Patent Abstract:
A scroll type compressor includes a housing, a fixed scroll member, a movable scroll member, a discharge port, a cooling chamber and a gas cooler. The fixed scroll member is fixed to the housing. The movable scroll member is accommodated in the housing and defining a compression region with the fixed scroll member where gas is compressed by orbiting the movable scroll member relative to the fixed scroll member. The compressed gas is discharged from the compression region through the discharge port. The cooling chamber for cooling the compressed gas is disposed in the vicinity of the compression region in the housing. The gas cooler for passing the gas discharged from the discharge port extends along the cooling chamber.

Full Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a scroll type compressor, more particularly to a scroll type compressor that compresses gas supplied to a fuel cell.  
           [0002]    There are various types of compressors such as a screw type compressor, a rotary type compressor and a scroll type compressor. Since the scroll type compressor is small, light, and quiet without much vibration and noise, the scroll type compressor is widely used for freezing and air conditioning among others. The scroll type compressor produces heat in a compression cycle. In a prior art as described in Unexamined Japanese Patent Publication No.  8-247056 , a cooling chamber is defined to the side which gas in a compression chamber is discharged in order to remove the heat.  
           [0003]    [0003]FIG. 12 shows a cross-sectional view in an axial direction of a conventional scroll type compressor  100 . In the compressor  100 , a housing is constituted of a front casing  101 , an end plate  102  and a rear casing  103 . The end plate  102  is placed on one side of the front casing  101 , to which gas is discharged. The rear casing  103  is placed on the other side of the front casing  101  where a motor which is not shown is connected. A discharge port  104  is formed at the center of the front casing  101 . A discharge valve  108  which opens toward the end plate  102  side only is provided at the discharge port  104 . A gas passage  112  is formed to penetrate the end plate  102  on the side of the discharge port  104 , to which the gas is discharged. A cooling chamber  120  is defined between the front casing  101  and the end plate  102 . A fixed scroll of a volute shape  105  extends from an inner wall  107  of the front casing  101  to face the side of the motor in a standing manner. On the other hand, a drive shaft  109 , which is connected to a rotary shaft of the motor, is in the shape of crank. One end of the drive shaft  109  is rotatably supported by the rear casing  103  on the side of the motor. The other end of the drive shaft  109 , to which the gas is discharged, is rotatably supported by an orbital plate  111 . An orbital scroll of a volute shape  110  extends from the orbital plate  111  toward the front casing  101 . The fixed scroll  105 , the inner wall  107 , the orbital scroll  110  and the orbital plate  111  cooperatively form compression chambers  106 . The compression chambers  106  are defined in a volute shape.  
           [0004]    Still referring to FIG. 12, when the drive shaft  109  is rotated by the motor, the orbital scroll  110  orbits. Gas such as air in the compression chambers  106  is moved toward the center of the fixed scroll  105  as is compressed by orbital movement of the orbital scroll  110 . The temperature of the gas rises during the compression cycle. Then, the compressed gas is discharged outside the compressor  100  through the discharge port  104  and the gas passage  112 .  
           [0005]    Coolant such as cooling water flows into the cooling chamber  120  through an inlet which is not shown. The cooling chamber  120  is defined in the vicinity of the compression chambers  106  and the gas passage  112 . Therefore, heat of the gas compressed in the compression chambers  106  and the gas discharged into the gas passage  112  is conducted to the coolant. The temperature of the coolant rises due to the heat conduction, and the coolant flows outside the compressor  100  through an outlet which is not shown.  
           [0006]    In the above prior art, however, the gas is discharged outside the compressor  100  through the gas passage  112  which extends in the axial direction of the drive shaft  109 . The gas passage  112  is short in length. Accordingly, when the discharge gas passes through the gas passage  112 , heat exchange between the discharge gas and the coolant in the cooling chamber  120  is not sufficiently performed. Therefore, temperature of the discharge gas is not sufficiently decreased.  
