JP2001050175A - Vane pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent pulsation of discharge pressure by compensating positional slippage in the circumferential direction against a cam ring of a side plate on which a suction port and a discharge port are formed. SOLUTION: Communicating passages 331, 332 are formed by applying chamfering on a side wall corresponding to a suction cam part 291 and a discharge cam part 292 of a cam ring 29R. Communication of a pump chamber 341 and a suction port 37R partitioned between a vane 35 and a preceding vane 35 is blocked at a position slightly before the vane 35 reaches a terminal end of the suction cam part 291, and communication of the pump chamber 341 and the suction side communicating passage 331 is blocked instantly when the vane 35 reaches a terminal end of the discharge cam part 292. Additionally, the pump chamber 341 and the discharge side communicating passage 332 partitioned between the vans 35 and a following vane 35 are communicated to each other instantly when the vans 35 reaches a starting end of the discharge cam part 292, and immediately after it, the pump chamber 341 and a discharge port 38R are communicated to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vane pump in which a radially outer end of a vane slidably supported in a vane groove radially formed in a rotor abuts an inner peripheral surface of a cam ring.

[0002]

2. Description of the Related Art In a four-wheel drive vehicle provided with main drive wheels to which the driving force of an engine is directly transmitted, and auxiliary drive wheels to which the driving force is distributed from the main drive wheels via a hydraulic coupling device. Japanese Patent Laid-Open Publication No. Hei 3 (1994) discloses a hydraulic coupling device comprising a pair of vane pumps.
These are known from JP-A-104736 and JP-A-1-153335.

In such a vane pump, a cam ring and a rotor are defined on an outer side and an inner side in a radial direction, respectively.
And a working chamber partitioned on both sides in the axial direction by a pair of side plates, and a plurality of vanes supported radially slidably by the rotor and having a radially outer end abutting against the inner peripheral surface of the cam ring. By moving in the working chamber with rotation, the working oil sucked from a suction port provided at one end of the working chamber is discharged from a discharge port provided at the other end of the working chamber.

[0004]

FIG. 17A shows a conventional vane pump, in which the movement locus of the vane is linearly developed. When multiple vanes 35 ... slidably supported on the rotor 32 is moved being guided by the inner peripheral surface of the cam ring 29 having a suction cam portion 29 ₁ and the discharge cam portion 29 ₂ from the left side in the figure to the right, a pair of adjacent vanes 35, 35 the volume of the pump chamber 34 ₁ formed between the enlarged or reduced. Cam ring 29 and rotor 3
The side plate 28 covering the side surface of the suction cam portion 2
9 and the discharge port 38 facing the suction port 37 and the discharge cam portion 29 ₂ facing the ₁ is formed, the working oil from the suction port 37 to the pump chamber 34 ₁ is drawn when the volume of the pump chamber 34 ₁ is increased When the volume of the pump chamber 34 ₁ decreases, the pump port 34 ₁
The hydraulic oil is discharged to.

[0005] According to such a vane pump, Fig. 17 (B), the pump chamber 34 at _the moment _when the _first volume is maximized, i.e. the rotation direction leading side of the vane 35 is discharged cam section 2
9 ₂ reaches the starting end, and the moment the rotating direction delayed side of the vane 35 has reached the end of the suction cam portion 29 _1, the pump chamber 34
₁ must communicate with the discharge port 38, and communication between the pump chamber 34 ₁ and the suction port 37 must be cut off.

However, when assembling the cam ring 29 and the side plate 28, as shown in FIG. 17C, if the phase of the side plate 28 is shifted toward the rotation direction advance side of the rotor 32 due to an assembly error, Pump room 3
4 _{because one} of the pump chambers 34 ₁ when the volume starts to decrease is in communication with yet suction port 37 without communicating with the discharge port 38, hydraulic oil flows back from the pump chamber 34 ₁ into the suction port 37 Pulsation of the discharge pressure occurs. vice versa,
As shown in FIG. 17 (D), the phase of the side plate 28 by assembly error is shifted in the rotational direction delayed side of the rotor 32, the pump chamber when the volume of the pump chamber 34 ₁ is still increased since 34 ₁ communicates with the suction port 37 is cut off communicating with the discharge port 38, hydraulic oil pulsation of backflow to discharge pressure from the discharge port 38 into the pump chamber 34 ₁ is generated.

[0007] The pulsation of the discharge pressure of the vane pump may be caused by a processing error in which the distance between the end of the suction port 37 and the start of the discharge port 38 is too large, or the end of the suction port 37 and the discharge. This also occurs when the distance between the starting ends of the ports 38 is too small.

[0008] As shown in FIG. 18, before the tip of the vane 35 has finished down the discharge cam portion 29 _2, the communication between the front surface of the vane 35 and the discharge port 38 is cut off (see point a), the vane The hydraulic oil trapped in front of 35 is compressed, causing a water hammer phenomenon, which also causes a discharge pressure pulsation.

The present invention has been made in view of the above circumstances, and in a vane pump, displacement of a side plate, in which a suction port and a discharge port are formed, with respect to a cam ring in a circumferential direction is compensated to prevent pulsation of a discharge pressure. The purpose is to do.

[0010]

To achieve the above object, according to the first aspect of the present invention, a cam ring having a suction cam portion and a discharge cam portion formed on an inner peripheral surface thereof, and a cam ring having a cam ring and a discharge cam portion formed inside the cam ring. A rotatably housed rotor, a side plate that covers both sides of the cam ring and the rotor, and a radially outer end abutting on the inner peripheral surface of the cam ring slidably supported by a plurality of vane grooves formed radially on the rotor. A plurality of vanes in contact with each other, a pump chamber partitioned by two adjacent vanes, a cam ring, and a rotor and having a volume that expands and contracts with the rotation of the rotor, and a side plate formed to face the suction cam portion. A suction port, and a discharge port formed in a side plate so as to face the discharge cam portion. A vane pump for discharging oil from a pump chamber having a reduced volume to a discharge port is characterized in that a communication passage is formed in a suction cam portion and a discharge cam portion of a cam ring to allow hydraulic oil to escape in a circumferential direction across a vane. A vane pump is proposed.

