JP2008280936A - Oil pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil pump capable of reducing noise generated by vibration thereof without enlargement of the pump. <P>SOLUTION: In the oil pump 1 provided with a drive shaft 4 having a bearing storage part 12 storing a first bearing 13a therein projectingly provided at axial direction one end part of a housing body 2 and having the axial direction one end part provided to project to an outside from the bearing storage part 12 side, a pulley 5 provided at the axial direction one end side of the drive shaft 4, a spindle member 11 for damping pump vibration fixed on the housing body 2, a space which is normally a dead space is effectively utilized by providing the spindle member 11 at an outer circumference side space part of the bearing storage part 12 formed in a part in the axial direction between the housing body 2 and the pulley 5, and vibration control effect at a time of vibration of the pump 1 is improved without enlargement of the oil pump 1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an improvement of an oil pump used as a drive source for a continuously variable transmission or a power steering device of a vehicle, and more particularly to an oil pump capable of reducing noise generated due to vibration of the oil pump.

  Recently, in vehicles such as automobiles, oil pumps such as gear pumps and vane pumps are used as drive sources for continuously variable transmissions, power steering devices, and the like. Vibration is generated, and noise is generated along with the vibration. And when this noise becomes excessive, since there exists a possibility of giving a passenger discomfort, various techniques for suppressing this noise are provided. As an example thereof, for example, one described in Patent Document 1 below is known.

  Briefly, this oil pump is a so-called vane pump used in a power steering apparatus of an automobile, and has a substantially bottomed cylindrical housing body having a pump housing chamber therein, and an opening of the housing body. A cover member that is closed, bearings that are housed in bearing housing portions that are recessed in the inner bottom surface of the housing body and the inner surface of the cover member, and are rotatably supported by the bearings in the axial direction. A drive shaft having one end projecting outward from the bottom of the housing main body, a pulley provided at one end of the drive shaft, transmitting a driving force of the engine to the drive shaft, and housed in the pump housing chamber; And a pump element that is rotationally driven by a drive shaft.

  On the outer surface of the cover member, a damper accommodating portion having a substantially C-shaped cross section is formed in the outer peripheral area of the bearing accommodating portion so as to surround the bearing accommodating portion. A weight member having an outer shape slightly smaller than the damper accommodating portion is accommodated in a loosely fitted state. And this damper accommodating part is sealed by the plate-shaped plate member fixed to the outer surface of a cover member with a volt | bolt, and, thereby, the damping device is comprised.

In the vibration damping device, when the oil pump vibrates, the weight member moves in the damper accommodating portion due to the vibration of the oil pump, and the weight member, the damper accommodating portion, The vibration is attenuated by energy loss due to collision or sliding friction generated between the weight member and the weight member and the plate member.
JP 2002-161865 A

  Recently, various devices are mounted on vehicles, so there is a demand for miniaturization of oil pumps, and designers are designing to fit the oil pump in a limited space. .

  However, the vibration of the oil pump as described above can be confirmed only by actually operating the pump, and the size of the weight member is determined according to the magnitude of the vibration.

  Then, depending on the magnitude of the vibration, the oil pump may be larger than the dimensions at the time of design, which may deteriorate the mountability of the oil pump on the vehicle.

  In particular, in the conventional oil pump, since the weight member is accommodated on the outer surface of the cover member, the cover member is formed more compact than usual to accommodate the weight member. As a result, there is a problem that the size of the oil pump in the axial direction increases more remarkably.

  The present invention has been devised in view of the technical problem of the conventional oil pump, and it is an object of the present invention to provide an oil pump that can reduce noise caused by vibration without increasing the size of the pump. .

  The invention according to claim 1 is provided with a housing main body having a pump housing chamber therein, and provided at one end of the housing main body in the axial direction so as to protrude along the axial direction, and has an outer shape smaller than that of the housing main body. A bearing housing portion that houses the bearing therein, a drive shaft that is rotatably supported by the bearing, and that is disposed so that at least one axial end side projects outward from the bearing housing portion side, and the pump housing A pump element housed in a room and driven to rotate by the drive shaft to suck and discharge oil; and a power transmission member provided at one end of the drive shaft and transmitting a drive force to the drive shaft. A weight member fixed to the housing main body is provided on the outer peripheral side of the bearing housing portion, and a notch portion that is externally fitted to the bearing housing portion is provided in the weight member. That.

  According to this invention, the mass of the housing main body is increased by fixing the weight member to the housing main body which is an oscillation source, thereby changing the natural frequency of the housing main body. By changing the natural frequency of the housing body, the resonance point with the other oscillation source can be shifted, thereby suppressing the amplification of the vibration of the entire oil pump due to the resonance with the other oscillation source. Can do.

