PATENT ABSTRACT
The present invention provides the art with a scroll machine which has a plurality of built-in volume ratios along with their respective design pressure ratios. The incorporation of more than one built-in volume ratio allows a single compressor to be optimized for more than one operating condition. The operating envelope for the compressor will determine which of the various built-in volume ratios is going to be selected. Each volume ratio includes a discharge passage extending between one of the pockets of the scroll machine and the discharge chamber. All but the highest volume ration utilize a valve controlling the flow through the discharge passage.

PATENT DESCRIPTION
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]    This application is a continuation-in-part application of U.S. patent application Ser. No. 09/688,549 filed on Oct. 16, 2000. The disclosure of the above application is incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention relates to generally to scroll machines. More particularly, the present invention relates to a dual volume ratio scroll machine, having a multi-function seal system which utilizes flip or flip seals.  
         BACKGROUND AND SUMMARY OF THE INVENTION  
         [0003]    A class of machines exists in the art generally known as scroll machines which are used for the displacement of various types of fluids. Those scroll machines can be configured as an expander, a displacement engine, a pump, a compressor, etc., and the features of the present invention are applicable to any one of these machines. For purposes of illustration, however, the disclosed embodiments are in the form of a hermetic refrigerant compressor.  
           [0004]    Scroll-type apparatus have been recognized as having distinct advantages. For example, scroll machines have high isentropic and volumetric efficiency, and hence are small and lightweight for a given capacity. They are quieter and more vibration free than many compressors because they do not use large reciprocating parts (e.g. pistons, connecting rods, etc.). All fluid flow is in one direction with simultaneous compression in plural opposed pockets which results in less pressure-created vibrations. Such machines also tend to have high reliability and durability because of the relatively few moving parts utilized, the relatively low velocity of movement between the scrolls, and an inherent forgiveness to fluid contamination.  
           [0005]    Generally speaking, a scroll apparatus comprises two spiral wraps of similar configuration, each mounted on a separate end plate to define a scroll member. The two scroll members are interfitted together with one of the scroll wraps being rotationally displaced 180 degrees from the other. The apparatus operates by orbiting one scroll member (the orbiting scroll member) with respect to the other scroll member (the non-orbiting scroll) to produce moving line contacts between the flanks of the respective wraps. These moving line contacts create defined moving isolated crescent-shaped pockets of fluid. The spiral scroll wraps are typically formed as involutes of a circle. Ideally, there is no relative rotation between the scroll members during operation, the movement is purely curvilinear translation (no rotation of any line on the body). The relative rotation between the scroll members is typically prohibited by the use of an Oldham coupling.  
           [0006]    The moving fluid pockets carry the fluid to be handled from a first zone in the scroll machine where a fluid inlet is provided, to a second zone in the scroll machine where a fluid outlet is provided. The volume of the sealed pocket changes as it moves from the first zone to the second zone. At any one instant of time, there will be at least one pair of sealed pockets, and when there are several pairs of sealed pockets at one time, each pair will have different volumes. In a compressor, the second zone is at a higher pressure than the first zone and it is physically located centrally within the machine, the first zone being located at the outer periphery of the machine.  
           [0007]    Two types of contacts define the fluid pockets formed between the scroll members. First, there is axially extending tangential line contacts between the spiral faces or flanks of the wraps caused by radial forces (“flank sealing”). Second, there are area contacts caused by axial forces between the plane edge surfaces (the “tips”) of each wrap and the opposite end plate (“tip sealing”). For high efficiency, good sealing must be achieved for both types of contacts, however, the present invention is concerned with tip sealing.  
           [0008]    To maximize efficiency, it is important for the wrap tips of each scroll member to sealingly engage the end plate of the other scroll so that there is minimum leakage therebetween. One way this has been accomplished, other than using tip seals (which are very difficult to assembly and which often present reliability problems) is by using fluid under pressure to axially bias one of the scroll members against the other scroll member. This of course, requires seals in order to isolate the biasing fluid at the desired pressure. Accordingly, there is a continuing need in the field of scroll machines for axial biasing techniques including improved seals to facilitate the axial biasing.  
           [0009]    One aspect of the present invention provides the art with several unique sealing systems for the axial biasing chamber of a scroll-type apparatus. The seals of the present invention are embodied in a scroll compressor and suited for use in machines which use discharge pressure alone, discharge pressure and an independent intermediate pressure, or solely an intermediate pressure, in order to provide the necessary axial biasing forces to enhance tip sealing. In addition, the seals of the present invention are suitable particularly for use in applications which bias the non-orbiting scroll member towards the orbiting scroll member.  
           [0010]    A typical scroll machine which is used as a scroll compressor for an air conditioning application is a single volume ratio device. The volume ratio of the scroll compressor is the ratio of the gas volume trapped at suction closing to the gas volume at the onset of discharge opening. The volume ratio of the typical scroll compressor is “built-in” since it is fixed by the size of the initial suction pocket and the length of the active scroll wrap. The built-in volume ratio and the type of refrigerant being compressed determine the single design pressure ratio for the scroll compressor where compression lossed due to pressure ratio mismatch is avoided. The design pressure ratio is generally chosen to closely match the primary compressor rating point, however, it may be biased towards a secondary rating point.  
           [0011]    Scroll compressor design specifications for air conditioning applications typically include a requirement that the motor which drives the scroll members must be able to withstand a reduced supply voltage without overheating. While operating at this reduced supply voltage, the compressor must operate at a high-load operating condition. When the motor is sized to meet the reduced supply voltage requirement, the design changes to the motor will generally conflict with the desire to maximize the motor efficiency at the primary compressor rating point. Typically, the increasing of motor output torque will improve the low voltage operation of the motor but this will also reduce the compressor efficiency at the primary rating point. Conversely, any reduction that can be made in the design motor torque while still being able to pass the low-voltage specification allows the selection of a motor which will operate at a higher efficiency at the compressor primary rating point.  
           [0012]    Another aspect of the present invention improves the operating efficiency of the scroll compressor through the existence of a plurality of built-in volume ratios and their corresponding design pressure ratios. For exemplary purposes, the present invention is described in a compressor having two built-in volume ratios and two corresponding design pressure ratios. It is to be understood that additional built-in volume ratios and corresponding design pressure ratios could be incorporated into the compressor if desired.  