           [0007]    When the temperature of the discharge gas is high, if a device whose heat resistance is low is placed in the vicinity of the gas passage  112 , the device may have trouble. For example, when the scroll type compressor  100  is used to compress the gas supplied to the fuel cell, a hydrogen ion exchange membrane is placed below the compressor  100 . Since the hydrogen ion exchange membrane is low in heat resistance, the discharge gas in high temperature may cause trouble.  
           [0008]    Since the discharge gas in high temperature is small in density, mass flow of the gas (kg/hour) decreases. Namely, compression efficiency is lowered. When the discharge gas is utilized, a predetermined mass of the gas per time unit may be required. In this case, if work of the compressor  100  is increased to reserve the predetermined mass of the gas, the compressor  100  or the motor driving the compressor  100  is required to be increased in size.  
           [0009]    To decrease the temperature of the discharge gas without changing the work, another heat exchanger may be connected below the scroll type compressor  100 . In this case, however, extra space for placing another heat exchanger is required.  
         SUMMARY OF THE INVENTION  
         [0010]    The present invention addresses a scroll type compressor whose discharge gas is low in temperature.  
           [0011]    According to the present invention, a scroll type compressor includes a housing, a fixed scroll member, a movable scroll member, a discharge port, a cooling chamber and a gas cooler. The fixed scroll member is fixed to the housing. The movable scroll member is accommodated in the housing and defining a compression region with the fixed scroll member where gas is compressed by orbiting the movable scroll member relative to the fixed scroll member. The compressed gas is discharged from the compression region through the discharge port. The cooling chamber for cooling the compressed gas is disposed in the vicinity of the compression region in the housing. The gas cooler for passing the gas discharged from the discharge port extends along the cooling chamber. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0012]    The features of the present invention that are believed to be novel are set forth with particularity in the appended claims. The invention together with objects and advantages thereof, may best be understood by reference to the following description of the presently preferred embodiments together with the accompanying drawings in which:  
         [0013]    [0013]FIG. 1 is a diagram in a cross-sectional view in an axial direction illustrating the scroll type compressor of the first preferred embodiment according to the present invention;  
         [0014]    [0014]FIG. 2 is a diagram in a cross-sectional view at a line I-I in FIG. 1;  
         [0015]    [0015]FIG. 3 is a diagram in a front view illustrating a casing for gas cooler of the scroll type compressor of the first preferred embodiment according to the present invention;  
         [0016]    [0016]FIG. 4 is a diagram in a front view illustrating a casing for gas cooler of the scroll type compressor of the second preferred embodiment according to the present invention;  
         [0017]    [0017]FIG. 5 is a diagram in a front view illustrating a casing for gas cooler of the scroll type compressor of the third preferred embodiment according to the present invention;  
         [0018]    [0018]FIG. 6 is a diagram in a front view illustrating a casing for gas cooler of the scroll type compressor of the fourth preferred embodiment according to the present invention;  
         [0019]    [0019]FIG. 7 is a diagram in a front view illustrating a casing for gas cooler of the scroll type compressor of the fifth preferred embodiment according to the present invention;  
         [0020]    [0020]FIG. 8 is a diagram in a cross-sectional view in an axial direction illustrating the scroll type compressor of the sixth preferred embodiment according to the present invention;  
         [0021]    [0021]FIG. 9 is a diagram in a cross-sectional view in an axial direction illustrating the scroll type compressor of the seventh preferred embodiment according to the present invention;  
         [0022]    [0022]FIG. 10 is a diagram in a cross-sectional view in an axial direction illustrating the scroll type compressor of the eighth preferred embodiment according to the present invention;  
         [0023]    [0023]FIG. 11 is a diagram in a cross-sectional view in an axial direction illustrating the scroll type compressor of the ninth preferred embodiment according to the present invention; and  
         [0024]    [0024]FIG. 12 is a diagram in a cross-sectional view in an axial direction illustrating a conventional scroll type compressor. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0025]    A scroll type compressor according to a first preferred embodiment of the present invention will be described with reference to FIGS. 1 through 3. As a matter of convenience, a discharge direction and a motor direction are referred to as ‘front’ and ‘rear’ respectively.  
