JP4744498B2 - Control device for continuously variable transmission - Google Patents

Description

  The present invention relates to a control device for a continuously variable transmission, and more specifically to a control device for a braking force by an engine brake during deceleration.

As a conventional technique of a control device for a continuously variable transmission related to a braking force by an engine brake during deceleration, a technique described in Patent Document 1 can be cited. In the technique described in Patent Document 1, when stopping fuel supply to the internal combustion engine is prohibited for catalyst protection, the work of the pump that supplies hydraulic oil to the drive pulley and the driven pulley is increased. Thus, the extra driving force generated by the fuel supply is consumed, and the gear ratio is not changed by supplying to both pulleys.
JP 2004-106782 A

  As described above, in the technique described in Patent Document 1, the increase in driving force due to the prohibition of the stop of fuel supply is offset by increasing the amount of work of the pump. When executed, since the driving force is reduced, the braking force is suddenly increased when the gear ratio is returned to low just before stopping, and it is difficult to obtain the braking force without feeling uncomfortable.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a control device for a continuously variable transmission that eliminates the above-mentioned disadvantages and that can provide a braking force that does not cause a sense of incompatibility when the fuel supply to the internal combustion engine is stopped. .

  In order to achieve the above object, according to a first aspect of the present invention, there is provided a control device for a belt type continuously variable transmission having a drive pulley and a driven pulley for shifting the rotation of an internal combustion engine mounted on a vehicle. A pump driven by an engine to pump hydraulic oil from a reservoir and pump it to an oil passage connected to the oil chambers of the drive pulley and the driven pulley; and the hydraulic oil inserted into the oil passage and supplied to the oil chamber An electromagnetic valve for adjusting the pressure of the vehicle, a fuel supply stop means for stopping fuel supply to the internal combustion engine in a predetermined operating state, a vehicle speed sensor for detecting a vehicle speed indicating the traveling speed of the vehicle, and the fuel supply stopped The pressure of the hydraulic oil supplied to the oil chamber via the electromagnetic valve is increased according to the detected vehicle speed, thereby increasing the work amount of the pump. It was composed as and a engine load increasing means for increasing the load of the internal combustion engine.

  In the continuously variable transmission control device according to claim 2, the engine load increasing means is an operation supplied to the oil chamber in accordance with an input torque of the continuously variable transmission and a margin torque added thereto. The oil pressure is set, and an increase set according to the vehicle speed is added to the margin torque to increase the load on the internal combustion engine.

  In the continuously variable transmission control apparatus according to claim 3, the engine load increasing means is configured to stop the addition of the increase when the vehicle speed rapidly decreases.

  In the control device for continuously variable transmission according to claim 1, a pump that is driven by an internal combustion engine, pumps hydraulic oil from a reservoir, and pumps it to an oil passage connected to an oil chamber of a drive pulley and a driven pulley; An electromagnetic valve that is inserted into the oil passage and adjusts the pressure of the hydraulic oil supplied to the oil chamber, and is supplied to the oil chamber via the electromagnetic valve when the fuel supply to the internal combustion engine is stopped. The hydraulic oil pressure is increased according to the detected vehicle speed, and thus the work load of the pump is increased to increase the load of the internal combustion engine, so the work load of the pump is increased and the load of the internal combustion engine is increased. To increase the braking force of the internal combustion engine, that is, to increase the braking force of the internal combustion engine by first increasing the work amount of the pump, specifically, to reduce the speed ratio of the continuously variable transmission. To go back to low Gradually it becomes possible to increase the braking force by decreasing the load of the pump in accordance with the rapid increase in that the braking force. In this way, by adjusting the braking force when the fuel supply is stopped to the increasing side, it is possible to obtain a braking force with no sense of incongruity.

