Abstract:
A pneumatic engine system uses gas circulation to recycle exhausted air, so as to reduce gas consumption, save energy, protect the environment, operate for a longer duration, and slow down the attenuation of the power output thereof. The pneumatic engine system includes a pneumatic engine, a gas storage device, a transit gas storage tank, and a suction device. The pneumatic engine receives a compressed air to generate power output. The gas storage device stores the compressed gas and supplies the compressed gas to the pneumatic engine. The transit gas storage tank receives gas discharged from the pneumatic engine. The suction device extracts gas from the transit gas storage tank and transport the extracted gas to the gas storage device for recycle.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present application relates to a pneumatic power apparatus, and more particularly, to a gas engine system with air circulation. 
         [0003]    2. Related Art 
         [0004]    Invention of the internal combustion engine drove Industrial Revolution and brought flourish development in human civilization. However, the internal combustion engine using fossil fuels produces carbon dioxide after combustion. In addition to causing air pollution, the greenhouse effect and global warming, carbon dioxide has already endangered the survival of human and biological. Pneumatic engine mainly makes use of high pressure air to transforming gas into rotation power. Since its discharge is also air, there are no foul odor and no pollution. Cost is also lower than gasoline and diesel. Therefore the pneumatic engine is a good power generation choice. The use of high pressure gas of pneumatic engine is from a high pressure gas cylinder where gas is compressed. Gas consumption of pneumatic engine is in a large volume. High pressure gas cylinder to supply pneumatic engine cannot last long. This causes the power output from pneumatic engine to attenuate; and consequently, the pneumatic engine cannot continue to operate. It is thus an important topic to reduce gas consumption with the same amount of gas supply, so as to increase the operation duration of the engine and slow down the attenuation of the power output. 
       BRIEF SUMMARY 
       [0005]    A pneumatic engine system with gas circulation operable to reduce gas consumption rate is provided. The pneumatic engine system with gas circulation allows gas exhausted from the engine to be recycled to solve the problem of traditional gas supply by the high pressure gas cylinders. This system comprises a pneumatic engine, a gas storage device, a transit gas storage tank, and a suction device. The pneumatic engine accepts a compressed gas to produce power output. The gas storage device stores the compressed gas and provides it to the pneumatic engine. The transit gas storage tank retrieves a gas discharged from the pneumatic engine. The suction device extracts gas from the transit gas storage tank and delivers the extracted gas to the gas storage device. Then gas can thus be recycled. 
         [0006]    The gas storage device comprises three gas tanks The first gas tank is used to store the compressed gas and to provide the compressed gas to the pneumatic engine. The second gas tank also stores the compressed gas. The pressure in the second gas tank is less than the pressure in the first gas tank. Therefore a first booster pump located between the first and second gas tank is used to pressurize output gas from the second gas tank. The pressurized compressed gas is then delivered to the first gas tank. The third gas tank stores the compressed gas and the pressure in the third gas tank is less than the pressure in the second gas tank. A second booster pump located between the second and third gas tanks is used to pressurize gas output from the third gas tank. The pressurized gas is stored in the second gas tank. Gas discharged from the first and second booster pumps output to the transit gas tank for recycling. The suction device transports the recycled gas from the transit gas storage tank to the second and third gas tanks. 
         [0007]    In some embodiments, a pneumatic engine system may further comprise an air compressor/gas storage cylinder set. When the pressure in the third gas tank is insufficient, the air compressor/gas storage cylinder set supplements the pressure in the third gas tank. 
         [0008]    The suction device comprises a cylinder block possessing piston cylinder. The piston cylinder has an intake valve and an exhaust valve. A piston moves in the piston cylinder. A crank chamber is provided in one side of the piston cylinder. Crank member located in the crank chamber and the piston are pivotally connected together by a connecting rod. When the crank member is rotated, the piston in the piston cylinder moves up and down. A spindle structure having a right spindle and a left spindle is provided. The left spindle located in crank chamber is pivotally connected to crank members and protrudes from one side of crank chamber. The right spindle located in the crank chamber is pivotally connected to the crank member and protrudes from the other side of crank chamber. The left and right spindles rotate synchronously. An intake cam is fixed on the left spindle and an exhaust cam is fixed on the right spindle. An intake switch in the intake valve opens or closes the intake valve by means of the intake cam. An exhaust switch in the exhaust valve opens or closes the exhaust valve by means of the exhaust cam. A motor drives the spindle to rotate and makes the intake valve and the exhaust valve open or close. The spindle also drives the piston to move up and down. Gas enters into the transit gas storage tank from the intake valve and discharges from the exhaust valve through piston compression. 
