JP2005114103A - Oil pump controller for stepless speed changer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To hold a fuel consumption performance in a good state by switching a charging output of operating fluid from a pump to a stepless speed changer according to an operating situation of a vehicle. <P>SOLUTION: An oil pump controller for the stepless speed changer includes a step of reading signals from various type sensors (step S1), a step of confirming whether an engine speed Ne is a high revolution (Neref) or not (step S2), and a step of suppressing an amount of circulation of the operating fluid to about a half at a low speed operating time (step S10) by switching the operating fluid discharged from the pump by a directional control valve in a state that conditions in which the vehicle is completely stopped (step S5) when the engine speed Ne is a low revolution, are satisfied, which is idle running rotational frequency (step S7) in which a throttle opening is a fully closed state and a braking operation is performed (step S6), an oil temperature T of the operating fluid is Tref or lower (step S8), etc. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an oil pump control device for a continuously variable transmission that, for example, controls a continuously variable transmission that continuously changes the output shaft rotational speed of an engine in a vehicle and transmits it to a wheel shaft by hydraulic oil pressure.

  2. Description of the Related Art A continuously variable transmission that continuously changes the output speed of an engine output shaft and transmits it to a wheel shaft in a vehicle has been developed and put into practical use. By using a continuously variable transmission, it is possible to achieve a smooth shift and to select an appropriate engine speed according to the driving situation, thereby reducing fuel consumption.

  The continuously variable transmission is composed of a driving pulley provided on the output shaft side of the engine and a driven pulley that is provided on the wheel shaft side and is driven to rotate via a driving force transmission belt. The driving pulley and the driven pulley are respectively displaced along a fixed pulley integrally fixed to the driving shaft and the wheel shaft, and an axial direction of the driving shaft and the wheel shaft, so that a separation distance from the fixed pulley is increased. A movable movable pulley is configured as a pair, and a driving force transmission belt is interposed between the fixed pulley and the movable pulley in the driving pulley and the driven pulley.

  Then, by moving the movable pulley toward and away from the fixed pulley via the hydraulic pressure of the hydraulic oil supplied from the oil pump, the driving pulley is interposed between the driving and driven pulleys. The driving force transmitted from the engine output shaft is steplessly changed and transmitted to the wheel shaft.

  This oil pump is desired to always maintain a predetermined discharge amount from the low rotation region to the high rotation region of the engine. For this reason, the oil pump driven through the engine output shaft has substantially the same rotational speed as the torque converter of the continuously variable transmission or the rotational speed of the engine, and is operated from the oil pump at the time of shifting through the correction means. The oil discharge amount is increased (for example, see Patent Document 1).

JP-A-2-266153

  By the way, in the prior art according to Patent Document 1 described above, since the amount of hydraulic oil discharged to the continuously variable transmission is determined by the torque converter of the continuously variable transmission or the rotational speed of the engine, the rotational speed of the engine or the like is high. Sometimes the discharge rate from the oil pump increases, and at low speed, the discharge rate from the oil pump decreases.

  For this reason, when the engine is running at a low speed (for example, when the vehicle is traveling at a low speed), the amount of discharge from the oil pump is insufficient with respect to the required amount of hydraulic oil in the continuously variable transmission. The discharge amount is increased so that the discharge amount of the hydraulic oil from the engine is substantially the same as that at the time of high rotation.

  For example, when the vehicle is stopped due to a traffic jam, waiting for a signal, etc., the engine mounted on the vehicle is in an idling state where the number of revolutions is low. Therefore, in the continuously variable transmission, when a power interrupting mechanism is not provided after the continuously variable transmission mechanism, the continuously variable transmission is not operating at all, so the hydraulic oil discharged to the continuously variable transmission is not There is no need to increase the discharge amount. In other words, when the engine is in an idling state, the driving pulley and the driven pulley in the continuously variable transmission are not operating, and the consumption of hydraulic oil is relatively low because it is not necessary to lubricate the wheel shaft. It is in.

  However, actually, even when the vehicle is stopped and the engine is idling, the amount of hydraulic oil supplied from the oil pump to the continuously variable transmission is large, so that the friction generated in the oil pump is large. At the same time, fuel consumption increases and fuel consumption deteriorates.

  The present invention has been made in consideration of such problems, and it is possible to keep fuel consumption performance in a good state by switching the discharge amount of hydraulic oil from the pump to the continuously variable transmission. An object of the present invention is to provide an oil pump control device for a step transmission.

