US20010045221A1 - Hydraulic circuit cleaning apparatus and method - Google Patents
Hydraulic circuit cleaning apparatus and method Download PDFInfo
- Publication number
- US20010045221A1 US20010045221A1 US09/861,515 US86151501A US2001045221A1 US 20010045221 A1 US20010045221 A1 US 20010045221A1 US 86151501 A US86151501 A US 86151501A US 2001045221 A1 US2001045221 A1 US 2001045221A1
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- Prior art keywords
- oil
- passage
- hydraulic circuit
- discharge
- pressure regulator
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H57/00—General details of gearing
- F16H57/04—Features relating to lubrication or cooling or heating
- F16H57/0408—Exchange, draining or filling of transmission lubricant
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H57/00—General details of gearing
- F16H57/04—Features relating to lubrication or cooling or heating
- F16H57/0402—Cleaning of lubricants, e.g. filters or magnets
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H57/00—General details of gearing
- F16H57/04—Features relating to lubrication or cooling or heating
- F16H57/048—Type of gearings to be lubricated, cooled or heated
- F16H57/0487—Friction gearings
- F16H57/0489—Friction gearings with endless flexible members, e.g. belt CVTs
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/0021—Generation or control of line pressure
Definitions
- the present invention relates to a cleaning apparatus and a cleaning method for removing foreign substances from a hydraulic circuit.
- the hydraulic control apparatus includes a hydraulic circuit provided with oil passages for supplying and discharging oil pressure with respect to operation mechanisms of the automatic transmission, and various valves for controlling the opening and closing of the oil passages and the oil pressure in the oil passages.
- the electronic control apparatus is formed by a microcomputer. Various kinds of data are pre-stored in the electronic control apparatus.
- the electronic control apparatus is designed so that signals from various sensors and switches are inputted to the electronic control apparatus.
- the electronic control apparatus makes determinations regarding the control of the transmission speed ratio based on the signals from the various sensors and switches and the aforementioned data, and outputs a control signal based on a result of the determination to the hydraulic control apparatus.
- the supplying/discharging of oil pressure with respect to the operational mechanisms and the oil pressure supplied thereto are controlled so as to control the speed ratio of the automatic transmission.
- the oil pressure supplied to the hydraulic circuit is generated by a pressure regulator device regulating the pressure ejected from an oil pump.
- a hydraulic circuit as mentioned above is formed by a component part termed a “valve body”.
- a valve body is mounted between an oil pan and a casing forming an outer shell of the automatic transmission.
- the hydraulic circuit is usually cleaned since there is a possibility of contamination of an interior of the hydraulic circuit with foreign substances.
- Japanese Patent Application Laid-Open No. HEI 10-37734 describes an example of the method for cleaning an oil supplying apparatus and a lubricant supplying apparatus used in a lubrication system of an electric power generating steam turbine, an electric power generator, etc.
- This laid-open patent application describes a normal-use oil pump provided in an oil tank, two oil coolers, and six nozzles that are opened and closed by an oilcooler switching valve.
- the patent application further describes a flushing oil pump connected to a circuit of the oil tank, and a plurality of valves for opening and closing an oil passage between the circuit and the flushing pump.
- Oil supplied from the normal-use oil pump is supplied to an inlet of one of the two oil coolers, and is thereby cooled. After that, oil is discharged from an outlet of the oil cooler, and is delivered to a bearing supply line. Furthermore, using oil ejected from the flushing oil pump, the oil passage in the oil tank can be cleaned.
- the method of cleaning an oil supplying apparatus described in the aforementioned patent application is one in which an oil passage provided in the oil tank is flushed.
- the patent application does not describe the cleaning of a hydraulic circuit that includes an oil pump and apressure regulating device.
- the invention has been accomplished in view of the aforementioned circumstances.
- the invention provides an apparatus and a method for cleaning hydraulic circuit which are capable of cleaning a hydraulic circuit that is provided with an oil pump, a pressure regulator device, etc.
- a hydraulic circuit cleaning apparatus in accordance with a first mode of the invention includes a hydraulic circuit, and a discharge passage that discharges from the hydraulic circuit a cleaning liquid provided for cleaning the hydraulic circuit.
- the hydraulic circuit includes an oil pump, an oil passage to which an oil pressure ejected from the oil pump is supplied, and a pressure regulator device that is connected to the oil passage and that regulates the oil pressure in the oil passage.
- the discharge passage is connected to a discharge port of the pressure regulator device, and discharges the cleaning liquid out of the hydraulic circuit.
- the cleaning liquid when the cleaning liquid is delivered into the oil passage of the hydraulic circuit, the cleaning liquid is discharged into the discharge oil passage via the discharge port of the pressure regulator device. Then, the cleaning liquid is discharged from the discharge oil passage via the discharge passage. Therefore, the cleaning liquid containing foreign substances is not returned to the hydraulic circuit. Therefore, the interior of the hydraulic circuit can be cleaned by utilizing the discharge oil passage connected to the pressure regulator device.
- the above-described cleaning apparatus may further include a lid member that closes the discharge passage after the hydraulic circuit is cleaned with the cleaning liquid.
- the cleaning apparatus of the first mode may be constructed so that the oil pressure discharged from the discharge port of the pressure regulator device is supplied to the suction opening of the oil pump when the oil pump sucks the oil, provided that the discharge passage is closed with the lid member after the hydraulic circuit has been cleaned.
- a hydraulic circuit cleaning apparatus in accordance with a second mode of the invention includes a hydraulic circuit, and a discharge passage that discharges from the hydraulic circuit a cleaning liquid for cleaning the hydraulic circuit.
- the hydraulic circuit includes an oil pump, a circulating oil passage, and a pressure regulator device disposed in the circulating oil passage for regulating the oil pressure in the oil passage.
- the discharge passage is connected between the pressure regulator device in the circulating oil passage and the suction opening of the oil pump, and discharges the cleaning liquid out of the hydraulic circuit.
- the cleaning liquid when the cleaning liquid is delivered into the oil passage of the hydraulic circuit, the cleaning liquid is delivered to the circulating oil passage, and is discharged from the discharge passage via the pressure regulator device. Therefore, the cleaning liquid contaminated with foreign substances will not be returned into the hydraulic circuit. Hence, the interior of the hydraulic circuit can be cleaned by simply utilizing the discharge oil passage connected to the pressure regulator device.
- the cleaning apparatus of the second mode may further include a sealing member that closes the discharge passage, and the hydraulic circuit may further include a filtering device that filters oil sucked into the suction opening of the oil pump.
- the filtering device may be constructedso as to also perform the function of preventing the plug from falling apart. In that case, it is unnecessary to provide a separate member for preventing the plug from falling apart.
- the hydraulic circuit includes an oil pump, an oil passage connected to a suction port of the oil pump, a pressure regulator device that is connected to the oil passage and that regulates the oil pressure in the oil passage, and a discharge oil passage connecting a discharge port of the pressure regulator device and the suction port of the oil pump, and the cleaning liquid used to clean the hydraulic circuit is discharged via the discharge oil passage.
- the cleaning liquid used to clean the hydraulic circuit is discharged out of the hydraulic circuit via the discharge oil passage. Therefore, the method prevents the cleaning liquid contaminated with foreign substances from circulating in the hydraulic circuit. Hence, the method makes it possible to clean the interior of the hydraulic circuit by using the discharge oil passage connected to the pressure regulator device.
- FIG. 1 is a schematic diagram illustrating a portion of a hydraulic circuit of a belt-type continuously variable transmission to which the invention is applied;
- FIG. 2 is a skeleton diagram illustrating a power transmission path of an FF vehicle to which the invention is applied;
- FIG. 3 is a block diagram illustrating a control system of the vehicle shown in FIG. 2;
- FIG. 4 is an exploded perspective view of some of the components of atransaxle shown in FIG. 2;
- FIG. 5 is a sectional view more specifically illustrating the construction shown in FIG. 1;
- FIG. 6 is a schematic diagram illustrating acleaning method of a hydraulic circuit to which the invention is applied.
- FIG. 7 is a schematic diagram of still another construction of an hydraulic circuit to which the invention is applied.
- FIG. 2 is a skeleton diagram showing a front-engine, front-drive vehicle to which this invention is applied.
- an engine 1 is installed as a power source for a vehicle.
- An internal combustion engine more particularly a gasoline engine, diesel engine, oran LPG engine, may used as the engine 1 .
- a crankshaft 2 of the engine 1 is disposed in the width direction of the vehicle.
- a gasoline engine is used as the engine 1 .
- a transaxle 3 is provided on the output side of the engine 1 .
- the transaxle 3 has a transaxle housing 4 , a transaxle case 5 , and a transaxle cover 6 .