           [0013]    Other advantages and objects of the present invention will become apparent to those skilled in the art from the subsequent detailed description, appended claims and drawings.  
           [0014]    Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]    The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein:  
         [0016]    [0016]FIG. 1 is a vertical sectional view of a scroll type refrigerant compressor incorporating the sealing system and the dual volume ratio in accordance with the present invention;  
         [0017]    [0017]FIG. 2 is a cross-sectional view of the refrigerant compressor shown in FIG. 1, the section being taken along line  2 - 2  thereof;  
         [0018]    [0018]FIG. 3 is a partial vertical sectional view of the scroll type refrigerant compressor shown in FIG. 1 illustrating the pressure relief systems incorporated into the compressor;  
         [0019]    [0019]FIG. 4 is a cross-sectional view of the refrigerant compressor shown in FIG. 1, the section being taken along line  2 - 2  thereof with the partition removed;  
         [0020]    [0020]FIG. 5 is a typical compressor operating envelope for an air-conditioning application with the two design pressure ratios being identified;  
         [0021]    [0021]FIG. 6 is an enlarged view of a portion of a compressor in accordance With another embodiment of the present invention;  
         [0022]    [0022]FIG. 7 is an enlarged view of a portion of a compressor in accordance with another embodiment of the present invention;  
         [0023]    [0023]FIG. 8 is an enlarged view of a portion of a compressor in accordance with another embodiment of the present invention;  
         [0024]    [0024]FIG. 9 is an enlarged view of a portion of a compressor in accordance with another embodiment of the present invention;  
         [0025]    [0025]FIG. 10 is an enlarged view of a portion of a compressor in accordance with another embodiment of the present invention;  
         [0026]    [0026]FIG. 11 is an enlarged plan view of a portion of the sealing system according to the present invention shown in FIG. 3;  
         [0027]    [0027]FIG. 12 is an enlarged vertical sectional view of circle  12  shown in FIG. 11;  
         [0028]    [0028]FIG. 13 is a cross-sectional view of a seal groove in accordance with another embodiment of the present invention;  
         [0029]    [0029]FIG. 14 is a cross-sectional view of a seal groove in accordance with another embodiment of the present invention;  
         [0030]    [0030]FIG. 15 is a partial vertical sectional view of a scroll type refrigerant compressor incorporating a sealing system in accordance with another embodiment of the present invention;  
         [0031]    [0031]FIG. 16 is a partial vertical sectional view of a scroll type refrigerant compressor incorporating a sealing system in accordance with another embodiment of the present invention;  
         [0032]    [0032]FIG. 17 is a partial vertical sectional view of a scroll type refrigerant compressor incorporating a sealing system in accordance with another embodiment of the present invention;  
         [0033]    [0033]FIG. 18 is a partial vertical sectional view of a scroll type refrigerant compressor incorporating a sealing system in accordance with another embodiment of the present invention;  
         [0034]    [0034]FIG. 19 is a partial vertical sectional view similar to FIG. 18 but also incorporating a capacity modulation system;  
         [0035]    [0035]FIG. 20 is a partial vertical sectional view of a scroll type refrigerant compressor incorporating a sealing system in accordance with another embodiment of the present invention;  
         [0036]    [0036]FIG. 21 is a partial vertical sectional view of a scroll type refrigerant compressor incorporating a sealing system in accordance with another embodiment of the present invention;  
         [0037]    [0037]FIG. 22 is a partial vertical sectional view similar to FIG. 21 but also incorporating a capacity modulation system;  
         [0038]    FIGS.  23 A- 23 H are enlarged sectional views illustrating various seal groove geometries in accordance with the present invention;  
         [0039]    [0039]FIG. 24 is a cross-sectional view of an as-molded flat top seal; and  
         [0040]    [0040]FIG. 25 is a cross-sectional view of a flip seal in it L-shaped operational condition.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0041]    Although the principles of the present invention may be applied to many different types of scroll machines, they are described herein, for exemplary purposes, embodied in a hermetic scroll compressor, and particularly one which has been found to have specific utility in the compression of refrigerant for air conditioning and refrigeration systems.  
         [0042]    The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. Referring now to the drawings in which like reference numerals designate like or corresponding parts throughout the several views, there is shown in FIGS. 1 and 2 a scroll compressor incorporating a unique dual volume-ratio system in accordance with the present invention and which is designated generally by the reference numeral  10 . Scroll compressor  10  comprises a generally cylindrical hermetic shell  12  having welded at the upper end thereof a cap  14  and at the lower end thereof a base  16  having a plurality of mounting feet (not shown) integrally formed therewith. Cap  14  is provided with a refrigerant discharge fitting  18  which may have the usual discharge valve therein (not shown). Other major elements affixed to the shell include a transversely extending partition  22  which is welded about its periphery at the same point that cap  14  is welded to shell  12 , a main bearing housing  24  which is suitably secured to shell  12  and a lower bearing housing  26  having a plurality of radially outwardly extending legs each of which is also suitably secured to shell  12 . A motor stator  28  which is generally square in cross-section but with the corners rounded off is press fitted into shell  12 . The flats between the rounded corners on the stator provide passageways between the stator and shell, which facilitate the return flow of lubricant from the top of the shell to the bottom.  
         [0043]    A drive shaft or crankshaft  30  having an eccentric crank pin  32  at the upper end thereof is rotatably journaled in a bearing  34  in main bearing housing  24  and a second bearing  36  in lower bearing housing  26 . Crankshaft  30  has at the lower end a relatively large diameter concentric bore  38  which communicates with a radially outwardly inclined smaller diameter bore  40  extending upwardly therefrom to the top of crankshaft  30 . Disposed within bore  38  is a stirrer  42 . The lower portion of the interior shell  12  defines an oil sump  44  which is filled with lubricating oil to a level slightly above the lower end of a rotor  46 , and bore  38  acts as a pump to pump lubricating fluid up the crankshaft  30  and into passageway  40  and ultimately to all of the various portions of the compressor which require lubrication.  