  In particular, in the present invention, by arranging the weight member in a space that is normally a dead space between the housing body and the power transmission member, the space of the oil pump can be effectively utilized. As a result, the effect of preventing vibration and noise can be obtained without increasing the size of the oil pump.

  Further, since the weight member is provided with the cutout portion that can be fitted into the bearing housing portion, the weight member can be easily assembled as compared with a case where the weight member is fitted into the bearing housing portion from the axial direction. Is possible. As a result, the assembling workability of the oil pump can be improved, and the manufacturing cost can be reduced.

  The invention according to claim 2 is the one in which the invention according to claim 1 is applied to a so-called vane pump, and the present invention can achieve the same effects as the invention according to claim 1. .

  In the variable displacement type oil pump such as the vane pump, the vibration of the pump due to pulsation or the like is more noticeable than in the fixed displacement type oil pump. Act on.

  According to a third aspect of the present invention, the notch is formed in an opening corresponding to the region corresponding to the discharge port, and the weight member surrounds the region corresponding to the suction port with respect to the bearing housing portion. It is characterized by providing as follows.

  In the variable displacement type oil pump such as the vane pump described above, since the internal pressure is not balanced, the drive shaft is pressed to the suction port side by the pump discharge pressure, and this pressure force slightly increases the same direction. Will cause a misalignment. In this case, the cam profile in the pump changes due to the deviation of the axis of the drive shaft to cause pulsation, and this pulsation causes vibration of the apparatus.

  Therefore, according to the present invention, by arranging the weight member on the region corresponding to the suction port, the deformation of the drive shaft due to the pump discharge pressure as described above can be effectively suppressed, and the deformation It is possible to prevent the drive shaft from being misaligned. As a result, the cam profile can be prevented from changing due to the axial misalignment of the drive shaft, and the accompanying pump pulsation can be suppressed, so that the occurrence of vibration due to the pulsation can be reduced.

  According to a fourth aspect of the present invention, the housing body is formed of an aluminum alloy material, while the weight member is formed of an iron-based material, and a predetermined gap is provided between the weight member and the bearing housing portion. It is characterized by that.

  According to the present invention, when the pump generates heat, the bearing housing portion expands more than the weight member due to the difference between the linear expansion coefficients of each other. Since the gap is provided, a difference in the expansion amount of the bearing housing portion with respect to the expansion amount of the weight member can be absorbed by the gap. For this reason, the thermal expansion of a bearing accommodating part is restrained by the said weight member, and there is no possibility that an internal stress will arise in this bearing accommodating part.

  In addition, since the gap is provided, there is no possibility that the weight member interferes with the bearing housing portion when the oil pump vibrates, so that generation of noise due to such interference can be prevented.

  The invention according to claim 5 is characterized in that a second weight member is provided facing the notch portion side of the weight member.

  According to the present invention, it is possible to increase the mass of the entire weight member by providing the second weight member, thereby further improving the noise prevention effect. And since this 2nd weight member is provided facing the notch part side of the said weight member, the mass of the whole weight member can be increased without accompanying the enlargement to the axial direction of an oil pump especially.

  The invention described in claim 6 is characterized in that a recess is formed in an axial end of the power transmission member on the housing body side, and at least a part of the weight member is accommodated in the recess.

  According to the present invention, since at least a part of the weight member is accommodated in the recess, the volume of the space in the recess can be reduced, and resonance during oil pump vibration caused by the space is reduced. be able to. As a result, noise based on the resonance action is reduced, and the noise generated when the oil pump vibrates is reduced.

  The invention according to claim 7 is characterized in that the weight member is integrally and fastened to the housing main body together with a bracket for mounting a vehicle body by a common bolt.

  According to the present invention, since the housing body, the bracket that supports the housing body on the vehicle body, and the weight member are integrally coupled, the bracket serves to improve the rigidity of the housing body. Vibration is suppressed more effectively.

  The invention described in claim 8 is characterized in that the weight member is fixed to the housing body by a plurality of bolts.

  According to the present invention, since the weight member is fixed to the housing body via the plurality of bolts, the coupling force between the two is enhanced, so that when the oil pump is vibrated, both are vibrated integrally. Is possible. Thereby, generation | occurrence | production of the noise by the said weight member and a housing main body interfering with each other can be suppressed.

  The invention according to claim 9 is characterized in that the weight member is attached only to the housing body.

  According to the present invention, since the weight member is attached only to the housing body, the apparatus can be delivered or sold with the weight member assembled to the housing body.

