33 is locked, whereby the output shaft (drive wheel) of the automatic transmission 12 is held in the locked state (parking state).

  On the other hand, in ranges other than the P range, the parking rod 29 moves in a direction away from the lock lever 31, the thick part of the cone 30 comes out of the lock lever 31, and the lock lever 31 is lowered. The convex portion 31a is disengaged from the parking gear 33, the parking gear 33 is unlocked, and the output shaft of the automatic transmission 12 is held in a rotatable state (running state).

  The motor 14 is provided with an encoder 53 (see FIG. 3) for detecting the rotational position of the rotor. The encoder 53 is composed of, for example, a magnetic rotary encoder, and is configured to output A-phase and B-phase pulse signals having different phases to the range switching ECU 20 in synchronization with the rotation of the rotor of the motor 14. Yes. The range switching ECU 20 counts both rising / falling edges of the A-phase signal and B-phase signal output from the encoder 53, and the motor drive circuit 54 determines the energized phase of the motor 14 according to the encoder count value. The motor 14 is rotationally driven by switching in a predetermined order.

  At this time, the rotation direction of the rotor is determined based on the generation order of the A-phase signal and the B-phase signal, the encoder count value is counted up in the forward rotation direction (P range → D range rotation direction), and the reverse rotation direction (D range) (→ P range rotation direction) The encoder count value is counted down. As a result, the correspondence relationship between the encoder count value and the rotational position of the motor 14 is maintained even if the motor 14 rotates in either the forward rotation or the reverse rotation. However, the rotational position of the motor 14 can be detected by the encoder count value, and the motor 14 can be rotationally driven by energizing the winding of the phase corresponding to the rotational position.

As described above, in the P range, the cone 30 at the tip of the parking rod 29 pushes up the lock lever 31, and the convex portion 31a of the lock lever 31 is fitted into the parking gear 33 so that the parking gear 33 is locked. ing. As shown in FIG. 4, when the vehicle is parked on a slope, a torque T1 determined by the vehicle weight W, the slope θ of the slope, and the radius r of the tire acts on the tire.
T1 = F × r
= (W × sin θ) × r
The tire torque T1 increases as the slope θ of the slope increases.

  As shown in FIG. 5, the tire torque T 1 is transmitted to the propeller shaft 57 via the axle 55 and the differential gear 56, and the torque T 2 of the propeller shaft 57 is transmitted to the parking gear 33 via the output shaft of the automatic transmission 12. However, since the parking gear 33 is locked by the convex portion 31 a of the lock lever 31, the lock lever 31 is pressed against the cone 30 of the parking rod 29 by the reaction force. For this reason, a considerably large torque is required for the P-range releasing operation for extracting the parking rod 33 from the lower side of the lock lever 31.

  As shown in FIG. 6, when the range is switched from the P range, a large torque is required to pull out the parking rod 33 from the lower side of the lock lever 31 first, and the engaging portion 37 of the detent spring 36 is used as the detent lever. Torque for climbing over the mountain between the 28 recesses 35 is also required. The torque required for the P range release operation is much larger than the torque required for the range switching operation from a range other than the P range (see FIGS. 6 and 7).

  In general, the torque of the motor 14 changes due to fluctuations in power supply voltage (battery voltage) and fluctuations in winding resistance due to motor temperature. Further, the torque required for the P range release operation varies depending on the manufacturing variation of the vehicle and changes with time, and also varies depending on the slope of the slope and the vehicle weight (number of passengers). Therefore, conventionally, it is necessary to mount a high-torque motor 14 that can secure the required torque even under the most severe conditions in consideration of these various fluctuation factors, and the motor 14 is increased in size and cost accordingly. There were drawbacks such as.

  Accordingly, in the first embodiment, the range switching mechanism 15 is provided with a detent mechanism 38 that engages and holds the shift range with each range by a spring force, and the shift range is changed from the P range to the target range. When the P range is released, the detent mechanism 38 is urged in the range switching direction by slightly rotating the motor 14 slightly in the direction opposite to the range switching direction, as shown in FIGS. 8 (a) and 8 (b). 8 (c) and 8 (d), the motor 14 is moved in the range switching direction while the elastic force stored in the detent mechanism 38 is applied in the range switching direction. , The kinetic energy in the range switching direction is increased, and the shift range is switched from the P range to the target range.

  Once the motor reverse operation is performed during the P range release operation, elastic energy E1 is accumulated in the detent mechanism 38 as shown in FIG. If the elastic energy E1 is larger than the energy E2 required to extract the parking rod 33 from the lock lever 31, the shift range is switched from the P range to the target range using the elastic energy E1 stored in the detent mechanism 38. Can do. As a result, even if the torque of the motor 14 is smaller than that of the prior art, the P range release operation can be performed, and the motor 14 can be reduced in size and cost.

