JPS5934492A - Eccentric pump - Google Patents

Abstract

PURPOSE:To provide a simple seal member to lessen the pulsation of discharged fluid by giving eccentric motion to an eccentric ring to generate a pumping action without rotating a pump shaft. CONSTITUTION:While a spherical body 35 of a spherical bearing 34 rotates eccentrically when a motor shaft 8 rotates, a socket 33 is not rotated since the revolution of a pump shaft 10 on its own axis is restrained by a rotation stopper 44, and only the eccentric motion of the spherical body 35 is transmitted so that eccentric rings 16, 17 move eccentrically about the center O of a center bearing 11. When contact portions of the outer peripheral surface of the eccentric ring 16 and the inner peripheral surface of a hollow chamber A move counterclockwise along with said eccentric motion, the volume of a suction chamber Pi divided by a partition member 21 increases and the volume of a discharge chamber Po decreases. Thus, fluid introduced through a suction port 26 and a suction path 24 is pressurized and discharged to a discharge path 25. The eccentric ring 17 side pumping action generates just 180 deg. of phase difference so that the pulsation of fluid is cancelled by each other. A diaphragm 43 ensures the sealing property of the hollow chamber A.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an eccentric pump in which a pumping action is performed by an eccentric wheel that moves eccentrically with respect to a cylindrical pump chamber.

Generally, in this type of eccentric pump, the eccentric wheel is caused to perform eccentric movement by rotating the pump shaft. Therefore, it is necessary to provide a sealing member that prevents fluid from leaking from the pump chamber between a rotating part such as a pump shaft and a fixed part such as a pump casing. Such a sealing member is not only expensive, but also makes it difficult to completely seal the pump chamber.

Furthermore, in an eccentric pump using a single eccentric wheel, it is impossible to avoid pulsation in the discharged fluid.

Therefore, in order to reduce this pulsation, it is conceivable to provide multiple eccentric wheels so that the pumping action is performed by shifting the phase from each other. A seal part is required to seal the gap.

If the pump shaft rotates, a sealing member for this purpose is required to seal between the rotating part and the fixed part.

Therefore, the main object of the present invention is to obtain an eccentric pump that allows the eccentric ring to perform eccentric movement without rotating the pump shaft, thereby completely sealing the pump chamber using a simple sealing member. purpose.

Another object of the present invention is to make two eccentric wheels eccentrically move with a phase difference of 180 degrees, and to discharge the fluid discharged from each pump chamber through a common discharge passage, thereby increasing the discharge fluid as a whole. The objective is to obtain an eccentric pump with reduced pulsation.

In order to achieve these objects, in the present invention, the middle part of the pump shaft which is stopped from rotating is supported by a swingable IC 7, and one end of the pump shaft is eccentrically driven by a motor, thereby making it possible to swing the pump shaft. The eccentric wheels provided on both sides of the swinging support section move eccentrically with a phase difference of 180 degrees from each other. A partition means is provided for fluid-tightly partitioning each pump chamber in the circumferential direction between the outer circumferential surface of these eccentric wheels and the inner circumferential surface of a cylindrical hollow chamber formed in the pump casing. Each suction chamber and each discharge chamber defined on both sides of the means communicate with a common suction passage and a common discharge passage, respectively.

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

The pump casing C is constructed by integrally connecting a cylindrical casing body 1 and a side wall 2 that closes an opening at one end of the body 1 with bolts 3 . A disk-shaped gasket 4 is provided between the main body 1 and the side wall 2 to prevent fluid from leaking between the gaskets 4 and 4. The other end of the main body 1 of the pump casing C is fixed to the motor casing 6 with bolts 5. A packing γ is also provided between these to prevent fluid leakage.

Inside the pump casing C, a cylindrical hollow chamber A having the same center axis XX as the rotational axis of the motor shaft 80 is provided. An annular bearing support member 9 is fitted and fixed in the center of the hollow chamber A. An outer ring 12 of a central bearing 11 attached to the intermediate portion of the pump shaft 10 is fitted into the support member 9 and fixed by a collar 13. This bearing 11 has a center axis X
It has a spherical surface centered on a point O on -X, thereby forming a spherical support portion that supports the pump shaft 10 so as to be swingable around the point O.

6 - The pump shaft 1oVC has spherical bearings 14.15 fixed to each side of the center bearing 110, and an eccentric ring 16.1γ is fitted to the outer periphery of each of these spherical bearings 14.15, and a collar 18. It is held fixed by 19. The outer diameter of these eccentrics 16.1γ is smaller than the inner diameter of the hollow chamber A, and when the pump shaft 10 swings around point O, one point on the outer circumferential surface of the eccentrics 16,1t touches the inner circumference of the hollow chamber Δ. Crescent-shaped pump chambers pl, pr (second
(see figure) are formed respectively.

