FR2538464A1 - SPIRAL TYPE MACHINE - Google Patents

Abstract

The invention relates to machines of the spiral type, more particularly for compressing gaseous fluids. Instead of using the conventional Oldham seal in this type of machine, the invention uses a device 126 for very simple control of the rotation of the spiral 52 in orbit with respect to the fixed spiral 50, which does not eliminate not the relative rotation, but simply limits it to a relatively small value, in combination with techniques for easily modifying the outline of the spiral windings to accommodate this limited relative rotation. Application to compressors, pumps, etc. (CF DRAWING IN BOPI)

Description

1. The present invention relates to an apparatus for

  fluid displacement and, more particularly, a

  China's advanced spiral type which is special-

  adapted to the compression of gaseous fluids, as well as a method of manufacturing this apparatus. There is a category of machines in the art

  called a "spiral" device for moving di-

  These types of fluids can be an expan-

  a displacement motor, pump, compressor, etc. and most of the features of the present invention apply to all such machines.

  for purposes of illustration, the embodiments described above

  The data will concern a gaseous fluid compressor.

  In general, a spiral apparatus comprises two spiral windings of similar configuration, each mounted on a separate end plate so as to define a spiral element. The two spiral elements are assembled together with one of the coils. moved in rotation of 180 relative to the other The apparatus works by putting in orbit 2. one of the elements in Spitri speii eae d'çrbite ")

  relative to the other element ("fixed spiral") in such a way

  re to create contacts by moving line between the flanks of the respective windings defining crescent-shaped insulated fluid pockets, the spirals generally have the form of involutes of circle, and ideally there is no relative rotation between the elements in spiral during operation, that is,

  say that the movement is purely a translation cur-

  viligne (that is, there is no rotation

  of a line in the body) The pockets of fluid

  the fluid to be treated from a first zone of the appa.

  spiral coil o is provided a fluid inlet to a second zone of the apparatus ot is provided a fluid outlet The volume of a sealed pocket varies during its movement from the first zone to the second zone at any time, there will be at least one pair of waterproof pockets, and when there are several pairs of waterproof pockets at one

  moment, each pair will have a different volume

  In a compressor, the second zone is at a pressure greater than that of the first zone and is physically located in the center of the apparatus, the first

  zone being placed on the outer periphery of the apparatus.

  Two types of contact define the fluid pockets formed between the spiral elements: the tangential line contacts extending axially between the

  spiral faces of windings caused by radial forces

  ("flank seals"), and surface contacts caused by the axial forces between the planar side surfaces (the "ends") of each winding and the opposite end plate ("end seal"). yield is high, a good seal must be

  obtained for both types of contact; however, the present

  the invention concerns especially the tightness of the flanks.

  In a conventional spiral compressor (that is, a 3 '

  compressor in which the windings are devel-

  circular flaps), good flanking requires that there be no relative rotation between the spirals. Spiral devices are generally described in US Patent No. 801,182. Parmiles Other Later Patents who describe

  spiral compressors and pumps are listed

  United States of America No. 1,376,291, No. 2,475,247; Nos. 2,494,100, Nos. 2,897,989, 2,841,089, 3,601,119, 3,600,114, 3,802,809, 3,817,644 and 3,884,599.

  Nos. 4,141,677, Nos. 4,300,875, 4,304,535 and 4,357,132.

  The concept of a spiral type device is

  known for a long time and has significant advantages.

  For example, the spiral machines have a high isentropic and volumetric efficiency, and therefore are

  relatively small and light for a given capacity.

  They are quieter and less prone to vibration than many compressors because they do not use large moving parts (eg pistons, rods, etc.), and like all

  fluid flows in a direction with a similar compression

  multanially in a plurality of opposed pockets, there is less pressure-induced vibration, such machines

  also tend to be highly reliable and

  because of the relatively small number of moving parts

  the relatively slow speed of movement between the spirals and the inherent absence of contamination by the fluid, however, despite this it is believed that the

  reason why the spiral machines of the prior art

  have not known until now very wide employment is

  due to the difficulty of manufacturing such machines,

  if only to the inherent problems of sealing and unusual wear.

  One of the most difficult areas of

  of a spiral machine concerns the technique used

  4 e yee to avoid relative angular movement between the spirals during their movement into orbit one

  compared to the other One of the most common solutions

  rants lies in the use of a Qldham seal between the orbiting spiral and a fixed part of the apparatus A Oldham seal typically includes a ring

  Oldham and two sets of keys or sliding blocks.

  The Oldham ring has on one side 8 grooves which are perpendicular to similar grooves in the other side. A set of keys is connected to a surface of the orbiting spiral and is disposed in the grooves on one side of the groove. Oldham ring, while the other set of keys is attached either to the fixed spiral or to the machine housing and is arranged in the grooves on the other side of the Oldham ring, The Oldham ring is

  animated by a movement of parallel to the grooves

  res containing the set of keys fixed to the spiral

  xe or casing The seal of Oldham acts thus as means

  control (that is to say, to avoid) of the

  angle of the spiral in orbit with respect to

  the fixed spiral, a concept that is thought to be essential

  the successful operation of a conventional spiral apparatus. US Pat.

  4,121,438 discloses a machine having this construction.

  Unfortunately, a spiral apparatus using an Oldham seal has several disadvantages as to assembly, operation, and maintenance, due primarily to the large number of parts constituting the seal. This large number of parts increases the costs of

  materials, manufacturing, and assembly O The blocks

  Smoothers or the keys of an Oldham seal are all also sliding elements inside the grooves of the Oldham ring, which presents problems of lubrication and wear, The ring animated with a movement of va-and -vient is also impossible to balance by inherence

  There are other devices known for

  to dictate the relative rotation of spirals, such as the use of multiple controls to rotate two spindles around different centers, and analog concepts

  guages; however, because of their complexity, these provisions

  Many of the characteristics of the Old Sam seal are also present in the present invention.

  1 different meaning The basic concept of the present invention

  tion is the use of a very simple device for controlling the rotation of a spiral in orbits, which

  does not eliminate the relative rotation, but the simple command

  relatively small amplitude, in combination with techniques for easily modifying the spiral winding contour to account for the limited relative rotation of the spirals

  occurring, in order to maintain a contact of

  the flanks between windings, three different versions

  of the rotation control device are described.

  each of which is a simple link connected in a way

  active between the spiral in orbit and a fixed part of the compressor Two embodiments include

  four-bar linkages and two additional modes

  All crank and slide assemblies All versions proceed to a coupling of the spirals in orbit and fixed; in a predetermined 9-minute relationship for all relative positions as the in-orbit cycle moves relative to the fize spiral. The control linkage of the rotation of the orbiting scroll in accordance with the present invention overcomes the disadvantages. cited above $ techniques

  of the prior art in carrying out this function.

  As the number of pieces is smaller, the manufacturing

  is less expensive and assembly much easier.

