JP2009293578A - Variable displacement fluid pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a variable displacement fluid pump which exerts as little resistance as possible to a flow of fluid. <P>SOLUTION: The variable displacement fluid pump has vanes of which effective heights are changed by moving a movable member. In the variable displacement fluid pump, a drive shaft houses therein an energizing member for energizing the movable member toward one side in a rotating shaft direction, and a control member for moving the movable member in the rotating shaft direction against the energizing member. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention belongs to the technical field of variable displacement fluid pumps used in internal combustion engine cooling systems and the like.

  In recent years, there has been a demand for reducing the supply of cooling water as soon as possible after starting the engine, promoting warm-up and lowering the viscosity of the lubricating oil, thereby improving fuel efficiency and increasing the catalyst temperature to suppress exhaust emissions. There is. In order to satisfy such a requirement, a variable capacity water pump as shown in Patent Document 1 can be considered.

The variable capacity water pump shown in Patent Document 1 is provided with a movable disk that is movable in the axial direction with respect to an impeller having a function of discharging cooling water, and an effective vane due to a change in cooling water pressure accompanying an increase in the number of rotations. The discharge flow rate is made variable by moving the height.
JP-A-2-238198

  However, in the technique described in Patent Document 1, the movable disk is moved against the urging force of the coil spring, and the coil spring is provided in the middle of the flow path of the cooling water. There has been a problem that it becomes a resistance of the cooling water passing near the coil spring.

  The present invention has been made paying attention to the above problems, and it is an object of the present invention to provide a variable displacement fluid pump that gives as little resistance as possible to the flow of fluid.

  In order to achieve the above object, according to the present invention, in the variable displacement fluid pump that changes the effective blade height by moving the movable member, the urging member that urges the movable member to one side in the direction of the rotation axis in the drive shaft. And a control member that moves the movable member in the direction of the rotation axis against the biasing member.

  Since a biasing member such as a coil spring is not disposed in the fluid flow path, the resistance of the fluid can be reduced as much as possible.

  Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.

  1 is a cross-sectional view of a water pump according to a first embodiment, and FIG. 2 is an exploded perspective view of the water pump. The water pump WP of the first embodiment is attached to a water pump attachment port EB1 that opens to the outside of the engine block EB with a bolt. The water pump mounting port EB1 is formed between a cooling water suction port IN (suction portion) and a discharge port OUT (discharge portion) formed in the engine block EB.

  The water pump WP includes a housing 1, a pulley 4, an impeller 6, a movable member 7, a drive shaft 6 a, and a control member 10. The water pump WP is a so-called centrifugal pump that causes a centrifugal force to act on the fluid by the rotation of the drive shaft 6a and discharges the fluid from the center of rotation to the outer peripheral side.

  The housing 1 has a housing cylindrical portion 1a that is inserted into the inner periphery of the water pump mounting port EB1. On the outer periphery of the housing cylindrical portion 1a, there is provided a seal member 1a1 that is liquid-tight with the water pump mounting port EB1. The housing 1 has a square flange portion 1b having one side substantially the same as the diameter of the housing cylindrical portion 1a at a position outside the axial engine block EB when assembled. Bolt holes 1c for fixing the housing 1 to the engine block EB with bolts (not shown) are formed through the four corners of the flange portion 1b on the outer periphery of the housing cylindrical portion 1a (see FIG. 2).

  A hollow support cylinder 1d extends outside the engine cylinder EB in the axial direction of the housing cylinder 1a. The supporting cylindrical portion 1d has a smaller diameter than the outer periphery of the housing cylindrical portion 1a. A bearing 2 is provided on the outer periphery of the supporting cylindrical portion 1d. The axial movement of the bearing 2 is fixed by a step 1d1 formed on the outer periphery of the supporting cylindrical portion 1d and a snap ring 2a. A pulley 4 is rotatably supported via a bearing 2 on the outer periphery of the supporting cylindrical portion 1d. A driving belt for transmitting a rotational driving force between the crankshaft of the engine and the like is stretched around the outer periphery of the small-diameter cylindrical portion 4a of the pulley 4.

