JPS5888483A - Roller pump - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a roller pump, which includes a rotor and a stator, the stator having a generally cylindrical cavity, a rotor disposed within the cavity, and an axis of rotation of the rotor offset from an axis of the cavity. , the cavity has end walls.

the rotor having a plurality of outwardly facing slots, and a plurality of rollers disposed within each slot, the axes of the rollers being substantially parallel to the previously mentioned axes; , a pair of boats communicate with said cavity, one of said /-) being an inlet dart in use and connected to a source of liquid;
The present invention relates to a roller pump of the type in which the other side of the boat serves as an outflow port for the liquid displaced by the pump as the rotor rotates.

A common implementation f is that the slots are arranged radially, with the sides of the plow slots parallel to and remote from a radial plane containing the longitudinal axis of the roller and the axis of rotation of the rotor. This outfit @I! makes contact with the front trailing edge of the slot and the circle @ second face of the cavity, since the liquid pressure acting on the roller as it passes through the inlet boat tends to press the roller. Pumping action is accomplished only when the rollers come into contact with the inner 914 surface of the cavity, and this contact is first achieved by the action of centrifugal force—unless the speed at which the pump is driven is insufficient to force the rollers outward. If there is, no pump action can be obtained.

The object of the invention is to provide a pump of the type defined above which is simple and convenient to use.

According to the invention, in the pump defined above.

The trailing edge surface of each slot is sloped away from a radial plane containing the longitudinal axis of the roller and the axis of rotation of the rotor, so that as the rotor rotates - exhibits a natural tendency to roll outward.

Another aspect of the invention is that the at least one roller includes a resilient device operative to bias the end of the roller into rubbing contact with the end wall of the cavity.

In FIG. 1, this known type of pump includes a stator having a generally circular cavity 10 therein, the shell cavity having an end wall 25 (not shown in FIG. 1), and having a generally circular cavity 10 therein. The axis line is shown at 111. A rotor 12 is installed in this cavity, and the diameter of the rotor is /J% smaller than the diameter of the cavity 10.
and having an axis of rotation indicated at 13 offset from the axis 11, inlet &-) 14 and outlet ports 15 are located in the cavity, these boats having a considerable length in the internal direction and Formed in the cylindrical wall of the cavity.

Radial slots 16 arranged at four angles are formed on a diagonal and a roller 17 is slidably disposed within each slot. The plane 111 of the slot fits parallel to a plane containing the rotational axis of the rotor and the longitudinal axis of the roller 17, but extends at a distance from this plane. The direction of rotation of the rotor within the cavity is indicated by arrow 18A. Regarding the operation of the pump, the row 217 of the rotor is pushed outward by the action of centrifugal force, and the rotor moves into the cavity II! The row 2 shall be driven at a sufficient speed to ensure line contact with one surface. This line contact will provide a seal and the ends of the rollers will be in close proximity to the side walls of the cavity to further provide a seal. In FIG. 2, roller 17
For purposes of illustration, the row 217 is shown to be considerably smaller than the slot in which it is disposed, and from this figure a line contact is formed between the six faces of the cylinder, and this contact is designated by the letter B and further It can be seen that a line contact is formed between the trailing edge surface of the slot and that this contact is A-contact. The roller is biased into this configuration by the pressure drop between the outlet and the inlet, and the ultimate force acting on the roller is in the direction indicated by X.

As the rotor rotates, the rollers push the liquid towards the outflow port and the liquid passes through this inflow port as the volume of the progressively shaped portion of the cavity increases as the roller moves towards the uppermost part. drawn into the shape part. The above explanation assumes that the roller 17 is in contact with the surface of the hollow circle Iv1, which means that a centrifugal force is acting from the beginning. Ba.

Such contact never occurs, or even if it does, the weight of the rollers and the fluid forces acting on them are insufficient to maintain contact with the inner cylindrical surface as the rotor rotates. It will be.

Next, at the third turn, the rotor 18 is moved so that the slot 19 no longer has a radial angle and the trailing edge of the slot 111D2° is the axis of rotation of the roller 1111! The plane containing ll and the longitudinal axis is no longer parallel. This #L oblique angle is indicated by arrow C-c. The effect of this deformation is that as the rotor rotates, there is a self-combusting tendency for the rollers to roll outward and into contact with the surface 10. In the device shown in FIG. 3, this hole no longer has a radial orientation, so that the leading edge of the slot cannot actually be raised. Thus, because of the pump's natural tendency to push the rollers outward, the pump shown in FIG. 1 can also operate satisfactorily at low speeds.

