JP2019148287A - Fluid supply device and pressing apparatus - Google Patents

Abstract

A fluid supply device includes a pump driven by an electric motor, a solenoid valve whose valve opening changes according to a supplied control current, and a control device that supplies current to the electric motor and the solenoid valve. Provided are a fluid supply device and a pressing device that can detect an abnormality of a solenoid valve with high accuracy when an abnormality occurs in the pressing device. An electric motor (80), a pump (81) driven by the electric motor (80), an electromagnetic valve (82) whose valve opening changes according to a supplied control current, and a drive current supplied to the electric motor (80) In the fluid supply device 100 including the control device 9 that supplies the control current to the valve 82, the control device 9 determines that the operation state of the electric motor 80 when the control current is changed during the operation of the electric motor 80 exceeds the threshold value. When it does not change, it is determined that an abnormality has occurred in the electromagnetic valve 82. [Selection diagram] FIG.

Description

  The present invention relates to a fluid supply device including a pump driven by an electric motor, and a pressing device that presses an object to be pressed by the pressure of a fluid supplied from the fluid supply device.

  2. Description of the Related Art Conventionally, a device that drives a pump by an electric motor and adjusts and outputs the pressure of hydraulic oil discharged from the pump by an electromagnetic valve is used to operate, for example, a clutch that transmits a driving force of a vehicle ( For example, see Patent Document 1).

  The hydraulic control device described in Patent Document 1 is a hydraulic oil for pressing a clutch that transmits driving force in a four-wheel drive state to a transfer of a four-wheel drive vehicle that can switch between a two-wheel drive state and a four-wheel drive state. A pump driven by an electric motor, a switching valve that switches a flow path of hydraulic oil discharged from the pump between a two-wheel driving state and a four-wheel driving state, and a control pressure to the switching valve An electromagnetic on-off valve, a pressure detection means for detecting the pressure of hydraulic oil between the switching valve and the transfer, and whether the hydraulic oil at a predetermined pressure is output from the switching valve based on a detection value of the pressure detection means And a warning means for notifying that an abnormality of the switching valve has occurred when it is determined by the hydraulic switch that hydraulic oil having a predetermined pressure is not output.

Japanese Patent Laid-Open No. 7-186752

  In the hydraulic control device described in Patent Document 1, it is necessary to provide a hydraulic switch in order to detect an abnormality of the switching valve, which causes a cost increase. Also, when judging whether there is an abnormality only by turning on or off the hydraulic switch, for example, when an abnormality occurs such that the valve body of the switching valve sticks at an intermediate position of the movable range, the abnormality is correctly detected. It may not be possible.

  Therefore, the present invention provides a fluid including a pump driven by an electric motor, an electromagnetic valve whose valve opening changes in accordance with a supplied control current, and a control device that supplies current to the electric motor and the electromagnetic valve. An object of the present invention is to provide a fluid supply device and a pressing device capable of detecting the abnormality with high accuracy when an abnormality of the electromagnetic valve occurs in the supply device and the pressing device.

  In order to achieve the above object, the present invention provides an electric motor that operates with a supplied drive current, a pump that is driven by the electric motor, and an electromagnetic valve that changes in valve opening according to the supplied control current. And a controller for supplying the drive current to the electric motor and supplying the control current to the electromagnetic valve, and supplying the fluid discharged from the pump to the supply target with the valve opening adjusted The fluid supply device, wherein the control device generates an abnormality in the electromagnetic valve when an operating state of the electric motor does not change exceeding a threshold when the control current is changed during operation of the electric motor. Provided is a fluid supply device that executes an abnormality determination control for determining that an operation is being performed.

  According to the fluid supply device and the pressing device according to the present invention, when an abnormality occurs in the electromagnetic valve, the abnormality can be detected with high accuracy.

It is a block diagram which shows typically the structural example of the four-wheel drive vehicle by which the driving force distribution apparatus which concerns on embodiment of this invention is mounted. It is sectional drawing which shows the structural example of a driving force distribution apparatus. FIG. 3 is an enlarged view of FIG. 2. It is a block diagram which shows the structural example of a press apparatus typically. It is sectional drawing which shows the structural example of a solenoid valve. It is a flowchart which shows an example of the procedure of the abnormality determination control which a control part performs. (A) And (b) is a graph which shows the operating state of an electric motor, and the change of control current when abnormality has not generate | occur | produced in the solenoid valve at the time of execution of abnormality determination control. (A) And (b) is a graph which shows the operating state of an electric motor, and the change of control current when abnormality has generate | occur | produced in the solenoid valve at the time of execution of abnormality determination control. It is a block diagram which shows the structure of the hydraulic unit which concerns on a modification.

[Embodiment]
Embodiments of the present invention will be described with reference to FIGS. In addition, although embodiment described below is shown as a suitable specific example in implementing this invention, although there are some parts which have illustrated various technical matters that are technically preferable. The technical scope of the present invention is not limited to this specific embodiment.

  FIG. 1 is a configuration diagram schematically showing a configuration example of a four-wheel drive vehicle equipped with a driving force distribution device according to an embodiment of the present invention.

  The four-wheel drive vehicle 1 includes an engine 102 as a drive source for generating a driving force for traveling, a transmission 103, front wheels 104L and 104R as a pair of left and right main drive wheels, and a rear wheel 105L as a pair of left and right auxiliary drive wheels, 105R, a driving force transmission system 101 capable of transmitting the driving force of the engine 102 to the front wheels 104L, 104R and the rear wheels 105L, 105R, and a pressing device 10 for switching the driving force transmission state in the driving force transmission system 101. ing. The four-wheel drive vehicle 1 includes a four-wheel drive state in which the driving force of the engine 102 is transmitted to the front wheels 104L and 104R and the rear wheels 105L and 105R, and a two-wheel drive in which the driving force of the engine 102 is transmitted only to the front wheels 104L and 104R. The state can be switched. In the present embodiment, “L” and “R” in each symbol are used to mean the left side and the right side with respect to the forward direction of the vehicle.