  In the continuously variable transmission control device according to claim 2, the pressure of the hydraulic oil supplied to the oil chamber is set in accordance with the input torque of the continuously variable transmission and the margin torque added thereto. Since it is configured to increase the load of the internal combustion engine by adding an increase set according to the vehicle speed to the torque, in addition to the above effect, by increasing the margin torque and increasing the work of the pump, There is no change in the gear ratio.

  The control device for the continuously variable transmission according to claim 3 is configured such that the addition of the increase is stopped when the vehicle speed rapidly decreases, so that in addition to the above-described effects, an intended shift can be realized. it can. That is, if the load on the pump is increased during sudden deceleration, the hydraulic oil pressure that returns the gear ratio to low may be insufficient, but during sudden deceleration, the braking force control is stopped to stop the operation required for shifting. The oil pressure can be secured, and the desired gear ratio can be realized.

  The best mode for carrying out a continuously variable transmission control apparatus according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing the overall control device of a continuously variable transmission according to an embodiment of the present invention.

  In FIG. 1, reference numeral 10 indicates an internal combustion engine (hereinafter referred to as “engine”). The engine 10 is mounted on a vehicle (partially indicated by drive wheels W).

  A throttle valve (not shown) arranged in the intake system of the engine 10 is mechanically disconnected from an accelerator pedal (not shown) arranged in the vehicle driver's seat, and is a DBW (actuator) such as an electric motor. Drive By Wire) mechanism 16 is connected and driven.

  The intake air metered by the throttle valve flows through an intake manifold (not shown) and mixes with fuel injected from an injector (fuel injection valve) 20 near the intake port of each cylinder to form an air-fuel mixture, When an intake valve (not shown) is opened, it flows into a combustion chamber (not shown) of the cylinder. In the combustion chamber, the air-fuel mixture is ignited and combusted, and after driving a piston (not shown) to rotate the crankshaft 22, exhaust gas is discharged outside the engine 10.

  The rotation of the crankshaft 22 of the engine 10 is input to the transmission 26 via the torque converter 24. In other words, the crankshaft 22 is connected to the pump / impeller 24a of the torque converter 24, while the turbine runner 24b disposed opposite thereto and receiving fluid (hydraulic oil) is connected to the main shaft (mission input shaft) MS. .

  The transmission 26 includes a continuously variable transmission (hereinafter referred to as “CVT”), and includes a drive pulley 26a disposed on the main shaft MS and a driven pulley 26b disposed on a counter shaft CS parallel to the main shaft MS. And a metal belt 26c hung between them.

  The drive pulley 26a includes a fixed pulley half 26a1 disposed on the main shaft MS and a movable pulley half 26a2 that can move relative to the fixed pulley half 26a1 in the axial direction. The driven pulley 26b includes a fixed pulley half 26b1 fixed to the countershaft CS and a movable pulley half 26b2 that can move relative to the fixed pulley half 26b1 in the axial direction.

  The CVT 26 is connected to the forward / reverse switching device 30. The forward / reverse switching device 30 includes a forward clutch 30a, a reverse brake 30b, and a planetary gear mechanism 30c disposed therebetween.

  In the planetary gear mechanism 30c, the sun gear 30c1 is fixed to the main shaft MS, and the ring gear 30c2 is fixed to the fixed pulley half 26a1 of the drive pulley 26a via the forward clutch 30a.

  A pinion 30c3 is disposed between the sun gear 30c1 and the ring gear 30c2. Pinion 30c3 is coupled to sun gear 30c1 by carrier 30c4. The carrier 30c4 is fixed (locked) when the reverse brake 30b is operated.

  The rotation of the counter shaft CS is transmitted to the secondary shaft SS via the reduction gears 34 and 36, and the rotation of the secondary shaft SS is transmitted to the left and right drive wheels (tires, only shown on the right side) W via the gear 40 and the differential D. It is done. A disc brake 42 is disposed in the vicinity of the drive wheel W.