In order to achieve the above object, the present invention provides an oil pump control device for a continuously variable transmission that continuously shifts an output shaft and a wheel shaft of an engine in a vehicle via hydraulic oil pressure.
The continuously variable transmission oil pump control device includes a variable displacement pump that changes a discharge amount of hydraulic oil supplied to the continuously variable transmission according to an operation state of the vehicle,
When the engine is in an idling state, the amount of hydraulic oil supplied from the variable displacement pump to the continuously variable transmission is hydraulic oil that is discharged when the vehicle is running when the vehicle is stopped. The discharge amount is set to be smaller than that of the discharge amount (the invention according to claim 1).

  As described above, when the engine is idling while the vehicle is stopped, the discharge amount of hydraulic oil supplied from the variable displacement pump to the continuously variable transmission is compared with that when the vehicle is running. Is decreasing. Accordingly, even when the vehicle frequently stops due to a signal waiting or traffic jam, the friction loss in the variable displacement pump is reduced by suppressing the discharge amount of hydraulic fluid from the variable displacement pump, and accordingly Thus, fuel consumption can be reduced and fuel consumption can be improved.

A driving pulley provided on the output shaft side of the engine; a driven pulley provided on the wheel shaft side; and a driving force transmission belt interposed between the driving pulley and the driven pulley. The movable pulley is displaced by a cylinder mechanism to adjust the groove width of the driving pulley, and the movable pulley in the driven pulley is displaced by a cylinder mechanism to adjust the groove width of the driven pulley, and the engine in the driving pulley is adjusted. A belt-type continuously variable transmission equipped with a starting mechanism on the output shaft side,
In the oil pump control device for continuously variable transmission, the hydraulic oil is supplied to the cylinder mechanism in the drive pulley and the driven pulley, respectively, and the output shaft and the wheel shaft are continuously shifted.
When the engine is in an idling state, the amount of hydraulic oil supplied from the variable displacement pump to the continuously variable transmission is hydraulic oil that is discharged when the vehicle is running when the vehicle is stopped. The discharge amount is set to be smaller than that of the discharge amount (the invention according to claim 2).

  As described above, when the engine is idling while the vehicle is stopped, the vehicle travels the discharge amount of the hydraulic oil supplied from the variable displacement pump to the cylinder mechanism in the drive pulley and the driven pulley. It is reduced compared to the case. Therefore, even when the vehicle frequently stops due to a signal waiting, traffic jams, etc., the friction loss in the variable displacement pump can be reduced by suppressing the amount of hydraulic oil discharged from the variable displacement pump to the drive pulley and the driven pulley. In addition to reducing the fuel consumption, the fuel consumption can be reduced.

  According to the present invention, the following effects can be obtained.

  That is, when the engine is idling while the vehicle is stopped, the amount of hydraulic oil supplied from the variable displacement pump to the continuously variable transmission is reduced compared to when the vehicle is running. Therefore, the friction loss in the variable displacement pump is reduced, and the fuel consumption is reduced accordingly, so that the fuel consumption performance is kept in a good state.

  A preferred embodiment of an oil pump control device for a continuously variable transmission according to the present invention will be described in detail below with reference to the accompanying drawings.

  In FIG. 1, reference numeral 20 denotes a continuously variable transmission control device to which an oil pump control device for a continuously variable transmission (hereinafter simply referred to as a pump system) according to an embodiment of the present invention is applied.

  The continuously variable transmission control device 20 continuously changes the rotational speed of the output shaft 22a of the engine 22 in the vehicle and transmits it to the wheel shaft 24 (hereinafter referred to as CVT (Continuously Variable Transmission)) 26. Is for controlling. The continuously variable transmission control device 20 controls the engine 22 and performs auto-cruise in accordance with an instruction from the driver of the vehicle, a CVT control unit 32 that controls the gear ratio of the CVT 26, the main controller 30, Various sensors (to be described later) connected to the CVT control unit 32.

  Next, the CVT 26 and the drive mechanism of the vehicle on which the CVT 26 is mounted will be described with reference to FIG.

  A throttle valve 38 is disposed in the intake pipe 36 connected to the engine 22, and the throttle valve 38 is linked to the operation of an accelerator pedal (not shown) in the driver's seat and is controlled by the main controller 30 and the vacuum valve 40. Open and close.

  An output shaft 22 a of the engine 22 is connected to the torque converter 42. In the torque converter 42, the torque converter cover 42a connected to the output shaft 22a rotates the pump impeller 42b and rotates the turbine impeller 42c relative to the torque converter shaft 44 through oil filled therein.

  In the torque converter 42, the rotation of the output shaft 22a can be directly transmitted to the torque converter shaft 44 by engaging the torque converter cover 42a and the torque converter shaft 44 by the lock-up clutch 42e.