  The pulley 4 has a flange portion 4b whose diameter is increased at the end of the small diameter cylindrical portion 4a. A disk-shaped plate member 4c that transmits the rotational driving force transmitted to the pulley 4 to the drive shaft 6a is fixed to the flange portion 4b by a plurality of bolts 4d. A cylindrical connecting portion 4c1 is formed at the center of the plate member 4c. A connecting end 6a1 of a driving shaft 6a described later is inserted into the inner periphery 4c2 of the connecting portion 4c1, and the driving shaft 6a and the plate member 4c are connected by a bolt 4e. The connecting portion 4c1 extends to a position overlapping the supporting cylindrical portion 1d at the axial position.

  A connecting end 6a1 connected to the connecting portion 4c1 of the plate member 4c by a bolt 4e is formed at the end of the drive shaft 6a opposite to the suction port IN. Further, a communication hole 6a11 is formed in the axial center of the connection end 6a1. On the other hand, a fixing portion 6e for fixing the control member 10 is formed on the suction port IN side of the drive shaft 6a. The fixing portion 6e has a comb shape partially extending at three locations in the circumferential direction, and ensures a contact area between the control member 10 and the cooling water. In the fixing portion 6e, a plurality of fixing holes 6e1 serving as female threads of female screws for fixing the control member 10 are formed. This adjusts the initial position of the control member 10 (that is, the spring set load of the coil spring 9). In the first embodiment, three are formed in the axial direction.

  Here, the fixed portion 6e and the control member 10 are arranged so as to face the flow path (suction port IN) through which the cooling water flows, and rotate when the pump is driven, so that the surface shape is as smooth as possible. Is preferred. Therefore, in fixing the control member 10 to the fixing portion 6e, the flow resistance is reduced by employing a headless screw.

  The drive shaft 6 a is rotatably supported by the bearing 3 on the inner periphery of the housing 1. A mechanical seal 5 is attached between the drive shaft 6 a and the inner periphery of the housing 1 on the inlet IN side of the bearing 3. Thus, the suction port IN side of the drive shaft 6a and the outside of the engine block EB are liquid-tightly defined.

  A disc-shaped disc portion 6b is formed between the drive shaft 6a and the fixed portion 6e. A plurality of blades 6c extending in the rotation axis direction are formed on the side surface of the disk portion 6b on the suction port IN side. The disc portion 6b and the blade 6c constitute an impeller 6 including a plurality of blades 6c that are fixed to the drive shaft 6a and extend in the direction of the rotation axis. Further, the disc portion 6b has a plurality of pressure adjusting holes 6d formed on the same circumference (corresponding to the second through portion). In the first embodiment, the drive shaft 6a and the impeller 6 are integrally formed. However, they may be separated and fitted and fixed.

  A movable member 7 is attached to the inlet port IN side of the impeller 6. The movable member 7 is a bottomed cylindrical member that covers the blade 6c from the suction port IN side. The movable member 7 is provided at the center of the rotation axis, a bottom wall portion 7a facing the blade 6c formation surface side of the disc portion 6b, a side wall portion 7b surrounding the outer peripheral side of the impeller 6 on the outer periphery of the bottom wall portion 7a. And a projection 7c inserted into the drive shaft 6a.

  3A is a front view in the axial direction of the movable member 7, and FIG. 3B is a partial cross-sectional view of the blade 6 c of the movable member 7. The bottom wall portion 7a is substantially tapered along the tip shape of the blade 6c. The bottom wall portion 7a is formed with an insertion portion 7g through which the fixing portion 6e is inserted and a groove 7f through which the blade 6c is inserted (see FIGS. 2 and 3). The fixed portion 6e and the insertion portion 7g are configured to be relatively movable in the axial direction and transmit only a force in the rotational direction. Similarly, the blade 6c and the groove 7f are configured to be relatively movable in the axial direction and transmit only a force in the rotational direction. Thereby, the impeller 6 and the movable member 7 are integrally driven in the rotation direction.

  In addition, a minute gap is formed between the groove 7f and the blade 6c. In the bottom wall portion 7a, a plurality of pressure adjusting holes 7e are formed on the same circumference (corresponding to a first through portion). A pressure chamber 13 is formed by a space closed by the disc portion 6b, the bottom wall portion 7a, and the side wall portion 7b.

  A concave portion 7c1 is formed in the protruding portion 7c from the inlet IN side toward the outside of the engine block EB, and a part of the control member 10 is accommodated in the concave portion 7c1. On the inner periphery of the recess 7c1, a holding guide 7d for restricting the swing of the control member 10 is formed so as to protrude toward the inner periphery. In other words, a space (groove) is secured between the outer periphery of the control member 10 and the recess 7c1 by the holding guide 7d. Thereby, the recess 7c1 and the suction port IN side can always communicate with each other, and the pressure relief in the recess 7c1 due to the operation of the movable member 7 is ensured.