  The problems of lubxificat Qn are also reduced to a minimum because of the large size of the $ ns and, in one of the realizations, because the links are of the pivotally In addition, the antrotation element does not contain any vibrating ring in a reciprocating motion, so as to take account of the degree of rotation of the spiral in orbit. invention uses one or the other of two unique techniques for modifying the contours of winding a spiral,

  these two techniques are very easy to implement.

  and provide a very effective sealing of the flanks

  (one of them provides a watertightness of the theoretical flanks-

  perfect combination) when used in combination with the linkage arrangements listed above,

  new winding machining process is also

  seen. The compressor of the present invention also has an improved drive means for spiral orbiting, which is compact while being of simple fabrication and mounting.

  two embodiments are described.

  crits, provides the necessary contact between spiral windings for effective sealing of windings

  while providing an automatic function of de-

  load in case of bubbling or the like, In the case o

  a non-compressible fluid would be sucked into the compres-

  However, the radius of the orbiting spiral movement would automatically be reduced to allow the escape of this fluid between the spiral windings to a pressure zone (i.e. will run on the liquid), This function is performed without any additional parts, such as valves or

  smoothly, the training medium is also

  inside the crankshaft upper bearing, which makes it possible to reduce the axial height of the machine and to reduce vibrations,

  The compressor of the present invention incorporates

  also an improved thrust bearing arrangement which takes into account the axial load of the spiral in

  orbit This stage benefits from the inherent movement of rota-

  spiral in orbit to create a film

  compression which provides an oil support for the

  The bearing thus obtained provides a significant friction -

  lower than conventional bearings with

  The ball bearings, particularly those with relatively small balls, have such a punctual load that they tend to be subject to the same degree of wear. to wear

  The bearing of the present invention is also

  relatively inexpensive, of a very simple design.

  ple and of easy manufacture and assembly.

  The present invention will be well understood when

  the following description made in connection with the drawings

  attached in which Figure 1 is a vertical sectional view of a refrigerant compressor according to the present invention; FIG. 2 is a vertex of a portion of FIG. 3 of line 3-3 of FIG. 4 of line 4-4 of FIG. 5 of line 5-5 of FIG. Fig. 7 is a partial plan view of the compressor illustrated in Fig. 1, is a sectional view taken along line li is a view Fig. 1;

figure 4-

  Fig. 8 is a sectional view taken along section taken in sectional view taken along the line taken along the line 7-7 of Fig. 6; Fig. 8 is a an exaggerated illustration of the drive means for placing in orbit of FIG. 6 in its normal driving position; Figure 9 is a view similar to Figure 8 but showing the drive means in its position off load; Fig. 10 is a sectional view taken along the line 10-10 of Fig. 1; Fig. 11 is a sectional view taken along the line 11-11 of Fig. 1; Fig. 12 is a bottom plan view of the stationary upper spiral element; Fig. 13 is a top plan view of a lower vertebral element rotating in orbit;

  Figure 14 is a view similar to the

  Fig. 4 showing a second embodiment of the rotation control means of the present invention; Fig. 15 is a partial horizontal sectional view of a third embodiment of the rotation control means of the present invention; Figure 16 is a view similar to the figure

  a fourth embodiment of the control means

  of rotation of the present invention; Fig. 17 is a partial horizontal sectional view of a second embodiment of a drive means of the present invention in its normal driving condition; Figure 18 is a view similar to the figure of the drive means in a hor chaerge position; Fig. 19 is a schematic representation of an embodiment of a pair of paired spiral windings according to the present invention; Figures 20A, 20B, 21, 22 and 23 are

  diagrams of the geometry of the present invention.

  feeling the nomenclature used; and 9 ',

  Figure 24 is a schematic representation of

  An apparatus suitable for use in the practice of the machining method of the present invention is described. In connection with FIG. 1 there is shown a refrigerant compressor, described by way of example,

  of the hermetic type according to the present invention, the compres-

  is located inside a hermetic enclosure

  consisting of an outer casing 10 and a casing

  lower loppe 12 which are welded together from the

  usual way for example at 14, fixed at the bottom of the en-

  lower belt 12 is a plurality of feet 16 which has been shown a copy, the assembly comprises a motor 18 attached to a crankshaft 20 whose upper end drives a compressor 22 of the spiral type,

  an oil pump 24 being driven by the lower end

  crankshaft 20 in order to ensure the lubrication

  Machine Application The lower envelope 12 includes

  a housing containing lubricating oil, the upper level of which is represented at 26,

  The engine-compressor assembly comprises a housing

  lower housing 28 enclosing a bearing 30 in which the lower end of the crankshaft 20 is supported and rotatably mounted, and an upper bearing housing 32 which defines a bore 33 in which spaced sleeve bearings 34 and 36 are disposed which

  rotate the upper end of the crankshaft

  The bearing housings are fixed to each other by means of a plurality of threaded fasteners

  38 which fix the stator 40 of the Engine 18 Fixed to the

  brequin 20 and disposed within the central bore

  The rotor 40 is a rotor 42. The motor is in all respects conventional in design and operation. The compressor assembly is mounted within the lower casing 12 by means of a plurality of rods. (A rod is shown) which are screwed into the lower housing 28 and bolted to the bottom of the lower casing 12 in a way that is best represented at 46, leaks from the envelope,

  They are avoided by an O-ring 48 in contact with

  The compressor, per se, comprises a fixed upper spiral element 50 and a lower orbiting spiral element 52 having a flat bottom face 53 and a drive hub 54. extending downwardly which is disposed inside a bore 56 placed eccentrically in the upper end of the crankshaft The end of the hub 54 has a recess 55,

  An upper counterweight 57 is provided on the crankshaft

  20 at a location adjacent to the bore 56 to facilitate balancing of the eccentricity of the crankshaft control comprises a lower counterweight 59 fixed in a continuous location at its lower end to complete the balancing system according to principles

  known The fixed spiral element 50 is located at a distance of

  predetermined accuracy above the surface

  this planar upper 58 of the housing 32 of the upper bearing by means of a spacer ring 60, and bolted to the

  housing 32 by means of a plurality of rods 62 which serve

  also wind to fix the spacer ring 60, the end

  upper part of each rod 62 is projecting into a

  tretoise 64 made of nylon material which is arranged in the

  interior of a cup-shaped element 66 attached to a ban

  assembly 68 welded to the top of the upper envelope

  re 10 Q In this way, the upper part of the whole

  4 compressor motor is mounted on the top of the enve-

  Although only one has been represented, a certain

  number of links of this nature are planned.

  The fixed spiral element 50 comprises a s-urfa-

  this flat end seal 70, from which

  there is a spiral coil 72 projecting therefrom. The spiral element 50 has a centrally located kidney-shaped discharge opening 74 which communicates with

  a delivery chamber 76 located at its upper end.

  The chamber 76 is covered with a valve plate 78 provided with a lining, which has orifices 79 and

  is held in place by a cylindrical head 80 b.

  The direction of the current in the orifices 79 is controlled by a conventional blade type stop valve 81 which is connected to the upper surface of the element 50 by means of a plurality of threaded fasteners 82. is fixed to the plate 78, together with a usual support element 83, by means of a rivet 85. The discharge fluid leaves the head 80 through an opening 84 which is disposed at one end of a discharge tube 86, The tube 86 extends over the top of the assembly in the down direction, between the latter and the envelope to a point where it exits the envelope in the conventional manner (not shown ) The aspirated gas is introduced into the casing in the normal way by

  via a connector 88 extending through the

  king of the upper envelope 10 o The engine setcomplifies

  The described here is of the "low side" type with the aspirated gas present in the hermetic envelope to cool the engine and the like. The gas enters the compressor 22 at the periphery of the spiral windings O The orbit winding 52 comprises a flat end sealing surface 90 from which

  is projecting a spiral winding 92 intended to ve-

  in sealing contact with the windings 72 during relative orbital movement of the spiral elements in the usual manner for the purpose of forming fluid pockets

  having a decreasing volume, the ends of the winding

  92 are intended to come into sealed contact with the

  surface 70 of the fixed spiral and the ends of the coil.