  The torque converter shaft 44 is connected to a planetary gear type forward / reverse switching mechanism 46 of the CVT 26, and the planetary gear type forward / backward switching mechanism 46 is integrally connected to the torque converter shaft 44, and the input rotation portion. 46a and the forward clutch 46b which connects the input shaft 48 of CVT26, and the ring gear 46c comprised integrally with the input rotation part 46a. The planetary gear type forward / reverse switching mechanism 46 includes a sun gear 46d provided on the input shaft 48 and a plurality of planetary gears 46e meshing with the ring gear 46c, a carrier 46f for rotating and supporting the planetary gear 46e, and the carrier A reverse clutch 46g for engaging the outer periphery of 46f with the housing.

  The CVT 26 includes the planetary gear type forward / reverse switching mechanism 46, a drive pulley 50 supported by the input shaft 48, and a driven pulley 54 that rotates following a rotation of the drive pulley 50 via a metal belt 52. And an output shaft 58 that transmits the rotation of the driven pulley 54 to the intermediate shaft 56.

  The drive pulley 50 includes a fixed pulley half 50a fixed to the input shaft 48 and a movable pulley half 50b slidable in the axial direction by hydraulic pressure acting on the hydraulic oil chamber 60. The groove width of the groove 50c of the drive pulley 50 can be changed by the sliding position of the body 50b.

  Similarly, the driven pulley 54 includes a fixed pulley half 54 a fixed to the output shaft 58 and a movable pulley half 54 b slidable in the axial direction by the hydraulic pressure acting on the hydraulic oil chamber 62. The groove width of the groove 54c of the driven pulley 54 can be changed by the sliding position of the side pulley half 54b.

  The pump system 64 is connected to a tank 65 in which a predetermined amount of hydraulic oil supplied to the drive pulley 50 and the driven pulley 54 is stored, and the tank 65 and the first oil passage 66 to connect the hydraulic oil to the drive pulley. 50 and a pump (variable displacement pump) 68 that discharges toward the driven pulley 54, and a first discharge port 70 a (see FIG. 2) on one side of the pump 68 and a first oil passage 72 that is connected via a first oil passage 72. A control valve 74 is connected to the second discharge port 70b (see FIG. 2) on the other side of the pump 68 via a third oil passage 76, and the flow state of the hydraulic oil P2 flowing through the fourth oil passage 78 is determined. A switching valve 80 for switching, a second control valve 82 that communicates with the hydraulic oil chamber 60 (see FIG. 1) of the drive pulley 50 and is supplied with hydraulic oil from the first control valve 74, and an operation of the driven pulley 54 Communicates with the chamber 62 (see FIG. 1), and a third control valve 84 the hydraulic oil supplied from the first control valve 74 as well.

  The pump 68 is composed of, for example, a vane pump, and first and second introduction ports 86 a and 86 b through which hydraulic oil is introduced from the tank 65 via the first oil passage 66, and first and second discharges the hydraulic oil. Discharge ports 70a and 70b (see FIG. 2). As shown in FIG. 2, the hydraulic oil P <b> 1 introduced into the pump 68 from the first introduction port 86 a is discharged from the first discharge port 70 a and passes through the second oil passage 72 to the first control valve. The hydraulic oil P2 introduced into the inside of the pump 68 and introduced into the pump 68 from the second introduction port 86b is discharged from the second discharge port 70b, and the second of the switching valve 80 via the third oil passage 76. 2 port 88b is supplied.

  The flow rate A of the hydraulic oil P1 discharged from the first discharge port 70a of the pump 68 to the second oil passage 72, and the switching valve 80 via the third oil passage 76 from the second discharge port 70b of the pump 68. And the flow rate B of the hydraulic oil P2 to be supplied are set to be substantially equal (A = B).

  As shown in FIGS. 3 and 4, the switching valve 80 includes annular first to third ports 88 a, 88 b, 88 c that are spaced apart from each other by a predetermined distance along the axial direction along the outer peripheral surface of the body 87. Is formed. A fourth oil passage 78 connected to the first branch portion 89 (see FIG. 2) in the middle of the second oil passage 72 connecting the pump 68 and the first control valve 74 is connected to the first port 88a. ing. A third oil passage 76 connected to the second discharge port 70b of the pump 68 is connected to the second port 88b, and hydraulic oil P2 is supplied from the pump 68.

  The third port 88c is connected to the fifth oil passage 102 connected via the second branch portion 98 in the middle of the first oil passage 66 connecting the tank 65 and the pump 68.

  Further, inside the switching valve 80, a valve body 90 is provided so as to be displaceable along the axial direction, and a spring 92 for biasing the valve body 90 in the direction of arrow C is provided. A pilot port 96 connected to a control valve (not shown) via a conduit 94 is formed at one end of the switching valve 80, and is supplied from the pilot port 96 under the control action of the CVT control unit 32. The valve body 90 is displaced in the direction of arrow D against the elastic force of the spring 92 by the pilot pressure. That is, the third oil passage 76 connected to the second port 88b and the fourth oil passage 78 connected to the first port 88a under the displacement action along the axial direction of the valve body 90 are in communication / non-communication state. Is switched.