  Hereinafter, embodiments of an oil pump according to the present invention will be described in detail with reference to the drawings. In the present embodiment, the oil pump is applied to a vane pump used in a power steering device of an automobile as in the conventional case.

  1 to 6 show a first embodiment of the present invention. As shown in FIGS. 1, 5 and 6, the oil pump 1 is formed of an aluminum alloy material in a substantially bottomed cylindrical shape, A housing body 2 having a pump housing chamber 2a therein, a rear cover 3 that closes an opening of the housing body 2, and first and second bearings 13a and 13b accommodated in the housing body 2 and the rear cover 3 The drive shaft 4 is supported so as to be rotatable, and has one axial end projecting from the bottom 2b side of the housing body 2 to the outside, and fixed to the one axial end of the drive shaft 4 so as not to be relatively rotatable. A pulley 5 as a power transmission member for transmitting the driving force of the engine (not shown) to the drive shaft 4, a substantially annular adapter ring 6 fitted and fixed to the peripheral wall of the pump housing chamber 2a, and the adapter. An annular cam ring 8 that is housed and arranged on the inner peripheral side of the tulling 6 and that can swing freely around the swing fulcrum pin 7 in the left-right direction in FIG. A rotor 9 that is connected to the drive shaft 4 so as not to rotate relative to the drive shaft 4 and is fitted into and fixed to the peripheral wall of the pump housing chamber 2a, and is sandwiched between the bottom 2b of the housing body 2 and the adapter ring 6. The pressure plate 10 and a weight member 11 integrally fixed to the housing main body 2 by two bolts 14 and 14 are provided.

  As shown in FIG. 5, one end portion in the axial direction on the bottom 2b side of the housing body 2 is formed so as to protrude in a stepped diameter direction along the axial direction, and the first bearing 13a is accommodated on the inner peripheral side thereof. A bearing housing portion 12 is provided. That is, the bearing housing portion 12 is provided with a first bearing housing hole 12a that opens to one end side in the axial direction, and the first bearing 13a is inserted into the first bearing housing hole 12a. The first bearing 13a is prevented from falling off by a snap ring fitted in an annular groove formed near the opening edge of the first bearing receiving hole 12a.

  On the other hand, the inner surface 3a of the cover member 3 is also formed with a second bearing receiving hole 3b into which the second bearing 13b is fitted and inserted at a substantially central position, and the second bearing receiving hole 3b is accommodated in the second bearing receiving hole 3b. The other end in the axial direction of the drive shaft 4 is rotatably supported by the two bearings 13b.

  As shown in FIG. 1 and FIG. 2, the pulley 5 is formed in a substantially bottomed cylindrical shape, and an accommodation space S that is a recess set to a predetermined inner diameter (inner peripheral radius) r1 is formed on the inner peripheral side thereof. And is attached to the drive shaft 4 so that the open end surface 5a faces the outer bottom surface 2c of the housing body 2. In addition, the bottom portion 5b of the pulley 5 is formed with through-out portions not shown in the drawing at a plurality of locations along the circumferential direction. A belt linked to a crankshaft (not shown) that outputs the driving force of the engine is wound around the pulley 5, and the driving force of the engine is transmitted to the drive shaft 4 through the belt.

  As shown in FIG. 5, the cam ring 8 is arranged in the pump housing chamber 2 a in an eccentric state with respect to the rotor 9, and a predetermined space is formed between the adapter ring 6 and the radial direction. ing. The space is divided into two pressure chambers, a first fluid pressure chamber P1 and a second fluid pressure chamber P2, by the swing fulcrum pin 7 and a seal member 15 disposed substantially in a point symmetrical position with the swing fulcrum pin 7. ing.

  The rotor 9 has a substantially disk shape, and rotates in the arrow direction (counterclockwise direction) in FIG. 6 when the drive shaft 4 is rotationally driven. The outer periphery of the rotor 9 has a plurality of slots 9a that are radially cut out at equally spaced positions in the circumferential direction. In these slots 9 a, rectangular plate-like vanes 16 are respectively held so as to be able to protrude and retract in the direction of the inner peripheral surface of the cam ring 8.

  In the space formed between the cam ring 8 and the rotor 9 in the radial direction, a plurality of pump chambers 17 are formed by two adjacent vanes 16, 16 to swing the cam ring 8. Accordingly, the volume of each pump chamber 17 is increased or decreased. The cam ring 8 is always urged toward the first fluid pressure chamber P1 by a compression coil spring disposed in the second fluid pressure chamber P2.