[0011] According to the above structure, the communication passage for allowing the hydraulic oil to escape in the circumferential direction across the vane is formed between the suction cam portion and the discharge cam portion of the cam ring. The discharge port is substantially at the beginning and the beginning of the communication path of the discharge cam portion is substantially the start of the discharge port.
Since the communication passage is formed in the cam ring in which the suction cam portion and the discharge cam portion are formed, even if the side plate in which the suction port and the discharge port are formed is out of phase with respect to the cam ring, the suction cam portion and the side plate correspond to each other. There is no danger that the positional relationship between the communication passage and the discharge cam portion and the corresponding communication passage will be shifted. Therefore, the end of the suction port is located on the delay side in the rotor rotation direction from the end of the communication passage corresponding to the suction cam portion, and the start end of the discharge port is in the rotor rotation direction more than the start end of the communication passage corresponding to the discharge cam portion. If there is some error in the phase between the side plate and the cam ring, the timing difference at the moment when the pump chamber separates from the suction port and the timing at the moment when the pump chamber communicates with the discharge port is provided. Pulsation of the pump discharge pressure can be prevented.

According to the second aspect of the present invention,
In addition to the configuration of the first aspect, a vane pump is proposed in which the communication passage is formed by chamfering side walls of a suction cam portion and a discharge cam portion of a cam ring.

According to the above construction, since the communication passage is formed by chamfering the side walls of the suction cam portion and the discharge cam portion of the cam ring, machining of the communication passage becomes easy.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on embodiments of the present invention shown in the accompanying drawings.

1 to 16 show a first embodiment of the present invention. FIG. 1 is a skeleton diagram of a power transmission device of a four-wheel drive vehicle, and FIG. 2 is a longitudinal sectional view of a hydraulic coupling device. 3 is a sectional view taken along line 3-3 in FIG. 2, and FIG.
5, FIG. 5 is a sectional view taken along line 5-5 of FIG. 2, FIG. 6 is a sectional view taken along line 6-6 of FIG. 2, FIG. 7 is an enlarged view of a main part of FIG.
FIG. 9 is a sectional view taken along line 8-8 of FIG.
10 is a perspective view of the orifice plate, FIG. 11 is an enlarged view of a main part of FIG. 3, FIG. 12 is a sectional view taken along line 12-12 of FIG. 11, FIG. 13 is an explanatory view of the operation of the orifice plate, and FIG. FIG. 15 is a graph for explaining FIG.
FIG. 16 is a hydraulic circuit diagram of the hydraulic coupling device.

As shown in FIG. 1, a four-wheel drive vehicle V has an engine E disposed horizontally in front of a vehicle body, and an engine E
And a transmission M coupled to the right side surface of the transmission.
A first power transmission system D _{1 for} transmitting the driving force of the transmission M to the left and right front wheels W _FL and W _FR as main driving wheels includes a first spur gear 2 provided on an output shaft 1 of the transmission M, and a first spur gear 2. Second spur gear 3 meshing with
A bevel gear type front differential 4 driven by the second spur gear 3, and a front wheel W extending left and right from the front differential 4 as a main drive wheel.
It is composed of left and right axles 5 _L and 5 _R connected to _FL and W _FR .

A second power transmission system D for transmitting the driving force of the first power transmission system D ₁ to rear wheels W _RL and W _RR as auxiliary driving wheels.
Reference numeral ₂ denotes a third spur gear 6 provided in a differential box of the front differential 4, a fourth spur gear 7 meshing with the third spur gear 6, a first bevel gear 8 which rotates integrally with the fourth spur gear 7, and a first bevel gear 8 A second bevel gear 9 meshing with a propeller shaft 10 having a second bevel gear 9 at the front end and extending rearward of the vehicle body; a third bevel gear 11 provided at the rear end of the propeller shaft 10;
A fourth bevel gear 12 meshing with the bevel gear 11;
Comprising a hydraulic coupling device H which is driven by the bevel gear 12, the rear wheels W _RL extends horizontally from the hydraulic coupling device H, and W left and right axles 13 _L connected to the _RR, 13 _R.

Next, the structure of the hydraulic coupling device H will be described with reference to FIG.

The hydraulic coupling device H is provided with a casing 24 formed by connecting a substantially disk-shaped left casing 21 and a substantially cup-shaped right casing 22 with bolts 23. It is rotatably supported in the housing 20 by bearings 19 _L, 19 _R. The right casing 22 is fastened together with the fourth bevel gear 12 by bolts 23. Therefore, the rotation of the propeller shaft 10 is transmitted to the casing 24 via the third bevel gear 11 and the fourth bevel gear 12. And the right end of the left rotor shaft 14 _L passing through the central portion of the left casing 21 is connected to the axle 13 _L of the left rear wheel W _RL, is connected to the axle 13 _R of the right rear wheel W _RR central portion of the right casing 22 and the left end of the right rotor shaft 14 _R penetrating the opposes coaxially inside the casing 24.

The left rotor shaft 14 rotatably supported by the left casing 21 and a second side plate 30 to be described later via a pair of ball bearings 25 _L and 26 _{L.
In L} , a seal member _27L is arranged between the outer peripheral surface and the left casing 21. A pair of ball bearings 2
5 _R and 26 _R via the right casing 22 and the second
The right rotor shaft 14 _R rotatably supported by the side plate 30 has a seal member 27 _R disposed between the outer peripheral surface and the right casing 22.

Inside the casing 24 is a left vane pump.
P_LAnd right vane pump P_RAre arranged symmetrically
You. That is, the first left side is inside the casing 24.
Plate 28_L, Left cam ring 29_L, 2nd side play
Port 30, right cam ring 29 _RAnd right first side play
Port 28_RAre laminated in the axial direction, and their outer peripheral surfaces
Are spline fittings 31 on the inner peripheral surface of the right casing 22.
(See FIGS. 3 to 7) to prevent the casing 24 from rotating.
Is Left rotor shaft 14_LSpline joined to
Left rotor 32_LIs the first left side plate 28_L,
Left cam ring 29 _LAnd surrounded by the second side plate 30
Is rotatably stored in the enclosed space.
To 14_RRotor 32 spline-coupled to_RBut right
First side plate 28_R, Right cam ring 29_Rand
Rotatable in the space surrounded by the second side plate 30
Will be delivered. The second side plate 30 is a left vane pump P
_LAnd right vane pump P_RComponents common to
And the ball bearing 26_L26_RTo
Via the left rotor shaft 14_LAnd right rotor shaft
14_RAre supported so as to be rotatable relative to each other.