  72 are intended to come into sealing contact with the 12, surface 90 of the spiral in orbit. The central surface of the spiral 52 has a recess 94 in the form of

  in order to facilitate the circulation of the fluid

  The two windings 72 and 92 have the same conical sectional shape so as to maximize the metallic resistance.

  of the winding at its root, the opening of

  84 and the recess 94 have a shape that provides a maximum flow area without weakening the root of the contiguous windings. The surfaces 70 and 90 must be in planes which are parallel to the planes

  in which are the ends of the two windings

  and which are perpendicular to the axis of rotation of the crankshaft 20

  The training means of the present invention

  tion does not use rigid coupling between the city and

  brequin and the spiral in orbit, but on the contrary is of the type that flexes radially so as to allow automatic discharge of the compressor in case of incompressible fluid inlet or misalignment of parts The driving means is based on centrifugal and driving forces to keep the flanks of the spiral in orbit in tight contact with those of

  the fixed spiral This is obtained in a very compact way

  in the axial direction using an unloading hub 100

  this is best represented in Figures 1 and 6 to 9 '.

  The hub 100 includes an outer circular cylindrical retainer 102 and axially spaced inner sleeve bearings 104 and 106 in which the hub 54 of the orbiting scroll is mounted. The retainer 102 has a flat driven surface 108 on its periphery, the surface 108 being in a plane parallel to the axis of rotation of the crankshaft, the driven surface 108 being in motor contact with a

  complementary flat drive surface 110-of the

  king of the bore 56, the latter surface having a

  The bore 56 is also of sufficient shape and size to allow limited relative tangential sliding between the hub 100 and the crankshaft 20. The center of rotation of the crankshaft is shown in Fig. 13, which is larger than the first. in cc and cent

  the hub and the spiral in orbit in cs, the rota-

  The crankshaft 10 causes the hub 100 to rotate about the DC axis. This, in turn, causes the hub 54 to be orbited, and hence the element 52 about the DC axis. orbit of the element

  spiral is determined by the geometry of the profiles of

  bearing (that is, the contact of the flanks

  elements of the spiral element in orbit with the flanks

  windings of the fixed spiral element).

  In the case where the windings meet a

  incompressible fluid, the forces created that tend to separate them will be supported by the hub

  sliding between the normal position of

  The flow shown in FIGS. 6, 8 and 9, and the exaggerated position shown in FIG. 9 will allow the windings to separate and pass over the fluid plug, whereupon the centrifugal force will cause

  the return of the winding in orbit to its contact with

che with the fixed winding.

  The relationship of the parts in their axial assembly minimizes the axial height of the assembly In addition, it allows to position the upper counterweight very close to the center of the mass of the spiral in orbit, which has the effect of reducing the bearing loads and the bending forces acting on the crankshaft, as well as the size of the counterweight required It also allows

  cantilever control support at the top of the city.

  brequin, which has the effect of further reducing:

acting on the bearings.

  The present invention presents another version 14, unique of an orbiting control means which will also give the desired orbiting movement while allowing an automatic unloading of the compressor in case of presence of incompressible fluid, this embodiment shown in horizontal section in

  17 and 18 comprises a crankshaft 112 (having a center

  rotation cc) in the upper end of which

  is disposed an axial bore 114 having the illus-

  the important part of this bore being an over-

  circular cylindrical face 115 (having as a radius center cp), in which a hub 116 which comprises

  a projection 117 having a radius equal to that of the sur-

  The hub 116 has a circular bore 118 (having an axis cs) in which the hub 54 of the orbiting scroll is mounted. Suitable bearings may be provided at the interface of the bore 118 and the hub 54, where appropriate. As can be seen, the geometry of the arrangement is such that, upon rotation of the crankshaft 112 about the axis dc, the centrifugal force will normally maintain the respective portions in the positions shown in FIG. of

  the orbit controlled by the geometry of the flanks of spira-

  as previously described In case of unloading

  the hub 116 can rotate around the center cp to the position shown in FIG. 18, so as to allow the winding flanks to separate into

  the measure necessary for the passage of incomprehensible matter

  The present invention solves the problem of coupling the spiral elements for the control of the relative movement between them of a very simple and unique manner. In the embodiment of FIGS. 1 to 13 (see especially FIGS. Figures 1, 4 and 5), this

  is obtained by providing a projection 120 on the periphery.

  outside the spiral element in orbit 52 which

253,464

  15. has an axially extending bore 122 in which a projection 124 is pivotally mounted at one end of a single link 126, the opposite end of which is pivotally mounted to a fixed part of the apparatus; As shown, the link 126 is mounted on axially extending locating pins 128 which protrude into and out of the member 50 and are positioned with respect to this member 50 and the housing 32 of the upper bearing. The lower surface of the link 126 is flat and slidably rests on the flat upper part of the spacer ring 60.

  The link 126 is preferably as long as possible (so as to minimize the effect of the fact that the protrusion 124 will move in an arc-shaped path and not in a straight line, and should operate as close as reasonably possible perpendicular to an imaginary line extending between the center of the element in orbit and the bore 122 '

  very simple linkage arrangement replaces the coupling

  complex Oldham seal used in the devices

  The small degree of relative rotation between

  spiral arrangement that this linkage arrangement allows is precisely controlled and is of an amplitude and

  defined so that it can be easily obtained

  The embodiment of the present invention also includes other simple linkage arrangements such as those shown in FIGS. 14-16. The embodiment of FIG. 14 is almost identical to FIG. that of Figures 1 to

  13 except that the single link is relatively straight

  as represented at 130, and is mounted at its end.

  fixed on a protrusion 132 on a support 134

  10, the movable end of the rod 130 is in all respects the same as that described in connection with the previous embodiments and the operation of the two rods is the same These two linkage arrangements are known in the art in the form of four-rod linkage The first "bar" of the linkage is the link 126 or

  which extends from a fixed part of the structure

  to the periphery of the spiral in orbit

  second "bar" of the linkage is the imaginable link

  between the pivot point on the periphery of

  the spiral in orbit and the geometric center of the spira-

  The third "bar" is the imaginary link that extends between the geometric center of the spiral and the

  center around which the spiral is in orbit, and the

  third "bar" is the fixed structure that extends between the fixed pivot of the first bar and the fixed pivot of the

third bar.

  The embodiments of the rotation control means shown in FIGS. 15 and 16 are both

  of the crank and slide type In the embodiment of

  In FIG. 15, the projection 120 of the orbiting element 52 has an elongated slot 136 which extends radially and is slidably disposed therein.

  an axis 138 which is mounted on a support 140 fixed rigidly

  to the upper envelope 10 O In the embodiment

  In FIG. 16, the projection 120 of the member 52 includes an axis 142 which is slidably disposed within an elongated slot 144 extending radially in a holder 146 attached to the upper envelope 10.

