JP2009293712A - Oil pump drive unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil pump drive unit capable of discharging working oil by suitably driving an oil pump even when the working oil has high viscosity. <P>SOLUTION: The oil pump drive unit includes an engine 5 being a driving source of the oil pump 12, a high-rotation drive passage 21 capable of transmitting the rotation of the engine 5 into the oil pump 12, a low-rotation drive passage 20 capable of transmitting the rotation of the engine 5 into oil pump 12, a passage switching mechanism 25 capable of switching the passage between the high-rotation drive passage 21 and the low-rotation drive passage 20, an oil temperature sensor 27 capable of detecting the temperature of the working oil, and an oil temperature switching control part 105 for controlling the switching of the passage switching mechanism 25 based on the detected temperature of the working oil. The oil temperature switch control part 105 performs switching to the low-rotation drive passage 20 when the detected temperature of the working oil is lower than a set temperature. When the detected temperature of the working oil is not less than the set temperature, the oil temperature switching control part 105 performs switching to the high-rotation drive passage 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an oil pump drive device that operates an oil pump capable of discharging hydraulic oil using an engine as a drive source.

  The oil pump supplies hydraulic oil to, for example, a toroidal continuously variable transmission. In the toroidal-type continuously variable transmission, a power roller whose outer peripheral surface is a curved surface corresponding to the toroidal surface is disposed between an input disk and an output disk having a toroidal surface. The toroidal continuously variable transmission sandwiches the power roller by the hydraulic oil pressure, and transmits the torque using the shear force of the hydraulic oil film formed between the input disk, output disk and power roller. is doing. At this time, the power roller is rotatably supported by the trunnion, and the trunnion is swung in the direction along the swing shaft by the hydraulic pressure of the hydraulic oil.

  Accordingly, the power roller supported by the trunnion moves together with the trunnion from the neutral position with respect to the input disk and the output disk to the speed change position, so that a tangential force acts between the power roller and the disk and a side slip occurs. As a result, the power roller swings, that is, tilts with respect to the input disk and the output disk about the swing axis, and as a result, the speed ratio, which is the rotation speed ratio between the input disk and the output disk, is changed. The

  Here, the oil pump is normally driven by an engine, and hydraulic oil is driven by the engine to supply hydraulic oil to the toroidal continuously variable transmission. At this time, the hydraulic oil used in the toroidal type continuously variable transmission has a high viscosity at low temperatures and is difficult to flow. For this reason, when the engine is started and the oil pump is driven at a low temperature, the hydraulic oil hardly flows, so that the pump driving torque for driving the oil pump becomes excessive.

  For this reason, as a conventional oil pump drive device, an oil pump control device configured to replace the oil in the oil pump with air when the engine is started is known (for example, see Patent Document 1).

JP-A-1-135948

  However, in the conventional oil pump control device, since the air is pumped instead of the oil when the engine is started, the oil does not easily flow. If the oil does not flow, the oil does not circulate through the hydraulic system, so that it is difficult to promote the temperature rise of the oil due to the circulation. As a result, the oil temperature is unlikely to rise, so the viscosity of the oil cannot be lowered, and it takes a considerable time to raise the temperature of the oil that can be pumped by the oil pump. Further, if the transmission is operated in a state where the air is replaced, there is a risk that a load is applied to the transmission because the transmission operates in a state where no lubricating oil is supplied.

  Therefore, an object of the present invention is to provide an oil pump drive device that can suitably drive an oil pump and discharge the hydraulic oil even when the viscosity of the hydraulic oil is high.

  The oil pump drive device of the present invention transmits an engine serving as a drive source of an oil pump capable of discharging hydraulic oil, a high rotation drive path capable of transmitting engine rotation to the oil pump, and engine rotation transmitted to the oil pump. In addition, a low-rotation drive path configured to have a larger reduction ratio than a high-rotation drive path, and path switching that can selectively switch between a high-rotation drive path and a low-rotation drive path Means, hydraulic oil viscosity detecting means capable of detecting the viscosity of the hydraulic oil, and switching control means for switching and controlling the path switching means based on the detected viscosity of the hydraulic oil, the switching control means being detected If the viscosity of the hydraulic oil is equal to or higher than a predetermined viscosity, the operation is switched to the low rotation drive path. On the other hand, if the detected viscosity of the hydraulic oil is less than the predetermined viscosity, the operation oil is switched to the high rotation drive path.

  In this case, the predetermined viscosity may be a threshold value for determining whether or not the oil pump can be operated based on the engine output torque transmitted through the high rotation drive path. ,preferable.

  In these cases, it is preferable that the switching control means performs path switching by the path switching means before the engine is started.