  Further, as shown in FIGS. 5 and 6, the inner surface 3 a of the rear cover 3 is substantially within a range corresponding to the suction area A in which the volume of each pump chamber 17 gradually increases as the rotor 9 rotates. A suction port 18 having an arc shape is formed. The suction port 18 supplies oil sucked from a reservoir tank (not shown) into the pump chambers 17 through a suction passage 19 formed in the rear cover 3.

  On the other hand, on the inner surface 10a of the pressure plate 10 on the rotor 9 side, as shown in FIG. 5, the range corresponding to the discharge region B in which the volume of each pump chamber 17 gradually decreases as the rotor 9 rotates. In addition, a discharge port 20 having a substantially arc shape and a discharge hole 21 communicating with the discharge port 20 are formed, and the oil discharged from each pump chamber 17 by the discharge port 20 and the discharge hole 21 is formed in the bottom 2b of the housing body 2. The pressure chamber 22 is introduced. The oil introduced into the pressure chamber 22 is sent from a discharge passage (not shown) formed inside the housing body 2 to a power cylinder of the power steering device via a predetermined pipe.

  In addition, a flow control valve 23 is provided inside the upper end of the housing body 2 so as to face in a direction orthogonal to the drive shaft 5. As shown in FIG. 6, the flow control valve 23 includes a spool 25 slidably received in a valve hole 24 formed in the housing body 2, and urges the spool 25 in the left direction in the figure. Then, a valve spring 27 is formed between the plug 26 and the tip end of the spool 25 to contact the plug 26 that closes the opening end of the valve hole 24, and the hydraulic pressure upstream of the metering orifice (not shown). That is, a high pressure chamber 28 into which oil in the pressure chamber 22 is introduced, and an intermediate pressure chamber 29 that accommodates the valve spring 27 and into which the oil pressure downstream of the metering orifice is introduced, When the pressure difference between the high pressure chamber 28 and the intermediate pressure chamber 29 exceeds a predetermined value, the spool 25 moves to the right in the figure against the spring pressure of the valve spring 27.

  When the spool 25 is positioned on the left side in FIG. 6, the first fluid pressure chamber P <b> 1 is disposed on the outer peripheral side of the spool 25 via a communication passage 31 that communicates the first fluid pressure chamber P <b> 1 and the valve hole 24. It is connected to the separated low pressure chamber 30. As shown in FIG. 5, low-pressure oil on the suction side is introduced into the low-pressure chamber 30 through a low-pressure oil passage 32 that is branched from the suction passage 19. .

  When the spool 25 slides to the right in FIG. 6 due to the differential pressure between the high pressure chamber 28 and the intermediate pressure chamber 29, the first fluid pressure chamber P1 is disconnected from the low pressure chamber 30. The high pressure chamber 28 is communicated, and high pressure oil is introduced into the first fluid pressure chamber P1.

  In this way, the hydraulic pressure in the low pressure chamber 30 and the hydraulic pressure upstream of the metering orifice are selectively supplied into the first fluid pressure chamber P1.

  On the other hand, the second fluid pressure chamber P2 communicates with the suction port 18 through a communication groove (not shown) formed in the inner side surface 3a of the rear cover 3, so that the low-pressure oil on the suction side is always introduced. It has become.

  The relief valve 33 provided in the spool 25 is configured to reduce the low pressure when the internal pressure of the intermediate pressure chamber 29 reaches a predetermined level or higher, that is, when the hydraulic pressure in the hydraulic power cylinder reaches a predetermined level or higher. The oil in the low pressure chamber 30 is released to the relief passage (not shown) by opening to the chamber 30.

  As shown in FIGS. 3 and 4, the weight member 11 is formed in a substantially semi-annular shape from an iron-based material, and has an inner peripheral side with an outer diameter (outer peripheral radius) r <b> 2 of the bearing housing portion 12. It has a slightly larger predetermined inner diameter (inner peripheral radius) R1 and has a substantially half-moon-shaped notch 34 that can be fitted onto the bearing housing portion 12.

  Further, as shown in FIG. 1, the weight member 11 has an axial length (thickness width) L between the opening end surface 5 a of the pulley 5 and the outer bottom surface 2 c of the housing body 2. It is set slightly shorter than D, and its outer diameter (outer radius) R2 is set slightly smaller than the inner diameter r1 of the accommodation space S of the pulley 5.

  Further, as shown in FIGS. 1 and 3, the weight member 11 has bolt insertion holes 35 and 35 through which the bolts 14 and 14 are inserted at equal intervals in the circumferential direction along the axial direction. It is formed through. As shown in FIGS. 1 and 3, the bolt insertion holes 35, 35 have counterbore portions in which the heads 14 a, 14 a of the bolts 14, 14 are almost buried from the outer surface 11 b side of the weight member 11. 35a and 35a are respectively bored so that the heads 14a and 14a of the bolts 14 and 14 hardly protrude from the outer surface 11b of the weight member 11 when the weight member 11 is attached to the housing body 2. .