         [0044]    Crankshaft  30  is rotatively driven by an electric motor including stator  28 , windings  48  passing therethrough and rotor  46  press fitted on crankshaft  30  and having upper and lower counterweights  50  and  52 , respectively.  
         [0045]    The upper surface of main bearing housing  24  is provided with an annular flat thrust bearing surface  54  on which is disposed an orbiting scroll member  56  having the usual spiral vane or wrap  58  extending upward from an end plate  60 . Projecting downwardly from the lower surface of end plate  60  of orbiting scroll member  56  is a cylindrical hub having a journal bearing  62  therein and in which is rotatively disposed a drive bushing  64  having an inner bore  66  in which crank pin  32  is drivingly disposed. Crank pin  32  has a flat on one surface which drivingly engages a flat surface (not shown) formed in a portion of bore  66  to provide a radially compliant driving arrangement, such as shown in assignee&#39;s U.S. Pat. No. 4,877,382, the disclosure of which is hereby incorporated herein by reference. An Oldham coupling  68  is also provided positioned between orbiting scroll member  56  and bearing housing  24  and keyed to orbiting scroll member  56  and a non-orbiting scroll member  70  to prevent rotational movement of orbiting scroll member  56 .  
         [0046]    Non-orbiting scroll member  70  is also provided having a wrap  72  extending downwardly from an end plate  74  which is positioned in meshing engagement with wrap  58  of orbiting scroll member  56 . Non-orbiting scroll member  70  has a centrally disposed discharge passage  76  which communicates with an upwardly open recess  78  which in turn is in fluid communication with a discharge muffler chamber  80  defined by cap  14  and partition  22 . A first and a second annular recess  82  and  84  are also formed in non-orbiting scroll member  70 . Recesses  82  and  84  define axial pressure biasing chambers which receive pressurized fluid being compressed by wraps  58  and  72  so as to exert an axial biasing force on non-orbiting scroll member  70  to thereby urge the tips of respective wraps  58 ,  72  into sealing engagement with the opposed end plate surfaces of end plates  74  and  60 , respectively. Outermost recess  82  receives pressurized fluid through a passage  86  and innermost recess  84  receives pressurized fluid through a plurality of passages  88 . Disposed between non-orbiting scroll member  70  and partition  22  are three annular pressure actuated flip seals  90 ,  92  and  94 . Seals  90  and  92  isolate outermost recess  82  from a suction chamber  96  and innermost recess  84  while seals  92  and  94  isolate innermost recess  84  from outermost recess  82  and discharge chamber  80 .  
         [0047]    Muffler plate  22  includes a centrally located discharge port  100  which receives compressed refrigerant from recess  78  in non-orbiting scroll member  70 . When compressor  10  is operating at its full capacity or at its highest design pressure ratio, port  100  discharges compressed refrigerant to discharge chamber  80 . Muffler plate  22  also includes a plurality of discharge passages  102  located radially outward from discharge port  100 . Passages  102  are circumferentially spaced at a radial distance where they are located above innermost recess  84 . When compressor  10  is operating at its reduced capacity or at its lower design pressure ratio, passages  102  discharge compressed refrigerant to discharge chamber  80 . The flow of refrigerant through passages  102  is controlled by a valve  104  mounted on partition  22 . A valve stop  106  positions and maintains valve  104  on muffler plate  22  such that it covers and closes passages  102 .  
         [0048]    Referring now to FIGS. 3 and 4, a temperature protection system  110  and a pressure relief system  112  are illustrated. Temperature protection system  110  comprises an axially extending passage  114 , a radially extending passage  116 , a bimetallic disc  118  and a retainer  120 . Axial passage  114  intersects with radial passage  116  to connect recess  84  with suction chamber  96 . Bi-metallic disc  118  is located within a circular bore  122  and it includes a centrally located indentation  124  which engages axial passage  114  to close passage  114 . Bi-metallic disc  118  is held in position within bore  122  by retainer  120 . When the temperature of refrigerant in recess  84  exceeds a predetermined temperature, bi-metallic disc  118  will snap open or move into a domed shape to space indentation  124  from passage  114 . Refrigerant will then flow from recess  84  through a plurality of holes  126  in disc  118  into passage  114  into passage  116  and into suction chamber  96 . The pressurized gas within recess  82  will vent to recess  84  due to the loss of sealing for annular seal  92 .  
         [0049]    When the pressurized gas within recess  84  is vented, annular seal  92  will lose sealing because it, like seals  90  and  94 , are energized in part by the pressure differential between adjacent recesses  82  and  84 . The loss of pressurized fluid in recess  84  will thus cause fluid to leak between recess  82  and recess  84 . This will result in the removal of the axial biasing force provided by pressurized fluid within recesses  82  and  84  which will in turn allow separation of the scroll wrap tips with the opposing end plate resulting in a leakage path between discharge chamber  80  and suction chamber  96 . This leakage path will tend to prevent the build up of excessive temperatures within compressor  10 .  
         [0050]    Pressure relief system  112  comprises an axially extending passage  128 , a radially extending passage  130  and a pressure relief valve assembly  132 . Axial passage  128  intersects with radial passage  130  to connect recess  84  with suction chamber  96 . Pressure relief valve assembly  132  is located within a circular bore  134  located at the outer end of passage  130 . Pressure relief valve assembly  132  is well known in the art and will therefore not be described in detail. When the pressure of refrigerant within recess  84  exceeds a predetermined pressure, pressure relief valve assembly  132  will open to allow fluid flow between recess  84  and suction chamber  96 . The venting of fluid pressure by valve assembly  132  will affect compressor  10  in the same manner described above for temperature protection system  110 . The leakage path which is created by valve assembly  132  will tend to prevent the build-up of excessive pressures within compressor  10 . The response of valve assembly  132  to excessive discharge pressures is improved if the compressed pocket that is in communication with recess  84  is exposed to discharge pressure for a portion of the crank cycle. This is the case if the length of the active scroll wraps  58  and  72  needed to compress between an upper design pressure ratio  140  and a lower design pressure  142  (FIG. 5) is less then 360°.  
