JP5344057B2 - Piston type pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump in which a volume of a fluid chamber in/from which a fluid is sucked and discharged by operation of one operation member can be changed. <P>SOLUTION: The piston type pump includes first and second members which are rotatable relatively to each other, a cam provided on the first member, the operation member attached to the second member and the fluid chamber provided in the second member, In the piston type pump, the fluid chamber is constituted of divided chambers, a control mechanism controlling connection of passages for sucking the fluid into the divided chambers for each of divided chambers is provided, and a first pump controlling means (step S7) controlling connection of the passages by the control mechanism so that the flow rate of the fluid sucked into the divided chambers does not exceed a predetermined flow rate value when difference between the numbers of rotation of the first and second members is made high. <P>COPYRIGHT: (C)2012,JPO&amp;INPIT

Description

  The present invention relates to a piston-type pump configured to operate along the shape of a cam while the piston is in contact with the cam.

  2. Description of the Related Art Conventionally, a piston-type liquid device is known in which a piston is operated by relative rotation between a first member and a second member, and a liquid enters and exits a fluid chamber. An example of this piston-type liquid device is described in Patent Document 1. In the radial piston motor described in Patent Document 1, an output shaft is disposed in a housing. A ring-shaped cam is fixed to the housing, and an inner cam surface is formed on the cam. The output shaft is formed with a plurality of bores in the circumferential direction, and each bore houses a piston that operates in the radial direction of the output shaft. Each piston is provided with a roller, and the roller is configured to roll on the inner cam surface. Further, an oil hole is connected to the bore. Then, oil is supplied to the bore through the oil hole, the piston reciprocates in the bore, and the roller attached to the piston rolls on the inner cam surface, so that the output shaft is taken out as a rotational motion.

JP 2004-190522 A

  By the way, in the radial piston motor described in Patent Document 1, the flow rate of oil supplied to the bore cannot be changed when one piston operates. For this reason, when this radial piston motor is used as a pump, the urging force applied to the piston becomes insufficient, and the piston may be separated from the cam surface (climbing).

  The present invention has been made against the background of the above circumstances, and provides a variable displacement piston type pump capable of changing the volume of fluid sucked and discharged into the fluid chamber by the operation of one piston. In addition, an object of the present invention is to provide a piston-type pump capable of suppressing the movement member from separating from the cam (mountain jump).

The piston-type pump has a first member and a second member that are relatively rotatable about a rotation axis, and a shape that is provided on the first member and is displaced in a predetermined direction. A cam that is attached to the second member and is operable in a predetermined direction in contact with the cam; provided in the second member; and the first member A piston type pump comprising a fluid chamber into which fluid is sucked and discharged by the operation of the operation member when the member and the second member rotate relative to each other, wherein the fluid chamber is a single operation member The fluid is sucked and discharged by the operation, and is composed of a plurality of divided chambers that are fluid-tightly divided from each other, connected to each of the plurality of divided chambers, and a passage through which the fluid passes, This passage is connected to each of the plurality of divided chambers. Separately control mechanism for opening and blocking is provided et al is, when the rotational speed difference between the first and second members is increased, the flow velocity of the fluid to be sucked into the plurality of divided chambers, so as not to exceed a predetermined flow rate value, and is characterized in that you are provided with a first pump control means for controlling the opening and blocking of the passage by the control mechanism.

According to the present invention, when the first member and the second member rotate relative to each other about the rotation axis, the operation member moves in a predetermined direction while being in contact with the cam. By the operation of the operation member, the fluid is sucked into the fluid chamber and the fluid is discharged from the fluid chamber. In a divided chamber in which a fluid that applies fluid pressure to one operating member is sucked and discharged, connection / cutoff of the passage can be controlled for each divided chamber. For this reason, while being able to change the capacity | capacitance of the fluid discharged from a fluid chamber for every operation member, it is possible to change the flow velocity of the fluid for every channel | path connected to each division | segmentation chamber. . Therefore, it is possible to adjust the urging force that presses the operating member against the cam. In other words, the operation member can be prevented from separating from the cam (mountain jump), and the followability of the operation member to the cam is improved. Further, the amount of fluid discharged from the pump can be made variable, which is equivalent to physically having a plurality of pumps with one pump, and the pump can be reduced in size and cost.

It is a conceptual diagram which shows the specific example 1 of this invention. It is a conceptual diagram which shows the whole structure of a vehicle in the case of using the piston type pump in this invention as a power transmission device for vehicles. It is sectional drawing in the radial direction of the pump shown by FIG. It is a graph which shows the relationship between the various modes which control the pump shown by FIG. 1, and the state corresponding to each mode. It is a flowchart which shows the example of control which switches the mode of the piston type pump in this invention. It is a conceptual diagram which shows the specific example 2 of this invention. It is a conceptual diagram which shows the specific example 3 of this invention. It is a conceptual diagram which shows the structure of the hydraulic control apparatus used for the specific example 3 of this invention. It is a graph which shows the relationship between the various modes which control the oil pump of the specific example 3, and the state corresponding to each mode. It is a top view which shows the structure of the rotary valve used in the specific example 1 and specific example 2 of this invention. It is a top view which shows the structure of the rotary valve used in Example 3 of this invention.

  In the piston-type pump, when the first member and the second member rotate relative to each other, the operating member is reciprocated along the shape of the cam to suck the fluid into the fluid chamber. Discharged. The first member and the second member are disposed so as to be relatively rotatable about the rotation axis. In the piston type pump, at least one of the first member and the second member is configured to be rotatable. In other words, any one of the members may be a fixed structure fixed so as not to rotate. The piston type pump can be used as a power transmission device (specifically, a clutch) in addition to being used as a pump for sucking and discharging fluid. When the pump is used as a power transmission device, power is transmitted between the first member and the second member by the engagement force between the cam and the operating member.

  When the pump is used as a power transmission device, both the first member and the second member are rotatably provided. In the piston-type pump, the rotatable member of the first member or the second member is configured to transmit the power of the power source, and the power of the power source is transmitted to one member. As a result, the first member and the second member rotate relative to each other. Of the first member and the second member, a member provided rotatably, that is, a rotating element includes elements such as a rotating shaft, a gear, a sprocket, a sleeve, a pulley, a carrier, and an annular member. On the other hand, when one member of the pump is fixed in a non-rotatable manner, the fixing element is provided in the casing or housing itself in which the pump is accommodated, the bracket or frame attached to the casing or housing, the casing or housing. And the like. Furthermore, the casing or the housing may be either a structure fixed to the power source or a structure fixed to the vehicle body. Further, when the pump is mounted on a vehicle, any one member may be fixed to the vehicle body itself.

  As a power source, it is possible to use an internal combustion engine which is a power device that converts thermal energy into kinetic energy. Further, as the internal combustion engine, a gasoline engine, a diesel engine, an LPG engine, a methanol engine, or the like can be used. An electric motor can also be used as the power source. An electric motor is a power unit that converts electrical energy into kinetic energy. Further, the electric motor may be either a DC motor or an AC motor. Further, as the electric motor, it is also possible to use a power generation / motor having both power generation functions. Furthermore, it is possible to use both an internal combustion engine and an electric motor as power sources. Furthermore, it is also possible to use a flywheel system as a power source. In the piston-type pump, examples of the predetermined direction include a direction along the rotation axis and a radial direction centered on the rotation axis. When the cam is displaced in the radial direction, the shape of the cam can be a curved surface formed in an annular shape around the rotation axis. As a shape in a plane perpendicular to the rotation axis, a waveform shape, an elliptical shape, a perfect circle shape whose center is eccentric from the rotation axis, and the like can be used. On the other hand, when the cam is displaced in the direction along the rotation axis, a cam displaced in a waveform shape in the direction along the rotation axis, or a cam composed of an elliptical flat surface can be used.

  When the cam is displaced radially in a plane perpendicular to the axis of rotation, the actuating member also moves in the radial direction. The pump in which the operating member moves in the radial direction in this way is a radial piston pump. On the other hand, when the cam is displaced in the direction along the rotation axis, the operating member also moves in the direction along the rotation axis. The pump in which the operation member moves in the direction along the rotation axis is an axial (thrust) piston pump. In the piston type pump, when the first member and the second member are rotated by one rotation relative to each other, the operation member reciprocates once in a predetermined direction, or the operation member is in a predetermined direction. Any configuration that reciprocates twice or more may be used. In the piston-type pump, the operating member has a piston attached to the first member and a rolling element attached to the piston, and the rolling element is configured to contact the cam. A roller or a ball can be used as the rolling element. The concave portion in the piston-type pump is a housing portion that holds the operation member in an operable manner, and includes a cylinder bore, a recess, a hole, and the like. The first step portion and the second step portion in the piston type pump are wall surfaces surrounding (forming) the cylinder chamber.

  The fluid that is driven into the fluid chamber by driving the piston-type pump and the fluid that is discharged from the fluid chamber are incompressible fluids. The incompressible fluid is specifically a liquid, and examples of the liquid include water, oil, antifreeze liquid, chemical liquid, and hot water. When a piston-type pump is used as a power transmission device (clutch), the liquid may be oil. The passage in the piston-type pump is a flow path through which a fluid passes. The passage includes an oil path, a hole, a hole, a groove, a recess, a recess, a valve port, a flow path in the valve and the like. In a piston-type pump, the control mechanism is a mechanism that can connect and shut off the passages, and can open and close the passages themselves. The control mechanism includes a valve body, a valve itself, and this valve. An electronic control unit to control is included. Furthermore, when a piston-type pump is used in a vehicle, the first member and the second member can be arranged in a power transmission path from the driving force source of the vehicle to the wheels. In this case, the pump can be arranged in the space below the floor. It is also possible to arrange a pump in the engine room of the vehicle. For example, it is possible to arrange a pump in the engine room and use it as a pump for sucking and discharging cooling water for cooling the engine or the electric motor. Furthermore, when the piston pump is mounted on the vehicle as an oil pump, the oil supplied to the hydraulic actuator for power steering that controls the steering force of the vehicle can be configured to be supplied from the oil pump. Furthermore, when the piston pump is mounted on the vehicle as an oil pump, the oil supplied to the hydraulic actuator for the suspension device of the vehicle can be configured to be supplied from the oil pump. Furthermore, the pump can be installed in the factory, on the ground, etc. in addition to the vehicle.

  Further, according to the piston type pump, any one of the divided chambers is formed between the first step portion and the second step portion. Further, according to the piston type pump, the operation member operates in the recess. Moreover, the 1st division chamber and the 2nd division chamber of the some division chamber are partitioned off by the 1st protrusion member. Therefore, a plurality of division chambers can be divided with a simple structure. Further, according to the piston type pump, the operating member is pressed against the cam by the spring force of the spring, and the first protruding member is pressed against the second member by the spring. That is, since the spring has both the function of pressing the operating member against the cam and the function of fixing the first protruding member, the work of fixing the first protruding member to the second member in the process of assembling the piston type pump. Can be done easily.

Further, according to the piston type pump, the first and third divided chambers of the plurality of divided chambers are partitioned by the second projecting member. Therefore, a plurality of division chambers can be divided with a simple structure. Further, the operating member can be reduced in size, and as a result, the concave portion can also be reduced in diameter. Further, according to the piston type pump, the flow rate of the fluid discharged from the fluid chamber decreases as the rotational speed difference between the first member and the second member increases. Further, according to the piston-type pump, the operation member provided corresponding to the second frequency dividing chamber of the plurality of divided chambers, when operating in the direction for sucking fluid to a second frequency dividing chamber only , passageway fluid in the second divided chamber of the plurality of divided chambers is discharged, is connected to the second frequency dividing chamber. Therefore, in step operating in the direction for sucking fluid to a second frequency dividing chamber, the fluid pressure of the second split chamber is given to the operation member provided corresponding to the second frequency dividing chamber, the operation The force with which the member is pressed against the cam is increased, and the followability of the operating member to the cam is improved. Further, according to the piston type pump, when the operation member provided corresponding to the first division chamber among the plurality of division chambers operates in a direction to suck the fluid into the first division chamber, and In any case of operating in the direction in which the fluid is discharged from the one divided chamber, a passage through which the fluid in the second divided chamber among the plurality of divided chambers is discharged is connected to the first divided chamber. Therefore, in the stroke in which the operating member operates in the direction of sucking the fluid into the fluid chamber, the fluid pressure of the second divided chamber is introduced into the first divided chamber, while the operating member is discharged in the direction of discharging the fluid from the fluid chamber. In the operation stroke, the fluid is discharged from the first divided chamber and the second divided chamber, so that a decrease in the total amount of fluid discharged from the fluid chamber can be suppressed.

In the piston type pump, the predetermined flow velocity value is a threshold value for determining whether or not the rolling element is separated from the cam. That is, when the flow velocity of the fluid sucked into the fluid chamber exceeds a predetermined flow velocity value, the rolling element may be separated from the cam. Therefore, only when the flow rate of oil sucked into the fluid chamber exceeds a predetermined flow velocity value, the pressure of the fluid in the passage is applied as a force for pressing the operating member of the first divided chamber against the cam. Therefore, it is possible to suppress a decrease in fluid discharge efficiency in the pump. According to the invention of a piston-type pump, when the operation member is operated so as to inhale the fluid into the first division chamber, when connecting the passage of fluid Ru discharged in the second divided chamber into first divided chamber And when the operating member operates to suck fluid into the first divided chamber and when the operating member operates to discharge fluid from the first divided chamber, The fluid discharge amount of the pump can be changed by connecting the passage through which the fluid in the second divided chamber is discharged to the first divided chamber. Further, according to the piston type pump, when the power of the driving force source is transmitted to the first member or the second member, the engagement force between the cam and the operating member causes the first member and the second member to move. Power is transmitted to and from the member.