  In these two embodiments, the rotation of 1

* in orbit is avoided as a result of the interengagement of the axis 138 in the slot 136 or axis 142 in

the slot 144.

  Thus, in the four embodiments,

  the rotation of elements in orbit is avoided by

  around a single pivot point relative-

  The first important difference between the arrangements is that in the four bar linkage arrangements the single pivot moves in a slightly arcuate path, whereas in both the rod and slide arrangements the motion relative pivoting is effected along a path rec

  Moreover, in the embodiment of FIG.

  15, the imaginary link between the pivot point

  the geometric center of the orbiting spiral varies with orbit

  is fixed in the other embodiments.

  The treatment of high thrust loads which is an inherent feature of a machine

  spiral, is an area that has raised a lot of

  The plaintiffs have discovered that these thrust loads can be effectively treated.

  using a turnover that is based on the imbalance

  inherent feature of the spiral element in orbit to

  carry the thrust load through a compression film mechanism This bearing has a very low friction, is of a very

  simple, requires only a flat finish, has a high rigidity

  and the relative velocities encountered are relatively small, has shear losses of

  low value Ii also transmits the loads of

  directly to the frame of the apparatus (ie

  housing 32 of the upper bearing).

  As best seen in FIGS. 1, 10 and 11, the assembled thrust bearing comprises a bearing 150 which is relatively sparse, made of teflon material and bronze impregnated with lead or other material.

  appropriate with flat and parallel opposing faces

  in sliding contact on its underside with the surface

  upper flat 58 of the casing 32 and on its upper side

  with the flat surface 53 of the element 52 The relative movement 18 between the bearing Q and the element 52 is prevented by an axis 152 which projects into the two parts There is no groove oil on the bearing 150, but the upper surface 58 of the housing 32 has two concentric rings 154 and 156, the groove 156 is an oil feed groove and is fed with oil.

  via a plurality of channels 158 which communicate to.

  through the housing 32 with the bore 33 in the space between the bearings 34 and 3 6 groove 154 is an oil drain groove which allows the oil to

  return to the open crankshaft defined by the log-

  32 via a plurality of channels 110, for the purpose of

  reduce the transfer of oil into the sucked gas

  The surfaces 53 and 58 must be parallel to each other and perpendicular to the axis of rotation of the crankshaft 20. It is thought that this bearing functions because the inherent tilting or trembling of the -spiral in orbit during its motion creates a rotating oil wave that runs through the entire face of the

  bearing at a speed determined by the rotation speed

  Therefore, if the engine is running at a speed of 3600 rpm, the relative axial speed of the parts will cause this wave to cross the crankshaft.

  the entire bearing face 150 and surface 58 followed by

  a circular path at a speed of 3600 rpm

  per minute A standard hydrodynamic

  would not, it is thought, be in a correct way because there is not enough relative movement (ie a sufficiently high tangential velocity) between the spire and the housing as it is only a question of an orbital movement with a relatively small displacement,

  Since the bearing of the present invention utilizes a

  relatively large flat face, the unit load is relatively small and a long service life of the pan 19-,

linking is therefore possible.

  The thrust loads encountered at the extreme

  The elements of the spiral-in-orbit element are supported by the axial interengagement of the two spiral elements 7 specifically the contact of the ends of the windings of a spiral element with the end surface of the spiral. cheekiness of the other spiral element The fasteners 62 ten + tooth urge the spiral elements in the direction

  axial to bring them together and the fluid pressures pro-

  driven by the operation of the compressor have

  It is desirable to have an axial force sufficient to urge the spirals towards each other, or to maintain them in a sufficiently close relationship, so as to obtain a tight seal.

  On the other hand, it is desirable to minimize

  to the extent possible, friction and wear,

  In the present compressor this wear of the ex-

  tremities is controlled by substantially increasing the

  At the end of the outer winding of each spiral element, as best seen in FIGS. 12 and 13, it is well known that the outer flank on the outer 180 of each spiral winding

  is not used in the cycle of compressions It is -

  advantage of this fact in the compressor of the present invention to control the wear of the ends, as can be seen in FIG.

  1800 of winding 72 have a greater thickness than

  than the rest, starting at reference 17 Q and ending

  minus at reference 172, This surface passes neck "

  lissement on the surface 90 of the element 52? Lubricating oil

  The invention is provided at the interface via a channel 174 in element 52, which in turn receives oil from a vertical channel 178 communicating with the space between bearings 104 and 106 via a canal

  radial 180 (Figures 7 and 13) The outer end of the body

,

  nal 176 is clogged in the usual way.

  13, approximately the last 1800 of the winding 92 also have a much greater thickness than that of the rest of the winding. reference 182 and ending with the reference

  184 Moreover, the enlarged part of the winding

  a groove 185 which receives the oil from a channel 186 communicating with the channel 1761.

  of these relatively large surfaces reduces the

  in the axial direction and therefore the wear of the outer ends. The lubrication of the respective parts of the machine is carried out using the oil pump 24 which is driven mechanically by the crankshaft and presses to pump pressurized oil between the casing at the bottom of the casing, which is broadly outlined. by reference 200, and all moving parts of the machine requiring lubrication, the oil pump

  24 may be of any suitable type in accordance with

  dance with known criteria; however, by way of example, it may be of the type shown in US Pat. Nos. 4,331,420 or 4,331,421, which will be assumed to be known herein. The pump inlet is shown in FIG. and its exit is via an oil channel 204 extending vertically to the center of the crankshaft 20 As best seen in FIGS. 11 6 and 7, the upper end of the channel 204 communicates with a transverse channel 206 of the crankshaft, whose ends

  opposite channels communicate with channels 208 and 210 extend

  3 Q uant vertically, The radially outer end of channel 206 and the upper ends of channels 208 and

  210 are plugged in the usual way, Channel 208 com

  communicates with a channel 212 extending radially, which plane the space between the bearings 34 and 36 in communica,

  with a lubricating oil supply under pres-

  The channel 210 communicates with a generally radially extending channel 2, 14 which communicates with the interface of the surfaces 108 and 110 and a channel 216 extending radially into the hub IQO to place the space. separating the bearings 104 and 10 E in communication

  with a diet in oil; pressure lubrication.

  The lubricating oil is conveyed from the space between the outer pair of bearings and the thrust bearing via a channel 158, as previously described, and from the space between the inner pair of bearings and the end surfaces. spiral pairs via channels 180, 178, 176, 174 and 186, as previously described. As the lower counterweight 59 is disposed below the level of the oil sump (as a result of the size of the counterweight required to balance

  the relatively large eccentric mass of spira-

  in orbit), it is planned to prevent the rotation of the

  the counterweight pumping the oil and

  they consume energy unnecessarily, This is achieved

  se forming a recess 220 in the lower housing 28 which has a surface very close to the outer surface

  counterweight 59 during its rotation.