         [0051]    Referring now to FIG. 5, a typical compressor operating envelope for an air conditioning application is illustrated. Also shown are the relative locations for upper design pressure ratio  140  and lower design pressure ratio  142 . Upper design pressure ratio  140  is chosen to optimize operation of compressor  10  at the motor low-voltage test point. When compressor  10  is operating at this point, the refrigerant being compressed by scroll members  56  and  70  enter discharge chamber  80  through discharge passage  76 , recess  78  and discharge port  100 . Discharge passages  102  are closed by valve  104  which is urged against partition  22  by the fluid pressure within discharge chamber  80 . Increasing the overall efficiency of compressor  10  at design pressure ratio  140  allows the design motor torque to be reduced which yields increased motor efficiency at the rating point. Lower design pressure ratio  142  is chosen to match the rating point for compressor  10  to further improve efficiency.  
         [0052]    Thus, if the operating point for compressor  10  is above lower design pressure ratio  142 , the gas within the scroll pockets is compressed along the full length of wraps  58  and  72  in the normal manner to be discharged through passage  76 , recess  78  and port  100 . If the operating point for compressor  10  is at or below lower design pressure ratio  142 , the gas within the scroll pockets is able to discharge through passages  102  by opening valve  104  before reaching the inner ends of scroll wraps  58  and  72 . This early discharging of the gas avoids losses due to compression ratio mismatch.  
         [0053]    Outermost recess  82  acts in a typical manner to offset a portion of the gas separating forces in the scroll compression pockets. The fluid pressure within recess  82  axially bias the vane tips of non-orbiting scroll member  70  into contact with end plate  60  of orbiting scroll member  56  and the vane tips of orbiting scroll member  56  into contact with end plate  74  of non-orbiting scroll member  70 . Innermost recess  84  acts in this typical manner at a reduced pressure when the operating condition of compressor  10  is below lower design pressure ratio  142  and at an increased pressure when the operating condition of compressor  10  is at or above lower design pressure ratio  142 . In this mode, recess  84  can be used to improve the axial pressure balancing scheme since it provides an additional opportunity to minimize the tip contact force.  
         [0054]    In order to minimize the re-expansion losses created by axial passages  88  and  102  used for early discharge end, the volume defined by innermost recess  84  should be held to a minimum. An alternative to this would be to incorporate a baffle plate  150  into recess  84  as shown in FIGS. 1 and 6. Baffle plate  150  controls the volume of gas that passes into recess  84  from the compression pockets. Baffle plate  150  operates similar to the way that valve plate  104  operates. Baffle plate  150  is constrained from angular motion but it is capable of axial motion within recess  84 . When baffle plate  150  is at the bottom of recess  84  in contact with non-orbiting scroll member  70 , the flow of gas into recess  84  is minimized. Only a very small bleed hole  152  connects the compression pocket with recess  84 . Bleed hole  152  is in line with one of the axial passages  88 . Thus, expansion losses are minimized. When baffle plate  150  is spaced from the bottom of recess  84 , sufficient gas flow for early discharging flows through a plurality of holes  154  offset in baffle plate  150 . Each of the plurality of holes  154  is in line with a respective passage  102  and not in line with any of passages  88 . When using baffle plate  150  and optimizing the response of pressure relief valve assembly  132  by having an active scroll length of 360° between ratios  140  and  142  as described above, the trade off for this increased response will be the possibility of the opening of baffle plate  150 .  
         [0055]    Referring now to FIG. 6, an enlarged section of recesses  78  and  84  of non-orbiting scroll member  70  is illustrated according to another embodiment of the present invention. In this embodiment, a discharge valve  160  is located within recess  78 . Discharge valve  160  includes a valve seat  162 , a valve plate  164  and a retainer  166 .  
         [0056]    Referring now to FIG. 7, an enlarged section of recesses  78  and  84  of non-orbiting scroll member  70  is illustrated according to another embodiment of the present invention. In this embodiment valve  104  and baffle plate  150  are connected by a plurality of connecting members  170 . Connecting members  170  require that valve  104  and baffle plate  150  move together. The benefit to connecting valve  104  and baffle plate  150  is to avoid any dynamic interaction between the two.  
         [0057]    Referring now to FIG. 8, an enlarged section of recesses  78  and  84  of non-orbiting scroll member  70  is illustrated according to another embodiment of the present invention. In this embodiment valve  104  and baffle plate  150  are replaced with a single unitary valve  104 ′. Using single unitary valve  104 ′ has the same advantages as those described for FIG. 7 in that dynamic interaction is avoided.  
         [0058]    Referring now to FIG. 9, an enlarged section of recesses  78  and  84  of a non-orbiting scroll member  270  is illustrated according to another embodiment of the present invention. Scroll member  270  is identical to scroll member  70  except that a pair of radial passages  302  replace the plurality of passages  102  through partition  22 . In addition, a curved flexible valve  304  located along the perimeter of recess  78  replaces valve  104 . Curved flexible valve  304  is a flexible cylinder which is designed to flex and thus to open radial passages  302  in a similar manner with the way that valve  104  opens passages  102 . The advantage to this design is that a standard partition  22  which does not include passages  102  can be utilized. While this embodiment discloses radial passage  302  and flexible valve  304 , it is within the scope of the present invention to eliminate passage  302  and valve  304  and design flip seal  94  to function as the valve between innermost recess  84  and discharge chamber  80 . Since flip  94  is a pressure actuated seal, the higher pressure within discharge chamber  80  over the pressure within recess  84  actuates flip seal  94 . Thus, if the pressure within recess  84  would exceed the pressure within discharge chamber  80 , flip seal  94  could be designed to open and allow the passage of the high pressure gas.  
         [0059]    Referring now to FIG. 10, an enlarged section of recesses  78  and  84  of a non-orbiting scroll member  370  is illustrated according to another embodiment of the present invention. Scroll member  370  is identical to scroll member  70  except that the pair of radial passages  402  replace the plurality of passages  102  through partition  22 . In addition, a valve  404  is biased against passages  402  by a retaining spring  406 . A valve guide  408  controls the movement of valves  404 . Valves  404  are designed to open radial passages  402  in a similar manner with the way that valve  104  opens passages  102 . The advantage to this design is again that a standard partition  22  which does not include passages  102  can be utilized.  