  In these cases, the hydraulic oil viscosity detection means has an oil temperature detection means capable of detecting the temperature of the hydraulic oil, and the switching control means switches and controls the path switching means based on the detected temperature of the hydraulic oil. The oil temperature switching control means has an oil temperature switching control means, and when the detected temperature of the operating oil is lower than a preset temperature, the oil temperature switching control means switches to the low rotation driving path while detecting the detected operating oil. When the temperature is higher than the set temperature, it is preferable to switch to the high rotation drive path.

  In this case, the set temperature is preferably a threshold value for determining whether the viscosity of the hydraulic oil is equal to or higher than the predetermined viscosity or lower than the predetermined viscosity.

  In these cases, it is preferable that the switching control means further includes an engine start switching control means for switching to the high rotation drive path after the engine is started.

  Further, in these cases, the engine speed detecting means for detecting the engine speed is further provided, and the switching control means has a speed switching control means for switching the path switching means based on the detected engine speed. When the detected engine speed is equal to or higher than a preset rotational speed, the rotational speed switching control means switches to the low-rotation driving path while the detected engine rotational speed is set to the set rotational speed. If it is less, it is preferable to switch to the high rotation drive path.

  In this case, it is preferable that the set rotational speed is a threshold value for determining whether or not the required discharge amount required for the oil pump can be discharged.

  In these cases, it is preferable that the rotation speed switching control means performs path switching by the path switching means after the engine is started.

  In these cases, the path switching means is a first switch that can be switched between a power transmission state that connects the high rotation drive path and the oil pump and a power non-transmission state that disconnects the high rotation drive path and the oil pump. And a second switching means switchable between a power transmission state connecting the low rotation driving path and the oil pump and a power non-transmission state cutting the low rotation driving path and the oil pump. It is preferable.

  In this case, it is preferable that the first switching means is an electromagnetic clutch.

  In these cases, it is preferable that the second switching means is a one-way clutch.

  In these cases, it is preferable that the high-rotation drive path, the low-rotation drive path, and the path switching unit are configured by a planetary gear mechanism.

  An oil pump drive device according to the present invention includes a low rotation drive path capable of transmitting engine output to an oil pump according to the viscosity of hydraulic oil, a high rotation drive path capable of transmitting engine output to an oil pump, The route can be selectively switched between. For this reason, the oil pump drive device can drive the oil pump via the low rotation drive path if the viscosity of the hydraulic oil is equal to or higher than a predetermined viscosity (high viscosity). Accordingly, the engine output torque is amplified through the low rotation drive path, and the oil pump can be driven by the amplified engine output torque. As described above, even if the viscosity of the hydraulic oil is high, there is an effect that the hydraulic pump can be suitably driven to supply the hydraulic oil.

  Hereinafter, an oil pump driving device according to the present invention will be described with reference to the accompanying drawings. Note that the present invention is not limited to the embodiments. In addition, constituent elements in the following embodiments include those that can be easily replaced by those skilled in the art or those that are substantially the same.

  Here, FIG. 1 is a schematic configuration diagram of a drive system of a vehicle equipped with the oil pump driving device according to the first embodiment, and FIG. 2 is a schematic configuration diagram of the oil pump driving device according to the first embodiment. FIG. 3 is a flowchart relating to a series of controls of the oil pump drive device.

  First, a vehicle 1 equipped with an oil pump drive device 13 will be described with reference to FIG. The vehicle 1 includes an engine 5 serving as a drive source, a torque converter 6 coupled to the engine 5, a forward / reverse switching mechanism 7 coupled to the torque converter 6, and a toroidal stepless coupled to the forward / reverse switching mechanism 7. A transmission 8 is provided. A reduction gear 9 is connected to the toroidal continuously variable transmission 8, a differential gear 10 is connected to the reduction gear 9, and a drive wheel 11 is connected to the differential gear 10. Further, the vehicle 1 is provided with a hydraulic system (not shown) that supplies hydraulic oil to each component such as the engine 5, the torque converter 6, the forward / reverse switching mechanism 7, the toroidal continuously variable transmission 8, and the like. The system has an oil pump 12 that serves as a supply source of hydraulic oil. At this time, the oil pump 12 is driven by the driving force transmitted from the oil pump driving device 13 mounted on the vehicle 1 (details will be described later). And the vehicle 1 is provided with ECU100 (refer FIG. 2) which controls these collectively.

  For example, a gasoline engine or a diesel engine is used as the engine 5, and the piston reciprocates in the central axis direction of the cylinder formed in a cylindrical shape, and the crankshaft 15 converts the reciprocating motion of the piston into a rotational motion. Outputs driving force. In addition, not only said structure but electric motors, such as a motor, may be used, and an engine and an electric motor may be used together.

  Although described in detail later, the torque converter 6 is a type of fluid clutch, and transmits the driving force output from the engine 5 to the forward / reverse switching mechanism 7 via hydraulic oil.

