Screw spindle pump

Abstract

A screw spindle pump having a housing hi which a drive spindle and at least one running spindle having profile assemblies which engage inside each other are received, the free end of the drive spindle and the end portion of the running spindle being supported on a plate which is arranged in the housing, the plate having two faces which are inclined in opposing directions relative to each other and which form a V-shape and on which one of the spindles is supported, respectively.

Claims

1. A screw spindle pump, comprising: a housing; a drive spindle; a running spindle, the drive spindle and the running spindle being arranged in the housing and having profile assemblies which engage inside each other; a plate arranged in the housing, the plate having a first side and a second side, the first side facing the drive spindle and the running spindle, and the second side facing away from the drive spindle and the running spindle, a free end of the drive spindle and an end portion of the running spindle being supported on the first side of the plate, wherein the first side of the plate has two faces that are inclined in opposing directions relative to each other and form a V-shape, each of the two faces supports a respective one of the drive spindle and the running spindle.

2. The screw spindle pump according to claim 1, wherein the inclination of the faces is such that the drive spindle and the running spindle are arranged parallel with each other during operation of the screw spindle pump.

3. The screw spindle pump according to claim 1, wherein an inclination angle between each of the faces and the plate is from 2° to 30°.

4. The screw spindle pump according to claim 3, wherein the inclination angle is from 2° to 12°.

5. The screw spindle pump according to claim 3, wherein both of the two faces have a common angle of inclination.

6. The screw spindle pump according to claim 3, wherein at least one of the free end of the drive spindle or the end portion of the running spindle has a tapered tip with an angle of taper smaller than the inclination angle between the inclined faces and the plate.

7. The screw spindle pump according to claim 1, wherein a first of the inclined faces has a lateral inclination with respect to a longitudinal side of the plate and a second of the inclined faces has a lateral inclination with respect to an opposing longitudinal side of the plate.

8. The screw spindle pump according to claim 7, wherein the lateral inclination of the first and the second faces is from 2° to 30°.

9. The screw spindle pump according to claim 8, wherein the lateral inclination is from 2° to 12°.

10. The screw spindle pump according to claim 1, wherein the two inclined faces are spaced apart from each other by a groove.

11. The screw spindle pump according to claim 1, wherein the plate is constructed as a feather key.

12. The screw spindle pump according to claim 1, further comprising a second running spindle, wherein the running spindle and the second running spindle are arranged at opposing sides of the drive spindle.

Description

BRIEF DESCRIPTION OF THE DRAWING

(1) In the drawing:

(2) FIG. 1 is a perspective view of a plate of a conventional screw spindle pump;

(3) FIG. 2 is a side view of the plate of FIG. 1;

(4) FIG. 3 is a front view of the plate shown in FIG. 1;

(5) FIG. 4 is a sectioned side view of a screw spindle pump according to the invention;

(6) FIG. 5 shows a plate of the screw spindle pump shown in FIG. 4;

(7) FIG. 6 is a side view of the plate shown in FIG. 5;

(8) FIG. 7 is a front view of the plate shown in FIG. 5;

(9) FIG. 8 shows another embodiment of a plate for a screw spindle pump according to the invention;

(10) FIG. 9 shows a plate for a screw spindle pump according to the invention with a drive spindle and two running spindles; and

(11) FIG.10 shows an embodiment in which a drive spindle and a running spindle have tapered ends.

DETAILED DESCRIPTION OF THE INVENTION

(12) FIG. 4 shows the significant components of a screw spindle pump 5, comprising a housing 6, in which a drive spindle 7 and a running spindle 8 are received. Both spindles have profile assemblies which mesh with each other. An electric motor 9 drives the drive spindle 7; by means of the opposing rotation of the two spindles 7, 8, a fluid, for example, a fuel for a combustion engine, is drawn through an intake nozzle 10. The fluid flows through the electric motor 9 and leaves the housing 6 via an outlet 11.

(13) The free end of the drive spindle 7 and the end portion of the running spindle 8 are supported on a plate 12 which is arranged in the housing 6 transversely relative to the spindles. At both sides of the plate 12, there is provided a free space which is delimited by the housing 6 so that the fluid can flow in through these free spaces.

(14) FIG. 5 is a perspective view of the plate 12. The plate 12 has in a manner corresponding to the plate shown in FIG. 1 the basic shape of a feather key; in contrast to the plate of FIG. 1, the plate 12 has at the upper side thereof two faces 13, 14 which are inclined in opposing directions with respect to each other and on which one of the spindles is supported in each case. The arrows 3, 4 are a symbolic representation of the longitudinal axis of the running spindle and the drive spindle. The inclination of the two faces 13, 14 is selected in such a manner that they intersect along a (notional) line, as can best be seen in the side view of FIG. 6. The two faces 13, 14 are inclined with respect to each other so that they form at least a slight V-shape. For technical production reasons, a transversely extending groove 15 is provided between the two faces 13, 14. The inclination of the two faces 13, 14 which is visible in FIG. 6 counteracts the described crossing of the spindles so that they are retained at the ideal position so that they are arranged in a parallel manner.

(15) FIG. 7 is a view of FIG. 6 rotated through 90° and shows symbolically via the two arrows that the axes of the drive spindle 7 and the running spindle 8 are also precisely parallel in this plane. At the same time, the drive spindle 7 and running spindle 8 are arranged precisely perpendicularly with respect to the transverse direction which corresponds, for example, to the lower side 16 of the plate 12.

(16) In FIG. 5, it can be seen that the two inclined faces 13, 14 are additionally inclined in opposing directions with respect to longitudinal sides of the plate 12. The face 13 is in the view of FIG. 5 inclined in a forward direction, the face 14 in contrast in a backward direction, The combination of the faces 13, 14 which are inclined twice, that is to say, about two axes of rotation, ensures that no crossing of the spindles 7, 8 occurs and that they are retained in a precisely parallel manner at the desired ideal position. The end portions of the two spindles 7, 8 each have an angle of taper which is smaller than the angle of inclination.

(17) FIG. 8 shows another embodiment of a plate for a screw spindle pump. The plate 21 has two faces 22, 23 which are inclined in opposing directions with respect to each other and which form a V-shape and on which one of the spindles 7, 8 is supported in each case. In contrast to the embodiment shown in FIGS. 5 to 7, the plate 21 has no groove, The inclined faces 22, 23 are constructed in a symmetrical manner and extend from a centre plane of the plate 21 as far as a raised position which is located further outward, whereby the V-shape is formed. The faces 22, 23 are inclined only about one axis. For technical production reasons, the plate 21 illustrated in FIG. 8 is preferred over the other embodiments.

(18) FIG. 9 is another embodiment and shows a plate 17 which is provided for a screw spindle pump having a drive spindle and two leading spindles. The two leading spindles are located at opposing sides of the lead spindle. The plate 17 comprises two faces 18, 19 which are inclined in opposing directions with respect to each other and on which the lead spindles are supported. Between them is a planar face 20 on which the drive spindle is supported in an axial manner. The two running spindles, as a result of the inclined faces 18, 19, orientate the drive spindle and are also inclined in opposing directions relative to each other with respect to the notional connection line in a similar manner to the faces 13, 14 of the plate 12.

(19) FIG. 10 shows an embodiment in which the ends 24, 25 of the drive spindle 7 and the running spindle 8 facing the plate 12 are tapered. The depiction in FIG. 10 is not meant to disclose any specific angles of the tapered ends 24, 25.

(20) While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.