  A communication passage 100 formed in an annular shape along the outer peripheral surface of the valve body 90 is formed on the outer peripheral surface of the valve body 90, and the communication passage 100 has three ports, namely, first to third ports 88a to 88c. It is formed so that any two of them communicate. In other words, when the valve body 90 is displaced in the direction of arrow C, the first port 88a and the second port 88b communicate with each other via the communication path 100, and when the valve body 90 is displaced in the direction of arrow D. The second port 88b and the third port 88c communicate with each other through the communication path 100.

  Therefore, as shown in FIG. 3, when the valve body 90 is displaced in the direction of arrow C by the elastic force of the spring 92 and the third oil passage 76 and the fourth oil passage 78 are in communication, the pump 68 ( The hydraulic oil P2 discharged from the second discharge port 70b (see FIG. 2) of FIG. 2) is introduced from the third oil passage 76 into the switching valve 80 through the second port 88b, and the communication passage 100. Through the first port 88a to the fourth oil passage 78. As shown in FIG. 2, the hydraulic oil P <b> 2 supplied to the fourth oil passage 78 merges with the hydraulic oil P <b> 1 discharged from the first discharge port 70 a of the pump 68 in the first branch portion 89. Therefore, the flow amount of the hydraulic oil flowing through the second oil passage 72 increases (P1 + P2).

  At that time, the flow rate A of the hydraulic oil P1 discharged from the first discharge port 70a of the pump 68 and the second discharge port 70b of the pump 68 are discharged and supplied to the fourth oil passage 78 via the switching valve 80. Therefore, the flow rate of the hydraulic fluid (P1 + P2) increased by joining in the second oil passage 72 is approximately twice the flow rate (A + B).

  A check valve (not shown) is provided in the middle of the fourth oil passage 78 to block the flow of hydraulic oil from the first branch portion 89 side to the switching valve 80 side in the fourth oil passage 78. Therefore, the hydraulic oil discharged from the first discharge port 70 a of the pump 68 to the second oil passage 72 is prevented from flowing back to the switching valve 80 via the first branch portion 89.

  On the other hand, when the valve body 90 is displaced in the direction of the arrow D under the pressure action by the pilot pressure and the third oil passage 76 and the fourth oil passage 78 are not in communication with each other by the switching valve 80, FIG. When the valve body 90 is displaced in the direction of arrow D, the communication path 100 is displaced integrally with the valve body 90, and the communication path 100 communicates with the second and third ports 88b and 88c. It becomes.

  Therefore, the hydraulic oil P2 introduced from the third oil passage 76 to the second port 88b is led out from the third port 88c to the fifth oil passage 102 via the communication passage 100. And since the said 5th oil path 102 is connected with the 1st oil path 66 via the 2nd branch part 98, the hydraulic oil P2 supplied to the switching valve 80 via the said 3rd oil path 76 is The first oil passage 66 is joined via the fifth oil passage 102. In other words, since the fourth oil passage 78 and the communication passage 100 are not in communication in the switching valve 80, the fourth oil passage of the hydraulic oil P2 introduced into the switching valve 80 through the third oil passage 76. The supply to 78 is cut off.

  Therefore, in a state where the valve body 90 in the switching valve 80 is displaced in the direction of the arrow D under the pressure action by the pilot pressure, the third oil passage 76 and the fourth oil passage 78 are in a non-communication state. Under the switching action, the hydraulic oil P2 that has joined from the fourth oil passage 78 to the second oil passage 72 when the third and fourth oil passages 76 and 78 are in communication is not joined, and the second oil The flow rate of the hydraulic oil flowing through the passage 72 is about half (only A) as compared with the case where the third and fourth oil passages 76 and 78 are in communication.

  The first control valve 74 is supplied with hydraulic oil from the pump 68 via the second oil passage 72, and after being reduced to a desired pressure value, is guided to the sixth oil passage 106. The sixth oil passage 106 branches in two directions starting from the third branch portion 104 that branches in the middle, and one is connected to the second control valve 82 and the other is connected to the third control valve 84. ing. That is, the hydraulic oil derived from the first control valve 74 is supplied to the hydraulic oil chamber 60 of the drive pulley 50 and the hydraulic oil chamber 62 of the driven pulley 54 via the second and third control valves 84, respectively. .

