JPH07279603A - Volume type fluid machine - Google Patents

Abstract

PURPOSE:To improve durability by dispensing with the bearing of a rotor in a volume type fluid machine like a hydraulic pump and a hydraulic motor, etc. CONSTITUTION:A cylinder 7 fixed inside of a main casing 1 is provided with an operation room forming space 11 in a nearly regular triangle shape and three operation rooms volumes are expanded/shrunk are partitioned between the cylinder 7 and a rotor 13 by fitting a simulated oval column shaped rotor 13 in this operation room forming space 11, eccentrically rotatably. Intake ports 141, 142 and exhaust ports 151, 152 which are able to communicate with three operation rooms are formed in a pair of side plates 14, 15 fixed on the rotor 13 in one body and making sliding contact with both side surfaces of the cylinder 7. The rotor 13 and both side plates 14, 15 are driven by a motor through magnetic couplings 21, 22.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positive displacement fluid machine used for fluid pressure pumps, fluid pressure motors, various engines, flow meters and the like.

[0002]

2. Description of the Related Art Among conventional displacement type fluid machines, rotary pumps having a rotor are known, for example, trochoid pumps, gear pumps, vane pumps, roots pumps, scroll pumps, etc., and these pumps operate in their working chambers. By supplying fluid, it also functions as a motor.

[0003]

By the way, when the conventional displacement type fluid machine is used by being immersed in a working fluid,
The bearing that supports the rotor will come into contact with the fluid. At this time, when the fluid is water, acid, alkali, etc., corrosion occurs, and there is a problem that a metal bearing such as a ball bearing cannot be used. Therefore, if a bearing made of a corrosion resistant resin is used, there is a problem that sufficient performance cannot be obtained in terms of wear resistance.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a positive displacement fluid machine which does not require a bearing of a rotor and is excellent in durability.

[0005]

In order to achieve the above object, a positive displacement fluid machine according to a first aspect of the present invention has a housing and a working chamber forming space having a substantially equilateral triangle shape inside the housing. A fixed cylinder; a rotor that eccentrically rotates while contacting the inner peripheral wall of the working chamber forming space at three points; a suction side plate that slides in contact with one side wall of the cylinder and rotates eccentrically with the rotor; Three parts that are defined by a discharge side plate that slides in contact with the other side wall and rotates eccentrically with the rotor integrally, and a cylinder, a rotor, a suction side plate, and a discharge side plate, the volume of which expands and contracts as the rotor rotates. Working chamber, a suction port communicating with the working chamber formed in the suction side side plate to increase the volume, and a working chamber formed in the discharge side side plate to reduce the volume Characterized by comprising a discharge port communicating with the.

Further, in the displacement type fluid machine according to a second aspect, in addition to the configuration of the first aspect, the rotor has a pair of small-diameter portion cylindrical walls located at both ends in the longitudinal direction, and the pair of small-diameter portions. It is characterized by a pseudo elliptic cylinder shape having a pair of large-diameter partial cylindrical walls that connect the cylindrical walls to each other.

Further, in the displacement type fluid machine according to a third aspect, in addition to the structure of the first aspect, the suction side plate or the discharge side plate is connected to the input shaft or the output shaft via a magnetic coupling rig. It is characterized by

In addition to the structure of claim 1, a positive displacement fluid machine according to a fourth aspect of the present invention is such that the suction side plate is disposed in a suction chamber formed in the housing, and the volume is increased. And the suction chamber communicate with each other through a suction port.

According to a fifth aspect of the displacement type fluid machine, in addition to the structure of the first aspect, the discharge side side plate is disposed in a discharge chamber formed in the housing, and the volume of the working chamber is reduced. And the discharge chamber communicate with each other through the discharge port.

According to a sixth aspect of the displacement type fluid machine, in addition to the structure of the first aspect, the suction side plate or the discharge side plate is connected to the input shaft or the output shaft via an eccentric coupling. It is characterized by

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 6 show an embodiment in which the present invention is applied to a hydraulic pump. FIG. 1 is an exploded perspective view of the hydraulic pump, and FIG. 2 is a vertical sectional view of the hydraulic pump (2-2 in FIG. 3). 2), FIG. 3 is a sectional view taken along line 3-3 of FIG. 2, FIG. 4 is a diagram corresponding to FIG. 3 in which the phases of the rotors are different, FIG. 5 is an explanatory diagram of the action, and FIG. It is a graph which shows.

