Abstract:
A compressor pressure measuring device drives a compressor to operate for measuring its pressure. A positive pressure pipeline and a negative pressure pipeline are connected to the entry end and the exit end of the compressor, respectively. The positive pressure pipeline and the negative pressure pipeline are provided with an electromagnetic valve, respectively. A control module controls the operation of the compressor and the on/off of the electromagnetic valves in the positive pressure pipeline and the negative pressure pipeline. This automatically detects positive pressure and negative pressure of the compressor.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of Invention 
         [0002]    The invention relates to a compressor pressure measuring device and, in particular, to a compressor pressure measuring device that automatically detects positive pressure and negative pressure of the compressor. 
         [0003]    2. Related Art 
         [0004]    Normally, after a compressor is assembled, one has to perform a positive and negative pressure test in order to determine whether the output pressure thereof reaches the predetermined value and to determine whether there is any internal leakage. 
         [0005]    As shown in  FIG. 8 , the conventional compressor testing method first puts the compressor  81  to be tested on a working platform  82 . The transmission axle of the compressor  81  has a belt wheel  84  driven by a motor  83 . This drives the compressor  81  for a test run. To test the positive pressure, one end of a positive pressure pipeline  85  is connected to the output end  811  of the compressor  81 . The input end of the compressor  81  is injected with an appropriate test fluid. One then starts the motor  83  to perform the test run for the compressor  81 . In this case, a switch  86  is toggled to close the other end of the positive pressure pipeline  85 . One can then read the output positive pressure of the compressor  81  from the gauge  851  on the positive pressure pipeline  85 . After the positive pressure test, one manually toggle the switch  86  so that the test fluid in the positive pressure pipeline  85  flows from the other end of the positive pressure pipeline  85  into a recycle bucket (not shown). 
         [0006]    To perform the negative pressure test, as shown in  FIG. 9 , one end of a negative pipeline  87  is connected to the input end  812  of the compressor  11 . One then starts the motor  83  to drive the compressor  81  for a test run. Another switch  88  in the negative pressure pipeline  87  is toggled so that the other end thereof is closed. The switch  86  of the positive pressure pipeline  85  is toggled on. One can then read the negative pressure on the input end  812  of the compressor  81  from the gauge  871  on the negative pressure pipeline  87 . This value is used to determine whether there is any internal leakage in the compressor. 
         [0007]    However, the above-mentioned conventional compressor testing method is completely manual, including the assembly of the belt wheel  84 , the toggles of the switches  86 ,  88 , and the judgments based on the pressure values. Not only is the entire testing procedure too time- and manpower-consuming, it is also likely to involve human errors. 
       SUMMARY OF THE INVENTION 
       [0008]    An objective of the invention is to provide a compressor pressure measuring device that can automatically test the positive and negative pressure of the compressor, effectively saving manpower costs and shortening test time. 
         [0009]    Another objective of the invention is to provide a compressor pressure measuring device that automatically determines whether the measured pressure value is normal, thereby increasing the accuracy in compressor tests. 
         [0010]    To achieve the above-mentioned objectives, the compressor pressure measuring device connects to the entry end and exit end of a compressor. It drives the transmission axle of the compressor to run for a pressure test. The disclosed compressor pressure measuring device includes: a platform, a tool, a positive pressure pipeline, a negative pressure pipeline, and a control module. 
         [0011]    The platform has a holder for holding a compressor. The tool has an inner tooth hole for the insertion and connection of the transmission axle of the compressor. The tool is driven by a motor so that the connected compressor can be driven to run. 
         [0012]    One end of the positive pressure pipeline has a connector corresponding to the exit end of the compressor. The other end thereof connects to a recycle bucket. The positive pressure pipeline has a first electromagnetic (EM) valve for controlling its connection state. A positive pressure test area is formed between the first quick-release connector and the first EM valve in the positive pressure pipeline. A positive pressure gauge is disposed in the positive pressure test area. 
         [0013]    One end of the negative pressure pipeline has another connector corresponding to the entry end of the compressor. The other end thereof connects to a test fluid container. The negative pressure pipeline has a second EM valve for controlling whether the test fluid container or external air is in fluid communications with the negative pressure pipeline. A negative pressure test area is formed between the quick-release connector and the second EM valve in the negative pressure pipeline. A negative pressure gauge is disposed in the negative pressure test area. 