  Next, a specific configuration example when a piston type pump is used in a vehicle will be described with reference to FIG. FIG. 2 schematically shows an example of the power train and the control system of the vehicle 1. In the vehicle shown in FIG. 2, a piston type pump is used as an oil pump and a clutch. The power train shown in FIG. 2 is a so-called front engine / front drive type power train (two-wheel drive vehicle). An engine 2 is mounted on the vehicle 1. The engine 2 is a driving force source that generates power to be transmitted to the wheels, and is configured such that engine torque is transmitted to the input shaft 4 via the damper mechanism 3. The engine 2 is a power unit that generates torque to be transmitted to the wheels 5, and an internal combustion engine can be used, for example. The damper mechanism 3 is a device that absorbs or mitigates fluctuations in engine torque. The damper mechanism 3 and the input shaft 4 are disposed in a casing (transaxle case) 6. The casing 6 is fastened and fixed to the outer wall of the engine by a fixing mechanism such as a bolt and a nut. The casing 6 is a housing mechanism that houses a rotating element that constitutes a power transmission path, specifically, a rotating shaft, a gear, a pulley, or a bearing that supports these rotating elements. The input shaft 4 is a rotating element that constitutes a part of a power transmission path from the engine 2 to the wheels 5. A rotation axis W <b> 1 of the input shaft 4 is disposed along the left-right direction of the vehicle 1. The torque of the input shaft 4 is transmitted to the belt-type continuously variable transmission 8 via the oil pump 23 and the forward / reverse switching device 7, and the torque output from the belt-type continuously variable transmission 8 is It is configured to be transmitted to the wheel 5 via the transmission device 9 and the final reduction gear 10. Hereinafter, specific examples of the oil pump 23 will be sequentially described.

(Specific example 1)
Specific example 1 of the oil pump 23 will be described with reference to FIGS. 1 and 3. 1 is a longitudinal sectional view in the direction along the rotation axis W1 of the oil pump 23, and FIG. 3 is a sectional view in a plane perpendicular to the rotation axis W1. The rotation axis W1 is common to the rotation axis of the input shaft 4 and the rotation axis of the crankshaft of the engine 2. The oil pump 23 also has a function as a clutch that controls transmission torque between the input shaft 4 and the belt-type continuously variable transmission 8. A rear cover 11 is provided in the casing 6 at a position farthest from the engine 2 in the direction along the rotation axis W1, and the rear cover 11 is provided with a support hole 200 around the rotation axis W1. It has been. The support hole 200 has a cylindrical shape.

  The rotary valve 12 is rotatably supported by the support hole 200. The rotary valve 12 is arranged coaxially with the input shaft 4. As shown in FIG. 10, the rotary valve 12 has a column shape. Discharge ports (oil passages) 14 and 16 and suction ports (oil passages) 13 and 15 are provided on the outer periphery of the rotary valve 12. Is formed. The discharge ports 14 and 16 and the suction ports 13 and 15 are annular grooves formed over the entire circumference of the rotary valve 12, respectively. The discharge ports 14 and 16 and the suction ports 13 and 15 are arranged on the rotation axis W1. They are arranged at different positions along the direction. Further, the rotary valve 12 is formed with oil passages 17, 18, 19, 20 in the direction along the rotation axis W 1, the oil passage 17 and the discharge port 16 are connected, and the oil passage 18 and the suction port 13 are connected. Are connected, the oil passage 19 and the discharge port 14 are connected, and the oil passage 20 and the suction port 15 are connected. Further, in the direction along the rotation axis W1, the suction port 13 and the discharge port 14 are disposed adjacent to each other, and the suction port 15 and the discharge port 16 are disposed adjacent to each other.

  Further, oil passages 52, 53, 59, 60 are formed on the outer peripheral surface of the rotary valve 12. The oil passage 52 is disposed between the suction port 13 and the discharge port 14 in the direction along the rotation axis W <b> 1, and the oil passage 52 is connected to the suction port 13. Further, a plurality of oil passages 52 are provided at regular intervals along the circumferential direction of the rotary valve 12, and six places are provided in this specific example. Further, the oil passage 53 is disposed between the suction port 13 and the discharge port 14 in the direction along the rotation axis W <b> 1, and the oil passage 53 is connected to the discharge port 14. Further, a plurality of oil passages 53 are provided along the circumferential direction of the rotary valve 12 at regular intervals, and in this specific example, six places are provided. Specifically, the oil passages 52 and the oil passages 53 are alternately arranged over the entire circumference of the rotary valve 12. Further, the arrangement region of the oil passage 52 and the oil passage 53 partially overlaps in the direction along the rotation axis W1.

  On the other hand, the oil passage 59 is disposed between the suction port 15 and the discharge port 16 in the direction along the rotation axis W 1, and the oil passage 59 is connected to the suction port 15. Further, a plurality of oil passages 59 are provided along the circumferential direction of the rotary valve 12 at regular intervals, and in this specific example, six places are provided. Further, six oil passages 53 and six oil passages 59 are arranged on the same phase in the circumferential direction of the rotary valve 12. Further, the oil passage 60 is disposed between the suction port 15 and the discharge port 16 in the direction along the rotation axis W 1, and the oil passage 60 is connected to the discharge port 16. Further, a plurality of oil passages 60 are provided at regular intervals along the circumferential direction of the rotary valve 12, and six places are provided in this specific example. Specifically, the oil passages 59 and the oil passages 60 are alternately arranged over the entire circumference of the rotary valve 12. Furthermore, the arrangement region of the oil passage 59 and the oil passage 60 partially overlaps in the direction along the rotation axis W1. Furthermore, in the circumferential direction of the rotary valve 12, six oil passages 60 and six oil passages 52 are arranged on the same phase.

  On the other hand, an annular connecting drum 21 is coaxially arranged outside the input shaft 4. The connecting drum 21 is a connecting member that connects the rotating elements. In addition, a partition wall 22 is provided inside the casing 6, and an oil pump 23 is disposed in a space surrounded by the rear cover 11 and the partition wall 22 in a direction along the rotation axis W <b> 1. A bearing 24 is interposed between the partition wall 22 and the connecting drum 21, and the connecting drum 21 is held by the bearing 24 so as to be rotatable about the rotation axis W1. An outer race 25 that constitutes a part of the oil pump 23 is provided at an end of the connecting drum 21 on the rear cover 11 side. The outer race 25 is a rotating element that constitutes an outer portion of the oil pump 23, and the outer race 25 is coupled to rotate integrally with the connecting drum 21. The outer race 25 includes a flange 26 and a cylindrical portion 27 that is continuous with the end of the flange 26. The flange 26 extends in the radial direction around the rotation axis W <b> 1, and the inner peripheral end of the flange 26 is connected to the connecting drum 21. Further, the cylindrical portion 27 is continuous with the outer peripheral end of the flange 26. The cylindrical portion 27 is provided around the rotation axis W1.

  A cam surface 28 is formed on the inner periphery of the cylindrical portion 27 over the entire periphery. As shown in FIG. 3, the cam surface 28 is formed in an annular shape so as to surround the rotation axis W1 in a plane perpendicular to the rotation axis W1. Further, the cam surface 28 has a concave portion 29 and a convex portion 30 that are displaced in the radial direction around the rotation axis W1. Specifically, a plurality of concave portions 29 and convex portions 30 are provided, and in the circumferential direction of the outer race 25, the concave portions 29 and the convex portions 30 are alternately arranged, and are continuously camped in a waveform shape. 28 is formed. The concave portion 29 is recessed outward in the radial direction, and the convex portion 30 protrudes inward in the radial direction. That is, a plurality of concave portions 29 are formed, and a plurality of convex portions 30 are formed, and the concave portions 29 and the convex portions 30 are connected so as to be smoothly continuous in the circumferential direction. In this way, the circumscribed circle (not shown) in contact with all the concave portions 29 is configured to be larger than the inscribed circle (not shown) in contact with all the convex portions 30. The diameter of the circumscribed circle is configured to be constant in the direction along the rotation axis W1, and the diameter of the inscribed circle is also configured to be constant. In this specific example, six concave portions 29 are provided, and six convex portions 30 are provided.

  Here, the relationship between the arrangement positions of the oil passages 52, 53, 59, and 60 and the arrangement positions of the concave portions 29 and the convex portions 30 in the direction along the rotation axis W1 will be described. The oil passages 52, 53, 59, and 60 are arranged in the same phase as the portion that connects the apex of the convex portion 30 and the bottom of the concave portion 29. In other words, none of the oil passages 52, 53, 59, 60 is arranged in the same phase as the apex of the convex portion 30 and the bottom of the concave portion 29 in the circumferential direction around the rotation axis W 1. Further, a support portion 201 protruding toward the inner peripheral side is connected to an end portion of the cylindrical portion 27 on the rear cover 11 side. The support 201 is formed in an annular shape around the rotation axis W1. The support portion 201 is bent into a crank shape in a plane in the direction along the rotation axis W1. The rotary valve 12 is connected to the inner peripheral end of the support portion 201. The support 201 and the rotary valve 12 are coupled so as to be integrally rotatable, for example, splined. In this way, the outer race 25 and the rotary valve 12 are connected so as to be integrally rotatable. Further, a bearing 202 is interposed between the rear cover 11 and the cylindrical portion 203 of the support portion 201, and the support portion 201 is rotatably supported by the rear cover 11. An inner race 31 is provided inside the outer race 25 configured as described above. The inner race 31 and the input shaft 4 are connected so as to be integrally rotatable, for example, by spline fitting. A bearing 33 is interposed between the cylindrical portion 203 of the support portion 201 and the inner race 31. A bearing 32 is interposed between the inner periphery of the connecting drum 21 and the outer periphery of the inner race 31. The inner race 31 is rotatably supported in the outer race 25 by these bearings 32 and 33. The inner race 31 is formed in a cylindrical shape, and the rotary valve 12 is inserted into the shaft hole 31 </ b> A of the inner race 31.

  Furthermore, a plurality of cylinder bores 34 are formed on the outer periphery of the inner race 31 along the circumferential direction. Each cylinder bore 34 is a substantially cylindrical recess opened on the outer peripheral surface of the inner race 31. In this specific example, eight cylinder bores 34 are arranged at equal intervals. A piston 35 is disposed in each cylinder bore 34, and the piston 35 is configured to be reciprocally movable in the radial direction of the inner race 31 in the cylinder bore 34. That is, the oil pump 23 is a so-called radial piston pump. Further, the rolling elements 36 are held so as to be able to roll at positions closest to the cam surfaces 28 in the respective pistons 35, and the rolling elements 36 come into contact with the cam surfaces 28. That is, the rolling element 36 is attached to the outer end of the piston 35 in the radial direction. The rolling element 36 can be a ball (sphere) or a roller. 1 and 3 show a case where a ball is used as the rolling element 36. Further, the center line R1 of the piston 35 and the cylinder bore 34 is common. The center line R1 is provided in the radial direction along a plane perpendicular to the rotation axis W1. The piston 35 has a disc-shaped portion 37 centered on the center line R1 and a skirt portion 38 continuous to the outer periphery of the disc-shaped portion 37. The rolling element 36 is supported by a disk-shaped portion 37. The skirt portion 38 is a cylindrical portion that extends from the disc-shaped portion 37 in a direction approaching the rotation axis W <b> 1. A ring 39 is provided.

  On the other hand, a recess 40 is provided at the bottom of the cylinder bore 34. A projecting member 41 is disposed between the piston 35 in the cylinder bore 34 and the bottom of the cylinder bore 34. The protruding member 41 is a bottomed cylindrical member, and includes a disk-shaped bottom portion 42 and a cylindrical portion 43 that is continuous with the outer periphery of the bottom portion 42. That is, the cylindrical part 43 continued to the outer peripheral end of the bottom part 42 is provided so as to protrude in the direction along the center line R1. The bottom 42 is disposed in the recess 40. Further, the outer diameter of the cylindrical portion 43 is configured to be smaller than the inner diameter of the skirt portion 38. Further, a compression coil spring 44 is provided in the cylinder bore 34, specifically between the disc-shaped portion 37 and the bottom portion 42. The compression coil spring 44 is arranged to be extendable and contractible in the direction along the center line R1. For this reason, the piston 35 is pressed in the direction along the center line R <b> 1 by the elastic force of the compression coil spring 44 with the bottom 42 disposed in the recess 40 and the protruding member 41 in contact with the inner race 31. The rolling element 36 is pressed against the cam surface 28. For this reason, when the inner race 31 and the outer race 25 rotate relative to each other about the rotation axis W1, the rolling element 36 is centered along the shape of the cam surface 28 in a state where the rolling element 36 is in contact with the cam surface 28. Displacement in the direction along R1. Thus, the piston 35 is configured to reciprocate in the cylinder bore 34 in the direction along the center line R1. A seal ring 45 is attached to the outer periphery of the cylindrical portion 43 of the protruding member 41. The seal ring 45 is configured to contact the inner peripheral surface of the skirt portion 38 to form a seal surface regardless of the position of the piston 35 in the direction along the center line R1 in the cylinder bore 34. Thus, the cylinder chamber A is formed from the inside of the skirt portion 38 to the inside of the cylindrical portion 43, and the cylinder chamber A is sealed in a liquid-tight manner by the seal ring 45. In this way, eight cylinder chambers A are provided. A compression coil spring 44 is disposed in the cylinder chamber A.