         [0060]    While not specifically illustrated, it is within the scope of the present invention to configure each of valves  404  such that they perform the function of both opening passages  402  and minimize the re-expansion losses created through passages  88  in a manner equivalent to that of baffle plate  150 .  
         [0061]    With reference to FIGS. 1, 2,  11  and  12 , flip seals  90 ,  92  and  94  are each configured during installation as an annular L-shaped seal. Outer flip seal  90  is disposed within a groove  200  located within non-orbiting scroll member  70 . One leg of flip seal  90  extends into groove  200  while the other leg extends generally horizontal, as shown in FIGS. 1, 2 and  12  to provide sealing between non-orbiting scroll member  70  and muffler plate  22 . Flip seal  90  functions to isolate recess  82  from the suction area of compressor  10 . The initial forming diameter of flip seal  90  is less than the diameter of groove  200  such that the assembly of flip seal  90  into groove  200  requires stretching of flip seal  90 . Preferably, flip seal  90  is manufactured from a Teflon® material containing 10% glass when interfacing with steel components.  
         [0062]    Center flip seal  92  is disposed within a groove  204  located within non-orbiting scroll member  70 . One leg of flip seal  92  extends into groove  204  while the other leg extends generally horizontal, as shown in FIGS. 1, 2 and  12  to provide sealing between non-orbiting scroll member  70  and muffler plate  22 . Flip seal  92  functions to isolate recess  82  from the bottom of recess  84 . The initial forming diameter of flip seal  92  is less than the diameter of groove  204  such that the assembly of flip seal  92  into groove  204  requires stretching of flip seal  92 . Preferably, flip seal  92  is manufactured from a Teflon® material containing 10% glass when interfacing with steel components.  
         [0063]    Inner flip seal  94  is disposed within a groove  208  located within non-orbiting scroll member  70 . One leg of flip seal  94  extends into groove  208  while the other leg extends generally horizontal, as shown in FIGS. 1, 2 and  12  to provide sealing between non-orbiting scroll member  70  and muffler plate  22 . Flip seal  94  functions to isolate recess  84  from the discharge area of compressor  10 . The initial forming diameter area of flip seal  94  is less than the diameter of groove  208  such that the assembly of flip seal  94  into groove  208  requires stretching of flip seal  94 . Preferably, flip seal  94  is manufactured from a Teflon® material containing 10% glass when interfacing with steel components.  
         [0064]    Seals  90 ,  92  and  94  therefore provide three distinct seals; namely, an inside diameter seal of seal  94 , an outside diameter seal of seal  90 , and a middle diameter seal of seal  92 . The sealing between muffler plate  22  and seal  94  isolates fluid under intermediate pressure in recess  84  from fluid under discharge pressure. The sealing between muffler plate  22  and seal  90  isolates fluid under intermediate pressure in recess  82  from fluid under suction pressure. The sealing between muffler plate  22  and seal  92  isolates fluid under intermediate pressure in recess  84  from fluid under a different intermediate pressure in recess  82 . Seals  90 ,  92  and  94  are pressure activated seals as described below.  
         [0065]    Grooves  200 ,  204  and  208  are all similar in shape. Groove  200  will be described below. It is to be understood that grooves  204  and  208  include the same features as groove  200 . Groove  200  includes a generally vertical outer wall  240 , a generally vertical inner wall  242  and an undercut portion  244 . The distance between walls  240  and  242 , the width of groove  200 , is designed to be slightly larger than the width of seal  90 . The purpose for this is to allow pressurized fluid from recess  82  into the area between seal  90  and wall  242 . The pressurized fluid within this area will react against seal  90  forcing it against wall  240  thus enhancing the sealing characteristics between wall  240  and seal  90 . Undercut  244  is positioned to lie underneath the generally horizontal portion of seal  90  as shown in FIG. 12. The purpose for undercut  244  is to allow pressurized fluid within recess  82  to act against the horizontal portion of seal  92  urging it against muffler plate  22  to enhance its sealing characteristics. Thus, the pressurized fluid within recess  82  reacts against the inner surface of seal  90  to pressure activate seal  90 . As stated above, grooves  204  and  208  are the same as groove  200  and therefore provide the same pressure activation for seals  92  and  94 . FIGS.  23 A- 23 H illustrate additional configurations for grooves  200 ,  204  and  208 .  
         [0066]    The unique installed L-shaped configuration of seals  90 ,  92  and  94  of the present invention are relatively simple in construction, easy to install and inspect, and effectively provide the complex sealing functions desired. The unique sealing system of the present invention comprises three flip seals  90 ,  92  and  94  that are “stretched” into place and then pressure activated. The unique seal assembly of the present invention reduces overall manufacturing costs for the compressor, reduces the number of components for the seal assembly, improves durability by minimizing seal wear and provides room to increase the discharge muffler volume for improved damping of discharging pulse without increasing the overall size of the compressor.  
         [0067]    The seals of the present invention also provide a degree of relief during flooded starts. Seals  90 ,  92  and  94  are designed to seal in only one direction. These seals can then be used to relieve high pressure fluid from the intermediate chambers or recesses  82  and  84  to the discharge chamber during flooded starts, thus reducing inter-scroll pressures and the resultant stress and noise.  
         [0068]    Referring now to FIG. 13, a groove  300  in accordance with another embodiment of the present invention is illustrated. Groove  300  includes an outwardly angled outer wall  340 , generally vertical inner wall  242  and undercut portion  244 . Thus, groove  300  is the same as groove  200  except that the outwardly angled outer wall  340  replaces generally vertical outer wall  240 . The function, operation and advantages of groove  300  and seal  90  are the same as groove  200  and seal  90  detailed above. The angling of the outer wall enhances the ability of the pressurized fluid within recess  82  to react against the inner surface of seal  90  to pressure activate seal  90 . It is to be understood that grooves  200 ,  204  and  208  can each be configured the same as groove  300 .  
