Housing for a rotary vane pump

Abstract

A housing for a rotary vane pump includes a suction flange and a discharge flange having a multi-angular cross-section with at least two sides extending parallel to each other, cooling ribs provided on an outer surface of the housing, with the number of cooling ribs in the region with a high internal pressure being greater than a number of cooling ribs in the region with a low internal pressure, inlet and outlet, with the inlet cross-section being greater than the outlet cross-section, and connection elements provided on the housing and each having two installation surfaces connected by a connection surface.

Claims

1. A housing for a rotary vane pump, comprising a suction flange (6) and a discharge flange (7) located opposite each other; and two additional flanges (3, 4) arranged on opposite axial sides of the housing, respectively, and each having at least two connection elements (30, 31) for securing the housing, the connection elements each having two installation surfaces arranged at a 90°-angle to each other, and a connection surface for connecting the two installation surfaces and arranged at a 45°-angle to the installation surfaces.

2. A housing according to claim 1, wherein intersection lines of the installation surfaces and the connection surfaces are formed as bevels.

3. A housing according to claim 1, wherein at least one of the installation surfaces and the connection surface has a bore with an inner thread.

4. A housing according to claim 1, wherein the additional flanges of the housing each has a cover for vacuum tightly sealing the housing.

5. A housing according to claim 1, wherein at least one of the suction flange and the discharge flange has a hole pattern for ISO-connection and DIN-connection, with the bores being arranged radially symmetrically in the at least one of the suction flange and the discharge flange.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The drawings show:

(2) FIG. 1 a perspective view of a housing according to the present invention with a high vacuum connection flange;

(3) FIG. 2 a perspective view of a housing according to the present invention with a forevacuum connection flange;

(4) FIG. 3 a side view of the housing;

(5) FIG. 4a a front elevational view of the housing with separate feet in an axial direction;

(6) FIG. 4b a front elevational view of the housing mounted on a stand in the axial direction;

(7) FIG. 5 a cross-sectional view of the housing;

(8) FIG. 6 a bottom view of the housing provided with a discharge flange;

(9) FIG. 7 a top view of the housing provided with a suction flange;

(10) FIG. 8 a longitudinal cross-sectional view of the housing;

(11) FIG. 9 a perspective view of a housing according to the present invention with a cover.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(12) FIG. 1 shows a housing 1 of a rotary vane pump. In the compression chamber 2, there are arranged two, not shown, rotors synchronously rotatable, in a non-contact manner, in opposite directions. The rotors have a shape of “8” and are separated from each other and from respective stators by a gap.

(13) The housing 1 is shown in FIG. 1. The flanges 3 and 4 are equipped during an operation with covers 52, 53, as shown in FIG. 9, and which tightly abut the flanges 3 and 4. In addition, as shown in FIG. 1, the flange 3 is provided with a groove 5 for receiving a seal. As shown in FIG. 9, shafts 54, 55 for rotors extend through the covers 52, 53.

(14) According to FIG. 1, the housing 1 has a suction flange 6 and a discharge flange 7. The suction flange 6 has a square basic surface in corner regions of which, recesses 8, 9, 10, 11 in form of notches extending into the basic surface of the flange 6 are provided. Sides 12, 13 of the flange 6 extend parallel to each other, can be aligned with the flanges 3, 4 and end, according to FIG. 1, at the end surface of the flanges 3 and 4. The sides 14, 15 of the flange 6 likewise extend parallel to each other. In the sides 14, 15 of the flange 6, measuring boreholes 16 are provided.

(15) The recesses 8, 9, 10, 11 in the basic surface of the flange 6 permit to achieve weight reduction. In addition, the flange 6 can be more easily produced.

(16) Moreover, in the regions 17, 18 of the housing 1 and in the corresponding regions on the opposite side, a better cooling is achieved as these regions are not covered by the flange material.

(17) The construction of the flange 6 with parallel opposite sides 12, 13 also makes possible to form the housing 6 noticeably shorter in the axial direction than was the case with a round flange as the flange should not project beyond the housing.

(18) The flange 6 has two hole patterns. The first hole pattern for DIN-standard consists of bores 19. these bores are arranged in the flange 6 outwardly. The second hole pattern for ISO-standard consists of bores 20. Inwardly of bores 20 provided for the ISO-standard, a groove 21 for O-ring seal is provided to achieve a tight connection upon connection of the flange 6 with a connection flange (not shown).

(19) The housing 1 has cooling ribs 22, 23, 24, 25, 26, 27 and 57, 58, 59, 60. The upper portion 28 of the one-piece housing, i.e., the region in which a smaller compression of the pumping medium takes place, has only one cooling rib 22, whereas a lower portion 29 of the housing 1 has five cooling ribs 23 through 27 and 57 through 60. In the lower portion 29 of the housing 1, the pumping medium is noticeably greater compressed, so that here a much greater temperature is reached than in the upper portion 28. In order to achieve a uniform cooling of the housing, without any temperature gradients, a greater number of cooling ribs 23 through 27, 57 through 60 is provided in the lower portion 29 than in the upper portion 28.

(20) Because of different number of the cooling ribs, tensions and deformations in the housing 1 and, thereby, e.g., displacement of the support points, are prevented or preventable.

(21) The flanges 3, 4 are provided with connection elements 30, 31. The connection elements 30, 31 have installation surfaces 32, 33 arranged at 90° angle towards each other. The installation surfaces 31, 32 are connected with each other by a connection surface 34. The connection surface 34 is arranged relative to the collection areas at an angle of 45°.