  On the other hand, as shown in FIG. 1, the bottom 2b of the housing body 2 has the bolts 14, 4 at predetermined positions corresponding to the bolt insertion holes 35, 35 of the weight member 11, as shown in FIG. Weight mounting screw holes 2d, 2d to which 14 is screwed are formed along the axial direction from the outer bottom surface 2c side.

  Thus, the weight member 11 corresponds to the suction area A with a predetermined radial gap C between the outer peripheral surface 12b of the bearing accommodating portion 12 as shown in FIGS. The bearing housing 12 is attached to the outer bottom surface 2c of the housing body 2 in a state of being fitted so as to surround the upper half portion in the figure.

  The oil pump 1 is attached to the vehicle body via a vehicle body mounting bracket 36 as shown in FIG. The bracket 36 is formed in a substantially U-shaped longitudinal section, and is provided so as to be fitted from the radial direction and to grip both axial ends of the oil pump 1 on the lower end side in the drawing.

  The bracket 36 is formed with a bolt insertion hole 38 through which a plurality of long bolts 37 are inserted in one end portion 36 a facing the outer surface 3 c of the cover member 3. Screw holes 39 through which the respective long bolts 37 are screwed are formed in the other end portion 36b facing the outer bottom surface 2c and at positions facing the respective bolt insertion holes 38, respectively. A counterbore portion 38a in which the head portion 37a of each long bolt 37 is substantially embedded is formed in the outer end portion of each bolt insertion hole 38.

  On the other hand, on the outer bottom surface 2c of the housing body 2 and the outer surface 3c of the cover member 3 corresponding to this, along the axial direction, at predetermined positions corresponding to the bolt insertion holes 38 and the screw holes 39, respectively. Consistent bolt insertion holes 2e, 3d are respectively formed through.

  With this configuration, the bracket 36 has the long bolts 37 inserted into the bolt insertion holes 38 at one end from the outside in the axial direction via the cover member 3 and the bolt insertion holes 3 d and 2 e of the housing body 2. Thus, the oil pump 1 is attached by being screwed into the screw hole 39. A spring washer 40 is interposed between the inner side surface of one end of the bracket 36 and the outer side surface 3c of the cover member 3, thereby preventing the long bolts 37 from loosening.

  Hereinafter, the operation of the oil pump 1 according to the present invention will be described. However, since the basic operation of the pump 1 is well known, the description thereof will be omitted and the oil pump 1 which is a characteristic operation of the present invention will be omitted. Only the damping action during vibration will be described with reference to FIG.

  First, as a basic function of the oil pump 1, when the vibration is generated in the pump 1 due to the pulsation or the like during the operation of the oil pump 1, the weight member 11 having a predetermined weight oscillates. Since it is added to the housing body 2 as a source, the weight of the housing body 2 increases, and the natural frequency of the entire oil pump 1 changes. As a result, especially when resonance with another oscillation source such as an engine occurs, a deviation occurs between the periods of the oscillation of the other oscillation source, and the resonance point for the vibration of the other oscillation source is set. Can be shifted. Thereby, the vibration of the oil pump 1 due to the resonance with the vibration of the other oscillation source is reduced, and the noise based on the vibration is also reduced.

  Therefore, according to this embodiment, the weight member 11 is disposed in the space between the outer bottom surface 2c of the housing body 2 and the opening end surface 5a of the pulley 5 which is normally a dead space. Therefore, the space part of the oil pump 1 can be used effectively, and as a result, vibration of the pump 1 and noise based thereon can be prevented without enlarging the size of the pump 1.

  In addition, since the notch 34 is provided in a part of the outer edge of the weight member 11 so that it can be externally fitted to the bearing housing 12, the weight can be obtained even after the pulley 5 is assembled to the drive shaft 4. The member 11 can be assembled. At this time, the bolts 14 can be tightened via a lightening portion provided on the bottom 5 b of the pulley 5. Therefore, in other words, since the weight member 11 can be replaced with the pulley 5 attached, for example, when a vibration analysis test of the oil pump 1 is performed, the weight is not accompanied by the removal of the pulley 5. The weight and shape of the member 11 and the attachment position can be changed, and the weight member 11 can be easily optimized.

  Furthermore, since the weight member 11 can be externally fitted to the bearing housing portion 12, the weight member 11 can be used as a bearing compared to a case where the weight member 11 is fitted into the bearing housing portion 12 from the axial direction. It can be easily assembled to the accommodating portion 12. Thereby, the assembling workability of the oil pump 1 can be improved, and the manufacturing cost can be reduced.