  The end of the projecting portion 7c is always inserted a predetermined length or more into the accommodation chamber 8 from the inlet IN side. A seal member 11 is provided on the outer periphery of the end of the protruding portion 7c so as to be in sliding contact with the inner peripheral surface 6a2 of the storage chamber 8 with a predetermined elastic force. By permitting the sliding contact of the seal member 11 or the flow of minute cooling water, a damper function that suppresses the vibrational movement of the movable member 7 in the axial direction is exhibited.

  A storage chamber 8 is formed in the drive shaft 6a (corresponding to a hollow drive shaft). A coil spring 9 as an urging member and a spring guide 12 extending in the axial direction on the inner periphery of the coil spring 9 are housed in the storage chamber 8. Even if the diameter of the coil spring 9 is increased by the action of the centrifugal force due to the rotation drive, the diameter of the coil spring 9 is suppressed from coming into contact with the inner wall 6a2 of the storage chamber 8, and the characteristics of the coil spring 9 are stabilized. Plan.

  The outer end of the engine block of the coil spring 9 is held by a spring guide 12, while the end of the coil spring 9 on the inlet IN side is in contact with the bottom surface of the inserted protrusion 7c. Thereby, the movable member 7 is urged toward the suction port IN, in other words, in a direction in which the discharge amount of the water pump WP decreases.

  The spring guide 12 is formed with an orifice hole 12a that communicates the inside of the housing chamber 8 with the outside of the engine block EB. The orifice hole 12a is connected to the communication hole 6a11. When the movable member 7 moves in the axial direction, and the protrusion 7c moves in the axial direction along with this movement, the amount of air discharged or sucked in the storage chamber 8 is adjusted by the orifice hole 12a. Thereby, the damper function with respect to the action | operation of the movable member 7 is exhibited.

  The control member 10 has a heat transfer housing formed of a material having high thermal conductivity (for example, a copper alloy or an aluminum alloy). The heat transfer housing is fixed to the distal end of the fixed portion 6e, and has a distal end portion 10a that accommodates the thermowax, and a small-diameter cylinder portion 10b that extends from the distal end portion 10a to the outside of the engine block. A piston pin 10c that presses the movable member 7 is inserted into the cylinder portion 10b. Thermowax is a liquid or gel material whose volume changes in response to temperature.

  When the temperature of the cooling water is high, the heat of the cooling water is transferred to the thermo wax in the accommodation chamber via the heat transfer housing. This heat transfer causes the thermal wax to expand in volume, pushing the piston pin 10c against the biasing force of the coil spring 9. On the other hand, when the temperature decreases, the heat of the thermowax is released to the cooling water through the heat transfer housing. Due to this heat release, the volume of the thermo wax is contracted, and the force for pushing the piston pin 10c is reduced and pushed back by the coil spring 9.

  Next, the driving action of the water pump based on the above configuration will be described. When the rotational driving force is transmitted to the pulley 4, the rotational driving force rotationally drives the impeller 6 and the movable member 7 via the plate member 4c and the drive shaft 6a. Basically, this rotational driving force is determined by the driving state of the engine. The blade 6c pushes the cooling water in the vicinity of the rotating shaft to the outer peripheral side.

  The cooling water in the pressure chamber 13 is discharged to the discharge port OUT through a minute gap between the groove 7f and the blade 6c by the centrifugal force accompanying the rotation of the impeller 6 and the movable member 7. On the other hand, the cooling water supplied from the inlet port IN side is introduced into the pressure chamber 13 through the pressure adjusting hole 6d and the pressure adjusting hole 7e.

  When a pressure difference is generated between the pressure chamber 13 and the suction port IN side of the movable member 7, the movable member 7 receives thrust in the direction of the rotation axis. Specifically, when the flow rate of the cooling water discharged from the pressure chamber 13 is smaller than the flow rate flowing in from the pressure adjusting holes 6d and 7e, the pressure on the suction port IN side becomes smaller than the pressure in the pressure chamber 13. Then, a thrust is generated on the movable member 7 on the suction port IN side. On the other hand, if the flow rate of the cooling water discharged from the pressure chamber 13 is larger than the flow rate flowing from the pressure adjusting holes 6d and 7e, the pressure in the pressure chamber 13 becomes smaller than the suction port IN side, and the movable member 7 has Thrust is generated in the direction outside the engine block.