         [0014]    The control module has several indicators electrically connected with the motor, the first EM valve, the second EM valve, and the positive and negative pressure gauges for controlling the on/off of the motor, the first EM valve, and the second EM valve. This enables the invention to automatically test the positive pressure or negative pressure of the compressor. The control module has default positive and negative pressure values. The control module compares the values measured by the positive and negative pressure gauges with the default positive and negative pressure values, and uses the indicators thereon to show the comparison result. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    These and other features, aspects and advantages of the invention will become apparent by reference to the following description and accompanying drawings which are given by way of illustration only, and thus are not limitative of the invention, and wherein: 
           [0016]      FIG. 1  is a schematic view of the structure of the invention; 
           [0017]      FIG. 2  shows the usage of the invention; 
           [0018]      FIG. 3  is a schematic view showing the disclosed tool and the transmission axle of a compressor are connected; 
           [0019]      FIG. 4  is a schematic view showing the connection between the positive and negative pressure pipelines and the transmission axle of the compressor; 
           [0020]      FIG. 5  is a schematic view of flowing path for the positive pressure test; 
           [0021]      FIG. 6  is a schematic view of flowing path when the positive pressure test is over; 
           [0022]      FIG. 7  is a schematic view of flowing path for the negative pressure test; 
           [0023]      FIG. 8  is a schematic view of a positive pressure test using a conventional compressor pressure measuring device; and 
           [0024]      FIG. 9  is a schematic view of a negative pressure test using a conventional compressor pressure measuring device. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements. 
         [0026]    Please refer to  FIGS. 1 to 3 . The disclosed compressor pressure measuring device  10  connects to the entry end  61  and the exit end  62  of a compressor  60 . It can drive the transmission axle  63  of the compressor  60  to perform a pressure test. The compressor pressure measuring device  10  includes: a platform  11 , a tool  21 , a positive pressure pipeline  31 , a negative pipeline  41 , and a control module  51 . 
         [0027]    The platform  11  has a holder  12  for holding the compressor  60 . The holder  12  has an elevating mechanism  13 . In this embodiment, the elevating mechanism  13  has a sliding rail  131  vertically extending toward the platform  11 . The holder  12  is installed on the sliding rail  131  of the elevating mechanism  13  to slide up and downs along the sliding rail  131 . 
         [0028]    The tool  21  has an inner tooth hole  22  for the insertion and connection of the transmission axle  63  of the compressor  60 . The tool  21  is driven by a motor  23  to concurrently drive the connected compressor  60  for a test run. 
         [0029]    The positive pressure pipeline  31  consists of a flexible soft pipe. Its one end has a first quick-release connector  32  corresponding to the exit end  62  of the compressor  60 . The other end of the positive pressure pipeline  31  connects to a recycle bucket  33 . The positive pressure pipeline  31  has a first EM valve  34  for controlling its connection state. A positive pressure test area  35  is formed between the first quick-release connector  32  and the first EM valve  34  in the positive pressure pipeline  31 . A positive pressure gauge  36  is disposed in the positive pressure test area  35 . 
         [0030]    One end of the negative pressure pipeline  41  has a second quick-release connector  42  corresponding to the entry end  61  of the compressor  60 . The other end of the negative pressure pipeline  41  connects to a test fluid container  43 . The negative pressure pipeline  41  has a second EM valve  44  for controlling whether the test fluid container  43  or external air is in fluid communications with the negative pressure pipeline  41 . A negative pressure test area  45  is formed between the second quick-release connector  42  and the second EM valve  44  in the negative pressure pipeline  41 . A negative pressure gauge  46  is disposed in the negative pressure test area  41 . 
         [0031]    The control module  51  has several indicators  52  electrically connected with the motor  23 , the first EM valve  34 , the second EM valve  44 , and the positive and negative pressure gauges  36 ,  46  for controlling the on/off of the motor  23 , the first EM valve  34 , and the second EM valve  44 . This enables the invention to automatically test the positive pressure or negative pressure of the compressor  60 . The control module  51  has default positive and negative pressure values. The control module  51  compares the values measured by the positive and negative pressure gauges  36 ,  46  with the default positive and negative pressure values, and uses the indicators  52  on the control module  51  to show the comparison result. 