  In addition, since the housing body 2 is made of an aluminum alloy material and the weight member 11 is made of an iron-based material, the oil pump 1 has a difference in coefficient of linear expansion when the pump 1 generates heat. The bearing housing portion 12 expands more than the weight member 11. However, since the inner diameter R1 of the weight member 11 is set slightly larger than the outer diameter r2 of the bearing accommodating portion 12 and the gap C is provided between the both 11 and 12, the expansion of the weight member 11 is caused by the gap C. The difference of the expansion amount of the bearing housing portion 12 with respect to the amount can be absorbed. For this reason, there is no possibility that the weight member 11 restrains the thermal expansion of the bearing housing portion 12 and generates an internal stress in the bearing housing portion 12, thereby deteriorating the first bearing 13 a housed therein. It will not cause damage.

  Moreover, since the gap C is provided, there is no possibility that the weight member 11 interferes with the bearing housing portion 12 during vibration of the oil pump 1, and as a result, generation of noise due to such interference can be prevented. it can.

  Further, since the weight member 11 is fixed to the housing main body 2 by the two bolts 14 and 14, the coupling force between the both 11 and 2 can be increased, and when the oil pump 1 is vibrated, the weight Since the member 11 and the housing body 2 can be vibrated integrally, it is possible to prevent the generation of noise due to the interference between the members 11 and 2.

  Further, since the weight member 11 is attached only to the housing body 2, the oil pump 1 is delivered or sold in a state in which the weight member 11 is assembled to the housing body 2, that is, in a complete assembly state as an oil pump. be able to.

  FIG. 7 shows a first modification of the present embodiment. In the oil pump 1 according to the embodiment, two pairs of weight members are provided in a state of butting in the radial direction.

  That is, the oil pump 1 includes a weight member 11 having a notch portion 42 that can be fitted to the bearing housing portion 12 in the remaining outer peripheral area of the bearing housing portion 12 on the side of the notch portion 34 of the weight member 11. The second weight member 41 having the same shape as that of the weight member 11 is externally fitted to the weight member 11 from the opposite side in the radial direction, and is fixed similarly to the weight member 11. In this case, the second weight member 41 is attached to the bracket 36 so as not to overlap in the axial direction.

  Therefore, according to this modification, in addition to the operational effects of the above-described embodiment, by utilizing substantially the entire limited space between the housing body 2 and the pulley 5, the weight member 11 It is possible to increase (double) the weight of the housing body 2 without increasing the thickness width L. For this reason, it is possible to obtain a higher damping effect during vibration of the oil pump 1 without increasing the size of the oil pump 1.

  In addition, since the second weight member 41 has the same notch portion 42 as the weight member 11 and is formed so as to be able to be externally fitted to the bearing housing portion 12, the second weight member 41 is driven similarly to the weight member 11. Even after the pulley 5 is assembled to the shaft 4, the second weight member 41 can be assembled. As a result, the assembly of the oil pump 1 can be improved, and the weight and shape of the second weight member 41 can be changed without the pulley 5 being attached and detached. Can be easily performed.

  FIG. 8 shows a second modification of the present embodiment. In the oil pump 1 according to the embodiment, the gap C is set to zero, and the inner periphery of the notch 34 of the weight member 11 is shown. The weight member 11 is fixed to the housing body 2 in the same manner as in the above-described embodiment in a state where the surface is in contact with the outer peripheral surface 12b of the bearing housing portion 12.

  That is, in the oil pump 1, as shown in FIG. 6, the upper half of the drawing is a suction area A where the pressure is low, and the lower half is a discharge area B where the pressure is high. The shaft 4 is pressed toward the suction region A by the discharge pressure of the pump and is slightly deformed in the same direction, which may cause the drive shaft 4 to be misaligned. As a result, the misalignment of the drive shaft 4 may change the cam profile of the pump to cause pulsation, thereby inducing vibration of the oil pump 1.

  However, in the case of the oil pump 1 according to this modification, the weight member 11 is disposed on the suction area A side where the pressure is low, so that the drive shaft 4 is deformed based on the discharge pressure of the pump as described above. Can be effectively suppressed. As a result, the shaft misalignment of the drive shaft 4 is suppressed, and the occurrence of pulsation of the oil pump 1 associated therewith can be suppressed. Therefore, the generation of vibration based on the pulsation and the accompanying noise are reduced. can do.

  FIG. 9 shows a third modification of the present embodiment. In the oil pump 1 according to the embodiment, the thickness width L of the weight member 11 is set between the housing body 2 and the pulley 5. The outer end portion 11a is set to be accommodated in the accommodating space S of the pulley 5 in the attached state.