         [0026]    As shown in FIG. 1, a scroll type compressor  1  is used to compress air supplied to a fuel cell as oxidizing agent. The scroll type compressor  1  is driven by a motor which is not shown. In the first preferred embodiment, the hull of the scroll type compressor  1  is constituted of a housing  2  and a gas cooler  3  placed in front of the housing  2 .  
         [0027]    Still referring to FIG. 1, the housing  2  is constituted of a front casing  4  and a rear casing  5 . A recess  40  is formed in the front surface of the front casing  4 . The rear casing  5  is placed in the rear of the front casing  4 . Note that these members are made of aluminum alloy.  
         [0028]    A fixed scroll of a volute shape  41  is provided on an inner wall  45  of the front casing  4  so as to extend rearward. The first discharge port  42  is formed at the center of volute of the fixed scroll  41 , and a discharge valve  43  that opens only in the discharge direction is provided at the first discharge port  42 . Further, a cooling chamber  44  is defined between the recess  40  of the front casing  4  and the gas cooler  3 .  
         [0029]    As shown in FIG. 2, the cooling chamber  44  is formed in the letter U shape surrounding the first discharge port  42 . A first inlet  440 , which cooling water flows in, is formed at one end of the cooling chamber  44 , and a first outlet  441 , from which the cooling water flows out, is formed at the other end. Note that the cooling chamber  44  constitutes a part of a cooling circuit. A radiator which is not shown, for cooling high temperature cooling water flowed out from the first outlet  441 , a pump which is not shown, for flowing the cooling water that has been cooled through the first inlet  440 , and the like are placed in the cooling circuit. Pure water generated due to cell reaction in the fuel cell is used as the cooling water that circulates the cooling circuit.  
         [0030]    On the other hand, as shown in FIG. 1, one end of a drive shaft  50  is rotatably supported in the rear end of the rear casing  5  through ball bearings. The drive shaft  50  is in a crank shape. The other end of the drive shaft  50  is rotatably supported in an orbital plate  51  in a disc shape through bearings. A balance weight  52  for balancing during rotation of the drive shaft  50  is also formed on the other end of the drive shaft  50 . An orbital scroll of a volute shape  53  extends from the orbital plate  51  in the discharge direction. Note that the rear end of the drive shaft  50  is connected with a motor rotation shaft which is not shown. Further, the end of the fixed scroll  41  extending from the inner wall  45  of the front casing  4  contacts the surface of the orbital plate  51 . On the other hand, the end of the orbital scroll  53  contacts the inner wall  45  of the front casing  4 . In other words, the fixed scroll  41  and the orbital scroll  53  are engaged between the inner wall  45  and the orbital plate  51  so as to overlie alternately with each other at a position where the scrolls are relatively rotated by 180° degrees. The inner wall  45 , the fixed scroll  41 , the orbital plate  51  and the orbital scroll  53  define compression chambers  46  as a compression region. In addition, a part of the front end of an axis  54  for preventing rotation is rotatably supported in an outer circumferential side of the orbital plate  51  through ball bearings. The axis  54  is also in a crank shape with a divided front end similarly to the drive shaft  50 . A balance weight  55  is formed on a part of the divided front end. Furthermore, the rear end of the axis  54  is rotatably supported in the rear casing  5  through ball bearings.  
         [0031]    Still referring to FIG. 1, the gas cooler  3  is constituted of a first casing  6  formed in front of the front casing  4  and an end plate  7  placed on the front end of the first casing  6 . Note that these members are made of aluminum alloy.  
         [0032]    As shown in FIG. 3, the first casing  6  is in a dish shape that opens forward. A first spiral groove  60  of a spiral shape is continuously formed inside the first casing  6 . A first gas passage  61  is formed between the first spiral groove  60  and the end plate  7 . The first gas passage  61  is arranged in a spiral shape between the first discharge port  42  at the center and the second discharge port  64  of an outermost gas passage.  