  By appropriately adjusting the shape of the pressure adjusting holes 6d and 7e, the urging force of the coil spring 9, and the temperature characteristics of the control member 10, the thrust received by the movable member 7 is controlled to determine the position of the movable member 7 in the rotational axis direction. . Thus, the flow rate is changed by changing the height at which the blade portion 6c of the impeller 6 protrudes and protrudes from the movable member 7, and the impeller 6 functions as a variable displacement pump.

  Next, the operation characteristics of the water pump of Example 1 will be described. FIG. 4 is a characteristic diagram showing the relationship between the discharge flow rate and the engine speed. The horizontal axis represents the engine speed, and the vertical axis represents the discharge flow rate of the water pump WP. Hereinafter, the axial length of the blade 6 c when the blade 6 c is exposed to the suction port IN side of the movable member 7 is referred to as “blade height”.

  The line A in FIG. 4 shows the case where the movable member 7 moves most outward in the axial direction engine block EB and the blade 6c is most exposed to the inlet IN side of the movable member 7 (hereinafter referred to as blade height Max). The characteristic in is shown. Line B in FIG. 4 maintains the state in which the movable member 7 moves most to the axial suction port IN side and is not exposed at all to the suction port IN side of the movable member 7 of the blade 6c (hereinafter referred to as blade height Min). The characteristic in the case where it did is shown. The higher the blade height, the larger the discharge flow rate with respect to the engine speed, and the lower the blade height, the smaller the discharge flow rate with respect to the engine speed.

  4 is a characteristic achieved by the position of the movable member 7 shown in the sectional view of FIG. 8, and the characteristic shown in the line B of FIG. 4 is the movable member 7 shown in the sectional view of FIG. 4 is a characteristic achieved by the position of the movable member 7 shown in the cross-sectional view of FIG. 7. The characteristic shown in the middle of the region C between the line A and the line B in FIG. .

  FIG. 5 is a characteristic diagram showing the relationship between the water temperature and the force acting on the piston pin. The horizontal axis represents the temperature of the cooling water flowing through the engine, and the vertical axis represents the force acting on the piston pin 10c by the thermo wax. As the water temperature increases, the thermowax expands and the force acting on the piston pin 10c increases.

  Now, when the water temperature is low, it is necessary to reduce the discharge flow rate in order to promote warm-up of the engine. On the other hand, when the water temperature is high, it is necessary to increase the discharge flow rate to promote engine cooling. At the same time, the discharge flow rate is closely related to the pump load, and reducing the pump load leads to an improvement in fuel consumption.

  Therefore, the control member 10 automatically controls the axial position of the movable member 7 according to the temperature of the cooling water, and the region C sandwiched between the lines A and B in FIG. The optimum characteristics can be selected appropriately.

  Furthermore, a desired characteristic may be set independently of the control member 10 by adjusting the position / size / biasing member of the pressure adjusting holes 6d, 7e. FIG. 6 shows the characteristic that the pressure in the pressure chamber 13 is rapidly lowered at a predetermined engine speed or higher. When the engine speed corresponding to the point E on the characteristic B is reached, the flow rate of the cooling water discharged from the pressure chamber 13 is configured to be smaller than the flow rate flowing from the pressure adjusting holes 6d and 7e. That is, a minimum required discharge flow rate is set when the engine speed is high, and an optimum characteristic can be selected as appropriate in a region D sandwiched between the characteristics.

  As a result, thrust is generated in the movable member 7 in the direction toward the outside of the engine block EB, and in a region where the engine speed is equal to or higher than the predetermined speed, the blade 6c is always exposed to some extent, that is, a predetermined blade height is ensured. Then, in a region where the engine speed is high, in addition to the discharge flow rate control by the control member 10, a minimum discharge flow rate can be secured, and stable cooling performance can be secured.