  Further, each projecting member 41 is provided with a port 46 that penetrates the bottom 42 thereof. Each port 46 is individually connected to each cylinder chamber A. The inner race 31 is formed with an oil passage 48 connected (communication) to each port 46. The oil passages 48 are provided through the inner race 31 in the radial direction, and the oil passages 48 are provided in the same number as the cylinder chambers A, that is, eight places. The eight oil passages 48 are provided at the same position in the direction along the rotation axis W1. More specifically, the arrangement area of the oil passage 52 and the oil passage 53 overlaps in the direction along the rotation axis W1, and eight oil passages 48 are arranged in the same area as the overlapping area. Yes. For this reason, when the inner race 31 and the rotary valve 12 rotate relative to each other, the oil passage 48 is alternately connected and disconnected with respect to the oil passage 52 and the oil passage 53. Depending on the relative position between the inner race 31 and the rotary valve 12, the oil passage 48 is not connected to either the oil passage 52 or the oil passage 53. Further, the oil passage 48 is not connected to both the oil passages 52 and 53 at the same time.

On the other hand, a cylinder chamber B is formed in the cylinder bore 34 between the outer peripheral surface of the cylindrical portion 43 and the inner peripheral surface of the cylinder bore 34. The cylinder chamber B is formed in an annular shape so as to surround the periphery of the cylindrical portion 43. Further, the cylinder chamber B and the cylinder chamber A are liquid-tightly partitioned by a seal ring 45. Further, the cylinder chamber B and the external space of the cylinder bore 34 are sealed in a liquid-tight manner by a seal ring 39. The pressure receiving area of the piston 35 in the cylinder chamber B is configured to be smaller than the pressure receiving area of the piston 35 in the cylinder chamber A. Therefore, when the piston 35 operates in the radial direction around the rotation axis W1, the change in the volume of the cylinder chamber B is greater than the change in the volume of the cylinder chamber B with respect to the change in the movement amount of the piston 35. Smaller than the amount. In addition, the pressure receiving areas of the pistons 35 are all the same for the plurality of cylinder chambers A, and the pressure receiving areas of the pistons 35 are all the same for the plurality of cylinder chambers B. The pressure receiving area of the piston 35 in the cylinder chamber A is
It can be obtained by the equation of radius ² × circumferential ratio of the inner peripheral surface of the skirt portion 38.

The pressure receiving area of the piston 35 in the cylinder chamber B is
The radius ² of the inner peripheral surface of the cylinder bore 34 × circularity−the pressure receiving area of the piston 35 in the cylinder chamber A can be obtained by the following equation. Further, a compression coil spring 61 is disposed in the cylinder chamber B. The compression coil spring 61 has a configuration that expands and contracts in the direction along the center line R <b> 1, and the elastic force of the compression coil spring 61 generates a load that pushes the piston 35 against the cam surface 28. In the specific example 1, both the hydraulic pressure of the cylinder chamber A and the spring load of the compression coil spring 44 act on the disc-shaped portion 37. On the other hand, both the hydraulic pressure in the cylinder chamber B and the spring load of the compression coil spring 61 act on the end face of the skirt portion 38.

  Furthermore, the inner race 31 is provided with oil passages 55 and 56 individually connected to the cylinder chambers B. Specifically, the oil passage 55 is connected to the cylinder chamber B, and the oil passage 56 is connected to the oil passage 55. The oil passage 55 is extended in the direction along the rotation axis W <b> 1, and the oil passage 56 is extended in the radial direction of the inner race 31. The end of the oil passage 56 is opened on the inner peripheral surface of the shaft hole 31A. Moreover, the opening part of the oil path 56 is arrange | positioned in the area | region where the arrangement area | region of the oil path 59 and the oil path 60 has overlapped in the direction along the rotating shaft W1. In this way, the oil passages 56 are respectively connected to the eight cylinder chambers B, and the eight oil passages 56 are arranged at equal intervals along the circumferential direction of the inner race 31. When the inner race 31 and the rotary valve 12 rotate relative to each other, the oil passage 56 is alternately connected / blocked to / from the oil passage 59 and the oil passage 60. Depending on the relative position between the inner race 31 and the rotary valve 12, the oil passage 56 is not connected to either the oil passage 59 or the oil passage 60. Further, the oil passage 56 is not connected to both of the oil passages 59 and 60 at the same time.

  Next, the configuration of the forward / reverse switching device 7 provided inside the casing 6 will be described. The forward / reverse switching device 7 is disposed between the engine 2 and the oil pump 23 in the direction along the rotation axis W1. The forward / reverse switching device 7 is a device for switching the rotational direction of the primary shaft 60 of the belt-type continuously variable transmission 8 with respect to the rotational direction of the connecting drum 21. In this embodiment, the forward / reverse switching device 7 is switched. The device 7 has a planetary gear mechanism, specifically, a single pinion type planetary gear mechanism. This planetary gear mechanism includes a sun gear 61, a ring gear 62 disposed coaxially with the sun gear 61, and a carrier 64 that holds the sun gear 61 and the pinion gear 63 meshed with the ring gear 62 so as to rotate and revolve. Yes. The sun gear 61 is connected to the primary shaft 60 so as to be able to transmit power, and the ring gear 62 is connected to the connecting drum 21 so as to be able to transmit power. Further, a forward clutch 65 for controlling the connection / release of the rotary elements constituting the forward / reverse switching device 7 is provided, and a reverse brake 66 for controlling the rotation / stop of the rotary elements is provided. The forward clutch 65 controls the connection / release of the sun gear 61 and the ring gear 62, and the reverse brake 66 controls the rotation / stop of the carrier 64.

  Here, as the forward clutch 65, either a friction clutch, an electromagnetic clutch or a meshing clutch may be used, and as the reverse brake 66, either a friction brake, an electromagnetic brake or a meshing brake may be used. In this embodiment, when a friction clutch or a meshing clutch is used and a friction brake or a meshing brake is used, a hydraulically controlled actuator can be used. On the other hand, when an electromagnetic clutch and an electromagnetic brake are used, an electromagnetically controlled actuator is used. In this embodiment, a case where a friction clutch and a friction brake are used and a hydraulically controlled actuator is used will be described. That is, the hydraulic actuator has a hydraulic chamber (not shown), a piston (not shown), and the like, and is generated by the forward clutch 65 and the reverse brake 66 based on the hydraulic pressure in the hydraulic chamber. The braking force is configured to be controlled.

  Next, the belt-type continuously variable transmission 8 will be described. The belt-type continuously variable transmission 8 is provided between the forward / reverse switching device 7 and the damper mechanism 3 in the direction along the rotation axis W1. . The belt type continuously variable transmission 8 has the primary shaft 60 and the secondary shaft 67 described above. The primary shaft 60 is configured to be hollow, and the primary shaft 60 is disposed so as to surround the outside of the input shaft 4. And the input shaft 4 and the primary shaft 60 are comprised so that relative rotation is possible. In the casing 6, partition walls 68, 69 are provided on both sides of the belt-type continuously variable transmission 8 in the direction along the rotational axis W <b> 1 of the input shaft 4, and the primary shaft 60 and the partition walls 68, 69 are separated from each other. A bearing 70 is interposed therebetween. Thus, the primary shaft 60 and the secondary shaft 67 are arranged in parallel to each other, the primary pulley 71 that rotates integrally with the primary shaft 60 is provided, and the secondary pulley 72 that rotates integrally with the secondary shaft 67 is provided. Yes.

  An endless belt 73 is wound around the primary pulley 71 and the secondary pulley 72. Furthermore, a hydraulic servo mechanism 74 that controls the clamping pressure applied from the primary pulley 71 to the belt 73 and a hydraulic servo mechanism 75 that controls the clamping pressure applied from the secondary pulley 72 to the belt 73 are provided. The flow rate and hydraulic pressure of the pressure oil supplied to the hydraulic chambers (not shown) of the hydraulic servo mechanisms 74 and 75 are controlled by a hydraulic control device 76 described later. Further, a transmission device 9 and a final reduction gear 77 for transmitting the torque of the secondary shaft 67 are provided inside the casing 6, and a drive shaft 78 is interposed on the output side of the final reduction gear 77 to drive the wheels. (Front wheel) 5 is connected. As the transmission device 9, a gear transmission device, a winding transmission device, or the like can be used.

  Next, the control system of the vehicle 1 will be described. An electronic control device 79 is provided as a controller for controlling the entire vehicle 1. The electronic control unit 79 includes a sensor for detecting an acceleration request (for example, an operation state of an accelerator pedal) in the vehicle 1, a sensor for detecting a braking request (for example, an operation state of a brake pedal) in the vehicle 1, and an engine speed. Sensor for detecting, sensor for detecting throttle opening, sensor for detecting rotational speed of input shaft 4 and inner race 31, sensor for detecting rotational speed of primary shaft 60, sensor for detecting rotational speed of secondary shaft 67, shift Signals such as a sensor for detecting the position and a sensor for detecting the rotational speed of the outer race 25 are input. On the other hand, the electronic control device 79 outputs a signal for controlling the engine 2, a signal for controlling the hydraulic pressure control device 76, and the like.

  The hydraulic control device 76 includes an oil suction amount and a discharge amount in the oil pump 23, a transmission torque in the oil pump 23, a hydraulic pressure in the hydraulic chamber of the forward clutch 65 and the reverse brake 66, and a hydraulic pressure chamber in the hydraulic servo mechanisms 74 and 75. In addition to controlling the oil pressure and the like, the amount of lubricating oil supplied to the lubrication system is also controlled. Next, the configuration of the hydraulic circuit connected to the cylinder chambers A and B will be described with reference to FIG. An oil pan 80 is provided inside the casing 6 or below or outside the casing 6. Oil (lubricating oil) is stored in the oil pan 80. A suction oil passage 81 is connected to the oil pan 80, and a first switching valve 82 is connected to the suction oil passage 81. The first switching valve 82 can be constituted by a solenoid valve, for example. The first switching valve 82 has five ports 83, 84, 85, 86, 204, the port 83 is always connected to the oil passage 19, the port 84 is always connected to the oil passage 18, and the port 85 is Always connected to the discharge oil passage 87, the port 86 is always connected to the suction oil passage 81, and the port 204 is open to the atmosphere. The oil discharged to the discharge oil passage 87 is supplied to the oil required portion 100.

  Here, the oil required portion 100 includes devices, parts, mechanisms, and the like that are lubricated and cooled by the oil. The devices, parts, and mechanisms that are lubricated and cooled by oil include various bearings, meshing portions of the planetary gear mechanism of the forward / reverse switching device 7, the belt 73 and the pulley of the belt-type continuously variable transmission 8. The contact part etc. are included. The oil required portion 100 includes actuators operated by hydraulic pressure, such as hydraulic servo mechanisms 74 and 75, a hydraulic chamber for controlling the torque capacity of the forward clutch 65, a hydraulic chamber for controlling the braking force of the reverse brake 66, and the like. Is also included. And the 1st switching valve 82 is controlled by the electronic control apparatus 79, The 1st switching valve 82 can select three types of operation states a, b, and c. By selecting the operation state, the pattern for connecting the ports 83 and 84 individually to any of the ports 85, 86, and 204 can be switched, and the ports 85, 86, and 204 can be individually blocked.

  First, when the first switching valve 82 is controlled to the operation state a, the port 83 and the port 85 are connected, the port 84 and the port 86 are connected, and the port 204 is shut off. That is, the discharge port 14 is connected to the discharge oil passage 87 via the oil passage 19. The suction port 13 is connected to the suction oil passage 81 via the oil passage 18. Next, when the first switching valve 82 is controlled to the operation state b, the ports 83 and 84 are both connected to the port 204 and the ports 85 and 86 are shut off. That is, the discharge port 14 and the suction port 13 are both connected to the atmosphere. Further, when the first switching valve 82 is controlled to the operation state c, the ports 83 and 84 are both connected to the port 85 and the ports 86 and 204 are shut off. That is, the discharge port 14 and the suction port 13 are both connected to the discharge oil passage 87.

  On the other hand, a second switching valve 88 is connected to the discharge oil passage 87 and the oil passages 17 and 20. The second switching valve 88 can be constituted by a solenoid valve, for example. The second switching valve 88 has five ports 89, 90, 91, 92, 205, the port 89 is always connected to the suction oil passage 81, the port 90 is always connected to the discharge oil passage 87, and the port 91 is always connected to the oil passage 17, the port 92 is always connected to the oil passage 20, and the port 205 is open to the atmosphere. Then, the second switching valve 88 is controlled by the electronic control unit 79, and four types of operation states d, e, f, and g can be selected. In this operation state, the ports 91 and 92 are individually connected to any one of the ports 89, 90, and 205, and the ports 89, 90, and 205 are individually blocked. First, when the second switching valve 88 is controlled to the operation state d, the port 90 and the port 91 are connected, the port 89 and the port 92 are connected, and the port 205 is shut off. That is, the discharge port 16 is connected to the discharge oil passage 87 via the oil passage 17, and the suction port 15 is connected to the suction oil passage 81 via the oil passage 20. When the second switching valve 88 is controlled to the operation state e, the ports 91 and 92 are both connected to the port 205, and the ports 89 and 90 are both shut off. That is, both the discharge port 16 and the suction port 15 are opened to the atmosphere.

  Further, when the second switching valve 88 is controlled to the operating state f, the ports 91 and 92 are both connected to the port 90 and the ports 89 and 205 are both shut off. That is, the discharge port 16 and the suction port 15 are both connected to the discharge oil passage 87. Further, when the second switching valve 88 is controlled to the operation state g, the port 90 and the port 92 are connected, the port 89 and the port 91 are connected, and the port 205 is shut off. That is, the discharge port 16 is connected to the suction oil passage 81 via the oil passage 17, and the suction port 15 is connected to the discharge oil passage 87 via the oil passage 20. A flow rate control valve 93 is provided in a path directly connecting the suction oil path 81 and the discharge oil path 87. The flow control valve 93 has an input port 94 and a drain port 95, the input port 94 is connected to the discharge oil passage 87, and the drain port 95 is connected to the suction oil passage 81. The flow control valve 93 is a device that returns a part of the discharge oil passage 87 to the suction oil passage 81.