  The second control valve 82 and the third control valve 84 can change the pressure of the hydraulic oil chambers 60 and 62 to a desired value under the control action of the CVT control unit 32. The hydraulic oil supplied to the hydraulic oil chamber 60 of the drive pulley 50 is supplied from the pump 68 via the second control valve 82 and the sixth oil passage 106a passing through the axial center of the input shaft 48. The hydraulic oil supplied to the hydraulic oil chamber 62 of the driven pulley 54 is supplied from the pump 68 through the third control valve 84 and the sixth oil passage 106 b passing through the axial center of the output shaft 58.

  Accordingly, the movable pulley halves 50b and 54b can be slid in the axial direction in conjunction with each other, and the widths of the grooves 50c and 54c can be continuously changed. Therefore, the ratio of the diameter around which the metal belt 52 is wound, that is, the transmission ratio can be changed steplessly. In FIG. 1, the drive pulley 50 and the driven pulley 54 have a state in which the upper half centered on each axis is in a gear ratio OD (Over Drive) and the lower half centered on each axis is in a low gear ratio state. This is shown schematically.

  The rotational speed of the input shaft 48 is steplessly changed by the CVT 26 and transmitted to the output shaft 58. The rotational speed of the output shaft 58 is decelerated by the intermediate shaft 56 and transmitted to the differential gear 110. The differential gear 110 has a function of absorbing a difference in rotational speed between the inner wheel and the outer wheel during curve traveling.

  Connected to the main controller 30 are a throttle opening sensor 112 that detects the throttle opening TH, which is the opening of the throttle valve 38, and a pressure sensor 114 that detects an absolute pressure PB downstream of the throttle valve 38. The main controller 30 includes a crank angle sensor 116 that detects the crank angle of the engine 22, a water temperature sensor 118 that detects the engine water temperature, a rotation speed sensor 120 that detects the engine rotation speed Ne, and the rotation of the torque converter shaft 44. A rotation speed sensor 122 that detects the number, a vehicle speed sensor 124 that detects the vehicle speed V, and an oil temperature sensor (not shown) that detects the oil temperature T of the hydraulic oil are connected. Although not shown, the vehicle speed sensor 124 includes four vehicle speed sensors for the left and right drive wheels 128 and the left and right driven wheels.

  The CVT control unit 32 is provided with a rotation speed sensor 129 for detecting the rotation speed of the input shaft 48 by teeth provided on the outer peripheral portion of the fixed pulley half body 50a, and an outer peripheral portion of the fixed pulley half body 54a. A rotation speed sensor 130 that detects the rotation speed of the output shaft 58 by teeth and a position switch 132 that outputs a signal indicating a shift range (D, N, P, etc.) selected by the driver are connected. The CVT control unit 32 is connected to a throttle opening sensor 112, a pressure sensor 114, a crank angle sensor 116, rotation speed sensors 120, 122, 130, a vehicle speed sensor 124, and an oil temperature sensor (not shown). Yes. Further, the main controller 30 and the CVT control unit 32 are connected by a communication line 134, and mutual communication such as data is possible.

  The continuously variable transmission control device 20 to which the oil pump control device for continuously variable transmission according to the embodiment of the present invention is applied is basically configured as described above. The effect will be described.

  First, when the vehicle is stopped while the engine 22 is idling while being shifted to a drive (D range, L range) which is a forward position or a reverse (R range) which is a reverse position by the driver, A procedure for controlling the discharge amount of the hydraulic oil from the pump 68 in the pump system 64 will be described in detail with reference to FIGS.

  First, in step S1 of FIG. 5, from the throttle opening sensor 112 (see FIG. 1), the rotational speed sensor 120 (see FIG. 1), the vehicle speed sensor 124 (see FIG. 1), the oil temperature sensor (not shown), and the like. Signals such as the throttle opening TH, the engine speed Ne, the vehicle speed V, and the hydraulic oil temperature T are read at that time.

  Next, in step S2, it is confirmed whether the engine speed Ne read by the speed sensor 120 is greater than Neref (for example, about 4700 to 5000 rpm). When the engine speed Ne is greater than Neref, the process proceeds to step S10, and when smaller than Neref, the process proceeds to step S3.

Next, in step S3, whether or not the shift range selected by the driver is shifted to a drive (D range) that is a forward position, a low range (L range), or a reverse (R range) that is a reverse position. Is confirmed based on the signal detected from the position switch 132 (see FIG. 1), and a predetermined time (for example, 1 second) has passed since the shift change operation for changing the shift range is completed. It is confirmed whether or not.

  When the selected shift range is drive (D range), low range (L range) or reverse (R range), and a predetermined time or more has elapsed since the completion of the shift change operation by the driver. In step S4, the selected shift range is a parking position (P range), a neutral (N range) or the like where the vehicle does not move forward or backward, or a shift change operation is performed. If at least one of the conditions is satisfied when the predetermined time has not elapsed since the completion of the operation such as immediately after completion or when the shift change operation is being performed, the process proceeds to step S9.