  Switching between the forward clutch 30a and the reverse brake 30b is performed by the driver operating a shift lever 44 provided at a vehicle driver's seat, for example, having positions P, R, N, D, S, and L. When any position of the shift lever 44 is selected by the driver, the selection operation is transmitted to a manual valve of a hydraulic mechanism (described later) such as the CVT 26.

  For example, when the D, S, and L positions are selected, the spool of the manual valve moves accordingly, and hydraulic oil (hydraulic pressure) is discharged from the piston chamber of the reverse brake 30b, while hydraulic pressure is discharged to the piston chamber of the forward clutch 30a. Is supplied and the forward clutch 30a is engaged (fastened).

  When the forward clutch 30a is engaged, all gears rotate together with the main shaft MS, and the drive pulley 26a is driven in the same direction (forward direction) as the main shaft MS.

  On the other hand, when the R position is selected, hydraulic oil is discharged from the piston chamber of the forward clutch 30a, while hydraulic pressure is supplied to the piston chamber of the reverse brake 30b, and the reverse brake 30b is operated. As a result, the carrier 30c4 is fixed, the ring gear 30c2 is driven in the opposite direction to the sun gear 30c1, and the drive pulley 26a is driven in the opposite direction (reverse direction) to the main shaft MS.

  When the P or N position is selected, the hydraulic oil is discharged from both piston chambers, the forward clutch 30a and the reverse brake 30b are both released, and the power transmission through the forward / reverse switching device 30 is cut off. Power transmission between the engine 10 and the drive pulley 26a of the CVT 26 is interrupted.

  FIG. 2 is a hydraulic circuit diagram schematically showing a hydraulic mechanism such as the CVT 26 described above.

  As shown in the drawing, a hydraulic pump (pump) 46a is provided in the hydraulic mechanism (indicated by reference numeral 46). The hydraulic pump 46a is a gear pump, is driven by the engine 10, pumps up hydraulic oil stored in a reservoir (hydraulic supply source) 46b, and pumps it to a PH control valve (PH REG VLV) 46c.

  On the other hand, the output (PH pressure (line pressure)) of the PH control valve 46c is supplied from the oil passage 46d via the first and second regulator valves (DR REG VLV, DN REG VLV) 46e, 46f. Are connected to the piston chamber (DR) 26a21 of the movable pulley half 26a2 and the piston chamber (DN) 26b21 of the movable pulley half 26b2 of the driven pulley 26b, and on the other hand, the CR valve (CR VLV) via the oil passage 46g. 46h.

  The CR valve 46h reduces the PH pressure to generate a CR pressure (control pressure), and the first, second, and third linear solenoid valves (electromagnetic valves) 46j, 46k, 46l (LS-DR, LS-DN, LS-CPC). The first and second linear solenoid valves 46j and 46k act on the first and second regulator valves 46e and 46f with the output pressure determined according to the excitation of the solenoids, and thus the PH pressure sent from the oil passage 46d. Is supplied to the piston chambers (oil chambers) 26a21 and 26b21 of the movable pulley halves 26a2 and 26b2, and a pulley side pressure is generated accordingly.

  In this way, the hydraulic pump 46a is driven by the engine 10, pumps hydraulic oil from the reservoir 46b, and passes through the PH control valve (PH REG VLV) 46c to the piston chamber (DR) of the movable pulley half 26a2 of the drive pulley 26a of the CVT 26. ) 26a21 and the driven pulley 26b are pressure-fed to an oil passage 46d connected to the piston chamber (DN) 26b21 of the movable pulley half 26b2.

  The first and second linear solenoid valves 46j and 46k are inserted into an oil passage 46i connected to the oil passage 46d via a CR valve 46h, and supplied to the piston chamber (DR) 26a21 and the piston chamber (DN) 26b21. Adjust the hydraulic oil pressure.

  Therefore, in the configuration shown in FIG. 1, the pulley side pressure that moves the movable pulley halves 26a2 and 26b2 in the axial direction is generated, the pulley widths of the drive pulley 26a and the driven pulley 26b change, and the winding radius of the belt 26c changes. Changes. Thus, by adjusting the side pressure of the pulley, the transmission gear ratio for transmitting the output of the engine 10 to the drive wheels W can be changed steplessly.