  The chamber 220 communicates with an oil outlet line 222 which extends radially outwards and then upwards between the housing and the casing. When the compressor starts, the rotation of the counterweight 59 will have the effect of that the oil will come out of the room 220

  by pumping via line 222 to enter the car-

  of the envelopes In order to allow this evacuation

  oil from chamber 2207 housing 28

  comprises a channel 224 communicating with one of its extremes

  with the central part of chamber 220 and its

  other end with a pipe 226 which extends

  above the level of the oil in the bottom of the housing, 22. This conduit allows the entry of gases or vapors in the chamber 220 when starting the compressor, o evacuation of the entire oil The excess oil

  at the top and bottom of the inner bearings with

  chon, at the top of the sleeve outer bearings and inside the mound bearings is brought back to the crankcase

via channels 217 and 218.

  Conventional spiral compressors with rolling contours that are involutes of a circle require curvilinear translation

  between the fixed and mobile spirals so as to

  keep a contact of the flanks line to line If the say, positive curvilinear antirotation is replaced by the

  linkage of the present invention, which allows a

  In order to maximize the effectiveness of the pivoting of the spiral into orbit, a certain means must be used to maintain line-to-line contact. Two techniques of this nature are described.

  the first is a shift technique of development

  The second is a modification technique that results in flank profiles that are not true involutes or are not involutes.

  flanks (that is, the distance between the rolls

  pairs of spirals) are extremely small when using the first technique The second

  technique gives distances with a theoretical leak-

  In general, compressors

  two or more spiral windings

  produced from the development of a geometry, sorted flat and mounted on base plates. If a generating circle is used, its radius is the thickness of the spiral rolling and the total number of The coils are selected to give the displacement volumetric and 23 the desired pressure ratio. When the spirals are rotated by 1800 and joined together so that the flanks and the ends touch each other, they form pockets O If a spiral is provided in such a way that move in a curvilinear translation (no rotation of a line)

  whatever in the body) compared to the other spira-

  the, the pockets are then sealed and move inward in the direction of the center or towards the outside in the direction of the ends of the spirals, according to

  the direction of rotation When there is a roll of

  Working pressure greater than 1.5, the fluid contained in the pockets will be compressed or dilated. If the movement is a true curvilinear translation, it will be obtained

  perfect sealing of the flanks (excluding irregular

  rites of the involutes surface) Because of the line

  relatively long sealing of flanks and ends

  Some games may provoke an effective

reduced.

  The techniques of my trie end games

  are not specifically the subject of the present invention.

  tion; those concerning the flanks are.

  For context, and in connection with the

  20 A, the equations describing the profiles of the develop-

  pants of spiral when the relative motion is a

  curvilinear translation and the rotary displacement

  tif between the generator axis (xy) of the spiral elements is 180, are: PR = C (l + (Ar, MT / C) 2) 1/2 Ar = Ac + Pi / 2 = A arctg (Ap) o R is the distance between the center of the cervix

  bse key and the profile point of spi-

  Rale, C is the radius of the generating circle of bam se. Ar is the angle of the bearings 24, T is the thickness of the spiral winding, M is a logical modifier M = 1 for the surface $ 1 and M = Q for the surface 521 Ac is the angle of c "Numerical band" which is incremented or can be considered as the angle of the crank when the contact occurs between the fixed spiral and the moving spiral in question

  Ap is the angle of the polar coordinate.

  The curvilinear translational motion neces-

  the use of an anti-rotation device such as the Oldham joint complex and relatively cotteux, A simpler and cheaper device is the arrangement to

  Rotatton control linkage previously described.

  However, this arrangement allows a slight pivoting of the spiral in orbit, which normally would cause the flanks to separate or interfere and reduce the efficiency of the machine By changing the geometry of the winding, this game or interference can be reduced The present invention incorporates two new profile modifications, which are as follows: It has been discovered that conventional circle expansions can be used with the

  linkage described above and excellent characteristics

  sealing of the flanks obtained by forming simple

  the profile of the inner development of a winding flank on a center of a base circle different from the external involute profile of the same flank,

  involute profiles are identical, but the wraps-.

  resulting in a thickness that varies along its length, the base circles of one or the other sidewall or the two inner and outer sides of one or the other or both of the spirals may be offset, three possible cases: (1) offset of the inner and outer profiles, on only the spiral fix (2) offset of the inner and outer profiles on only the spiral in orbit; (3) Offset of the inner and outer profiles on the two spirals, It has surprisingly been found that Case No. 1

  gave the best seal and the case N O 2 the seal = -

  the least acceptable This is based on a theoretical analysis; it is believed that in actual practice the leakage that could occur between matched flanks even in case 2 will probably be acceptable. A pair of such windings 250 and 252 is shown in exaggerated form in FIG. 19, which is a machine following the

  case n 1 in which the winding 250 is the winding

  in orbit and the winding 252 is the fixed winding

  and including all the corrections-.

  The geometry of the linkage mechanism of the present invention is shown in FIG.

  P = location of the pivot point of com-

  rotation of the spiral in orbit

  te (for example the axis of the protrusion 124), cs = location of the geometric center of the spiral in orbit, cc = axis of rotation of the crankshaft, L = distance between the geometric center of the

  spiral into orbit and the point P (ie

  say length of the imageable link

  in the orbit), Am = relative angle between spirals / 3 QB = angle between the start of the involute of the base circle in orbit and the center of the pivot axis (polar), E = eccentricity (radius the orbit of the spiral in orbit), V = angular velocity of the crankshaft, 26., Tm time, Si = sidewall profile,

52 profile of the outer flank.

  In order to conceive the spirals of the pre-

  In this invention, spira-

  those of classical form (as they would be used

  with a seal of Oldham) to obtain the

  the pressure ratio, and the geometry of the ori

  this output correct according to conventional methods.

  This results in known values for the C radius of the involute base circle winding thickness

  T and the number of windings of the outer surface.

  As soon as this calculation is done, we must choose the location

  point P, pivot point of the spiral in orbit.

  The distance between the geometric center cs and the point P is L For manufacturing purposes, the distance L is

  chosen to be convenient It must be

  than the distance between the geometric center of

  and the outside of the spiral if the pivot point

  P is on the lower side of the spiral element, but will preferably be outside the outer coil as shown in FIGS. 1, 4 and 13, since the end of the outer coil constitutes a point of convenient reference, for demonstration purposes, the pivot point P y will be located, although it could be at any other location around the periphery of the spiral. It will be noted that the length L represents the rod formed by The line between cc and cs is called the "line of centers". As indicated above, it has been discovered that there are a number of lattice mechanisms at the latch. basis that will achieve the goal that there is only one

  small controlled rotation between spirals

  to reduce the cost and facilitate the lubrication

27

  wise, the four-bar linkage is the solution

  preference if length L is sufficient

  the rod substantially perpendicular to the line extending between P and cc in FIG. 21, the movement of the four-bar linkage becomes similar to

  to that of the crank and slide embodiment

  bucket of figure 16 because the point P moves essential '

  along a straight line and the length L does not change

  This embodiment is therefore the easiest to analyze. The other mechanisms described

  will follow a similar analysis with results

lar.