  In the vehicle 1 configured as described above, the function of the oil pump 23 will be described. The spring load of the compression coil springs 44 and 61 is applied to the piston 5, and the piston 35 is pressed outward in the radial direction around the rotation axis W <b> 1, and the rolling element 36 contacts the cam surface 28. Yes. On the other hand, the engine 2 is operated, and the engine torque is transmitted to the input shaft 4 via the damper mechanism 3. The torque of the input shaft 4 is transmitted to the inner race 31 of the oil pump 23. In the first specific example, the oil pump 23 also has a function as a power transmission device in addition to the function of sucking and discharging oil. First, the operation and control when the torque of the input shaft 4 is transmitted to the connecting drum 21 via the oil pump 23 will be described. The oil suction action in the oil pump 23 and the oil discharge action in the oil pump 23 will be described later.

  First, the control of the forward / reverse switching device 7 will be described. When the drive position (forward position) is selected as the shift position, the forward clutch 65 is engaged and the reverse brake 66 is released. Then, the three rotating elements of the planetary gear mechanism constituting the forward / reverse switching device 7 rotate integrally. On the other hand, when the reverse position (reverse position) is selected as the shift position, the reverse brake 66 is engaged and the forward clutch 65 is released. Then, the ring gear 62 becomes an input element, and the stopped carrier 64 becomes a reaction force element, so that the sun gear 61 rotates in the opposite direction to the ring gear 62. In this way, the torque of the connecting drum 21 is transmitted to the primary shaft 60 of the belt type continuously variable transmission 8. When the neutral position or the parking position is selected, the reverse brake 66 is released and the forward clutch 65 is released.

  As described above, when torque is transmitted to the primary shaft 60 of the belt type continuously variable transmission 8, the torque of the primary shaft 60 is transmitted to the secondary shaft 67 via the belt 73. In the belt type continuously variable transmission 8, the hydraulic oil supply state in the hydraulic servo mechanisms 74 and 75 is controlled by the hydraulic control device 76. For example, the flow rate of the pressure oil supplied to the hydraulic servo mechanism 74 is controlled, and the winding radius of the belt 73 in the primary pulley 71 and the winding radius of the belt 73 in the secondary pulley 72 are controlled. The gear ratio of the machine 8, that is, the ratio between the rotation speed of the primary shaft 60 and the rotation speed of the secondary shaft 67 can be controlled steplessly (continuously). In addition to the control of the gear ratio, the clamping force applied from the secondary pulley 72 to the belt 73 is adjusted to control the torque capacity of the belt type continuously variable transmission 8.

  In parallel with the speed ratio control, the required driving force in the vehicle 1 is determined based on the vehicle speed and the acceleration request (for example, accelerator opening), and the target engine output is determined based on the determination result. A target engine speed and a target engine torque that can achieve the target engine output with optimum fuel consumption are obtained. Then, the gear ratio of the belt type continuously variable transmission 8 is controlled so that the actual engine speed approaches the target engine speed. Further, in parallel with the speed ratio control of the belt type continuously variable transmission 8, the actual engine torque is brought close to the target engine torque by controlling the electronic throttle valve. As described above, the engine torque is transmitted to the secondary shaft 67 of the belt type continuously variable transmission 8 via the input shaft 4 and the forward / reverse switching device 7. The torque of the secondary shaft 67 is transmitted to the wheel 5 via the transmission device 9 and the final reduction gear 77.

  Next, the oil suction action in the oil pump 23 and the oil discharge action in the oil pump 23 will be described. This specific example 1 will be described on the assumption that when the engine torque is transmitted to the inner race 31, the inner race 31 rotates clockwise in FIG. When the inner race 31 and the outer race 25 rotate relative to each other, the rolling element 36 rolls along the cam surface 28 while the rolling element 36 is in contact with the cam surface 28. Therefore, each piston 35 reciprocates separately in the radial direction following the shape of the cam surface 28 in a plane perpendicular to the rotation axis W1. By the operation of each piston 35, the volumes of the cylinder chambers A and B formed by the piston 35 change synchronously.

  In the stroke in which the piston 35 moves outward in the radial direction of the inner race 31 (up stroke), the volumes of the cylinder chambers A and B both increase, and the pressure in the cylinder chambers A and B decreases (negative Pressure). On the other hand, in the stroke (down stroke) in which the piston 35 moves inward in the radial direction of the inner race 31, both the volumes of the cylinder chambers A and B are reduced, and the inside of the cylinder chambers A and B is reduced. Pressure increases. In Specific Example 1, since eight pistons 35 are provided along the circumferential direction of the inner race 31, each piston 35 has a different operation position and stroke in the radial direction. FIG. 4 is a chart for explaining the operating states of the first switching valve 82 and the second switching valve 88 and the oil passages communicating with the ports of all the cylinders. In FIG. 4, all the cylinder chambers A are indicated as “cylinder chamber group A”, and all the cylinder chambers B are indicated as “cylinder chamber group B”. This will be described with reference to FIG. FIG. 4 also shows a plurality of modes for selectively switching the operating states of the first switching valve 82 and the second switching valve 88. In the first specific example, the mode 1 to the mode 6 can be selectively switched. The conditions for switching between modes 1 to 6 and the switching control thereof will be described later.

  First, when mode 1 is selected, the first switching valve 82 is controlled to the operating state a, and the second switching valve 88 is controlled to the operating state d. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 16 of the cylinder chamber group B is connected to the discharge oil passage 87, and the suction port 15 of the cylinder chamber group B is connected to the suction oil passage 81. Therefore, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber A group via the suction oil passage 81 and the oil passage 18, and the oil in the oil pan 80 is sucked. The oil is also drawn into the cylinder chamber B group via the oil passage 81 and the oil passage 20. On the other hand, in the downward stroke of the piston 35, the oil in the cylinder chamber A group is discharged to the discharge oil passage 87 via the oil passage 19, and the oil in the cylinder chamber B group passes through the oil passage 17. Then, it is discharged to the discharge oil passage 87. Thus, when mode 1 is selected, “the amount of oil discharged from the oil pump 23” is the amount of oil discharged from the cylinder chamber A group and the amount of oil discharged from the cylinder chamber B group. Is the amount added (indicated by “A + B” in FIG. 4). The “discharge amount of oil discharged from the oil pump 23” is a discharge amount per unit rotational speed difference (when the rotational speed difference is 1) between the inner race 31 and the outer race 25. It has the same meaning in the mode.

  Next, when mode 2 is selected, the first switching valve 82 is controlled to the operating state a, and the second switching valve 88 is controlled to the operating state e. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. On the other hand, the discharge port 16 and the suction port 15 of the cylinder chamber group B are both opened to the atmosphere (indicated by “open” in FIG. 4). For this reason, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber A group via the intake oil passage 81 and the oil passage 18, while in the downward stroke of the piston 35, the cylinder chamber Group A oil is discharged to the discharge oil passage 87 via the oil passage 19. On the other hand, in the cylinder chamber B group, oil suction and oil discharge are not performed. Thus, when mode 2 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber A group (indicated by “A” in FIG. 4).

  Further, when mode 3 is selected, the first switching valve 82 is controlled to the operating state b, and the second switching valve 88 is controlled to the operating state d. Then, the discharge port 14 and the suction port 13 of the cylinder chamber A group are both opened to the atmosphere. On the other hand, the discharge port 16 of the cylinder chamber group B is connected to the discharge oil passage 87, and the suction port 15 of the cylinder chamber group B is connected to the suction oil passage 81. For this reason, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber B group via the suction oil passage 81 and the oil passage 20, while in the downward stroke of the piston 35, the cylinder chamber Group B oil is discharged to the discharge oil passage 87 via the oil passage 17. On the other hand, in the cylinder chamber A group, oil suction and oil discharge are not performed. Thus, when mode 3 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber B group (indicated by “B” in FIG. 4).

  Further, when mode 4 is selected, the first switching valve 82 is controlled to the operation state a, and the second switching valve 88 is controlled to the operation state f. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 16 and the suction port 15 of the cylinder chamber B group are both connected to the discharge oil passage 87. For this reason, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber A group via the suction oil passage 81 and the oil passage 18, while in the downward stroke of the piston 35, the cylinder chamber Group A oil is discharged to the discharge oil passage 87 via the oil passage 19. On the other hand, the oil discharged from the discharge port 16 of the cylinder chamber B is sucked into the cylinder chamber B of the piston 35 in the upward stroke via the suction port 15. That is, when mode 4 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber A group (indicated by “A” in FIG. 4).

  Further, when mode 5 is selected, the first switching valve 82 is controlled to the operation state c, and the second switching valve 88 is controlled to the operation state d. Then, the discharge port 14 and the suction port 13 of the cylinder chamber A group are both connected to the discharge oil passage 87. Further, the discharge port 16 of the cylinder chamber group B is connected to the discharge oil passage 87, and the suction port 15 of the cylinder chamber group B is connected to the suction oil passage 81. Therefore, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber B group via the intake oil passage 81 and the oil passage 20, and in the downward stroke of the piston 35, the cylinder chamber Group B oil is discharged to the discharge oil passage 87 via the oil passage 17. On the other hand, the oil discharged from the discharge port 14 of the cylinder chamber A is sucked into the cylinder chamber A of the piston 35 in the ascending stroke via the suction port 13. That is, when mode 5 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber B group (indicated by “B” in FIG. 4).

  Further, when mode 6 is selected, the first switching valve 82 is controlled to the operating state a, and the second switching valve 88 is controlled to the operating state g. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 16 of the cylinder chamber group B is connected to the suction oil passage 81, and the suction port 15 of the cylinder chamber group B is connected to the discharge oil passage 87. For this reason, in the cylinder chamber A in which the piston 35 is in the upward stroke, the oil in the oil pan 80 is sucked into the cylinder chamber A via the intake oil passage 81 and the oil passage 18 and the piston 35 is in the downward stroke. Is discharged from the cylinder chamber A into the discharge oil passage 87. On the other hand, in the cylinder chamber B where the piston 35 is in the upward stroke, a part of the oil discharged from the cylinder chamber A to the discharge oil passage 87 is sucked into the cylinder chamber B via the oil passage 20. Further, the oil discharged from the cylinder chamber B in which the piston 35 is in the downward stroke is sucked into the cylinder chamber A in which the piston 35 is in the upward stroke via the intake oil passage 81. Thus, when mode 6 is selected, the amount of oil discharged from the oil pump 23 is obtained by subtracting the amount of oil sucked into the cylinder chamber B group from the amount of oil discharged from the cylinder chamber A group. (Indicated by “AB” in FIG. 4).

Here, the relationship between the amounts of oil discharged from the oil pump 23 is as follows.
(Oil discharge amount A + B)> Oil discharge amount A> Oil discharge amount B
And
Oil discharge amount A> (oil discharge amount AB)
It is. In addition, the relationship between (oil discharge amount AB) and oil discharge amount B depends on the design of the volume of cylinder chamber B.
(Oil discharge amount AB) <Oil discharge amount B
Or (oil discharge amount AB)> oil discharge amount B
Or (oil discharge amount AB) = oil discharge amount B
Either of these can be configured. Thus, in the first specific example, the oil discharge amount discharged from the oil pump 23 can be changed (increased or decreased) in a plurality of stages by changing the mode. In this specific example 1, part of the oil discharged to the discharge oil passage 87 can be returned to the intake oil passage 81 via the flow rate control valve 93.

  Next, the urging force applied to the piston 35 in the upward stroke of the piston 35 will be described with reference to FIG. The biasing force applied to the piston 35 is a force that presses the piston 35 outward in the radial direction of the inner race 31. First, when either mode 1 or mode 2 or mode 3 is selected, the biasing force applied to the piston 35 is a biasing force F1 (weak) corresponding to the spring load of the compression coil springs 44 and 61. On the other hand, when mode 4 is selected, the urging force applied to the piston 35 includes the force corresponding to the spring load of the compression coil springs 44 and 61, and “the hydraulic pressure of the discharge oil passage 87 × the piston in the cylinder chamber B”. The urging force F2 (medium) is the sum of the urging forces corresponding to “the area of the pressure receiving surface of 35”. Further, when the mode 5 is selected, the urging force applied to the piston 35 includes the urging force corresponding to the spring load of the compression coil springs 44 and 61, and “the oil pressure of the discharge oil passage 87 × the piston 35 in the cylinder chamber A”. The urging force F3 (large) is the sum of the urging forces corresponding to the “pressure-receiving surface area”. Further, when the mode 6 is selected, the urging force applied to the piston 35 includes the urging force corresponding to the spring load of the compression coil springs 44 and 61, and “the hydraulic pressure of the discharge oil passage 87 × the piston 35 in the cylinder chamber B”. The urging force F2 (medium) is the sum of the urging forces corresponding to the “pressure-receiving surface area”. Note that the urging force applied to the piston 35 in the mode 4 and the urging force applied to the piston 35 in the mode 6 are the same. The biasing force “weak”, biasing force “medium”, and biasing force “large” described here indicate the relative magnitude relationship between the biasing forces. It does not represent a specific value.

  Further, in this specific example 1, the urging force applied to the piston 35 when the piston 35 is in the upward stroke is divided into a plurality of stages, specifically, F1 (weak), F2 (medium), and F3 (large). It can be changed in three stages. As the urging force applied to the piston 35 increases, the rolling element 36 is less likely to be separated from the cam surface 28. In this way, when the rolling element 36 rides over the convex part 30 and rolls toward the concave part 29, it can be prevented that the rolling element 36 is separated from the cam surface 28. Therefore, the followability of the rolling element 36 with respect to the cam surface 28 can be improved, and “the rolling element 36 once leaves the cam surface 28 and then collides with the cam surface 28 to generate noise and vibration” is prevented. it can. Further, in the first specific example, the oil discharge amount in the oil pump 23 can be made variable, which is equivalent to physically having a plurality of pumps with one pump, and the oil pump can be reduced in size and reduced. Cost can be reduced.