  The forward / reverse switching mechanism 7 switches the rotation direction of the rotation from the torque converter 6 and transmits the rotation to the toroidal continuously variable transmission 8.

  The toroidal continuously variable transmission 8 changes the rotational speed of the driving force input from the forward / reverse switching mechanism 7 to a desired rotational speed according to the driving state of the vehicle 1 and outputs it. In the first embodiment, in view of the peculiarity that the hydraulic oil used for the toroidal-type continuously variable transmission 8 has a higher viscosity at low temperatures than the hydraulic oil used for other transmissions. A description will be given by applying the continuously variable transmission 8. However, the present invention is not limited to the toroidal-type continuously variable transmission 8, but may be applied to a transmission such as a belt-type continuously variable transmission or a multi-stage transmission.

  The reduction gear 9 reduces the rotational speed of the driving force input from the toroidal-type continuously variable transmission 8 and transmits the driving force to the differential device 10. The differential device 10 is generated when the vehicle 1 turns. The difference in speed between the center side of the turn, that is, the inner driving wheel 11 and the outer driving wheel 11 is absorbed.

  Therefore, when the engine 5 is driven in the vehicle 1, the driving force output from the engine 5 is transmitted to the torque converter 6 via the crankshaft 15. The driving force output from the torque converter 6 is transmitted to the forward / reverse switching mechanism 7 and is changed to a desired rotational direction by the forward / backward switching mechanism 7. The driving force in the desired rotational direction is input to the toroidal continuously variable transmission 8, and the rotational speed of the input driving force is changed according to a predetermined speed ratio of the toroidal continuously variable transmission 8. The The driving force whose rotational speed has been changed by the toroidal continuously variable transmission 8 is input to the speed reducer 9, and the input driving force is decelerated by the speed reducer 9 and then output to the differential device 10. . Then, the differential device 10 transmits the input driving force to the driving wheels 11, so that the driving wheels 11 rotate, and thereby the vehicle 1 travels.

  Next, the oil pump drive device 13 will be described with reference to FIG. The oil pump drive device 13 includes the engine 5 as a drive source of the oil pump 12. The oil pump drive device 13 includes a low rotation drive path 20 capable of transmitting the output of the engine 5 to the oil pump 12, a high rotation drive path 21 capable of transmitting the output of the engine 5 to the oil pump 12, and a low rotation drive. A path switching mechanism 25 (path switching means) capable of selectively switching the path between the path 20 and the high rotation drive path 21 is provided. The path switching mechanism 25 is controlled to be switched by the ECU 100.

  The engine 5 outputs driving force from the crankshaft 15 as described above. The crankshaft 15 of the engine 5 is provided with an electromagnetic clutch 45 of a path switching mechanism 25 described later, and an output gear 35 is provided on the electromagnetic clutch 45 on the torque converter 6 side. An oil temperature sensor 27 (oil temperature detecting means) for detecting the oil temperature of the hydraulic oil (lubricating oil) supplied from the oil pump 12 is provided inside the engine 5. A crank angle sensor 28 is provided around the shaft 15. The oil temperature sensor 27 and the crank angle sensor 28 are connected to the ECU 100, and the ECU 100 performs switching control of the path switching mechanism 25 based on the detection result by the oil temperature sensor 27, or the detection result by the crank angle sensor 28. Based on this, switching control of the path switching mechanism 25 is performed.

  The oil pump 12 has an input shaft 40, and driving force is transmitted to the input shaft 40. An input gear 43 is disposed on the input shaft 40, and a one-way clutch 46 of the path switching mechanism 25 described later is disposed on the oil pump 12 side of the input gear 43. When power is transmitted to the input shaft 40, the oil pump 12 is driven by the rotation of the input shaft 40, and the driven oil pump 12 supplies hydraulic oil into the hydraulic system.

  The path switching mechanism 25 includes an electromagnetic clutch 45 (first switching means) interposed between the crankshaft 15 of the engine 5 and the high rotation drive path 21, the input shaft 40 of the oil pump 12, and the low rotation drive path 20. And a one-way clutch 46 (second switching means) interposed therebetween.

  The electromagnetic clutch 45 is a known one and connects and disconnects the crankshaft 15 of the engine 5 and the high rotation drive path 21. Further, the electromagnetic clutch 45 is connected to the ECU 100, and the switching operation by the ECU 100 causes the electromagnetic clutch 45 to perform a coupling operation or a coupling releasing operation.

  The one-way clutch 46 is a known one and connects and disconnects the input shaft 40 of the oil pump 12 and the low-rotation drive path 20. In other words, the one-way clutch 46 rotates the input shaft 40 by the driving force transmitted from the low rotation driving path 20, and idles with respect to the input shaft 40 that rotates by the driving force transmitted from the high rotation driving path 21.

