• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    A valve device included in a system for measuring differential pressure in a discharge system and wherein the valve device comprises a valve housing with an inlet and an outlet for connection to the discharge system, channels for communication with a differential pressure sensor for recording the differential pressure, a cavity comprising a calibration cone and an intermediate cavity. a position for zero point calibration / flushing of the valve device where the calibration cone separates the differential pressure sensor from the ids uid system in cases where the measuring position of the device is not present.
    公开号:SE1000682A1
    申请号:SE1000682
    申请日:2010-06-28
    公开日:2011-12-29
    发明作者:Daniel Jilderos
    申请人:Tour & Andersson Ab；
    IPC主号:
    专利说明:

    There are also constructions which solve the problem of zero point calibration and flushing of the valve device by manual procedure. An example of such a solution fi is given by GB 2 410 332 A where, where a manually controllable valve (3 0.40) connects the two pressure sides fl inadvertently and thus the system is flushed through and zero point calibrated. The same solution also contains two safety valves for protection against impermissible differential pressure levels.
    The problem with previous solutions, for example the solution described by GB 2 410 332 A, is that in the case of zero point calibration of the differential pressure sensor, the high and low pressure side fl are interconnected, which means that the zero point becomes dependent on the flow velocity through the valve device and the pressure drop. which results in an error occurring during calibration.
    Disclosure of the Invention The object of the present invention is to solve the problem of excessive interconnection of the high and low pressure side during zero point calibration and this is made possible by arranging both differential pressure sensors of the differential pressure sensor so that they do not have contact with the flowing. er measuring pages from fl uiden. This position constitutes the starting position of the device. This achieves the advantage that the calibration error is eliminated.
    According to a preferred embodiment, a flushing furildion is obtained, in order to get rid of any air remaining in the complete valve device, in cases where the measuring position of the device is not present, i.e. in its initial position, by the calibration cone having a design which allows an open flow passage between and low pressure side in this initial position. Thus, the valve device is always flushed through in its initial position. According to a further preferred embodiment, the differential pressure sensor only has contact with the då circuit when measurement takes place by said calibration cone allowing this communication only in a measuring position, at the actual measuring moment.
    This has the advantage that at all times outside the actual measurement there is no pressure / no load on the connected differential pressure sensor, which is an advantage especially with longer switch-on times.
    According to a further preferred embodiment, the device comprises at least one return tether, arranged in connection with the calibration cone, which return tester ensures that the calibration cone returns to the initial position after measuring in the measuring position. In this case, the device is always in this position when disconnecting from the system. This initial position is partly, according to the purpose above, the position for zero point calibration and also the position for flushing of the complete valve device. Thus, these steps, which are important for the quality of the measurement result, are always carried out before a measurement is started, which then eliminates the risk that these steps are forgotten, which is a problem with known solutions.
    In a further preferred embodiment, zero point calibration and flushing has been solved by these steps taking place automatically via an actuator or an actuator in combination with the above-mentioned return valve folded / which moves the calibration cone between its initial position and its measuring position. The device is always returned to the position for flushing and zero point calibration after the end of the measuring sequence, either by the actuator returning the device to this position or by the arm stored energy, preferably said spring, ensuring this. When the device is connected to or disconnected from a measuring point, the device thus always returns to its initial position, ie its flushing and zero point calibration position, with the consequence that these steps are ensured before the next measurement. In a further preferred embodiment, said actuator is controlled by means of a handset or a computer system. The possibility of communication with a computer system allows communication with property monitoring systems, so-called BMS systems (Building Management System). The remote control in turn allows the possibility to remotely calibrate and flush a number of valve devices and then measure, for example, a number of valves' expression with assured results and collect this data and gain control of the fate of the sound system and as a result adjust the sound system.
    Another disadvantage of today's solutions is that service personnel / adjusters have to, due to the manual handling, have to move to each valve in a building's uidsystem, which costs both time and effort. A direct advantage of the invention is thus that motor control of the actuator together with remote control allows service personnel / adjusters to operate from one or a few places in connection with the operating system.
