Abstract:
A heat recovery system includes an electric rotary device, a heat exchanger, a pipe and a reservoir. The electric rotary device has a stator core and a housing. The stator core is wounded with a coil. The heat exchanger provides heat exchanging between first and second heat medium. The first heat medium is in contact with the coil and absorbs heat from the coil. The pipe connects the electric rotary device to the heat exchanger and transfers the first heat medium. The reservoir is formed in the housing and stores the first heat medium. The electric rotary device has an insulative body. The insulative body prevents heat of the first heat medium from being dissipated outside of the housing.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a heat recovery system for a vehicle. 
         [0002]    Japanese Patent Application Publication 2008-148464 discloses a motor used to drive wheels of a vehicle. This motor has a stator core and a rotor in a housing of the motor. A coil is wound around the stator core and the rotor is mounted on a shaft of the motor. Annular jackets are fixed to the stator core on opposite sides thereof at positions adjacent to the coil. A passage of oil for cooling the coil is formed in each jacket. The jacket has formed therein an inlet and an outlet of the oil passage, and a pipe is connected to the inlet and the outlet. The housing may reserve oil flowing out from the outlet of the oil passage. Another pipe is connected in the bottom of the housing. A pump circulating oil and a reservoir tank storing oil are connected in the pipe. 
         [0003]    In the above motor, however, the heat recovered from the coil by the oil is only wasted without being utilized for air-conditioning or improvement of fuel efficiency of the vehicle. 
         [0004]    For effective utilization of the heat wasted heretofore, a heat exchanger may be connected through pipes to the motor for heat exchanging between the heated oil and any other medium, thereby making a heat recovery system. If air is used as the medium to be heated in the heat exchanging, the air may be utilized for air conditioning. 
         [0005]    In the above motor, jacket is disposed adjacent to the coil, but the oil in the jacket is not in direct contact with the coil. Therefore, heat of the coil isn&#39;t conducted to the oil effectively and heat of the coil is not recovered efficiently. This problem is true of a generator substituted for the motor. 
         [0006]    In the above motor, no insulator is provided for insulating the housing, so that heat of the oil is dissipated out of the housing. If the motor is used with the aforementioned heat exchanger, the heat developed by the motor or generator cannot be transmitted effectively to the heat exchanger. 
         [0007]    The present invention that has been made in light of the above problem is directed to providing a heat recovery system that collects heat of an electric rotary device and transmits the collected heat to a heat exchanger efficiently. 
       SUMMARY OF THE INVENTION 
       [0008]    A heat recovery system includes an electric rotary device, a heat exchanger, a pipe and a reservoir. The electric rotary device has a stator core and a housing. The stator core is wound with a coil. The heat exchanger provides heat exchanging between first and second heat media. The first heat medium is in contact with the coil and absorbs heat therefrom. The pipe connects the electric rotary device to the heat exchanger and transfers therethrough the first heat medium. The reservoir is formed in the housing and stores therein the first heat medium. The electric rotary device has an insulative body. The insulative body prevents the heat of the first heat medium from being dissipated outside the housing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    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: 
           [0010]      FIG. 1  is a longitudinal sectional view showing a configuration of a heat recovery system according to a first preferred embodiment of the present invention; 
           [0011]      FIG. 2  is a fragmentary partially enlarged longitudinal sectional view showing a part of the heat recovery system according to the first preferred embodiment of the present invention; 
           [0012]      FIG. 3  is also a fragmentary partially enlarged longitudinal sectional view showing another part of the heat recovery system according to the first preferred embodiment of the present invention; 
           [0013]      FIG. 4  is a front view showing a enlarged portion of configuration of a heat recovery system according to the first preferred embodiment of the present invention; 
           [0014]      FIG. 5  is a front view similar to  FIG. 4 , but showing a heat recovery system according to a second preferred embodiment of the present invention; 
           [0015]      FIG. 6  is a front view similar to  FIG. 4 , but showing a heat recovery system according to a third preferred embodiment of the present invention; 
           [0016]      FIG. 7  is a longitudinal sectional view similar to  FIG. 2 , but showing a heat recovery system according to a fourth preferred embodiment of the present invention; 