  The low rotation drive path 20 is connected to an output gear 35 provided on the crankshaft 15 of the engine 5 on the upstream side and connected to a one-way clutch 46 provided on the input shaft 40 of the oil pump 12 on the downstream side. The low-rotation drive path 20 is configured to increase the reduction ratio, and amplifies the output torque output from the engine 5. Accordingly, by transmitting the output of the engine 5 to the oil pump 12 via the low rotation drive path 20, the oil pump 12 can be operated even if the viscosity of the hydraulic oil is high. That is, the low rotation drive path 20 amplifies the output torque of the engine 5 so that the oil pump 12 can be driven even when the hydraulic oil has a high viscosity. The low-rotation drive path 20 may transmit the output of the engine 5 to the one-way clutch 46 via the output gear 35, and may be configured by a plurality of reduction gear trains, for example.

  The high rotation drive path 21 has an upstream side connected to an electromagnetic clutch 45 provided on the crankshaft 15 of the engine 5, and a downstream side connected to an input gear 43 provided on the input shaft 40 of the oil pump 12. Further, the high rotation drive path 21 is configured so that the reduction ratio is smaller than that of the low rotation drive path 20. That is, the high rotation drive path 21 converts the rotation speed output from the engine 5 so as to be higher than the low rotation drive path 20. Thus, the oil pump 12 can be operated at a high speed by transmitting the output of the engine 5 to the oil pump 12 via the high-rotation drive path 21, so that the amount of hydraulic oil discharged from the oil pump 12 can be reduced. Can be increased. In other words, the high rotation drive path 21 increases the discharge amount of the hydraulic oil discharged from the oil pump 12. The high rotation drive path 21 only needs to transmit the output of the engine 5 to the input gear 43 via the electromagnetic clutch 45. Like the low rotation drive path 20, the high rotation drive path 21 is configured by a plurality of reduction gear trains, for example. Also good.

  Therefore, when the electromagnetic clutch 45 of the path switching mechanism 25 is in the disengaged state (power non-transmission state), part of the driving force output from the engine 5 is the output gear 35, the low-rotation driving path 20, and the one-way clutch. It is input to the input shaft 40 of the oil pump 12 through 46. And the oil pump 12 act | operates because the input shaft 40 rotates. As a result, the oil pump drive device 13 can increase the output torque of the engine 5 through the low-rotation drive path 20, so that the oil pump 12 is operated when the hydraulic oil has a high viscosity. Can do.

  On the other hand, when the electromagnetic clutch 45 of the path switching mechanism 25 is in the connected state (power transmission state), a part of the driving force output from the engine 5 passes through the electromagnetic clutch 45, the high rotation driving path 21 and the input gear 43. Through the input shaft 40 of the oil pump 12. And the oil pump 12 act | operates because the input shaft 40 rotates. At this time, the input shaft 40 of the oil pump 12 that rotates via the input gear 43 idles in the one-way clutch 46, so that no power is transmitted to the low-rotation drive path 20. Thereby, the oil pump drive device 13 can increase the discharge amount of the hydraulic oil discharged from the oil pump 12 as compared with the case of driving through the low rotation drive path 20.

  The ECU 100 includes an oil temperature switching control unit 105 (oil temperature switching control unit) that performs switching control of the path switching mechanism 25 based on the detection result of the oil temperature sensor 27, and an engine start switching that switches to the high-rotation driving path 21 after the engine is started. A control unit 107 (engine start switching control unit) and a rotation number switching control unit 106 (rotation number switching control unit) that performs switching control of the path switching mechanism 25 based on the detection result of the crank angle sensor 28 are provided. .

  When the temperature of the hydraulic oil detected by the oil temperature sensor 27 is lower than the preset temperature, the oil temperature switching control unit 105 releases the connection of the electromagnetic clutch 45 and switches to the low rotation driving path 20. On the other hand, when the temperature of the hydraulic oil detected by the oil temperature sensor 27 is equal to or higher than the set temperature, the oil temperature switching control unit 105 connects the electromagnetic clutch 45 and switches to the high rotation drive path 21. At this time, the set temperature is a threshold value for determining whether or not the viscosity of the hydraulic oil is equal to or higher than a predetermined viscosity. That is, since the viscosity of the hydraulic oil depends on the temperature of the hydraulic oil, the viscosity of the hydraulic oil is high when the temperature of the hydraulic oil is low, and the viscosity of the hydraulic oil is low when the temperature of the hydraulic oil is high. Therefore, the oil temperature sensor 27 functions as hydraulic oil viscosity detection means for determining whether or not the viscosity of the hydraulic oil is equal to or higher than a predetermined viscosity. At this time, the predetermined viscosity (set temperature) is set to the highest viscosity among the viscosities that can drive the oil pump 12 by the output torque of the engine 5 output via the high rotation drive path 21. Is set. That is, the oil pump drive device 13 cannot operate the oil pump 12 through the high rotation drive path 21 if the viscosity (temperature) of the hydraulic oil is equal to or higher than a predetermined viscosity (less than the set temperature). The oil pump 12 is operated via the drive path 20.