    In known solutions, valve devices with protection against impermissible differential pressure levels are present through two safety valves. The reason why you have two safety valves is that when connecting the inlet and outlet of the valve device to a measuring system's measuring nipples, it is not possible to know in advance which of the measuring sides, inlet or outlet, receives the highest pressure. The two safety valves thus protect the differential pressure sensor against excessive pressures in both directions. In a preferred embodiment of the present invention, this is solved with a detail, a cone, which is advantageous from the point of view of function, manufacturing and cost. According to the invention, the protection function described above is always active, both in the measuring position of the device and in its flushing and zero point calibration position. This means that double protective fuels are obtained in the flushing and zero point calibration mode of the device. In summary, with the invention in question, a number of advantages have been obtained over existing constructions in connection with a measurement to be carried out: both measuring sides of the differential pressure sensor are outside the vid flow at zero point calibration, which means that the zero point becomes independent of fl uid flow rate and the pressure drop only opens the communication to the differential pressure sensor at the actual measuring torque, which means that for example during connection / disconnection and time outside the actual measurement there is no pressure / load against the differential pressure sensor, guaranteed zero calibration, which results in safer measurement results. in the valve device, which results in safer measurement results, the motor control allows both automation and remote control of the steps zero point calibration, flushing and measurement improved working environment for servi staff / adjusters. time and cost savings in connection with commissioning and service / maintenance the device allows communication with system for property monitoring, a so-called BMS system (Building Management System) valve device protects the connected differential pressure sensor against excessive differential pressures, where this protection function works regardless of which connection side connects to the high pressure side and this is solved with a detail double protection functions during flushing and zero point calibration The above preferred embodiments are stated in the dependent claims.
    The constructive design of the present invention is described by the following detailed description of embodiments of the invention with reference to the accompanying figures which show a preferred, but not limiting, embodiment of the invention. In addition, the invention further advances the state of the art in the field in various respects. This is realized in the present invention in that a device of the type described below is substantially as described in the characterizing part of claim 1.
    Brief description of the figures In detail represents in diametrical, partly schematic cross-sections or perspective views: - Fig. 1 shows a part of a fl uids system where a differential pressure measuring system is connected.
    Fig. 2a shows the detailed details of the complete valve device.
    Fig. 3a shows the complete valve device in its initial position, i.e. its flushing / zero point calibration position.
    Fig. 4 shows the complete valve device in measuring position.
    Fig. 5 a shows a detailed view of the safety valve in normal position.
    - Fig. 5b shows a detailed view of the safety valve in the triggered position.
    Detailed description of the figures Fig. 1 shows an example of a complete valve device 1 provided with actuator 2 where the valve device 1 is connected to a valve 3 via measuring hoses 4 to the valve measuring nipples 5. The figure also comprises a handset 6 for preferably wireless communication with the actuator 2 and i where applicable, communication with a computer or computer system.
    Fig. 2 shows detailed details of the complete valve device.
    The complete valve device consists of a valve housing 7, a safety valve cone 8, with return springs 9 on either side of the safety valve cone, a calibration cone 10, with a shaft 11, connected to the actuator 2 and a sensor holder 31 mounted on the valve housing 7. with a differential pressure sensor 12.
    The valve housing 7 has an inlet 13 and an outlet 14 where the measuring hoses 4 are connected and by inlet is meant the high-pressure side and by outlet is meant the low-pressure side. These sides can of course be the opposite, depending on how the connections end up in relation to the fl uidsystem's high / low pressure side. Furthermore, the valve housing has a first cavity 15 which is dimensionally coordinated with the outer dimensions of the safety valve cone 8. In the outer end 16 of the cavity 15 there is a safety valve stop 17 provided with sealing elements 18 and in connection with this stop there is the first return spring 9 where the safety valve stop 17 forms the base for the return spring. Between this return spring and the second return spring 9, located at the bottom 19 of the cavity 15, the safety valve cone 8 is placed and thus clamped between the two return springs. The safety valve cone preferably comprises two internally received cavities 24 in the axial direction relative to the safety valve cone, which cavities open at each end of the safety valve cone 8, and where each cavity, at its bottom, has a recess 25 towards the periphery of the cone. Externally, the safety valve cone 8 is provided with sealing elements 20 on the peripheral surface, on either side of the recesses 25.