- the transaxle housing 4 is attached to the rear end of the engine 1 .
- the transaxle case 5 is mounted on the end of an opening in the transaxle housing 4 opposite the engine 1 .
- the transaxle cover 6 is mounted on the end of an opening in the transaxle case 5 opposite the transaxle housing 4 .
- a valve body unit and an oil pan are attached to a lower portion of the transaxle case 5 .
- a torque converter 7 is provided inside the transaxle housing 4 .
- a forward-reverse selection mechanism 8 , variable belt transmission (CVT) 9 , and a final reduction gear (in other words, a differential gear system) 10 are provided inside the transaxle case 6 and the transaxle rear cover 6 .
- the construction of the torque converter 7 will first be described.
- An input shaft 11 that can rotate about the same axis as the crankshaft 2 is provided in the transaxle housing 4 .
- a turbine runner 13 is mounted on the end of the input shaft 11 on the side of the engine 1 .
- a front cover 15 is communicated via a drive plate 14 to the rear end of the crankshaft 2 and a pump impeller 15 is connected to the front cover 15 .
- the turbine runner 13 and the pump impeller 16 are disposed opposing one another and a stator 17 is provided inside the turbine runner 13 and the pump impeller 16 .
- a hollow shaft 17 B is connected by way of a one-way clutch 17 A to the stator 17 .
- the input shaft 11 runs through this hollow shaft 17 B.
- a lockup clutch 19 is provided via a damper mechanism 18 on the end of the input shaft 11 on the side of the front cover 15 . Oil as a hydraulic fluid is supplied to the inside of a casing (not shown) formed by the front cover 15 , pump impeller 16 , and other components as noted above.
- An oil pump 20 is provided between the torque converter 7 and the forward-reverse selection mechanism 8 .
- a rotor 21 of the oil pump 20 and the pump impeller 16 are connected by a hub 22 of cylindrical shape.
- a body 23 of the oil pump 20 is secured to a side of the transaxle case 5 .
- the hub 22 and the hollow shaft 17 B are in splined engagement with each other. This configuration allows power from the engine 1 to be transmitted via the pump impeller 16 to the rotor 21 , thus driving the oil pump 20 .
- the forward-reverse selection mechanism 8 is provided along a power transmission path between the input shaft 11 and the variable belt transmission 9 .
- the forward-reverse selection mechanism 8 is provided with a planetary gear mechanism 24 of a double-pinion type.
- the planetary gear mechanism 24 comprises a sun gear 25 provided on the end of the input shaft 11 on the side of the variable belt transmission 9 , a ring gear 26 disposed concentrically with the sun gear 25 on an outer peripheral side of the sun gear 25 , a pinion gear 27 that is meshed with the sun gear 25 , a pinion gear 28 that is meshed with the pinion gear 27 and the ring gear 26 , and a carrier 29 which rotatably retains the pinion gears 27 and 28 , as well as retains the pinion gears 27 and 28 so that they can rotate integrally around the sun gear 25 .
- the carrier 29 is connected to a primary shaft (to be described later) of the input shaft 11 .
- a forward clutch CR which connects and disconnects a power transmission path between the carrier 29 and the input shaft 11 , is provided.
- a reverse brake BR which controls rotation and lockup of the ring gear 26 , is provided on a side of the transaxle case 5 .
- the variable belt transmission 9 is provided with a primary shaft 30 disposed concentrically with the input shaft 11 (in other words, a shaft on the drive side) and a secondary shaft 31 disposed in parallel with the primary shaft 30 (in other words, a countershaft or a shaft on the driven side). Bearings 32 and 33 rotatably retain the primary shaft 30 and bearings 34 and 35 rotatably retain the secondary shaft 31 .
- the primary shaft 30 is provided with a primary pulley 36 and the secondary shaft 31 is provided with a secondary pulley 37 .
- the primary pulley 36 is provided with a fixed sheave 38 (in other words, a fixed member) formed integrally with the primary shaft 30 on its periphery and a movable sheave 39 (in other words, a movable member) configured so as to be movable in an axial direction of the primary shaft 30 .
- a V-shaped groove 40 is formed between opposing faces of the fixed sheave 38 and the movable sheave 39 .
- a hydraulic actuator 41 (in other words, a hydraulic servo mechanism) that causes the movable sheave 39 to approach and separate from the fixed sheave 38 by moving the movable sheave 39 in the axial direction of the primary shaft 30 is provided.
- the secondary pulley 37 is provided with a fixed sheave 42 (in other words, a fixed member) formed integrally with the secondary shaft 31 on the periphery thereof and a movable sheave 43 (in other words, a movable member) configured so as to be movable in an axial direction of the secondary shaft 31 .
- a V-shaped groove 44 is formed between opposing faces of the fixed sheave 42 and the movable sheave 43 .
- a hydraulic actuator 45 (in other words, a hydraulic servo mechanism) that causes the movable sheave 43 to approach and separate from the fixed sheave 42 by moving the movable sheave 43 in the axial direction of the secondary shaft 31 is provided.
- a belt 46 is wound around the groove 40 of the primary pulley 36 and the groove 44 of the secondary pulley 37 in the configuration.
- the belt 46 is provided with multiple metal blocks and a plurality of steel rings.
- a counter driven gear 47 of a cylindrical shape is secured to the secondary shaft 31 on the side of the engine 1 and the counter driven gear 47 is retained by bearings 48 and 49 .
- the bearing 35 is provided on the side of the transaxle rear cover 6 and a parking gear 31 A is provided on the secondary shaft 31 between the bearing 35 and the secondary pulley 37 .
- An intermediate shaft 50 that is parallel with the secondary shaft 31 is provided along a power transmission path between the counter driven gear 47 and the final reduction gear 10 of the variable belt transmission 9 .
- the intermediate shaft 50 is supported by bearings 51 and 52 .
- a counter driven gear 53 and a final drive gear 54 are formed on the intermediate shaft 50 .
- the counter drive gear 47 is meshed with the counter driven gear 53 .
- the final reduction gear 10 is provided with a hollow differential case 55 .
- the differential case 55 is rotatably retained by bearings 56 and 57 and a ring gear 58 is provided on an outer periphery of the differential case 55 .
- the final drive gear 54 is meshed with the ring gear 58 .
- a pinion shaft 59 is mounted inside the differential case 55 and two pinion gears 60 are mounted on the pinion shaft 59 .
- Two side gears 61 are meshed with these pinion gears 60 .
- a front drive shaft 62 is connected independently to each of the two side gears 61 and a wheel (front wheel) 63 is connected to each of these front drive shafts 62 .
- FIG. 3 is a block diagram showing a control system of the vehicle shown in FIG. 2.
- An electronic control unit 64 that controls the entire vehicle is made up of a microprocessor comprising mainly a computer processing unit (CPU or MPU), storage devices (RAM and ROM), and an I/O interface.
- CPU or MPU computer processing unit
- RAM and ROM storage devices
- I/O interface I/O interface
- Signals are input to this electronic control unit 64 from such devices as an engine speed sensor 65 , an accelerator opening sensor 66 , a throttle opening sensor 67 , a brake switch 68 , a shift position sensor 69 that detects the operating condition of a shift position selection unit 69 A, an input speed sensor 70 that detects the input speed of the variable belt transmission 9 , an output speed sensor 71 that detects the output speed of the variable belt transmission 9 , an oil temperature sensor 72 that detects the hydraulic fluid temperature of the variable belt transmission 9 and the torque converter 7 , an air conditioner switch 73 , and a coolant temperature sensor 74 that detects coolant temperature of the engine 1 .
- an engine speed sensor 65 an accelerator opening sensor 66 , a throttle opening sensor 67 , a brake switch 68 , a shift position sensor 69 that detects the operating condition of a shift position selection unit 69 A
- an input speed sensor 70 that detects the input speed of the variable belt transmission 9
- an output speed sensor 71 that detects the output speed of the variable
- the signal fed from the shift position sensor 69 is used to determine which is selected, either a drive position [for example, D (drive) position, R (reverse) position, etc.] or a non-drive position [for example, N (neutral) position, P (park) position, etc.]. It is further used to determine which is selected of the two drive positions, either a forward position (for example, D position) or a reverse position (R position). Furthermore, a vehicle speed and a gear ratio of the variable belt transmission 9 can be calculated by using a signal from the engine speed sensor 65 , a signal from the input speed sensor 70 , and a signal from the output speed sensor 71 and the like.
- the electronic control unit 64 outputs a signal that controls a fuel injection control unit 75 of the engine 1 , a signal that controls an ignition timing control unit 76 of the engine 1 , and a signal that controls a hydraulic pressure control unit 77 .
- a construction of the hydraulic pressure control unit 77 will be described.
