DE3309587C2 - Displacement machine for fluids - Google Patents

Abstract

Spiral or annular piston displacement machine with a displacement body formed from a rib in a housing provided with correspondingly shaped walls, the axial movement gaps of which are minimized by sealing elements that have a U-shaped cross section and enter recesses in the displacement body and the housing walls during the displacement movement.

Description

The invention relates to a spiral or rotary piston displacement machine with a displacement body formed from at least one rib in a housing provided with correspondingly shaped walls, wherein the axial movement gap between the displacement body and the housing by sealing elements with a U-shaped cross section is minimized in the area of the axial ends of the rib of the displacement body.

Such Ve: Jrängermaschinen have a unidirectional conveying process .auf, so that their use as a compressor or vacuum pump is advantageous where there is a high compression without or at least Lubrication is to be achieved.

However, this requires precise rolling and sealing between the rib of the displacement body and the housing wall necessary to achieve acceptable efficiency, with wear or Seizing of the displacement body should be excluded.

The seal affects on the one hand the radial contact points forming the delivery chamber and on the other hand the necessary axial movement gaps, the latter with considerable power losses due to its length cause that are far larger than those caused by the contact points. For this reason, for example has been proposed in US-PS 39 94 635, the axial movement gaps by sealing elements to minimize, which are arranged in grooves or on webs of the rib.

However, this requires the rib of the displacement body to widen by the amount of the width of the sealing elements, thereby increasing the size of the moving masses becomes necessary, which restricts the drive speed or changes the camp conditionally.

The object of the invention is therefore to provide a spiral or rotary piston displacement machine for the use of To design sealing elements so that a minimum wall thickness of the rib of the displacement body on the sealing elements is achieved.

This object is achieved according to the invention in that the housing walls have recesses in which enter the side walls of the sealing elements when the displacement body approaches the housing walls during the displacement movement.

The invention provides tolerances for an economical Manufacturing has become achievable and a smaller dimensioning of the components and possibly of the machine as a whole, since the efficiency of the machine is improved.

An embodiment of the invention is shown in the drawings and is described below. It shows

F i g. 1 shows a cross section of a displacement machine according to the invention,

F i g. 2 a longitudinal section,

F i g. 3 a displacement body with a sealing strip.

The invention is illustrated and described on a scroll displacement machine. However, it is because of the Similarity of the spiral principle with the ring piston principle also to a ring piston displacement machine transferable.

The displacement machine includes two housing halves 1, 2, whereby the housing half 1 is provided for supporting a crankshaft 3, which is provided with a pulley 4, the eccentric crank pin 5 of the crankshaft 3 is "n a hub 6 mounted a sinker 7 on a disk 8, as well as a (spiral) rib 9 is arranged axially protruding therefrom on both sides. The housing half 2 has a connection tract 10 for a consumer, arranged centrally in the axial direction. A second connecting section 11 for the supply or discharge occurs tangentially to the outer diameter of the housing and is formed from the housing parts 1, 2

If the crankshaft 3 is set in rotation, then the displacement body 7 moves and performs a Relative movement of locally different sizes, whose envelope curve through recesses and walls of the

j5 housing halves 1, 2, wrapped around them forming a housing spiral is, so that constantly at least two radial, gap-like, linear contact points 14, 15 between the (spiral) rib 9 dfts contraction body 7 and the housing wall 13 exist, between which sickle-shaped delivery chambers are formed in which a fluid can be promoted unidirectionally as a result of the movement mentioned. Since every crank pin revolution Temporarily set two contact points on the inner and on the outer surface of the housing wall 13, arise inner and outer conveying chambers, so that conveying is carried out continuously during one revolution.

In Fig. 2 sealing elements 16, 17, 20, 21 are shown, which the free-standing part of the housing wall 13 and the (spiral) rib 9 of the displacement body 7 radially and axially protruding therefrom, afflicted with a minimal gap, encompass displaceably. There are also recesses 18, 19,22,23 shown, in which the walls 24,25 of the sealing elements 16, 17, 20, 21 when the displacement body approaches during the displacement movement enter.

F i g. 3 shows the displacement body 7 with the (spiral) rib 9, which is partially for receiving the sealing elementc 16, 17 is axially lowered, which is analogously the same for receiving the sealing elements 20, 21

bo be carried out in the case of the free-standing housing wall 13 got to. The recess 22 in the area of the disk 8 can be seen on the (spiral) rib 9. The sealing elements should wrap around the rib 9 of the displacement body 7 over at least 360 °, as this always the Pressure chambers are sealed against the suction chambers by sealing elements.

Beginning and end of the sealing elements 16, 17, 20, 21 can be round, square or beveled.

1 3

P The choice of material for the contact surfaces in the housing and on the displacement body and for the sealing M elements was made for low friction, with the || Sealing elements already successfully a polyimide (PI) was put in agreement that a high temperature resistance || having

rl If the movement gap for the crank arm 12

^! ß in the opening of the free-standing housing wall 13 with

p. is sealed with a sealing element, it can be advantageous

J "be liable, the sealing element is integral with the sealing

ψ? _: ment 20 or 21, especially since this at the same time

ipi tig a protection against migration of the sealing element

P is reached on the spiral.

= g During the promotion, the contact points Iy 14,15 of the displacement body 7 move to the housing wall 13 fiö along the spiral. Thus, any pi point on the displacement body approaches during a = 5j revolution of the housing wall, so that the side walls 24, H 25 of the sealing elements 16, 17 in the area of the contact points 14, 15 encroach into the recesses IS, 19 th.

ig It is necessary that the recesses 18, 19 to

': ■■: ■ contactless mounting of the sealing elements 16, 17

ψ: are suitable, d. h, it must be between the housing wall

£ '■ and the sealing element that has entered a small gap

$ remain i.

f-l There must also be a small gap between the side

Cj walls 24, 25 of the sealing element and the spiral rib

ίί of the displacement body 7 exist to an axial

> ä Displaceability of the sealing elements and thus the

Γ. sealing contact of the sealing elements on the axial cylinder

iι; reach linder walls.

For this purpose 3 sheets of drawings

35

40

45

Claims (1)

Claim: Spiral or rotary piston displacement machine with a displacement body formed from at least one rib in a with correspondingly shaped Walls provided housing, the axial movement gap between the displacement body and housing through sealing elements with a U-shaped cross section in the area of the axial ends the rib of the displacement body is minimized, characterized in that the housing walls Have recesses (18, 19) into which the side walls (24, 25) of the sealing elements (16, 17). when the displacement body (7) approaches the housing walls during the displacement movement, enter.