           [0017]      FIG. 8  is a longitudinal sectional view similar to  FIG. 2 , but showing a heat recovery system according to a fifth preferred embodiment of the present invention; 
           [0018]      FIG. 9  is a longitudinal sectional view similar to  FIG. 3 , showing a heat recovery system according to a sixth preferred embodiment of the present invention; 
           [0019]      FIG. 10  is a longitudinal sectional view similar to  FIG. 3 , but showing a heat recovery system according to a seventh preferred embodiment of the present invention; 
           [0020]      FIG. 11  is a longitudinal sectional view similar to  FIG. 3 , but showing a heat recovery system according to an eighth preferred embodiment of the present invention; 
           [0021]      FIG. 12  is a longitudinal sectional view similar to  FIG. 3 , but showing a heat recovery system according to a ninth preferred embodiment of the present invention; 
           [0022]      FIG. 13  is a longitudinal sectional view similar to  FIG. 2 , but showing a reference example of a heat recovery system; 
           [0023]      FIG. 14  is a longitudinal sectional view similar to  FIG. 2 , but showing a heat recovery system according to a tenth preferred embodiment of the present invention; 
           [0024]      FIG. 15  is a fragmentary partially enlarged longitudinal sectional view showing a part of a heat recovery system according to a eleventh preferred embodiment of the present invention; 
           [0025]      FIG. 16  is a fragmentary partially enlarged longitudinal sectional view similar to  FIG. 15 , but showing a heat recovery system according to a twelfth preferred embodiment of the present invention; 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0026]    The following will describe a heat recovery system according to the first embodiment of the present invention as used for a vehicle with reference to  FIGS. 1 through 4 . 
         [0027]    Referring to  FIG. 1 , the heat recovery system includes a motor  1  as a electric rotary device, a heat exchanger  2  and pipes  3 A,  3 B. The pipes  3 A,  3 B connect the motor  1  to the heat exchanger  2  and allows oil O as first heat exchange medium to flow therebetween. 
         [0028]    The motor  1  has a housing  4  and a rotary shaft  5  rotatably supported by the housing  4  via bearings  4 A. A stator core  7  is fixed to the inner periphery of the housing  4  through an insulator  6  as an auxiliary insulative body. Rubber is used as the material of the insulator  6 . The stator core  7  has a plurality of slots spaced equiangularly and extending axially of the stator core  7  and a coil  8  is wound in the slots of the stator core  7 . A rotor  9  is fixedly mounted on the rotary shaft  5  inside the stator core  7 . A permanent magnet (not shown) is fixed in the rotor  9 . 
         [0029]    Annular heat absorbing jackets  10 ,  11  are fixed to the stator core  7  on the opposite axial ends thereof. 
         [0030]    Referring to  FIG. 2  showing only the heat absorbing jacket  11 , the heat absorbing jacket  10 ,  11  has formed therein a passage  10 A,  11 A of oil O, covering the coil  18 . Referring to  FIG. 1 , the stator core  7  is fixed to the inner periphery of the housing  4  through an insulator  6 , and the heat absorbing jacket  10 ,  11  is fixed to the stator core  7 , so that the heat absorbing jacket  10 ,  11  is also insulated from the housing  4  by the insulator  6 . 
         [0031]    The heat absorbing jackets  10 ,  11  have inlets  10 B,  11 B for the oil passages  10 A,  11 A extending upward and opened at the top, respectively. As shown in  FIG. 1 , the pipe  3 B extending from the heat exchanger  2  is branched for connection to the inlets  10 B,  11 B. The oil O from the heat exchanger  2  is transferred into the oil passages  10 A,  11 A through the pipe  3 B and the inlets  10 B,  11 B. The heat absorbing jackets  10 ,  11  have at the bottom thereof outlets  10 C,  11 C opened downward, respectively. The oil O in the passages  10 A,  11 A flows out therefrom through the outlets  10 C,  11 C. The diameter of the outlets  10 C,  11 C is smaller than that of the inlets  10 B,  11 B. 
         [0032]    Referring to  FIG. 3 , a tank  12  is disposed in the bottom of the housing  4  at a position corresponding to the heat absorbing jacket  10 ,  11 . The volume of the tank  12  is lager than the total volume of the stator core  7  and the heat absorbing jacket  10 ,  11  so that the oil O from the heat absorbing jacket  10 ,  11  is received successfully by the tank  12 . Leg portions  13  made of heat insulation material are disposed between the housing  4  and the tank  12 . A storage chamber  12 A storing oil O is formed inside the tank  12 . The storage chamber  12 A is disposed in the housing  4  at a position corresponding to the bottom of the heat absorbing jacket  10 ,  11 . The storage chamber  12 A is open at the top thereof. The tank  12  has an outlet  12 B extending downward from bottom of the storage chamber  12 A for connection to the heat exchanger  2 . As shown in  FIG. 1 , the outlet  12 B is connected to the heat exchanger  2  through the pipe  3 A. 