  The driving force transmission system 101 includes a front differential 11, a meshing clutch 12 capable of interrupting transmission of driving force, a propeller shaft 108, a driving force distribution device 13, front wheel side drive shafts 106L and 106R, and a rear wheel side. Drive shafts 107L and 107R. The driving force of the engine 102 is always transmitted to the front wheels 104L and 104R. The driving force of the engine 102 is transmitted to the rear wheels 105L and 105R via the meshing clutch 12, the propeller shaft 108, and the driving force distribution device 13. The driving force distribution device 13 can distribute the driving force of the engine 102 to the left and right rear wheels 105L and 105R while allowing a differential.

  The front differential 11 supports a pair of side gears 111 respectively connected to a pair of front-wheel drive shafts 106L and 106R, a pair of pinion gears 112 that mesh with the pair of side gears 111 with their gear axes orthogonal to each other, and a pair of pinion gears 112. A pinion gear shaft 113 and a pair of side gears 111, a pair of pinion gears 112, and a front differential case 114 that accommodates the pinion gear shaft 113 are included. The driving force of the engine 102 changed by the transmission 103 is transmitted to the front differential case 114.

  The meshing clutch 12 includes a first rotating member 121 that rotates integrally with the front differential case 114, a second rotating member 122 that is arranged in the axial direction with the first rotating member 121, a first rotating member 121, and a second rotating member. And a sleeve 123 that can be connected to the member 122 so as not to be relatively rotatable. The sleeve 123 moves in the axial direction between a connection position that meshes with the first rotation member 121 and the second rotation member 122 and a non-connection position that meshes only with the second rotation member 122 by an actuator (not shown). When the sleeve 123 is in the connection position, the first rotation member 121 and the second rotation member 122 are connected so as not to be relatively rotatable, and when the sleeve 123 is in the non-connection position, the first rotation member 121 and the second rotation member 122 are connected. And can rotate relative to each other.

  The propeller shaft 108 receives the torque of the engine 102 from the front differential case 114 via the meshing clutch 12 and transmits the torque to the driving force distribution device 13 side. A pinion gear 108 a is provided at the front wheel side end of the propeller shaft 108, and the pinion gear 108 a meshes with a ring gear 108 b that is connected to the second rotating member 122 of the meshing clutch 12 so as not to be relatively rotatable. The driving force distribution device 13 distributes the driving force input from the propeller shaft 108 while allowing the differential to the drive shafts 107L and 107R on the rear wheel side. The drive shaft 107L is connected to the left rear wheel 105L, and the drive shaft 107R is connected to the right rear wheel 105R.

(Configuration of driving force distribution device)
FIG. 2 is a cross-sectional view illustrating a configuration example of the driving force distribution device 13. FIG. 3 is an enlarged view of FIG. In FIG. 2, the entire driving force distribution device 13 is shown together with part of the drive shafts 107L, 107R on the rear wheel side.

  The driving force distribution device 13 includes a device case 2 supported by a vehicle body, a connecting member 31 to which the propeller shaft 108 is connected, a pinion gear shaft 32 that rotates integrally with the connecting member 31, and driving the engine 102 from the pinion gear shaft 32. A differential case 40 that rotates by receiving force, a differential gear mechanism 4 that outputs a driving force input to the differential case 40 while allowing a differential to be output from a pair of side gears 43, and one side gear 43 of the differential gear mechanism 4. A driving force transmission device 5 having a friction clutch 53 that transmits a driving force to and from the drive shaft 107L, and a shaft-shaped intermediate shaft 50 disposed between the differential gear mechanism 4 and the driving force transmission device 5 are provided. I have. The connecting member 31 and the pinion gear shaft 32 are coupled by a bolt 301 and a washer 302. The pinion gear shaft 32 includes a shaft portion 321 and a gear portion 322, and the shaft portion 321 is rotatably supported by a pair of tapered roller bearings 61 and 62.

  The differential gear mechanism 4 includes a pinion shaft 41 supported by the differential case 40, a pair of pinion gears 42 supported by the pinion shaft 41, and a pair of side gears 43 that mesh with the pair of pinion gears 42 with their gear axes orthogonal to each other. have. The differential case 40 is rotatably supported by the device case 2 by tapered roller bearings 63 and 64. The intermediate shaft 50 is coupled to one side gear 43 of the pair of side gears 43 so as not to be relatively rotatable. The driving force transmission device 5 transmits the driving force input from the intermediate shaft 50 to the drive shaft 107L in an intermittent and adjustable manner.

  When the driving force transmitted from one side gear 43 to the drive shaft 107L via the intermediate shaft 50 and the driving force transmission device 5 is adjusted when the four-wheel drive vehicle 1 goes straight, the differential function of the differential gear mechanism 4 is adjusted. Thus, a driving force equivalent to the driving force transmitted to the drive shaft 107L is also transmitted to the drive shaft 107R. The drive shaft 107 </ b> R is connected to the other side gear 43, which is opposite to the intermediate shaft 50, of the pair of side gears 43 by spline fitting so that relative rotation is impossible. The drive shaft 107L is connected to a connecting portion 521 of a second rotating member 52, which will be described later, by spline fitting so as not to be relatively rotatable.

(Configuration of driving force transmission device)
The driving force transmission device 5 includes a first rotating member 51 that rotates integrally with the intermediate shaft 50, a second rotating member 52 that rotates integrally with the drive shaft 107L, and the first rotating member 51 and the second rotating member 52. It has a friction clutch 53 disposed between them, and a pressure plate 54 and a thrust roller bearing 55 disposed between the piston 7 serving as a pressing force output member in the pressing device 10 and the friction clutch 53. The driving force transmission device 5 outputs the driving force input to the first rotating member 51 from the second rotating member 52 to the drive shaft 107L. The first rotating member 51 corresponds to the input rotating member of the present invention, and the second rotating member 52 corresponds to the output rotating member of the present invention.