         [0033]    As shown in FIG. 1, when the motor which is not shown rotates the drive shaft  50 , its rotation force is transmitted to the orbital plate  51  to allow the orbital plate  51  to orbit about the drive shaft  50 . Then, the orbital scroll  53  performs an orbital motion along the fixed scroll  41 . Note that the rotation of the orbital scroll  53  is prevented by the axis  54 .  
         [0034]    Still referring to FIG. 1, when the orbital scroll  53  starts the orbital motion, air is taken in from an air intake port which is not shown, to be flowed into outermost compression chambers  460  of the compression chambers  46  connected with the air intake port. The air in the compression chambers  46  moves spirally toward a center  461  of volute of the fixed scroll  41 . Air compression is performed in this process. Compressed air reaches the center  461  of the volute to be flowed into the first gas passage  61  pushing away the discharge valve  43 . The air moves spirally in the first gas passage  61  in an outermost direction and is supplied to the fuel cell through the second discharge port  64  of the outermost gas passage.  
         [0035]    The cooling water flows into the cooling chamber  44  from the first inlet  440  and absorbs heat of the air being compressed in the compression chamber  46  and discharge air in the first gas passage  61 , and flows out from the first outlet  441 . The cooling water flowed out from the first outlet  441  is cooled by the radiator and is flowed into the cooling chamber  44  again by the pump. Specifically, the cooling water circulates within the cooling circuit while repeating increase and decrease in temperature. However, a part of the cooling water flowed from the first outlet  441  is discarded, and the pure water generated in the fuel cell is appropriately refilled into the cooling circuit by the discarded amount.  
         [0036]    Note that the gas cooler  3  of this embodiment is fabricated in a process that the first casing  6  forming the first spiral groove  60  is cast in advance and the end plate  7  is then screwed by a bolt from the above. Note that a rubber member which is not shown, is located between the first casing  6  and the end plate  7  to secure airtightness of the first gas passage  61 .  
         [0037]    A scroll type compressor according to a second preferred embodiment of the present invention will be described with reference to FIG. 4. The scroll type compressor  1  of this embodiment is one where first dividing fins  65  for dividing the gas flow in parallel are provided in the first gas passage  61  in a standing manner. Other configuration and manufacturing method are the same as the first embodiment. Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0038]    Still referring to FIG. 4, the first dividing fins  65  for dividing gas passage extending along the first gas passage  61  are provided in a standing manner between the first discharge port  42  at the center and the second discharge port  64  of the outermost gas passage. The first dividing fins  65  divide the gas flow discharged from the first discharge port  42 . Furthermore, the first gas passage  61  of this embodiment is arranged in a wide area so as to contact an entire front surface of the cooling chamber  44  which is shown in a dotted line arranged in the rear side. With the first dividing fins  65  provided in a standing manner and with an increased contact area with the cooling chamber  44 , the heat conducting area of the first gas passage  61  increases. Thus, the cooling efficiency of the first gas passage  61  of this embodiment is improved.  
         [0039]    A scroll type compressor according to a third preferred embodiment of the present invention will be described with reference to FIG. 5. The scroll type compressor  1  of this embodiment is one where the dividing fins  65  for dividing the gas flow in two ways are provided in the first gas passage  61  in a standing manner. Other configuration and manufacturing method are the same as the first embodiment. Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0040]    Still referring to FIG. 5, the first dividing fins  65  are arranged between the first discharge port  42  at the center and the second discharge port  64  of the outermost gas passage. The first dividing fins  65  define the area from the first discharge port  42  to the second discharge port  64  in eight courses in total having four courses anticlockwise and four courses clockwise. When the gas flow is divided in two ways, the gas flow path from the first discharge port  42  to the second discharge port  64  becomes short in length. Accordingly, the pressure loss becomes smaller than the case where, for example, the fins are provided spirally without dividing the gas flow.  