         [0033]    The heat exchanger  2  functions to exchange heat between the oil O and the air as second heat medium. A pump (not shown) is disposed in each of the pipes  3 A,  3 B. 
         [0034]    In this heat recovery system for a vehicle, electric current flowing in the coil  8  of the motor  1  creates magnetic field between the stator core  7  and the rotor  9 , so the rotor  9  and hence the rotary shaft  5  are rotated. The rotary shaft  5  is operatively connected to a drive shaft of the vehicle. During the operation of the motor  1 , heat is produced in the coil  8 . 
         [0035]    When the pump (not shown) in this heat recovery system for a vehicle is started, the oil O is circulated through the heat absorbing jackets  10 ,  11 , the tank  12 , the pipes  3 B, and the heat exchanger  2 . Therefore, the oil O in the pipe  3 B is flowed into the passages  10 A,  11 A of the heat absorbing jackets  10 ,  11  via the inlets  10 B,  11 B. Referring to  FIG. 2 , the oil O stored in the passage  10 A,  11 A is in direct contact with the coil, so that the heat of the coil  8  is transferred to the oil O efficiently. Thus, the oil O absorbs and recovers heat from the coil  8  efficiently. 
         [0036]    The oil O in the passages  10 A,  11 A is stored in the heat absorbing jackets  10 ,  11  temporarily and then flowed through the outlets  10 C,  11 C into the storage chamber  12 A of the tank  12 , where the oil O is reserved, as shown in  FIG. 3 . The leg portions  13  made of heat insulation material and disposed between the housing  4  and the tank  12  prevent the heat of the oil O from being dissipated outside of the housing. 
         [0037]    Thus, the heat recovery system for a vehicle according to the above-described embodiment of the present invention can transfer the heat from the motor  1  to the heat exchanger  2  efficiently. If this system is adapted to heat the air in a vehicle by using the heat exchanger  2 , air conditioning may be provided. Furthermore, the motor  1  may be cooled efficiently, so that the motor  1  is operated with an increased efficiency. 
         [0038]    Additionally, the motor  1  may be made through improvement of an existing motor, so that the heat recovery system of the above embodiment of the invention may be made economical. 
         [0039]    Referring to  FIG. 5 , the heat recovery system according to the second embodiment of the present invention differs from that of the first embodiment in that a heat absorbing jacket  14  of a crescent-shape is used. The oil O flowing into the oil passages  10 A,  11 A through the inlets  10 B,  11 B is transferred along the coil  8  and stored in the heat absorbing jacket  14  temporarily. Other advantageous effects are the same as those of the heat recovery system according to the first embodiment. 
         [0040]    Referring to  FIG. 6 , the heat recovery system according to the third embodiment of the present invention differs from that of the second embodiment in that a heat absorbing jacket  15  having no outlet such as  10 C,  11 C is used. The rest of the structure of the heat recovery system is substantially the same as that of the heat recovery system according to the second embodiment. This system offers the same advantageous effects as heat recovery system according to the second embodiment. 
         [0041]    Referring to  FIG. 7  showing the heat recovery system according to the fourth embodiment of the present invention, the stator core  17  has a recess  17 A and the heat absorbing jacket  16  has a projection  16 A which is engaged with the recess  17 A of the stator core  17  so that the heat absorbing jacket  16  is secured to the stator core  17 . The provision of such projection  16 A and the recess  17 A helps to facilitate assembling of the motor  1 . Other advantageous effects are the same as those of the heat recovery system according to the first embodiment. 
         [0042]    Referring to  FIG. 8  showing the heat recovery system according to the fifth embodiment of the present invention, the heat absorbing jacket  18  has formed therein a seal groove  18   a . A heat resistant seal  20  is fitted in the seal groove  18   a  for sealing between the heat absorbing jacket  18  and the stator core  19 . Thus, oil O is prevented from leaking from the passage  10 A,  11 A, so that the heat of the coil  8  is transferred to the oil O efficiently. Other advantageous effects are the same as those of the heat recovery system according to the first embodiment. 
