Patent Publication Number: US-2007122288-A1

Title: Pressurizing water pump with control valve device

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a pressurizing water pump. More particularly, the present invention relates to a pressurizing water pump with a control valve device for pumping water to a faucet in a building or into a storage tank mounted on top of the building.  
      2. Description of the Related Art  
      It is well known to use a pressurizing water pump for pumping water to a faucet in a building or into a storage tank mounted on top of the building. A typical pressurizing water pump (or simply “pump”) includes an accumulator and a pressure switch to control operation of the pump. When a faucet in the building is turned on, the water pressure in the piping drops and water is supplied from the accumulator to the faucet, which causes a pressure drop of the accumulator. When the water pressure in the accumulator is below a predetermined value, the pressure switch is activated to start the pump. Water is supplied to the faucet and the accumulator at the same time. The pressure switch is activated to turn off the pump when the water pressure in the accumulator reaches another predetermined value. In practice, the pump is repetitiously turned on and off due to the various periods of times and various amounts of water output via the faucet, resulting in unstable output of water, which causes problems to a user taking a hot water bath. The temperature and pressure of the output water are unstable. Gas leakage is liable to occur. The elements of the pump are apt to be damaged and the life of the pump is shortened. Further, the momentary voltage is unstable and the electricity consumption is increased.  
     SUMMARY OF THE INVENTION  
      A water pressurizing pump in accordance with the present invention comprises an accumulator, a control valve device, a valve device, a pressure switch, and a motor.  
      The control valve device comprises a valve body including a first side and a second side. The second side of the valve body comprises a compartment. A cap is mounted in the compartment and includes a hole through which water is output to a piping system to which the water pressurizing pump is connected. At least one channel is defined in an end of a circumferential wall delimiting the compartment of the valve body and in communication with the hole of the cap. The valve body further comprises a three-way channel including a first port in communication with the accumulator, a second port, and a third port in communication with the compartment.  
      The valve device is movably mounted in the compartment of the valve body. The valve device comprises a hollow body having an end wall and an open end. The valve device further comprises a movable block mounted in the body, an elastic element mounted in the body, and an end cap for closing the open end of the body. The movable block comprises a plurality of annularly spaced legs, defining a plurality of passageways between the legs. The end wall of the body faces the end cap and includes a through-hole in communication with the channels of the valve body. The body further includes at least one outer water passageway in a circumference thereof. The end cap includes at least one hole. The elastic element is mounted between the end cap and the movable block.  
      The pressure switch is coupled to the first side of the valve body and in communication with the second port of the three-way channel of the valve body. The motor includes an outlet. The outlet of the motor, the hole of the cap, and the piping system are in communication with one another.  
      When the piping system is open and a water pressure in the accumulator is above a first value, water flows from the accumulator into the piping system via the three-way channel and pushes the valve device toward the cap. The water enters the piping system via the at least one outer water passageway of the body of the valve device, the at least one channel of the valve body and the outlet of the cap.  
      When the piping system is open and the water pressure in the accumulator is below the first value, the motor is turned on to pump water to the piping system and the outlet of the cap. The water flowing to the outlet of the cap enters the at least one channel of the valve body and pushes the valve device away from the cap, with the movable block blocking the hole of the body of the valve device, not allowing water to enter the accumulator, thereby maintaining the water pressure in the accumulator in a stable low-pressure state.  
      When the piping system is closed and the water pressure in the accumulator is below the first value, the motor is turned on to pump water to the outlet of the cap. The water flowing to the outlet of the cap enters the at least one channel of the valve body, pushes the valve device away from the cap and compresses the elastic element, moving the movable block away from the end wall of the body of the valve device, allowing water from the inlet of the cap to flow into the accumulator via the at least one channel of the valve body, the through-hole of the end wall of the body, the passageways between the legs of the movable block, the at least one hole of the end cap, and the three-way channel until the water pressure in the accumulator is greater than a second value.  
      Preferably, the valve device further comprises a muffling element mounted between the movable block and the end wall of the body of the valve device.  
      Preferably, the end wall of the body of the valve device further comprises at least one protrusion abutting against the cap to provide a water-flowable gap between the body of the valve device and the cap.  
      Preferably, the valve device further comprises a seal member between the end cap and an end wall delimiting the compartment of the valve body. The seal member includes a hole through which water is flowable.  