  The engine start switching control unit 107 releases the connection of the electromagnetic clutch 45 before starting the engine to form the low rotation drive path 20, and connects the electromagnetic clutch 45 after the engine starts to connect the electromagnetic clutch 45 to the high rotation drive path 21. It has been switched to. Thereby, the engine start switching control unit 107 can make the high-rotation drive path 21 after the engine 5 is started appropriately.

  The rotation speed switching control unit 106 switches to the low rotation driving path 20 when the engine rotation speed calculated based on the detection result of the crank angle sensor 28 is equal to or higher than a preset rotation speed. On the other hand, the rotation speed switching control unit 106 switches to the high rotation drive path 21 when the engine rotation speed calculated based on the detection result of the crank angle sensor 28 is less than the set rotation speed. At this time, the set rotational speed is a threshold value for determining whether or not the required discharge amount of hydraulic oil required for the oil pump 12 can be discharged. For this reason, the set rotational speed is a rotational speed in the vicinity of the engine rotational speed necessary for discharging the required discharge amount. That is, if the engine speed detected by the crank angle sensor 28 is equal to or higher than the set speed, the rotation speed switching control unit 106 determines that the oil pump 12 is discharging hydraulic oil that exceeds the required discharge amount. In this case, the rotation speed switching control unit 106 switches to the low rotation driving path 20 on the assumption that the supply of hydraulic oil is excessive. On the other hand, if the engine rotational speed detected by the crank angle sensor 28 is less than the set rotational speed, the rotational speed switching control unit 106 determines that the oil pump 12 is discharging hydraulic oil that is less than the required discharge amount. In this case, the rotation speed switching control unit 106 switches to the high rotation drive path 21 because the supply of hydraulic oil is insufficient.

  Next, a series of controls of the oil pump drive device 13 according to the present embodiment will be described with reference to FIG. First, when the vehicle 1 is turned on (S1), the oil temperature switching control unit 105 of the ECU 100 detects by the oil temperature sensor 27 in order to determine whether the viscosity of the hydraulic oil is high or low. It is determined whether or not the temperature of the applied hydraulic oil is equal to or higher than a set temperature (S2). When the hydraulic oil is lower than the set temperature, that is, when the hydraulic oil has a high viscosity, the pump driving torque for driving the oil pump 12 becomes excessive, and the engine 5 may not be started properly. There is. For this reason, the oil temperature switching control part 105 cancels | releases the connection by the electromagnetic clutch 45, and switches to the low rotation drive path | route 20 (S3). On the other hand, when the hydraulic oil is higher than the set temperature, that is, when the hydraulic oil has a low viscosity, the pump drive torque for driving the oil pump 12 does not become excessive, and the engine 5 is preferably started. Meanwhile, the oil pump 12 can be driven. Therefore, the oil temperature switching control unit 105 connects the electromagnetic clutch 45 and switches to the high rotation driving path 21 (S4).

  Subsequently, the ECU 100 starts the engine 5 while switching to the low rotation driving path 20 (S5). Then, when the engine start switching control unit 107 of the ECU 100 detects that the engine 5 has been rotated by the crank angle sensor 28, the engine start switching control unit 107 switches from the low rotation drive path 20 to the high rotation drive path 21 (S6), and then proceeds to S8. To do. Thereby, after the engine 5 is suitably started, the oil pump 12 can be driven via the high rotation drive path 21. On the other hand, when the ECU 100 starts the engine 5 while switching to the high rotation drive path 21 (S7), the ECU 100 proceeds to S8 in this state.

  Subsequently, the engine speed control unit 106 of the ECU 100 detects the engine speed detected by the crank angle sensor 28 in order to determine whether or not hydraulic oil exceeding the required discharge amount required for the oil pump 12 is discharged. Is greater than or equal to the set rotational speed (S8). When the engine speed is equal to or higher than the set speed, the rotational speed switching control unit 106 determines that the discharge amount from the oil pump 12 is equal to or higher than the required discharge amount, and releases the connection of the electromagnetic clutch 45 to reduce the low rotation drive path. 20 (S9). Thereby, since the oil pump 12 can be driven at low rotation, the oil pump drive device 13 can reduce the discharge amount of the oil pump 12. On the other hand, when the engine rotational speed is less than the set rotational speed, the rotational speed switching control unit 106 determines that the discharge amount from the oil pump 12 is less than the required discharge amount, and connects the electromagnetic clutch 45 to the high rotation drive path. Switch to 21 (S10). Thereby, since the oil pump 12 can be driven at a high rotation, the oil pump drive device 13 can increase the discharge amount of the oil pump 12. Then, after performing the switching control in S9 or S10, the ECU 100 returns to S8 and repeatedly executes a series of switching control between S8 and S10 during operation of the engine 5.