         [0041]    A scroll type compressor according to a fourth preferred embodiment of the present invention will be described with reference to FIG. 6. The scroll type compressor  1  of this embodiment is one where the dividing fins  65  for radially dividing the gas flow are provided in the first gas passage  61  in a standing manner. Other configuration and manufacturing method are the same as the first embodiment. Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0042]    Still referring to FIG. 6, the first dividing fins  65  are arranged in a scattering manner between the first discharge port  42  at the center and the second discharge port  64  of the outermost gas passage. The first dividing fins  65  radially divide the discharge gas discharged from the first discharge port  42 . Accordingly, in the first gas passage  61  of this embodiment, the pressure loss becomes even smaller.  
         [0043]    A scroll type compressor according to a fifth preferred embodiment of the present invention will be described with reference to FIG. 7. The scroll type compressor  1  of this embodiment is one where bars  67  for generating turbulence in the gas flow are arranged in the first gas passage  61 . Other configuration and manufacturing method are the same as the first embodiment. Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0044]    Still referring to FIG. 7, the bars  67  for generating turbulence in the gas flow are arranged in a scattering manner between the first discharge port  42  at the center and the second discharge port  64  of the outermost gas passage. The bars  67  causes turbulence in the gas discharged from the first discharge port  42 . When the turbulence is generated, the residence time of the discharge gas in the first gas passage  61  becomes long accordingly. Specifically, the cooling time of the discharge gas becomes long accordingly. Therefore, the cooling efficiency is improved according to this embodiment.  
         [0045]    A scroll type compressor according to a sixth preferred embodiment of the present invention will be described with reference to FIG. 8. The scroll type compressor  1  of this embodiment is one where cooling fins  62  are provided in the first gas passage  61 . Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0046]    Still referring to FIG. 8, in the scroll type compressor  1  of this embodiment, the cooling fins  62  are provided in a standing manner in the first gas passage  61 . Further, the inside of the cooling fins  62  is a part of the cooling chamber  44 , in which the cooling water circulates. In other words, grooves  63  are formed on rear sides of the cooling fins  62 , and the cooling chamber  44  is defined between the grooves  63  and the recess  40  of the front casing  4 .  
         [0047]    The gas cooler  3  of this embodiment is fabricated in a process that the first casing  6  provided with the cooling fins  62  is cast in advance and the end plate  7  is then screwed by the bolt from the above. The configuration of the other part is the same as the first embodiment.  
         [0048]    A scroll type compressor according to a seventh preferred embodiment of the present invention will be described with reference to FIG. 9. The scroll type compressor  1  of this embodiment is one where the gas cooler  3  is integrally formed with the housing  2 . Specifically, the first gas passage  61  and the cooling passage  47  are arranged in the housing  2  in a dual spiral shape. Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0049]    Still referring to FIG. 9, the housing  2  of the scroll type compressor  1  of this embodiment is constituted of the front casing  4  where a dual spiral groove  48  is formed in the front surface, the end plate  7  placed in front of the front casing  4  while covering the dual spiral groove  48 , and the rear casing  5  placed in the rear of the front casing  4 .  
         [0050]    In the scroll type compressor  1  of this embodiment, dual spiral passages are formed between the end plate  7  and the dual spiral groove  48  in a perpendicular direction to the axial direction. One of the passages is the first gas passage  61 , and the other one is the cooling passage  47 . The cooling water flows into the cooling passage  47  from a second inlet  470  provided in the outermost area of the front casing  4  and, moves spirally in an innermost direction, and flows out from a second outlet  471 . On the other hand, the discharge gas flows into the first gas passage  61  from the first discharge port  42 , moves spirally in the outermost direction which is an opposite direction to the cooling water, is discharged outside the compressor  1  from the second discharge port  64  of the outermost gas passage, and is supplied to the fuel cell.  
         [0051]    In this embodiment, the first gas passage  61  and the cooling passage  47  are fabricated in a process where the front casing  4  provided with the dual spiral groove  48  is cast in advance and the end plate  7  is then screwed by the bolt from the above. Note that the rubber member is located between the front casing  4  and the end plate  7  to secure airtightness of the first gas passage  61  and liquid-tightness of the cooling passage  47 . The configuration of the other part is the same as the first embodiment.  