As shown in FIGS. 1 to 3, the hydraulic pump P includes a main housing 1 having a substantially cylindrical shape, a cover 3 which is connected to an opening of one end of the main housing 1 by a bolt 2a.
The main housing 1 is provided with an opening at the other end and a sub-housing 5 which is coupled with bolts 2b ... The joint between the main housing 1 and the cover 3 is an O-ring 6a
Sealed by the main housing 1 and the partition 4
The joint portion with and is sealed by the O-ring 6b. A cylinder 7 is fitted inside the main housing 1 through an O-ring 6c, and is fixed by a key 8 so as not to rotate.
With the suction chamber 9 communicating with the intake port 1 ₁ formed on the outer periphery of the main housing 1 is defined between the cylinder 7 and the partition wall 4, the outer periphery of the main housing 1 between the cylinder 7 and the cover 3 Discharge chamber 1 connected to the formed discharge port 1 ₂
0 is defined.

The cylinder 7 is a member having a short cylindrical shape, and the working chamber forming space 1 is formed so as to penetrate the central portion thereof.
1 smoothly connects the three plane walls A, A, A forming part of the three sides of the equilateral triangle and the plane walls A, A, A at positions corresponding to the vertices of the equilateral triangle. It is defined by three partial cylindrical walls B, B, B. At the central portion of each of the partial cylindrical walls B, B, B, three communicating portions 12 ₁ , 12 ₂ , 12 _{3 that} are continuous with the working chamber forming space 11 are continuously provided so as to extend radially outward.

A pseudo elliptic cylinder-shaped rotor 13 is eccentrically fitted into the working chamber forming space 11 of the cylinder 7 so as to be eccentrically rotatable. A disk-shaped suction side plate 14 housed in the suction chamber 9 and a disk-shaped discharge side plate 15 housed in the discharge chamber 10 are overlapped on both side surfaces of the rotor 13 The bolts 16 and 16 are joined together. The thickness of the rotor 13 in the axial direction is substantially the same as the thickness of the cylinder 7 in the axial direction.
With the rotation of 5, the inner wall surface of the suction side plate 14 is in liquid-tight contact with one outer wall surface of the cylinder 7, and the inner wall surface of the discharge side plate 15 is liquid-tight in the other outer wall surface of the cylinder 7. Slide on.

As is apparent from FIG. 3, the rotor 13 has a pseudo elliptic cylindrical shape, and its peripheral wall has a pair of small-diameter partial cylindrical walls C formed so as to face each other at both longitudinal ends.
It is configured by smoothly connecting C and another pair of large-diameter partial cylindrical walls D, D formed so as to face each other. The radius of curvature of the small-diameter partial cylindrical walls C, C is the same as the radius of curvature of the partial cylindrical walls B, B, B of the working chamber forming space 11 of the cylinder 7, and Is also small.

The outer circumference of the rotor 13 and the inner circumference of the cylinder 7 are always in contact with each other at three points, whereby three independent working chambers 17 ₁ , 1 are provided between the rotor 13 and the cylinder 7.
7 ₂ and 17 ₃ are defined. Each working chamber 17 ₁ , 17 ₂ ,
17 ₃ is the corresponding communicating portion 12 ₁ , 12 ₂ , 1
Constantly communicating with the 2 _3.

As is apparent from FIG. 3, the central axis O'of the rotor 13 is eccentric to the central axis O of the cylinder 7 by δ. As is clear from comparing FIGS. 3 and 4, when the rotor 13 rotates clockwise, the central axis O ′ of the rotor 13 rotates counterclockwise around the central axis O of the cylinder 7. Thus, when the rotor 13 rotates 360 ° in the clockwise direction, the locus of the central axis O ′ rotates 360 ° in the counterclockwise direction about the central axis O of the cylinder 7.