The eccentric wheels 16, 1γ and the bearing support member 9 are provided with a radial groove 20, as shown in FIG. has been done. This partition member 21 is integrally attached to the casing body 1, and fluid-tightly divides each pump chamber pl, pr between the eccentric wheels 16, 1γ and the casing body 1 in the circumferential direction. Suction chamber P on both sides
t and a discharge chamber J) O. Also, eccentric wheel 1
6° 11 is slidable on this partition member 21 and is also swingable around the cylindrical surface of the partition member 21, that is, within a plane perpendicular to the central axis XX. There is.

As shown in FIG. 2, the casing body 1 has openings 2 communicating with the suction chambers P of the pump chambers PL and PR, respectively.
2 and the discharge chamber PO of each pump chamber Pl, pr are provided with openings 23 that communicate with each other, and these openings 22 and 23 communicate with each other through a common suction passage 24 and a discharge passage 25, respectively, as shown in FIG. As shown, it communicates with the suction port 26 and the discharge port 2γ. A suction pipe and a discharge pipe (not shown) are connected to the suction port 26 and the discharge port 2γ, respectively.

Holding members 28 and 29 are provided on both sides of the hollow chamber A,
The pressing members 28, 29 press the gaskets 30, 30, . . In order to maintain this pressing force appropriately and ensure smooth movement of the eccentric wheels 16, 1γ, the side wall 2
A pressurizing screw 31 is provided in the holder 4 so that the pressing force against the pressing member 28 can be adjusted by passing it through the packing 4. Further, the holding member 28.29 is prevented from rotating around the central axis XX by a rotation stopper 32.32.

A socket portion 33 is provided at the motor side end of the pump shaft 10, and a spherical bearing 3 is installed inside this socket portion 33.
4 is installed. A cylindrical opening 36 passing through the center of the sphere 35, which is the inner ring of the spherical bearing 34, is provided. On the other hand, a connecting shaft 39 having a shaft portion 38 in which a flat notch surface 37 is formed is attached to the tip of the motor shaft 8 . This shaft portion 38 is inserted into the opening 36 of the spherical body 35, and a pressurizer 40 is fitted between the notch surface 37 and the spherical body 35. This pressurizer 40 has a flat surface 41 that is in close contact with the notch surface 37 of the shaft portion 38 and a cylindrical surface 42 that is in contact with the inner surface of the aperture 36 of the sphere 35.
As shown in FIG. 4, the center axis of the motor shaft 8 is eccentric from the rotation center line XX of the motor shaft 8 by an eccentric amount E. Therefore, when the motor shaft 8 rotates,
The spherical body 35 moves eccentrically with an eccentric amount E with respect to the central axis X-X.

A disk-shaped metal diaphragm 43 is provided between the pump shaft 10 and the motor casing 6, and fluid-tightly partitions the hollow chamber A of the pump casing C from the motor side. In addition, the pump shaft 10 and the motor casing 6
A rotation 1) and a lock 44 are provided between the pump shaft 10 and the pump shaft 10 to restrict rotation around the axis of the pump shaft 10 itself. The diaphragm 43 and the rotation stopper 44 can also be provided between the pump shaft 10 and the main body 1 of the pump casing C.

Next, the operation of this embodiment will be explained.

When the motor shaft 8 rotates, the spherical bearing 340 rotates as described above.
The sphere 35 rotates eccentrically with an amount of eccentricity E. This rotation is absorbed by the spherical bearing 34. and,
Since the rotation of the pump shaft 10 is restricted by the rotation stopper 44, the socket portion 33 provided at one end of the pump shaft 10 does not rotate, and only the eccentric movement of the sphere 35 is transmitted. In other words, the socket portion 33 is driven eccentrically around the central axis XX with an eccentric amount E. This eccentric drive causes the pump shaft 10 to swing around the center point O of the central bearing 11. When the pump shaft 10 swings, the eccentric wheels 16 and 17 provided on both sides of the central bearing 11 move eccentrically and come into contact with the inner circumferential surface of the hollow chamber A at positions symmetrical with respect to the center point O. The eccentric wheels 16° and 17 are attached to the partition member 21.
Although it cannot rotate, it is supported so that it can move in a plane perpendicular to the central axis XX, so this contact point moves as the pump shaft 10 swings.

Look, the outer circumferential surface of the eccentric ring 16 and the inner circumferential surface of the hollow chamber A are in contact at the lowest part as shown in FIG. Assuming that it moves counterclockwise, the aliquot of pump room J) l is 21
The suction chamber partitioned by VC 1) 10 volume increases,
The volume of the discharge chamber po decreases. Therefore, the suction port 26
and the fluid guided through the suction passage 24 is sucked into the pump chamber 1) l from the opening 22, and the fluid in the discharge chamber Po of the pump chamber pl is pressurized and pumped from the opening [-] 23 to the discharge passage 25, It is discharged from the discharge port 27. When the eccentric wheel 16 rises and its point of contact with the hollow chamber A reaches the position closest to the cutout member 21, the volume of the suction chamber P of the pump chamber pl is expanded to the maximum, and the volume of the discharge chamber po is expanded to the maximum. The volume is reduced to the maximum, the suction and discharge strokes are completed, and the state is reached immediately before the start of the next suction and discharge strokes.