         [0052]    A scroll type compressor according to a eighth preferred embodiment of the present invention will be described with reference to FIG. 10. The scroll type compressor  1  of this embodiment is one where an auxiliary cooling chamber  81  is further provided in front of a second gas passage  91 . Note that the same reference numerals are used for the members corresponding to those of the first embodiment.  
         [0053]    Still referring to FIG. 10, the gas cooler  3  of the scroll type compressor  1  of this embodiment is constituted of a second casing  9  placed in front of the front casing  4 , a third casing  8  placed in front of the second casing  9 , and the end plate  7  placed in front of the third casing  8 . The second casing  9  is for gas passage. The third casing  8  is for cooling chamber.  
         [0054]    The second casing  9  is in a dish shape that opens forward. Second spiral grooves  90  are formed in the second casing  9 . The second gas passage  91  is formed between the second spiral grooves  90  and the third casing  8 . The third casing  8  is also in a dish shape that opens forward. Third spiral grooves  80  are formed in the third casing  8  as well. The auxiliary cooling camber  81  is formed between the third spiral grooves  80  and the end plate  7 . Furthermore, the first outlet  441  of the cooling chamber  44  and a third inlet  810  of the auxiliary cooling chamber  81  are connected by a connecting pipe  82 . The discharge gas flows into the second gas passage  91  from the first discharge port  42 , moves spirally in the outermost direction, is discharged outside the compressor  1  from a second discharge port  94  of the outer most gas passage, and is supplied to the fuel cell. On the other hand, the cooling water flows into the auxiliary cooling chamber  81  from the cooling chamber  44  through the third inlet  810 , moves spirally in the innermost direction, and flows outside the compressor  1  from a third outlet  811 .  
         [0055]    The gas cooler  3  of this embodiment is fabricated in a process that the second casing  9  and the third casing  8  are cast first, the third casing  8  is screwed in front of the second casing  9  by the bolt, and the end plate  7  is then screwed by the bolt in front of the third casing  8 . Note that the rubber members are located between the second casing  9  and the third casing  8  and between the third casing  8  and the end plate  7  respectively to secure airtightness of the second gas passage  91  and liquid-tightness of the auxiliary cooling chamber  81 . The configuration of the other part is the same as the first embodiment.  
         [0056]    A scroll type compressor according to a ninth preferred embodiment of the present invention will be described with reference to FIG. 11. The scroll type compressor  1  of this embodiment is one where the auxiliary cooling chamber  81  is provided in front of the second gas passage  91  similarly to the eighth preferred embodiment. At the same time, the compressor  1  is one where the auxiliary cooling fins  93  extending from the front area of the second gas passage  91  toward the auxiliary cooling chamber  81  and the cooling fins  95  extending from the rear surface of the second gas passage  91  toward the cooling chamber  44  are arranged. Note that the same reference numerals are used for the members corresponding to those of the eighth embodiment.  
         [0057]    Still referring to FIG. 11, the gas cooler  3  of the scroll type compressor  1  of this embodiment is constituted of the second casing  9  placed in front of the front casing  4 , the third casing  8  placed in front of the second casing  9 , and the end plate  7  placed at the front end of the third casing  8 .  
         [0058]    The second casing  9  is in a dish shape that opens forward. Second dividing fins  92  for dividing the second gas passage  91 , which extend forward and cooling fins  95  for dividing the cooling chamber  44 , which extend backward are severally provided on the bottom wall of the second casing  9  in a standing manner. The third casing  8  is also in a dish shape that opens forward. The auxiliary cooling fins  93  extending forward and the second dividing fins  92  extending backward are severally provided on the bottom wall of the third casing  8  in a standing manner.  