  Therefore, according to this modification, since the outer end portion 11a of the weight member 11 is housed in the housing space S of the pulley 5, the housing space that acts as a resonance space when the oil pump 1 vibrates. The volume of S will be reduced, and thereby the resonance action in the accommodation space S when the oil pump 1 vibrates can be reduced. As a result, noise based on the resonance action is reduced, and noise generated with vibration of the oil pump 1 can be reduced.

  If the second weight member 41 is provided in addition to the weight member 11 as in the first modification, it is possible to further reduce the volume of the resonance space, whereby the oil pump 1 It is possible to further reduce the resonance effect in the accommodation space S due to the vibration of. As a result, it is possible to further reduce noise due to the resonance action, and to obtain a higher noise prevention effect when the pump 1 vibrates.

  FIG. 10 shows a second embodiment of the present invention. The basic configuration is the same as that of the third modification of the first embodiment, except that the other end 36b of the bracket 36 is different. Extending and interposing between the housing body 2 and the weight member 11 and fixing the other end 36b together with the weight member 11 to the housing body 2 and changing the shape of the weight member 11 It is a thing.

  That is, the other end portion 36b of the bracket 36 is substantially the same diameter as each bolt insertion hole 35, 35 of the weight member 11 at a predetermined position corresponding to each weight mounting screw hole 2d, 2d of the housing body 2. The second bolt insertion holes 43 and 43 are respectively formed through. The bolts 14 and 14 are screwed into the weight mounting screw holes 2d and 2d through a series of through holes including the second bolt insertion holes 43 and 43 and the bolt insertion holes 35 and 35. Thus, the other end 36 b is fastened together with the weight member 11 to the housing body 2.

  Further, the weight member 11 has a large-diameter flange portion 11c having an outer diameter R3 substantially the same as the outer diameter r3 of the pulley 5 at the inner end portion (the axial end portion on the housing body 2 side). It protrudes in the radial direction and is inserted with a slight gap between the axial direction between the outer bottom surface 2c of the housing body 2 and the opening end surface 5a of the pulley 5.

  Therefore, according to this embodiment, since the bracket 36 is integrally fixed to the housing main body 2 together with the weight member 11, the bracket 36 particularly serves to improve the rigidity of the housing main body 2. Can be more effectively suppressed.

  As described above, the other end portion 36b of the bracket 36 is interposed between the housing body 2 and the weight member 11, so that the thickness width L of the weight member 11 is increased by the thickness width of the bracket 36. However, since the flange portion 11c is provided in the weight member 11, the space portion formed between the housing body 2 and the pulley 5 in the axial direction is used more effectively. It becomes possible to compensate the weight of the weight member 11 based on the minutes. As a result, a high vibration damping effect by the weight member 11 similar to that of the first embodiment can be obtained without increasing the thickness width L of the weight member 11.

  The present invention is not limited to the configuration of each embodiment described above, and in particular, the shape and size of the weight member 11 can be freely changed according to the specifications and applications of the oil pump 1.

  For example, as shown in FIG. 11 for the weight member 11 according to the first embodiment, and as shown in FIG. 12 for the weight member 11 according to the second embodiment, respectively. The weight member 11 may have a shape in which the circumferential ends 11d and 11d are extended. In this case, the weight of the housing body 2 can be increased without increasing the thickness width L of each weight member 11, and the vibration of the oil pump 1 can be increased without increasing the size of the oil pump 1. The vibration control effect at the time can be enhanced.

  Further, in each of the weight members 11 according to the first and second embodiments, chamfered portions 11e and 11e as shown in FIGS. 11 and 12 are formed at the respective circumferential end portions 11d and 11d. May be. In this case, when the weight member 11 is assembled to the housing body 2, the weight member 11 can be easily fitted to the bearing housing portion 12, and the assembly of the weight member 11 can be improved. It can also be used as an adjustment allowance for the weight of the weight member 11.

  Furthermore, the weight member 11 according to the first embodiment can be formed in a rectangular shape as shown in FIG. The weight member 11 having such a shape is particularly effective when the outer shape of the housing body 2 is formed in a rectangular shape, and in this case also, the thickness width L of the weight member 11 is increased. The weight of the housing body 2 can be increased.

  Moreover, the 2nd weight member 41 which concerns on the 1st modification of the said 1st Embodiment should just be provided in the outer periphery area of the remainder of the said bearing accommodating part 12, and the same shape as the said weight member 11 is sufficient. It is not limited to what it has, but can be freely changed according to the shape of the weight member 11.