[0022] As is apparent from FIGS. 6 and 7, is arranged left spacer 49 _L of an annular between the right side and the left the left side of the first side plate 28 _L of the left casing 21, the left side of the right casing 22 Face and right first side plate 28 _R
Annular right spacer 49 _R is disposed between the right side of the. Right rotor shaft 14 _R axis six hexagon socket bolt disposed on a circle centered on the 50 ... are screwed from the outside to the inside of the right casing 22, the leading end of the first right side plate 28 _R Contact the right side. The outer surfaces of the left and right spacers 49 _L and 49 _R each have three grooves 49 ₁ .
Are formed radially, and the lubricating oil in the casing 24 can move through the grooves 49 ₁ . The outer surface of the right casing 22 is formed with a radial rib 22 ₁ ... six recesses 22 ₂ ... enclosed, the bolt by accommodating the bolts 50 ... head of each recess 22 ₂ Are prevented from being damaged or loosened by contact with other objects.

The left casing 21 is provided with a lubricating oil supply port 54 for filling the casing 24 with lubricating oil, and the lubricating oil supply port 54 is closed by a bolt 55.

Next, detailed description of the structure of the right vane pump P _R with reference also to FIGS. Since the structure of the left vane pump P _L is the structure and the left and right mirror-symmetrical right vane pump P _R, duplicate explanation is omitted. Corresponding components of the right and left vane pumps P _R and P _L have the same reference numerals with the respective suffix “ _R ”.
And the suffix " _L ".

The inner peripheral surface of the right cam ring 29 _R has become a general triangular, circular right rotor 3 housed therein
Between the 2 _R, 3 pieces of working chambers 34 _R spaced by 120 ° in the circumferential direction ... is formed. Right rotor 32 has eight respective vane grooves 32 ₁ ... in the plate-shaped vanes 35 ... formed radially in _R is slidably supported, they vanes 35 ... radially outer ends of the right cam ring 29 _R Sliding contact with the inner peripheral surface of Right in the first left side of the side plate 28 _R and the right side surface of the second side plate 30, the vanes 35
Radially outer end so as to close contact with the inner circumferential surface of the right cam ring 29 _R to each annular vane push-up port 28 _1, 3
0 ₁ is formed. These vane push-up ports 28 ₁ , 3
0 ₁ communicates with the bottoms of the eight vane grooves 32 ₁ ... Of the right rotor 32 _R. Also in order to close contact with the inner circumferential surface of the right cam ring 29 _R a radially outer end of each vane 35, the coil spring 36 is mounted under compression between the radially inner end of the bottom and the vane 35 of the vane grooves 32 _1.

[0026] As is apparent from FIGS. 7-9, the cross-sectional shape of the coil spring 36 is oval with a shorter diameter d ₂ in the circumferential direction has a major axis d ₁ in the axial direction of the right rotor 32 _R Shaped. The minor diameter d of the coil spring 36
₂ is set to be substantially equal to the groove width of the vane grooves 32 _1,
This prevents the coil spring 36 from falling down in the circumferential direction. Moreover the inclination of the axial direction of the coil spring 36, the major diameter d ₁ is reliably prevented by that along the axial direction. The radially outer end of the coil spring 36 is fitted into a trapezoidal cutout 35 ₁ (see FIG. 7) formed at the radially inner end of the vane 35, thereby positioning the coil spring 36 in the axial direction. be able to.

By making the cross section of the coil spring 36 elliptical as described above, the capacity can be increased as compared with a coil spring having a circular cross section that can be arranged in the same space. As a result, increase the number of coil springs to increase the capacity,
There is no need to increase the wire diameter, reduce the number of windings, or lengthen the set length. The number of components increases as the number of coil springs increases, and the coil springs increase as the wire diameter increases. It is possible to prevent an increase in the contact height of the steel, an increase in plastic deformation, an increase in plastic deformation due to a decrease in the number of windings, an increase in the number of processing steps for the vane due to a longer set length, and a fall of the coil spring. it can.

Further radial Since the external notch 35 ₁ of the vane 35 to be fitted is formed in a trapezoidal shape, a coil spring 36 which is compressed notch 3 of the coil spring 36
5 not only from biting ₁ can be prevented, it is possible to automatically center the coil spring 36 in the axial direction.

As is apparent from FIGS. 2 to 4 and 13, on the right side surface of the second side plate 30, 3 facing each three working chambers 34 _R ... circumferential ends of the right vane pump P _R The three suction ports 37 _R ... And the three discharge ports 38 _R. Two adjacent working chambers 34
Suction port 3 provided at the opposite part of _R , 34 _R
7 across the _R and the discharge port 38 _R, the orifice plate supporting groove 39 _R extending in the radial direction is recessed. Orifice plate supporting groove 39 _R comprises a support part 39 ₁ located radially outward, and a groove portion 39 ₂ which extend radially inward from the support portion 39 _1.

The left and right vane pumps P_L, P_RIs
When the engine rotates forward, the hydraulic oil is supplied to the suction port 37._L, 37_RSucking from
Enter and discharge port 38_L, 38_RDischarge from the
Discharge port 38 at reverse rotation_L, 38_RInhaled from
And suction port 37_L, 37 _RDischarge from.

As shown in FIG. 10, the orifice plate 40 _R is supported swing freely in the orifice plate supporting groove 39 _R comprises a part cylindrical pivot portion 40 _1, a plate-shaped extending from the fulcrum portion 40 ₁ It is composed of a valve portion 40 ₂ which, in the valve portion 40 ₂ first orifice 41 _R for communicating both sides thereof are formed so as to penetrate. The cutout 42 is applied to one edge of the valve portion 40 ₂ of the orifice plate 40 _R. As shown in FIG. 13, the orifice plate 40 _R having the above structure, the fulcrum portion 40 ₁ is fitted into the supporting portion 39 ₁ of the orifice plate supporting groove 39 _R, the valve portion 40 ₂ of the orifice plate supporting groove 39 _R Groove 39
Rocks inside ₂ .

As is clear from FIGS. 3 and 7, the orientation
Fiss plate 40_RFulcrum 40 ₁Radially outside of
The half part is the right side that contacts the right side of the second side plate 30.
Cam ring 29_RIs held down by This
Orifice plate 40_RIs the right rotor 32_RMove to the side
Orifice plate 40_RThe edge of
Interference with the edges of the vanes 35 is prevented.

Further the outer peripheral surface of the rotor 32 _R and the cam ring 2
9 because there is a slight gap between the inner peripheral surface of the _R, a gap is present between the supporting portion 39 ₁ of the orifice plate 40 _R fulcrum 40 ₁ and the orifice plate supporting groove 39 _R of inhalation port 37 _R and the discharge port 38 _R and the gap between the fulcrum 40 ₁ and the support portion 39 _1, will communicate with each other via the gap between the rotor 32 _R and the cam ring 29 _R, undesired actuation Oil leaks can occur. However, since actually fitted swingably and liquid tight to the support portion 39 ₁ of the orifice plate 40 _R fulcrum 40 ₁ and the orifice plate supporting groove 39 _R of the fulcrum 40 ₁ and the support portion 39 ₁
Undesirable leakage of hydraulic oil through the gap therebetween can be reliably prevented.