         [0032]    To further elucidate the features in the disclosed structure, the technical means of the invention, and the achieved effects, the usage of the invention is described below: 
         [0033]    Before automatically testing the positive and negative pressures of the compressor, the invention first sets the positive and negative pressure values in the control module  51 . In this embodiment, the positive pressure value is set at 200 psi, and the negative pressure value is set between 760 and 435 mmHG. As shown in  FIG. 3 , the compressor  60  to be tested is put in the holder  12  of the platform  11 . The transmission axle  63  of the compressor  60  aligns with the inner tooth hole  22  of the tool  21 . The user can change the tool  21  according to the size and specifications of the compressor  60 . The elevating mechanism  13  is used to adjust the position of the compressor  60  and then fastened. Afterwards, as shown in  FIG. 4 , the positive and negative pressure pipelines  31 ,  41  are connected to the entry end  61  and the exit end  62  of the compressor  60 . This finishes the preparation for positive and negative pressure tests of the compressor. 
         [0034]    When the motor  23  is started to drive the tool  21  and the connected compressor  60  for a positive pressure test, as shown in  FIG. 5 , the control module  51  closes the first EM valve  34 . The second control valve  44  is open to connect with the test fluid container  43 . In this case, the test fluid in the test fluid container  43  flows into the compressor  60 . Through the action of the compressor  60 , the test fluid enters the positive pressure test area  35  in the positive pressure pipeline  31  via the exit end  62 . When the positive pressure gauge  36  of the positive pressure test area  35  reaches 200 psi, the control module  51  automatically determines that the positive pressure is normal and outputs a control signal for the corresponding indicator  52  thereon to light up. If the positive pressure gauge  36  does not reach 200 psi, the control module  51  automatically determines that the positive pressure is abnormal and outputs another control signal to light up the corresponding indicator  52 . After testing the positive pressure of the compressor, as shown in  FIG. 6 , the control module  51  stops the operation of the motor  23  and opens the first EM valve  34 . The second control valve  44  closes the test fluid container  43 . The test fluid in the positive pressure test area  35  can thus flow into the recycle bucket  33  via the other end of the positive pressure pipeline  31 . 
         [0035]    When the motor  23  is started to drive the tool  21  and the connected compressor  60  for a negative pressure test, as shown in  FIG. 7 , the control module  51  opens the first EM valve  34 . The second control valve  44  closes the test fluid container  43 . If the value measured by the negative pressure gauge  46  is between 760 and 435 mmHG and the negative pressure does not drop within a predetermined time, then the control module  51  automatically determines that the negative pressure is normal and outputs a control signal to light up the indicator  52  thereon. If the value measured by the negative pressure gauge  46  is not between 760 and 435 mmHG or the negative pressure is detected to drop within a predetermined time, the control module  51  automatically determines that the negative pressure is abnormal and outputs another control signal to light up the corresponding indicator  52 . 
         [0036]    According to the above description, the invention has the following advantages: 
         [0037]    1. During the installation of a compressor  60  onto the invention, the user only needs to align the transmission axle  63  of the compressor  60  with the inner tooth hole  22  of the tool  21 . The holder  12  then fixes the position thereof. With the quick-release connectors  32 ,  42  of the positive and negative pressure pipelines  31 ,  41 , the entry end  61  and the exit end  62  of the compressor  60  can be quickly connected. Therefore, it is fairly simple and quick to install the compressor  60 . 
         [0038]    2. The disclosed compressor pressure measuring device  10  can replace the tool  21  according to the size and specifications of the compressor  60 . The position of the compressor  60  is adjusted by the elevating mechanism  13  for the connection to the inner tooth hole  22  of the tool  12 . Therefore, the disclosed compressor pressure measuring device  10  can be used for pressure tests on compressors of all specifications. 
         [0039]    3. The compressor pressure measuring device  10  has default positive and negative pressure values in the control module  51 . The control module  51  automatically compares the values measured by the positive and negative pressure gauges with the default positive and negative pressure values, and uses the indicators  52  thereon to show the comparison result. The user can quickly know the pressure test result. This prevents possible human errors and thus greatly increases the accuracy of the compressor test tasks. 
         [0040]    4. The compressor pressure measuring device  10  can automatically test the positive and negative pressures of the compressor  60 . This saves the cost for manpower and effectively shortens the testing time. 
         [0041]    Although the invention has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternative embodiments, will be apparent to people skilled in the art. Therefore, it is contemplated that the appended claims will cover all modifications that fall within the true scope of the invention.