  Furthermore, in this specific example 1, by selectively switching between modes 1 to 6, the urging force applied to the piston 35 is changed, and the rolling element 36 can be prevented from separating from the cam surface 28 for each mode. Is different. Therefore, it is possible to selectively switch each mode based on conditions under which it can be determined that the rolling element 36 can be prevented from leaving the cam surface 28. In the oil pump 23, as the rotational speed difference between the inner race 31 and the outer race 25 increases, the rolling element 36 is more easily separated from the cam surface 28, the oil discharge amount in the oil pump 23 increases, and the oil flow rate is increased. Shows an increasing characteristic. In consideration of this characteristic, it is possible to make a determination based on the flow rate of oil sucked into the oil pump 23 when switching the mode. Modes 1 to 3 in which the urging force applied to the piston 35 is F1 (weak) can be selected when the allowable flow velocity value is V1 (low) as shown in FIG.

  Here, the meaning of “allowable flow velocity value” will be described. When the inner race 31 and the outer race 25 rotate relative to each other and the oil is sucked in, the rolling element 36 supported by the piston 35 serving as the suction stroke is the difference in rotational speed that becomes the flow velocity value of the oil. However, it is possible to prevent the cam surface 28 from being separated. For this reason, if the rotational speed difference is such that the oil flow rate becomes an “allowable flow rate value”, it means that the oil pump 23 is allowed to operate. That is, the rotational speed difference considered to be able to prevent the rolling element 36 from being separated from the cam surface 28 is replaced with the flow rate of the oil to be sucked. Further, the difference between the inscribed circle and the circumscribed circle of the cam surface 28, the number of the concave portions 29 and the convex portions 30, the rotational speed difference between the inner race 31 and the outer race 25, the flow rate of the oil sucked into the oil pump 23, the piston An allowable flow velocity value experimentally obtained based on a parameter such as an urging force applied to 35 is converted into data and stored in the electronic control unit 79. The mode 4 or the mode 6 in which the urging force F2 (medium) is applied to the piston 35 can be selected when it is “allowable flow velocity value V2 (medium)” as shown in FIG. Further, the mode 5 in which the urging force F3 (strong) is applied to the piston 35 can be selected when “allowable flow velocity value · V3 (high)” as shown in FIG.

Here, each allowable flow velocity value is
Allowable flow velocity value V3> Allowable flow velocity value V2> Allowable flow velocity value V1
Are in a relationship. In this invention, the higher the "acceptable flow rate value" means that even greater rotational speed difference between the inner race 31 and outer race 25, the rolling element 36 can be prevented from departing from the cam surface 28 To do. In the case of “allowable flow velocity value V3”, if the rotational speed difference between the inner race 31 and the outer race 25 is less than the flow velocity, the rolling element 36 is prevented from separating from the cam surface 28. it can. Further, in the case of “allowable flow velocity value V2”, if the rotational speed difference between the inner race 31 and the outer race 25 is less than the flow velocity, the rolling element 36 is prevented from separating from the cam surface 28. it can. Further, V3 (high), V2 (medium), and V1 (low) shown as allowable flow velocity values indicate relative relationships between the respective flow velocity values, and do not mean a specific flow velocity itself. . Furthermore, the “allowable flow velocity value” has a predetermined range. The “allowable flow velocity value V2” when the mode 4 is selected is the same as the “allowable flow velocity value V2” when the mode 6 is selected.

  Next, a specific control example in the case of switching the mode 1 to the mode 6 will be described based on the flowchart of FIG. First, the connection relationship between the suction port of each cylinder chamber group and the discharge oil passage is determined (step S1). If neither the suction port 14 of the cylinder chamber group A nor the suction port 15 of the cylinder chamber group B is connected to the discharge oil passage 87 at the time of determination in step S1, the allowable flow velocity value is set to V1. It is determined that any one of mode 1 to mode 3 is currently selected (step S2). On the other hand, if the suction port 15 of the cylinder chamber group B is connected to the discharge oil passage 87 at the time of determination in step S1, mode 4 or mode 6 for setting the allowable flow velocity value to V2 is currently selected. (Step S3). Furthermore, when the suction port 14 of the cylinder chamber A group is connected to the discharge oil passage 87 at the time of determination in step S1, the mode 5 for setting the allowable flow velocity value to V3 is currently selected. (Step S4).

  In this way, after determining the currently selected mode, what is the relationship between the flow rate of oil sucked into the cylinder chamber and the range of “allowable flow rate value” in the currently selected mode? It is determined whether the relationship is (high / low relationship) (step S5). In FIG. 5, the process of step S <b> 5 is described as “Is the flow rate of oil sucked into the cylinder chamber within a predetermined value?”. Here, the flow rate of the oil sucked into the cylinder chamber is indirectly determined based on parameters such as the rotational speed difference between the inner race 31 and the outer race 25, the volume of the cylinder chambers A and B, and the number of the cylinder chambers A and B. For example, data obtained by mapping the relationship between the rotational speed difference between the inner race 31 and the outer race 25 and the oil flow velocity is stored in advance in the electronic control unit 79. It is possible to make a judgment in step S5 using. When it is determined that the flow rate of the oil sucked into the cylinder chamber is within the range of “allowable flow velocity value” in the currently selected mode at the time of the determination in step S5 (within the allowable range). Then, the control routine of FIG.

  On the other hand, when the flow rate of the oil sucked into the cylinder chamber is determined to be lower than the “allowable flow rate value” range in the currently selected mode at the time of the determination in step S5. (Less than a predetermined value) is changed to a mode in which “allowable flow velocity value” is smaller than “allowable flow velocity value” in the currently selected mode (step S6), and this control routine is ended. . In step S6, for example, any one of modes 1 to 3 is selected. That is, at the time of determination in step S5, it is determined that the flow rate of the oil sucked into the cylinder chamber is lower than the range of “allowable flow rate value” in the currently selected mode. It is considered that the problem that the rolling element 36 is separated from the cam surface 28 does not occur. Therefore, by changing to the mode in which the “allowable flow velocity value” is smaller (lower) than the “allowable flow velocity value” in the currently selected mode, the force for pressing the rolling element 36 against the cam surface 28 is increased. Decreasing the efficiency of the oil pump 23 is suppressed. Further, at the time of the determination in step S5, when it is determined that the flow velocity of the oil sucked into the cylinder chamber is higher than the range of “allowable flow velocity value” in the currently selected mode (predetermined value). Is greater than “allowable flow velocity value” in the currently selected mode, the “allowable flow velocity value” is changed to a larger (higher) mode (step S7), and this control routine is terminated. .

  In step S7, for example, any one of mode 4 to mode 6 is selected. That is, it is determined that the flow rate of the oil sucked into the cylinder chamber is higher than the range of the “allowable flow rate value” in the selected mode at the time of determination in step S5. There is a possibility that the moving body 36 is separated from the cam surface 28. Therefore, by changing to a mode in which the “allowable flow velocity value” is larger (higher) than the “allowable flow velocity value” in the currently selected mode, the force for pressing the rolling element 36 against the cam surface 28 is increased. It strengthens and prevents the rolling element 26 from leaving | separating from the cam surface 28. FIG. As described above, the reason why the relationship between the mode and the oil flow velocity is set so that the urging force applied to the piston 35 becomes stronger as the oil flow velocity becomes higher is as described above. This is because the rolling element 36 is easily separated from the cam surface 28 and prevents this problem. 4 and 5, the relationship between each mode and the allowable flow velocity value is described. However, instead of the above-described allowable flow velocity value, or in addition to the allowable flow velocity value, the inner race 31 and Each mode can also be configured to be selectively switchable based on the rotational speed difference with the outer race 25.

  Furthermore, in this specific example 1, the oil pump 23 also has a function as a power transmission device. That is, the piston 35 is pressed toward the cam surface 28, and power is transmitted between the inner race 31 and the outer race 25 by the engagement force between the rolling elements 36 and the cam surface 28. If a discharge amount control valve is provided in the discharge oil passage 87, the discharge amount control valve can be controlled when the oil pump is used as a power transmission device. Thus, by controlling the flow resistance of the oil discharged from the oil pump 23, the torque capacity (transmission torque) in the oil pump 23 can be controlled. Specifically, when the flow resistance of the oil discharged from the cylinder chambers A and B is increased, the engagement force between the rolling elements 36 and the cam surface 28 is increased, and the torque capacity of the oil pump 23 is increased. On the contrary, when the flow resistance of the oil discharged from the cylinder chambers A and B is reduced, the force pressing the rolling element 36 against the cam surface 28 is reduced, and the torque capacity of the oil pump 23 is reduced. Thus, when the oil pump 23 is used as a power transmission device, specifically a clutch, the torque capacity is determined based on the engine torque, the gear ratio of the belt type continuously variable transmission 8, and the like.

  In this specific example 1, the required amount of oil in the oil required section 100 is determined by the electronic control unit 79, and modes 1 to 6 are selectively changed based on the determination result, and the oil pump 23 It is also possible to control the oil discharge amount. Specifically, the mode may be selected so that the amount of oil discharged from the oil pump 23 increases in proportion to the increase in required oil amount. Further, in this specific example 1, the vehicle 1 travels by repulsive force, and its kinetic energy passes from the wheel 5 to the outer race 25 of the oil pump 23 via the belt type continuously variable transmission 8 and the forward / reverse switching device 7. Even when the outer race 25 and the inner race 31 are transmitted and rotated relative to each other, the oil pump 23 can suck and discharge oil, and the oil pump 23 can function as a power transmission device. As described above, in the specific example 1, in the cylinder chamber provided corresponding to one piston 35, connection / cutoff of the oil passage or the port can be controlled for each cylinder chamber. Therefore, the volume of oil discharged from the cylinder chamber can be changed for each piston 35. Further, the piston 35 and the rolling element 36 are pressed toward the cam surface 28 by the elastic force of the compression coil spring 44, and the cylindrical member 41 is pressed against the inner race 31 by the compression coil spring 44. That is, since the compression coil spring 44 has both the function of pressing the piston 35 toward the cam surface 28 and the function of fixing the protruding member 41 to the recess 40, the step of fixing the protruding member 41 to the inner race 31. Can be done easily.

  Further, in this specific example 1, even when the difference in rotational speed between the inner race 31 and the outer race 25 becomes large, each mode is set so that the flow rate of oil sucked into the cylinder chambers A and B does not exceed a predetermined value. And the rotational speed difference is determined. Here, the predetermined value is a reference value (threshold value) for determining whether or not the rolling element 36 moves away from the cam surface 28, and when the oil flow rate exceeds a predetermined value, the rolling element 36 moves to the cam surface 38. There is a possibility of leaving. Therefore, according to the specific example 1, it can suppress that the rolling element 26 leaves | separates from the cam surface 28 (mountain jump). Furthermore, in this specific example 1, when mode 6 is selected in step S7 of FIG. 5, the suction port 55 is connected to the discharge oil passage 87 only when the piston 35 operates in the direction of sucking oil into the cylinder chamber B. . For this reason, the oil pressure of the oil in the discharge oil passage 87 is applied to the piston 35 in the upward stroke, and the force for pressing the piston 35 against the cam surface 28 increases, and the followability of the rolling element 36 to the cam surface 28 is improved. To do.

  Further, when the process proceeds to step S7 and mode 4 is selected, either in the case where the piston 35 operates in the direction in which the oil is sucked into the cylinder chamber B or in the case where the piston 35 operates in the direction in which the oil is discharged from the cylinder chamber B. Also, the cylinder chamber B is connected to the discharge oil passage 87. Further, when the mode 5 is selected by proceeding to step S7, either in the case where the piston 35 operates in the direction of sucking oil into the cylinder chamber A or in the case where the piston 35 operates in the direction of discharging oil from the cylinder chamber A. Also, the cylinder chamber A is connected to the discharge oil passage 87. Therefore, when either mode 4 or mode 5 is selected, it is possible to ensure the followability of the rolling element 36 with respect to the cam surface 28 while suppressing a decrease in the amount of oil discharged from the oil pump 23. Furthermore, in this specific example 1, the piston 35 is advanced only when the mode proceeds to step S7 and any one of the modes 4 to 6 is selected, in other words, when the rotational speed difference between the inner race 31 and the outer race 25 becomes large. The urging force given to can be increased. Therefore, in modes 1 to 3, a decrease in the oil discharge efficiency in the oil pump 23 can be suppressed.

  Further, in the first specific example, the inner race 31 is used when only the cylinder chamber in the suction stroke is connected to the discharge oil passage 87 and when the cylinder chamber in the suction stroke and the discharge stroke is connected to the discharge oil passage 87. At least one of the rotational speed difference between the outer race 25 and the outer race 25 or the allowable flow velocity value is changed (different). Therefore, it is possible to secure the pump performance by increasing the oil discharge amount of the oil pump 23 as much as possible. Note that the mode shown in FIG. 4 is a representative example, and any one of the operation states of the first switching valve 82 and any one of the operation states of the second switching valve 88 is selectively combined, and the mode shown in FIG. It is also possible to have a mode not shown. By adopting such a mode, it is possible to change the urging force applied to the piston 35 into more stages.