  The elastic energy E1 accumulated in the detent mechanism 38 by the motor reverse operation increases as the amount of reverse rotation of the motor 14 increases. The amount of reverse rotation of the motor 14 is determined by the engagement portion 37 of the detent spring 36 and the P range side wall of the detent lever 28. However, if the motor 14 is rotated reversely until it reaches the rotation limit position, the load applied to the detent mechanism 38 becomes too large, and the durability may be reduced. Therefore, it is desirable to set the reverse rotation amount of the motor 14 in a range that does not hit the rotation limit position.

  The control of the P range release operation of the first embodiment described above is executed by the range switching ECU 20 according to the P range release operation control program of FIG. This program is repeatedly executed at a predetermined period during the power-on period of the range switching ECU 20, and serves as a range switching control means in the claims.

  When the program is started, first, at step 101, it is determined whether or not a range switching operation has been performed. If the range switching operation has not been performed, the program is terminated as it is.

  On the other hand, if it is determined in step 101 that the range switching operation has been performed, the process proceeds to step 102, where it is determined whether or not the current range is the P range. In step 103, the motor 14 is once rotated slightly in the direction opposite to the range switching direction to store the elastic force in the detent mechanism 38. After this, the routine proceeds to step 104 where the motor 14 is rotated in the range switching direction while the elastic force stored in the detent mechanism 38 is applied in the range switching direction, thereby increasing the kinetic energy in the range switching direction and increasing the shift range. Switch from P range to target range.

  On the other hand, if it is determined in step 102 that it is not in the P range, the process proceeds to step 104 without performing the process of step 103 (motor reverse rotation operation), and the motor 14 is immediately rotated in the range switching direction and shifted. Switch the range from the P range to the target range.

  According to the first embodiment described above, when the shift range is switched from the P range to another range, the motor 14 is once rotated slightly in the direction opposite to the range switching direction to cause the detent mechanism 38 to switch the range switching direction. After the elastic force to be biased is stored, the motor 14 is rotated in the range switching direction while the elastic force stored in the detent mechanism 38 is applied in the range switching direction, thereby increasing the kinetic energy in the range switching direction. Since the shift range is switched from the P range to the target range, the P range release operation can be performed even if the torque of the motor 14 is smaller than the conventional range, and the motor 14 can be reduced in size and cost. it can.

  Incidentally, the torque of the motor 14 changes due to fluctuations in the power supply voltage (battery voltage) and fluctuations in the winding resistance value due to motor temperature. Further, the torque required for the P range release operation varies depending on the slope of the slope where the vehicle is parked. In the present invention, the motor reverse rotation operation may be performed every time during the P range release operation, but the time required for the range switching operation from the P range is increased accordingly.

In consideration of these points, in Embodiments 2 to 4 of the present invention, considering the power supply voltage (battery voltage), the motor temperature, and the slope of the parked slope, only the torque of the motor 14 is necessary for the P range release operation. The motor reverse operation is performed when a sufficient torque cannot be secured, and when the torque necessary for the P range release operation can be secured only by the torque of the motor 14, the motor is immediately switched from the P range to the target range without performing the motor reverse operation. Yes.
Hereinafter, Examples 2 to 4 will be described.

  The second embodiment of the present invention includes power supply voltage detection means (for example, a voltage sensor) that detects or estimates a power supply voltage (battery voltage) supplied to the motor 14, and executes the P-range release operation control program of FIG. When the power supply voltage is equal to or higher than the predetermined voltage during the P range release operation, it is determined that the torque necessary for the P range release operation is secured, and the P range is immediately switched to the target range without performing the motor reverse rotation operation. ing.

  The P-range release operation control program of FIG. 11 is merely the addition of step 102a after step 102 of the P-range release operation control program of FIG. 10 described in the first embodiment, and the processing of other steps is the same. .

  In the P range release operation control program of FIG. 11, when a range switching operation from the P range is performed, “Yes” is determined in steps 101 and 102 and the process proceeds to step 102 a to check whether the power supply voltage is equal to or lower than a predetermined voltage. Only when it is determined that the power supply voltage is equal to or lower than the predetermined voltage, the process proceeds to step 103, the motor reverse rotation operation is performed, and the elastic force that biases the detent mechanism 38 in the range switching direction is stored. In step 104, the motor 14 is rotated in the range switching direction to switch the shift range from the P range to the target range.

  On the other hand, if it is determined in step 102a that the power supply voltage is higher than the predetermined voltage, it is determined that the torque necessary for the P-range release operation is secured, and the process of step 103 (motor reverse operation) In step 104, the motor 14 is immediately rotated in the range switching direction to switch the shift range from the P range to the target range.