  Returning to the description of FIG. 2, the output (CR pressure) of the CR valve 46h is also connected to a CR shift valve (CR SFT VLV) 46n, and from there through the above-described manual valve (MAN VLV, indicated by reference numeral 46o). The forward clutch 30a of the forward / reverse switching device 30 is connected to a piston chamber (FWD) 30a1 and a piston chamber (RVS) 30b1 of the reverse brake 30b.

  As described with reference to FIG. 1, the manual valve 46o outputs the output of the CR shift valve 46n according to the position of the shift lever 44 operated (selected) by the driver, and the piston chambers 30a1 of the forward clutch 30a and the reverse brake 30b. Connect to one of 30b1.

  The output of the PH control valve 46c is sent to the TC regulator valve (TC REG VLV) 46q via the oil passage 46p, and the output of the TC regulator valve 46q is LC shifted via the LC control valve (LC CTL VLV) 46r. Connected to valve (LC SFT VLV) 46s. The output of the LC shift valve 46s is connected on the one hand to the piston chamber 24c1 of the lock-up clutch 24c of the torque converter 24, and on the other hand to the backside chamber 24c2.

  The CR shift valve 46n and the LC shift valve 46s are connected to first and second (electromagnetic) on / off solenoids (SOL-A, SOL-B) 46u and 46v, and the oil to the forward clutch 30a is excited or de-energized. The switching of the road and the engagement (on) / release (off) of the lock-up clutch 24c are controlled.

  Regarding the lock-up clutch 24c, the hydraulic oil is supplied to the piston chamber 24c1 via the LC shift valve 46s, while the lock-up clutch 24c is engaged (fastened and turned on) when discharged from the rear chamber 24c2. While being supplied to the chamber 24c2 on the back side, when discharged from the piston chamber 24c1, it is released (not fastened. OFF). The slip amount of the lock-up clutch 24c, that is, the engagement capacity when the lock-up clutch 24c is slipped between engagement and release is determined by the pressure (hydraulic pressure) of the hydraulic oil supplied to the piston chamber 24c1 and the rear chamber 24c2. The

  The third linear solenoid 46l described above is connected to the LC shift valve 46s via the oil passage 46w and the LC control valve 46r, and further connected to the CR shift valve 46n via the oil passage 46x. That is, the engagement capacity (slip amount) of the forward clutch 30a and the lockup clutch 24c is adjusted (controlled) by the excitation / non-excitation of the solenoid of the third linear solenoid valve 46l.

  Returning to the description of FIG. 1, a crank angle sensor 48 is provided at an appropriate position such as near the cam shaft (not shown) of the engine 10 and outputs a signal indicating the engine speed NE for each predetermined crank angle position of the piston. To do. In the intake system, an absolute pressure sensor 50 is provided at an appropriate position downstream of the throttle valve, and outputs a signal proportional to the intake pipe absolute pressure (engine load) PBA.

  The actuator of the DBW mechanism 16 is provided with a throttle opening sensor 52 and outputs a signal proportional to the throttle opening TH through the amount of rotation of the actuator, and an accelerator opening sensor 54 is provided in the vicinity of the accelerator pedal. A signal proportional to the accelerator opening AP corresponding to the accelerator pedal operation amount is output.

  Further, a water temperature sensor 56 is provided in the vicinity of a cooling water passage (not shown) of the engine 10 to generate an output corresponding to the engine cooling water temperature TW, in other words, the temperature of the engine 10, and the intake air temperature in the intake system. A sensor 58 is provided and generates an output corresponding to the intake air temperature (outside air temperature) taken into the engine 10.