- FIG. 4 is an exploded view of some of the component parts of the transaxle 3 .
- An oil pan 80 is attached to a lower portion of the transaxle case 5 .
- a valve body unit 84 formed by integrally assembling an upper valve body 81 , a plate 82 and a lower valve body 83 are provided between the transaxle case 5 and the oil pan 80 .
- the valve body unit 84 forms a hydraulic circuit.
- FIG. 1 is a schematic diagram illustrating a portion of a hydraulic circuit 85 formed by the valve body unit 84 .
- FIG. 5 is a sectional view of specific component parts forming the hydraulic circuit 85 shown in FIG. 1.
- a strainer 87 is provided in a path extending from the oil pan 80 to a suction opening 86 of the oil pump 20 .
- a construction for mounting the strainer 87 will be specifically described.
- a passage 101 is formed in the lower valve body 83 . The passage 101 connects to the side of the suction opening 86 .
- the strainer 87 is formed by disposing two divisions 87 A, 87 B in a vertical positional relationship and integrally joining the divisions.
- a division 87 A is disposed above the other division 87 B.
- the division 87 A has a cylindrical ejection portion 102 that is protruded toward the lower valve body 83 .
- a cylindrical suction portion 102 A is protruded toward the oil pan 80 .
- An outer peripheral surface of the ejection portion 102 is fitted to an inner peripheral surface of the passage 101 . Due to this fitting force, the strainer 87 is secured to the lower valve body 83 .
- An O-ring 103 is attached to an outer periphery of the ejection portion 102 , thus providing a liquid-tight seal between the ejection portion 102 and the lower valve body 83 .
- An oil transportation path 20 A connecting the suction opening 86 and an ejection opening 88 is formed in the oil pump 20 .
- An oil passage 89 is connected to the ejection opening 88 .
- the oil passage 89 is also connected to an oil chamber (not shown) of a hydraulic actuator 41 .
- the hydraulic circuit 85 is also provided with a pressure regulator valve 90 .
- the pressure regulator valve 90 has a pressure regulation port 91 and a discharge port 92 .
- An oil passage 89 A branching from an intermediate portion of the oil passage 89 is connected to the pressure regulation port 91 .
- the pressure regulator valve 90 has a known construction provided with a spool (not shown), a spring (not shown), etc.
- the pressure regulator valve 90 is used for controlling the oil pressure at the ejection side of the pressure regulator valve 90 .
- the pressure regulation port 91 and the hydraulic actuator 41 are disposed in parallel.
- a discharge oil passage (in other words, a relief oil passage or a circulating oil passage) 93 is formed connecting the discharge port 92 and the suction opening 86 of the oil pump 20 .
- the discharge oil passage 93 is provided with a cleaning liquid discharge passage 95 that connects to the side of the oil pan 80 .
- the cleaning liquid discharge passage 95 extends substantially vertically through the lower valve body 83 .
- the cleaning liquid discharge passage 95 is formed above the strainer 87 .
- a plug 96 is provided for opening and closing the cleaning liquid discharge passage 95 .
- the plug 96 has a shaft portion 97 and a head portion 98 .
- An O-ring 99 is attached to an outer periphery of the shaft portion 97 .
- the shaft portion 97 of the plug 96 is fitted into the cleaning liquid discharge passage 95 from the side of the oil pan 80 .
- the strainer 87 contacts a lower surface of the head portion 98 of the plug 96 fitted to the lower valve body 83 .
- the valve body unit 84 has a solenoid valve (not shown) for controlling the engagement and disengagement of the lockup clutch 19 , a solenoid valve (not shown) for controlling the oil pressure supplied and discharged with respect to the oil chambers of the hydraulic actuators 41 , 45 , a solenoid (not shown) for controlling the oil pressure that acts on the forward clutch CR and the reverse brake BR, etc.
- the hydraulic circuit 85 is further provided with an oil passage (not shown) that connects to the hydraulic actuator 45 .
- Data used for providing a transmission control of the engine 1 , lockup clutch 19 , and the variable belt transmission 9 based on the various signals are stored in the electronic control unit 64 .
- the electronic control unit 64 stores data, with which an optimum operating condition of the engine 1 is selected by controlling the gear ratio of the variable belt transmission 9 based on the accelerator opening, vehicle speed, and other vehicle operating conditions.
- the electronic control unit 64 also stores a lockup clutch control map having the accelerator opening and vehicle speed as parameters.
- the lockup clutch 19 is controlled through each state of engagement, disengagement, and slip based on this lockup clutch control map.
- the electronic control unit 64 outputs control signals to the fuel injection control unit 75 , the ignition timing control unit 76 , and the hydraulic pressure control unit 77 based on the various signals input to the electronic control unit 64 and the data stored in the electronic control unit 64 .
- the oil passage 89 corresponds to an oil passage in the invention.
- the pressure regulator valve 90 corresponds to a pressure regulator device in the invention.
- the plug 96 corresponds to a lid member and a sealing device in the invention.
- the oil passage 89 , 89 A and the discharge oil passage 93 correspond to a circulating oil passage in the invention.
- the strainer 87 corresponds to a filtering device in the invention.
- the forward-reverse selection mechanism 8 is controlled based on operation of the shift position selection unit 69 A.
- the forward clutch CR is engaged and the reverse brake BR is released, which results in the input shaft 11 being directly connected to the primary shaft 30 .
- the torque (or power) of the engine 1 is transmitted via the torque converter 7 to the input shaft 11 in this state, the input shaft 11 , carrier 29 , and the primary shaft 30 turn integrally.
- the torque of the primary shaft 30 is transmitted via the primary pulley 36 , the belt 46 , and the secondary pulley 37 to the secondary shaft 31 .
- the torque transmitted to the secondary shaft 31 is transmitted to the intermediate shaft 50 by way of the counter drive gear 47 and the counter driven gear 53 .
- the torque transmitted to the intermediate shaft 50 is transmitted to the differential case 55 by way of the final drive gear 54 and the ring gear 58 .
- the differential case 55 turns, its torque is transmitted to the drive shaft 62 by way of the pinion gear 60 and the side gear 61 , and then transmitted to the wheel 63 .
- the gear ratio of the variable belt transmission 9 is controlled so that the operating conditions of the engine 1 may be optimized based on vehicle acceleration requirements evaluated with the vehicle speed, accelerator opening, and other conditions (namely, drive power requirements), data stored in the electronic control unit 64 (for example, an optimum fuel consumption curve having the engine speed and throttle opening as parameters), and other factors.
- the width of the groove 40 in the primary pulley 36 is varied by controlling the hydraulic pressure of the hydraulic chamber of the hydraulic actuator 41 .
- the winding radius of the belt 4 of the primary pulley 36 is changed, which means that the ratio of the input speed to the output speed of the variable belt transmission 9 , namely the gear ratio, is controlled steplessly (continuously).
- the width of the groove 44 of the secondary pulley 37 is changed. That is, the clamping pressure (i.e., clamping force) of the secondary pulley 37 on the belt 31 in the direction of the axis thereof is controlled. Based on the clamping pressure, the tension of the belt 31 is controlled so that the contact surface pressure between the primary pulley 36 and the belt 31 and between the secondary pulley 37 and the belt 31 is controlled.
- the oil pressure in the oil chamber of the hydraulic actuator 45 is controlled based on the torque input to the variable belt transmission 9 , the speed ratio of the variable belt transmission 9 , etc.
- the torque input to the variable belt transmission 9 is determined based on the engine revolution speed, the degree of throttle opening, the torque ratio of the torque converter 7 , etc.
- a flushing operation of cleaning the hydraulic circuit 85 of the valve body unit 84 is performed to remove foreign substances, for example, waste, dust, or the like, which may be present within the hydraulic circuit 85 .
- an oil pump 100 separate from the oil pump 20 , is provided between the strainer 87 and the oil pan 80 as shown in FIG. 6, and the plug 96 is removed to open the cleaning liquid discharge passage 95 .
- a cleaning liquid (which may be an automatic transmission fluid (ATF) that is the operating fluid of the transaxle 3 ) is supplied from the oil pan 80 into the hydraulic circuit 85 .
- the cleaning liquid is pumped into the oil passage 89 , and the pressure in the oil passage 89 rises to a predetermined pressure.
- the pressure regulator valve 90 via the pressure regulator valve 90 , the pressure regulation port 91 and the discharge port 92 are connected in communication, so that the cleaning liquid is discharged into the discharge oil passage 93 via the discharge port 92 .