  As shown in FIG. 3, the friction clutch 53 includes a plurality of inner clutch plates 531 that rotate together with the first rotating member 51 and a plurality of outer clutch plates 532 that rotate together with the second rotating member 52. The frictional sliding between the inner clutch plate 531 and the outer clutch plate 532 is lubricated by an unillustrated lubricating oil. The plurality of inner clutch plates 531 and the plurality of outer clutch plates 532 are alternately arranged along the axial direction.

  The friction clutch 53 receives the pressing force of the piston 7 via the pressure plate 54 and the thrust roller bearing 55, and the friction force between the inner clutch plate 531 and the outer clutch plate 532 is generated by the first rotating member 51 and the second rotating member 51. A driving force is transmitted to and from the rotating member 52. The piston 7 presses the friction clutch 53 by the axial movement along the rotation axis O of the first rotating member 51 and the second rotating member 52.

  When the hydraulic oil is not supplied to the cylinder 220, a gap is formed between the inner clutch plate 531 and the outer clutch plate 532, and a torque higher than the drag torque by the lubricating oil is transmitted from the first rotating member 51 to the second rotating member. 52 is not transmitted. When hydraulic oil is supplied to the cylinder 220 from this state, the piston 7 moves forward to close the gap between the inner clutch plate 531 and the outer clutch plate 532, and when the pressure in the cylinder 220 further increases, the inner clutch The plate 531 and the outer clutch plate 532 are in frictional contact, and the driving force is transmitted from the first rotating member 51 to the second rotating member 52. The pressing force applied to the friction clutch 53 during the forward movement of the piston 7 is small until the gap between the two clutch plates 531 and 532 is clogged, and increases after the gap between the two clutch plates 531 and 532 is clogged.

  The first rotating member 51 includes a cylindrical cylindrical portion 511 in which a spline engaging portion 511a including a plurality of spline protrusions extending in the axial direction is formed on the outer peripheral surface, a smaller diameter than the cylindrical portion 511, and an intermediate shaft 50 Are integrally provided with a bottomed cylindrical connecting portion 512 that is connected by spline fitting, and a connecting portion 513 that connects the cylindrical portion 511 and the connecting portion 512. A seal member 690 supported by the device case 2 is in sliding contact with the outer peripheral surface of the connecting portion 512. The seal member 690 divides the accommodation space of the driving force transmission device 5 and the accommodation space of the differential gear mechanism 4.

  The pressure plate 54 is formed with an insertion hole 540 through which a protrusion 511 b formed at the end of the cylindrical portion 511 of the first rotating member 51 is inserted, and is not rotatable relative to the first rotating member 51 and moves in the axial direction. Is possible. The pressure plate 54 includes a pressing portion 541 that is disposed on the outer peripheral side of the cylindrical portion 511 of the first rotating member 51 and presses the friction clutch 53, and an inner wall portion 542 that is disposed inside the cylindrical portion 511. Yes. The insertion hole 540 is formed between the pressing part 541 and the inner wall part 542. Between the inner wall part 542 of the pressure plate 54 and the connection part 513 of the first rotating member 51, a plurality of coil springs 57 are arranged in a state compressed in the axial direction. 2 and 3, one of the coil springs 57 is illustrated. The plurality of coil springs 57 urge the pressure plate 54 toward the piston 7 side.

  The second rotating member 52 is juxtaposed with the first rotating member 51 in the axial direction. As shown in FIG. 3, the second rotating member 52 includes a connecting portion 521 to which the drive shaft 107L is connected, a boss portion 522 that protrudes in the axial direction from an end portion of the connecting portion 521 on the first rotating member 51 side, An annular wall portion 523 projecting outward from the connecting portion 521 and a cylindrical cylindrical portion 524 extending in the axial direction from the outer peripheral end portion of the wall portion 523 are integrally provided.

  The friction clutch 53 is disposed between the cylindrical portion 511 of the first rotating member 51 and the cylindrical portion 524 of the second rotating member 52. The inner clutch plate 531 is formed with a plurality of protrusions 531 a that are engaged with the spline engaging portions 511 a of the cylindrical portion 511 of the first rotating member 51 at the inner peripheral end thereof. Thereby, the inner clutch plate 531 is connected to the first rotating member 51 so as to be movable in the axial direction but not relatively rotatable. The outer clutch plate 532 has a plurality of protrusions 532a that engage with spline engaging portions 524a formed on the inner peripheral surface of the cylindrical portion 524 of the second rotating member 52 at the outer peripheral end portion. Yes. Accordingly, the outer clutch plate 532 is connected to the second rotating member 52 so as to be movable in the axial direction and not to be relatively rotatable.

  The first rotating member 51 is supported by a ball bearing 65 attached to the device case 2. The second rotating member 52 is supported by a ball bearing 66 disposed between the connecting portion 521 and the inner surface of the device case 2. A ball bearing 67 is disposed between the outer peripheral surface of the boss portion 522 of the second rotating member 52 and the first rotating member 51. A thrust roller bearing 68 is disposed between the wall portion 523 of the second rotating member 52 and the inner surface of the first case member 21.

  The device case 2 includes a first case member 21 that houses the driving force transmission device 5, a second case member 22 in which the cylinder 220 is formed, and a third case member 23 that houses the differential gear mechanism 4 and the differential case 40. And have. The first case member 21 and the second case member 22, and the second case member 22 and the third case member 23 are coupled by, for example, bolt fastening. 2 and 3, a plurality of bolts 201 that join the first case member 21 and the second case member 22 are illustrated.

  In the first case member 21, a seal member 691 is fitted on the inner surface of the insertion hole through which the second rotating member 52 is inserted. In the third case member 23, a seal member 692 is fitted into the inner surface of the insertion hole through which the drive shaft 107R is inserted, and a seal member 693 is fitted into the inner surface of the insertion hole through which the coupling member 31 and the pinion gear shaft 32 are inserted. ing.