         [0009]    Gas discharged from the pneumatic engine, the first booster pump, the second booster pump, and the third booster pump has residual pressure. This discharged gas will be recycled to the transit gas storage tank. The suction device is used to withdraw the gas to the second and third gas tanks The recycled residual pressure can reduce gas consumption. In addition to energy saving and environmental protection, the present application also allows the pneumatic engine to maintain a longer running time and reduce attenuation speed of power output. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]    These and other features and advantages of the various embodiments disclosed herein will be better understood with respect to the following description and drawings, in which like numbers refer to like parts throughout, and in which: 
           [0011]      FIG. 1  is a system configuration diagram for the pneumatic engine system using gas circulation; 
           [0012]      FIG. 2  is a cross-sectional view of the suction device in the pneumatic engine and displays the spindle in the initial state; 
           [0013]      FIG. 3  is a side view of  FIG. 2 ; 
           [0014]      FIG. 4  is another side view of  FIG. 2 ; 
           [0015]      FIG. 5  is a cross-sectional view of the suction device in the pneumatic engine and displays the spindle rotating 30 degree; 
           [0016]      FIG. 6  is a side view of  FIG. 5 ; 
           [0017]      FIG. 7  is another side view of  FIG. 5 ; 
           [0018]      FIG. 8  is a cross-sectional view of the suction device in the pneumatic engine and displays the spindle rotating 193.5 degree; 
           [0019]      FIG. 9  is a side view of  FIG. 8 ; 
           [0020]      FIG. 10  is another side view of  FIG. 8 ; 
           [0021]      FIG. 11  is a cross-sectional view of the suction device in the pneumatic engine and also shows the idler and pulley; 
           [0022]      FIG. 12  is a cross-sectional view displaying the pneumatic engine and motor; 
           [0023]      FIG. 13  is a relational diagram showing rotation angles of the spindle, intake valve and exhaust valve in the pneumatic engine. 
       
    
    
     DETAILED DESCRIPTION 
       [0024]    Referring to  FIG. 1 , a pneumatic engine system with gas circulation  100  including the pneumatic engine  10 , the gas storage device  20 , the transit gas storage tank  30  and the suction device  40  is provided. 
         [0025]    The pneumatic engine  10  accepts compressed gas to produce power output. This is a way to convert compression energy of gas into kinetic energy. The pneumatic engine used in this embodiment is a power apparatus such as U.S. Pat. No. 7,866,251B2 (corresponding case including PCT/CN2007/001994, CN665571, and TWI327621, which are incorporated by reference by its entirety). The gas storage device  20  can store the compressed gas and provide it to the pneumatic engine  10 . The gas storage device  20  in this embodiment includes the first gas tank  21 , the second gas tank  22 , the first booster pump  23 , the third gas tank  24  and the second booster pump  25 . The first gas tank  21  stores the compressed gas and supplies it to the pneumatic engine  10 . The second gas tank  22  also stores the compressed gas. The pressure in the second tank  22  is less than the pressure in the first gas tank  21 . Therefore, the first booster pump  23  located between the first gas tank  21  and the second gas tank  22  is used to pressurize output gas from the second gas tank  22 . The pressurized compressed gas is then delivered to the first gas tank  21 . There are two first booster pumps  23  used in this embodiment. The third gas tank  24  stores compressed gas and the pressure in this tank is less than the pressure in the second gas tank  22 . The second booster pump  25  located between the second gas tank  22  and the third gas tank  24  is used to pressurize gas output from the third gas tank  24 . The pressurized gas is stored in the second gas tank  22 . 