         [0043]    Referring to  FIG. 9  showing the heat recovery system according to the sixth embodiment of the present invention, a sheet-like insulator  21  is provided between the tank  12  and the housing  4 . The rest of the structure of the heat recovery system is substantially same as that of the first embodiment. This system offers the same advantageous effects as heat recovery system according to the first embodiment. 
         [0044]    Referring to  FIG. 10  showing the heat recovery system according to the seventh embodiment of the present invention, a heat insulating layer  22 A as an insulative body is provided on part of the inner surface of the housing  4  thereby to form a storage chamber  4   b . The rest of the structure of the heat recovery system is substantially the same as that according to the first embodiment. According to this embodiment, a new motor  1  can be manufactured by forming the heat insulating layer  22 A on the housing of existing motor, so that this system is economical. Other advantageous effects are the same as the heat recovery system according to the first embodiment. 
         [0045]    The heat insulating layer  22 A may be made of any suitable heat insulating or reflecting material. For example, heat reflecting coating, paint, plate, or mirror finish may be used for the heat insulating layer  22 A. 
         [0046]    Referring to  FIG. 11  showing the heat recovery system according to the eighth embodiment of the present invention, a heat insulating layer  22 B is provided as an insulative body on part of the outer peripheral surface of the housing  4 . As shown in  FIG. 11 , the oil storage chamber  4 C is formed, surrounded by the heat insulating layer  22 B. The rest of the structure of the heat recovery system is substantially the same as that according to the first embodiment. This system offers the same advantageous effects as the heat recovery system according to the seventh embodiment. 
         [0047]    Referring to  FIG. 12 , the heat recovery system according to the ninth embodiment of the present invention has a housing  23  and a second or outer housing  24  disposed so as to surround the housing  23  through an interspace  25  of air. An insulator  26  is interposed between the housing  23  and the outer housing  24 . The insulator  26  serves to maintain the interspace between the housing  23  and the outer housing  24 . The storage chamber  4 C is formed, surrounded by the housing  23 . The rest of the structure is the same as that of the heat recovery system according to the first embodiment. This system offers the same advantageous effects as heat recovery system according to the first embodiment. 
         [0048]    As shown  FIG. 13 , the coil  8  may be located to one side of the heat absorbing jacket  11 . In this case, the contact area between the oil O and the coil  8  is small, so that the oil O has difficulty in absorbing heat from the coil  8 . Referring to  FIG. 14  showing the heat recovery system according to the tenth embodiment of the present invention, the coil  8  is wound in such a way that increases the contact area between the oil O and the coil  8  keeping the same volume of the coil  8  covering in the heat absorbing jacket  11  as that shown in  FIG. 13 . 
         [0049]    Referring to  FIG. 15  showing the heat recovery system according to the eleventh embodiment of the present invention, a rubber washer  29 A as an auxiliary insulative body is provided between the housing  4  and the stator core  7 . The housing  4  and the stator core  7  are fastened together by bolts  28  (only one bolt being shown in the drawing). The rest of the structure of the heat recovery system is substantial the same as that according to the first embodiment. The system according to this eleventh embodiment prevents the heat of the coil  8  from being dissipated outside the housing  4  through the stator core  7 . Space formed by addition of the rubber washer  29 A may be used for passage of oil O. Other advantageous effects are the same as those of the heat recovery system according to the first embodiment. 
         [0050]    Referring to  FIG. 16 , the heat recovery system according to the twelfth embodiment of the present invention differs from that of the above eleventh embodiment in that a ceramic washer  298  is provided between the housing  4  and the stator core  7  instead of the rubber washer  29 A. The rest of the structure of the heat recovery system is substantially the same as according to the eleventh embodiment. This system offers the same advantageous effects as the heat recovery system according to the eleventh embodiment. 
         [0051]    According to the present invention, oil as the first heat medium may be replaced with water. Additionally, air as the second heat medium may be replaced with water. 
         [0052]    According to the present invention, the motor may be replaced with a generator. The heat recovery system of the present invention may be used for a motor, for example, of a train, an airplane. The coil of the motor may be wound in any way, including concentrated winding, wave winding, distributed winding.