  The second case member 22 is provided with an annular cylinder 220 that is supplied with hydraulic oil that applies hydraulic pressure to the piston 7 and moves the piston 7 toward the friction clutch 53, and a hydraulic oil supply hole that supplies hydraulic oil to the cylinder 220. 221 is provided. The cylinder 220 has an annular shape formed around the rotation axis O. The hydraulic oil is one aspect of the fluid of the present invention.

  The hydraulic oil is supplied to the cylinder 220 through the hydraulic oil supply hole 221. The piston 7 can move back and forth in the direction of the rotation axis O in a state where a part of the piston 7 is disposed in the cylinder 220, and presses the friction clutch 53 by the hydraulic pressure of the hydraulic oil supplied to the cylinder 220, thereby The plate 531 and the outer clutch plate 532 are brought into friction contact. As a result, the driving force is transmitted from the propeller shaft 108 to the rear wheels 105L and 105R. Further, when the pressure of the hydraulic oil in the cylinder 220 decreases, the piston 7 moves to the back side of the cylinder 220 by the urging force of the coil spring 57 received via the pressure plate 54 and is separated from the friction clutch 53. Circumferential grooves are formed on the inner peripheral surface and the outer peripheral surface of the piston 7, and O-rings 71 and 72 are held in these circumferential grooves.

(Configuration of the pressing device 10)
As shown in FIG. 1, the pressing device 10 includes a fluid supply device 100 that supplies hydraulic oil to a cylinder 220 that is a supply target of hydraulic oil, and a piston 7 that moves forward by the pressure of the cylinder 220. ing. The piston 7 presses the friction clutch 53 that is a pressing object by the hydraulic pressure in the cylinder 220. The fluid supply device 100 includes a hydraulic unit 8 and a control device 9 that controls the hydraulic unit 8.

  FIG. 4 is a configuration diagram schematically illustrating a configuration example of the pressing device 10. The hydraulic unit 8 has an electric motor 80 that is operated by a drive current supplied from the control device 9, a pump 81 that is driven by the electric motor 80, and a valve opening that changes according to the control current supplied from the control device 9. And an electromagnetic valve 82. The electric motor 80 and the pump 81 are connected by a connecting shaft 811. A reduction gear that reduces the rotation of the electric motor 80 at a predetermined reduction ratio may be provided between the electric motor 80 and the pump 81. Alternatively, the electric motor 80 and the pump 81 may be unitized, and the electric pump may be configured integrally.

  The fluid supply device 100 supplies the fluid discharged from the pump 81 to the cylinder 220 by adjusting the valve opening degree of the electromagnetic valve 82. The electric motor 80 is, for example, a three-phase brushless motor, and its rotation speed is detected by a rotation speed sensor 801. Further, the current value of the drive current supplied to the electric motor 80 is detected by the current sensor 802. Detection signals from the rotation speed sensor 801 and the current sensor 802 are sent to the control device 9.

  The pump 81 is known per se, and discharges hydraulic fluid pumped from the reservoir 810 with a discharge amount corresponding to the rotation speed of the electric motor 80 to generate hydraulic pressure to be supplied to the electromagnetic valve 82. Specifically, an external gear pump, an internal gear pump, a vane pump, or the like can be used as the pump 81. Part of the hydraulic oil discharged from the pump 81 returns to the reservoir 810 through the oil passage 812. An orifice (throttle valve) 813 is provided in the oil passage 812.

  The electromagnetic valve 82 is disposed between the pump 81 and the cylinder 220 and adjusts the pressure of hydraulic oil supplied from the pump 81 to the cylinder 220. The pressure of the hydraulic oil output to the cylinder 220 changes according to the control current supplied from the control device 9 to the electromagnetic valve 82. The electromagnetic valve 82 discharges a part of the hydraulic oil discharged from the pump 81, reduces the pressure of the hydraulic oil, and outputs it to the cylinder 220. The control device 9 controls the electric motor 80 so that the discharge pressure of the pump 81 is higher than the hydraulic pressure of the hydraulic oil to be applied to the piston 7.

  FIG. 5 is a cross-sectional view illustrating a configuration example of the electromagnetic valve 82. The solenoid valve 82 is a normally closed solenoid valve that shuts off the supply of fluid to the cylinder 220 when no control current is supplied. The solenoid portion 83, the cylindrical sleeve 84, and a spool accommodated in the sleeve 84. A valve 85 and a return spring 86 as a biasing member that biases the spool valve 85 toward the solenoid portion 83 are provided. The solenoid unit 83 operates upon receiving a control current supplied from the control device 9, and presses the spool valve 85 to one side in the axial direction (the return spring 86 side) with a pressing force corresponding to the magnitude of the control current.

  The solenoid valve 82 is used in a state in which the sleeve 84 is fitted in a fitting hole 890 formed in the valve body 89. The valve body 89 includes a supply passage 891 for supplying hydraulic oil from the pump 81, an output passage 892 that guides the hydraulic oil to the cylinder 220 side, and a drain passage 893 that guides excess hydraulic oil to the reservoir 810 (not shown). Is formed.

  The sleeve 84 is provided with a valve hole 840 for accommodating the spool valve 85. A spool valve 85 is accommodated in the valve hole 840 so as to be movable in the axial direction. FIG. 5 shows a state in which no control current is supplied to the solenoid portion 83 above the central axis C of the valve hole 840, and a rated control current is supplied to the solenoid portion 83 below the central axis C. Shows the state.

  The sleeve 84 is provided with a supply port 841 communicating with the supply passage 891, an output port 842 communicating with the output passage 892, and a drain port 843 communicating with the drain passage 893. The supply port 841 and the output port 842 are each equipped with a strainer 844 that suppresses the flow of foreign matter. A screw portion 845 is provided at the end of the sleeve 84 opposite to the solenoid portion 83. One end of the valve hole 840 is closed by a plug body 87 screwed into the threaded portion 845, and a return spring 86 made of a coil spring is axially provided between the plug body 87 and the axial end surface of the spool valve 85. Arranged in a compressed state.