1 is a partial cross-sectional view showing a first embodiment of an oil pump according to the present invention and showing features of the present invention. It is a side view of the oil pump which shows the embodiment. It is a perspective view of the oil pump before pulley attachment. It is the arrow view seen from the A direction of FIG. It is the BB sectional view taken on the line of FIG. It is CC sectional view taken on the line of FIG. It is a front view of the oil pump which shows the 1st modification of the embodiment. It is a front view of the oil pump which shows the 2nd modification of the embodiment. It is a fragmentary sectional view which shows the 3rd modification of the embodiment and shows the characteristic of this invention. It is a fragmentary sectional view which shows 2nd Embodiment of the oil pump which concerns on this invention, and shows the characteristic of this invention. It is a perspective view which shows the other example of the shape of the weight member which concerns on 1st Embodiment. It is a perspective view which shows the other example of the shape of the weight member which concerns on 2nd Embodiment. It is a perspective view which shows the other example of the shape of the weight member which concerns on 1st Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Oil pump 2 ... Housing main body 2a ... Pump accommodating chamber 4 ... Drive shaft 5 ... Pulley (power transmission member)
6 ... Adapter ring (pump element)
8 ... Cam ring (pump element)
9 ... Rotor (pump element)
DESCRIPTION OF SYMBOLS 11 ... Weight member 12 ... Bearing accommodating part 13a ... 1st bearing (bearing)
34 ... Notch

Claims (9)

A housing body having a pump housing chamber therein;
A bearing housing part that is provided at one axial end of the housing body so as to protrude along the axial direction, has a smaller outer shape than the housing body, and houses a bearing therein;
A drive shaft that is rotatably supported by the bearing, and is disposed so that at least one axial end side protrudes from the bearing housing portion side;
A pump element that is housed in the pump housing chamber and sucks and discharges oil by being driven to rotate by the drive shaft;
A power transmission member provided on one end side of the drive shaft and transmitting a drive force to the drive shaft;
While providing a weight member fixed to the housing body on the outer peripheral side of the bearing housing portion,
An oil pump, wherein the weight member is provided with a notch portion that can be fitted onto the bearing housing portion. A housing body having a pump housing chamber therein;
A cover member that is axially opposed to the housing body and closes the pump housing chamber;
A bearing housing part that is provided so as to protrude in the axial direction at an axial end opposite to the cover member in the housing body, has a smaller outer shape than the housing body, and houses a bearing therein;
A drive shaft that is rotatably supported by the bearing, and is disposed so that at least one axial end side protrudes from the bearing housing portion side;
A rotor housed in the pump housing chamber and driven to rotate by the drive shaft;
Vanes provided in a plurality of slots provided radially in the radial direction of the rotor so as to freely appear and disappear;
A cam ring which is swingably provided in the pump housing chamber and forms a plurality of pump chambers together with the rotor and each vane on the inner peripheral side;
An annular member disposed on the opposite side to the cover member with respect to the cam ring and sandwiching the cam ring together with the cover member;
A suction port which is provided on at least one side of the cover member or the annular member and opens to a region where the volume of each pump chamber increases, and a discharge port which opens to a region where the volume of each pump chamber decreases;
A seal member that is provided on the outer peripheral side of the cam ring and separates an annular space between the outer peripheral surface of the cam ring and the peripheral wall of the pump housing chamber into a first fluid pressure chamber and a second fluid pressure chamber;
A power transmission member provided on one end side of the drive shaft and transmitting a drive force to the drive shaft;
While providing a weight member fixed to the housing body on the outer peripheral side of the bearing housing portion,
An oil pump, wherein the weight member is provided with a notch portion that can be fitted onto the bearing housing portion. The notch is formed to have an opening on a region corresponding to the discharge port, and the weight member is provided so as to surround the region corresponding to the suction port with respect to the bearing housing portion. The oil pump according to claim 2. The housing body is formed of an aluminum alloy material, while the weight member is formed of an iron-based material,
The oil pump according to claim 1, wherein a predetermined gap is provided between the weight member and the bearing housing portion. 3. The oil pump according to claim 1, wherein a second weight member is provided facing the notch portion side of the weight member. 4. Forming a recess at the axial end of the power transmission member on the housing body side;
The oil pump according to claim 1 or 2, wherein at least a part of the weight member is accommodated in the recess. 3. The oil pump according to claim 1, wherein the weight member is integrally fastened to the housing body together with a bracket for mounting a vehicle body by a common bolt. The oil pump according to claim 1 or 2, wherein the weight member is fixed to the housing body with a plurality of bolts. The oil pump according to claim 1, wherein the weight member is attached only to the housing main body.

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