This rolling action is improved by modifying the rollers as shown in FIG. In this figure, the end wall of the cavity is shown and one roller is indicated at 22. Each roller has an inner bore and is slidably biased outwardly into frictional engagement with the end wall of the cavity by an elastomer aIK in the form of a helical compression spring 24 disposed within the bore. It has a compression pad 23. The statement ◆ that this Nomurad 23 is pressed against the 10,000 end wall means that the opposite end of the roller is also pressed against the overlying wall. This modification increases the tendency of the roller to move outward, and the frictional engagement with the end wall of the cavity causes the roller to fall to the inverted end of the slot in which it is housed under the action of one gravitational force. Minimize risk.

While the pump described with reference to FIGS. 1 and 2 can only be operated in one direction, the pump shown in FIG. 3 only exhibits its advantages when the rotor rotates in one direction. To achieve the above advantages, the slots are shaped as shown in FIG.
That is, the sides 25 of the slot are widened outwardly from each other. FIG. 5 also shows that in this case the generally cylindrical outward contour shape of the cavity has been further modified. It is located between the inlet port and the outlet /-1 and is arranged so as to constitute an arc surrounding the center of rotation of the rotor, which is partially open on the surface of the cavity where the rotor approaches the wall of this cavity. By careful design and construction, the rollers
Rino place *'l? Iwao contact.

The first one can be placed in contact with the inner 1119 surface of the cavity, and the second and third ones can be in contact with each of the slots 11EI25. But in actual case, fi
! Contact is obtained only in two positions, but the gap in the third position is small. The advantage of this modified configuration is that as the roller moves away from the outlet port, the pressure acting on the roller forces it towards the opposite side wall of the slot and displaces fluid during this movement.

Also, a leakage path exists between the roller and the sidewall of the slot. This results in a loss of volumetric efficiency of the pump. In the apparatus shown in FIG. 5, as soon as the roller leaves the outlet/-) 15, the two-position engagement condition described above occurs, and the movement of the roller away from the R outlet port is minimized. Furthermore, the leakage portion of the roller is small.

Knot 23 is not necessarily necessary 1, but Kabane Sae is hollow Ill! It can come into contact with the iIc end wall 21. It will be appreciated that in this modified embodiment, it is necessary for the end wall to be smooth and that no discontinuities are formed, and that the inlet and outlet ports are also formed in the end wall.

It is known that the efficiency of a pump using eight rollers, for example of the type shown in FIG. 4, can be increased if some of the rollers are replaced by simple rollers.

[Brief explanation of drawings]

FIG. 1 is a top view of a conventional pump, FIG. 2 is a partial structural view 111 of the example shown in FIG. 1, and FIG. 3 is a view similar to FIG. 1 showing a pump modified according to the present invention. Figure 4 shows the roller with the pump modified.
- The sectional view through FIG. 5 shows another variant. Symbols in the figure: 10...Cavity, 11...Cavity axis, 1
2... Rotor, 13... Rotor rotation axis, 14...
...Inflow port, 15...Outflow port), 16...Slot hole, 17...P-RA, 18...Rotor, 19...
Slot, 20... trailing edge surface. 21... End wall, 22... Roller, 23... Pressure cutter P. 24...Spring, 25...Side surface, 326...Cavity narrow surface part. shows. Representative Patent Attorney (8107) Takayoshi Sasaki (and 3 others)
given name)

Claims (1)

Claims: 1) includes a rotor and a stator, the stator having a generally cylindrical cavity, the rotor disposed within the cavity, the axis of rotation of the rotor being offset from the axis of the cavity, and the cavity extending from an end wall. a plurality of outwardly extending slots are formed in the rotor, and a plurality of rollers are respectively disposed within the slots, the @ lines of the rollers being parallel to the axes of the rotor and the cavity; The stator further has a pair of ports in communication with the cavity, one of which is connected to a source of liquid as an inlet port in use and the other is an outflow port for the liquid to be removed by the pump when the rotor rotates. In a roller pump that functions as a stator, the trailing edge of each slot is inclined away from the radial plane containing the longitudinal axis of the rotor and the axis of rotation of the rotor, so that when the rotor rotates, the rollers are oriented within the stator. A roller pump characterized in that it has a natural tendency to roll outward in a slot towards. 2) at least some rollers at the ends of the rollers; 2. A roller pump as claimed in claim 1, including a resilient device operative to bias into frictional contact with the end of the cavity. 3) A roller pump according to claim 2, wherein the roller containing the elastic device has an inner bore containing a slidable pressure pad, and the elastic device is in the form of a compression spring arranged in the inner bore. 4) The roller pump according to claim 1, wherein both sides of each slot are bent toward the outside of the rotor. 5) A roller pump according to claim 4, wherein the portion of the cavity located between the inflow and outflow ports and generally on the side of the axis of rotation of the rotor with respect to the axis of the cavity has an axis that coincides with the axis of rotation of the rotor.