  The spool valve 85 is formed with first and second lands 851 and 852. The flow path area between the output port 842 and the supply port 841 changes as the first land 851 moves along the central axis C of the valve hole 840, and the pressure of the hydraulic oil output from the output port 842 Varies depending on the flow path area. Further, the flow path area between the output port 842 and the drain port 843 changes as the second land 852 moves along the central axis C of the valve hole 840.

  The plug body 87 is provided at a disc-shaped base portion 871 with which one end of the return spring 86 abuts, a projection 872 that protrudes toward the spool valve 85, and a peripheral portion of the base portion 871. And a cylindrical portion 873 that is screwed into the threaded portion 845 of the sleeve 84. The spool valve 85 is formed with a receiving hole 850 that opens at the end opposite to the solenoid 83, and a cylindrical blocking member 88 is received in the receiving hole 850 so as to be movable in the axial direction. The accommodation hole 850 extends along the central axis C, and an end on the bottom side thereof and the output port 842 communicate with each other through a communication path 853. The movement of the closing member 88 toward the opening side of the accommodation hole 850 is regulated by the protrusion 872 of the plug 87. The pressure of the hydraulic oil introduced into the accommodation hole 850 from the communication path 853 becomes a feedback pressure that presses the spool valve 85 toward the solenoid part 83.

  The solenoid 83 receives a magnetic flux generated by the solenoid case 831 fixed to the sleeve 84, a bobbin 832 held by the solenoid case 831, an electromagnetic coil 833 wound around the bobbin 832, and a magnetic flux generated by the electromagnetic coil 833. A cylindrical plunger 834 that moves in the axial direction with respect to the case 831, a shaft 835 that axially moves integrally with the plunger 834 and presses the spool valve 85, and a shaft 835 that is inserted into the solenoid case 831. Solenoid core 836.

  In the solenoid valve 82, when no control current is supplied to the solenoid coil 833, the shaft 835 receives the urging force of the return spring 86 via the spool valve 85, and the rear end of the shaft 835 contacts the bottom 831a of the solenoid case 831. Touch. At this time, communication between the supply port 841 and the output port 842 is blocked, and the output port 842 and the drain port 843 communicate with each other.

  On the other hand, when a control current is supplied to the electromagnetic coil 833, the plunger 834 moves to the sleeve 84 side by the magnetic force of the electromagnetic coil 833. Along with this, the shaft 835 moves the spool valve 85 in the axial direction against the urging force of the return spring 86. As a result, the supply port 841 and the output port 842 communicate with each other, the communication between the output port 842 and the drain port 843 is blocked, and the hydraulic oil supplied to the supply passage 891 is output to the output passage 892.

(Configuration of control device and control method)
The control device 9 controls the mesh clutch 12 (see FIG. 1) so as to operate in cooperation with the hydraulic unit 8. The control device 9 is in a two-wheel drive state in which driving force is transmitted only to the front wheels 104L and 104R. During the travel, the engagement of the mesh clutch 12 with the first rotating member 121 and the second rotating member 122 is released, and the hydraulic unit 8 is controlled to release the friction clutch 53 of the driving force transmission device 5 so that the driving force is not transmitted. State. Thus, even when the four-wheel drive vehicle 1 is traveling, the rotation of the propeller shaft 108 stops, and the gear oil agitation resistance in the meshing portion between the pinion gear 108a and the ring gear 108b and the meshing portion between the pinion gear shaft 32 and the ring gear 44 is detected. As a result, the running resistance due to the vehicle is reduced, and the fuel efficiency of the four-wheel drive vehicle 1 is improved.

  Further, when the vehicle behavior becomes unstable due to slippage of one or both of the front wheels 104L and 104R during traveling in the two-wheel drive state, the control device 9 is driven by the control of the hydraulic unit 8. The force transmission device 5 is operated to transmit the rotational force of the rear wheels 105L and 105R to the pinion gear shaft 32 via the differential gear mechanism 4 to rotate the propeller shaft 108. Then, when the rotation of the first rotating member 121 and the second rotating member 122 of the meshing clutch 12 is synchronized, the control device 9 controls the meshing clutch 12 to connect the first rotating member 121 and the second rotating member 122. The sleeves 123 are connected. As a result, the driving force of the engine 102 can be transmitted from the drive shafts 107L and 107R to the rear wheels 105L and 105R via the meshing clutch 12, the propeller shaft 108, and the driving force distribution device 13. Thereafter, the control device 9 adjusts the driving force transmitted to the rear wheels 105L and 105R under the control of the hydraulic unit 8.

  As shown in FIG. 4, the control device 9 includes a storage unit 90 that is a storage unit including a semiconductor storage element, a control unit 91 that is an arithmetic element such as a CPU, and a drive current output that outputs a drive current to the electric motor 80. And a control current output unit 93 that outputs a control current to the electromagnetic valve 82.

  The control unit 91 functions as a normal control unit 911, an abnormality determination unit 912, and an alarm unit 913 by causing the CPU to execute a program stored in the storage unit 90. The drive current output unit 92 includes a plurality of switching elements, and supplies a three-phase alternating current as a drive current to the electric motor 80 by PWM control, for example. Similarly, the control current output unit 93 outputs a control current to the electromagnetic valve 82 by PWM control using a switching element. Note that some or all of the functions of the normal control unit 911, the abnormality determination unit 912, and the alarm unit 913 may be realized by hardware such as an ASIC.