In FIG. 4, the small diameter partial cylindrical wall C of the rotor 13 is fitted to the lower right partial cylindrical wall B of the cylinder 7, and therefore the volume of the working chamber 17 ₂ becomes the minimum (that is, zero). . On the other hand, in FIG. 3, the large-diameter partial cylindrical wall D of the rotor 13 faces the partial cylindrical wall B on the upper side of the cylinder 7, so that the working chamber 17 ₁ has the maximum volume. Thus, for each rotation of the rotor 13, each working chamber 17 ₁ , 1
The volumes of 7 ₂ and 17 ₃ increase and decrease twice (for example, minimum → maximum →
Min → max → min).

A pair of suction ports 14 ₁ and 14 ₂ are formed on the suction side plate 14 so as to face each other in diameter. A pair of discharge ports 15 ₁ and 15 ₂ are formed on the discharge side plate 15 so as to face each other in diameter. The respective intake ports 14 ₁ and 14 ₂ and the exhaust ports 15 ₁ and 15 ₂ have a central angle slightly smaller than 90 °, and are arranged alternately in different phases so as not to overlap each other. It The intake port 14 ₁ and the exhaust port 15 ₂ are located on one side of an extension line of the major axis of the rotor 13, and the intake port 14 ₂ and the exhaust port 1
5 ₁ is located on the other side of the extension line of the long diameter of the rotor 13.

The rotor 13 rotates to rotate the working chamber 17₁, 17
₂, 17₃When the volume of the₁，
17₂, 17₃Is a suction side support that rotates together with the rotor 13.
The suction port 14 of any of the id plates 14₁, 14₂
To the communication part 12₁, 12₂, 12₃And communicate via
Room 17₁, 17₂, 17₃When the volume of
Working chamber 17₁, 17₂, 17₃Turns together with the rotor 13
One of the discharge ports of the discharge side plate 15 that rolls
15₁, 15₂To the communication part 12₁, 12₂, 12 ₃Through
Communicate with each other. And the working chamber 17₁, 17₂, 17₃The content of
Only when the product becomes maximum and when the product becomes minimum
17₁, 17₂, 17₃Is the intake port 14₁, 14₂Over
And discharge port 15₁, 15₂Cut off from.

When the rotor 13 rotates as described above, the pair of large-diameter partial cylindrical walls D, D of the rotor 13 make rolling contact with the three plane walls A, A, A of the cylinder 7. The wear of the contact part is extremely small. In addition, the pair of small-diameter partial cylindrical walls C, C of the rotor 13
Is in sliding contact with the three plane walls A, A, A of the cylinder 7 in a straight line along the generatrix of the small diameter partial cylindrical wall C, C, but the three partial cylindrical walls B, B, C of the cylinder 7 are Since it makes a sliding contact with B on an arcuate surface rather than a straight line, wear of the contact portion is significantly reduced.

A rotary shaft 19 of a motor 18 which is connected to the sub-housing 5 with bolts 2c is arranged coaxially with a central axis O of the cylinder 7, and the rotary shaft 19 has a magnet which rotates inside the sub-housing 5. The support member 20 is fixed. A plurality of magnets 21, ..., 22 are respectively provided on the magnet supporting member 20 and the suction side plate 14 that faces the magnet supporting member 20 with the partition wall 4 interposed therebetween. Therefore, when the motor 18 is driven to rotate the magnet support member 20, the suction side plate 14 causes the suction side plate 14 to move due to the attraction force acting between the magnets 21.
3 and the discharge side plate 15 rotate integrally. The magnets 21 ... 22 constitute the magnetic coupling of the present invention.

Since the torque of the motor 18 is transmitted from one side of the partition wall 4 to the other side through the magnets 21, ..., 22, the rotating shaft 19 of the motor 18 penetrates through the partition wall 4 to directly rotate the rotor. The seal member required when driving 13 is unnecessary. As a result, there is no risk of oil leaking to the motor 18 side through the partition wall 4, and maintenance of the seal member becomes unnecessary, which reduces running costs.