- the cleaning liquid discharge passage 95 is opened as mentioned above, the cleaning liquid is discharged from the discharge oil passage 93 into the oil pan 80 via the cleaning liquid discharge passage 95 . Therefore, the cleaning liquid used to remove foreign substances from the hydraulic circuit 85 will not return to the hydraulic circuit 85 . After the cleaning of the hydraulic circuit 85 ends, the cleaning liquid discharge passage 95 is liquid-tightly closed by the plug 96 as shown in FIGS. 1 and 5, and the oil pump 100 is removed.
- the oil pump 20 and the pressure regulator valve 90 can also be cleaned by driving the oil pump 20 and driving the oil pump 100 after mounting the valve body unit 84 and the strainer 87 below the transaxle case 5 .
- the ejection pressure of the oil pump 20 is supplied to the oil passage 89 .
- the oil pressure in the oil passage 89 rises to a predetermined pressure.
- the pressure regulator valve 90 the pressure regulation port 91 and the discharge port 92 are connected in communication, so that oil is discharged from the pressure regulation port 91 into the discharge oil passage 93 via the discharge port 92 . Since the cleaning liquid discharge passage 95 has been closed, the oil pressure in the discharge oil passage 93 is transmitted to the suction opening 86 of the oil pump 20 .
- FIG. 7 illustrates another embodiment of the hydraulic circuit cleaning apparatus and cleaning method, showing a portion of a hydraulic circuit 85 .
- the hydraulic circuit 85 shown in FIG. 7 constructions substantially the same as those of the embodiment shown in FIGS. 1 to 6 are represented by reference characters which are the same as those used in FIGS. 1 to 6 . Such constructions will not be described again.
- the hydraulic circuit 85 has two pressure regulator valves 104 , 108 .
- the pressure regulator valve 104 has a pressure regulation port 105 and a discharge port 106 .
- the pressure regulator valve 108 has a pressure regulation port 109 and a discharge port 110 .
- An oil passage 89 A branching from an oil passage 89 is connected to the pressure regulation port 105 .
- the discharge port 106 and the pressure regulation port 109 are connected by an oil passage 107 .
- the discharge port 110 is connected to the side of a suction opening 86 of an oil pump 20 via a discharge oil passage (i.e., a circulating oil passage a relief oil passage) 93 .
- a discharge oil passage i.e., a circulating oil passage a relief oil passage
- An oil passage 111 connecting the hydraulic actuator 41 and the oil passage 107 is provided.
- the pressure regulator valves 104 , 108 correspond to a pressure regulator device in the invention.
- the oil passages 89 , 89 A, 107 , 93 correspond to a circulating oil passage in the invention.
- the hydraulic circuit 85 of this embodiment achieves substantially the same advantages as those achieved by the hydraulic circuit 85 shown in FIG. 1. Furthermore, after the plug 96 is attached to the hydraulic circuit 85 shown in FIG. 7, the hydraulic circuit 85 achieves substantially the same advantages as those achieved by the hydraulic circuit 85 shown in FIG. 1.
- the flushing operation can be performed after the transaxle 3 is manufactured. Furthermore, after the flushing operation, the suction force of the oil pump 20 is supplemented with the oil pressure in the discharge oil passage 93 , so that the oil suction function of the oil pump 20 improves. That is, it becomes possible to perform the flushing operation in a process after manufacture of the transaxle 3 , without degrading the effect of re-supplying oil pressure to the suction opening 86 of the oil pump 20 (i.e., the super charge effect).
- the strainer 87 when the strainer 87 is secured to the lower valve body 83 after the cleaning liquid discharge passage 95 is closed by the plug 96 , the strainer 87 contacts the head portion 98 of the plug 96 as shown in FIG. 5. That is, the strainer 87 performs both the function of cleaning oil supplied from the side of the oil pan 80 to the side of the strainer 87 and the function of preventing the plug 96 from falling from the lower valve body 83 (generally termed fall-apart preventing function). Therefore, it is unnecessary to separately provide a component part for preventing the plug 96 from falling. Hence, the number of component parts required for the cleaning apparatus is reduced, thereby allowing size and weight reductions of the apparatus and curbing increases in the production cost of the apparatus.
- each embodiment can be used as a hydraulic circuit cleaning apparatus for a hydraulic control apparatus that controls the engagement and disengagement of the friction engagement devices and the engagement pressure for the devices.
- each embodiment can also be used as a hydraulic circuit cleaning apparatus for a hydraulic control apparatus of a toroidal type continuously variable transmission.
- the toroidal type continuously variable transmission refers to a continuously variable transmission having a plurality of cone discs each of which has a power transmission surface of an arcuate shape corresponding to the shape of an outer peripheral surface of a doughnut, and at least one power roller that contacts the power transmission surfaces of the cone discs via a lubricant (traction oil).
- a lubricant traction oil
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Abstract
Description
- The disclosure of Japanese Patent Application No. 2000-150404 filed on May 22, 2000 including the specification, drawings and abstract is incorporated herein by reference in its entirety.
- 1. Field of the Invention
- The present invention relates to a cleaning apparatus and a cleaning method for removing foreign substances from a hydraulic circuit.
- 2. Description of the Related Art
- Generally, in a vehicle equipped with an automatic transmission, a hydraulic control apparatus and an electronic control apparatus are provided. The hydraulic control apparatus includes a hydraulic circuit provided with oil passages for supplying and discharging oil pressure with respect to operation mechanisms of the automatic transmission, and various valves for controlling the opening and closing of the oil passages and the oil pressure in the oil passages. The electronic control apparatus is formed by a microcomputer. Various kinds of data are pre-stored in the electronic control apparatus. The electronic control apparatus is designed so that signals from various sensors and switches are inputted to the electronic control apparatus.
- The electronic control apparatus makes determinations regarding the control of the transmission speed ratio based on the signals from the various sensors and switches and the aforementioned data, and outputs a control signal based on a result of the determination to the hydraulic control apparatus. As a result, the supplying/discharging of oil pressure with respect to the operational mechanisms and the oil pressure supplied thereto are controlled so as to control the speed ratio of the automatic transmission. The oil pressure supplied to the hydraulic circuit is generated by a pressure regulator device regulating the pressure ejected from an oil pump.
- A hydraulic circuit as mentioned above is formed by a component part termed a “valve body”. Such a valve body is mounted between an oil pan and a casing forming an outer shell of the automatic transmission. However, before the valve body is mounted between the casing and the oil pan, the hydraulic circuit is usually cleaned since there is a possibility of contamination of an interior of the hydraulic circuit with foreign substances.
- As an art related to the hydraulic circuit cleaning apparatus as mentioned above, Japanese Patent Application Laid-Open No. HEI 10-37734 describes an example of the method for cleaning an oil supplying apparatus and a lubricant supplying apparatus used in a lubrication system of an electric power generating steam turbine, an electric power generator, etc. This laid-open patent application describes a normal-use oil pump provided in an oil tank, two oil coolers, and six nozzles that are opened and closed by an oilcooler switching valve. The patent application further describes a flushing oil pump connected to a circuit of the oil tank, and a plurality of valves for opening and closing an oil passage between the circuit and the flushing pump. Oil supplied from the normal-use oil pump is supplied to an inlet of one of the two oil coolers, and is thereby cooled. After that, oil is discharged from an outlet of the oil cooler, and is delivered to a bearing supply line. Furthermore, using oil ejected from the flushing oil pump, the oil passage in the oil tank can be cleaned.
- The method of cleaning an oil supplying apparatus described in the aforementioned patent application is one in which an oil passage provided in the oil tank is flushed. However, the patent application does not describe the cleaning of a hydraulic circuit that includes an oil pump and apressure regulating device.
- The invention has been accomplished in view of the aforementioned circumstances. The invention provides an apparatus and a method for cleaning hydraulic circuit which are capable of cleaning a hydraulic circuit that is provided with an oil pump, a pressure regulator device, etc.
- A hydraulic circuit cleaning apparatus in accordance with a first mode of the invention includes a hydraulic circuit, and a discharge passage that discharges from the hydraulic circuit a cleaning liquid provided for cleaning the hydraulic circuit. The hydraulic circuit includes an oil pump, an oil passage to which an oil pressure ejected from the oil pump is supplied, and a pressure regulator device that is connected to the oil passage and that regulates the oil pressure in the oil passage. The discharge passage is connected to a discharge port of the pressure regulator device, and discharges the cleaning liquid out of the hydraulic circuit.
- According to the first mode, when the cleaning liquid is delivered into the oil passage of the hydraulic circuit, the cleaning liquid is discharged into the discharge oil passage via the discharge port of the pressure regulator device. Then, the cleaning liquid is discharged from the discharge oil passage via the discharge passage. Therefore, the cleaning liquid containing foreign substances is not returned to the hydraulic circuit. Therefore, the interior of the hydraulic circuit can be cleaned by utilizing the discharge oil passage connected to the pressure regulator device.