As described above, Example 1 has the following effects.
(1) A hollow drive shaft 6a to which a rotational force is transmitted, an impeller 6 having a plurality of blades 6c fixed to the drive shaft 6a and extending in the direction of the rotation shaft, and a rotation shaft direction of the drive shaft 6a A plurality of side walls 7b that are movably provided and surround the outer peripheral side of the impeller 6 and a bottom wall 7a that is provided on the blade forming surface side of the impeller 6 and each of the blades 6c can protrude and retract on the bottom wall 7a A movable member 7 having a groove 7f formed therein, an impeller 6 and the movable member 7 accommodated therein, a suction portion provided on the center side of the rotation shaft, and a pump chamber 14 having a discharge portion provided on the outer peripheral side; A coil spring 9 provided in the drive shaft 6a for biasing the movable member 7 to one side in the rotational axis direction, and a control member 10 for moving the movable member 7 in the rotational axis direction against the coil spring 9, Equipped with.

  Therefore, since a biasing member such as a coil spring is not disposed in the fluid flow path, the resistance of the fluid can be reduced as much as possible.

  (2) Since the urging member is the coil spring 9 arranged in the direction of the rotation axis of the drive shaft 6a, it can be easily inserted into the drive shaft 6a.

  (3) The coil spring 9 is configured to come into contact with the inner peripheral surface 6a2 of the drive shaft 6a when the drive shaft 6a rotates at a high speed. Therefore, while functioning as a guide at the time of the stroke of the coil spring 9, the diameter expansion by the action of the centrifugal force can be suppressed, and a stable stroke characteristic can be obtained.

  (4) A spring guide 12 extending in the direction of the rotation axis is provided on the inner periphery of the coil spring 9. Therefore, the coil spring 9 can be prevented from falling down.

  (5) A part of the movable member 7 is inserted into the accommodation chamber 8 in which the coil spring 9 in the drive shaft 6a is accommodated, and a damper action is performed when the movable member 7 moves. Do. Thereby, the vibration of the movable member 7 etc. can be suppressed.

  (6) An elastic seal member 11 is provided between the storage chamber 8 and a part of the movable member 7 inserted from one end opening side, and a damper action is performed by the elastic force of the seal member 11. Thereby, the vibration of the movable member 7 etc. can be suppressed.

  (7) Air (or fluid) is introduced into the storage chamber 8, and when a part of the movable member 7 is inserted into the storage chamber 8, the air (or fluid) in the storage chamber 8 is exposed to the outside. Damper action is performed by the diaphragm that enters and exits. Thereby, the vibration of the movable member 7 etc. can be suppressed.

  (8) The control member 10 is provided in a state where at least a part thereof is inserted into the recess 7c1 provided at the rotation center of the impeller 6 and the movable member 7. Therefore, the amount of protrusion by which the control member 10 protrudes from the movable member 7 toward the suction portion can be reduced, and the flow path resistance from the suction portion to the discharge portion can be reduced.

  (9) At the center of the rotating shaft of the movable member 7, there is provided a protrusion 7c that is inserted into the storage chamber 8 in which the urging member 9 of the drive shaft 6a is stored, and the protrusion 7c is attached by the coil spring 9. Be forced. Therefore, it is possible to contact the coil spring 9 on the outer side of the engine block of the recess 7c1, that is, the back side when viewed from the suction portion, and it is possible to suppress the protrusion of the member to the suction portion side.

  (10) The fixed portion 6e is extended in the axial direction from the inner peripheral side of the impeller 6 with respect to the blade 6c, and the insertion portion 7g is formed through the portion of the movable member 7 corresponding to the fixed portion 6e. The one end side in the axial direction of the control member 10 is fixed to the fixing portion 6e, and the other end side in the axial direction presses the bottom of the recess 7c1 provided in the protruding portion 7c in the direction of the rotation axis. Therefore, the amount of protrusion by which the control member 10 protrudes from the movable member 7 toward the suction portion can be reduced, and the flow path resistance from the suction portion to the discharge portion can be reduced.

  (11) The swing of the control member 10 is restricted by a plurality of holding guides 7d provided in the circumferential direction on the inner periphery of the recess 7c1. Therefore, a pressure relief passage in the pressure chamber 13 can be secured to obtain a smooth operation, and vibration of the control member 10 can be suppressed.

  (12) The control member 10 is a thermo element that expands and contracts in response to temperature. Therefore, the position of the movable member 7 can be controlled according to the coolant temperature.

  (13) The control member 10 is a thermo wax interposed between members that are relatively movable in the axial direction. Therefore, control according to the water temperature can be realized with a small number of parts.

  (14) The bottom wall of the movable member 7 is provided with a pressure adjusting hole 7e (first through portion) penetrating in the rotation axis direction at a position different from the groove 7f. Therefore, the negative pressure generated in the pressure chamber 13 can be suppressed.