  According to the second embodiment described above, when the power supply voltage is a normal voltage equal to or higher than a predetermined voltage, the motor 14 is immediately rotated in the range switching direction without performing the motor reverse operation, so that the shift range is changed from the P range to the target range. Since switching is performed, the range switching operation from the P range can be performed with good response.

  The third embodiment of the present invention includes a slope parking determination unit that determines whether or not the vehicle is parked on a slope, and executes the P range release operation control program shown in FIG. When it is determined that the vehicle is not parked (parking on a flat road surface), it is determined that the torque necessary for the P range release operation is secured, and the target range is immediately determined from the P range without performing the motor reverse rotation operation. To switch to. Here, the slope parking determination means detects or estimates the slope of the parking road surface (tilt angle in the front-rear direction of the vehicle), for example, and determines that the parking road is parked when the slope of the parking road surface is equal to or greater than a predetermined value. To do.

  The P-range release operation control program in FIG. 12 is simply the addition of step 102b after step 102 of the P-range release operation control program in FIG. 10 described in the first embodiment, and the processing in the other steps is the same. .

  In the P range release operation control program of FIG. 12, when a range switching operation from the P range is performed, “Yes” is determined in Steps 101 and 102, and the process proceeds to Step 102b. Is determined to be equal to or greater than a predetermined value, and if it is determined that the slope of the parking road surface is equal to or greater than the predetermined value, it is determined that the road is parked on a slope, and the process proceeds to step 103 to perform a motor reverse rotation operation. Then, after storing the elastic force for energizing the detent mechanism 38 in the range switching direction, the process proceeds to step 104 where the motor 14 is rotated in the range switching direction to switch the shift range from the P range to the target range.

  On the other hand, if it is determined in step 102b that the slope of the parking road surface is less than the predetermined value (not slope parking), it is determined that the torque necessary for the P range release operation is secured, and step 103 Without performing the processing (motor reverse rotation operation), the routine proceeds to step 104, where the motor 14 is immediately rotated in the range switching direction to switch the shift range from the P range to the target range.

  According to the second embodiment described above, if the slope of the parking road surface is determined to be less than a predetermined value (not slope parking), the motor 14 is immediately rotated in the range switching direction without performing the motor reverse rotation operation. Since the shift range is switched from the P range to the target range, the range switching operation from the P range can be performed with good response.

  In the fourth embodiment of the present invention, the power supply voltage detection means for detecting or estimating the power supply voltage (battery voltage) supplied to the motor 14, the slope parking judgment means for judging whether or not the slope parking is performed, and the temperature of the motor 14 are set. Motor temperature detecting means for detecting or estimating, and by executing the P range release operation control program of FIG. 13, if any one of the following three conditions (1) to (3) is satisfied, P When the motor reverse operation is performed once during the range release operation, the motor 14 is rotated in the range switching direction, and if none of the three conditions (1) to (3) is satisfied, the motor torque required for the P range release operation Therefore, it is immediately switched from the P range to the target range without performing the motor reverse rotation operation.

(1) The power supply voltage is below the specified voltage
(2) Parking on a hill (the slope of the parking road surface must be above a specified value)
(3) The motor temperature is higher than the specified temperature

  Here, for example, the motor temperature detecting means attaches a temperature sensor to the motor 14 to detect the motor temperature, or detects the resistance value of the winding of the motor 14 and determines the motor temperature (winding) from the resistance value of the winding. Temperature) may be estimated.

  The P-range release operation control program of FIG. 13 is simply the addition of steps 102a to 102c after step 102 of the P-range release operation control program of FIG. 10 described in the first embodiment, and the processing of the other steps is the same. It is.

  In the P range release operation control program of FIG. 12, when a range switching operation from the P range is performed, “Yes” is determined in steps 101 and 102, and the process proceeds to steps 102a to 102c. (1) Power supply voltage Is equal to or lower than a predetermined voltage, (2) parking on a slope (the slope of the parking road surface is equal to or higher than a predetermined value), and (3) “Yes” in any of steps 102a to 102c if the motor temperature is higher than a predetermined temperature. After the determination, the routine proceeds to step 103, the motor reverse rotation operation is performed and the detent mechanism 38 stores the elastic force for urging in the range switching direction, and then the routine proceeds to step 104 where the motor 14 is rotated in the range switching direction to shift range. Is switched from the P range to the target range.

  If none of the above three conditions (1) to (3) is satisfied, it is determined as “No” in steps 102a to 102c, and it is determined that the torque necessary for the P range release operation is secured. The process proceeds to step 104 without performing the process of step 103 (motor reverse rotation operation), and the motor 14 is immediately rotated in the range switching direction to switch the shift range from the P range to the target range.