  Next, in step S4, the torque converter cover 42a (see FIG. 1) and the torque converter shaft 44 (see FIG. 1) are engaged with each other by the lock-up clutch 42e (see FIG. 1), or the torque converter cover It is confirmed whether the engagement state between 42a and the torque converter shaft 44 is an off state in which the engagement state is completely released. If the lock-up clutch 42e is on, the process proceeds to step S9, and if the lock-up clutch 42e is completely off, the process proceeds to step S5.

  In step S5, it is confirmed whether or not the vehicle speed V of the vehicle read by the vehicle speed sensor 124 is zero. If the vehicle speed is zero and the vehicle is stopped (V = 0), the process proceeds to step S6. If the vehicle speed V is slightly (V> 0), that is, if the vehicle is traveling, the process proceeds to step S9.

  Next, in step S6, it is confirmed whether the throttle opening TH read by the throttle opening sensor 112 (see FIG. 1) is in a fully closed state and whether a brake operation is being performed. When the throttle opening TH is in the fully closed state (TH = 0), that is, when the accelerator pedal is not operated by the driver, and when the brake operation is performed by the driver, the process proceeds to step S7, and the throttle If at least one of the opening degree TH is slight (TH> 0) or the brake is not operated, the process proceeds to step S9.

  Next, in step S7, it is determined whether or not the engine speed Ne read by the speed sensor 120 is within the preset idle speed setting range, and is within the idling speed setting range. If this is the case, the process proceeds to step S8, and if it is outside the set range of the idle speed, the process proceeds to step S9.

  Finally, in step S8, it is confirmed whether or not the oil temperature T of the hydraulic oil read by the oil temperature sensor is higher than Tref (for example, about 100 ° C.). When the oil temperature T of the hydraulic oil is higher than Tref (T> Tref), the process proceeds to step S9, and when it is lower than Tref (T <Tref), the process proceeds to step S10.

  In step S9 and step S10, the total discharge that maximizes the discharge amount of hydraulic fluid discharged from the pump 68, which will be described later, to the drive pulley 50 and the driven pulley 54, respectively, is substantially half the discharge amount. This processing in the flowchart shown in FIG. 5 is terminated.

  Next, the operation of the pump system 64 when performing full discharge by the pump 68 executed in step S9 will be described. It is assumed that the pilot pressure is urged in advance from a control valve (not shown) to the pilot port 96 of the switching valve 80 in the pump system 64 so that the valve body 90 is displaced in the direction of arrow D.

  First, based on the flowchart of FIG. 5, a control signal is output from the CVT control unit 32 to a control valve (not shown) connected to the pilot port 96 of the switching valve 80, and a pipe is connected to the pilot port 96 based on the control signal. The pilot pressure supplied via the path 94 is in a state where it is extinguished.

  As shown in FIG. 3, the hydraulic oil P2 discharged from the second discharge port 70b of the pump 68 is obtained by displacing the valve body 90 of the switching valve 80 in the direction of arrow C by the elastic force of the spring 92. Is introduced from the second port 88 b of the switching valve 80 via the third oil passage 76. Then, the hydraulic oil P2 flows to the first port 88a through the communication path 100, and passes through the fourth oil path 78 and the first branch portion 89 (see FIG. 1) from the first port 88a to the second oil path 72. (See FIG. 1).

  At this time, since the hydraulic oil P1 is discharged and circulated in advance from the first discharge port 70a of the pump 68 to the second oil passage 72, it is supplied from the fourth oil passage 78 to the second oil passage 72. The hydraulic oil P2 joined with the hydraulic oil P1 increases the flow rate of the hydraulic oil flowing through the second oil passage 72. Specifically, the flow rate A of the hydraulic oil P1 discharged from the first discharge port 70a of the pump 68 and the hydraulic oil P2 introduced from the switching valve 80 to the second oil path 72 through the fourth oil path 78 are as follows. Since each of the flow rates B is substantially equal (A = B), the flow rate is approximately twice that of the case where only the hydraulic oil P1 discharged from the first discharge port 70a of the pump 68 is circulating ( A + B).

  Then, the hydraulic oil P1 + P2 is introduced into the first control valve 74 through the second oil passage 72, adjusted to a predetermined pressure by the first control valve 74, and then passed through the sixth oil passage 106. Supplyed to the second and third control valves 82, 84.