         [0026]    In  FIG. 1 , the gas storage device  20  includes a high pressure gas supplement tank  26 , the third booster pump  29  and a regulator valve  31 . The high pressure gas supplement tank  26  is for the storage of compressed gas and the pressure is greater than the pressure in the first gas tank  21 . When pressure in the first gas tank is below the set value, the regulator valve  31  is opened. The high pressure gas supplement tank  26  replenishes pressurized gas to the first gas tank  21 . The regulator valve  31  is closed to stop supplying gas until the pressure in the first gas tank  21  is higher than the set value. The third booster pump  29  located between high pressure supplement tank  26  and the third gas tank  24  is used to pressurize output gas from the third gas tank  24 . The pressurized compressed gas is then delivered to the high pressure supplement tank  26 . 
         [0027]    As described above, gas discharged from the pneumatic engine  10 , the first booster pump  23 , the second booster pump  25  and the third booster pump  29  still has residual pressure. The transit gas storage tank  30  is used to retrieve gas discharged. The suction device  40  is used to withdraw gas discharged to the second gas tank  22  and/or the third gas tank  24  in the gas storage device  20 . The recycled residual pressure can reduce gas consumption. In addition to energy saving and environmental protection, the present application also allow the pneumatic engine to maintain a longer running time and reduce attenuation speed of power output. 
         [0028]    The check valve  71 ,  72 ,  73  are installed in the first booster pump  23 , the second booster pump  25  and the transit gas storage tank  30 , respectively. The check valve  74  and  75  are installed between the suction device  40 , the second gas tank  22 , and the third gas tank  24 . The check valve  76  is installed between the first gas tank  21  and the pneumatic engine. The check valve  78  is installed between the second gas tank  22  and the first booster pump  23  and the check valve  77  is located between the high pressure gas supplement tank  26  and the first gas tank  21 . The check valves are operable to avoid gas reversing. 
         [0029]    Referring to  FIGS. 2 to 12 , the suction device  40  in this embodiment includes a cylinder block  41 , a piston  42 , a crank chamber  43 , a crank member  44 , a spindle  45 , an intake cam  46 , an exhaust cam  47 , an intake switch  48 , an exhaust switch  49  and a motor  50 . 
         [0030]    The cylinder block  41  includes the piston cylinder  411 , which has the intake valve  412  and the exhaust valve  413 . The piston  42  is located and operable to move in the piston cylinder  411 . The crank chamber  43  is provided at one side of the piston cylinder  411 . In this embodiment, the crank chamber is located on the bottom side. The crank member  44  is disposed in crank chamber  43 . The crank member  44  has a connecting rod  441 . The crank member  44  and the piston  42  are pivotally connected together by the connecting rod  441 . When the crank member  44  is rotated, the piston  42  in the piston cylinder  411  moves up and down. In this embodiment, the spindle  45  having a left spindle  451  and a right spindle  452  is provided. The left spindle  451  located in the crank chamber  43  is pivotally connected to the crank member  44  and protrudes from one side of crank chamber  43 . The right spindle  452  located in the crank chamber  43  is pivotally connected to the crank member  44  and protrudes from the other side of crank chamber  43 . The left spindle and right spindle rotates synchronously. The intake cam  46  is fixed on the left spindle  451  and the exhaust cam  47  is fixed on the right spindle  452 . In addition, the intake switch  48  located in the intake valve  412  opens or closes the intake valve  412  by means of the intake cam  46 . The exhaust switch  49  located in the exhaust valve  413  opens or closes the exhaust valve  413  by means of the exhaust cam  47 . 
         [0031]    The Motor  50  drives the spindle  45  to rotate and makes the intake valve  412  and the exhaust valve  413  open or close. The spindle  45  also drives the piston  42  to move up and down. Gas enters into the transit gas storage tank  30  from the intake valve  412  and discharges from the exhaust valve  413  through the piston  42  compression. In the embodiment as shown in  FIGS. 11 and 12 , rotation of the right spindle  452  in the spindle  45  is driven by the motor  50  through the belt  51  and the pulley  52 . In addition, the left spindle  451  has the idler  53 . The moment of inertia from the idler  53  assists the operation of the suction device  40 . 