  The basic problem, if we consider the

  re 21 is that the spiral in orbit will rotate according to

  Am while the eccentric moves the center of the spiral into orbit around the orbit circle with eccentricity E These angular excursions result in mismatching spiral surfaces, causing a simultaneous gap and interference situation at the sealing points between the flanks of the spirals, resulting in a loss of capacity and efficiencyo

  The value of the interstice and interference is

  the amount of mismatch between the spiral surfaces, which in turn depends on the geometry of the links and the configuration of the spirals, Suppose that P moves radially following

  a straight line passing through the center of the general circle

  the value of Am is then: _E sin (V Tm) Sin (Am) E sin (V Tm) L For low values of Am (which will be the case here) we can assume that : Am = sin (An) = sin (V Tm (radians) Am = if (Am) = L Therefore, as the maximum angle during the rotation 28 of the spiral in orbit relative to the fixed spiral is V Tm = 90 Q; Am max E / L (radians) If we look at Figure 21, when the center line nasses by a position, the value of Am is 0 Thus, there is a relative angle of zero between the spirals

  at this point, which means that there is no maladjustment

  However, as the line of the centers moves to point b, the value of Am increases to reach the value

  Am max, resulting in a maximum value of the disap-

  tation of surfaces If it is desired that the points of

  with the present linkage arrangement are at the same points as with an Oldham joint (ie with no relative rotation allowed), the profiles should be

  then be modified to allow it to be observed.

  Whereas at positions a and c, there is a relative angle O between the spirals and thus no radial correction is necessary. At positions b and d, where the relaxed angle tif between the spirals is maximum, the correction radial is maximum and equal to: R max = l (E / L) / 2 (Pi) l 2 (Pi) C = EC / L

  Between zero and correct correction points

  maximum correction, the radial correction will have a certain intermediate correction approximately equal to (EC / L) sin (V Tm) Thus, when the uncorrected spirals are in the position requiring a maximum correction, a set of sealing points has a Since the other set of sealing points actually requires interference, it has been found that these interstices and interferences can be corrected by an appropriate offset of the involute profiles in a direction perpendicular to a line passing through the centers despirales and a point 29-, of development P when the spirals are in

their position without rotation.

  If the correction or offset is to be applied only to a spiral winding (cases n P 1 and 2), the profile of the inside of the winding roll is then shifted in a direction along the normal line by an amount equal to R max so as to close the gap and eliminate the interference, and the outer profile of the winding is offset by the same amount in the opposite direction for the same

reason.

  When the four flank profiles are cor-

  In this case, a similar correction is made to the two spiral windings. More specifically, the inner profile of a spiral winding is decased in a direction along the normal line to close the gap and eliminate interference. the outer profile of the same winding is shifted in the other direction for the same reason The inner profile of the second winding

  is also off, but in the opposite direction to that

  the inner profile of the first winding, and the

  outer thread is offset in the direction opposite to that of the outer profile of the first winding The amount of the correction

  to-apply to each of the flanks of case # 3 is the following: Fixed spiral winding Spiral winding in orbit External flank Inner flank Inboard flank Inner flank (X) (Rmax) (y) (Rmax) (i-Y) (Rmax) (lX) (Rmax) where X is the proportion C% / l Qo 0) of desired correction on the outer flank of the spiral winding six and Y

  the desired correction proportion on the flank

  of the fixed spiral winding, so the correct

  the outer flank of the fixed scroll plus the correction of the inner flank of the spiral in orbit will give a total R max, as will the com- bined correction of the inner flank of the fixed scroll and the outer flank of the spiral in orbit, The result is a spiral or a pair of spirals having a winding which no longer has a uniform thickness. It will be seen in FIG. 19 that the winding of the fixed spiral 252, to which all the corrections have been applied at the same thickness to all crossing points of the x-axis, has a reduced thickness at all points where it intersects the y-axis below the x-axis, and has a greater thickness at all points where it

  cuts the y axis above the x axis So, while

  grind inward along a corrected spiral,

  the thickness varies continuously, having a maximum value

  mum, a minimum value, or a "nominal" value to

  the result is that the

  wires have a shape and a position during operation, such that they are extremely close to the tightness

  at all required points and at all times.

  As noted, the shift method of

  pante produces a small game or sidewall interference The size of this game or interference depends not only on the crank angle and the basic geometry of the game.

  the spiral, but also of the K report, a modification report

  addition to the fixed winding divided by the modification

  Therefore, assuming both

  spirals are modified in the same way if the modification

  total cation is added to the fixed spiral, K _ 1; whereas if total modification is added to the moving spiral, KQ, satisfactorily functioning compressors were constructed and tested with K = 0.5, a value originally thought to be optimum, however, a subsequent analysis revealed by surprise that the smallest error occurs when K = 1, while 31, the error is the greatest when KQ = This constitutes an almost linear relationship between the two so that the best value for K is 1, K may also have values greater than unity or less than OO but these values have no known advantage,

  In addition, as noted above, the same amount

  correction factor does not need to be applied to cha, that spiral In the case of unequal correction there will be different values of K for different flank interfaces in the same machine As used here the ratio K 1 represents the ratio K for the fixed and inboard outer flanks in orbit, and K 2 the ratio K for the fixed and movable inner flanks. Thus, the optimum situation (all

  corrections made to the fixed spiral)

  will dune when KI = 1 and K 2 = 11 which is the same as having K = 19

  Overall, potential theoretical errors

  the in the shifting process have three different origins: (1) sinus error; due to the approximation A = sin (A) (2) The error of the link arch When the length of the link is large enough, this error becomes very small; however, by planning in practice

  a condition that can be reduced

  This error can be totally eliminated by using a crank and a

slide.

  (3) The choice of the surface to be corrected By making completely the décqlage on the 1 spiral fixecette error is null, By carrying out entirely the offset on the spiral mobile, this error has its value 32 mx Rnr R, As it n ' There is no known advantage to shifting on the mobile spiral turn, it must be done on the fixed spiral, However, it is thought that in practice all these errors are negligible enough not to

  have a detrimental effect on the performances of the compres.

sor.

  Fig. 22 shows a flank contact

  the fixed and inboard outer flanks in orbit, and Figure 23 between the outer flanks in orbit and inner fixed These points are defined for given geometric parameters (C, T, L) and a certain position of the crank of the compressor (Ac ), The extra material that needs to be added or subtracted from the pros

  involute wire - for continuous contact between spi-

  was determined in accordance with the following: R Doc Doc C (1 + Do C 2) 1/2 = Ar + Kl (Am) Doc = Ar + (K 2 l) Am Doc = Ar + K 2 (Am ) T / C Doc = Ar + (K l l) Am T / C Ar = Ac + B + 5 (Pi) / 2 Ar = Ac + B + 5 (Pi) / 2 + Am Ar = Ac + B + 3 ( Pi) / 2 Ar = Ac + B + 3 (ft) / 2 + AM Outer surface Outer surface Inner surface Inner surface Outer surface Outer surface Inner surface Inner spiral surface fixed. spiral mobile spiral fixed spiral mobile spiral

fixed.

  mobile spiral. fixed spiral, spiral moving Ap = Ar arctg (Doc) limiting rod Am = B B

(4 bars 9,) -

  Bb = (see calculations in steps 3 of For a 33. the algorithm explained below) For a limiting slide (crank and slide with spiral axis): Am = arcsin (} E / Llsin (Ac) K 1 = Value of the modification added to the outside flank

  of the fixed spiral divided by the total change

  between the outer and the inner flanks

  le, K 2 = Value of the modification added to the inner flank of the fixed spiral divided by the total change between moving inner and outer inside flanks

Doc = Fictitious variable.