  The hydraulic oil P1 + P2 is regulated to a predetermined pressure under the action of pilot pressure supplied to the second and third control valves 82 and 84, respectively, and the drive pulley 50 is passed through the sixth oil passages 106a and 106b. And the hydraulic oil chambers 60 and 62 in the driven pulley 54. As a result, the movable pulley halves 50b and 54b of the drive pulley 50 and the driven pulley 54 are slid along the axial direction, and the respective widths of the grooves 50c and 54c are continuously changed, whereby the transmission ratio in the CVT 26 is increased. It can be changed steplessly.

  Next, the operation of the pump system 64 at the time of executing half discharge by the pump 68 executed in step S10 will be described. In the switching valve 80, the third oil passage 76 and the fourth oil passage 78 are in communication with each other, and the hydraulic oil P1 and the hydraulic oil P2 are simultaneously flowing through the second oil passage 72 (P1 + P2). .

  First, based on the flowchart of FIG. 5, a control signal is output from the CVT control unit 32 to a control valve (not shown) connected to the pilot port 96 of the switching valve 80, and a pipe is connected to the pilot port 96 based on the control signal. A pilot pressure is urged from the control valve via a path 94.

  Under the action of the pilot pressure supplied from the pilot port 96 to the inside of the switching valve 80, the valve body 90 is displaced in the direction of arrow D against the elastic force of the spring 92. The third oil passage 76 to which the hydraulic oil P2 is supplied from the second discharge port 70b of the pump 68 under the displacement action is connected to and communicates with the second port 88b, and the third port 88c is connected to the fifth oil passage 102. Connected and connected. At this time, the second port 88b connected to the third oil passage 76 and the fourth oil passage 78 are in a non-communication state in which the communication state is blocked.

  Therefore, the hydraulic oil P2 supplied from the third oil path 76 to the second port 88b of the switching valve 80 is led out from the third port 88c to the fifth oil path 102 via the communication path 100, and the fifth It is led out from the oil passage 102 to the first oil passage 66 through the second branch portion 98. The hydraulic oil P <b> 2 is again introduced into the pump 68 through the first oil passage 66.

  That is, the hydraulic oil P2 discharged from the second discharge port 70b of the pump 68 and supplied to the switching valve 80 via the third oil passage 76 communicates with the fourth oil passage 78 inside the switching valve 80. Is cut off, the hydraulic oil P2 does not join the hydraulic oil P1 flowing through the second oil passage 72. Therefore, the hydraulic oil supplied to the first control valve 74 via the second oil passage 72 is only the hydraulic oil P1 discharged from the first discharge port 70a of the pump 68. In other words, the third oil passage 76 and the fourth oil passage 78 are in communication with each other via the switching valve 80, and the hydraulic oil P <b> 2 discharged from the second discharge port 70 b of the pump 68 passes through the switching valve 80. The flow rate of the hydraulic oil supplied to the first control valve 74 is approximately half that of the case where the hydraulic oil is led to the second oil passage 72 (hydraulic oil P1 + P2, flow rate A + B) (hydraulic oil P1, flow rate A ).

  The hydraulic oil P1 is regulated to a predetermined pressure under the action of the pilot pressure supplied to the second and third control valves 82 and 84, respectively, and the drive pulley 50 is passed through the sixth oil passages 106a and 106b. And the hydraulic oil chambers 60 and 62 in the driven pulley 54, respectively. As a result, the movable pulley halves 50b and 54b of the drive pulley 50 and the driven pulley 54 are slid along the axial direction, and the respective widths of the grooves 50c and 54c are continuously changed, whereby the transmission ratio in the CVT 26 is increased. It can be changed steplessly.

  As described above, in this embodiment, the driver shifts to a drive (D range, L range) that is a shift range position when the vehicle moves forward or a reverse (R range) that is a shift range position when the vehicle moves backward. In this state, the engine speed Ne is the idle speed, the vehicle is braked by the driver, and is stopped without the accelerator operation (throttle opening TH is fully closed). When the oil temperature T of the oil is equal to or lower than a predetermined temperature (Tref), various states of the vehicle and the engine 22 are detected by various sensors, and a control signal is sent from the CVT control unit 32 based on the detected results. Is output.

  Then, the switching valve 80 is switched based on the control signal, and the supply amount of hydraulic oil supplied from the pump 68 to the drive pulley 50 and the driven pulley 54 of the CVT 26 is set to the pump 68 when the vehicle is traveling at a low speed. Compared to the amount of hydraulic oil supplied from the engine.

  That is, when the vehicle is stopped and the engine 22 is running at a low speed and in an idling state, the amount of hydraulic oil required in the CVT 26 is small. Therefore, the amount of hydraulic oil supplied from the pump 68 to the CVT 26 Even if it is reduced to approximately half, the capacity of hydraulic oil required for the CVT 26 can be sufficiently satisfied.