  The output of the crank angle sensor 48 and the like described above is sent to the engine controller 60. The engine controller 60 includes a microcomputer, determines the target throttle opening based on the sensor outputs, controls the operation of the DBW mechanism 16, and determines the fuel injection amount to drive the injector 20.

  The main shaft MS is provided with an NT sensor (rotational speed sensor) 62, which determines the rotational speed of the turbine runner 24b, specifically the rotational speed of the main shaft MS, more specifically the input shaft rotational speed of the forward clutch 30a. The pulse signal shown is output.

  An NDR sensor 64 is provided at an appropriate position in the vicinity of the drive pulley 26a of the CVT 26, and outputs a pulse signal corresponding to the rotational speed of the drive pulley 26a, in other words, the output shaft rotational speed of the forward clutch 30a. An NDN sensor (rotational speed sensor) 66 is provided at an appropriate position near the pulley 26b, and outputs a pulse signal indicating the rotational speed of the driven pulley 26b.

  A VEL sensor (rotational speed sensor) 70 is provided in the vicinity of the gear 36 of the secondary shaft SS, and outputs a pulse signal indicating the output shaft of the CVT 26 or the vehicle speed VEL through the rotational speed of the gear 36. A shift lever position sensor 72 is provided in the vicinity of the shift lever 44 described above, and outputs a POS signal corresponding to a position such as R, N, or D selected by the driver.

  The output of the NT sensor 62 and the like described above is sent to the shift controller 74 including the outputs of other sensors (not shown). The shift controller 74 also includes a microcomputer and is configured to be able to communicate with the engine controller 60.

  Based on these detected values, the shift controller 74 selects one of the first and second on / off solenoids 46u and 46v of the hydraulic mechanism 46 and the first, second and third linear solenoid valves 46j, 46k and 46l. These electromagnetic solenoids are energized / de-energized to control the engagement (engaged, on) / release (non-engaged, off) of the lockup clutch 24c of the forward / reverse switching device 30, the CVT 26, and the torque converter 24.

  Furthermore, the shift controller 74 also controls the braking force by the engine brake during deceleration.

  FIG. 3 is a flowchart showing the operation of the shift controller 74. The illustrated program is executed by the shift controller 74 at a predetermined time, for example, every 10 msec during in-gear.

  In the following description, in step S10, AP OFF is determined, that is, whether the accelerator pedal is not operated by the driver, in other words, whether the throttle opening is fully closed is determined from the output of the accelerator opening sensor 56, and is affirmed. If so, the process proceeds to S12, in which it is determined whether the vehicle 14 is slowly decelerating (whether the vehicle speed is not rapidly decreasing). This is determined by calculating the first-order difference value of the vehicle speed VEL detected by the VEL sensor 70.

  The shift controller 74 accesses the engine controller 60 and inputs the output of a sensor sent to the engine controller 60 such as the accelerator opening sensor 56.

  When the result in S12 is affirmative, the program proceeds to S14, in which it is determined whether the fuel supply to the engine 10 is stopped during F / C, that is, in a predetermined operating state.

  When the result in S14 is affirmative, the program proceeds to S16, in which it is determined whether or not the deviation between the detected engine speed NE and the F / C return engine speed NFCT is large. That is, if the work amount of the hydraulic pump 46a is increased in the state of returning from the F / C, the fuel consumption is also deteriorated. Therefore, the deviation between the detected engine speed NE and the F / C return engine speed NFCT is appropriately set. By comparing with a threshold value to be determined, it is determined whether or not it is immediately before returning from F / C.

  When the result in S16 is affirmative and it is determined that it is not immediately before returning from the F / C, the process proceeds to S18 and the deceleration margin torque is set.

  To explain this, although not shown in detail, in another routine (not shown), the drive pulley 26a and the driven pulley 26b are based on the input torque obtained from the engine speed NE and the engine load (for example, the intake pipe absolute pressure PBA). The basic value of the hydraulic pressure supplied to each is calculated.