Further, the rotor 13 and both side plates 1
When the rotors 4, 15 rotate integrally, the rotor 13 contacts and guides the inner peripheral wall of the working chamber forming space 11 of the cylinder 7 at three points, so that a special bearing for supporting the rotor 13 is unnecessary. Become. As a result, the problems of durability deterioration due to rust and wear that occur when a bearing is used can be solved all at once.

Next, the operation of the embodiment of the present invention having the above construction will be described. Incidentally, the three working chambers 17 ₁ , 1
Since 7 ₂ and 17 ₃ have the same functions but different phases, the working chamber 17 ₁ will be described as a representative example.

In the state of FIG. 5A, the working chamber 17₁The content of
Product is maximum and working chamber 17₁Is the intake port 14₂
And discharge port 15₁Has been cut off from. This state
The rotor 13 and both side plates 14 and 15 are clockwise
When rotated in the direction, the working chamber 17 ₁Is the communication part 12₁Through
Immediately discharge port 15₁To communicate with the working chamber 1
7₁Volume begins to decrease. As a result, Fig. 5 (A) →
In the process of (B) → (C) → (D), the working chamber 17₁Push
The discharged oil is the communication part 12₁, Discharge port 15₁,
Outlet 1 through outlet chamber 10₂Emitted from. That
Then, the rotor 13 rotates 90 ° and the state shown in FIG.
Then, the working chamber 17₁Has a minimum (ie, zero) volume
And working chamber 17₁Is the intake port 14₁And discharge port
To 15₁Cut off from.

When the rotor 13 further rotates clockwise from the state of FIG. 5 (D), the working chamber 17 ₁ immediately communicates with the suction port 14 ₁ via the communicating portion 12 ₁ , and the volume of the working chamber 17 ₁ is increased. Begins to increase. As a result,
In the process of (D) → (E) → (F) → (A), the suction port 1 ₁
The oil sucked from the suction chamber 9, the suction port 14 ₁ ,
It is sucked into the working chamber 17 ₁ via the communication portion 12 ₁ . Then, when the rotor 13 rotates 180 ° and enters the state of FIG. 5 (A), the volume of the working chamber 17 ₁ becomes maximum and returns to the initial state.

As described above, the rotor 13 is rotated by 180 °.
While rotating, the working chamber 17 ₁ performs one cycle of suction and discharge, and when the rotor 13 further rotates 180 ° thereafter, the working chamber 17 ₁ similarly performs another cycle of suction and discharge. That is, the working chamber 17 ₁ is ₁ of the rotor 13.
Two cycles of suction and discharge are performed for each rotation.

The working chamber 17 ₁ has been described above.
The remaining two working chambers 17 ₂ and 17 ₃ are also the working chambers 17 ₁
The same operation as is done. However, three working chambers 1
7 ₁ , 17 ₂ and 17 ₃ have phases of intake and discharge of 12
Since the hydraulic pump P is displaced by 0 °, suction and discharge are performed 6 times per rotation of the rotor 13 with a phase difference of 60 °.

This will be described with reference to FIG.
P _{1 in} (A) is the working chamber 17 with respect to the rotation angle of the rotor 13.
₁ shows the pressure change of ₁ , and P _{2 which} is 120 ° out of phase with P ₁ shows the pressure change of the working chamber 17 ₂ , and P _{3 which} is 120 ° out of phase with P ₂ shows the pressure of the working chamber 17 ₃ . The changes are shown respectively. Thus, the change in the discharge pressure of the hydraulic pump P causes six pressure peaks per one rotation of the rotor 13 as shown in FIG. 6 (B), which can reduce the pulsation of the discharge pressure as a whole. This makes it possible to reduce the load on the motor 18 and reduce the power consumption.

When the present invention is applied to a fluid pressure motor or an internal combustion engine, the pulsation of the output torque can be reduced due to the above reason.