  In the P range release operation control program of FIG. 13, any one of steps 102a to 102c may be omitted. Further, steps 102a and 102b may be omitted and only step 102c may be used.

  Further, during the motor reverse rotation operation, the reverse rotation amount of the motor 14 (energy storage amount of the detent mechanism 38) may be changed according to the power supply voltage, the parking road surface gradient, and the motor temperature. For example, the lower the power supply voltage, the larger the reverse rotation amount of the motor 14, the larger the parking road gradient, the larger the reverse rotation amount of the motor 14, or the higher the motor temperature, the larger the reverse rotation amount of the motor 14. May be.

  In consideration of the presence of backlash in the range switching mechanism 15 (backlash in the rotation transmission system), during the P range release operation, the motor 14 is once reversed in the range switching direction within the backlash of the range switching mechanism 15. After slightly rotating in the direction, the backlash of the range switching mechanism 15 is reduced, and then the motor 14 is rotated in the range switching direction, thereby increasing the kinetic energy in the range switching direction and changing the shift range from the P range to the target range. You may make it switch to. In this way, even when the motor 14 is slightly rotated in the direction opposite to the range switching direction within the range of the backlash of the range switching mechanism 15 during the P range release operation, the motor due to the backlash of the range switching mechanism 15 It is possible to increase the kinetic energy in the range switching direction by creating an idle running section and accelerating the motor 14. Thereby, even if the torque of the motor 14 is smaller than the conventional one, the P range release operation can be performed reliably, and the motor 14 can be reduced in size and cost.

  In addition, the present invention can be implemented with various modifications within a range not departing from the gist, such as appropriately changing the configuration of the range switching mechanism 15.

  DESCRIPTION OF SYMBOLS 11 ... Engine, 12 ... Automatic transmission, 13 ... Hydraulic control valve, 14 ... Motor, 15 ... Range switching mechanism, 16 ... Spool valve, 17 ... Shift control ECU, 20 ... Range switching ECU (range switching control means), 22 ... Engine ECU, 23 ... Battery, 28 ... Detent lever, 29 ... Parking rod, 30 ... Cone, 31 ... Lock lever, 33 ... Parking gear, 35 ... Recess, 36 ... Detent spring, 37 ... Engagement part, 38 ... Detent mechanism, 53 ... Encoder

Claims (5)

A range switching mechanism that switches the shift range of the automatic transmission between a plurality of ranges including a parking range using a motor as a drive source, and the motor is driven and controlled according to the driver's range switching operation to switch the shift range to the target range. In a range switching control device comprising a range switching control means,
The range switching control means performs a motor reverse operation for rotating the motor a little in the direction opposite to the range switching direction at the time of the parking range release operation for switching the shift range from the parking range to the target range. A range switching control device characterized in that, by rotating in the range switching direction, the kinetic energy in the range switching direction is increased to switch the shift range from the parking range to the target range. A range switching mechanism that switches the shift range of the automatic transmission between a plurality of ranges including a parking range using a motor as a drive source, and the motor is driven and controlled according to the driver's range switching operation to switch the shift range to the target range. In a range switching control device comprising a range switching control means,
The range switching mechanism includes a detent mechanism that engages and holds a shift range in each range with a spring force,
The range switching control means attaches the detent mechanism to the range switching direction by rotating the motor slightly in the direction opposite to the range switching direction during the parking range release operation for switching the shift range from the parking range to the target range. After performing the reverse rotation operation of the motor that stores the elastic force, the kinetic energy in the range switching direction is reduced by rotating the motor in the range switching direction while applying the elastic force stored in the detent mechanism in the range switching direction. A range switching control device characterized in that the shift range is switched from a parking range to a target range by increasing. Power supply voltage detection means for detecting or estimating the power supply voltage supplied to the motor,
The range switching control means switches from the parking range to the target range without performing the motor reverse rotation operation when the power supply voltage detected or estimated by the power supply voltage detecting means is higher than a predetermined voltage during the parking range release operation. The range switching control device according to claim 1 or 2. Slope parking judging means for judging whether or not it is slope parking,
The range switching control means switches from the parking range to the target range without performing the motor reverse rotation operation when the slope parking judging means determines that the parking is not slope parking during the parking range release operation. The range switching control apparatus in any one of thru | or 3. Motor temperature detecting means for detecting or estimating the temperature of the motor;
The range switching control means switches from the parking range to the target range without performing the motor reverse operation when the motor temperature detected or estimated by the motor temperature detecting means during the parking range releasing operation is equal to or lower than a predetermined temperature. The range switching control device according to any one of claims 1 to 4.

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