  The correspondence between the configuration described in the specific example 1 and the configuration of the present invention will be described. The rotation axis W1 corresponds to the rotation axis in the present invention, and the outer race 25 is the “first member” in the present invention. The inner race 31 corresponds to the “second member” in the present invention, the cam surface 28 corresponds to the cam in the present invention, and the radial direction around the rotation axis W1 is “ The piston 35 and the rolling element 28 correspond to the piston in the present invention, the oil corresponds to the fluid in the present invention, and the cylinder chambers A and B correspond to the fluid chamber in the present invention. The cylinder chamber A and the cylinder chamber B correspond to “a plurality of divided chambers” in the present invention, the cylinder chamber A corresponds to the first divided chamber in the present invention, and the cylinder B corresponds to the second divided chamber in the present invention. The suction oil passage 81, the discharge oil passage 87, the oil passages 17, 18, 19, 20, and the ports 83, 84, 85, 86, the ports 89, 90, 91 and 92 correspond to the passage in the present invention, the first switching valve 82, the second switching valve 88, and the electronic control device 79 correspond to the control mechanism in the present invention, and the cylinder bore 34 corresponds to the recess in the present invention. The projecting member 41 corresponds to the first projecting member in the present invention, the engine 2 corresponds to the power source in the present invention, and the compression coil spring 44 corresponds to the “spring” in the present invention.

The correspondence between the functional means shown in FIG. 5 and the configuration of the present invention will be described. Step S7 corresponds to the first pump control means and the fourth pump control means of the present invention. Furthermore, the functional means for executing the control when mode 6 is selected in step S7 corresponds to the second pump control means of the present invention. Furthermore, the functional means for executing the control when mode 4 or mode 5 is selected in step S7 corresponds to the third pump control means of the present invention. Furthermore, the control for changing the rotation speed difference described in steps S3 and S4 corresponds to the allowable flow velocity value changing means of the present invention.

(Specific example 2)
Next, another specific example of the oil pump 23 will be described with reference to FIG. 6, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG. When the specific example 1 and the specific example 2 are compared, the configurations of the piston 35, the cylinder bore 34, and the cylinder chambers A and B are different. In the second specific example, a step portion 101 perpendicular to the center line R <b> 1 is provided in the cylinder bore 34. The step portion 101 is formed in an annular shape over the entire circumference of the cylinder bore 34 around the center line R1. A large-diameter inner peripheral surface 102 and a small-diameter inner peripheral surface 103 are formed on the inner periphery of the cylinder bore 34 with the step portion 101 as a boundary. The large-diameter inner peripheral surface 102 is formed closer to the cam surface 28 in the direction along the center line R1. In addition, the inner diameter of the large-diameter inner peripheral surface 102 is configured to be larger than the inner diameter of the small-diameter inner peripheral surface 103. Furthermore, in the specific example 2, the protruding member 41 described in the specific example 1 is not provided, and the oil passage 48 is directly connected to the cylinder chamber A.

  On the other hand, a large-diameter outer peripheral surface 104 and a small-diameter outer peripheral surface 105 are formed on the skirt portion 38 of the piston 35. The large-diameter outer peripheral surface 104 and the small-diameter outer peripheral surface 105 are arranged at different positions in the direction along the center line R1. The large-diameter outer peripheral surface 104 is disposed closer to the cam surface 28 than the small-diameter outer peripheral surface 105 in the direction along the center line R1. Further, a step portion 106 is formed between the large-diameter outer peripheral surface 104 and the small-diameter outer peripheral surface 105. The step portion 106 is an end surface perpendicular to the center line R1, and is formed in an annular shape centering on the center line R1. Further, the outer diameter of the large-diameter outer peripheral surface 104 is configured to be smaller than the inner diameter of the large-diameter inner peripheral surface 102, and the outer diameter of the small-diameter outer peripheral surface 105 is configured to be smaller than the inner diameter of the small-diameter inner peripheral surface 103. Furthermore, the length of the small-diameter outer peripheral surface 105 is configured to be longer than the length of the small-diameter inner peripheral surface 103 in the direction along the center line R1. In a state where the piston 35 is disposed in the cylinder bore 34, the small-diameter outer peripheral surface 105 is disposed inside the small-diameter inner peripheral surface 103, and the large-diameter outer peripheral surface 104 is disposed inside the large-diameter inner peripheral surface 102. .

  In this way, when the piston 35 is disposed in the cylinder bore 34, the cylinder chamber A is formed in the skirt portion 38, and between the step portion 101 and the step portion 106 in the direction along the center line R1. A cylinder chamber B is formed. A compression coil spring 44 is disposed in the cylinder chamber A, and a compression coil spring 61 is disposed in the cylinder chamber B. Further, a seal ring 39 is attached to the large-diameter outer peripheral surface 104, and the seal ring 39 comes into liquid-tight contact with the large-diameter inner peripheral surface 102 to form a seal surface. Further, a seal ring 107 is attached to the small-diameter outer peripheral surface 105, and the seal ring 107 comes into liquid-tight contact with the small-diameter inner peripheral surface 103 to form a seal surface. In this way, the cylinder chamber B is liquid-tightly sealed by the seal rings 39 and 107. Oil paths 55 and 56 are connected to the cylinder chamber B. The configuration of the hydraulic control device 76 is the same as in the first specific example, and the connection relationship between each oil passage and the cylinder chambers A and B is the same as in the first specific example.

  In the second specific example, the spring load of the compression coil spring 44 and the hydraulic pressure of the cylinder chamber A act on the disk-shaped portion 37. Further, the spring load of the compression coil spring 61 and the hydraulic pressure of the cylinder chamber B act on the step portion 106. In this way, a load is generated in a direction along the center line R <b> 1 so that the piston 35 approaches the cam surface 28. Further, in the specific example 2, in the cylinder chamber A, the pressure receiving area of the piston 35 is configured wider than the pressure receiving area of the piston 35 in the cylinder chamber B. Also in this specific example 2, it is possible to perform switching between the modes 1 to 6 described with reference to FIG. 4, and the operation states of the first switching valve 82 and the second switching valve 88 corresponding to each mode, When the mode is selected, connection / blocking between the suction port 13 and the oil passage 18, connection / blocking between the discharge port 14 and the oil passage 19, connection / blocking between the suction port 15 and the oil passage 20, discharge port 16 Connection / interruption between the oil passage 17 and the oil passage 17, connection / interruption of the suction oil passage 81 and the discharge oil passage 87 with respect to the oil passage 17, connection / disconnection of the port 205 with respect to the oil passage 17, 20, The connection / disconnection of the oil passage 204 with respect to 19, the discharge amount of the oil pump 23, the urging force applied to the piston 35, the allowable flow velocity value, and the like are also the same as in the first specific example. Furthermore, also in the specific example 2, the control of FIG. 5 can be executed. Therefore, also in this specific example 2, the same effect as in specific example 1 can be obtained. Furthermore, in specific example 2, the same effects as in specific example 1 can be obtained for the same components as in specific example 1. The correspondence between the configuration described in the second specific example and the configuration of the present invention will be described. The step portion 106 corresponds to the first step portion of the present invention, and the step portion 101 corresponds to the second step portion of the present invention. It corresponds to.

(Specific example 3)
Next, specific example 3 of the oil pump 23 will be described with reference to FIG. 7, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG. In the third specific example, the protruding member 108 is provided in the skirt portion 38 of the piston 35. The protruding member 108 includes a disk-shaped plate 109 and a columnar portion 110 formed continuously at the center of the plate 109. The columnar part 110 protrudes in a direction along the center line R <b> 1, and the outer diameter of the columnar part 110 is configured to be smaller than the inner diameter of the cylindrical part 43. The front end side of the columnar part 110 is disposed in the cylindrical part 43, and a cylinder chamber A is formed in a space surrounded by the cylindrical part 43, the columnar part 110, and the bottom part 42. A compression coil spring 44 is disposed in the cylinder chamber A. Further, a seal ring 111 is attached to the outer periphery of the column part 110, and the seal ring 111 contacts the inner peripheral surface of the cylindrical part 43 to form a seal surface, thereby sealing the cylinder chamber A in a liquid-tight manner. Also in this specific example 3, the oil passage 48 is connected to the cylinder chamber A through the oil passage 46. In the cylinder chamber A configured as described above, the spring load of the compression coil spring 44 is applied to the end face of the cylindrical portion 110. Further, the hydraulic pressure in the cylinder chamber A acts on the end surface of the cylindrical portion 110. Thus, the load applied to the end surface of the cylindrical portion 110 is transmitted to the piston 35, and the piston 35 is pressed toward the cam surface 28 in the direction along the center line R1. The pressure receiving area of the piston 35 in the cylinder chamber A is
It is obtained by the radius ² × circumference of the inner peripheral surface of the cylindrical portion 43.

Further, an annular cylinder chamber B is formed between the skirt portion 38 and the cylindrical portion 110 of the piston 35. The cylinder chamber A and the cylinder chamber B are partitioned by the cylindrical portion 110. This cylinder chamber B is liquid-tightly sealed by seal rings 45 and 111. A compression coil spring 112 is disposed in the cylinder chamber B. One end of the compression coil spring 112 is in contact with the end face of the cylindrical portion 34, and the other end of the compression coil spring 112 is in contact with the plate 109. The spring load of the compression coil spring 112 is transmitted to the piston 35 via the plate 109, and the piston 35 is pressed toward the cam surface 28 in the direction along the center line R1. Further, the cylindrical portion 43 is provided with an oil passage 113 in a direction along the center line R1. An oil passage 114 that penetrates the inner race 31 in the radial direction is provided, and the oil passage 114 and the oil passage 113 are connected. One end of the oil passage 114 is opened on the inner peripheral surface of the shaft hole 31A. That is, the oil passage 114 is connected to the cylinder chamber B through the oil passage 113. Further, in the inner peripheral surface of the shaft hole 31A of the inner race 31, the opening of the oil passage 48, the opening of the oil passage 57, and the opening of the oil passage 114 are located at different positions in the direction along the rotation axis W1. Has been placed. Specifically, the opening of the oil passage 48 is disposed between the opening of the oil passage 57 and the opening of the oil passage 114. In the cylinder chamber B configured as described above, the spring load of the compression coil spring 112 is applied to the plate 109. Further, the hydraulic pressure in the cylinder chamber B acts on the plate 109. Thus, the load applied to the plate 109 is transmitted to the piston 35, and the piston 35 is pressed toward the cam surface 28 in the direction along the center line R1. The pressure receiving area of the piston 35 in the cylinder chamber B is
(Radius ² of the inner peripheral surface of the skirt portion 38 × circumferential ratio) —determined by the pressure receiving area of the piston 35 in the cylinder chamber A.

  Furthermore, in the third specific example, a cylinder chamber C is formed around the cylindrical portion 43 of the protruding member 41 in the cylinder bore 34. The cylinder chamber A and the cylinder chamber C are partitioned by the protruding member 41. An oil passage 57 is provided in the inner race 31, and one end of the oil passage 57 is connected to the cylinder chamber C. The other end of the oil passage 57 is opened on the inner peripheral surface of the shaft hole 31A. Further, a compression coil spring 61 is disposed in the cylinder chamber C, and the compression coil spring 61 is configured to be extendable and contractible in the direction along the center line R1. The end portion of the compression coil spring 61 in the expansion / contraction direction is in contact with the inner race 31 and the piston 35, and the spring load of the compression coil spring 61 is applied to the piston 35, and the piston 35 is pressed toward the cam surface 28. ing.

For this reason, the hydraulic pressure of the cylinder chamber C and the spring load of the compression coil spring 61 are applied to the end face of the skirt portion 38 of the piston 35. The pressure receiving area of the piston 35 in the cylinder chamber C is
(Radius ² of the inner peripheral surface of the cylinder bore 34 × circularity) −pressure receiving area of the piston 35 in the cylinder chamber A−pressure receiving area of the piston 35 in the cylinder chamber B can be obtained. And in Example 3,
The dimensions of each component are determined so that the pressure receiving area of the cylinder chamber A> the pressure receiving area of the cylinder chamber B> the pressure receiving area of the cylinder chamber C. Therefore, when the piston 35 operates in the direction along the center line R1, the change in the volume of the cylinder chamber A is greater than the change in the volume of the cylinder chamber B with respect to the change in the movement amount of the piston 35. The amount of change in the volume of the cylinder chamber B is larger than the amount of change in the volume of the cylinder chamber C.

  Next, the configuration of the rotary valve 12 in Example 3 will be described with reference to FIG. Discharge ports (oil passages) 14, 209, 208 and suction ports (oil passages) 13, 207, 210 are formed on the outer periphery. The discharge ports 14, 209, 208 and the suction ports 13, 207, 210 are annular grooves formed over the entire circumference of the rotary valve 12, and the discharge ports 14, 209, 208 and the suction ports 13, 207 are respectively formed. , 210 are arranged at different positions in the direction along the rotation axis W1. Furthermore, oil passages 52, 53, 211, 212, 213, and 214 are formed in the rotary valve 12 in the direction along the rotation axis W <b> 1. The oil passage 211 and the discharge port 208 are connected, and the oil passage 212 and the suction port 210 are connected. Further, the oil passage 52 and the suction port 13 are connected, and the oil passage 53 and the discharge port 14 are connected. Further, the oil passage 213 and the discharge port 209 are connected, and the oil passage 214 and the suction port 207 are connected.

  In addition, the oil passage 211 is arranged at six places along the circumferential direction of the rotary valve 12, and the oil passage 212 is arranged at six places along the circumferential direction of the rotary valve 12. Further, the oil passages 211 and 212 are alternately arranged over the entire circumference of the rotary valve 12. Furthermore, the arrangement region of the oil passage 211 and the oil passage 212 partially overlaps in the direction along the rotation axis W1. Furthermore, the opening of the oil passage 57 is arranged in a region where the arrangement region of the oil passage 211 and the oil passage 212 partially overlaps in the direction along the rotation axis W1. Further, the oil passage 52 is arranged at six places along the circumferential direction of the rotary valve 12, and the oil passage 53 is arranged at six places along the circumferential direction of the rotary valve 12. Further, the oil passages 52 and 53 are alternately arranged over the entire circumference of the rotary valve 12. Further, the arrangement region of the oil passage 52 and the oil passage 53 partially overlaps in the direction along the rotation axis W1. Furthermore, the opening of the oil passage 48 is arranged in a region where the arrangement region of the oil passage 52 and the oil passage 53 partially overlaps in the direction along the rotation axis W1.