  (15) The impeller 6 is provided with a pressure adjusting hole 6d (second penetrating portion) penetrating in the rotation axis direction. Therefore, the negative pressure generated in the pressure chamber 13 can be suppressed.

  (16) A drive shaft 6a to which a rotational force is transmitted and provided with an accommodating portion (accommodating chamber 8) therein, and a pump structure (water pump) that discharges fluid from the rotation center portion to the outer peripheral side by the rotation of the drive shaft 6a WP), a movable member 7 which is provided so as to be movable in the rotational axis direction of the drive shaft 6a, and changes the discharge amount of the pump constituent body by moving in the axial direction, and a housing portion (housing chamber 8) of the drive shaft 6a And an urging member (coil spring 9) for urging the movable member 7 in a direction in which the discharge amount of the pump structure decreases, and the control member 10 is moved in the direction of the rotation axis against the urging member. And a control member. Therefore, since a biasing member such as a coil spring is not disposed in the fluid flow path, the resistance of the fluid can be reduced as much as possible.

  Next, Example 2 will be described. FIG. 9 is a cross-sectional view illustrating the configuration of the second embodiment. Since the basic configuration is the same as that of the first embodiment, only different points will be described. In the first embodiment, the control member 10 includes the piston pin 10c as a separate member. On the other hand, in Example 2, the piston pin part 7d is extended from the protrusion part 7c of the movable member 7, and the point which shape | molded integrally differs. As a result, the number of parts can be reduced and the number of assembling steps can be reduced.

  Next, Example 3 will be described. FIG. 10 is a cross-sectional view illustrating the configuration of the third embodiment. Since the basic configuration is the same as that of the first embodiment, only different points will be described. In the first embodiment, the pulley 4 is supported on the outer periphery of the supporting cylindrical portion 1 d of the housing 1 via the bearing 2. On the other hand, in the third embodiment, the drive shaft 6a is supported on the inner periphery of the supporting cylindrical portion 1d via the two bearings 20 and 30, and the pulley 40 is supported by the drive shaft 6a. Different.

  The pulley 40 is a bottomed cylindrical member, and is connected to the drive shaft 6a at the rotation center of the plate portion 42, a cylindrical portion 41 around which the drive belt is stretched, a plate portion 42 that closes the outside of the engine block of the cylindrical portion 41. A cylindrical connecting portion 43 formed therethrough. The drive shaft 6a and the connecting portion 43 are press-fitted and fixed.

  In the third embodiment, the radial force acting on the pulley 40 by the drive belt is transmitted from the drive shaft 6 a to the housing 1 through the bearings 20 and 30. Therefore, in the third embodiment, the connecting end portion 6a10 is extended with the same diameter without reducing the diameter as in the first embodiment to ensure the strength. In this case, the bearing 20 can have a smaller diameter than the bearing 2 of the first embodiment, and the weight can be reduced. In addition, since it is supported by two bearings 20 and 30 that are spaced apart in the direction of the rotation axis, an inexpensive point contact type such as a ball bearing can be used.

  Next, Example 4 will be described. FIG. 11 is a cross-sectional view illustrating a configuration of the fourth embodiment. Since the basic configuration is the same as that of the third embodiment, only different points will be described. The third embodiment is different in that the bearing 21 that supports the drive shaft 6a is a line contact type needle bearing. The end of the bearing 21 on the suction port IN side extends from the end of the cylindrical portion 41 to the suction port IN side. Thus, by using a line contact type, a wide support range can be obtained, and more stable support of the drive shaft 6a can be achieved.

  Next, Example 5 will be described. FIG. 12 is a cross-sectional view illustrating a configuration of the fifth embodiment. Since the basic configuration is the same as that of the first embodiment, only different points will be described. The fifth embodiment is different from the first embodiment in that the control member is not a thermowax, but a solenoid 101, an armature 102, and a coil spring 9 that urges the armature 102 toward the suction port IN. Is different. A current is passed through the solenoid 101 to generate a magnetic field, and the axial position of the movable member 7 is controlled by the balance between the urging force of the coil spring 9 acting on the armature 102 and the electromagnetic force.

  The protrusion 7c extends from the bottom wall 7a toward the outside of the engine block. In other words, the recess is not formed, and is formed so as not to protrude from the bottom wall portion 7a to the inlet IN side. Thereby, the flow path resistance is further reduced.