  The normal control unit 911 switches between the two-wheel drive state and the four-wheel drive state as described above according to the vehicle running state and adjusts the driving force transmitted to the rear wheels 105L and 105R in the four-wheel drive state. Control. Further, the normal control unit 911 calculates the target rotation speed of the electric motor 80 and performs feedback control so that the actual rotation speed of the electric motor 80 detected by the rotation speed sensor 801 approaches the target rotation speed. The normal control unit 911 calculates the target rotational speed of the electric motor 80 based on, for example, the amount of depression of the accelerator pedal or the rotational speed difference between the front wheels 104L and 104R and the rear wheels 105L and 105R.

  The abnormality determination unit 912 generates an abnormality in the electromagnetic valve 82 when the operating state of the electric motor 80 when the control current supplied to the electromagnetic valve 82 is changed while the electric motor 80 is operating does not change beyond a threshold value. The abnormality determination control that determines that the error has occurred is executed. When the abnormality determining unit 912 determines that an abnormality has occurred in the electromagnetic valve 82, the alarm unit 913 outputs an abnormality signal indicating the occurrence of abnormality, for example, a warning light on the instrument panel of the four-wheel drive vehicle 1 The driver is informed of the occurrence of an abnormality by lighting it.

  FIG. 6 is a flowchart illustrating an example of a procedure of abnormality determination control executed by the control unit 91 as the abnormality determination unit 912. 7A and 7B show the operating state of the electric motor 80 and the change in the control current supplied to the electromagnetic valve 82 when no abnormality has occurred in the electromagnetic valve 82 during the execution of abnormality determination control. It is a graph. FIGS. 8A and 8B show the operating state of the electric motor 80 and the change in the control current supplied to the electromagnetic valve 82 when an abnormality has occurred in the electromagnetic valve 82 during the execution of the abnormality determination control. It is a graph. 7 and 8, (a) shows the change in the rotational speed of the electric motor 80, and (b) shows the change in the control current supplied to the electromagnetic valve 82. Moreover, the horizontal axis of the graphs of FIGS. 7 and 8 is a time axis.

  The outline of the abnormality determination control executed by the control unit 91 as the abnormality determination means 912 is as follows. That is, when the control current supplied to the electromagnetic valve 82 is changed from the first current value to the second current value during the operation of the electric motor 80, and the control current supplied to the electromagnetic valve 82 is changed from the second current value to the first current value. It is determined that an abnormality has occurred in the electromagnetic valve 82 when the operating state of the electric motor 80 does not change beyond the threshold value at least in any one of returning to the current value. Further, in the present embodiment, the abnormality determination control is executed while the piston 7 is moving forward and before the pressing force of the piston 7 applied to the friction clutch 53 increases.

  In the present embodiment, the rotational speed (actual rotational speed) of the electric motor 80 is used as the operating state of the electric motor 80 that serves as a reference for determination by the abnormality determining means 912. That is, an abnormality has occurred in the electromagnetic valve 82 when the change in the rotational speed of the electric motor 80 when the control current supplied to the electromagnetic valve 82 is changed during operation of the electric motor 80 does not change beyond the threshold value. Is determined. That is, when the load (rotational resistance) of the electric motor 80 is changed by changing the control current supplied to the electromagnetic valve 82, a change appears in the rotational speed of the electric motor 80 if the electromagnetic valve 82 is operating normally. If the electromagnetic valve 82 is not operating normally, the rotational speed of the electric motor 80 does not change, and therefore whether or not the electromagnetic valve 82 is abnormal can be determined based on the amount of change in the rotational speed of the electric motor 80.

  The control unit 91 executes the process shown in the flowchart of FIG. 6 in a state where there is no relative rotation between the first rotating member 51 and the second rotating member 52. More specifically, the abnormality determination control is executed when the four-wheel drive vehicle 1 is in a two-wheel drive state and in a steady traveling state where the vehicle travels straight at a constant speed, or while the vehicle is stopped. Further, the abnormality determination control may be executed when switching from the two-wheel drive state to the four-wheel drive state. By executing the processing of the flowchart shown in FIG. 6 at such timing, the abnormality determination control can be executed without causing the driving force transmission system 101 to generate sound or vibration due to impact. Note that, at the start of the processing of the flowchart in FIG. 6, a first timer counter and a second timer counter, which will be described later, are initially set to zero, and the first confirmation flag and the second confirmation flag are in an off state.

  In the process shown in the flowchart of FIG. 6, the abnormality determination unit 921 first operates the electric motor 80 (step S1). Specifically, the target rotational speed of the electric motor 80 is changed from zero to a predetermined value, and supply of drive current to the electric motor 80 is started. Thereby, the pump 81 is driven. At the same time, the abnormality determination unit 921 sets the control current supplied to the electromagnetic valve 82 as the first current value (step S2). As a result, the supply port 841 and the output port 842 communicate with each other and supply of hydraulic oil to the cylinder 220 is started. In the present embodiment, the rated current value of the solenoid unit 83 is used as the first current value. Note that the processes in steps S1 and S2 do not necessarily have to be performed simultaneously, and any one of the processes may be executed first.

  Next, the abnormality determination unit 921 detects the rotation speed of the electric motor 80 based on the detection signal of the rotation speed sensor 801 (step S3), and determines whether or not the rotation speed of the electric motor 80 has become a predetermined value or more. (Step S4). In this determination, when the rotation speed of the electric motor 80 is less than the predetermined value (S4: No), the processes of step S3 and step S4 are executed again at predetermined time intervals. In addition, after the supply of the drive current to the electric motor 80 is started in step S1, if the rotational speed of the electric motor 80 does not exceed a predetermined value within a predetermined time, the process may proceed to step S18 described later.

  When the rotation speed of the electric motor 80 is equal to or higher than the predetermined value in the determination in step S4 (S4: Yes), the abnormality determination unit 921 sets the control current supplied to the electromagnetic valve 82 as the second current value (step S5). In the present embodiment, the second current value is zero, and the supply of the control current to the electromagnetic valve 82 is cut off by executing the process of step S5, and the communication between the supply port 841 and the output port 842 is cut off. Is done. Thereby, the load of the electric motor 80 becomes large. The first current value may be a value lower than the rated current value of the solenoid unit 83, and the second current value may be a value larger than zero. However, the first current value and the second current value need to be values that cause a change in the rotational speed of the electric motor 80 to be detectable when the electromagnetic valve 82 is normal.