    From the inlet 13 a channel 21 extends, via the cavity 15, at the return edge 9, and further up to a second cavity 22 which is dimensionally coordinated with the outer dimensions of the calibration cone 10. A second channel 23 fi extends to the cavity 22 from the outlet 14, via the bottom 19 of the cavity 15. In the cavity 22 is the calibration cone 10 which preferably comprises an internally received cavity 26 in the axial direction relative to the calibration cone and where the cavity extends through the entire calibration cone 10. length. Externally, the calibration cone 10 is provided with preferably two sealing elements 27 on the peripheral surface of each end. In the outer end 28 of the cavity 22 there is a stop lug 29 which is provided with sealing elements 30 and this stop lug 29 also constitutes attachment / holder of the actuator 2 and its shaft 11 which opens through the stop lug 29 and where the shaft 11 is attached to the calibration cone 10. Between the bottom of the cavity 22 and the calibration cone, a return spring 35 is clamped.
    From the peripheral surface of the cavity 22, channels 32 and 33 extend to the differential pressure sensor 12 in the sensor holder 31.
    Fig. 3 shows the complete valve device in its initial position, i.e. its flushing / zero point calibration position.
    At all times other than just when measuring, the valve device is in its initial position, its flushing / zero point calibration position. The device is always returned to the position for flushing and zero point calibration after the end of the measuring sequence, either by the actuator 2 returning the device to this position or by other stored energy, for example a return spring 35, ensuring this. In this initial position, the calibration cone 10 is located between the channels 21 and 23 and the two sealing elements 27 end up on either side of the channels 32 and 33, which has the consequence that the channels 32 and 33 are short-circuited and thus assume the same static pressure. Thus, the differential pressure sensor 12 becomes zero point calibrated and the calibration takes place outside the outflow due to the channels 32 and 33 connecting the cavity 22 at its peripheral surface, between the two sealing elements 27 which seal between the cavity 22 and the calibration cone 10. Flushing takes place simultaneously due to construction allows an open flow passage between high and low pressure side, fi from the inlet 13, via the channel 21, to the cavity 22, through the cavity 26 of the calibration cone 10 and further to the cavity 22, then to the channel 23 and then to the outlet 14. After this process the complete valve device is 1 flushed and free of trapped air and the valve device is zero point calibrated. Fig. 4 shows the complete valve device in measuring position.
    After rinsing and zero point calibration, the actuator 2, via the shaft 11, moves the calibration cone 10 in the axial direction towards the bottom 34 of the cavity 22, whereby the calibration cone comes into position for measurement. In this measuring position, the sealing elements 27, due to the displacement of the calibration cone 10, are located on either side of the channel 21 and thus seal between the cavity 22 and the calibration cone 10 and thus also the flushing passage, via the cavity 26, is closed. In addition, one of the sealing elements 27 in this position constitutes a barrier between the channels 32 and 33. The higher expression thus comes into contact with the differential pressure sensor 12 because the passage from the inlet 13, via the channel 21 to the peripheral surface of the cavity 22 and further via the channel 32 up to the differential pressure sensor 12 , is open. At the same time, the passage on the low pressure side is also open to the differential pressure sensor 12, from the outlet 14, via the channel 23 and the cavity 22 and further to the channel 33 and to the differential pressure sensor 12. The differential pressure is thus registered.
    To minimize the force required to move the calibration cone 10 between the calibration / coil position and the measuring position and vice versa, the calibration cone 10 is balanced through the hollow tube 26 in such a way that the calibration cone always has the same pressure level on both sides of its top and bottom. say between the bottom of the cavity 22 and the calibration cone and between the stop lug 29 and the calibration cone. Thus, only the frictional force between the sealing elements 27 and the wall of the cavity 22 needs to be overcome.
    Fig. Sa shows the safety valve in normal position.
    When the complete valve device 1 is not subjected to a higher differential pressure than the assumed protective action, which consists of return springs 9 and the safety valve cone 8 is dimensioned for, the safety valve cone is in a position between the two return springs 9 and the ducts 10 15 20 10 21 and 23. In this position the passage through the cavity 24 and recess 25 of the safety valve cone 8 is closed and the communication between the inlet 13 and the outlet 14 is thus not possible. The passage of fl uid between the high and low pressure sides is made impossible in this position due to the sealing which takes place by means of the sealing elements 20 on either side of the mouth of the recesses 25 against the wall of the cavity 15. This is the normal measuring position of the valve device 1.