Along with the rotation of the rotor 13, the intake side side pump is
The rate 14 and the discharge side plate 15 also rotate integrally
The suction port formed on the suction side plate 14
14₁, 14₂Position and discharge side plate 1
Discharge port 15 formed in 5 ₁, 15₂The position of
Turn into. However, the suction side plate 14 does not
Since it is stored inside the entrance 9, the suction port 1
Four₁, 14₂The suction port 14 even if the position of the₁，
14₂Can always suck oil from the suction chamber 9.
And the discharge side plate 15 is inside the discharge chamber 10.
It is stored in the outlet port 15₁, 15₂Place of
Even if the position is changed, the discharge port 15₁, 15₂Is always discharged
The oil can be discharged into the chamber 10.

Furthermore, the amount of oil discharged from each working chamber 17 ₁ , 17 ₂ , 17 ₃ in one cycle is
Since it is uniquely determined by the difference between the maximum value and the minimum value of the volumes 7 ₁ , 17 ₂ and 17 ₃ , the rotation speed of the rotor 13,
That is, the discharge amount of the oil pump P can be controlled based on the number of rotations of the motor 18, and it can be used as a metering pump.

FIG. 9 shows a second embodiment of the present invention.

The hydraulic pump P of the second embodiment employs an Oldham coupling 23 so as to allow eccentric rotation of the rotor 13 in place of the magnetic coupling rigs (magnets 21 ... 22 ...) of the first embodiment. The rotary shaft 19 of the motor 18 penetrating the partition wall 4 via the seal member 24 and the suction side plate 14 are connected via the Oldham coupling 23. The Oldham cup rig 33 constitutes the eccentric coupling of the present invention.

Thus, the same working effect as that of the first embodiment can be obtained by the second embodiment.

Although the embodiments of the present invention have been described above in detail, the present invention is not limited to the above embodiments, and various design changes can be made.

For example, although the oil pump P which is a pump for incompressible fluid is illustrated in the embodiment, the positive displacement fluid machine of the present invention can be used for various applications other than the oil pump P. That is, a compressor, a blower, a pump for a compressible fluid such as a vacuum pump, a motor for an incompressible fluid, a motor for a compressible fluid, an internal combustion engine such as a gasoline engine, an external combustion engine such as a steam engine, a hydrogen engine, a Stirling engine. Alternatively, it can be applied to a flow meter. Further, if a canned motor that is liquid-tightly sealed is adopted instead of the ordinary motor 18, the hydraulic pump P can be used by being immersed in the liquid together with the canned motor.

[0040]

As described above, according to the first aspect of the present invention, the rotor is housed in the substantially equilateral triangular working chamber forming space formed in the cylinder, and the rotor is housed in the working chamber forming space. By eccentrically rotating while contacting the peripheral wall at three points, the volume of the three working chambers is expanded and contracted, so bearings for supporting the rotor are not required, and durability deterioration due to bearing rust and wear is eliminated. To be done. Further, since the volume of the working chamber is expanded and contracted six times in total for one rotation of the rotor, the pulsation of the discharge pressure is reduced in the fluid pressure pump, and the pulsation of the output torque is reduced in the fluid pressure motor and the internal combustion engine.

According to the invention described in claim 2,
Since the shape of the rotor is a pseudo elliptic cylinder shape in which a small-diameter partial cylindrical wall and a large-diameter partial cylindrical wall are combined, the rotor and the inner peripheral wall of the working chamber forming space are surely brought into contact with each other at three points, and the contact portion is worn. And can prevent pressure leakage.

According to the invention described in claim 3,
Since the suction side plate or the discharge side plate is connected to the input shaft or the output shaft via the magnetic coupling, the rotor can be eccentrically rotated while preventing pressure leakage from the housing.

According to the invention described in claim 4,
Since the suction side plate is disposed in the suction chamber formed in the housing and the working chamber and the suction chamber are communicated with each other through the suction port, the suction side plate having the suction port rotates integrally with the rotor. Also can reliably supply the fluid to the working chamber.

According to the invention described in claim 5,
Since the discharge side plate is arranged in the discharge chamber formed in the housing and the working chamber and the discharge chamber are communicated with each other through the discharge port, the discharge side plate having the discharge port rotates integrally with the rotor. Can reliably discharge the fluid from the working chamber.

According to the invention described in claim 6,
Since the suction side plate or the discharge side plate is connected to the input shaft or the output shaft via the eccentric coupling rig, the rotor can be freely eccentrically rotated to transmit power to the rotor or extract power from the rotor. .