  The oil passage 213 is arranged at six locations along the circumferential direction of the rotary valve 12, and the oil passage 214 is arranged at six locations along the circumferential direction of the rotary valve 12. Furthermore, the oil passages 213 and 214 are alternately arranged over the entire circumference of the rotary valve 12. Furthermore, the arrangement region of the oil passage 213 and the oil passage 214 partially overlaps in the direction along the rotation axis W1. Furthermore, the opening of the oil passage 114 is arranged in a region where the arrangement region of the oil passage 213 and the oil passage 214 partially overlaps in the direction along the rotation axis W1. Furthermore, in the circumferential direction of the rotary valve 12, six oil passages 52, six oil passages 211, and six oil passages 213 are arranged on the same phase. Furthermore, in the circumferential direction of the rotary valve 12, six oil passages 53, six oil passages 212, and six oil passages 214 are arranged on the same phase. In the third specific example, when the inner race 31 and the rotary valve 12 rotate relative to each other, the oil passage 48 is alternately connected / disconnected to the oil passage 52 and the oil passage 53. Further, when the inner race 31 and the rotary valve 12 are rotated relative to each other, the oil passage 114 is alternately connected / disconnected to the oil passage 213 and the oil passage 214. Further, when the inner race 31 and the rotary valve 12 rotate relative to each other, the oil passage 57 is alternately connected / disconnected to the oil passage 211 and the oil passage 212.

  Further, depending on the relative position between the inner race 31 and the rotary valve 12, the oil passage 48 is not connected to either the oil passage 52 or the oil passage 53. Further, the oil passage 48 is not connected to both the oil passages 52 and 53 at the same time. Further, depending on the relative position between the inner race 31 and the rotary valve 12, the oil passage 114 is not connected to either the oil passage 213 or the oil passage 214. Further, the oil passage 114 is not connected to both of the oil passages 213 and 214 at the same time. Furthermore, when the inner race 31 and the rotary valve 12 rotate relative to each other, the timing at which the oil passage 48 is connected to the oil passage 52, the timing at which the oil passage 114 is connected to the oil passage 213, and the oil passage 57 are oil. The timing for connection to the path 211 is the same. Furthermore, when the inner race 31 and the rotary valve 12 rotate relatively, the timing when the oil passage 48 is connected to the oil passage 53, the timing when the oil passage 114 is connected to the oil passage 214, and the oil passage 57 are oil. The timing for connection to the path 212 is the same.

  Next, the configuration of the hydraulic control device 76 used in the third specific example will be described with reference to FIG. 8, the same components as those in FIG. 1 are denoted by the same reference numerals as those in FIG. A first switching valve 82 and a second switching valve 88 are connected to the suction oil passage 81 and the discharge oil passage 87 as in the first specific example. In the third specific example, the first switching valve 82 is a device that selectively connects the cylinder chamber A to the suction oil passage 81, the discharge oil passage 87, or the atmosphere. Is the same as that of the first specific example. In Specific Example 3, the action when the operation state of the first switching valve 82 is switched is the same as that of Specific Example 1.

  On the other hand, the configuration of the second switching valve 88 is the same as that of the first specific example, and the second switching valve 88 selectively connects the cylinder chamber B to the discharge oil passage 87 or the suction oil passage 81 or the atmosphere. Device. In the connection relationship between the second switching valve 88 and the cylinder chamber B, the difference between the specific example 1 and the specific example 3 will be described. In this specific example 3, the oil passage 213 is connected to the port 91 of the second switching valve 88 with the oil passage 17 and the discharge port 209 interposed therebetween. In the third specific example, the oil passage 214 is connected to the port 92 of the second switching valve 88 with the oil passage 20 and the suction port 207 interposed therebetween. Also in the third specific example, the second switching valve 88 is controlled by the electronic control device 79, and the four types of operation states d, e, f, and g can be selectively switched. First, when the second switching valve 88 is controlled to the operation state d, the port 90 and the port 91 are connected, the port 89 and the port 92 are connected, and the port 205 is shut off. That is, the discharge port 209 is connected to the discharge oil passage 87 via the oil passage 17, and the suction port 207 is connected to the suction oil passage 81 via the oil passage 20. When the second switching valve 88 is controlled to the operation state e, the ports 91 and 92 are both connected to the port 205, and the ports 89 and 90 are both shut off. That is, both the discharge port 209 and the suction port 207 are opened to the atmosphere.

  Further, when the second switching valve 88 is controlled to the operating state f, the ports 91 and 92 are both connected to the port 90 and the ports 89 and 205 are both shut off. That is, the discharge port 209 and the suction port 207 are both connected to the discharge oil passage 87. Further, when the second switching valve 88 is controlled to the operation state g, the port 90 and the port 92 are connected, the port 89 and the port 91 are connected, and the port 205 is shut off. That is, the discharge port 16 is connected to the suction oil passage 81 via the oil passage 17, and the suction port 207 is connected to the discharge oil passage 87 via the oil passage 20.

  Furthermore, in the third specific example, the third switching valve 123 is connected to the discharge oil passage 87 and the suction oil passage 82. The third switching valve 123 is a device that selectively connects the cylinder chamber C to the discharge oil passage 87 or the suction oil passage 81 or the atmosphere. The third switching valve 123 can be constituted by a solenoid valve, for example. The third switching valve 123 has five ports 124, 125, 126, 127, and 215. The port 125 is always connected to the intake oil passage 81, the port 124 is always connected to the discharge oil passage 87, The port 126 is always connected to the discharge port 208 via the oil passage 128, and the port 127 is always connected to the suction port 210 via the oil passage 129. And the 3rd switching valve 123 is controlled by the electronic control apparatus 79, and can selectively switch 4 types of operation states h, i, j, and k. First, when the third switching valve 123 is controlled to the operating state h, the port 124 and the port 126 are connected, the port 125 and the port 127 are connected, and the port 215 is shut off. That is, the discharge port 208 is connected to the discharge oil passage 87 via the oil passage 128, and the suction port 210 is connected to the suction oil passage 81 via the oil passage 129.

  When the third switching valve 123 is controlled to the operation state i, both the port 126 and the port 127 are connected to the port 215, and both the port 124 and the port 125 are blocked. That is, both the discharge port 208 and the suction port 210 are opened to the atmosphere. Further, when the third switching valve 123 is controlled to the operation state j, the ports 126 and 127 are both connected to the port 124, and the ports 125 and 215 are both shut off. That is, the discharge port 208 and the suction port 210 are both connected to the discharge oil passage 87. Further, when the third switching valve 123 is controlled to the operation state k, the port 124 and the port 127 are connected, the port 125 and the port 126 are connected, and the port 215 is shut off. That is, the discharge port 208 is connected to the suction oil passage 81, and the suction port 210 is connected to the discharge oil passage 87.

  Next, the oil suction action and the oil discharge action of the oil pump 23 in the specific example 3 will be described. Also in this specific example 3, it is assumed that the engine torque is transmitted to the inner race 31, and the inner race 31 rotates clockwise in FIG. When the inner race 31 and the outer race 25 rotate relative to each other, the pistons 35 reciprocate in the direction along the operation center line R1, and the volumes of the cylinder chambers A, B, and C change synchronously. In a stroke in which the piston 35 moves outward in the radial direction of the inner race 31 (upward stroke), the volumes of the cylinder chambers A, B, and C are increased, and the pressure in the cylinder chambers A, B, and C is increased. Drops (negative pressure). On the other hand, in the stroke (down stroke) in which the piston 35 moves inward in the radial direction of the inner race 31, the volumes of the cylinder chambers A, B, C are all reduced, and the cylinder chambers A, B , C pressure increases.

  Next, the operating states of the first switching valve 82, the second switching valve 88, and the third switching valve 123, all the cylinder chambers A (referred to as the cylinder chamber A group), and all the cylinder chambers B (referred to as the cylinder chamber B group). The oil passages communicating with the suction port and the discharge port in all the cylinder chambers C (referred to as cylinder chamber C group) will be described with reference to FIG. FIG. 9 is a chart showing a plurality of modes for selectively switching the operating states of the first switching valve 82, the second switching valve 88 and the third switching valve 123. In this specific example 3, mode 1 to mode 7 can be selectively switched. The conditions for switching between modes 1 to 7 may be the same as those in the first specific example. First, when mode 1 is selected, the first switching valve 82 is controlled to the operating state a, the second switching valve 88 is controlled to the operating state d, and the third switching valve 123 is operated to the operating state h. Controlled. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 209 of the cylinder chamber B group is connected to the discharge oil passage 87, and the suction port 207 of the cylinder chamber B group is connected to the suction oil passage 81.

  Further, the discharge port 208 of the cylinder chamber C group is connected to the discharge oil passage 87, and the suction port 210 of the cylinder chamber C group is connected to the suction oil passage 81. Therefore, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber A group via the suction oil passage 81 and the oil passage 18, and the oil in the oil pan 80 is sucked. The oil is also drawn into the cylinder chamber B group via the oil passage 81 and the oil passage 20. Further, the oil in the oil pan 80 is also sucked into the cylinder chamber C group via the suction oil passage 81 and the oil passage 129. On the other hand, in the downward stroke of the piston 35, the oil in the cylinder chamber A group is discharged to the discharge oil passage 87 via the oil passage 19, and the oil in the cylinder chamber B group passes through the oil passage 17. Then, the oil in the cylinder chamber C group is discharged to the discharge oil passage 87 through the oil passage 128. Thus, when mode 1 is selected, the “oil discharge amount” in the oil pump 23 is the amount of oil discharged from the cylinder chamber A group, the amount of oil discharged from the cylinder chamber B group, and the cylinder chamber. This is the sum of the amount of oil discharged from group C (indicated as “A + B + C” in FIG. 9). In the specific example 3 as well, “the amount of oil discharged” is used to mean “the amount of oil discharged per unit rotational speed difference between the inner race 31 and the outer race 25 (rotational speed difference 1)”.

  Next, when mode 2 is selected, the first switching valve 82 is controlled to the operating state a, the second switching valve 88 is controlled to the operating state d, and the third switching valve 123 is set to the operating state i. Be controlled. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 209 of the cylinder chamber B group is connected to the discharge oil passage 87, and the suction port 207 of the cylinder chamber B group is connected to the suction oil passage 81. Further, the suction port 210 and the discharge port 208 of the cylinder chamber C group are both opened to the atmosphere. For this reason, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber A group and the cylinder chamber B group, while in the downward stroke of the piston 35, the cylinder chamber A group and the cylinder chamber B group. Oil is discharged to the discharge oil passage 87. On the other hand, in the cylinder chamber C group, oil is not sucked or discharged. Thus, when mode 2 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber A group and the cylinder chamber B group (indicated by “A + B” in FIG. 9).

  Further, when mode 3 is selected, the first switching valve 82 is controlled to the operating state a, the second switching valve 88 is controlled to the operating state e, and the third switching valve 123 is operated to the operating state i. Controlled. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 209 and the suction port 207 of the cylinder chamber group B are both opened to the atmosphere. Further, the discharge port 208 and the suction port 210 of the cylinder chamber C group are both opened to the atmosphere. Therefore, oil in the oil pan 80 is sucked into the cylinder chamber A group during the upward stroke of the piston 35, while oil in the cylinder chamber A group is discharged into the discharge oil passage 87 during the downward stroke of the piston 35. . On the other hand, in the cylinder chamber B group and the cylinder chamber C group, oil is not sucked / discharged. Thus, when mode 3 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber A group (indicated by “A” in FIG. 9).

  Further, when mode 4 is selected, the first switching valve 82 is controlled to the operating state a, the second switching valve 88 is controlled to the operating state d, and the third switching valve 123 is operated to the operating state j. To be controlled. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 209 of the cylinder chamber B group is connected to the discharge oil passage 87, and the suction port 207 of the cylinder chamber B group is connected to the suction oil passage 81. Further, the discharge port 208 and the suction port 210 of the cylinder chamber C group are both connected to the discharge oil passage 87. Therefore, in the upward stroke of the piston 35, the oil in the oil pan 80 is sucked into the cylinder chamber A group via the suction oil passage 81 and the oil passage 18, and the oil in the oil pan 80 is sucked. The oil is also drawn into the cylinder chamber B group via the oil passage 81 and the oil passage 20. On the other hand, in the downward stroke of the piston 35, the oil in the cylinder chamber A group is discharged to the discharge oil passage 87 via the oil passage 19, and the oil in the cylinder chamber B group passes through the oil passage 17. Then, it is discharged to the discharge oil passage 87. Further, the oil discharged from the cylinder chamber C is sucked into another cylinder chamber C. That is, oil circulates between the cylinder chambers C, and no oil is discharged into the discharge oil passage 87. Thus, when mode 4 is selected, the amount of oil discharged from the oil pump 23 is the sum of the amount of oil discharged from the cylinder chamber A group and the amount of oil discharged from the cylinder chamber B group. (Indicated as “A + B” in FIG. 9).