- The above-described cleaning apparatus may further include a lid member that closes the discharge passage after the hydraulic circuit is cleaned with the cleaning liquid.
- If the cleaning liquid discharge passage is closed with the lid member after the hydraulic circuit is cleaned, the oil delivered into the oil passage by the oil pump will not be discharged from the cleaning liquid discharge passage.
- The cleaning apparatus of the first mode may be constructed so that the oil pressure discharged from the discharge port of the pressure regulator device is supplied to the suction opening of the oil pump when the oil pump sucks the oil, provided that the discharge passage is closed with the lid member after the hydraulic circuit has been cleaned.
- A hydraulic circuit cleaning apparatus in accordance with a second mode of the invention includes a hydraulic circuit, and a discharge passage that discharges from the hydraulic circuit a cleaning liquid for cleaning the hydraulic circuit. The hydraulic circuit includes an oil pump, a circulating oil passage, and a pressure regulator device disposed in the circulating oil passage for regulating the oil pressure in the oil passage. The discharge passage is connected between the pressure regulator device in the circulating oil passage and the suction opening of the oil pump, and discharges the cleaning liquid out of the hydraulic circuit.
- According to the second mode, when the cleaning liquid is delivered into the oil passage of the hydraulic circuit, the cleaning liquid is delivered to the circulating oil passage, and is discharged from the discharge passage via the pressure regulator device. Therefore, the cleaning liquid contaminated with foreign substances will not be returned into the hydraulic circuit. Hence, the interior of the hydraulic circuit can be cleaned by simply utilizing the discharge oil passage connected to the pressure regulator device.
- The cleaning apparatus of the second mode may further include a sealing member that closes the discharge passage, and the hydraulic circuit may further include a filtering device that filters oil sucked into the suction opening of the oil pump.
- The filtering device may be constructedso as to also perform the function of preventing the plug from falling apart. In that case, it is unnecessary to provide a separate member for preventing the plug from falling apart.
- In a cleaning method for cleaning a hydraulic circuit in accordance with a third mode of the invention, the hydraulic circuit includes an oil pump, an oil passage connected to a suction port of the oil pump, a pressure regulator device that is connected to the oil passage and that regulates the oil pressure in the oil passage, and a discharge oil passage connecting a discharge port of the pressure regulator device and the suction port of the oil pump, and the cleaning liquid used to clean the hydraulic circuit is discharged via the discharge oil passage.
- According to the third mode, the cleaning liquid used to clean the hydraulic circuit is discharged out of the hydraulic circuit via the discharge oil passage. Therefore, the method prevents the cleaning liquid contaminated with foreign substances from circulating in the hydraulic circuit. Hence, the method makes it possible to clean the interior of the hydraulic circuit by using the discharge oil passage connected to the pressure regulator device.
- The foregoing and further objects, features and advantages of the present invention will become apparent from the following description of preferred embodiments with reference to the accompanying drawings, wherein like numerals are used to represent like elements and wherein:
- FIG. 1 is a schematic diagram illustrating a portion of a hydraulic circuit of a belt-type continuously variable transmission to which the invention is applied;
- FIG. 2 is a skeleton diagram illustrating a power transmission path of an FF vehicle to which the invention is applied;
- FIG. 3 is a block diagram illustrating a control system of the vehicle shown in FIG. 2;
- FIG. 4 is an exploded perspective view of some of the components of atransaxle shown in FIG. 2;
- FIG. 5 is a sectional view more specifically illustrating the construction shown in FIG. 1;
- FIG. 6 is a schematic diagram illustrating acleaning method of a hydraulic circuit to which the invention is applied; and
- FIG. 7 is a schematic diagram of still another construction of an hydraulic circuit to which the invention is applied.
- The preferred embodiments of the invention will hereinafter be described in detail with reference to the attached drawings. FIG. 2 is a skeleton diagram showing a front-engine, front-drive vehicle to which this invention is applied. Referring to FIG. 2, an engine1 is installed as a power source for a vehicle. An internal combustion engine, more particularly a gasoline engine, diesel engine, oran LPG engine, may used as the engine 1. A
crankshaft 2 of the engine 1 is disposed in the width direction of the vehicle. For the sake of convenience, the following description assumes that a gasoline engine is used as the engine 1. - A transaxle3 is provided on the output side of the engine 1. The transaxle 3 has a
transaxle housing 4, atransaxle case 5, and atransaxle cover 6. Thetransaxle housing 4 is attached to the rear end of the engine 1. Thetransaxle case 5 is mounted on the end of an opening in thetransaxle housing 4 opposite the engine 1. Thetransaxle cover 6 is mounted on the end of an opening in thetransaxle case 5 opposite thetransaxle housing 4. A valve body unit and an oil pan are attached to a lower portion of thetransaxle case 5. - A torque converter7 is provided inside the
transaxle housing 4. A forward-reverse selection mechanism 8, variable belt transmission (CVT) 9, and a final reduction gear (in other words, a differential gear system) 10 are provided inside thetransaxle case 6 and the transaxlerear cover 6. The construction of the torque converter 7 will first be described. An input shaft 11 that can rotate about the same axis as thecrankshaft 2 is provided in thetransaxle housing 4. Aturbine runner 13 is mounted on the end of the input shaft 11 on the side of the engine 1. - A
front cover 15 is communicated via adrive plate 14 to the rear end of thecrankshaft 2 and apump impeller 15 is connected to thefront cover 15. Theturbine runner 13 and thepump impeller 16 are disposed opposing one another and a stator 17 is provided inside theturbine runner 13 and thepump impeller 16. A hollow shaft 17B is connected by way of a one-way clutch 17A to the stator 17. The input shaft 11 runs through this hollow shaft 17B. Alockup clutch 19 is provided via adamper mechanism 18 on the end of the input shaft 11 on the side of thefront cover 15. Oil as a hydraulic fluid is supplied to the inside of a casing (not shown) formed by thefront cover 15,pump impeller 16, and other components as noted above. - With this configuration, a power (torque) from the engine1 is transmitted through the
crankshaft 2 to thefront cover 15. If thelockup clutch 19 is disengaged at this time, torque of thepump impeller 16 is transmitted to theturbine runner 13 and then to the input shaft 11 through the fluid. The torque transmitted from thepump impeller 16 to theturbine runner 13 may be amplified by the stator 17. On the other hand, if thelockup clutch 19 is engaged at this time, the torque of thefront cover 15 is mechanically transmitted to the input shaft 11. - An
oil pump 20 is provided between the torque converter 7 and the forward-reverse selection mechanism 8. A rotor 21 of theoil pump 20 and thepump impeller 16 are connected by ahub 22 of cylindrical shape. A body 23 of theoil pump 20 is secured to a side of thetransaxle case 5. Thehub 22 and the hollow shaft 17B are in splined engagement with each other. This configuration allows power from the engine 1 to be transmitted via thepump impeller 16 to the rotor 21, thus driving theoil pump 20. - The forward-reverse selection mechanism8 is provided along a power transmission path between the input shaft 11 and the
variable belt transmission 9. The forward-reverse selection mechanism 8 is provided with aplanetary gear mechanism 24 of a double-pinion type. Theplanetary gear mechanism 24 comprises a sun gear 25 provided on the end of the input shaft 11 on the side of thevariable belt transmission 9, a ring gear 26 disposed concentrically with the sun gear 25 on an outer peripheral side of the sun gear 25, apinion gear 27 that is meshed with the sun gear 25, apinion gear 28 that is meshed with thepinion gear 27 and the ring gear 26, and a carrier 29 which rotatably retains the pinion gears 27 and 28, as well as retains the pinion gears 27 and 28 so that they can rotate integrally around the sun gear 25. The carrier 29 is connected to a primary shaft (to be described later) of the input shaft 11. In addition, a forward clutch CR, which connects and disconnects a power transmission path between the carrier 29 and the input shaft 11, is provided. Further, a reverse brake BR, which controls rotation and lockup of the ring gear 26, is provided on a side of thetransaxle case 5. - The
variable belt transmission 9 is provided with aprimary shaft 30 disposed concentrically with the input shaft 11 (in other words, a shaft on the drive side) and asecondary shaft 31 disposed in parallel with the primary shaft 30 (in other words, a countershaft or a shaft on the driven side).Bearings primary shaft 30 andbearings secondary shaft 31. - The
primary shaft 30 is provided with aprimary pulley 36 and thesecondary shaft 31 is provided with asecondary pulley 37. Theprimary pulley 36 is provided with a fixed sheave 38 (in other words, a fixed member) formed integrally with theprimary shaft 30 on its periphery and a movable sheave 39 (in other words, a movable member) configured so as to be movable in an axial direction of theprimary shaft 30. A V-shapedgroove 40 is formed between opposing faces of the fixedsheave 38 and themovable sheave 39. - Furthermore, a hydraulic actuator41 (in other words, a hydraulic servo mechanism) that causes the