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a hydraulic pump

FIG. 2 is a vertical sectional view of a hydraulic pump (a sectional view taken along line 2-2 of FIG. 3).

3 is a sectional view taken along line 3-3 of FIG.

FIG. 4 is a diagram in which the phases of the rotor corresponding to FIG. 3 are changed.

FIG. 5 is an explanatory diagram of operation

FIG. 6 is a graph showing discharge pressure pulsation.

FIG. 7 is a longitudinal sectional view of a hydraulic pump corresponding to FIG. 2 according to a second embodiment of the present invention.

[Explanation of symbols]

1 Main Housing (Housing) 7 Cylinder 9 Suction Chamber 10 Discharge Chamber 11 Working Chamber Forming Space 13 Rotor 14 Suction Side Plate 14 ₁ , 14 ₂ Suction Port 15 Discharge Side Plate 15 ₁ , 15 ₂ Discharge Port 17 ₁ , 17 ₂ , 17 ₃ Working chamber 19 Rotating shaft (input shaft) 21 Magnet (magnetic coupling rig) 22 Magnet (magnetic coupling rig) 23 Oldham coupling (eccentric coupling) C Small diameter partial cylindrical wall D Large diameter partial cylindrical wall

Claims (6)

[Claims] 1. A housing (1), a cylinder (7) fixed to the inside of the housing (1) having a working chamber forming space (11) having a substantially equilateral triangle shape, and a working chamber forming space (11). A rotor (13) that eccentrically rotates while contacting the inner peripheral wall of the rotor at three points, and a rotor (13) slidingly contacting one side wall of the cylinder (7).
Suction side plate (14) that rotates eccentrically with
And the rotor (13) by sliding contact with the other side wall of the cylinder (7).
Discharge side plate (15) that rotates eccentrically together with
And three working chambers defined by the cylinder (7), the rotor (13), the suction side plate (14), and the discharge side plate (15), the volume of which expands and contracts as the rotor (13) rotates. (17 _1, 17 _2, 17 ₃₎ and, the suction-side side plate (14) is formed by working chambers expanding volume (17 _1, 17 _2, 17 ₃₎ the suction port (14 ₁ communicating with, 14 ₂ ) And a discharge port (15 ₁ , 15 ₂ ) communicating with the working chamber (17 ₁ , 17 ₂ , 17 ₃ ) formed in the discharge side plate (15) and having a reduced volume. Positive displacement fluid machine. 2. A rotor (13) has a pair of small-diameter partial cylindrical walls (C) located at both longitudinal ends thereof and a pair of large-diameter partial cylindrical walls (C) interconnecting the pair of small-diameter partial cylindrical walls (C). The displacement type fluid machine according to claim 1, wherein the displacement type fluid machine has a pseudo elliptic cylinder shape having a cylindrical wall (D). 3. The suction side plate (14) or the discharge side plate (15) is attached to the magnetic coupling rig (2).
2. A displacement type fluid machine according to claim 1, wherein the displacement type fluid machine is connected to an input shaft (19) or an output shaft via (1, 22). 4. A working chamber (17 ₁ , 17 ₂ , 17 ₃ ) in which the suction side plate (14) is disposed in a suction chamber (9) formed in the housing (1) and the volume of which expands.
The positive displacement fluid machine according to claim 1, wherein the suction chamber (9) and the suction chamber (9) communicate with each other through a suction port (14 ₁ , 14 ₂ ). 5. A working chamber (17 ₁ , 17 ₂ , 17 ₃ ) in which the discharge side plate (15) is arranged in a discharge chamber (10) formed in the housing (1) and the volume of which is reduced.
The positive displacement fluid machine according to claim 1, wherein the discharge chamber (10) and the discharge chamber (10) communicate with each other through the discharge ports (15 ₁ , 15 ₂ ). 6. The intake side plate (14) or the discharge side plate (15) is attached to the eccentric cup rig (2).
The positive displacement fluid machine according to claim 1, wherein the positive displacement fluid machine is connected to the input shaft (19) or the output shaft via 3).