The right vane pump P orifice plate supporting groove 39 _R and the orifice plate 40 _R of _R constitutes a switching valve V _R, also left vane pump P _L orifice plate supporting groove 39 _L and the orifice plate 40 of
_L constitutes the switching valve _VL .

As is clear from FIGS. 2 and 4, the second
And three suction ports 37 _R ... right vane pump P _R that is recessed to the right side surface of the side plate 30, the third left vane pump P _L which is recessed in the left side surface of the second side plate 30
The number of suction ports 37 _L ... are disposed opposite to each other, the corresponding suction port 37 of the right vane pump P _R to _R ... and suction port 37 _L ... and left vane pump P _L is, the second side plate 30 are connected through three second orifices 43. The right vane pump P 3 of _R that is recessed to the right side surface of the second side plate 30
A number of discharge ports 38 _R ..., is recessed been the three discharge ports 38 _L ... left vane pump P _L to the left side surface of the second side plate 30 is disposed at a position facing each other, the corresponding the discharge port 38 _R of the right vane pump P _R ...
Suction port 38 of the left vane pump P _L and _L ... and is, the second
Three second orifices 4 penetrating the side plate 30
3 are connected.

The second orifices 43 are formed with suction ports 37 _{L formed} on both sides of the second side plate 30.
Are formed so as to be connected between the bottom surfaces of the 37 _R and the discharge ports 38 _L and 38 _L. Therefore, there is no possibility that the second orifices 43 are blocked by the side end surfaces of the vanes 35.

As is apparent from FIGS. 2 and 5, the right to the left side surface of the first side plate 28 _R, 3 pieces of suction ports formed in the right side surface of the second side plate 30 37 _R
... and has three discharge ports 38 _R ... is three intake ports 37 _R ... and three discharge ports 38 _R ... is recessed opposite the three of the first right side plate 28 _R
Number of suction port 37 _R ... and three of the discharge port 38 _R
... is in communication with said right right side of the first side plate 28 _R via a total of six check valves 44 _R .... The check valves 44 _R are arranged from the right side of the right first side plate 28 _R to the suction port 37 _R and the discharge port 38 _R.
... allows hydraulic oil to flow to the side, and restricts the flow of hydraulic oil in the opposite direction.

[0038] As is apparent from referring also to FIG. 15, each check valve 44 _R includes a first right side plate 28 _R of the intake ports 37 _R and a discharge port 38 _R of the valve seat that is recessed in the bottom surface 28 ₂ is constructed from the valve seat 28 ₂ to be seated a check ball 58., the check ball 58 when the suction port 37 _R and the discharge port 38 _R is a high pressure closed seated on the valve seat 28 _2, inhalation port 37 _R and a discharge port 38 _R is check ball 58 becomes a low pressure to open the valve away from the valve seat 28 _2.

The first right this way, the check valve 44 _R
By providing inside the side plate 28 _R, it suppresses the length of the oil passage leading to the check valve 44 _R to a minimum, an increase in the number of parts can be minimized. Since the first right side plate 28 _R intake ports 37 _R and the discharge port 38 _R on the right rotor 32 _R of faces, check ball 5 at its right rotor 32 _R
8 can be regulated.

[0040] As is apparent from FIGS. 2 and 7, the cylinder 14 ₂ so as to penetrate the inside of the right and left rotor shafts 14 _L, 14 _R in the axial direction, 14 ₂ are formed,
The inner end of the cylinder 14 _2, 14 ₂ communicates with the internal space of the left and right vane pumps P _L, P _R, the outer end communicates with the atmosphere. Each cylinder 14 _2, 14 ₂ to the piston 45 _L, 4
5 _R are slidably fitted, and each piston 4
5 _L, 45 by two O-rings 46 and 47 supported to the annular groove 45 _1, 45 ₂ formed on the outer periphery of the _R, the piston 4
5 _L, 45 _R and the cylinder 14 _2, 14 ₂ of the sliding surface is sealed. Between the left and right of the rotor shaft 14 _L, 14 shaft end facing each of the _R, washers 48 of the piston 45 _L, 45 _R is prevented from entering the opposite side of the cylinder 14 _2, 14 in ₂ is arranged You.

Thus, the vane pump P_L, P_RFor driving
When the hydraulic oil expands due to the heat generated, one of the hydraulic oil
Part is rotor shaft 14_L, 14_RThe opposite shaft ends
Cylinder 14_Two, 14_TwoPenetrate the inside of a pair of pi
Ton 45_L, 45_RMove in the direction away from each other
Absorbs hydraulic fluid expansion. Conversely, vane pump P_L, P_Rof
When the hydraulic oil shrinks due to the temperature drop due to operation stop, a pair of
Piston 45_L, 45 _RMove toward each other
To absorb the contraction of hydraulic oil. In this way, the number of parts
The simple structure ensures the effects of thermal expansion and contraction of the hydraulic oil.
Remove it to prevent air from entering the hydraulic fluid.
Can be. In particular, a pair of pistons 45 _L, 45_RContact
Absorbs hydraulic fluid expansion and contraction by approaching and separating
Therefore, it is necessary to secure a sufficient volume of hydraulic oil that can be absorbed.
it can.

As is clear from FIGS. 11 and 12,
The three working chambers 34 _R formed in the cam ring 29 _R are:
Intake cam portion 2 the radius increases gradually in the direction of rotation of the rotor 32 _R
9 includes ₁ and a radius a discharge cam portion 29 ₂ which gradually decreases in the rotational direction of the rotor 32 _R, and a circular arc portion 29 ₃ constant radius that connects the starting end of the suction cam portion 29 ₁ of the end and the discharge cam portion 29 ₂ . The first side plate 28 _R and the second side plate 30 that sandwich the cam ring 29 _R, together with the intake port 37 _R, 37 _R are formed respectively so as to face the intake cam 29 _1, the ejection cam portion 29 ₂ Discharge ports 38 _R , 38 _R are formed so as to face each other.
Cam ring 29 _R opposite to the first side plate 28 _R
Of the suction cam portion 29 ₁ and the discharge cam portion 29
Suction side communication passage 33 ₁ and the discharge-side communication passage 33 ₂ is formed by chamfering along _two. FIG. 12 is shown clearly cross-sectional shape of the suction-side communicating passage 33 _1. Thus, since the chamfered side walls of the cam ring 29 _R forming the suction-side communicating passage 33 ₁ and the discharge-side communication passage 33 _2,
Its working of the suction-side communicating passage 33 ₁ and the discharge-side communication passage 33 ₂ is facilitated.