movable sheave 39 to approach and separate from the fixedsheave 38 by moving themovable sheave 39 in the axial direction of theprimary shaft 30 is provided. Meanwhile, thesecondary pulley 37 is provided with a fixed sheave 42 (in other words, a fixed member) formed integrally with thesecondary shaft 31 on the periphery thereof and a movable sheave 43 (in other words, a movable member) configured so as to be movable in an axial direction of thesecondary shaft 31. A V-shaped groove 44 is formed between opposing faces of the fixedsheave 42 and themovable sheave 43. In addition, a hydraulic actuator 45 (in other words, a hydraulic servo mechanism) that causes themovable sheave 43 to approach and separate from the fixedsheave 42 by moving themovable sheave 43 in the axial direction of thesecondary shaft 31 is provided. - A
belt 46 is wound around thegroove 40 of theprimary pulley 36 and the groove 44 of thesecondary pulley 37 in the configuration. Thebelt 46 is provided with multiple metal blocks and a plurality of steel rings. A counter drivengear 47 of a cylindrical shape is secured to thesecondary shaft 31 on the side of the engine 1 and the counter drivengear 47 is retained bybearings bearing 35 is provided on the side of the transaxlerear cover 6 and aparking gear 31A is provided on thesecondary shaft 31 between the bearing 35 and thesecondary pulley 37. - An
intermediate shaft 50 that is parallel with thesecondary shaft 31 is provided along a power transmission path between the counter drivengear 47 and thefinal reduction gear 10 of thevariable belt transmission 9. Theintermediate shaft 50 is supported bybearings gear 53 and afinal drive gear 54 are formed on theintermediate shaft 50. Thecounter drive gear 47 is meshed with the counter drivengear 53. - The
final reduction gear 10 is provided with a hollowdifferential case 55. Thedifferential case 55 is rotatably retained bybearings 56 and 57 and aring gear 58 is provided on an outer periphery of thedifferential case 55. Thefinal drive gear 54 is meshed with thering gear 58. A pinion shaft 59 is mounted inside thedifferential case 55 and two pinion gears 60 are mounted on the pinion shaft 59. Two side gears 61 are meshed with these pinion gears 60. Afront drive shaft 62 is connected independently to each of the two side gears 61 and a wheel (front wheel) 63 is connected to each of thesefront drive shafts 62. - FIG. 3 is a block diagram showing a control system of the vehicle shown in FIG. 2. An
electronic control unit 64 that controls the entire vehicle is made up of a microprocessor comprising mainly a computer processing unit (CPU or MPU), storage devices (RAM and ROM), and an I/O interface. - Signals are input to this
electronic control unit 64 from such devices as anengine speed sensor 65, anaccelerator opening sensor 66, athrottle opening sensor 67, abrake switch 68, ashift position sensor 69 that detects the operating condition of a shiftposition selection unit 69A, aninput speed sensor 70 that detects the input speed of thevariable belt transmission 9, anoutput speed sensor 71 that detects the output speed of thevariable belt transmission 9, anoil temperature sensor 72 that detects the hydraulic fluid temperature of thevariable belt transmission 9 and the torque converter 7, anair conditioner switch 73, and acoolant temperature sensor 74 that detects coolant temperature of the engine 1. - The signal fed from the
shift position sensor 69 is used to determine which is selected, either a drive position [for example, D (drive) position, R (reverse) position, etc.] or a non-drive position [for example, N (neutral) position, P (park) position, etc.]. It is further used to determine which is selected of the two drive positions, either a forward position (for example, D position) or a reverse position (R position). Furthermore, a vehicle speed and a gear ratio of thevariable belt transmission 9 can be calculated by using a signal from theengine speed sensor 65, a signal from theinput speed sensor 70, and a signal from theoutput speed sensor 71 and the like. - The
electronic control unit 64 outputs a signal that controls a fuelinjection control unit 75 of the engine 1, a signal that controls an ignitiontiming control unit 76 of the engine 1, and a signal that controls a hydraulicpressure control unit 77. A construction of the hydraulicpressure control unit 77 will be described. FIG. 4 is an exploded view of some of the component parts of the transaxle 3. Anoil pan 80 is attached to a lower portion of thetransaxle case 5. Avalve body unit 84 formed by integrally assembling anupper valve body 81, aplate 82 and alower valve body 83 are provided between thetransaxle case 5 and theoil pan 80. Thevalve body unit 84 forms a hydraulic circuit. - FIG. 1 is a schematic diagram illustrating a portion of a
hydraulic circuit 85 formed by thevalve body unit 84. FIG. 5 is a sectional view of specific component parts forming thehydraulic circuit 85 shown in FIG. 1. Astrainer 87 is provided in a path extending from theoil pan 80 to asuction opening 86 of theoil pump 20. A construction for mounting thestrainer 87 will be specifically described. Apassage 101 is formed in thelower valve body 83. Thepassage 101 connects to the side of thesuction opening 86. - The
strainer 87 is formed by disposing twodivisions division 87A is disposed above theother division 87B. Thedivision 87A has acylindrical ejection portion 102 that is protruded toward thelower valve body 83. Acylindrical suction portion 102A is protruded toward theoil pan 80. An outer peripheral surface of theejection portion 102 is fitted to an inner peripheral surface of thepassage 101. Due to this fitting force, thestrainer 87 is secured to thelower valve body 83. An O-ring 103 is attached to an outer periphery of theejection portion 102, thus providing a liquid-tight seal between theejection portion 102 and thelower valve body 83. - An
oil transportation path 20A connecting thesuction opening 86 and anejection opening 88 is formed in theoil pump 20. Anoil passage 89 is connected to theejection opening 88. Theoil passage 89 is also connected to an oil chamber (not shown) of ahydraulic actuator 41. - The
hydraulic circuit 85 is also provided with apressure regulator valve 90. Thepressure regulator valve 90 has apressure regulation port 91 and adischarge port 92. Anoil passage 89A branching from an intermediate portion of theoil passage 89 is connected to thepressure regulation port 91. Thepressure regulator valve 90 has a known construction provided with a spool (not shown), a spring (not shown), etc. Thepressure regulator valve 90 is used for controlling the oil pressure at the ejection side of thepressure regulator valve 90. Thepressure regulation port 91 and thehydraulic actuator 41 are disposed in parallel. - A discharge oil passage (in other words, a relief oil passage or a circulating oil passage)93 is formed connecting the
discharge port 92 and thesuction opening 86 of theoil pump 20. Thedischarge oil passage 93 is provided with a cleaningliquid discharge passage 95 that connects to the side of theoil pan 80. - As shown in FIG. 5, the cleaning
liquid discharge passage 95 extends substantially vertically through thelower valve body 83. The cleaningliquid discharge passage 95 is formed above thestrainer 87. Aplug 96 is provided for opening and closing the cleaningliquid discharge passage 95. Theplug 96 has ashaft portion 97 and ahead portion 98. An O-ring 99 is attached to an outer periphery of theshaft portion 97. Theshaft portion 97 of theplug 96 is fitted into the cleaningliquid discharge passage 95 from the side of theoil pan 80. Thestrainer 87 contacts a lower surface of thehead portion 98 of theplug 96 fitted to thelower valve body 83. - The
valve body unit 84 has a solenoid valve (not shown) for controlling the engagement and disengagement of thelockup clutch 19, a solenoid valve (not shown) for controlling the oil pressure supplied and discharged with respect to the oil chambers of thehydraulic actuators hydraulic circuit 85 is further provided with an oil passage (not shown) that connects to thehydraulic actuator 45. - Data used for providing a transmission control of the engine1,
lockup clutch 19, and thevariable belt transmission 9 based on the various signals are stored in theelectronic control unit 64. For example, theelectronic control unit 64 stores data, with which an optimum operating condition of the engine 1 is selected by controlling the gear ratio of thevariable belt transmission 9 based on the accelerator opening, vehicle speed, and other vehicle operating conditions. Theelectronic control unit 64 also stores a lockup clutch control map having the accelerator opening and vehicle speed as parameters. Thelockup clutch 19 is controlled through each state of engagement, disengagement, and slip based on this lockup clutch control map. Theelectronic control unit 64 outputs control signals to the fuelinjection control unit 75, the ignitiontiming control unit 76, and the hydraulicpressure control unit 77 based on the various signals input to theelectronic control unit 64 and the data stored in theelectronic control unit 64. - The corresponding relationships between the construction of this embodiment and the construction of the invention will now be described. The
oil passage 89 corresponds to an oil passage in the invention. Thepressure regulator valve 90 corresponds to a pressure regulator device in the invention. Theplug 96 corresponds to a lid member and a sealing device in the invention. Theoil passage discharge oil passage 93 correspond to a circulating oil passage in the invention. Thestrainer 87 corresponds to a filtering device in the invention. - An example of control content of a vehicle of this configuration will hereinafter be described. The forward-reverse selection mechanism8 is controlled based on operation of the shift
position selection unit 69A. When a forward position is selected, the forward clutch CR is engaged and the reverse brake BR is released, which results in the input shaft 11 being directly connected to theprimary shaft 30. When the torque (or power) of the engine 1 is transmitted via the torque converter 7 to the input shaft 11 in this state, the input shaft 11, carrier 29, and theprimary shaft 30 turn integrally. The torque of theprimary shaft 30 is transmitted via theprimary pulley 36, thebelt 46, and thesecondary pulley 37 to thesecondary shaft 31. - The torque transmitted to the