  As the basic value of the hydraulic pressure supplied to the drive pulley 26a and the driven pulley 26b, an added value of the hydraulic pressure is calculated according to the gear ratio (RATIO), and a surplus torque is added. The margin torque is a torque added as a margin for reliably preventing the belt 26c from slipping.

  In S18, an increase to be added to the margin torque is set according to the detected vehicle speed VEL, that is, so as to increase as the vehicle speed VEL increases. Since the increment is equally applied to the drive pulley 26a and the driven pulley 26b, the gear ratio does not change.

  In another routine (not shown), the pressure of hydraulic oil to be supplied to the drive pulley 26a and the driven pulley 26b, that is, the hydraulic pressure is calculated according to the sum of the basic value, the added value corresponding to the gear ratio, and the surplus torque. Then, the hydraulic pump 46a is driven so as to achieve the hydraulic pressure, and energization of the first and second linear solenoid valves 46j and 46k is controlled.

  Accordingly, when the process of S18 is performed, the pressure of the hydraulic oil to be supplied to the drive pulley 26a and the driven pulley 26b increases by an increase to be added to the surplus torque. As a result, the work (driving amount) of the hydraulic pump 46a is increased by that amount. ) Is increased, and the load on the engine 10 that drives the hydraulic pump 46a increases. As a result, the braking force by the engine 10 can be increased, and the braking force by the engine brake can be obtained without a sense of incongruity.

  In other words, since the work amount of the hydraulic pump 46a is first increased, the load of the hydraulic pump 46a is reduced in response to a sudden increase in braking force due to the subsequent change in the gear ratio of the CVT 26. The power can be gradually increased. Therefore, even when the braking force is generated by the F / C, a braking force without a sense of incongruity can be obtained.

  On the other hand, if the result in S10 to S16 is negative, for example, if it is determined in S12 that the vehicle 14 is not slowly decelerating, that is, if the vehicle speed is suddenly reduced, the process proceeds to S20, and the normal margin torque is set. That is, only the original margin torque is set, and the increment to be added to the margin torque is set to zero. Therefore, the work (driving amount) of the hydraulic pump 46a is not increased by the increased amount, and the load on the engine 10 is not increased.

  If it is determined in S12 that the vehicle speed is suddenly reduced, the process proceeds to S20. If the load of the hydraulic pump 46a is increased when the vehicle speed VEL is suddenly reduced, the hydraulic pressure for returning the gear ratio to low is insufficient. In addition, by stopping the control of the braking force during sudden deceleration, it is possible to secure the pressure of the hydraulic oil necessary for gear shifting and to realize the desired gear ratio.

  Moreover, although the case where the load of the engine 10 is increased in S18 has been described, the DBW mechanism 16 is driven as necessary to open the throttle opening so that the necessary braking force by the engine brake can be obtained more comfortably. You may drive to the side. As a result, the pumping loss is reduced, and the load on the engine 10 is reduced. As a result, the braking force by the engine brake is reduced. Therefore, a braking force with a more uncomfortable feeling can be obtained by appropriately combining an increase and a decrease in the load of the engine 10.