From this state, the eccentric wheel 16 further reciprocates in the radial direction against the partition member 21 and swings around it, so that the contact point between the eccentric wheel 16 and the inner circumferential surface of the hollow chamber A moves counterclockwise. When moving to , the previous suction chamber P'L communicates with the opening 23 and becomes the discharge chamber p.

The volume gradually decreases from the most expanded state, and the fluid inside is discharged. Further, the volume of the suction chamber pi communicating with the opening 22 gradually increases 13- to suck fluid from the opening 22. When the contact point between the eccentric wheel 16 and the inner peripheral surface of the hollow chamber A reaches the lowest part farthest from the partition member 21, the suction chamber 7) and the discharge chamber 1)
6 is exactly at the midpoint of the suction and discharge strokes where the volumes are equal to el. This is the situation shown in FIG.

In this way, one cycle of the suction and discharge strokes is completed as the eccentric movement of the eccentric wheel 16 makes one revolution at the point of contact with the inner circumferential surface of the hollow chamber A, and as a result, a volume of fluid equal to the volume of the pump chamber pl is discharged. be done.

Pumping action is carried out in the pump chamber p7 on the eccentric wheel 17 side by a completely similar process. However, since the eccentric wheel 17 always contacts the inner circumferential surface of the hollow chamber A at a position symmetrical to the eccentric wheel 16 with respect to the point O, the pumping action in the pump chambers pt and Pr is exactly 180 degrees.
This results in a phase difference of 14-. Therefore, the pulsation of the fluid 111 skewered from each opening 23 between the pump chamber J) and Pγ is 1800
Since there is a phase difference of , these pulsations are canceled out within the common discharge passage 25. If the volumes of the pump chambers J) l and pr are made equal, fluid can be discharged from the discharge port 27 with almost no pulsation.

When the pump shaft 10 swings, the diaphragm 43 flexibly follows the movement and deforms, without interfering with the movement. Ensure a good seal between.

As described below-4-, according to the present invention, the eccentric wheel IC is made by only rocking the pump shaft without rotating it.
Since the eccentric movement is used to generate a pump action, a sealing member is used to prevent fluid from leaking from the pump chamber to the motor side, etc., between the rotating part and the fixed part. It is necessary to use expensive items such as
It is possible to use a diaphragm, which is inexpensive and has reliable sealing properties. And, since you can also use metal ones for the diamond flannel,
A pump with excellent corrosion resistance and suitable for feeding special fluids can be obtained. In addition, the middle part of the pump shaft is supported so as to be able to swing freely, and eccentric wheels are provided on both sides of the shaft so that the pumping action is performed by each of them. will have
Furthermore, since the discharged fluid is discharged through a common discharge passage, pulsation of the discharged fluid can be reduced. Since these pump actions are performed by eccentric movements in the same direction, sealing between the pump chambers is also relatively easy. Since the sealing of other parts is done by sealing between fixed parts, it can be done extremely easily and completely. Therefore, in some cases, the interior of the hollow chamber of the pump casing can be filled with the delivery fluid.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of an eccentric pump according to the present invention, FIG.
The figure is a cross-sectional view taken along the flll-FIT line in Figure 1.
The figure is a cross-sectional view of the main part taken along line N-IV in FIG. 1. 1... Casing body, 6... Motor casing,
8...Motor shaft, 10...Pump shaft, 11...Center bearing, 16.17...Eccentric ring, 20...Groove, 21...
...Partition member, 22.23...Opening, 24...Suction passage, 25...Discharge passage, 34...Spherical bearing, 3
6... Opening hole, 40... Pressure element, 43... Diaphragm, 44... Rotation stopper, A... Cylindrical hollow chamber, C
...Pump casing, pt, pr...pump chamber,
P B...Suction chamber, PO...Discharge 17- Output chamber, X-X...Central axis patent applicant's envoy Fuji -- 18-

Claims (1)

[Claims] A pump casing (CO) having a cylindrical hollow chamber (A) inside; the middle part is swingably supported in the hollow chamber (, () of this pump casing (C) by a spherical support part (11). , a pump shaft (10) whose one end side does not rotate and is only driven eccentrically by the rotation of the motor shaft (8); supported by the pump shaft (10) on both sides of the support portion (11), A pair of eccentric wheels (16, 1γ) each partially contacting the inner peripheral surface of the hollow chamber (U) due to the swinging of the pump shaft (10) accompanying the drive; A crescent-shaped pump chamber (
p l , p r ) in a fluid-tight manner in the circumferential direction and defining a suction chamber (Pi) and a discharge chamber (P O) respectively; ), and communicates with these suction chambers CPi) and discharge chambers <po), respectively.
24) and the discharge passage (25); the pump shaft (10)
is provided between the one end side of the pump casing (?) and a fixed part such as the pump casing (?), and the hollow chamber (A) is connected to the outside.
An eccentric pump comprising a die (43) for sealing.