secondary shaft 31 is transmitted to theintermediate shaft 50 by way of thecounter drive gear 47 and the counter drivengear 53. The torque transmitted to theintermediate shaft 50 is transmitted to thedifferential case 55 by way of thefinal drive gear 54 and thering gear 58. When thedifferential case 55 turns, its torque is transmitted to thedrive shaft 62 by way of thepinion gear 60 and the side gear 61, and then transmitted to thewheel 63. - When the reverse position is selected, on the other hand, the forward clutch CR is disengaged and the reverse brake BR is engaged, thus locking the ring gear26. Then, as the input shaft 11 turns, the pinion gears 27 and 28 rotate while they rotate on their own axes. The carrier then rotates in a direction opposite the direction of rotation of the input shaft 11. As a result, the
primary shaft 30,secondary shaft 31,intermediate shaft 50, and so forth rotate in a direction opposite that of when a forward position is selected, allowing the vehicle to reverse. - The gear ratio of the
variable belt transmission 9 is controlled so that the operating conditions of the engine 1 may be optimized based on vehicle acceleration requirements evaluated with the vehicle speed, accelerator opening, and other conditions (namely, drive power requirements), data stored in the electronic control unit 64 (for example, an optimum fuel consumption curve having the engine speed and throttle opening as parameters), and other factors. To be more specific, the width of thegroove 40 in theprimary pulley 36 is varied by controlling the hydraulic pressure of the hydraulic chamber of thehydraulic actuator 41. As a result, the winding radius of thebelt 4 of theprimary pulley 36 is changed, which means that the ratio of the input speed to the output speed of thevariable belt transmission 9, namely the gear ratio, is controlled steplessly (continuously). - Furthermore, by controlling the oil pressure in the oil chamber of the
hydraulic actuator 45, the width of the groove 44 of thesecondary pulley 37 is changed. That is, the clamping pressure (i.e., clamping force) of thesecondary pulley 37 on thebelt 31 in the direction of the axis thereof is controlled. Based on the clamping pressure, the tension of thebelt 31 is controlled so that the contact surface pressure between theprimary pulley 36 and thebelt 31 and between thesecondary pulley 37 and thebelt 31 is controlled. The oil pressure in the oil chamber of thehydraulic actuator 45 is controlled based on the torque input to thevariable belt transmission 9, the speed ratio of thevariable belt transmission 9, etc. The torque input to thevariable belt transmission 9 is determined based on the engine revolution speed, the degree of throttle opening, the torque ratio of the torque converter 7, etc. - Next described will be a flushing operation of cleaning the
hydraulic circuit 85 of thevalve body unit 84. During a process preceding the mounting of thevalve body unit 84 between thetransaxle case 5 and the oil pan 80 (i.e., a process before shipment of the transaxle 3 from a factory), a flushing operation of cleaning the interior of thehydraulic circuit 85 is performed to remove foreign substances, for example, waste, dust, or the like, which may be present within thehydraulic circuit 85. - To perform the flushing operation, an
oil pump 100, separate from theoil pump 20, is provided between thestrainer 87 and theoil pan 80 as shown in FIG. 6, and theplug 96 is removed to open the cleaningliquid discharge passage 95. Then, using theoil pump 100, a cleaning liquid (which may be an automatic transmission fluid (ATF) that is the operating fluid of the transaxle 3) is supplied from theoil pan 80 into thehydraulic circuit 85. The cleaning liquid is pumped into theoil passage 89, and the pressure in theoil passage 89 rises to a predetermined pressure. Then, via thepressure regulator valve 90, thepressure regulation port 91 and thedischarge port 92 are connected in communication, so that the cleaning liquid is discharged into thedischarge oil passage 93 via thedischarge port 92. - Since the cleaning
liquid discharge passage 95 is opened as mentioned above, the cleaning liquid is discharged from thedischarge oil passage 93 into theoil pan 80 via the cleaningliquid discharge passage 95. Therefore, the cleaning liquid used to remove foreign substances from thehydraulic circuit 85 will not return to thehydraulic circuit 85. After the cleaning of thehydraulic circuit 85 ends, the cleaningliquid discharge passage 95 is liquid-tightly closed by theplug 96 as shown in FIGS. 1 and 5, and theoil pump 100 is removed. - Alternatively, the
oil pump 20 and thepressure regulator valve 90 can also be cleaned by driving theoil pump 20 and driving theoil pump 100 after mounting thevalve body unit 84 and thestrainer 87 below thetransaxle case 5. - After the transaxle3 is assembled, the ejection pressure of the
oil pump 20 is supplied to theoil passage 89. The oil pressure in theoil passage 89 rises to a predetermined pressure. Then, via thepressure regulator valve 90, thepressure regulation port 91 and thedischarge port 92 are connected in communication, so that oil is discharged from thepressure regulation port 91 into thedischarge oil passage 93 via thedischarge port 92. Since the cleaningliquid discharge passage 95 has been closed, the oil pressure in thedischarge oil passage 93 is transmitted to thesuction opening 86 of theoil pump 20. Thus, a circulating operation occurs in which the oil pressure ejected from the ejection opening 88 of theoil pump 20 is supplied back to thesuction opening 86 of theoil pump 20 via thepressure regulator valve 90 and thedischarge oil passage 93. That is, it can be said that thedischarge oil passage 93 forms a super charge circuit. - FIG. 7 illustrates another embodiment of the hydraulic circuit cleaning apparatus and cleaning method, showing a portion of a
hydraulic circuit 85. In thehydraulic circuit 85 shown in FIG. 7, constructions substantially the same as those of the embodiment shown in FIGS. 1 to 6 are represented by reference characters which are the same as those used in FIGS. 1 to 6. Such constructions will not be described again. - In FIG. 7, the
hydraulic circuit 85 has twopressure regulator valves pressure regulator valve 104 has apressure regulation port 105 and adischarge port 106. Thepressure regulator valve 108 has apressure regulation port 109 and adischarge port 110. Anoil passage 89A branching from anoil passage 89 is connected to thepressure regulation port 105. Thedischarge port 106 and thepressure regulation port 109 are connected by anoil passage 107. Thedischarge port 110 is connected to the side of asuction opening 86 of anoil pump 20 via a discharge oil passage (i.e., a circulating oil passage a relief oil passage) 93. Thus, thepressure regulator valve 104 and thepressure regulator valve 108 are connected in series. Anoil passage 111 connecting thehydraulic actuator 41 and theoil passage 107 is provided. In thehydraulic circuit 85 shown in FIG. 7, thepressure regulator valves oil passages - When a cleaning liquid is injected via the
suction opening 86 of theoil pump 20 of thehydraulic circuit 85 of FIG. 7 with theplug 96 having been removed, the cleaning liquid reaches thepressure regulator valve 104 via theoil passages discharge port 106 of thepressure regulator valve 104, and reaches thepressure regulator valve 108 via theoil passage 107, and is discharged from thedischarge port 110, and reaches thedischarge oil passage 93. The cleaning liquid is then discharged from thedischarge oil passage 93 into theoil pan 80 via the cleaningliquid discharge passage 95. Therefore, the cleaning liquid used to clean the interior of thehydraulic circuit 85 will not circulate in thehydraulic circuit 85. Thus, thehydraulic circuit 85 of this embodiment achieves substantially the same advantages as those achieved by thehydraulic circuit 85 shown in FIG. 1. Furthermore, after theplug 96 is attached to thehydraulic circuit 85 shown in FIG. 7, thehydraulic circuit 85 achieves substantially the same advantages as those achieved by thehydraulic circuit 85 shown in FIG. 1. - According to the embodiments shown in FIGS.1 to 7, the flushing operation can be performed after the transaxle 3 is manufactured. Furthermore, after the flushing operation, the suction force of the
oil pump 20 is supplemented with the oil pressure in thedischarge oil passage 93, so that the oil suction function of theoil pump 20 improves. That is, it becomes possible to perform the flushing operation in a process after manufacture of the transaxle 3, without degrading the effect of re-supplying oil pressure to thesuction opening 86 of the oil pump 20 (i.e., the super charge effect). - Furthermore, according to the embodiments, when the
strainer 87 is secured to thelower valve body 83 after the cleaningliquid discharge passage 95 is closed by theplug 96, thestrainer 87 contacts thehead portion 98 of theplug 96 as shown in FIG. 5. That is, thestrainer 87 performs both the function of cleaning oil supplied from the side of theoil pan 80 to the side of thestrainer 87 and the function of preventing theplug 96 from falling from the lower valve body 83 (generally termed fall-apart preventing function). Therefore, it is unnecessary to separately provide a component part for preventing theplug 96 from falling. Hence, the number of component parts required for the cleaning apparatus is reduced, thereby allowing size and weight reductions of the apparatus and curbing increases in the production cost of the apparatus. - The foregoing embodiments are also applicable to automatic transmissions other than the continuously variable belt transmission, for example, an automatic transmission that has a planetary gear mechanism and friction engagement devices, such as clutches, brakes and the like, which are engaged and disengaged to change the torque transmission path. That is, each embodiment can be used as a hydraulic circuit cleaning apparatus for a hydraulic control apparatus that controls the engagement and disengagement of the friction engagement devices and the engagement pressure for the devices.