As is apparent from FIG. 11, the pump chamber 34 ₁ partitioned between the vane 35 and the preceding vane 35 is located at a position slightly before the vane 35 reaches the end of the suction cam portion 29 _1. is cut off communicating with the port 37 _R, the moment the vane 35 has reached the end of the suction cam portion 29 _1, the communication between the suction side communication passage 33 ₁ and the pump chamber 34 ₁ is cut off. Further the moment the vane 35 reaches the starting end of the discharge cam portion 29 _2, subsequent vane 35 and its vane 35
Between the pump chamber 34 ₁ and the discharge side communication passage 33
₂ and are communicated, and the pump chamber 34 ₁ immediately after the discharge port 38 _R communicate with each other.

The suction side communication passage 33 ₁ and the discharge-side communicating passage 3
3 in a portion _{where 2} is present, since the hydraulic oil through these suction side communication passage 33 ₁ and the discharge-side communication passage 33 ₂ so as to straddle the vane 35 can move, the suction port 37 even if the vane 35 is interposed between _R and the end of the suction-side communicating passage 33 ₁ communicates always the beginning of the discharge port 38 _R and the discharge-side communication passage 33 ₂ is always communicated. Therefore, the suction side communication passage 3
3 ₁ end becomes Substantial end of the intake port 37 _R,
Starting the discharge side communication passage 33 ₂ is Substantial beginning of the discharge port 38 _R. And since the intake cam 29 ₁ and the discharge cam portion 29 ₂ and the suction side communication passage 33 ₁ and the discharge-side communication passage 33 _2, it is provided on the same cam ring 29 _R, by inhalation assembly errors cam portion 29 ₁ and the intake without circumferential positional relationship of the side communication passage 33 ₁ is displaced,
Circumferential positional relationship between the discharge cam portion 29 ₂ and the discharge-side communication passage 33 ₂ can not be displaced.

As described above, the first side plate 28 _R and the second side plate 30 are not attached to the cam ring 29 _{R in} the circumferential direction without increasing the accuracy of assembly.
Without increasing the terminal and beginning the machining accuracy of the side plate 28 _R and the intake port 37 of the second side plate 30 _R and the discharge port 38 _R, the cam ring 29 _R is to the first side plate 28 _R or the second side plate 30 end of the intake port 37 _R also be displaced in the circumferential direction is present in the range of the suction-side communicating passage 33 ₁ Te,
And if the starting end of the discharge port 38 _R is even present in the range of the discharge-side communication passage 33 _2, the timing of timing or communication is interrupted the pump chamber 34 ₁ is communicated with the suction port 37 _R and the discharge port 38 _R Accurately secure. Thus, the problems described with reference to FIGS. 17C, 17D and 18 can be solved, and the pulsation of the discharge pressure can be prevented.

The invention has been mainly described the structure of the right vane pump P _R, the structure of the left vane pump P _L structure of both a same mirror symmetry of the right vane pump P _R are substantially the same.

FIG. 16 shows the hydraulic coupling.
3 shows a hydraulic circuit of the device H. It is clear from the figure
So, left vane pump P_LSuction port 37_Land
Discharge port 38_LOn the left side of the second side plate 30
Orifice plate 40 provided_LFirst orifice 41
_LAnd the right vane pump P _R
Suction port 37_RAnd discharge port 38_RIs the second rhino
Orifice plate 4 provided on the right side of plate 30
0_RFirst orifice 41_RTo communicate with each other. Ma
Left and right vane pump P_L, P_RSuction port 37_L,
37_RIs a second orifice penetrating the second side plate 30
And the left and right vanes
Pump P_L, P_RDischarge port 38_L, 38_RIs the second
The second orifice 43 penetrating the id plate 30
Communicate with each other.

Left vane pump P_LSuction port 37_LYou
And discharge port 38_LIs the switching valve V_L
Push-up port 28 via₁, 30₁And left oil chamber
50 _LAnd right vane pump P_RSuction port
37_RAnd discharge port 38 _ROf the high pressure side
Luv V_RPush-up port 28 via₁, 30₁And
And right oil chamber 50_RCommunicate with Left vane pump P_LInhalation
Port 37_LAnd discharge port 38_LAny of the low pressure side
Left first side plate 28_LCheck valve 4 provided in
4_LThrough the piston 45_L, 45_RTo the right
Vane pump P _RSuction port 37_RAnd discharge port
38_RIs the right first side plate 28_RTo
Check valve 44 provided_RThrough the piston 45_L,
45_RCommunicate with

Further, the vane lifting port 28₁, 30₁When
Left and right piston 45_L, 45_RBetween relief valve
56_L, 56_RAnd chalk 57_L, 57_RProvided
It is. The relief valve 56_L, 56_RIs virtual
Therefore, the left and right first side plates 28_L, 28_RIs
The first side of the left and right
Plate 28_L, 28_ROr with the second plate 30
Left and right cam rings 29 _L, 29_ROr left and right rotor
32_L, 32_RTo the side clearance that occurs between
It is constituted by. The chalk 57_L, 57_RAlso
Virtual, composed by the side clearance
Is done.

Next, the operation of the embodiment of the present invention having the above configuration will be described.

[0051] In a state where the vehicle V is constant speed running, the first spur gear 2 driving force from the output shaft 1 of the engine E, the second spur gear 3, the front differential 4 and right and left axles 5 _L, 5 the right and left via the _R The power is transmitted to the front wheels W _FL and W _FR . At this time, the third of the front differential 4
The rotation of the spur gear 6 is performed via the fourth spur gear 7, the first bevel gear 8, the second bevel gear 9, the propeller shaft 10, the third bevel gear 11, and the fourth bevel gear 12 through the casing 24 of the hydraulic coupling device H (that is, left and right). cam ring 29 _L, 29 _R) rotating the.
On the other hand, the rotation of the rear wheels W _RL , W _RR driven by the frictional force received from the road surface as the vehicle V travels is rotated by the left and right axles 13 _L ,
13 is transmitted to the rotor 32 _R of the rotor 32 _L and right vane pump P _R of the left vane pump P _L via the rotor shaft 14 _L, 14 _R from _R. Front wheels W _FL, slip is not generated in the W _FR, thus front wheels W _FL, W _FR and the rear wheels W _RL, when the rotational speed of the W _RR are equal, the rotational speed and the left and right of the left and right cam ring 29 _L, 29 _R Rotor 32 _L ,
32 _R and the rotational speed is relative rotation does not occur coincident. As a result, since the left and right vane pumps P _L and P _R do not discharge the hydraulic oil, the hydraulic coupling device H does not transmit the driving force, and the vehicle V enters the front wheel drive state.