  In the first embodiment, the route switching by the rotation speed switching control unit 106 is performed after the engine is started, but the route switching by the oil temperature switching control unit 105 may be performed after the engine is started.

  According to the above configuration, the oil pump drive device 13 can selectively switch the low rotation drive path 20 or the high rotation drive path 21 based on the temperature of the hydraulic oil. Thereby, the oil pump drive device 13 can transmit the output of the engine 5 to the oil pump 12 via the low rotation drive path 20 when the hydraulic oil has a high viscosity. The output torque of the engine 5 can be increased through the low rotation drive path 20, and the oil pump 12 can be driven by the increased output torque. For this reason, when the hydraulic oil has a high viscosity, the oil pump drive device 13 can reduce the pump drive torque applied to the engine 5, so that the engine 5 is preferably started when the engine 5 is started. Can do. Further, since the oil pump drive device 13 can drive the oil pump 12 even when the hydraulic oil has a high viscosity, the hydraulic oil can be circulated in the hydraulic system, and the temperature of the hydraulic oil can be increased. It can encourage a rise.

  Further, since the oil temperature sensor 27 is used as a means for detecting the viscosity of the hydraulic oil, the oil temperature sensor 27 already installed in the vehicle 1 can be used. Therefore, a configuration for separately detecting the viscosity of the hydraulic oil. There is no need to add parts. Thereby, the increase in apparatus cost can be suppressed.

  Furthermore, when the engine speed is equal to or higher than the set speed, the oil pump drive device 13 can switch to the low speed drive path 20. In other words, when the discharge amount of the hydraulic oil discharged from the oil pump 12 is excessive, the oil pump 12 operates at a low rotation speed by switching to the low rotation drive path 20, so that the discharge amount of the hydraulic oil is reduced. Can do. On the other hand, when the rotational speed is less than the set rotational speed, the oil pump drive device 13 can switch to the high rotational drive path 21. In other words, when the discharge amount of the hydraulic oil discharged from the oil pump 12 is insufficient, the oil pump 12 operates at a high rotation speed by switching to the high rotation drive path 21, so that the discharge amount of the hydraulic oil is increased. be able to.

  In addition, the oil pump drive device 13 is provided with a one-way clutch 46 between the low-rotation drive path 20 and the input shaft of the oil pump 12, and an electromagnetic clutch 45 between the crankshaft 15 of the engine 5 and the high-rotation drive path 21. By arranging and performing connection control and connection release control of the electromagnetic clutch 45 by the ECU 100, path switching between the low rotation drive path 20 and the high rotation drive path 21 can be selectively performed with simple control and configuration. .

  Further, since the toroidal continuously variable transmission 8 is used as the transmission, even if the hydraulic oil used in the toroidal continuously variable transmission 8 has a high viscosity at low temperatures, the oil pump drive device 13 The pump 12 can be suitably operated.

  In the first embodiment, the temperature of the hydraulic oil is detected by the oil temperature sensor 27 provided in the engine 5, but an oil temperature sensor may be separately provided around the oil pump 12. According to this, the temperature of the hydraulic oil around the oil pump 12 can be accurately detected. In the first embodiment, the oil temperature sensor 27 is used as a means for detecting the viscosity of the hydraulic oil. However, the present invention is not limited to this, and a cooling water temperature sensor that detects the temperature of the cooling water of the engine 5 may be used. Alternatively, the path switching control may be performed based on the elapsed time from the engine start using a timer.

  Next, an oil pump driving device 130 according to the second embodiment will be described with reference to FIG. Only different parts will be described to avoid redundant description. FIG. 4 is a schematic configuration diagram of an oil pump drive device according to the second embodiment. The oil pump drive device 130 according to the second embodiment includes the engine 5, the power transmission path 131 that can transmit the output of the engine 5 to the oil pump 12, and the power transmission path 131 and the oil pump 12. The planetary gear mechanism 132 is provided. The planetary gear mechanism 132 is controlled to be switched by the ECU 100. Note that a series of controls of the oil pump drive device 130 according to the second embodiment are the same as those in the first embodiment, and thus description thereof is omitted.

  An output gear 140 is disposed on the crankshaft 15 of the engine 5. Further, an oil temperature sensor 27 and a crank angle sensor 28 are provided inside the engine 5 as in the first embodiment.

  The oil pump 12 has an input shaft 40, an output shaft 141 of the planetary gear mechanism 132 is connected to the input shaft 40, and an input gear 143 is disposed on the input shaft 142 of the planetary gear mechanism 132. ing.

  The power transmission path 131 has an upstream side connected to an output gear 140 provided on the crankshaft 15 of the engine 5, and a downstream side connected to an input gear 143 provided on the input shaft 142 of the planetary gear mechanism 132.

