VOLUME RATIO FOR A R718* COMPRESSOR

Abstract

Compression of water vapour as R718 is disclosed with and without addition of additives as an aqueous solution in rotational displacement machines, i.e. refrigeration, air-conditioning and heat pump technology. To largely avoid over or under-compression, it is proposed for the easiest possible adaptation of the currently effective internal volume ratio as so-called iV value in the displacer that the compressor housing starting from the outlet side with rotor profile length L.sub.R over a length L.sub.iV comprises planar, i.e. flat iV disks (3.sub.j) with the index j for 1≤j≤n; n is the number of disks; n≥1 with a width b.sub.j per iV disk having planar surfaces P.sub.F preferably perpendicular to the neutral axis A.sub.N. The iV disks are displaced in a targeted manner individually by movement control devices (5.sub.j) per iV disk in each case by a distance s.sub.i where 0<s.sub.i≤s.sub.j.

Claims

1. A R718* compressor as a two-shaft rotational displacement machine for conveying and compressing gaseous conveyed media, comprising: a spindle rotor pair in a compressor housing at a pressure p.sub.1 at a compressor inlet and during operation with a higher pressure p.sub.2 at a compressor outlet; wherein for the respective adaptation of an internal volume ratio (as “iV value”) of the R718* compressor, the compressor housing thereof starting from the outlet side with a rotor profile length L.sub.R over a length L.sub.iV comprises planar, i.e. flat iV disks (3.sub.j) with the index j for 1≤j≤n where n is the number of these iV disks (3.sub.j) where n≥1 with a width b.sub.j per iV disk (3.sub.j) having planar surfaces P.sub.F, wherein the iV disks (3.sub.j) for the respective operating conditions are specifically individually displaced via movement control devices (5.sub.j) per iV disk (3.sub.j) in each case by a distance s.sub.i where 0<s.sub.i≤s.sub.j with s.sub.j as the maximum displacement distance per iV disk (3.sub.j) and thus gas emissions G.sub.o1 and G.sub.o2 as well as G.sub.oS into a condensation chamber are made possible in such a manner as to largely avoid over or under-compression which is harmful to the efficiency in such an R718* compressor.

2. The R718* compressor according to claim 1, wherein a precise positioning of each iV disk (3.sub.j) is accomplished via position pins with respect to the compressor housing and with respect to one another so that in the closed state when all the iV disks (3.sub.j) abut in a clearly defined manner against one another via the position pins, clearance values between the spindle rotor pair and the compressor housing are always maintained, wherein a production machining of an internal contour of the compressor housing is accomplished in this state of the completely abutting iV disks.

3. The R718* compressor according to claim 1, wherein the movement control devices (5.sub.j) per iV disk (3.sub.j) are operated with R718* water hydraulics and for each operating point any intermediate position s.sub.i where 0<s.sub.i≤s.sub.j with s.sub.j as the maximum displacement distance per iV disk (3.sub.j) is made possible.

4. The R718* compressor according to claim 1, wherein the planar surfaces (P.sub.F) per iV disk (3.sub.j) are designed for easy sealing with respect to one another and with respect to the compressor housing with correspondingly smooth, shiny and preferably ground surfaces.

5. The R718* compressor according to claim 1, wherein guide support surfaces (F.sub.F) are designed in such a manner that during displacement of the respective iV disks (3.sub.j) with correspondingly suitable application of force via the movement control devices (5.sub.j) for displacement of the respective iV disks (3.sub.j) a circumferentially uniform movement of the respective iV disks (3.sub.j) over corresponding guide lengths and guide accuracies is ensured and any canting of the iV disks (3.sub.j) is avoided.

6. The R718* compressor according to claim 5, wherein the guide support surfaces (F.sub.F) are related to a central guide diameter ØDF as well as a uniform application of force via the movement control devices (5.sub.j) per iV disk (3.sub.j).

7. The R718* compressor according to claim 1, wherein the iV disks (3.sub.j) are positioned for respective working/operating point in such a manner via the movement control devices (5.sub.j) per iV disk (3.sub.j) that the R718* compressor is operated with the lowest energy expenditure.

8. The R718* compressor according to claim 1, wherein with the rotor profile length L.sub.R the length L.sub.iV of the iV disks (3.sub.j) is designed in such a manner that at least first working chambers on the compressor inlet (1.1) always remain closed.

9. The R718* compressor according to claim 2, wherein the position pins take over both the exact positioning per iV disk (3.sub.j) and also during displacement of the iV disks via the movement control devices (5.sub.j) the guidance and entrainment thereof.