When the front wheels W _FL , W _{FR to} which the driving force of the engine E directly acts upon starting or sudden acceleration on a low friction road, the left and right hydraulic pumps P _L interlocked with the rotation of the front wheels W _FL , W _FR. , P _R cam rings 29 _L , 29 _R ,
Relative rotation in the forward direction occurs between the left and right hydraulic pumps P _L , P _R rotors 32 _L , 32 _R interlocked with the rotation of the rear wheels W _RL , W _RR , and the left and right vane pumps P _L , P _R inhales from the suction port 37 _L, 37 _R of the hydraulic oil discharged from the discharge port 38 _L, 38 _R. Discharge port 38 _L , 3
8 first orifice 41 hydraulic fluid discharged from the _R's left and right
_L, 41 through the _R intake port 37 _L, 37 but flows back to the _R, vane pump P of the left and right by the flow resistance at that time
_L, load P _R is generated, the load wheels W _RL of left and right rear as the driving force is transmitted to the W _RR. Thus, the front wheels W _FL , W
_{When the FR} slips, the vehicle is in a four-wheel drive state, and the traction of the vehicle V can be increased. At this time, as the diameter of the first orifices 41 _L , 41 _R decreases, the load on the left and right vane pumps P _L , PR increases, and the rear wheels W _RL , W _R
The driving force transmitted to _RR increases.

When the vehicle V makes a tight turn at low speed,
Left and right front wheels W_FL, W_FRLeft and right than the average radius of the turning trajectory of
Rear wheel W_RL, W_RRThe average radius of the turning trajectory of the
, Front wheel W_FL, W_FRLeft and right cam rings 29 connected to
_L, 29_RAnd rear wheel W_RL, W _RRLeft and right rows connected to
TA 32_L, 32_RAnd a relative rotation occurs. Moreover
Left and right rear wheels W_RL, W_RRThe turning radius of the turning
The relative rotation
The size of the roll is the left and right vane pumps P_L, P_RDifferent in
I have. At this time, the left and right vane pumps P_L, P_RDischarge
Port 38_L, 38_RThe hydraulic oil discharged from the
1 orifice 41_L, 41_RThrough the suction port 37_L,
37_RAnd the left and right vane pumps P_L, P_RBut
The difference between the discharged hydraulic oil is calculated via the second orifice 43.
Both vane pumps P
_L, P_RA large load is prevented from being generated. So
As a result, when the four-wheel drive vehicle V makes a tight turn at low speed
So-called ties, which occur due to the radius difference of the turning locus of each wheel
The corner braking phenomenon can be reduced.

For example, when the left and right front wheels W _FL , W _FR and the right rear wheel W _RR except the left rear wheel W _RL get stuck in mud, the cam ring 29 _L interlocks with the slipping front wheels W _FL , W _FR. , 29 when _R is rotated, also the right rear wheel W _RR friction addicted to muddy is decreased, the vanes 35 ... from the cam ring 29 _R, slip by the drive force transmitted through the rotor 32 _R and the rotor shaft 14 _R Resulting in. However, the left rear wheel W _RL on a road with a high coefficient of friction
Vane 35 from the cam ring 29 _L is in ..., the rotor 32 _L
And the driving force is transmitted through the rotor shaft 14 _L, it is possible to escape from mud by its driving force. That is, according to the hydraulic coupling device H of the present embodiment, the function of a so-called differential limiting mechanism (LSD) can be exhibited. At this time, the second orifice 4
The smaller the diameter of 3, the stronger the differential limiting function.

When the rotation speed of the front wheels W _FL , W _FR exceeds the rotation speed of the rear wheels W _RL , W _RR , such as when starting or suddenly accelerating on a low friction road, the rotors 32 _L , 32 _R. Are relatively rotated in the normal rotation direction (the direction of arrow A in FIG. 3), and FIG.
As shown in the figure, hydraulic oil is sucked from the suction ports 37 _L and 37 _R, and hydraulic oil is discharged from the discharge ports 38 _L and 38 _R. As a result, the high pressure side discharge ports 38 _L , 38 _R
And the low-pressure side suction port 37 _L, 37 switching by the differential pressure between the _R valves V _L, V orifice plate 40 _L of _R, 4
0 _{for R} swings the suction port 37 _L, 37 _R side, the discharge port 38 _L of the high pressure side, 38 _R orifice plate supporting groove 39 _L, 39 via the _R vane push-up port 30 ₁
Communicated with the communication between the vane push-up port 30 ₁ and the low-pressure side of the suction port 37 _L, 37 _R is blocked. And Thus, to urge the vane 35 ... radially outwardly by the hydraulic pressure is transmitted to the vane push-up port 30 _1, it is possible to press the tip on the inner peripheral surface of the cam ring 29 _L, 29 _R.

On the other hand, when the vehicle performs sudden braking, AB
S (anti-lock brake system)
By controlling the locked state, the front wheels W_FL, W_FRAfter
Wheel W _RL, W_RRVehicle behavior by locking earlier than
Is stabilized. Thus, the rear wheel W_RL,
W_RROf front wheel W_FL, W_FRWhen the rotation speed exceeds
Data 32_L, 32_RIn the reverse direction (the direction of arrow B in FIG. 3)
Relative rotation, and as shown in FIG.
8_L, 38_RHydraulic oil is sucked from the suction port 3
7_L, 37_RThe hydraulic oil is discharged from. As a result, high pressure
Side suction port 37 _L, 37_RAnd low pressure side discharge port 3
8_L, 38_RSwitching valve V _L, V_Rof
Orifice plate 40_L, 40_RIs the discharge port 3
8_L, 38_RThe suction port 3 on the high pressure side
7_L, 37_RIs the orifice plate support groove 39_L, 39
_RPush-up port 30 via₁To communicate with
And vane push-up port 30₁And low pressure side discharge port 38
_L, 38_RCommunication with is interrupted. Then, push up the vane
Port 30₁Vane 35 ... by the hydraulic pressure transmitted to
It is urged radially outward and its tip is_L,
29_RCan be pressed into contact with the inner peripheral surface.