         [0069]    Referring now to FIG. 14, a seal groove  400  in accordance with another embodiment of the present invention is illustrated. Groove  400  includes outwardly angled outer wall  340  and a generally vertical inner wall  442 . Thus, groove  400  is the same as groove  300  except that undercut portion  244  has been removed. The function, operation and advantages of groove  300  and seal  90  are the same as grooves  200  and  300  and seal  90  as detailed above. The elimination of undercut portion  244  is made possible by the incorporation of a wave spring  450  underneath seal  90 . Wave spring  450  biases the horizontal portion of seal  90  upward toward muffler plate  22  to provide a passage for the pressurized gas within recess  82  to react against the inner surface of seal  90  to pressure activate seal  90 . It is to be understood that grooves  200 ,  204  and  208  can each be configured the same as groove  400 .  
         [0070]    Referring now to FIG. 15, a sealing system  420  in accordance with another embodiment of the present invention is illustrated. Sealing system  420  seals fluid pressure between a partition  422  and a non-orbiting scroll member  470 . Non-orbiting scroll member  470  is designed to replace non-orbiting scroll member  70  or any other of the non-orbiting scroll members described. In a similar manner, partition  422  is designed to replace partition  22  in the above-described compressors.  
         [0071]    Non-orbiting scroll member  470  includes scroll wrap  72  and it defines an annular recess  484 , an outer seal groove  486  and an inner seal groove  488 . Annular recess  484  is located between outer seal groove  486  and inner seal groove  488  and it is provided compressed fluid through fluid passage  88  which opens to a fluid pocket defined by non-orbiting scroll wrap  72  of non-orbiting scroll member  470  and orbiting scroll wrap  58  of orbiting scroll member  56 . The pressurized fluid provided through fluid passage  88  is at a pressure which is intermediate or in between the suction pressure and the discharge pressure of the compressor. The fluid pressure within annular recess  484  biases non-orbiting scroll member  470  towards orbiting scroll member  56  to enhance the tip sealing characteristics between the two scroll members.  
         [0072]    A flip seal  490  is disposed within outer seal groove  486  and a flip seal  492  is disposed within inner seal groove  488 . Flip seal  490  sealingly engages non-orbiting scroll member  470  and partition  422  to isolate annular recess  484  from suction pressure. Flip seal  492  sealing engages non-orbiting scroll member  470  and partition  422  to isolate annular recess  484  from discharge pressure. While not illustrated in FIG. 15, non-orbiting scroll member  470  can include temperature protection system  110 . Also, while not illustrated, non-orbiting scroll member  470  can also include pressure relief system  112  if desired.  
         [0073]    Referring now to FIG. 16, a sealing system  520  in accordance with another embodiment of the present invention is illustrated. Sealing system  520  seals fluid pressure between a partition  522  and a non-orbiting scroll member  570 . Non-orbiting scroll member  570  is designed to replace non-orbiting scroll member  70  or any other of the non-orbiting scroll members described. In a similar manner, partition  522  is designed to replace partition  22  or any of the other of the previously described partitions.  
         [0074]    Non-orbiting scroll member  570  includes scroll wrap  72  and it defines an annular recess  584 , an outer seal groove  586  and an inner seal groove  588 . Annular recess  584  is located between outer seal groove  586  and inner seal groove  588  and it is provided with compressed fluid through fluid passage  88  which opens to a fluid pocket defined by non-orbiting scroll wrap  72  of non-orbiting scroll member  570  and orbiting scroll wrap  58  of orbiting scroll member  56 . The pressurized fluid provided through fluid passage  88  is at a pressure which is intermediate or in between the suction pressure and the discharge pressure of the compressor. The fluid pressure within annular recess  586  biases non-orbiting scroll member  570  towards orbiting scroll member  56  to enhance the tip scaling characteristics between the two scroll members.  
         [0075]    A flip seal  590  is disposed within outer seal groove  586  and a flip seal  592  is disposed within inner seal groove  588 . Flip seal  590  sealingly engages non-orbiting scroll member  570  and partition  522  to isolate annular recess  584  from suction pressure. Flip seal  592  sealingly engages non-orbiting scroll member  570  and partition  522  to isolate annular recess  584  from discharge pressure. While not specifically illustrated in FIG. 16, non-orbiting scroll member  570  can include temperature protection system  110 . Also, while not illustrated, non-orbiting scroll member  570  can also include pressure relief system  112  if desired.  
         [0076]    Referring now to FIG. 17, a sealing system  620  in accordance with another embodiment of the present invention is illustrated. Sealing system  620  seals fluid pressure between a partition  622  and a non-orbiting scroll member  670 . Non-orbiting scroll member  670  is designed to replace non-orbiting scroll member  70  or any other of the non-orbiting scroll members described. In a similar manner, partition  622  is designed to replace partition  22  or any other of the previously described partitions.  
         [0077]    Non-orbiting scroll member  670  includes scroll wrap  72  and it defines an annular recess  684 . Partition  622  defines an outer seal groove  686  and an inner seal groove  688 . Annular recess  684  is located between outer seal groove  686  and inner seal groove  688  and it is provided compressed fluid through fluid passage  88  which opens to a fluid pocket defined by non-orbiting scroll wrap  72  of non-orbiting scroll member  670  and orbiting scroll wrap  58  of orbiting scroll member  56 . The pressurized fluid provided through fluid passage  88  is at a pressure which is intermediate or in between the suction pressure and the discharge pressure of the compressor. The fluid pressure within recess  684  biases non-orbiting scroll member  270  towards orbiting scroll member  56  to enhance the tip sealing characteristics between the two scroll members.  
         [0078]    A flip seal  690  is disposed within outer seal groove  686  and a flip seal  692  is disposed within inner seal groove  608 . Flip seal  690  sealingly engages non-orbiting scroll member  670  and partition  622  to isolate annular recess  684  from suction pressure. Flip seal  692  sealing engages non-orbiting scroll member  670  and partition  622  to isolate annular recess  684  from discharge pressure. While not specifically illustrated in FIG. 17, non-orbiting scroll member  670  can include temperature protection system  110 . Also, while not illustrated, non-orbiting scroll member  670  can also include pressure relief system  112  if desired.  