         [0032]    Referring to  FIG. 13 , the piston  42  as shown in  FIGS. 2-4  is at the highest point for the beginning of a cycle. The intake valve  412  and the exhaust valve  413  are in the close state. When the spindle  45  rotates to about 4°, the intake valve  412  starts to open and the exhaust valve  413  is still in the closed state. Referring to  FIGS. 5 to 7 , when the spindle  45  rotates to about 30°, the intake valve  412  is fully open and the exhaust valve is still in the closed state. While the piston  42  goes down, gas enters into the piston cylinder  411 . When the spindle  45  rotates to about 149°, the intake valve  412  starts to close and the exhaust valve still remains in the closed state. When the spindle  45  rotates to about 176°, the intake valve  412  is fully closed and the exhaust valve  413  is still in the closed state. When the spindle  45  rotates to about 180.5°, the exhaust valve  413  starts to open and the intake valve  412  is closed. The piston  42  starts to rise and gas is then pushed out. Referring to  FIGS. 8 to 10 , when the spindle  45  rotates to about 193.5°, the exhaust valve  413  is fully open and the intake valve  412  is closed. When the spindle  45  rotates to about 346.5°, the exhaust valve  413  starts to close and the intake valve  412  is still in the closed state. When the spindle  45  rotates to about 359°, both the intake valve  412  and the exhaust valve  413  are closed. When the piston  42  reaches the highest point, gas in the piston cylinder  42  is pushed out completely. When the spindle  45  rotates to about 360°, both the intake valve  412  and the exhaust valve  413  are closed. A full cycle of piston  42  has been completed. Gas in the transit gas storage tank  30  can be effectively pumped into the second gas storage tank  22  and the third gas storage tank  24  by the suction device  40 . 
         [0033]    This embodiment further comprises an air compressor/gas storage cylinder set  80 . When the third gas tank  24  is insufficient pressure, the air compressor/gas storage cylinder set  80  supplements the pressure in the third gas tank  24 . 
         [0034]    In  FIG. 1 , a switch valve  27  is provided to a pipeline  28  which is used to connect the first gas tank  21 , the second gas tank  22  and the third gas tank  24 . The switch valve  27  can open and close the external path and can also be conveniently inflated in advance for the first gas tank  21 , the second gas tank  22  and the third gas tank  24 . 
         [0035]    Operation instructions for this embodiment are as follows. Firstly, the high pressure gas supplementary tank  26 , the first gas tank  21 , the second gas tank  22  and the third gas tank  24  are filled with sufficient gas. In this embodiment, the pressure in the high pressure gas supplementary tank  26  should be maintained between about 25 kg/cm 2  and about 40 kg/cm 2 . The pressure in the first gas tank  21  is at about 16 kg/cm 2 . The pressure of the second gas tank  22  is at about 8 kg/cm 2 . The pressure of the third gas tank  24  is at about 6 kg/cm 2 . When the pneumatic engine  10  opens, the first gas tank  21  starts to supply gas. Gas discharged from the pneumatic engine  10  is recycled by he the transit gas storage tank  30  and the suction device  40  withdraws gas discharged to the second gas tank  22  or/and the gas tank  24  for recycling. After the second booster pump  25  pressurizes the gas from the third gas tank  24 , the pressurized gas is then sent to the second gas tank  22 . After the first booster pump  23  pressurizes gas discharged from the second gas tank  22 , the pressurized gas discharged is sent to the first gas tank for recycling. When the press of the first gas tank  21  is insufficient, the high pressure gas supplementary tank  26  is responsible for replenishing. Gas discharged in the first booster pump  23 , the second booster pump  25  and the third booster pump is all sent to the transit gas storage tank  30  to complete a recycling loop. Of course, the air compressor/gas storage cylinder set  80  should replenish gas if any gas consumption is happened during this time period. Therefore this embodiment attenuates gas consumption to a minimum level by using recycling gas. 
         [0036]    The above description is given by way of example, and not limitation. Given the above disclosure, one skilled in the art could devise variations that are within the scope and spirit of the invention disclosed herein, including configurations ways of the recessed portions and materials and/or designs of the attaching structures. Further, the various features of the embodiments disclosed herein can be used alone, or in varying combinations with each other and are not intended to be limited to the specific combination described herein. Thus, the scope of the claims is not to be limited by the illustrated embodiments.