  Next, the abnormality determination unit 921 increments a first timer counter that functions as a timer until the control current supplied to the electromagnetic valve 82 is returned to the first current value (step S6), and uses the detected signal of the rotation speed sensor 801 as a detection signal. Based on this, the rotational speed of the electric motor 80 is detected (step S7), and it is determined whether or not the rotational speed of the electric motor 80 is less than the first threshold (step S8). In this determination, if the rotation speed of the electric motor 80 is less than the first threshold, the first confirmation flag is turned on (step S9), and if it is not less than the first threshold, the first confirmation flag is turned on. do not do.

  Next, the abnormality determination unit 921 determines whether or not the first timer counter has a predetermined value (step S10). If the first timer counter does not have the predetermined value (S10: No), step S6 is performed. The subsequent processing is executed again. On the other hand, if the timer counter has reached the predetermined value (S10: Yes), the abnormality determination unit 921 returns the control current supplied to the electromagnetic valve 82 to the first current value (step S11).

  As a result, the supply port 841 and the output port 842 of the electromagnetic valve 82 communicate with each other, and the hydraulic oil easily flows into the cylinder 220, thereby reducing the load on the electric motor 80. Thus, in the present embodiment, the control current supplied to the electromagnetic valve 82 is temporarily changed so that the hydraulic oil supplied to the cylinder 220 decreases. More specifically, the control current supplied to the electromagnetic valve 82 is temporarily reduced so that the communication between the output port 842 and the supply port 841 is closed by the first land 851.

  Next, the abnormality determination unit 921 increments the second timer counter (step S12), detects the rotation speed of the electric motor 80 based on the detection signal of the rotation speed sensor 801 (step S13), and rotates the electric motor 80. It is determined whether the speed exceeds the second threshold (step S14). If the rotational speed of the electric motor 80 exceeds the second threshold, the second confirmation flag is turned on (step S15).

  Next, the abnormality determination unit 921 determines whether or not the second timer counter is a predetermined value (step S16). If the second timer counter is not the predetermined value (S16: No), step S12 is performed. The subsequent processing is executed again. On the other hand, if the second timer counter is a predetermined value (S16: Yes), the presence or absence of abnormality of the electromagnetic valve 82 is determined based on the first confirmation flag and the second confirmation flag (step S17).

  In the present embodiment, when both the first confirmation flag and the second confirmation flag are on, it is determined that the electromagnetic valve 82 is normal in the process of step S17, and any of the first confirmation flag and the second confirmation flag is determined. If is not on, the electromagnetic valve 82 is determined to be abnormal. When it is determined that the electromagnetic valve 82 is abnormal, the control unit 91 outputs an abnormality signal indicating the occurrence of abnormality as the alarm unit 913 (step S18). Thereby, for example, a warning light on the instruments panel of the four-wheel drive vehicle 1 is turned on, and the driver is notified of the occurrence of an abnormality.

  In the process of step S17, it may be determined that the electromagnetic valve 82 is normal when either the first confirmation flag or the second confirmation flag is on. Moreover, the presence or absence of abnormality of the electromagnetic valve 82 may be determined only by the first confirmation flag or only by the second confirmation flag. When the presence or absence of abnormality of the electromagnetic valve 82 is determined only by the first confirmation flag, the processing related to the second confirmation flag among the above-described processes can be omitted. Moreover, when determining the presence or absence of abnormality of the electromagnetic valve 82 only by the 2nd confirmation flag, the process relevant to a 1st confirmation flag can be abbreviate | omitted among said each process.

In the graphs of FIGS. 7 and 8A, the predetermined value of the rotation speed of the electric motor 80 in step S4 is indicated by V ₀ , and the first and second threshold values in steps S8 and S14 are V ₁ and V ₂ , respectively. Show. The first threshold value and the second threshold value may be fixed values or may be changed according to the temperature of the hydraulic oil. Since the viscosity of the hydraulic oil changes with temperature, it is possible to detect the abnormality with higher accuracy by changing the first threshold value and the second threshold value according to the temperature of the hydraulic oil.

In the graph of FIG. 7B, the time when the control current supplied to the electromagnetic valve 82 in step S2 is the first current value is t ₀ , and the control current supplied to the electromagnetic valve 82 in step S5 is the second current value. the time was t _1, indicates the time in which the control current supplied to the first current value to the solenoid valve 82 at t ₂ in step S11. At times t ₁ and t ₂ , the piston 7 is moving forward.

As shown in FIG. 7, when the electromagnetic valve 82 operates normally, the load of the electric motor 80 is reduced by reducing the control current supplied to the electromagnetic valve 82 at the time t ₁ to the second current value. The rotation speed increases and the rotation speed decreases, and the rotation speed of the electric motor 80 detected by the rotation speed sensor 801 becomes less than the first threshold value V ₁ . Further, by setting the control current supplied to the electromagnetic valve 82 at the time t ₂ to the first current value, the load of the electric motor 80 is reduced and the rotational speed is increased, and the electric motor 80 detected by the rotational speed sensor 801 is detected. rotational speed of exceeding temporarily second threshold V _2. On the other hand, when the electromagnetic valve 82 is abnormal, the load of the electric motor 80 does not change even if the control current supplied to the electromagnetic valve 82 is changed, and the rotation speed of the electric motor 80 does not change. Therefore, the presence or absence of abnormality of the electromagnetic valve 82 can be detected based on the change in the rotation speed of the electric motor 80.