  A connecting pin 103 is connected to the protruding portion 7c. The connecting pin 103 is accommodated in the accommodating chamber 8, and an armature 102 having the same diameter as that of the accommodating chamber 8 is fixed thereto. A coil spring 9 is disposed outside the engine block of the armature 102, and urges the armature 102 toward the inlet port IN. A solenoid 101 is attached to the inner periphery of the supporting cylindrical portion 1d.

  In the fifth embodiment, the solenoid 101 and the armature 102 are positioned so that the axial positions do not overlap when the power is not supplied. However, the storage chamber 8 is further expanded to the outside of the engine block, and the axial direction even in the initial state. The magnetic paths may be formed more efficiently by arranging them at overlapping positions.

  By configuring the control member with the solenoid 101, it is possible to cope with various control states and further improve fuel consumption and the like. Further, since the movable member 7 is moved by the suction force rather than the pressing force, the control member can be disposed without protruding from the movable member 7 toward the suction port IN. Therefore, the channel resistance can be effectively suppressed.

  Each example has been described above. However, the present invention is not limited to the above-described configuration, and the scope of the claims includes the following. In the first embodiment, the orifice hole 12a and the communication hole 6a11 are connected to the atmosphere. However, an orifice hole connected to the flow path of the cooling water such as the suction port IN and the discharge port OUT is formed, and discharged along with the movement of the cooling water. It is good also as a structure which adjusts quantity and inhalation amount.

  Although a configuration using a thermowax or a solenoid as the control member has been shown, an axial center oil passage or the like may be formed around the rotation shaft, and the position of the movable member 7 may be controlled by hydraulic pressure or the like.

  Although the example which shape | molded the drive shaft 6a and the impeller 6 with the resin material was shown, you may shape | mold with a metal material (aluminum etc.).

  In the first embodiment, the supporting cylindrical portion 1d has a smaller diameter than the outer periphery of the housing cylindrical portion 1a, but may have a larger diameter. Further, the small diameter cylindrical portion 4 a of the pulley 4 may have the largest diameter in the pulley 4.

  Although the flange part 4b was formed in the edge part of the pulley 4, you may form in other than an edge part. Moreover, although the diameter of the flange portion 4b is larger than that of the small diameter cylindrical portion 4a, the diameter may be the same as or smaller than the small diameter cylindrical portion 4a without expanding the diameter. Furthermore, although the drive shaft 6a and the plate member 4c are connected and fixed by the bolt 4e, they may be connected and fixed by press-fitting. Further, although the connecting portion 4c1 extends to a position where it overlaps with the supporting cylindrical portion 1d in the axial position, it may not be overlapped.

  In fixing the control member 10 to the fixing portion 6e, the female screw is employed in the first embodiment, but it may be fixed by press-fitting or caulking.

It is sectional drawing of the water pump of Example 1. FIG. It is a disassembled perspective view of the water pump of Example 1. FIG. It is the axial front view of the movable member of Example 1, and the partial sectional view in the blade | wing of a movable member. It is a characteristic view showing the relationship of the discharge flow volume with respect to the engine speed of Example 1. FIG. It is a characteristic view showing the relationship between the water temperature of Example 1, and the force which acts on a piston pin. It is a characteristic view which shows the characteristic which reduces the pressure in a pressure chamber rapidly more than the predetermined engine speed of Example 1. FIG. It is sectional drawing of the water pump of Example 1. FIG. It is sectional drawing of the water pump of Example 1. FIG. It is sectional drawing showing the structure of the water pump of Example 2. FIG. 6 is a cross-sectional view illustrating a configuration of a water pump according to Embodiment 3. FIG. 10 is a cross-sectional view illustrating a configuration of a water pump according to Example 4. FIG. FIG. 10 is a cross-sectional view illustrating a configuration of a water pump according to a fifth embodiment.