    Fig. 5b shows the safety valve in the released position.
    In the event that the differential pressure exceeds the value for which the safety valve cone 8 together with the return springs 9 is dimensioned, the safety valve cone 8 is pressed in the direction of the side having the lowest pressure, the return spring 9 on this side being compressed. Thus, the passage between the high and low pressure side is opened, and fl uiden passes the inlet 13, to the first cavity 15, through the cavity 24 and recess 25 of the safety valve cone 8 and further out towards the outlet 14. Conversely, fl uiden can flow in the opposite direction if the high and low pressure side are reverse. Thus, through one and the same detail / friction, a protection against passing too high a pressure to the connected differential pressure sensor 12 has been obtained and this protection works in both directions. 10 15 20 25 1 = valve device 3 = valve 5 = measuring nipple 7 = valve housing 9 = return spring 1 1 = axle 1 1 3 = inlet 1 5 = cavity 1 7 = safety valve stop 1 9 = bottom 2 1 = channel 23 = channel 25 = recess 27 = sealing element 29 = stop lug 3 1 = sensor holder 3 3 = channel spring 3 5 = return spring 11 PARTS LIST 2 = actuator 4 = measuring element 6 = hand unit 8 = safety valve bearing 1 0 = calibration cone 12 = differential pressure sensor 1 4 = outlet 1 outlet = outlet 1 = sealing element 22 = cavity 24 = cavity 26 = cavity 28 = outer end 3 0 = sealing element 3 2 = kana1 3 4 = bottom
    权利要求:
    Claims (7)
    [1]
    A device included in a system for measuring differential pressure in an outlet system and wherein the device is a valve device (1) and comprises a valve housing (7) with an inlet (13) and an outlet (14) for connection to the outlet system, ducts ( 32, 33) for communication with a differential pressure sensor (12) for recording the differential pressure, a cavity (22) in contact with the channels (32, 33) where the cavity (22) comprises a calibration cone (10) which is removable in the cavity (22). between a measuring position and a position for zero point calibration / flushing of the valve device (1), characterized in that the calibration cone (10) separates the differential pressure sensor (12) from the system in cases where the measuring position of the device is not present, i.e. in its initial position, by ) comprises sealing elements (27) which sealing elements shield the channels (32, 33) from the cavity (22).
    [2]
    Device according to claim 1, characterized in that a flushing function is obtained in cases where the measuring position of the device is not present, i.e. in its initial position, in that the calibration cone (10) has a design which allows an open flow passage between high and low pressure side, from the inlet (13), via a channel (21), to the cavity (22) in the valve housing (7), through the cavity (26) of the calibration cone (10) and further to the cavity (22), then to a channel (23) and then to the outlet (14).
    [3]
    Device according to claims 1-2, characterized in that the calibration cone (10) in its measuring position, leads to communication between the fl uid system and the differential pressure sensor (12), in that the sealing element (27) of the calibration cone (10) does not shield the channels (3 33) fi ^ ån hålrummet (22). 10 15 20 13
    [4]
    Device according to Claims 1 to 3, characterized in that the calibration cone (10) is arranged to always return to its initial position, i.e. when the measuring position is not present, by ensuring that stored energy, preferably a return spring (35), ensures this.
    [5]
    Device according to claims 1-4, characterized in that the valve device (1) comprises an actuator (2) which is arranged to change the position of the calibration cone (10) in the cavity (22).
    [6]
    Device according to Claim 5, characterized in that the actuator (2) is scarred.
    [7]
    Device according to one of Claims 1 to 6, characterized in that the valve device (1) comprises a cavity (15) with a safety valve cone (8), which safety valve cone protects the differential pressure sensor (12) against excessive differential pressure by, the safety valve cone (8) being arranged to, at differential pressure higher than a dimensioning value, be moved in the direction of the low-pressure side and thereby open a passage between the high-pressure and low-pressure side, from the inlet (13), i.e. the high-pressure side, to the outlet (14), i.e. the low-pressure side, via the cavity (15) in the valve housing (7), via the cavity (24) and recess (25) of the safety valve cone (8), whereby a pressure equalization takes place.
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    法律状态:
    2019-01-29| NUG| Patent has lapsed|
    优先权:
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