Left and right vane pumps P_L, P_RWorks
And the first left and right side plates 28 _L, 28_RDischarge port
Port 38_L…, 38_R... due to the pump discharge pressure
The left and right first side plates 28_L, 28_RIs the axis
The cam rings 29 are pressed outward and_L, 29_RYou
And left and right rotors 32_L, 32_RSide clear between
Lance increases. Also, the first left and right side plates 28
_L, 28_RVane push-up port 28₁, 28₁Act on
The left and right first side play also depends on the pump discharge pressure
G 28_L, 28_RIs pressed outward in the axial direction,
Alance increases. In this way the vane pump
P_L, P_RWhen the side clearance of the high pressure side increases
Hydraulic oil leaks from the pump to the low pressure side, reducing pump efficiency.
There is a problem.

[0058] However, according to this embodiment, by pressing axially the left toward the six bolts 50 ... right spacer 49 and rotate the _R to the left casing 21, the left and right spacers 49 _L, between 49 _R the first side plate 28 of the right and left _L, 28 _R, the second side plate 30, left and right cam ring 29 _L, 29 _R and the left and right rotors 32 _L, 3
2 _R can be held in close contact in the axial direction to reduce side clearance and prevent hydraulic oil leakage.

As described above, 6
By rotating the bolts 50 ... of the vane pump P_L, P_R
Adjust the side clearance of the
Extremely easy. In addition, side clearance
Side clearance
Is adjusted so that the left and right rotors 32_L, 32_RSliding surface of
There is no fear that the frictional resistance of the first member increases. And the bolts 50 ...
Pressing force to the right side plate 28_RWithout acting directly on
Spacer 49_R6 bolts
Even if there is some variation in the pressing force of 50 ...
Plate 28 _RPress with even load to clear side
The lance can be made uniform in the circumferential direction.

By the way, the hydraulic coupling device
In the four-wheel drive vehicle V provided with the_FL, W_FRAnd
And rear wheel W_RL, W_RRLeft and right vanes according to the relative rotational speed difference
Pump P_L, P_RGenerates a load and the front wheel W_FL, W_FRAnd
And rear wheel W_RL, W_RRThe rotation speed is low from the side where the rotation speed is high
The driving force is transmitted to the other side. Therefore, at the time of sudden braking
Front wheel W by controlling braking force_FL, W_FRLet's lock first
Then, the rear wheel W_RL, W_RROf front wheel W_FL, W_FRof
When the number of rotation exceeds the rear wheel W_RL, W_RRFront wheel W from side _FL, W_FR
The driving force is transmitted to the front wheel W_FL, W_FRNo lock
And the rear wheel W_RL, W_RRThe lock is promoted
In the worst case, the front wheel W_FL, W_FRAnd rear wheel W_RL, W_RR
May lock at the same time and cause unstable vehicle behavior.
You.

In order to avoid this, in this embodiment, the front wheel
W_FL, W_FRAnd rear wheel W_RL, W_RRDepending on the direction of relative rotation of
Re vane pump P_L, P_RThe difference in the magnitude of the load
Have. That is, in the low friction road described above,
Front wheel W like when starting or sudden acceleration _FL, W_FRAfter the rotation speed
Wheel W_RL, W_RRIf the number of rotations exceeds
2_L, 32_RAre relatively rotated in the direction of arrow A in FIG.
As shown in (A), the orifice plate 40_L, 40
_RHigh pressure vane lifting port 30₁And low pressure inhalation
Port 37_L, 37_RCommunication was completely cut off
The suction port 37_L, 37_RAnd discharge port 3
8_L, 38_RIs the first orifice 41_L, 41_RJust through
And communicate with the vane pump P_L, P_REmits a heavy load
Raw front wheel W_FL, W_FRFrom rear wheel W_RL, W_RRCommunicated to
The driving force increases (see the solid line in FIG. 14).

On the other hand, when the rotational speeds of the rear wheels W _RL , W _RR exceed the rotational speeds of the front wheels W _FL , W _{FR as in} the case of the above-mentioned rapid braking, the rotors 32 _L , 32 _R are turned by arrows in FIG. rotatable with respect to the direction B, as shown in FIG. 13 (B), the communication between the high pressure vane push-up port 30 ₁ and the low pressure of the discharge port 38 _L, 38 _R is tentatively blocked by the orifice plate 40 _L, 40 _R but since the orifice plate 40 _L, 40 discharge port from the vane push-up port 30 ₁ by the cutout 42 formed in _R 38 _L, 38 _R to the hydraulic oil leaks,
The load generated by the vane pumps P _L , P _R decreases, and the driving force transmitted from the front wheels W _FL , W _FR to the rear wheels W _RL , W _RR decreases (see broken lines in FIG. 14). Thus, at the time of sudden braking, the front wheels W _FL and W _FR are locked prior to the rear wheels W _RL and W _RR , thereby preventing the vehicle behavior from becoming unstable.

[0063] Further, vane pumps P _L, the suction port with the operation of the P _R 37 _L, 37 _R (or the discharge port 3
8 _L , 38 _R ) become negative pressure, the check pressures 44 _L …, 44 _R … open and the suction port 37
_L, 37 since communicating _R (or discharge port 38 _L, 38 _R) on the piston 45 _L, 45 _R, it is possible to reliably prevent the cavitation caused by excessive negative pressure.

As described above, the second orifices 43.
Since the two side plates 30 were drilled,
Hydraulic cup with increased processing accuracy of fiss 43 ...
The operating characteristics of the ring H can be stabilized. Also the
1 orifice 41_L…, 41 _R… And second orifice
43 are concentrated on the second side plate 30
And those orifices 41_L…, 41_R…; 43…
Hydraulic cup with minimum oil passage length
Not only can the ring device H be miniaturized,
An increase in the number of parts can be minimized.

[0065] Moreover the switching valve V _L, the suction port by using a V _R 37 _L, 37 _R and the discharge port 38 _L, 38 _R
It is possible to selectively communicated with the vane push-up port 30 _1, simplification of the reduction and the oil passage of parts is possible as compared to its function in that exert a combination of a plurality of check valves. In particular, the suction port 37 _L , 3
7 _R and a discharge port 38 _L, 38 _R arranged switching valve V _L between, V _R of the orifice plate 40 _L, 40
_Since the first orifices 41 _L and 41 _R are formed using _R , the length of the oil passage can be reduced to a minimum.

Further, since the left and right vane pumps P _L and P _R share the second side plate 30, the number of parts can be reduced.

Although the embodiments of the present invention have been described in detail, various design changes can be made in the present invention without departing from the gist thereof.

For example, in the embodiment, the vane pumps P _L and P _R of the hydraulic coupling device H have been exemplified.
The present invention can be applied to a vane pump for any other use.