  As a result, it is possible to reduce the amount of hydraulic oil supplied from the pump 68 when the vehicle is stopped due to a signal waiting, traffic jam, or the like. For example, even when the frequency of stopping the vehicle increases, The friction loss in the pump 68 is suppressed, and the fuel consumption is reduced accordingly. Therefore, the fuel efficiency can be improved.

  Further, in the case where the supply amount of the hydraulic oil supplied from the pump 68 to the CVT 26 is reduced with the vehicle stopped as described above, for example, the range of the idling engine speed Ne in which the engine speed Ne is set in advance. When the driver is out, the shift change operation is performed by the driver, the brake operation is released, the shift range is other than the forward position (D range, L range) or the reverse position (R range), etc. The state of the vehicle and the engine 22 described above is detected by the sensor, and a control signal based on the detection result is supplied from the CVT control unit 32 to the switching valve 80.

  Then, the flow rate of the hydraulic oil supplied to the drive pulley 50 and the driven pulley 54 via the pump 68 under the switching action of the switching valve 80 increases approximately twice as compared with the state where the vehicle is stopped. Therefore, the amount of hydraulic oil supplied is not insufficient with respect to the volume of hydraulic oil required by the CVT 26, and the required flow rate of hydraulic oil can be suitably supplied to the CVT 26.

  As described above, the switching valve 80 is switched according to the traveling and stopping conditions of the vehicle, and the amount of hydraulic oil supplied to the CVT 26 is changed according to the switching condition, thereby operating in accordance with the situation. The oil supply amount can be reliably and easily supplied, and the friction loss of the pump 68 when the vehicle is stopped can be reduced, so that the fuel efficiency of the vehicle is maintained in a good state.

It is a schematic structure explanatory view of a continuously variable transmission control device according to an embodiment of the present invention. FIG. 2 is an explanatory diagram of a schematic configuration of a pump system in the continuously variable transmission control device of FIG. 1. It is a longitudinal cross-sectional operation | movement explanatory drawing of the switching valve in the pump system of FIG. It is a longitudinal cross-sectional operation | movement explanatory drawing of the switching valve of FIG. It is a flowchart which shows the content which performs the control which switches the discharge amount of a pump among the processing content of a CVT control part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 20 ... Continuously variable transmission control device 22 ... Engine 26 ... CVT 30 ... Main controller 32 ... CVT control part 46 ... Planetary gear type forward / reverse switching mechanism 50 ... Drive pulley 52 ... Metal belt 54 ... Driven pulley 60, 62 ... Hydraulic oil Chamber 64 ... Pump system 65 ... Tank 66 ... First oil passage 68 ... Pump 72 ... Second oil passage 74 ... First control valve 76 ... Third oil passage 78 ... Fourth oil passage 80 ... Switching valve 82 ... Second control Valve 84 ... Third control valve 89 ... First branch 90 ... Valve body 96 ... Pilot port 112 ... Throttle opening sensor 120, 122, 129, 130 ... Speed sensor 124 ... Vehicle speed sensor 132 ... Position switch

Claims (2)

In an oil pump control device for a continuously variable transmission that continuously changes the output shaft and wheel shaft of an engine in a vehicle via hydraulic oil pressure,
The continuously variable transmission oil pump control device includes a variable displacement pump that changes a discharge amount of hydraulic oil supplied to the continuously variable transmission according to an operation state of the vehicle,
When the engine is in an idling state, the amount of hydraulic oil supplied from the variable displacement pump to the continuously variable transmission is hydraulic oil that is discharged when the vehicle is running when the vehicle is stopped. Oil pump control device for continuously variable transmission, characterized in that it is set to be smaller than the discharge amount of the continuously variable transmission. A driving pulley provided on the output shaft side of the engine; a driven pulley provided on the wheel shaft side; and a driving force transmission belt interposed between the driving pulley and the driven pulley. The pulley is displaced by a cylinder mechanism to adjust the groove width of the driving pulley, and the movable pulley in the driven pulley is displaced by a cylinder mechanism to adjust the groove width of the driven pulley, and the engine output in the driving pulley is adjusted. A belt-type continuously variable transmission having a starting mechanism on the shaft side;
In the oil pump control device for continuously variable transmission, the hydraulic oil is supplied to the cylinder mechanism in the drive pulley and the driven pulley, respectively, and the output shaft and the wheel shaft are continuously shifted.
When the engine is in an idling state, the amount of hydraulic oil supplied from the variable displacement pump to the continuously variable transmission is hydraulic oil that is discharged when the vehicle is running when the vehicle is stopped. Oil pump control device for continuously variable transmission, characterized in that it is set to be smaller than the discharge amount of the continuously variable transmission.

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