  Ac = "crank angle", although it is better to

  say increment angle of "match".

  B = angle from the beginning of the involute on the base circle in orbit and the center of the axis of

pivoting (polar).

  C = radii of the base generator circle.

* T - = Thickness of spiral winding.

  Ac increment starting with Ac such that Ar = O,

  Mw = number of windings = (Ar until the end of the spindle

Pi / 2) / 2 (Pi),

  Stop when Ac = 2 (Pi) (Nw) + Pi / 2.

  In Cartesian coordinates: X = C (1 + Doc 2) 1/2 cos (Ar arctg (Doc)) Y = C (1 + Doc 2) 1/2 sin (Ar arctg (Doc)) In numerically controlled milling machines , the

  Cartesian equations must be programmed to give

  Position coordinates, A possible algorithm is as follows; 1 If involute profile = inner surface then

Ac = B 3 (C Pi -?, 2 + Au.

  If involute profile outer surface then Ac = B 5 (Pi) / '2 + Au 2 If a limiting slide (crank and slide with 34, spiral axis) is used, then; Amn = arcsinl (E / L) sinr (Ac) l

Al ler at 1 step 7 ,.

  3 If a rod of friction C trin 9 Ierie at 4 bar) is used then Xa = (E) cos (Ac + B + Pi) Ya = (E) sin (Ac + B + pi) Xgb = Xa + (L) cos (R, + PI) xc = x coordinate of the projection center 124 (Fig. 4) Yc = y coordinate of the projection center 124 (Fig. 4) Az = ((Xc Xa) 2 + (Yc 2 O 'Yu = (Xa Xc) / Az Cc = arctg (Yu) Fll F 12 = i

  If (Ya Yc)> 01, then ps in step 4.

  Cc 2 (pi) -Cc F11 -1 4 Xum = Xc + Lk (coe (Cc))

  If Xgb -, Xumn <0, go to step 5.

F 12 = -12 2

Yu = (Az + Lik _ L) / 2 (Az) (Llk)

cb = (F 11) (F 12) arctg (Yu) -

  Xb = Xc + Lik (cos (Cc + Ci)) Yb Yc + Lik (sin (Cc + Ci)) Xgb = Xb Bbi arctg U Xa-Xb) / L) if Ya Yh> 0, go to step G Bb 2 (pi) -Bbi 6 Ain = B -Bbi 7 Ar Ac + B + 5 (Pi) / 2 Pl (L1) + Am (-L 2) D Qc Ar + K, (Amn) (L 3) ( K-1) (Amn) (L 2) - (T / C) (L 2,) p R = C (1 + Doc 2) 1 / -2 p = Ar arctg (Doc) X ((r Ocos (p ) + l (Tl) ein (Ar-) lTT) IL 4 y = (R) sin (p) 1 (Tl) cos (Ar) lTT, 8 Ac Ac + Ai 9 Si Ar 2 (pi) (Nw) + Pi / 2, go to step 2

The process is finished.

NOMENCLATURE

  E = Eccentricity C (PI) T C = Radius of the generating circle, L = Distance between the geometric center of the spiral in orbit and the center P of the Vaxe de bielletteo

Ac = Angle of "correspondence".

  Kl = Value of the modification added to the outside edge of the fixed spiral divided by the total change between the fixed and moving inner sidewalls, K 2 = Value of the modification added to the inner side of the fixed spiral divided by the total change between the flanks fixed interior and mobile exterior

R = Amplitude of the polar vector.

Ar = Rolling angle.

  Aro = Rolling angle (Ar) of the moving spiral (in gold, dick).

  Arf = Rolling angle (Ar) of the fixed spiral.

  B = Angle between the start of the involute of the base circle in orbit and the center of the pivot axis (polar). T = Thickness of spiral winding, Ai Increment angle (c 9 is the angle at which

AC is incremented).

  Au = truncated cone angle in Figure 20 B (angle between the x-axis and a line perpendicular to a line tangent to the base generator circle and passing through

  tangency of the inner physical end of an

  rolling and involute curves from-

  which flanks are produced} Q Tl = Tool radius, D = Distance between center of base circle and center of

the anchor axis.

  Lik = Length of the rotation control panel (4 bar)

LOGIC COEFFICIENTS:

  Surface L 1 L 2 L 3 L 4 TT Fixed int 1 O 1 -1 -1 Fixed ext OO 1 -1 1 Mobile int 1 1 O 1 -1 Ext mobile O 1 O 1 1 The present invention comprises a very simple method and unique manufacturing of fixed windings and in orbit on a numerically controlled machine or ma,

  China similarly using the shift technique

  The process is shown diagrammatically in FIG. 24, where the reference 300 represents a part to be given the shape of a spiral, 302 a support assembly of the part 300 during its machining by a milling cutter 304, which The machine which positions the mill 304 with respect to the workpiece 300 is programmed in the usual manner so as to form the profiles of the inner and outer flanks (identical curves) from the common base generator circle of the machine. spiral So, if the piece is fixed in a

  position on the whole during the entire operation of

  flanks, a conventional winding of uniform thickness

  shape can be obtained both sides being devel-

from the same base circle,

  However, in the practice of this

  the outer flank of the winding is machined when

  that the piece is in the position shown, where it is

  placed against a stop 308, and the inner flank of the

  The bearing is machined when the piece is placed against a

  stop 306, no other changes being made to loriten-

  the distance between stops 306 and 308 is

  equal to the total value of the displacement of the general circle

  According to the criteria disclosed in connection with the shifting method described above, plus the overall dimension of the workpiece between the stops, this is a 4d. That the distance of the displacement between the stop 308 and the abutment 306 is equal to the desired displacement of the basic generating circles, the distribution of the value of the correction applied to each flank is in turn determined by the base position Cpoint of reference) of

  the cutting tool 304 relative to the stops 306 and 308.

  If the base position is centered, the same correction

  can be applied to each sidewall.

  The present invention is not limited to the embodiments which have just been described.

  is, on the contrary, susceptible of modifications and

  which will appear to those skilled in the art, 38,

Claims (32)