  The planetary gear mechanism 132 includes an input shaft 142, a sun gear 150 disposed on the input shaft 142 and on the oil pump side of the input gear 143, a plurality of planetary gears 151 meshing with the outer periphery of the sun gear 150, A plurality of planetary gears 151 that mesh with the inner periphery. The ring gear 152 is connected to a switching carrier 155 provided on the input gear 143 side, and the plurality of planetary gears 151 are connected to an output carrier 156 provided on the oil pump 12 side. An output shaft 141 connected to the input shaft 40 of the oil pump 12 is connected to the output carrier 156. The planetary gear mechanism 132 is provided with an electromagnetic clutch 160 and a one-way clutch 161.

  The electromagnetic clutch 160 is a well-known one, and is disposed on the input shaft 142 of the planetary gear mechanism 132 and is interposed between the input gear 143 and the sun gear 150, and the inside of the switching carrier 155. And a clutch brake 164 provided so as to face the clutch plate 163. Thus, the electromagnetic clutch 160 connects and disconnects the input shaft 142 of the planetary gear mechanism 132 and the switching carrier 155. Further, the electromagnetic clutch 160 is connected to the ECU 100, and the switching operation by the ECU 100 causes the electromagnetic clutch 160 to perform a coupling operation or a coupling release operation.

  The one-way clutch 161 is a known one, and its outer peripheral end is attached to a frame (not shown) and its inner peripheral end is attached to the end of the switching carrier 155. As a result, the one-way clutch 161 allows the switching carrier 155 to rotate in the forward direction and restricts rotation in the reverse direction.

  Therefore, when the electromagnetic clutch 160 of the planetary gear mechanism 132 is in the disengaged state, a part of the driving force output from the engine 5 passes through the output gear 140, the power transmission path 131, and the input gear 143, and the planetary gear. Input to the input shaft 142 of the mechanism 132. Thereby, when the input shaft 142 rotates in the forward direction, the sun gear 150 rotates in the forward direction, and the plurality of planetary gears 151 revolve in the forward direction while rotating in the reverse direction. At this time, the ring gear 152 tries to rotate in the reverse direction, but the one-way clutch 161 restricts the rotation in the reverse direction. When the plurality of planetary gears 151 revolve in the forward direction, the output carrier 156 rotates in the forward direction, thereby driving the oil pump 12 via the output shaft 141. At this time, the rotational speed of the sun gear 150 (input shaft 142) is reduced as compared with the rotational speed of the output carrier 156 (output shaft 141) through the plurality of planetary gears 151. That is, when the electromagnetic clutch 160 is in the disengaged state, the oil pump drive device 130 becomes a low rotation drive path. As a result, the oil pump driving device 130 can increase the output torque of the engine 5, so that the oil pump 12 can be driven even when the hydraulic oil has a high viscosity.

  On the other hand, when the electromagnetic clutch 160 of the planetary gear mechanism 132 is in the connected state, a part of the driving force output from the engine 5 passes through the output gear 140, the power transmission path 131 and the input gear 143, and the planetary gear mechanism. 132 is input to the input shaft 142. When the input shaft 142 rotates in the forward direction, since the electromagnetic clutch 160 is connected, the ring gear 152 rotates together with the input shaft 142 in the forward direction. At this time, since the ring gear 152 rotates in the forward direction, the one-way clutch 161 allows the ring gear 152 to rotate. When the input shaft 142 and the ring gear 152 are rotated together, the plurality of planetary gears 151 are also rotated together. The output carrier 156 rotates in the forward direction and drives the oil pump 12 via the output shaft 141. At this time, the rotation speed of the input shaft 142 is the same as the rotation speed of the output shaft 141 because the input shaft 142 and the ring gear 152 rotate together. That is, when the electromagnetic clutch 160 is in the connected state, the oil pump drive device 130 becomes a high rotation drive path. As a result, the oil pump drive device 130 can operate the oil pump 12 at a high speed, and therefore, the oil pump 12 can be driven in a state where the discharge amount of the hydraulic oil is increased.

  According to the above configuration, the planetary gear mechanism 132 can be integrated with the low rotation drive path, the high rotation drive path, and the path switching mechanism. Therefore, the device configuration of the oil pump drive device 130 can be simplified, and the low-rotation drive route or the high-rotation drive route can be obtained by connecting and disconnecting the electromagnetic clutch 160 based on the temperature of the hydraulic oil. It can be switched selectively.

  As described above, the present invention is useful when driving the oil pump when the hydraulic oil has a high viscosity, and is particularly suitable for supplying hydraulic oil to a vehicle engine, a transmission, or the like. .