      Preferably, the accumulator comprises a first housing and a second housing that together define a groove therebetween. A membrane is mounted in the accumulator and separates the accumulator into an air chamber and a water chamber. The membrane comprises a base including a circumferential wall that is fittingly received in the groove. The membrane, the first housing, and the second housing are fixed together by supersonic welding or screws to increase pressure-resisting capacity of the membrane and the accumulator.  
      The cap may be made of plastic and fixed in the compartment of the valve body of the control valve device by supersonic welding.  
      Other objectives, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a side elevational view of a pressurizing water pump in accordance with the present invention.  
       FIG. 2  is an exploded perspective view of a control valve device of the pressurizing water pump in accordance with the present invention.  
       FIG. 3  is a side view, partially sectioned, of an accumulator and the control valve device of the pressurizing water pump in accordance with the present invention.  
       FIG. 4  is a sectional view illustrating pressure release operation of the control valve device.  
       FIG. 5  is a sectional view similar to  FIG. 4 , illustrating pressostatic output operation of the control valve device.  
       FIG. 6  is a sectional view similar to  FIG. 5 , illustrating pressure-accumulating operation of the control valve device.  
       FIG. 7  is an exploded perspective view of the accumulator and a membrane of the pressurizing water pump in accordance with the present invention.  
       FIG. 8 a  sectional view showing coupling of the accumulator and the membrane of the pressurizing water pump in accordance with the present invention.  
       FIG. 9  is a sectional view of the membrane in  FIG. 7 .  
       FIG. 10  is an enlarged sectional view of a portion in  FIG. 8 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Referring to  FIG. 1 , a pressurizing water pump  1  in accordance with the present invention comprises an accumulator  12 , a control valve device mounted below the accumulator  12 , a pressure switch  14 , and a motor  15 . The accumulator  12  includes a hole  122  for filling gas (such as air) into the accumulator  12 , which is conventional. The pressure switch  14  is coupled to a first side of a valve body  11  of the control valve device.  
      Referring to  FIGS. 2 and 3 , a compartment  113  is defined in a second side of the valve body  11  of the control valve device. Mounted in the compartment  113  are a valve device  13  and a cap  16 . The cap  16  includes a hole  161  through which water is output. The valve device  13  is movable in the compartment  113 . The valve body  11  further comprises a three-way channel  111  including a first port in communication with the accumulator  12 , a second port in communication with the pressure switch  14 , and a third port in communication with the compartment  113  via a passageway  112  in the valve body  11 .  
      At least one channels  1131  is defined in an end of a circumferential wall delimiting the compartment  113  of the valve body  11  and in communication with the hole  161  of the cap  16 . In this example, a plurality of annularly spaced channels  1131  are provided, with an end of each channel  1131  distal to the cap  16  tapering toward the first side of the valve body  11  to provide a water concentrating effect.  
      Still referring to  FIGS. 2 and 3 , the valve device  13  comprises a body  131 , a movable block  132 , an elastic element  133 , and an end cap  134 . The body  131  is substantially a hollow cylinder with an end wall  1315  having a through-hole  1311 . At least one water passageway (several channels  1312  and several grooves  1313  in this example) is defined along a circumference of the body  131  to provide water passageways. A plurality of annularly spaced protrusions  1314  are formed on the end wall  1315  of the body  131  and abut against the cap  16  so that a water-flowable gap exists between the body  131  and the cap  16 . A muffling element  135  made of rubber or the like is mounted between the movable block  132  and the end wall  1315  of the body  131  of the valve device  13 . The muffling element  135  includes a hole (not labeled) through which water is flowable.  
      The muffling element  135 , the movable block  132 , and the elastic element  133  are mounted in the body  131 , with the movable block  132  covering the through-hole  1311  of the body  131 . The end cap  134  is mounted to close an open end of the body  131  and includes a stud  1341 . A seal member (such as a rubber ring)  136  is mounted between the end cap  134  and an end wall delimiting the compartment  131  of the valve body  11 . The seal member  136  includes a hole (not labeled) allowing water to flow therethrough.  
      The elastic element  133  includes a first end mounted around the stud  1341  of the end cap  134  and a second end mounted around a peg  1321  on the movable block  132 . The elastic coefficient of the elastic element  133  decides the pressure threshold for pressostatic operation, which will be described later.  
      The movable block  132  further includes a plurality of annularly spaced legs  1322  projecting therefrom, delimiting a plurality of water passageways between the legs  1322 . The end cap  134  further includes at least one water-flowable hole  1342  (several holes  1342  in this example) surrounding the peg  1341 .  