10. The R718* compressor according to claim 1, wherein the gaseous conveyed media is water vapour as R718 refrigerant.

11. The R718* compressor according to claim 1, wherein the gaseous conveyed media is an aqueous solution.

12. The R718* compressor according to claim 1, wherein the planar surfaces P.sub.F are perpendicular to a neutral axis A.sub.N.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The invention will be explained in detail hereinafter with reference to the appended figures. In the figures:

[0039] FIG. 1 shows a sectional view through an R718* compressor with iV disks completely in place;

[0040] FIG. 2 shows a sectional view through an R718* compressor perpendicular to a neutral axis;

[0041] FIG. 3 shows a detailed enlargement of an R718* compressor;

[0042] FIG. 4 shows a sectional view through an R718* compressor with a first displaced iV disk;

[0043] FIG. 5 shows a sectional view through an R718* compressor with several displaced iV disks; and

[0044] FIG. 6 shows a sectional view through an R718* compressor in which all the iV disks are displaced.

DETAILED DESCRIPTION OF THE INVENTION

[0045] The gas conveyor external thread per spindle rotor (2) is shown as a shaded area under the designation “ANGLE” according to the AutoCAD drawing software (i.e. at 45° two lines in each case, at right angles to one another, always arranged in alignment).

[0046] FIG. 1 shows as an example a sectional view through the R718* compressor when all the iV disks (3.sub.j) for 1≤j≤n where n is the number of these iV disks (3.sub.j) with a width b per iV disk (3.sub.j) are completely in place so that the maximum iV value for the corresponding compressor design is effective. Thus, as the gas fluid flow (G) there is only the outlet G.sub.oS via the gas conveyor thread of the spindle rotor pair (2). The number n of iV disks (3.sub.j) is determined according to the respective requirement profile in use of the R718* compressor wherein it holds that: the more iV disks (3.sub.j) are implemented, the more finely the actually effective iV value can be gradated, wherein the width b.sub.j of the respective iV disks should be taken into account.

[0047] In addition, as an example, planar surfaces P.sub.F are additionally plotted as dashed lines preferably perpendicular to the neutral axis A.sub.N. In order to avoid canting during movement of the iV disks (3) as reliably as possible, additionally as an example, guide support surfaces F.sub.Fz are shown centrally to the neutral axis A.sub.N relative to ØDF.

[0048] FIG. 2 shows as an example, a sectional view perpendicular to the neutral axis A.sub.N at a planar surface P.sub.F with cross-hatching. In addition, the preferably central guide support surfaces F.sub.F per iV disk are shown giving ØDF and the position pins (4) in pairs per iV disk for the exact positioning of each iV disk with respect to the spindle rotor pair (2).

[0049] Various positions of the iV disks (3.sub.j) for easy realization of different iV values according to the invention are shown in the following diagrams of FIG. 3 to FIG. 6, wherein for clarity only one side is shown, preferably executed as a mirror image to the neutral axis A.sub.N.

[0050] The exemplary sectional view of FIG. 3 as a detailed enlargement of FIG. 1 under the title “iV.m” shows the so-called “closed” position when all the iV disks (3) are completely in place by the movement control devices (5) being set to B.sub.Sg and therefore the maximum iV value is effective. Thus, only the gas flow G.sub.oS leaves the R718* compressor via the gas conveyor thread. The pressure ratio is then p.sub.2.H at the compressor outlet (1.2) divided by p.sub.1* at the inlet (1.1).

[0051] The exemplary sectional view of FIG. 4 as a continuation of FIG. 3 under the title “iV.n1” shows a position during displacement of the first iV disk (3.1) in that at the control device (5) for this iV disk (3.1) the motion control B.sub.Si for a desired intermediate position of this iV disk specifically sets the displacement distance s.sub.i with 0<s.sub.i<s and thus for the first time the maximum iV value from FIG. 3 is undershot, i.e. when the first iV disk (3.1) leaves the “closed” position. When viewed from the compressor outlet (1.2) the first iV disk is counted as the first iV disk (3.1). In this position the gas flows G.sub.o1 and G.sub.o2 as well as G.sub.oS leave the R718* compressor. Unlike in FIG. 3 the pressure ratio is then p.sub.2.N1 at the compressor outlet (1.2) divided by p.sub.1*.sup.o at the inlet (1.1) at the corresponding vaporizer or liquefier temperatures.