- Furthermore, each embodiment can also be used as a hydraulic circuit cleaning apparatus for a hydraulic control apparatus of a toroidal type continuously variable transmission. The toroidal type continuously variable transmission refers to a continuously variable transmission having a plurality of cone discs each of which has a power transmission surface of an arcuate shape corresponding to the shape of an outer peripheral surface of a doughnut, and at least one power roller that contacts the power transmission surfaces of the cone discs via a lubricant (traction oil). By controlling the operation of the power roller through the use of the hydraulic control apparatus, the radius of the contact between the power roller and the power transmission surfaces is controlled to control the transmission speed ratio. The cleaning apparatus of each of the foregoing embodiments is applicable to the hydraulic circuit of the hydraulic control apparatus for controlling the power roller.
- The foregoing embodiments are also applicable to vehicles that employ drive power sources other then internal combustion engines, for example, electric motors. The embodiments are also applicable to vehicles that incorporate combinations of engines and electric motors as drive power sources.
Claims (10)
Applications Claiming Priority (2)
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JP2000-150404 | 2000-05-22 | ||
JP2000150404A JP2001327939A (en) | 2000-05-22 | 2000-05-22 | Cleaning device for hydraulic circuit and cleaning method |
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US20010045221A1 true US20010045221A1 (en) | 2001-11-29 |
US6449948B2 US6449948B2 (en) | 2002-09-17 |
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US09/861,515 Expired - Fee Related US6449948B2 (en) | 2000-05-22 | 2001-05-22 | Hydraulic circuit cleaning apparatus and method |
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US (1) | US6449948B2 (en) |
EP (1) | EP1158212A3 (en) |
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Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070062562A1 (en) * | 2005-09-16 | 2007-03-22 | Dwight Leaphart | Method of cleaning oil strainer |
JP2009521886A (en) * | 2005-12-28 | 2009-06-04 | エレクトロビット・システム・テスト・オサケユキテュア | Method, apparatus, analyzer and computer program for searching propagation path |
US20140257650A1 (en) * | 2007-02-01 | 2014-09-11 | Fallbrook Intellectual Property Company Llc | Systems and methods for control of transmission and/or prime mover |
CN105935679A (en) * | 2016-05-27 | 2016-09-14 | 上海二十冶建设有限公司 | Multifunctional oil flushing device and application method thereof |
CN110168253A (en) * | 2017-03-14 | 2019-08-23 | 株式会社小松制作所 | Hydraulic circuit |
CN112160803A (en) * | 2020-10-20 | 2021-01-01 | 中广核核电运营有限公司 | Method for flushing regulating oil system of steam turbine of nuclear power station |
US11644094B2 (en) * | 2020-01-23 | 2023-05-09 | Kawasaki Motors, Ltd. | Power unit |
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FR2370317A1 (en) * | 1976-11-03 | 1978-06-02 | Poclain Hydraulics Sa | Pressure fluid source with adjustable throughput - has pump with fixed stroke and two position distributor in fluid return conduit |
JPS5747002A (en) * | 1980-09-05 | 1982-03-17 | Nissei Plastics Ind Co | Flow supplying method by variable discharge pump |
US4694649A (en) * | 1983-02-04 | 1987-09-22 | Howeth David F | Pressure limiting acceleration control system and valve for hydraulic motors |
DE3516710A1 (en) * | 1985-05-09 | 1986-11-13 | Robert Bosch Gmbh, 7000 Stuttgart | CONTAINER ARRANGEMENT FOR VEHICLES WITH A COMMON OIL BUDGET |
US4731999A (en) * | 1987-04-24 | 1988-03-22 | Vickers, Incorporated | Power transmission |
JPH06182122A (en) * | 1992-12-16 | 1994-07-05 | Mitsubishi Motors Corp | Oil pressure circuit |
JP3196415B2 (en) * | 1993-03-29 | 2001-08-06 | 豊田工機株式会社 | Flow control device for power steering device |
US5337708A (en) * | 1993-06-15 | 1994-08-16 | Chen We Yu | Apparatus and method for automatic transmission system fluid exchange and internal system flushing |
US5600953A (en) * | 1994-09-28 | 1997-02-11 | Aisin Seiki Kabushiki Kaisha | Compressed air control apparatus |
US5630316A (en) * | 1994-11-16 | 1997-05-20 | Sumitomo Heavy Industries, Ltd. | Hydraulic driving apparatus using a bladder-type accumulator with an improved safety |
JPH1037734A (en) | 1996-07-24 | 1998-02-10 | Toshiba Corp | Lubricating oil supplying device and washing method for oil cooler |
JP2000045728A (en) * | 1998-08-03 | 2000-02-15 | Unisia Jecs Corp | Hydraulic circuit of internal combustion engine |
-
2000
- 2000-05-22 JP JP2000150404A patent/JP2001327939A/en active Pending
-
2001
- 2001-05-21 EP EP01112414A patent/EP1158212A3/en not_active Withdrawn
- 2001-05-22 US US09/861,515 patent/US6449948B2/en not_active Expired - Fee Related
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20070062562A1 (en) * | 2005-09-16 | 2007-03-22 | Dwight Leaphart | Method of cleaning oil strainer |
US7422021B2 (en) | 2005-09-16 | 2008-09-09 | Dwight Leaphart | Method of cleaning oil strainer |
JP2009521886A (en) * | 2005-12-28 | 2009-06-04 | エレクトロビット・システム・テスト・オサケユキテュア | Method, apparatus, analyzer and computer program for searching propagation path |
US20140257650A1 (en) * | 2007-02-01 | 2014-09-11 | Fallbrook Intellectual Property Company Llc | Systems and methods for control of transmission and/or prime mover |
US9328807B2 (en) * | 2007-02-01 | 2016-05-03 | Fallbrook Intellectual Property Company Llc | Systems and methods for control of transmission and/or prime mover |
US9676391B2 (en) | 2007-02-01 | 2017-06-13 | Fallbrook Intellectual Property Company Llc | Systems and methods for control of transmission and/or prime mover |
US9878719B2 (en) | 2007-02-01 | 2018-01-30 | Fallbrook Intellectual Property Company Llc | Systems and methods for control of transmission and/or prime mover |
US10703372B2 (en) | 2007-02-01 | 2020-07-07 | Fallbrook Intellectual Property Company Llc | Systems and methods for control of transmission and/or prime mover |
CN105935679A (en) * | 2016-05-27 | 2016-09-14 | 上海二十冶建设有限公司 | Multifunctional oil flushing device and application method thereof |
CN110168253A (en) * | 2017-03-14 | 2019-08-23 | 株式会社小松制作所 | Hydraulic circuit |
US11644094B2 (en) * | 2020-01-23 | 2023-05-09 | Kawasaki Motors, Ltd. | Power unit |
CN112160803A (en) * | 2020-10-20 | 2021-01-01 | 中广核核电运营有限公司 | Method for flushing regulating oil system of steam turbine of nuclear power station |
Also Published As
Publication number | Publication date |
---|---|
EP1158212A3 (en) | 2003-09-10 |
US6449948B2 (en) | 2002-09-17 |
EP1158212A2 (en) | 2001-11-28 |
JP2001327939A (en) | 2001-11-27 |
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