(22) A circular inlet opening 42 is provided in the suction flange 6. Likewise, the discharge flange 7 has a circular opening 35.

(23) FIG. 2 also shows the housing 1. The same components are designated with the same reference numerals. According to FIG. 2, the discharge flange 7 is clearly visible as it is located on top.

(24) The discharge flange 7 has, as the suction flange 6, a basic square shape, and in the corner regions, recesses 36, 37, 38, 39 are formed, as in the flange 6, as inwardly projecting radii.

(25) FIG. 3 shows a side view of the collection areas at an angle of 45°.

(26) A circular inlet opening 34 is provided in the suction flange 6. Likewise, the discharge flange 7 has a circular opening 35.

(27) FIG. 2 also shows the housing 1. The same components are designated with the same reference numerals. According to FIG. 2, the discharge flange 7 is clearly visible as it is located on top.

(28) The discharge flange 7 has, as the suction flange 6, a basic square shape, and in the corner regions, recesses 36, 37, 38, 39, as in the flange 6, as inwardly projecting radii FIG. 3 show a side view of the housing 1, with cooling ribs 22 in the first portion 28 of the housing 1 and cooling ribs 23 through 27 and 57 through 60 in the second portion 29 of the housing 1.

(29) The cooling ribs 22 through 27 and 57 through 60 are arranged radially along the envelope lines of the housing 1. With the recesses 10, 11 in the flange 6 and recesses 38, 39 in the flange 7, the regions 17, 18, 40, 41 of the housing are better cooled than in the absence of the recesses 10, 11.

(30) FIG. 4a shows the housing 1 with the flange 3. On the housing, connection elements 30 are provided which have installation surfaces 32, 33 and the connection surface 34. The installation surfaces are arranged to each other at an angle of 90°, installation surfaces 32, 33 provide for mounting of the housing 1 on a stand or a corresponding fast mounting. In the connection surfaces 34, a bore 43′ is provided, respectively, in which a fastening element 45 can be located. The construction prevents action of shearing forces on the fastening elements, e.g., screws.

(31) According to FIG. 4a, a foot mounting 43 is provided for each connection element 30. The foot mounting 43 has a through-bore 44 through which a screw 45 engageable in connection element bore having an inner thread, extends. Both fast mountings can be connected to form a common foot mounting or be connected to a stand, as shown in FIG. 4b.

(32) Because transmission of the gravity force takes place over surfaces extending transverse to the gravity force, action of the shearing force on the fastening elements, screws 45, is prevented. The housing 1 can also be mounted vertically, using the same foot mounting 43.

(33) The connection elements 30 have, as shown in FIG. 1, face surfaces 46 for insuring a flat abutment of both installation surfaces 32, 33.

(34) FIG. 5 shows a cross-sectional view of the housing 1 of a vacuum pump.

(35) The housing 1 has a suction flange 6 and a discharge flange 7. The diameter d.sub.1 of the suction opening 42 is greater than the diameter d.sub.2 of the discharge opening 35 of the flange 7. The opening 42 is preferably circular but changes into a rectangular opening 47 in the region of the inner wall 48. The same occurs with the opening 35 that changes in a rectangular opening 49. In the region of the intersecting planes that is shown in FIG. 5, the transition of the opening 42 in the rectangular opening 47 narrows in the direction of the compression chamber 2 and is formed by side walls 50. The same takes place for the opening 35 that conically narrows in the rectangular opening 47, with the transition being formed by side walls 51. The transition of the openings 35, 42 in the rectangular opening 47, 49 takes place smoothly.

(36) The rectangular opening 47 has, viewing in the direction transverse to the longitudinal axis of the housing 2, a smaller extension l.sub.1 than the diameter d.sub.1 i.e., l.sub.1 is smaller than d.sub.1.

(37) The rectangular opening 48 has likewise, viewing in the direction transverse to the longitudinal axis of the housing 2, a smaller extension l.sub.2 than the diameter d.sub.2 i.e., l.sub.2 is smaller than d.sub.2.

(38) In addition, the diameter d.sub.1 of the opening 42 is greater than the diameter d.sub.2 of the opening 35. Also, the extension l.sub.1 is greater than extension l.sub.2. This means that the forevacuum cross-section is noticeably smaller than the high vacuum cross-section, whereby the energy efficiency is optimized at the same volume characteristic. Advantageously, the forevacuum cross-section is by about 50% smaller than the high vacuum cross-section.

(39) FIG. 6 shows the housing 1 with the discharge flange 7. One can see in FIG. 6, narrowing of the cross-section by formation of the rectangular opening 49.

(40) FIG. 7 shows the housing 1 with the suction flange 6. Here also one can see narrowing of the cross-section of the opening 42 by formation of the rectangular opening 49.

(41) FIG. 8 shows a longitudinal cross-sectional view of the housing 1 with the suction opening 42 and the discharge opening 35 which change into rectangular openings 47, 49. Here also one can see a smooth transition that prevents stalling.

(42) FIG. 9 shows the housing 1 with features shown in FIG. 1. According to FIG. 9, the housing is vacuum-tightly closed, from both sides, with a cover 52, 53, respectively. The shafts 54, 55 of the rotors (not shown) extend through the cover 52 (not shown) and the cover 53.

(43) Though the present invention was shown and described with references to the preferred embodiments, those are merely illustrative of the present invention and is not to be construed as a limitation thereof and various modifications of the present invention will be apparent to those skilled in the art. It is, therefore, not intended that the present invention be limited to the disclosed embodiments or details thereof, and the present invention includes all variations and/or alternative embodiments within the spirit and scope of the present invention as defined by the appended claims.