[0052] The exemplary sectional diagram of FIG. 5 as a continuation of FIGS. 3 and 4 under the title “iV.nj” shows an arbitrary position during the displacement of several iV disks (3.sub.j*) with 1 ≤j*≤n for n as the number of iV disks, whereby at the control devices (5) for these iV disks (3.sub.j) the movement control B.sub.Si specifically sets the displacement distance s.sub.i where 0<s.sub.i<s for a desired intermediate position of these iV disks (the plural is important) and thus each application-specific desired intermediate value for the currently effective iV value is achieved.

[0053] In this position the gas flows G.sub.o1 and G.sub.o2 as well as G.sub.oS leave the R718* compressor. Other than in FIG. 3 and FIG. 4, the pressure ratio is then p.sub.2.NN at the compressor outlet (1.2) divided by p.sub.1** at the inlet (1.1) at the corresponding vaporizer or liquefier temperatures.

[0054] The exemplary sectional view of FIG. 6 as a continuation of FIGS. 3 and 4 and 5 under the title “iV.L” shows the position of the minimum effective iV value whereby all the iV disks are displaced by their complete displacement path per movement control B.sub.So for the open position.

[0055] In this position the gas flows G.sub.o1 and G.sub.o2 as well as G.sub.oS leave the R718* compressor. Other than previously the pressure ratio is then p.sub.2.L at the compressor outlet (1.2) divided by p.sub.1*′* at the inlet (1.1) at the corresponding vaporizer or liquefier temperatures.

REFERENCE LIST

[0056] 1. Compressor housing having an inlet side (1.1) with pressure p.sub.1 and an outlet side (1.2) with p.sub.2 with a neutral axis A.sub.N as angle bisector to the axis AR as axis of rotation [0057] 1.1 Compressor inlet side during operation with the pressure p.sub.1 at a vaporization temperature t.sub.0 and at the same time forming the vaporization space [0058] 1.2 compressor outlet side during operation at the pressure p.sub.2 at a condensation temperature t.sub.C and at the same time forming the condensation space [0059] 2. Spindle rotor pair preferably with two-teeth mirror-symmetrically identical and multistage gas conveyor external thread and per spindle rotor with an axis of rotation A.sub.R at the angle γ with respect to one another and the neutral axis. [0060] 3. iV disks at a desired area of use having the width b.sub.j per iV disk (3.sub.j) with index j where 1≤j≤n and n is the number of iV disks with n≥1. [0061] 4. Position pins, preferably also with guide length and entrainment function. [0062] 5. Movement control devices per iV disk (3.sub.j), preferably operated with water hydraulics.

LIST OF SYMBOLS

[0063] ØDF Central guide diameter with respect to the neutral axis A.sub.N for iV disks (3) [0064] A.sub.N Neutral axis as angle bisector of both axes of rotation A.sub.R with the angle γ with respect to one another in mirror-symmetrically identical spindle rotors [0065] A.sub.R Axis of rotation per spindle rotor or also so-called central line [0066] F.sub.F Guide support surfaces for preventing canting of the iV disks (3.sub.j), preferably designed as circular segments (in order to save material) [0067] F.sub.F Guide support surfaces centrally to the neutral axis A.sub.N with ØDF [0068] P.sub.F Planar surfaces between the iV disks in the case of planar abutment thanks to shiny smooth contact surface (preferably ground) acting in a sealing manner to the adjacent iV disk, shown as a dashed line for example in FIG. 1 [0069] G Gas fluid flow [0070] G.sub.in with index “in” at the compressor inlet [0071] G.sub.o with index “o” at the compressor outlet, divided by means of displaced iV disks into [0072] G.sub.o1 outlet between the iV disks [0073] G.sub.o2 outlet via the spindle rotor heads [0074] G.sub.oS outlet via the gas conveyor thread of the spindle rotor pair [0075] B.sub.S Movement diagram as positioning arrows for the respective iV disk (3.sub.j) at the relevant movement control devices (5) shown as [0076] B.sub.Sg movement control for closed position of the respective iV disk [0077] B.sub.Si movement control for any intermediate position of the respective iV disk [0078] B.sub.So movement control for the open position of the respective iV disk [0079] b.sub.j Width of the respective iV disk (3.sub.j) [0080] s.sub.i Displacement distance for the respective iV disk with 0<s.sub.i≤s [0081] L.sub.R Spindle rotor profile length [0082] L.sub.iV Length of all iV disks