  Spiral type machine comprising a first spiral element having a first spiral winding; and a second spiral element having a second spiral winding and being mounted for movement relative to the first spiral element, the second winding being meshing with the first winding so that when the second winding moves   compared to the first following a prede-   finished, pockets of fluid having a gradually changing volume are formed; characterized in that it comprises means for bringing the   second winding to move along the predetermined path   completed, comprising: driving means for bringing a first point of the second spiral element to   to move along a general orbital route-   circularly with respect to the first spiral element, and rotation control means for   limit the rotational movement of the second element   spiral by restricting the movement of a second point of   Machine according to claim 1, wherein the   placement of the second point is limited to a sensitive path-   rectilinear with respect to the first spiral element, 3 Machine according to claim 2, characterized in that the rectilinear path generally extends   radially with respect to the second spiral winding.   Machine according to claim 2, characterized   in that the rectilinear path is slightly shaped arc.   39. Mach Dne according to xerevendication 2, characteris-   in that the rectilinear path is a real li- right,   Machine according to any of the claims   1 to 5, characterized in that the first point is disposed at the center of the second spiral winding,   Machine according to any one of the   1 to 6, characterized in that the second point is arranged radially outside the second winding spiral.   Machine according to any of the claims   cations 1 to 7, characterized in that each of the coils   e Dspirale has an inner and outer flank having a   thread that is the involutive of a circle,   Machine according to any one of the   cations 1 & 7, characterized in that each of the   Spiral elements have an inner and outer flank   having a profile that is the developing of a geometric form flat stick.   Machine according to claim 9, characterized   in that the center of the generating form of the involute profile of the outer flank of the two windings is displaced with respect to the center of the generating form   of the involute profile of the inner flank of the same rolling.   Machine according to claim 9, characterized   in that the center of the form generating the profile   involute of the outside flank of one of the   ments is moved in relation to the center of the generic form.   of the involute profile of the inner flank of the same winding.   Machine according to claim 11, characterized   in that the rotation control means is connected   to the second spiral element at substantially a single point   that and that the centers are moved one relative to 4 Q,   the other along a line substantially equal to one   extending between the single point and the center of the   cond winding when the spiral elements do not turn   1 Machine according to claim 12, characterized in that the geometrical shapes are circles having the same radius, these centers being displaced one by one.   to each other on each winding according to a quantity   equal to EC / L, o E = radius of gold Dbte F C = radius of the base generator circle; The distance between the geometric center of the second winding and the second point   Machine according to any of the claims   1 to 13, characterized in that the rotation control means comprises a rod having a portion pivotally connected to the second spiral member and another portion rotatably mounted about an axis which is fixed relative to the first member member. spiral,   Machine according to claim 14; character-   in that the axis of the link extending between the link portions is generally perpendicular to a   radius of the second winding through the pivotal connection   aunt between the link and the second spiral element.   Machine according to claims 14 or 15,   characterized in that the pivotal connection between the biel-   lette and the second spiral element is arranged radially   outwardly from the second winding,   Machine according to claims 14, 15 or   16, characterized in that the other part of the link   is mounted on the first spiral element.   Machine according to claims 14, 15 or   16, characterized in that it is arranged inside a hermetic envelope, and in that the other part of 41, the connecting rod is mounted on this envelope,   19 Machine according to any one of the   1 to 18, characterized in that the means for com-   rotation includes a four bar linkage interconnecting the movable spiral element and a structure fixed support.   Machine according to any one of the   1 to 19, characterized in that the means for   rotation mechanism comprises a crank and slide mechanism interconnecting the movable spiral element and a fixed support structure.   Machine according to any one of the   1 to 20, characterized in that it comprises in   in addition to a crankshaft rotated around a first   first axle, this crankshaft having a driving surface   generally flat which is situated in a plane perpendicular   to a first axis radius and spaced from this axis, a drive member having a generally flat driven surface in driving engagement with the driving surface, and driven means of the second spiral member pivotally connected to the first axis; 'element   for rotation with respect thereto,   turn of a second axis spaced from the first axis, from which it results   that the rotation of the crankshaft causes the second axis of the second spiral element to orbit relative to the first spiral element about the first axis.   Machine according to claim 21, characterized   in that the plane of the driving surface is substantially parallel to a plane passing through the first and second axes.   Gelon machine according to claims 21 or 22,   characterized in that the drive element is free to slide on the drive surface in the case where a   obstacle temporarily prevents the second element 42,   to follow his normal course of travel.   Machine according to claims 21, 22,   or 23, characterized in that the drive element   has a generally annular sectional shape.   Machine according to claims 21, 22,   23 or 24, characterized in that the driving element is generally cylindrical, and the driven surface is disposed on its outer periphery,   Machine according to claims 1 to 25,   characterized in that: the first spiral element has a first flat sealing surface and the spiral winding has a first flat end surface;   the second spiral element has a se-   flat sealing surface and the second winding   spirally presents a second extreme surface   you; the second spiral element being mounted to move relative to the first spiral element,   the second winding being   born with the first winding so that,   when the second winding moves   port to the first winding along a predetermined path, the inner and outer flanks   of a significant part of each of the   are in contact to form fluid pockets having a progressively changing volume, the first end surface sealingly engaging the second sealing surface and the second end surface   coming into sealed contact with the first sur-   sealing face to seal the pockets, each of the windings being dis-   laid so that the outside flank of its   extreme external terminal does not come 43,   in contact with the flank of the other winding   this extreme end part, each winding being substantially thicker   in the radial direction that the rest of that-   in order to support a disproportionate   tionally large axial loads acting on the spiral elements.   Machine according to claim 26,   characterized in that it further comprises a feed groove   oil in one of the end surfaces, and a means for supplying oil to said groove for the purpose of reducing friction. The machine of claim 26 or 27, characterized in that it further comprises means for supplying lubricating oil to at least one of the sealing surfaces in an area where it is   in contact with an extreme surface.   Machine according to claims 26, 27 or   28, characterized in that at least one of the ex-parties   terminal tres extends about 180.   Machine according to any one of the   cations 1 to 29, characterized in that it further comprises a fixed support structure for supporting the first spiral member; a thrust bearing disposed between the fixed support structure and the second spiral element,   this level being generally canceled   plan and having an uninterrupted, flat, parallel bearing surface on its face facing the fixed support structure, and a lubricating means for providing   the oil at the interface between the thrust bearing and the   fixed support to create a film between them   the oil, 44, the tiny shake resulting from the   second spiral element during its movement   in orbit relative to the first spiral element causing a compression film phenomenon between the thrust bearing and the fixed support structure,   Machine according to claim 30, characterized   in that the thrust bearing is attached to the second spiral element.   Machine according to any of the claims   cations 1 to 31, characterized in that it further comprises: a crankshaft rotated about a first axis, said crankshaft having a cylindrical driving surface, the axis of curvature of which is parallel to the first axis;   a training element with an over-   cylindrical driven face in motor engagement with the driving surface; and driven means on the second spiral member pivotally connected to the drive member for rotation relative thereto about a third axis spaced from the first axis parallel thereto, with the result that the rotation of the crankshaft causes the movement in orbit of the third axis of the second spiral element relative to the first spiral element to turn of the first axis.   Machine according to claim 32, characterized   in that the axis of curvature of the drive surface is spaced from the first axis,   Machine according to claims 32 or 33,   characterized in that the axis of curvature of the driving surface is spaced from the third axis,   M machine according to claims 32, 33 or   34, characterized in that the entrained and driven surfaces have a common axis of curvature,   Machine according to claims 32, 33,   34 or 35, characterized in that the first axis is spaced   of the axis of curvature greater than the spacing of the third axis.   Machine according to claims 32, 33,   34, 35 or 36, characterized in that the axis of curvature   is spaced from the plane of the first and third axes.   38 -Machine according to claims 32, 33,   34, 35, 36 or 37, characterized in that the element   dragging can rotate freely in relation to the crankshaft   around the axis of curvature in the event of an obstacle   temporarily prevents the second spiral element from following its normal movement course,   Machine according to claims 32-37 or   38, characterized in that the driving element has a   section in generally annular section.   Machine according to any one of the   cations 1 to 39, characterized in that; the profiles of the inner and outer flanks of the first winding are each the involute of the same geometrical planar generating shape, the center of the generative shape of the profile of the outer flank of the first winding being displaced with respect to the center of the generating shape of the flank profile inside the first winding,