It is a schematic block diagram of the drive system of the vehicle carrying the oil pump drive device which concerns on Example 1. FIG. 1 is a schematic configuration diagram of an oil pump drive device according to Embodiment 1. FIG. It is a flowchart which concerns on a series of control of an oil pump drive device. FIG. 6 is a schematic configuration diagram of an oil pump drive device according to a second embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle 5 Engine 6 Torque converter 8 Toroidal-type continuously variable transmission 12 Oil pump 13 Oil pump drive device (Example 1)
DESCRIPTION OF SYMBOLS 15 Crankshaft 20 Low rotation drive path 21 High rotation drive path 25 Path switching mechanism 27 Oil temperature sensor 28 Crank angle sensor 35 Output gear 40 Input shaft 43 Input gear 45 Electromagnetic clutch 46 One-way clutch 100 ECU
105 Oil temperature switching control unit 106 Rotational speed switching control unit 107 Engine start switching control unit 130 Oil pump driving device (Example 2)
131 Power transmission path 132 Planetary gear mechanism 140 Output gear (Example 2)
141 Output shaft of planetary gear mechanism 142 Input shaft of planetary gear mechanism 143 Input gear (Example 2)
150 Sun Gear 151 Planetary Gear 152 Ring Gear 155 Switching Carrier 156 Output Carrier 160 Electromagnetic Clutch (Embodiment 2)
161 One-way clutch (Example 2)

Claims (13)

An engine as a drive source of an oil pump capable of discharging hydraulic oil;
A high rotation drive path capable of transmitting the rotation of the engine to the oil pump;
A low-rotation drive path configured to transmit the rotation of the engine to the oil pump and have a reduction ratio larger than that of the high-rotation drive path;
A path switching means capable of selectively switching a path between the high rotation drive path and the low rotation drive path;
Hydraulic oil viscosity detecting means capable of detecting the viscosity of the hydraulic oil;
Switching control means for switching and controlling the path switching means based on the detected viscosity of the hydraulic oil,
The switching control unit switches to the low rotation driving path if the detected viscosity of the hydraulic oil is equal to or higher than a predetermined viscosity, and on the other hand, if the detected hydraulic oil viscosity is less than the predetermined viscosity, the high rotation speed An oil pump drive device characterized by switching to a drive path.   The predetermined viscosity is a threshold value for determining whether or not the oil pump can be operated based on the output torque of the engine transmitted through the high rotation drive path. The oil pump drive device according to claim 1.   3. The oil pump drive device according to claim 1, wherein the switching control unit performs path switching by the path switching unit before starting the engine. 4. The hydraulic oil viscosity detection means includes an oil temperature detection means capable of detecting the temperature of the hydraulic oil, and the switching control means performs switching control of the path switching means based on the detected temperature of the hydraulic oil. Oil temperature switching control means
When the detected temperature of the hydraulic oil is lower than a preset temperature, the oil temperature switching control unit switches to the low rotation drive path, while the detected temperature of the hydraulic oil is the preset temperature. 4. The oil pump drive device according to claim 1, wherein the oil pump drive device is switched to the high rotation drive path in the case of the above.   The oil pump drive device according to claim 4, wherein the set temperature is a threshold value for determining whether the viscosity of the hydraulic oil is equal to or higher than a predetermined viscosity or lower than a predetermined viscosity.   The oil pump drive according to any one of claims 1 to 5, wherein the switching control means further includes an engine start switching control means for switching to the high rotation drive path after the engine is started. apparatus. The engine further comprises an engine speed detecting means for detecting the engine speed, and the switching control means has a speed switching control means for switching the path switching means based on the detected engine speed. ,
The rotation speed switching control means switches to the low rotation drive path when the detected engine rotation speed is equal to or higher than a preset rotation speed, while the detected engine rotation speed is the set rotation speed. The oil pump drive device according to any one of claims 1 to 6, wherein when the number is less than the number, the high-rotation drive path is switched.   The oil pump drive according to claim 7, wherein the set rotational speed is a threshold value for determining whether or not the required discharge amount required for the oil pump can be discharged. apparatus.   The oil pump drive device according to claim 7 or 8, wherein the rotation speed switching control means performs path switching by the path switching means after the engine is started. The route switching means is
A first switching means capable of switching between a power transmission state connecting the high rotation drive path and the oil pump and a power non-transmission state cutting the high rotation drive path and the oil pump;
A second switching means capable of switching between a power transmission state connecting the low rotation drive path and the oil pump and a power non-transmission state cutting the low rotation drive path and the oil pump; The oil pump drive device according to any one of claims 1 to 9, wherein the oil pump drive device is provided.   The oil pump drive device according to claim 10, wherein the first switching unit is an electromagnetic clutch.   The oil pump driving device according to claim 10 or 11, wherein the second switching means is a one-way clutch.   The oil pump drive device according to any one of claims 1 to 12, wherein the high rotation drive path, the low rotation drive path, and the path switching unit are configured by a planetary gear mechanism.