         [0059]    Then, the second gas passage  91  is defined in courses by the second dividing fins  92  that extend from the front and the rear. The cooling chamber  44  is also defined in courses by the cooling fins  95  that extend from the front. Furthermore, the auxiliary cooling chamber  81  is defined in courses by the auxiliary cooling fins  93  that extend from the rear. The configuration of the other part and the manufacturing method is the same as the eighth embodiment.  
         [0060]    The discharge gas flows into the second gas passage  91  from the first discharge port  42 . Then the discharge gas spirally moves in the second gas passage  91  widening its diameter to the second discharge port  94  while being divided in parallel by the second dividing fins  92 . Then, the discharge gas is discharged outside the compressor  1  from the second discharge port  94  and is supplied to the fuel cell. On the other hand, the cooling water flows into the auxiliary cooling chamber  81  through the third inlet  810  after moving through the cooling chamber  44  while being divided in parallel by the cooling fins  95 . Then, the cooling water spirally moves reducing its diameter in the auxiliary cooling chamber  81  while being divided in parallel by the auxiliary cooling fins  93 . Thereafter, the cooling water flows outside the compressor  1  from the third outlet  811 .  
         [0061]    The second dividing fins  92  are arranged in the compressor  1  of this embodiment. The cooling fins  95  and the auxiliary cooling fins  93  are also arranged. For this reason, the heat conducting area between the second gas passage  91  and the cooling chamber  44  and between the second gas passage  91  and the auxiliary cooling chamber  81  are increased. Therefore, the cooling efficiency of the discharge gas is further improved.  
         [0062]    Note that the auxiliary cooling chamber  81  is arranged and the auxiliary cooling fins  93  are inserted therein in this embodiment. However, the compressor  1  may be embodied in a mode where the auxiliary cooling chamber  81  is not arranged. Specifically, the auxiliary cooling fins  93  may be provided in a standing manner at the front end of the compressor  1  in an open state. The cooling efficiency of the discharge gas is improved in this mode as well because the heat conducting area to the atmosphere is increased.  
         [0063]    The scroll type compressor of the present invention is particularly suitable for compressing gas supplied to a fuel cell. In the automobile industry, expectation for an electric vehicle having the fuel cell as a drive source has been rising. A small and lightweight scroll type compressor is drawing attention as a compressor of the gas supplied to the fuel cell.  
         [0064]    In the fuel cell, the gas of a desired mass flow needs to be supplied in accordance with an amount of electric power generation. According to the scroll type compressor of the present invention, since the temperature of the gas supplied to the fuel cell is low, the mass flow of the gas is large. Therefore, the gas of a desired mass flow can be easily supplied to the fuel cell.  
         [0065]    Further, when the gas is supplied to the fuel cell, the gas needs to be humidified in advance before cell reaction. For this purpose, a hydrogen ion exchange membrane is provided at the exit of the discharge port of the compressor as described above, whose heat-resistant temperature is about 140° C. There exists a part having the heat-resistant temperature of about 100° C. among parts constituting the fuel cell. Therefore, the gas needs to be cooled by the compressor in advance to a level that can fulfill the temperature conditions. According to the scroll type compressor of the present invention, the gas supplied to the fuel cell can be cooled to the level that fulfills the foregoing conditions, and the fuel cell and its attached equipment can be protected from heat.  
         [0066]    Moreover, pure water is generated as a by-product of the cell reaction in the fuel cell, and the pure water can be effectively used as coolant supplied to the cooling chamber.  
         [0067]    Note that the gas supplied to the fuel cell is air and oxygen as an oxidizing agent, and hydrogen as fuel. Any type of the gas can be compressed by the scroll type compressor of the present invention.  
         [0068]    In the embodiments, the present invention is applied to the scroll type compressor. However, the present invention may be applied to other type of compressors.  
         [0069]    According to the present invention, a scroll type compressor whose discharge gas is low in temperature is offered.  
         [0070]    In the foregoing, modes of embodiment of the scroll type compressor of the present invention have been described, but the embodiment is not particularly limited to the foregoing one. The present invention may be embodied in various changes and improvement that can be performed by those skilled in the art.

Technology Classification (CPC): 5