Explanation of symbols

EB engine block
IN inlet
OUT outlet
WP Water pump 1 Housing 4 Pulley 6 Impeller 6a Drive shaft 6c Blades 6d, 7e Pressure adjusting hole 6e Fixed part
7c1 Concave part 7 Movable member 7a Bottom wall part 7b Side wall part 7c Projection part 7d Holding guide 7d Piston pin part 7f Groove 8 Housing chamber 9 Coil spring 10 Control member 11 Seal member
12a Orifice hole 12 Spring guide 13 Pressure chamber 14 Pump chamber

Claims (16)

A hollow drive shaft through which rotational force is transmitted;
An impeller having a plurality of blades fixed to the drive shaft and extending in the direction of the rotation axis;
A side wall provided so as to be movable in the direction of the rotation axis of the drive shaft, and surrounding an outer peripheral side of the impeller;
A movable member having a bottom wall provided on the blade forming surface side of the impeller, and having a plurality of grooves in which the blades can protrude and retract on the bottom wall;
A pump chamber that houses the impeller and the movable member therein, and has a suction portion provided on the rotation shaft center side, and a discharge portion provided on the outer peripheral side;
An urging member provided in the drive shaft and urging the movable member toward one side in the direction of the rotation axis;
A control member that moves the movable member in the rotation axis direction against the biasing member;
A variable displacement fluid pump characterized by comprising: The variable displacement fluid pump of claim 1,
The variable displacement fluid pump according to claim 1, wherein the biasing member is a coil spring disposed in a direction of a rotation axis of the drive shaft. The variable displacement fluid pump according to claim 2,
The variable capacity fluid pump according to claim 1, wherein the coil spring is configured to contact an inner peripheral surface of the drive shaft when the drive shaft is rotated at a high speed. The variable displacement fluid pump according to claim 2,
A variable displacement fluid pump according to claim 1, wherein a spring guide extending in the direction of the rotation axis is provided on an inner periphery of the coil spring. The variable displacement fluid pump of claim 1,
The housing chamber in which the biasing member of the drive shaft is housed is configured such that a part of the movable member is inserted from one end opening side, and performs a damper action when the movable member moves. Features variable displacement fluid pump. The variable displacement fluid pump of claim 1,
A variable capacity characterized in that an elastic seal member is provided between the storage chamber and a part of the movable member inserted from one end opening side, and a damper action is performed by an elastic force of the seal member. Fluid pump. The variable displacement fluid pump of claim 1,
Air or fluid is introduced into the storage chamber, and when a part of the movable member is inserted into the storage chamber, a damper action is performed by a throttle that allows the air or fluid in the storage chamber to enter and exit the outside. A variable displacement fluid pump characterized by The variable displacement fluid pump of claim 1,
The variable displacement fluid pump according to claim 1, wherein the control member is provided in a state in which at least a part thereof is inserted into a recess provided at a rotation center of the impeller and the movable member. The variable displacement fluid pump of claim 1,
At the center of the rotating shaft of the movable member, a protrusion is provided that is inserted into a storage chamber in which the biasing member of the drive shaft is stored.
The variable displacement fluid pump, wherein the protrusion is biased by the biasing member. The variable displacement fluid pump of claim 9,
While extending the fixing portion in the axial direction from the inner peripheral side than the blades in the impeller,
Forming an insertion portion in a portion corresponding to the fixed portion in the movable member, inserting the fixed portion,
One end of the control member in the axial direction is fixed to the fixed portion, and the other end in the axial direction presses the bottom of a recess provided in the protruding portion toward the rotation axis. The variable displacement fluid pump of claim 10, wherein
The control member is controlled to swing by a plurality of holding guides provided in a circumferential direction on the inner periphery of the recess. The variable displacement fluid pump of claim 8,
The variable displacement fluid pump, wherein the control member is a thermo element that expands and contracts in response to temperature. The variable displacement fluid pump of claim 12,
The variable displacement fluid pump according to claim 1, wherein the control member is a thermo wax interposed between members that are relatively movable in the axial direction. The variable displacement fluid pump of claim 1,
The variable capacity fluid pump according to claim 1, wherein a first penetrating portion penetrating in a rotation axis direction at a position different from the groove is provided on a bottom wall of the movable member. The variable displacement fluid pump of claim 1,
The variable displacement fluid pump according to claim 1, wherein the impeller is provided with a second penetrating portion penetrating in the rotation axis direction. A driving shaft to which a rotational force is transmitted and a housing portion is provided inside;
A pump structure that discharges fluid from the center of rotation to the outer peripheral side by rotation of the drive shaft;
A movable member provided so as to be movable in the rotational axis direction of the drive shaft, and changing the discharge amount of the pump component by moving in the axial direction;
An urging member that is provided in the housing portion of the drive shaft and urges the movable member in a direction in which the discharge amount of the pump component decreases;
A control member that moves the control member in the direction of the rotation axis against the biasing member;
A variable displacement fluid pump characterized by comprising:

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