         [0079]    Referring now to FIG. 18, a sealing system  720  in accordance with another embodiment of the present invention is illustrated. Sealing system  7020  seals fluid pressure between a cap  714  and a non-orbiting scroll member  770 . A discharge fitting  718  and a suction fitting  722  are secured to cap  714  to provide for a direct discharge scroll compressor and for providing for the return of the decompressed gas to the compressor. Non-orbiting scroll member  770  is designed to replace non-orbiting scroll member  70  or any other of the non-orbiting scroll members described. As shown in FIG. 18, a partition between the suction pressure zone and the discharge pressure zone of the compressor has been eliminated due to sealing system  720  being disposed between cap  714  and non-orbiting scroll member  770 .  
         [0080]    Non-orbiting scroll member  770  includes scroll wrap  72  and it defines an annular recess  784 , an outer seal groove  786  and an inner seal groove  788 . A passage  782  interconnects annular recess  784  with outer seal groove  786 . Annular chamber  784  is located between outer seal groove  786  and inner seal groove  788  and it is provided compressed fluid through fluid passage  88  which opens to a fluid pocket defined by non-orbiting scroll wrap  72  of non-orbiting scroll member  770  and orbiting scroll wrap  58  of orbiting scroll member  56 . The pressurized fluid provided through fluid passage  88  is at a pressure which is intermediate or in between the suction pressure and the discharge pressure of the compressor. The fluid pressure within annular chamber  784  biases non-orbiting scroll member  770  towards orbiting scroll member  56  to enhance the tip sealing characteristics between the two scroll members.  
         [0081]    A flip seal  790  is disposed within outer seal groove  786  and a flip seal  792  is disposed within inner seal groove  788 . Flip seal  790  sealing engages non-orbiting scroll member  770  and cap  714  to isolate annular recesses  784  from suction pressure. Flip seal  792  sealingly engages non-orbiting scroll member  770  and cap  714  to isolate annular recesses  784  from discharge pressure. While not illustrated in FIG. 18, non-orbiting scroll member  770  can include temperature protection system  110  and/or pressure relief system  112  if desired.  
         [0082]    Referring now to FIG. 19, the compressor illustrated in FIG. 18 is shown incorporating a vapor injection system  730 . Vapor injection system  730  includes an injection pipe  732  which extends through cap  714  and is in communication with a vapor injection passage  734  extending through non-orbiting scroll member  770 . A flat top seal  736  seals the interface between injection pipe  732  and non-orbiting scroll member  770  as well as providing a seal between vapor injection passage  734  and annular recess  786 . Vapor injection passage  734  is in communication with one or more of the fluid pockets formed by scroll wraps  72  and  58  of scroll members  770  and  56 , respectively. Vapor injection system  730  further comprises a valve  738 , which is preferably a solenoid valve, and a connection pipe  740  which leads to a source of compressed vapor. When additional capacity for the compressor is required, vapor injection system  730  can be activated to inject pressurized vapor into the compressor as is well known in the art. Vapor injection systems are well known in the art so a full discuss of the system will not be included herein. By operating vapor injection system in a pulse width modulation mode, the capacity of the compressor can be increased incrementally between its full capacity and a capacity above its full capacity as provided by vapor injection system  730 .  
         [0083]    Referring now to FIG. 20, a sealing system  820  in accordance with the present invention is illustrated. Sealing system  820  seals fluid pressure between a partition  822  and a non-orbiting scroll member  870 . Non-orbiting scroll member  870  is designed to replace non-orbiting scroll member  70  or any other of the non-orbiting scroll members described. Partition  822  is designed to replace partition member  22  or any other of the partitions described.  
         [0084]    Non-orbiting scroll member  870  includes scroll wrap  72  and it defines an annular chamber  884 . Partition  822  defines an outer seal groove  886  and an inner seal groove  888 . Annular chamber  884  is located between outer seal groove  886  and inner seal groove  888  and it is provided compressed fluid through fluid passage  88  which opens to a fluid pocket defined by non-orbiting scroll wrap  72  of non-orbiting scroll member  870  and orbiting scroll wrap  58  of orbiting scroll member  56 . The pressurized fluid provided through fluid passage  88  is at a pressure which is intermediate or in between the suction pressure and the discharge pressure of the compressor. The fluid pressure within annular chamber  884  biases non-orbiting scroll member  870  towards orbiting scroll member  56  to enhance the tip sealing characteristics between the two scroll members.  
         [0085]    A flip seal  890  is disposed within outer seal groove  886  and a flip seal  892  is disposed within inner seal groove  888 . Flip seal  890  engages non-orbiting scroll member  870  and partition  822  to isolate annular chamber  884  from suction pressure. Flip seal  892  sealingly engages non-orbiting scroll member  870  and partition  822  to isolate annular chamber  884  from discharge pressure. While not illustrated in FIG. 20, non-orbiting scroll member  870  can include temperature protection system  110 . Also, while not illustrated, non-orbiting scroll member  870  can also include pressure relief system  112  if desired.  
         [0086]    Referring now to FIG. 21, a sealing system  920  in accordance with another embodiment of the present invention is illustrated. Sealing system  920  seals fluid pressure between a cap  914  and a non-orbiting scroll member  970 . A discharge fitting  918  is secured to cap  914  to provide for a direct discharge scroll compressor. Non-orbiting scroll member  970  is designed to replace non-orbiting scroll member  70  or any other of the non-orbiting scroll members described. As shown in FIG. 21, a partition between the suction pressure zone and the discharge pressure zone of the compressor has been eliminated due to sealing system  920  being disposed between cap  914  and non-orbiting scroll member  970 .  
         [0087]    Non-orbiting scroll member  970  includes scroll wrap  72  and it defines an annular recess  984 . Disposed within annular recess  984  is a floating seal  950 . The basic concept for floating seal  950  with axial pressure biasing is disclosed in much greater detail in Assignee&#39;s U.S. Pat. No. 4,877,382, the disclosure of which is incorporated herein by reference. Floating seal  950  comprises a base ring  952 , a sealing ring  954 , an outer flip seal  990  and an inner flip seal  992 . Flip seals  990  and  992  are sandwiched between rings  952  and  954  and are held in place by a plurality of posts  956  which are an integral part of base ring  952 . Sealing ring  954  includes a plurality of holes  958  which correspond with the plurality of posts  956 . Once base ring  952 , seals  990  and  992  and sealing ring  954  are assembled, posts  956  are mushroomed over to complete the assembly of floating seal  950 . While seals  990  and  992  are described as being separate components, it is within the scope of the present invention to have a single piece component provide seals  990  and  992  with this single piece component including a plurality of holes which correspond with the plurality of posts  956 .  