  As described above, in this embodiment, the belt-type CVT (continuously variable transmission) 26 having the drive pulley 26a and the driven pulley 26b for shifting the rotation of the engine (internal combustion engine) 10 mounted on the vehicle 14 is used. In a control device (shift controller 74), an oil passage 46d is driven by the engine 10 and pumps hydraulic oil from a reservoir 46b and is connected to piston chambers (oil chambers) 26a21 and 26b21 of the drive pulley 26a and the driven pulley 26b. First and second linear solenoid valves (adjusted by a hydraulic pump (pump) 46a for pressure feeding) and an oil passage 46i connected to the oil passage 46d for adjusting the pressure of hydraulic oil supplied to the oil chamber ( Electromagnetic valves) 46j, 46k, and fuel supply for stopping fuel supply to the engine 10 in a predetermined operating state. Stop means (S10 to S16), a VEL sensor (vehicle speed sensor) 70 for detecting a vehicle speed VEL indicating the traveling speed of the vehicle 14, and when the fuel supply is stopped (F / C), the electromagnetic valve An engine load increasing means for increasing the pressure of the hydraulic oil supplied to the oil chamber according to the detected vehicle speed VEL, thereby increasing the amount of work of the hydraulic pump 46a and increasing the load of the engine 10. S18), the engine brake is increased by increasing the load of the engine 10 by increasing the work amount of the hydraulic pump 46a, that is, the work amount of the hydraulic pump 46a is first increased. After the brake is increased, the hydraulic pump 46 is decreased in response to a sudden increase in braking force caused by the gear ratio of the CVT 26 returning to low. Gradually it becomes possible to increase the braking force by decreasing the load. In this way, by adjusting the braking force when the fuel supply is stopped to the increasing side, it is possible to obtain a braking force with no sense of incongruity.

  The engine load increasing means sets the pressure of the hydraulic oil supplied to the oil chamber according to the input torque of the CVT and a margin torque added thereto, and the margin torque according to the vehicle speed VEL. Since the load of the internal combustion engine is increased by adding the set increase (S18), the margin ratio is increased to increase the work of the hydraulic pump 46a, thereby causing a change in the gear ratio. There is nothing.

  Further, since the engine load increasing means is configured to stop the addition of the increase when the vehicle speed VEL decreases rapidly, in addition to the effects described above, an expected shift can be realized.

  In the above description, the belt-type CVT 26 is disclosed as a continuously variable transmission. However, the present invention is not limited to this, and the present invention is also applicable to other continuously variable transmissions.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an overall control device for a continuously variable transmission according to an embodiment of the present invention. FIG. 2 is a hydraulic circuit diagram showing a hydraulic mechanism of a continuously variable transmission and a torque converter shown in FIG. 1. It is a flowchart which shows operation | movement of the apparatus shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Internal combustion engine (engine), 14 Vehicle, 16 DBW mechanism, 24 Torque converter, 26 Continuously variable transmission (CVT), 30 Forward / reverse switching device, 30a Forward clutch (clutch), 46 Hydraulic mechanism, 46a Pump (hydraulic pump) 46j, 46k Solenoid valves (first and second linear solenoid valves), 46s switching valve (LC shift valve), 48 crank angle sensor, 50 absolute pressure sensor, 54 accelerator opening sensor, 60 engine controller, 70 VEL sensor, 74 Shift controller

Claims (3)

In a control device for a belt-type continuously variable transmission having a drive pulley and a driven pulley for shifting the rotation of an internal combustion engine mounted on a vehicle,
a. A pump that is driven by the internal combustion engine, pumps hydraulic oil from a reservoir, and pumps it to an oil passage connected to an oil chamber of the drive pulley and the driven pulley;
b. An electromagnetic valve that is inserted into the oil passage and adjusts the pressure of hydraulic oil supplied to the oil chamber;
c. Fuel supply stopping means for stopping fuel supply to the internal combustion engine in a predetermined operating state;
d. A vehicle speed sensor for detecting a vehicle speed indicating the traveling speed of the vehicle;
e. When the fuel supply is stopped, the pressure of the hydraulic oil supplied to the oil chamber via the electromagnetic valve is increased according to the detected vehicle speed, thereby increasing the work amount of the pump and the internal combustion engine. Engine load increasing means for increasing engine load;
A control device for a continuously variable transmission.   The engine load increasing means sets the pressure of hydraulic oil supplied to the oil chamber according to the input torque of the continuously variable transmission and the margin torque added thereto, and the margin torque according to the vehicle speed. 2. The continuously variable transmission control device according to claim 1, wherein a load of the internal combustion engine is increased by adding a set increase.   3. The continuously variable transmission control device according to claim 1, wherein the engine load increasing unit stops adding the increased amount when the vehicle speed rapidly decreases.

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