  Further, when mode 5 is selected, the first switching valve 82 is controlled to the operating state a, the second switching valve 88 is controlled to the operating state e, and the third switching valve 123 is operated to the operating state j. Controlled. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 209 and the suction port 207 of the cylinder chamber group B are both opened to the atmosphere. Further, the discharge port 208 and the suction port 210 of the cylinder chamber C group are both connected to the discharge oil passage 87. Therefore, oil in the oil pan 80 is sucked into the cylinder chamber A group during the upward stroke of the piston 35, while oil in the cylinder chamber A group is discharged into the discharge oil passage 87 during the downward stroke of the piston 35. . On the other hand, in the cylinder chamber group B, oil is not sucked or discharged. Further, the oil discharged from the cylinder chamber C is sucked into another cylinder chamber C. That is, oil circulates between the cylinder chambers C, and no oil is discharged into the discharge oil passage 87. Thus, when mode 5 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber A group (indicated by “A” in FIG. 9).

  Further, when mode 6 is selected, the first switching valve 82 is controlled to the operating state a, the second switching valve 88 is controlled to the operating state f, and the third switching valve 123 is operated to the operating state j. Controlled. Then, the discharge port 14 of the cylinder chamber A group is connected to the discharge oil passage 87, and the suction port 13 of the cylinder chamber A group is connected to the suction oil passage 81. Further, the discharge port 209 and the suction port 207 of the cylinder chamber B group are both connected to the discharge oil passage 87. Further, the discharge port 208 and the suction port 210 of the cylinder chamber C group are both connected to the discharge oil passage 87. Therefore, oil in the oil pan 80 is sucked into the cylinder chamber A group during the upward stroke of the piston 35, while oil in the cylinder chamber A group is discharged into the discharge oil passage 87 during the downward stroke of the piston 35. . On the other hand, the oil discharged from the cylinder chamber B is sucked into the other cylinder chamber B. That is, oil circulates between the cylinder chambers B, and no oil is discharged into the discharge oil passage 87. Further, the oil discharged from the cylinder chamber C is sucked into another cylinder chamber C. That is, oil circulates between the cylinder chambers C, and no oil is discharged into the discharge oil passage 87. Thus, when mode 6 is selected, the amount of oil discharged from the oil pump 23 is the amount of oil discharged from the cylinder chamber A group (indicated by “A” in FIG. 9).

  Further, when mode 7 is selected, the first switching valve 82 is controlled to the operating state b, the second switching valve 88 is controlled to the operating state d, and the third switching valve 123 is operated to the operating state k. To be controlled. Then, the discharge port 14 and the suction port 13 of the cylinder chamber A group are both opened to the atmosphere. Further, the discharge port 209 of the cylinder chamber B group is connected to the discharge oil passage 87, and the suction port 207 of the cylinder chamber B group is connected to the suction oil passage 81. Further, the discharge port 208 of the cylinder chamber C group is connected to the suction oil passage 81, and the suction port 210 of the cylinder chamber C group is connected to the discharge oil passage 87. For this reason, in the cylinder chamber group A, oil is not sucked or discharged. In the cylinder chamber B where the piston 35 is in the upward stroke, the oil in the oil pan 80 is sucked into the cylinder chamber B via the intake oil passage 81 and in the cylinder chamber B where the piston 35 is in the downward stroke. Then, oil is discharged from the cylinder chamber B to the discharge oil passage 87. In contrast, in the cylinder chamber C where the piston 35 is in the upward stroke, a part of the oil discharged from the cylinder chamber B to the discharge oil passage 87 is sucked into the cylinder chamber C. The oil discharged from the cylinder chamber B in which the piston 35 is in the downward stroke is sucked into the cylinder chamber B in which the piston 35 is in the upward stroke via the intake oil passage 81. Thus, when the mode 7 is selected, the oil discharge amount in the oil pump 23 is an amount obtained by subtracting the oil amount sucked into the cylinder chamber C group from the oil amount discharged from the cylinder chamber B group ( FIG. 9 shows “BC”.

In the third specific example, the relationship between the oil discharge amounts in the oil pump 23 is as follows.
(Oil discharge amount A + B + C)> (oil discharge amount A + B)> oil discharge amount A
It is. Thus, also in the specific example 3, the oil discharge amount in the oil pump 23 can be changed (increased or decreased) in a plurality of stages by changing the mode. In the third specific example, part of the oil discharged to the discharge oil passage 87 can be returned to the suction oil passage 81 via the flow rate control valve 93.

  Next, in Example 3, the urging force applied to the piston 35 during the upward stroke of the piston 35 will be described with reference to FIG. When either mode 1, mode 2 or mode 3 is selected, the biasing force applied to the piston 35 is a biasing force F4 (weak) corresponding to the spring load of the compression coil springs 44, 61, 112. On the other hand, when the mode 4 or the mode 5 or the mode 7 is selected, the urging force applied to the piston 35 is equal to the force corresponding to the spring load of the compression coil springs 44, 61, 112, and “discharge oil passage 87. The urging force F5 (medium) is the sum of the urging force corresponding to “the hydraulic pressure of the cylinder 35 × the pressure receiving area of the piston 35 in the cylinder chamber C”. Further, when the mode 6 is selected, the urging force applied to the piston 35 includes a force corresponding to the spring load of the compression coil springs 44, 61, 121, and “the hydraulic pressure of the discharge oil passage 87 × the piston in the cylinder chamber C”. The urging force F6 (strong) is the sum of the urging force corresponding to “35 pressure receiving area” and the urging force corresponding to “hydraulic pressure of the discharge oil passage 87 × pressure receiving area of the piston 35 in the cylinder chamber B”. Note that the urging force F4 (weak), the urging force F5 (middle), and the urging force F6 (strong) described in the specific example 3 indicate the relative strength relationship between the urging forces. It does not represent a specific value of power [Newton].

  Thus, also in the specific example 3, when the piston 35 is in the upward stroke, the urging force applied to the piston 35 is divided into a plurality of stages, specifically, the urging force F4 (weak), the urging force F5 (middle), It is possible to change in three stages of urging force F6 (strong). As the urging force applied to the piston 35 increases, the rolling element 36 is less likely to be separated from the cam surface 28. In this way, when the rolling element 36 rides over the convex part 30 and rolls toward the concave part 29, it can be prevented that the rolling element 36 is separated from the cam surface 28. Therefore, the followability of the rolling element 36 with respect to the cam surface 28 can be improved, and “the rolling element 36 once leaves the cam surface 28 and then collides with the cam surface 28 to generate noise and vibration” is prevented. it can. Therefore, the same effect as in the first specific example can be obtained. In addition, since a part of the piston 25, a part of the protruding member 41, and a part of the protruding member 108 are arranged in the radial direction of the cylinder bore 34 in the cylinder bore 34, the cylinder chambers can be arranged with a simple structure. Can be divided.

  Furthermore, in this specific example 3, by selectively switching between modes 1 to 7, the urging force applied to the piston 35 is changed, and the rolling element 36 can be prevented from leaving the cam surface 28 for each mode. The conditions are different. Therefore, it is possible to selectively switch each mode based on conditions under which it can be determined that the rolling element 36 can be prevented from leaving the cam surface 28. In the oil pump 23, as the rotational speed difference between the inner race 31 and the outer race 25 increases, the rolling element 36 is more easily separated from the cam surface 28, the oil discharge amount in the oil pump 23 increases, and the oil flow rate is increased. Shows an increasing characteristic. In consideration of this characteristic, it is possible to make a determination based on the flow rate of oil sucked into the oil pump 23 when switching the mode. Note that the mode shown in FIG. 9 is a representative example. One of the operating states of the first switching valve 82, one of the operating states of the second switching valve 88, and the operating state of the third switching valve 123 is shown. A mode not shown in FIG. 9 can be obtained by selectively combining any of them. By adopting such a mode, it is possible to change the urging force applied to the piston 35 into more stages.

  The relationship between the configuration described in the specific example 3 and the configuration of the present invention will be described. The cylinder chamber A, the cylinder chamber B, and the cylinder chamber C correspond to the fluid chamber and the plurality of divided chambers in the present invention. A corresponds to the first divided chamber of the present invention, the cylinder chamber C corresponds to the second divided chamber of the present invention, the cylinder chamber C corresponds to the third divided chamber of the present invention, and the first switching valve. 82, the second switching valve 88, the third switching valve 123, and the electronic control device 79 correspond to the control mechanism of the present invention, the protruding member 41 corresponds to the first protruding member of the present invention, and the protruding member 102 The oil passages 128 and 129 and the ports 124, 125, 126, 127, and 215 correspond to the passages of the present invention. The correspondence relationship between the other configurations in the specific example 3 and the configuration of the present invention is the same as the correspondence relationship between the configuration of the specific example 1 and the configuration of the present invention.

Incidentally, Example 1 contains a part of the configuration of the invention of claim 1, 3, 4. Further, the specific example 2 includes a part of the configuration of the invention of the first , second, and fourth aspects. Further, examples 3, that contains a portion of claims 1, 3, 4, 5 of the invention configured. Moreover, although a compression coil spring is used in each specific example, a compression coil spring is used as an elastic member that applies an urging force to the piston 35, but a bamboo child spring can also be used. Furthermore, in the above SL each tool body example, while the first member and the second member is rotated one time relative configuration the piston is several times reciprocating in a predetermined direction of (multi-stroke), the piston The type of pump is mentioned, but the piston type is configured to reciprocate once in a predetermined direction (single stroke) while the first member and the second member rotate relative to each other once. But you can.

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Engine, 8 ... Belt type continuously variable transmission, 17, 18, 19, 20, 128, 129 ... Oil passage, 25 ... Outer race, 28 ... Cam surface, 31 ... Inner race, 34 ... Cylinder bore 35 ... piston, 36 ... rolling element, 41, 108 ... projecting member, 44 ... compression coil spring, 71 ... primary pulley, 72 ... secondary pulley, 73 ... belt, 82 ... first switching valve, 83, 84, 85, 86, 89, 90, 91, 92, 124, 125, 126, 127, 204, 205, 215 ... port, 81 ... suction oil passage, 87 ... discharge oil passage, 88 ... second switching valve, 123 ... third switching Valve, A, B, C ... Cylinder chamber, W1 ... Rotation axis.

Claims (9)

A first member and a second member provided so as to be relatively rotatable about a rotation axis; a cam provided on the first member and having a shape displaced in a predetermined direction; An operation member attached to the second member and operable in a predetermined direction in contact with the cam, provided on the second member, and the first member and the second member A piston-type pump comprising a fluid chamber into which fluid is sucked and discharged by the operation of the operation member when
The fluid chamber is composed of a plurality of divided chambers in which fluid is sucked and discharged by the operation of a single operating member and is fluidly divided from each other.
Are respectively connected to the plurality of divided chambers, and a passage in which the fluid passes, and a control mechanism provided we are for opening and blocking separately this passage for each of the plurality of divided chambers,
The control is performed so that the flow rate of the fluid sucked into the plurality of divided chambers does not exceed a predetermined flow rate value when a difference in rotational speed between the first member and the second member becomes large. First pump control means for controlling opening / closing of the passage by a mechanism is provided.
Piston type pump, wherein the this. Before Symbol a recess is provided in the second member, the operation member are operatively disposed in the recess, the recess includes a first protruding member that protrudes in the direction of movement of said actuating member is provided with, this by first projecting member, a piston-type pump according to claim 1 in which a plurality of divided chambers first division chamber of the second minute split chamber are partitioned. Between the first protruding member and the operation member, provided with a spring which produces a resilient force of the operation direction of the operation member, the first projecting member Re previous SL et pressed against the second member by the spring The piston type pump according to claim 2 . And the second collision out member provided protruding to the operation direction from the operation member, by the second collision detection section member, and a first division chamber of the plurality of divided chamber and the third split chamber The piston-type pump according to claim 3, which is partitioned . Operation member fluid pressure in the second minute split chamber of the plurality of divided chamber acts only when operating in the direction for sucking fluid to the second minute split chamber, first of the plurality of divided chambers a passage which fluid is expelled in two divided chambers, so as to be connected to the second minute split chamber, claims 1 and a second pump control means for controlling the opening and blocking of the passage by the control mechanism 5. The piston type pump according to any one of 4 above. Operation member fluid pressure of the first divided room of the previous SL plurality of divided chamber acts, when operated in the direction for sucking fluid to the first division chamber, and discharges the fluid from the first division chamber in either case of operating in orientation also, by connecting the second division chamber passage which fluid is discharged of the plurality of divided chambers to said first dividing chamber urchin, opening and blocking of the passage by the control mechanism piston type pump according to any one of the third pump controls claims 1 comprises means 5 for controlling. Flow rate of the fluid to be sucked into the fluid chamber, when it exceeds a predetermined flow rate value as the rolling element moves away from the cam, the fluid pressure in the first minute split chamber of the plurality of divided chambers operation member acts, wherein when operating in the direction for sucking fluid to a first minute split chamber, a second dividing chamber fluid passageway said first minute split chamber to be ejected out of the plurality of divided chambers The piston type pump according to claim 5 or 6, further comprising a fourth pump control means for controlling opening / closing of the passage by the control mechanism so as to be connected to the pump.
A case where an oil passage through which the fluid in the second divided chamber is discharged is connected to the first divided chamber when the operation member operates in a direction in which the fluid is sucked into the first divided chamber;
When said operating member in a direction for sucking fluid to the first division chamber is operated, and the in any of when the operating member in a direction for discharging the fluid to operate the first division chamber, before Symbol plurality of split a passageway second minute split chamber of the flow body of the chamber is ejected in the case of connected before Symbol first division chamber,
Wherein the allowable flow rate value changing means for changing the flow rate value determined in advance, a piston-type pump according to claim 7 that example further Bei. The first member and the second member are provided in a power transmission path from the driving force source of the vehicle to the wheels, and the power of the driving force source is transmitted to the first member or the second member. The piston according to any one of claims 1 to 8 , wherein power transmission is performed between the first member and the second member by an engagement force between the cam and the piston. Mold pump.

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