         [0088]    Annular recess  984  is provided compressed fluid through fluid passage  88  which opens to a fluid pocket defined by non-orbiting scroll wrap  72  of non-orbiting scroll member  970  and orbiting scroll wrap  58  of orbiting scroll member  56 . The pressurized fluid provided through fluid passage  88  is at a pressure which is intermediate or in between the suction pressure and the discharge pressure of the compressor. The fluid pressure within annular recess  984  biases non-orbiting scroll member  970  towards orbiting scroll member  56  to enhance the tip sealing characteristics between the two scroll members. In addition, fluid pressure within annular recess  984  biases floating seal member  950  against upper cap  914  of the compressor. Sealing ring  954  engages upper cap  914  to seal the suction pressure area of the compressor from the discharge area of the compressor. Flip seal  990  sealingly engages non-orbiting scroll member  970  and rings  952  and  954  to isolate annular recess  984  from suction pressure. Flip seal  992  sealingly engages non-orbiting scroll member  970  and rings  952  and  954  to isolate annular recess  984  from discharge pressure. While not specifically illustrated in FIG. 21, non-orbiting scroll member  970  can include temperature protection system  110  and/or pressure relief system  112 .  
         [0089]    Referring now to FIG. 22, the compressor illustrated in FIG. 21 is shown incorporating a vapor injection system  930 . Vapor injection system  930  comprises a coupling  932  and an injection pipe  934 . Injection pipe  934  extends through cap  914  and is in communication with a vapor injection passage  936  extending through coupling  932 . A flip seal  938  seals the interface between coupling  932  and injection pipe  934 . Vapor injection passage  936  is in communication with a vapor injection passage  940  which extends through non-orbiting scroll member  970  to open into one or more of the fluid pockets formed by scroll wraps  72  and  58  of scroll members  970  and  56 , respectively. Vapor injection system  930  further comprises a valve  942  which is preferably a solenoid valve and a connection pipe  944  which leads to a source of compressed vapor. When additional capacity for the compressor is received, vapor injection system  930  can be activated to inject pressurized vapor into the compressor as is well known in the art. Vapor injection systems are well known in the art so a full discussion of the system will not be included herein. By operating vapor injection system  930  in a pulse width modulation mode, the capacity of the compressor can be increased incrementally between its full capacity and a capacity above its full capacity as provided by vapor injection system  930 .  
         [0090]    Referring now to FIGS.  23 A- 23 H, various configurations for the seal grooves described above are illustrated. FIG. 23A illustrates a seal groove  1100  having a rectangular configuration. FIG. 23B illustrates a seal groove  1110  having one side defining a straight portion  1112  and a tapered portion  1114 . This is the preferred groove geometry with the edge of the seal assembled within groove  1110  sealing against either one of portions  1112  or  1114 . The other side of groove  1110  is a straight wall. FIG. 23C illustrates a seal groove  1120  having one side defining a first tapered portion  1122  and a second tapered portion  1124 . The edge of the seal assembled within groove  1120  seals against either one of portions  1122  or  1124 . The other side of groove  1120  is a straight wall.  
         [0091]    [0091]FIG. 23D illustrates a seal groove  1130  having one side defining a reverse tapered wall  1132 . The edge of the seal assembled within groove  1130  seals against reverse tapered wall  1132 . The other side of groove  1130  is a straight wall. FIG. 23E illustrates a seal groove  1140  having one wall defining a first reverse tapered portion  1142  and a second reverse tapered portion  1144 . The edge of the seal assembled within groove  1140  seals against either one of portions  1142  or  1144 . The other side of groove  1140  is a straight wall. FIG. 23F illustrates a seal groove  1150  having one side defining a reverse tapered portion  1152  and a tapered portion  1154 . The edge of the seal assembled within groove  1150  seals against either one of portions  1152  or  1154 . The other side of groove  1150  is a straight wall.  
         [0092]    [0092]FIG. 23G illustrates a seal groove  1160  having one side defining a reverse tapered portion  1162 , a straight portion  1164  and a tapered portion  1166 . The edge of the seal assembled within groove  1160  seals against either one of portions  1162 , 1164  or  1166 . The other side of seal groove  1160  is a straight wall. FIG. 23H illustrates a seal groove  1170  having one side defining a curved wall  1172 . The edge of the seal assembled within groove  1170  seals against curved wall  1172 . The other side of seal groove  1170  is straight.  
         [0093]    Referring now to FIGS. 24 and 25, flip seal  90  is illustrated. FIG. 24 illustrates flip seal  90  in an as molded condition. Flip seal  90  is molded preferably from a Teflon® material containing 10% when it is interfacing with a steel component. Flip seal  90  is molded in an annular shape as shown in FIG. 24 with a notch  98  extending into one surface thereof. Notch  98  facilitates the bending of flip seal  90  into its L-shaped configuration as shown in FIG. 25. While FIGS. 24 and 25 illustrate flat top seal  90 , it is to be understood that flip seals  92 ,  94 ,  490 ,  492 ,  590 ,  592 ,  690 ,  692 ,  790 ,  792 ,  890 ,  892 ,  990  and  992  are all manufactured with notch  98 .  
         [0094]    While not specifically illustrated, vapor injection systems  730  and  930  can be designed to provide for delayed suction closing instead of vapor injection. When designed for delayed suction closing, system  730  and  930  would extend between one of the closed pockets defined by the scroll wraps and the suction area of the compressor. The delayed suction closing systems provide for capacity modulation as is well known in the art and can also be operated in a pulse width modulation manner. In addition, the vapor injection system illustrated in FIGS. 19 and 22 can be incorporated into any of the embodiments of the invention illustrated.  
         [0095]    While the above detailed description describes the preferred embodiment of the present invention, it should be understood that the present invention is susceptible to modification, variation and alteration without deviating from the scope and fair meaning of the subjoined claims.