      Referring to  FIG. 4 , when a piping system to which the pressurizing water pump is connected is open (e.g., a faucet in a building is turned on), the water in the accumulator  12  enters the compartment  113  of the valve body  11  of the control valve device via the three-way channel  111  and the passageway  112  of the valve body  11 . The valve device  13  is pushed toward the cap  16  and water flows through the channels  1312  and the grooves  1313  (the outer water passageways) of the body  131  of the valve device  13 , the channels  1131  of the valve body  11 , and the outlet  161  of the cap  16  into the piping system, providing water to the faucet. It is noted that the movable block  135  blocks the hole  1311  of the body  131  of the valve device  13  under the action of the elastic element  133 .  
      The flow of water continues until a water pressure in the accumulator  12  is smaller than a predetermined value. At this time, the pressure switch  14  is activated to turn on the motor  15 . The motor  15  has an outlet. The outlet of the motor  15 , the hole  161  of the cap  16 , and the piping system are in communication with one another via a three-way pipe or the like, which is conventional.  
      Referring to  FIG. 5 , when the water pressure in the accumulator  12  is smaller than the predetermined value, water is pumped by the motor  15  to the outlet  161  of the cap  16  and the faucet. Water flowing to the outlet  161  of the cap  16  enters the compartment  113  and pushes the valve device  13  away from the cap  16  until the channels  1312  and the grooves  1313  (the outer water passageways) of the body  131  of the valve device  13  are blocked. The movable block  135  blocks the hole  1311  of the body  131  of the valve device  13  under the action of the elastic element  133 , for the water pressure is insufficient to overcome the elastic element  133 . Thus, the valve body  11  does not allow water to enter the accumulator  12 . Hence, the accumulator  12  is in a stable preset low-pressure state, i.e., the accumulator  12  is pressostatic. The motor  15  is in an on state under the control of the pressure switch  14  and outputs water to the faucet. The output of water via the faucet is stable, as water could not enter the accumulator  12 . It is noted that elastic element  133  is not compressed during the pressostatic water supply to the faucet.  
      When the faucet is turned off, the water pressure in the piping system increases. As illustrated in  FIG. 6 , water is pumped by the pump to enter the compartment  113  via the outlet  161  of the cap  16 , and the water pressure is high enough to compress the elastic element  133  while moving the movable block  132  of the valve device  13  away from the cap  16 . The motor  15  is still running when the faucet is closed. Water flows through the through-hole  1311  of the body  131  of the valve device  13 , the passageways between the legs  1322  of the movable block  132 , the holes  1342  of the end cap  134 , the passageway  112  of the valve body  11 , and the three-way channel  111  and then into the accumulator  12  until the water pressure in the accumulator  12  reaches another predetermined value. The pressure switch  14  is then activated to turn off the motor  15 .  
      In an example of the invention, the cap  16  is made of plastic and fixed in the compartment  113  of the valve body  11  of the control valve device by supersonic welding. This provides improved structural strength. Thus, the control valve device could withstand higher water pressure.  
       FIGS. 7 through 10  show coupling between a membrane  121 , and a first housing  124  and a second housing  125  constituting the accumulator  12 . The membrane  12  is substantially U-shaped in section and comprises a base  128  including a circumferential wall  120  that is fittingly received in a correspondingly formed groove  123  defined between the first housing  124  and the second housing  125  of the accumulator  12 . The membrane  121  separates the accumulator  12  into a water chamber  126  that is in communication with the first port of the three-way channel  111  and an air chamber  127  that is filled with air via the hole  122 . The functions of the water chamber  126  and the air chamber  127  are conventional. The base  128  with a circumferential wall  120 , the first housing  124  and the second housing  125  are then fixed together by supersonic welding or screws. This increases the pressure-resisting capacity of the membrane  121  and the accumulator  12 . More specifically, the membrane  121  and the accumulator  12  could withstand a water pressure up to 12 kg while conventional designs using screws or bolts/nuts for fixing the membrane  121  and the accumulator  12  could only withstand a water pressure of about 6 kg. The stable output effect of the pressurizing water pump is improved. Further, the arrangement of the base  128  with a circumferential wall  120  and the annular groove  123  defined by the first and second housings  124  and  125  provides an improved sealing effect such that leakage of water would not occur.  
      Although a specific embodiment has been illustrated and described, numerous modifications and variations are still possible without departing from the essence of the invention. The scope of the invention is limited by the accompanying claims.