In the embodiment, the cam ring 29_L, 29_R
First side plate 28_L, 28 _ROn the side facing
Suction side communication passage 33₁And discharge side communication passage 33_TwoForm
However, the side facing the second side plate 30
Or the first side plate 28_L, 28_RAnd the second
Suction-side communication passages on both sides facing the id plate 30
33₁And discharge side communication passage 33_TwoMay be formed. Ma
Cam ring 29_L, 29_ROn the side of the suction side communication passage 33
₁And discharge side communication passage 33_TwoInstead of forming a cam
Ring 29_L, 29_RBy digging a groove in the inner peripheral surface of
Entry side communication passage 33 ₁And discharge side communication passage 33_TwoForm
be able to.

In the embodiment, the first side plate 2
8 _L , 28 _R and the second side plate 30 and the cam rings 29 _L , 29 _R are prevented from rotating by spline fittings 31.
The first side plate 2
8 _L, 28 _R and the second side plate 30 and the cam ring 29 _L, 29 to perform a _R a linear shaft extending in the axial direction is also possible, according to the present invention either case, the first side plate 28 _L, 28 circumferential positioning accuracy of the _R and the second side plate 30 and the cam ring 29 _L, 29 _R is not particularly necessary to increase.

[0071]

As described above, according to the first aspect of the present invention, a communication passage is formed in the suction cam portion and the discharge cam portion of the cam ring so as to allow the hydraulic oil to escape in the circumferential direction across the vane. The end of the communication passage of the suction cam portion is a substantial end of the suction port, and the beginning of the communication passage of the discharge cam portion is a substantial start of the discharge port. Since the communication passage is formed in the cam ring in which the suction cam portion and the discharge cam portion are formed, even if the side plate in which the suction port and the discharge port are formed is out of phase with respect to the cam ring, the suction cam portion and the side plate correspond to each other. There is no danger that the positional relationship between the communication passage and the discharge cam portion and the corresponding communication passage will be shifted. Therefore, the end of the suction port is located on the delay side in the rotor rotation direction from the end of the communication passage corresponding to the suction cam portion, and the start end of the discharge port is in the rotor rotation direction more than the start end of the communication passage corresponding to the discharge cam portion. If there is some error in the phase between the side plate and the cam ring, the timing difference at the moment when the pump chamber separates from the suction port and the timing at the moment when the pump chamber communicates with the discharge port is provided. Pulsation of the pump discharge pressure can be prevented.

According to the invention described in claim 2,
Since the communication passage is formed by chamfering the side walls of the suction cam portion and the discharge cam portion of the cam ring, machining of the communication passage is facilitated.

[Brief description of the drawings]

FIG. 1 is a skeleton diagram of a power transmission device of a four-wheel drive vehicle.

FIG. 2 is a longitudinal sectional view of a hydraulic coupling device.

FIG. 3 is a sectional view taken along line 3-3 in FIG. 2;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 2;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 2;

FIG. 6 is a sectional view taken along line 6-6 in FIG. 2;

FIG. 7 is an enlarged view of a main part of FIG. 2;

8 is a sectional view taken along line 8-8 in FIG. 7;

FIG. 9 is a perspective view of a coil spring.

FIG. 10 is a perspective view of an orifice plate.

FIG. 11 is an enlarged view of a main part of FIG. 3;

FIG. 12 is a sectional view taken along line 12-12 of FIG. 11;

FIG. 13 is a diagram illustrating the operation of an orifice plate.

FIG. 14 is a graph illustrating the operation of an orifice plate.

FIG. 15 is an enlarged sectional view taken along line 15-15 of FIG. 5;

FIG. 16 is a hydraulic circuit diagram of a hydraulic coupling device.

FIG. 17 is an explanatory view of a conventional vane pump.

FIG. 18 is an explanatory view of a conventional vane pump.

[Explanation of symbols]

28 _L 1st side plate (side plate) 28 _R 1st side plate (side plate) 29 _L cam ring 29 _R cam ring 29 ₁ suction cam section 29 ₂ discharge cam section 30 2nd side plate (side plate) 32 _L rotor 32 _R Rotor 32 ₁ Vane groove 33 ₁ First communication path (communication path) 33 ₂ First communication path (communication path) 34 ₁ Pump chamber 35 Vane 37 _L suction port 37 _R suction port 38 _L discharge port 38 _R discharge port

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takuya Kurokawa 19, Matsuyamacho, Moka-shi, Tochigi Prefecture Honda Motor Co., Ltd.Tochigi Seisakusho Co., Ltd. (72) Inventor Takeshi Mochizuki 19 Matsuyamacho, Moka-shi, Tochigi Pref. F term (reference) 3H040 AA03 BB05 BB11 CC10 CC16 DD03 DD06 DD11 DD16 DD23 DD24 DD28 DD40

Claims (2)

[Claims] The suction cam portion (29) is provided on the inner peripheral surface.₁) And vomit
Outgoing cam (29_Two) Formed cam ring (29)_L, 2
9_R) And cam ring (29_L, 29_R) Rotatably stored inside
Rotor (32_L, 32_R) And cam ring (29_L, 29_R) And rotor (32_L,
32_R) Side plates (28)_L, 28
_R, 30) and the rotor (32)_L, 32_R).
Groove (32₁) Is slidably supported at the radial outer end
Is a cam ring (29_L, 29_R) In contact with the inner peripheral surface
Number of vanes (35), two adjacent vanes (35), cam ring (29)_L,
29_R) And rotor (32_L, 32_R)
The rotor (32_L, 32_R) With rotation
Pump room that expands and contracts (34₁) And the suction cam portion (29)₁Side plate to face)
(28_L, 28_R) Formed in the suction port (37_L, 3
7_R) And the discharge cam portion (29)_TwoSide plate to face)
(28_L, 28_R) Formed in the discharge port (38)._L, 3
8_R), And the suction port (37_L, 37_RPon) whose volume increases from)
Room (34₁) The volume of hydraulic oil sucked in) is reduced.
Room (34₁) To the discharge port (38_L, 38 _R) To vomit
The cam ring (29_L, 29_R) Suction cam (29)₁)
And the discharge cam section (29_Two), Straddling the vane (35)
Communication passage (33) to allow hydraulic oil to escape in the circumferential direction₁, 33_Two)
A vane pump characterized by forming: 2. A suction cam portion of the cam ring (29 _L, 29 _R) in that the formation (29 ₁₎ and said communication passage by chamfering the side walls of the discharge cam (29 ₂₎ (33 _1, 33 ₂₎ The vane pump according to claim 1, characterized in that: