EP0859152A2

EP0859152A2 - Rotary pump

Info

Publication number: EP0859152A2
Application number: EP98301015A
Authority: EP
Inventors: Andrew G Olliver; Reginald J Jupp
Original assignee: APV UK Ltd
Current assignee: SPX Flow Technology Crawley Ltd
Priority date: 1997-02-12
Filing date: 1998-02-11
Publication date: 1998-08-19
Also published as: EP0859152A3; GB9702852D0

Abstract

Traditionally the pump inlet and outlet ports are in a horizontal orientation. However, for some applications the ports of the pump are required to be in a vertical orientation.

A rotary pump assembly 1 comprises a rotary pump 2 and pump mounting means 4. The rotary pump 2 comprises a rotor containing assembly 6 and a gear containing assembly 8.

The rotor containing assembly 6 comprises a pair of inter-engaging piston/lobe rotors 10, 12 mounted for contra-rotation within a rotor case portion 7 about substantially parallel axes 13, 14; the rotor case portion is formed with an inlet port 9 and an outlet port 11 and comprises a circular cover plate 111.

Substantially parallel shafts 15, 16 also mounted for rotation about the axes 13, 14 respectively, are connected to the respective rotors 10, 12.

The rotors 10, 12 are secured on to the respective shafts 15, 16 by clamping/retaining nuts 17, 18.

The shafts 15, 16 extend from the rotor containing assembly 6 along the axes 13, 14 through the mounting means 4 and into the gear containing assembly 8.

Description

This invention relates to rotary pumps and is particularly, but not exclusively, concerned with rotary-piston/lobe pumps.

Traditionally the pump inlet and outlet ports are in a horizontal orientation. However, for some applications the ports of the pump are required to be in a vertical orientation. At present the design of the pump has to be substantially altered to enable the orientation to change from the horizontal to the vertical.

According to a first aspect of the invention there is provided a rotary pump assembly comprising a rotary pump and a pump mounting means comprising a mounting surface, the assembly being so arranged that the orientation of the rotary pump relative to the pump mounting means is rotatable about an axis of the pump mounting means; the axis being substantially transverse to the mounting surface, and the rotary pump being secured, in use, to the mounting surface.

The rotary pump is preferably capable of being secured to the pump mounting means in a plurality of orientations at angular intervals of 90° apart.

The rotary pump preferably comprises a gear containing portion, and a rotor containing portion comprising fluid inlet and fluid outlet ports.

The fluid inlet and outlet ports are preferably directed substantially transversely of said axis, whereby when the rotary pump is rotated about the axis by angular intervals of 90° the angular orientation of the inlet port and outlet port will also be rotated about said axis by angular intervals of 90°.

The pump mounting means preferably comprises a frame formed with a through-port substantially coaxial with said axis, and with two such mounting surfaces facing in opposite directions, and the arrangement being such that in use, the rotor containing portion is secured to the first mounting surface, and the gear containing portion is secured to the second mounting surface.

The rotary pump preferably comprises two substantially parallel shafts extending from the gear containing portion through the frame coaxial through port and into the rotor containing portion, the shafts being substantially transverse to the mounting surfaces and each shaft end within the rotor containing portion being attached to a rotor suitably mounted for rotation within the rotor containing portion.

The coaxial through port is preferably formed by a substantially circular coaxial port extending from one mounting surface to the second mounting surface.

The rotor containing portion, is preferably formed with a protruding annular rim extending therefrom and the gear containing portion is preferably formed with a protruding annular rim extending therefrom, the arrangement being such that in use the respective radially outermost surfaces of the annular rims are in contact with the radially innermost surface of the frame.

The rotation of the rotor containing portion and the gear containing portion relative to the mounting frame is preferably substantially prevented by means of at least one dowel-like protrusion extending from the respective mounting faces of the rotor containing portion and the gear containing portion; the protrusions being engaged, in use, in corresponding recesses formed in the respective mounting surfaces of the mounting frame.

Preferably, in use the rotor containing portion and the gear containing portion are secured to the mounting surfaces by means of threaded bolts engaging complementary threaded bolt holes formed in the frame.

According to a second aspect of the invention there is provided a rotary pump gear assembly comprising a load bearing means disposed within a fluid containment means, the arrangement being such that in use the load bearing means provides structural support for the internal component parts of the gear assembly, and the fluid containment means comprises an enclosure to contain lubricating fluid for the internal parts.

An embodiment of the invention will now be described, by way of example only, with reference to the accompanying drawings, wherein:

Figure 1 is a vertical section through a rotary pump assembly and shows the assembly of one of the piston/lobe rotors mounted on a drive shaft, the other piston/lobe rotor and associated shaft being omitted;

Figure 2 is an exploded isometric view of the components of the pump assembly;

Figure 3 is an isometric view of a rotor case portion; and

Figure 4 is an isometric view of a pump cover plate formed with spigot pillars.

With reference to Figures 1 to 4 of the drawings, a rotary pump assembly 1 comprises a rotary pump 2 and pump mounting means 4. The rotary pump 2 comprises a rotor containing assembly 6 and a gear containing assembly 8.

The rotor containing assembly 6 comprises a pair of inter-engaging piston/

lobe rotors

10, 12 mounted for contra-rotation within a rotor case portion 7 about substantially

parallel axes

13, 14; the rotor case portion is formed with an inlet port 9 and an outlet port 11 and comprises a circular cover plate 11¹.

Substantially

parallel shafts

15, 16 also mounted for rotation about the

axes

13, 14 respectively, are connected to the

respective rotors

10, 12.

The

rotors

10, 12 are secured on to the

respective shafts

15, 16 by clamping/retaining

nuts

17, 18.

The

shafts

15, 16 extend from the rotor containing assembly 6 along the

axes

13, 14 through the mounting means 4 and into the gear containing assembly 8.

Shaft 15 is a drive shaft and is driven by an electric motor (not shown) suitably attached at the shaft end 15¹. Prime movers other than electric motors may be used. It will be appreciated that by reversing the direction of the electric motor the direction of fluid flow through the pump containing assembly 6 will be reversed. Accordingly the port 9 will act as the fluid output port and the port 11 will act as the fluid inlet port.

The gear containing assembly 8 comprises a substantially circular chassis plate 20 formed with two

circular ports

22, 24; a chassis structure 26 suitably formed to house two sets of tapered roller bearing

assemblies

28, 29 and carrying a pair of gears 30, 31 mounted on

respective shafts

15, 16 for contra-rotation about the

respective axes

13, 14. The gear containing assembly 8 also comprises a cup-shaped enclosure 33 formed with an open end 34 and a port 35 through which the shaft end 15¹ extends, a lubricant filling port 37 formed through the uppermost region of the enclosure wall and a lubricant drain port 38 formed through the lowermost region of the enclosure wall (see Figure 1). The enclosure 33 is also formed with two substantially circular fluid

level viewing ports

39, 39¹ disposed generally facing each other and being in an orientation 90° from the

ports

37, 38 respectively. It will be appreciated that when the orientation of the rotor containing assembly 6 and gear containing assembly 8 is changed from the vertical to the horizontal orientation the

viewing ports

39,39¹ may be then used as either filling or draining ports and the inlet port 9 and outlet port 11 may be used as fluid level viewing ports. The material used to plug the four

ports

37,38,29 and 39¹ has appropriate transparent properties.

The enclosure 33 is mounted upon an internal support structure 40 which is formed with a port 41 through which the shaft 15 extends. The enclosure 33 is not subjected to substantial stresses during the operation of the pump 1 and the primary function of the enclosure 33 is to contain lubrication fluid within the gear containment assembly 8.

When the enclosure 33 is mounted on the support structure 40 the open end 34 abuts a sealing ring 36 which provides fluid sealing means between the enclosure 33 and the mounting means. Lubrication fluid is placed within the assembly 8 through the port 37 and provides lubrication means for the component parts within the enclosure 33.

The mounting means 4 comprises a substantially vertical portion 42 comprising two substantially parallel

flat mounting surfaces

44, 45 facing in opposite directions. From the lowermost region of the portion 42 there extends a pair of horizontal foot members 47.

The portion 42 is formed with a circular through port 50 extending along axis 52 (see Figure 1). The portion 42 is also formed with a vertical slot 53 which extends through the portion 42 transverse to the axis 52, so forming two substantially parallel

vertical portions

43, 43¹. The

mounting surfaces

44, 45 are each formed with four threaded bolt holes which extend from the

surfaces

44, 45 through the

respective portions

43, 43¹.

Disposed at the upper region of the portion 42 are two

bridging portions

55, 56 extending from the outermost surface of the portion 42 into the slot 53. (See Figure 2.)

The chassis structure 26 of the gear containing assembly 8 is formed with an annular rim 34¹ extending from the chassis structure 26.into the through port 50 of the mounting mean 4. The radially outermost surface of the annular rim 34¹ is in sliding contact with the radially innermost surface of the portion 42.

Referring to Figure 3, the rotor case portion 7 is formed with a generally oval shaped rotor recess 58 adapted to house the

lobe rotors

10, 12. Two substantially circular through

hub bore ports

60, 62 extend from the rotor recess 58 coaxially along

respective axes

13, 14 and are formed so as to receive

seal assemblies

64, 66 disposed on

respective shafts

15, 16.

The inlet port 9 and outlet port 11 extend into the rotor bore 58 from opposing directions. At the innermost part of the inlet port 9 and outlet port 11 there are formed

curved scallops

68, 69.

The rotor case portion 7 is attached to the mounting surface 44 of the mounting means 4 by means of rotor case threaded bolts 70.

The rotor case portion 7 is formed with an annular rim 71 extending from the case portion 7 into the through port 50 of the vertical portion 43. The radially outermost surface of the annular rim 71 is in sliding contact with the radially innermost surface of the vertical portion 43.

The rotor case portion 7 comprises a flat surface 80 substantially perpendicular to the

axes

13, 14. Extending from the mounting surface 80 and through the rotor case portion 7 there are eight threaded bolt holes 82.

Referring to Figure 4, the cover plate 11¹ is formed with bolt holes 84 extending therethrough and arranged so that they align with the respective holes 82 in the rotor case portion 7. Extending from a flat mounting surface 90 into the cover plate 11¹ there are four recesses 92 formed to receive the bolt heads of the rotor case bolts 70. The cover plate 11¹ is also formed with a generally oval shaped channel recess 95 extending from the mounting surface 90 into the cover plate 11. The recess 95 is disposed radially within the recesses 92 and the holes 84. The cover plate 11¹ comprises two stationary substantially

circular spigots

94, 96 each formed with a recess 98 provided to receive the

retaining nuts

17, 18. The outermost wall of each of the

spigots

94, 96 is formed with curved scallop 100 formed to allow the rotation of the

rotors

12, 10.

When the cover plate is bolted to the rotor case 7 an oval seal ring 102 is located within the oval recess 94 and provides sealing means between the

mounting surfaces

80 and 90, so containing fluid being pumped from the inlet port 9 through the recess 58 and out through the outlet port 11.

When the rotary pump assembly 1 is in a substantially disassembled state the orientation of the rotor containing assembly 6 and the gear containing assembly 8 can be rotated by angular intervals of 90° apart, relative to the pump mounting means about the central axis 52 and subsequently reassembled.

It will be appreciated that the orientation of the gear containing assembly 8 and the rotor containing assembly 6 about the axis 52 depends upon the orientation of the fixing holes 51 about the central axis 52. The rotation of the rotor containing portion and the gear containing portion relative to the mounting frame is substantially prevented by means of at least one dowel-like protrusion (not shown) extending from the respective mounting faces of the rotor containing portion and the gear containing portion; the protrusions being engaged, in use, in corresponding recesses (not shown) formed in the respective mounting surfaces of the mounting frame. The four holes 51 can be disposed in any required rotation about the axis 52 from the vertical plane such that the gear containing assembly 6 and rotor containing assembly are disposed in the required orientation about the axis 52.

Claims

A rotary pump assembly (1) comprising a rotary pump (2) and a pump mounting means (4) comprising a mounting surface (44), the assembly being so arranged that the orientation of the rotary pump (2) relative to the pump mounting means (4) is rotatable about an axis (52) of the pump mounting means (4); the axis (52) being substantially transverse to the mounting surface (44), and the rotary pump (2) being secured, in use, to the mounting surface (44).
A rotary pump assembly (1) as claimed in claim 1 wherein the rotary pump (2) is capable of being secured to the pump mounting means (4) in a plurality of orientations at angular intervals of 90° apart.
A rotary pump assembly (1) as claimed in claim 1 or claim 2 wherein the rotary pump (2) comprises a gear containing portion (8), and a rotor containing portion (6) comprising fluid inlet (9) and fluid outlet (11) ports.
A rotary pump assembly (1) as claimed in claim 3 wherein the fluid inlet (9) and outlet (11) ports are directed substantially transversely of said axis (52), whereby when the rotary pump is rotated about the axis (52) by angular intervals of 90° the angular orientation of the inlet port (9) and outlet port (11) will also be rotated about said axis by angular intervals of 90°.
A rotary pump assembly (1) as claimed in claim 3 or claim 4 wherein the pump mounting means (4) comprises a frame formed with a through-port (50) substantially coaxial with said axis (52), and with two such mounting surfaces (44, 45) facing in opposite directions, and the arrangement being such that in use, the rotor containing portion (6) is secured to the first mounting surface (44), and the gear containing portion (8) is secured to the second mounting surface (45).
A rotary pump assembly (1) as claimed in any one of claims 3 to 5 wherein the rotary pump (2) comprises two substantially parallel shafts (15, 16) extending from the gear containing (8) portion through the frame coaxial through-port (50) and into the rotor containing portion (6), the shafts (15, 16) being substantially transverse to the mounting surfaces (44, 45) and each shaft end within the rotor containing portion (6) being attached to a rotor (10, 12) suitably mounted for rotation within the rotor containing portion (6).
A rotary pump assembly (1) as claimed in claim 5 or claim 6 wherein the coaxial through-port (52) is formed by a substantially circular coaxial port extending from one mounting surface (44) to the second mounting surface (45).
A rotary pump assembly (1) as claimed in any one of claims 3 to 7 wherein the rotor containing portion (6), is formed with a protruding annular rim extending therefrom and the gear containing portion (8) is formed with a protruding annular rim (34¹) extending therefrom, the arrangement being such that in use the respective radially outermost surfaces of the annular rims are in contact with the radially innermost surface of the frame (4).
A rotary pump (1) assembly as claimed in any one of claims 5 to 8 wherein the rotation of the rotor containing portion (6) and the gear containing portion (8) relative to the mounting frame (4) is substantially prevented by means of at least one dowel-like protrusion extending from the respective mounting faces of the rotor containing portion (6) and the gear containing portion (8); the protrusions being engaged, in use, in corresponding recesses formed in the respective mounting surfaces of the mounting frame (4).
A rotary pump assembly (1) as claimed in any one of claims 7 to 9 wherein in use the rotor containing portion (6) and the gear containing portion (8) are secured to the mounting surfaces by means of threaded bolts holes engaging complementary threaded bolt holes (51) formed in the frame (4).
A rotary pump gear assembly (1) comprising a load bearing means (40) disposed within a fluid containment means (33), the arrangement being such that in use the load bearing means (40) provides structural support for the internal component parts of the gear assembly, and the fluid containment means (33) comprises an enclosure (33) to contain lubricating fluid for the internal parts.