  In the flowchart of FIG. 6, the case where the rotational speed of the electric motor 80 is used as the operating state of the electric motor 80 that is a criterion for the determination by the abnormality determining unit 912 is not limited to this, but the operation of the electric motor 80 is not limited thereto. A driving current may be used as the state. That is, when the control current supplied to the electromagnetic valve 82 decreases and the rotation speed of the electric motor 80 decreases, the drive current increases so that the actual rotation speed approaches the target rotation speed. Further, when the control current supplied to the electromagnetic valve 82 increases and the actual rotational speed of the electric motor 80 exceeds the target rotational speed, the drive current decreases. Therefore, it is possible to detect whether the electromagnetic valve 82 is abnormal based on the magnitude of the drive current supplied to the electric motor 80.

(Modified example of hydraulic unit)
FIG. 9 is a configuration diagram illustrating a configuration of a hydraulic unit 8A according to a modification. In the configuration example of the hydraulic unit 8 illustrated in FIG. 4, the case where the hydraulic oil discharged from the pump 81 is supplied to the cylinder 220 through the electromagnetic valve 82 has been described. However, in the modification illustrated in FIG. Accordingly, hydraulic oil is directly supplied from the pump 81 to the cylinder 220, and an electromagnetic valve 82 </ b> A is disposed in a return oil passage 815 that branches from the oil passage 814 and reaches the reservoir 810.

  As with the electromagnetic valve 82, the solenoid valve 82A changes its valve opening according to the control current supplied from the control device 9, but contrary to the electromagnetic valve 82, when the control current is not supplied. When the valve is opened and the supplied control current is increased, the valve is closed. That is, the electromagnetic valve 82A is a normally open type solenoid valve. In the fully closed state of the electromagnetic valve 82A, the return oil passage 815 is closed, so that the hydraulic oil discharged from the pump 81 is supplied to the cylinder 220 as it is. Further, when the control current supplied to the electromagnetic valve 82A is reduced, the hydraulic oil easily flows to the reservoir 810 via the electromagnetic valve 82A, and when the valve opening is fully opened, the hydraulic oil is not supplied to the cylinder 220.

  Even in such a configuration of the hydraulic unit 8A, since the load of the electric motor 80 varies depending on the magnitude of the control current supplied to the electromagnetic valve 82A, it is possible to detect whether the electromagnetic valve 82A is abnormal as described above. it can.

(Operation and effect of the embodiment)
According to the embodiment described above, the abnormality determination control is executed based on the change in the operating state of the electric motor 80 when the control current supplied to the electromagnetic valve 82 is changed. It becomes possible to detect with accuracy. Further, since the abnormality determination control is executed in a state where there is substantially no relative rotation between the first rotating member 51 and the second rotating member 52, the driver and passengers feel uncomfortable due to the sound and vibration of the driving force transmission system 101. Can be suppressed.

(Appendix)
As mentioned above, although this invention was demonstrated based on embodiment, these embodiment does not limit the invention which concerns on a claim. In addition, it should be noted that not all the combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

  Further, the present invention can be appropriately modified and implemented without departing from the spirit of the present invention. For example, the configurations of the driving force transmission system 101, the driving force distribution device 13, and the electromagnetic valve 82 of the four-wheel drive vehicle 1 are not limited to those illustrated in FIG. 1 to FIG. Is possible.

DESCRIPTION OF SYMBOLS 1 ... Four-wheel drive vehicle 10 ... Press apparatus 100 ... Fluid supply apparatus 51 ... 1st rotation member 52 ... 2nd rotation member 53 ... Friction clutch 7 ... Piston 8, 8A ... Hydraulic unit 80 ... Electric motor 81 ... Pumps 82, 82A ... Solenoid valve 9 ... Control device

Claims (7)

An electric motor that operates according to the supplied drive current, a pump that is driven by the electric motor, an electromagnetic valve whose valve opening changes according to the supplied control current, and the drive current that is supplied to the electric motor And a control device that supplies the control current to the electromagnetic valve, and a fluid supply device that supplies the fluid discharged from the pump to the supply target by adjusting the valve opening degree,
The controller determines that an abnormality has occurred in the electromagnetic valve when the operating state of the electric motor when the control current is changed during operation of the electric motor does not change beyond a threshold value. Execute judgment control,
Fluid supply device. The control device, when executing the abnormality determination control, when changing the control current from the first current value to the second current value, and when returning from the second current value to the first current value Among them, it is determined that an abnormality has occurred in the electromagnetic valve when the operating state of the electric motor does not change beyond a threshold value in at least any one of them,
The fluid supply apparatus according to claim 1. A pressing device comprising: the fluid supply device according to claim 1; and a piston that moves forward by the pressure of a cylinder to which fluid is supplied from the fluid supply device, wherein the pressing object is pressed by the piston.
The control device performs the abnormality determination control while the piston is moving forward and before the pressing force of the piston applied to the pressing object increases.
Pressing device. The pressing object is a friction clutch that transmits a driving force from an input rotating member to an output rotating member in a vehicle,
The control device executes the abnormality determination control in a state where there is no relative rotation between the input rotation member and the output rotation member.
The pressing device according to claim 3. The object to be pressed is a friction clutch that transmits a driving force to the auxiliary driving wheel side in a four-wheel drive vehicle including a main driving wheel and an auxiliary driving wheel.
The controller determines the abnormality determination control when shifting from a two-wheel drive state in which driving force is transmitted only to the main driving wheel to a four-wheel driving state in which driving force is transmitted to the main driving wheel and auxiliary driving wheel. Run the
The pressing device according to claim 3. The control device executes the abnormality determination control by temporarily changing the control current so that the fluid supplied to the cylinder decreases during the forward movement of the piston.
The pressing device according to any one of claims 3 to 5. The solenoid valve is a normally closed solenoid valve that is disposed between the pump and the cylinder and shuts off the supply of fluid to the cylinder when the control current is not supplied.
The control device, when executing the abnormality determination control, temporarily decreases the control current so that the electromagnetic valve is in a closed state,
The pressing device according to claim 6.

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