• 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:
    The device has a main circuit (I), which comprises a load (99), a circulation heater (2) and a pump (m10). Water serves as a working medium in this cycle. The device further comprises a device (5) for keeping constant pressure in the water of the circuit (I). This pressure holding device (5) contains a container (10) in which a heating device (E27) is located. The interior of the container (10) of the pressure holder (5) is fluidly connected to the interior of the main circuit (I) by means of a pipe section (27). The container (10) of the pressure holder (5) is located above the circulation heater (2). The volume of the container (10) of the pressure holder (5) is smaller than the volume of the main circuit (I).
    公开号:CH713048A2
    申请号:CH01379/16
    申请日:2016-10-14
    公开日:2018-04-30
    发明作者:Peterer Roland；Zürcher Michael；Bucher Beno；Palazzolo Raffael
    申请人:Regloplas Ag；
    IPC主号:
    专利说明:

    Description: The present invention relates to a method for ensuring the operation of a circuit which comprises a consumer, a circulation heater and a pump connected in series, water serving as a working medium in this circuit, which may have fluctuating temperatures, as well a device for carrying out this method.
    For example, in the injection molding and die casting machines, water serves as the working medium which circulates in the main circuit of such machines. During operation of such a machine, e.g. In an injection molding machine or a die casting machine, the temperature of water in the main circuit of the machine in which the load is switched on fluctuates. As a consumer, the tool can serve the machine. Due to the changes in the temperature of water caused by the operation of the consumer, the volume of this working fluid also changes. However, as the volume of water changes, so does the pressure in the main circuit. In order for such machines to work undisturbed, it is known, for example, that the surplus water, which was due to the thermal expansion of water in the increase in temperature in the main circuit, is drained from the circulation. If the temperature of water drops after that, then the now missing amount of water in the main circuit must be refilled.
    It is known to use for such purposes devices which are e.g. Use valves, pumps, and other mechanical components to compensate for fluctuations in the volume of water, and thus also fluctuations in main circuit pressure. Such mechanical components work at high temperatures of water as well as at high pressures in the water. These circumstances place extraordinarily high demands on the functionality of such mechanical components of the main circuit. The mentioned circumstances can not only affect the functionality of the mechanical components, but also shorten the life of the same.
    Particular problems during operation of the mentioned machines arise when the pressure in the main circuit is too high. Namely, the main circuit has a certain thermal inertia, so that it takes a relatively long time until the temperature drops so much by heat convection in the main circuit that the pressure in the main circuit reaches the desired operating value again. This affects the performance of the machines.
    The object of the present invention is to eliminate the disadvantages mentioned as well as other disadvantages of the prior art.
    This object is achieved according to the invention in the device of the type mentioned above, as defined in the characterizing part of patent claim 1.
    Hereinafter, embodiments of the present device will be explained in more detail with reference to the accompanying drawings. It shows:
    1 is a circuit diagram of the present device,
    2 enlarges a first section of the circuit diagram according to FIG. 1,
    3 shows in a vertical section a pressure holding device of the device according to FIG. 1, and FIG. 4 enlarges a second section of the circuit diagram according to FIG. 1.
    The present device can also be called as a temperature control unit. The present device has a first main circuit I (FIGS. 1 and 2), which comprises a consumer 99, a circulation heater E21 and a pump M10. These components of the main circuit I are connected in series by means of a main line 8. In this case, the circulation heater E21 is connected between the pump M10 and the consumer 99. The existing water in this circuit I serves as a working medium. The temperature of water in the first main circuit I may be subject to considerable fluctuations due to the action of the consumer 99. The present device also has a device 5 for keeping constant pressure in the water of the first main circuit I. This device 5 is also called pressure holder 5 below.
    The present device also has a second main circuit II, which among other things serves to regulate the pressure and the water level in the pressure holder 5.
    The circulation heating 2 in the first main circuit I has a container 20 (FIG. 2), in which a heating device E21 of this circulation heating I is located. The container 20 includes an upper lid 21, a lower lid or bottom 22 and a cylindrical shell 23. The upper and the lower end opening of the shell 23 are closed by means of the lid 21 and 22 respectively.
    The circulation heater 2 is provided with a pressure sensor B8, which monitors the pressure in the present device. This pressure sensor B8 is attached to the cylindrical shell 23 of the container 20 of the circulation heater 2. In the container casing 23, an opening (not shown) is executed, which is associated with the pressure sensor B8 and through which the pressure sensor B8 is connected to the interior of the main circuit I. The circulation heater 2 is further equipped with a safety thermostat F5, which monitors the operation of the circulation heater 2. To further increase the reliability of the cycle heating 2, a safety valve 57 is connected to the interior of the container 20 of the cycle heater 2.
    The pump M10 is connected in series for circulation heating 2 and the consumer 99 as a water heater. Parallel to this first pump M10, a bypass circuit 58 is connected. One of the end parts of this bypass circuit 58 is connected to the container 20 of the circulation heater 2. The other end portion of the bypass circuit 58 is connected to the main line 8 of the main circuit I. This connection point is located between the pump M10 and the consumer 99. Between the pump M10 and the consumer 99 are still a sensor B1 for the temperature in the interior of the main circuit I and a sensor B8.1 for the flow pressure in the main circuit I connected. At the return region of the main circuit 8, a first check valve 56.1 and a solenoid valve Y13 are connected to the suction.
    The pressure holding device 5 (FIGS. 2 and 3) comprises a container 10 which has an upper lid 11, a lower lid or bottom 12 and a cylindrical jacket 13. The upper and the lower end opening of the shell 13 are closed by means of the lid 11 and 12, respectively. A heater E27 is located inside the container 10. A device for venting the first main circuit I is provided. This venting device comprises a pipe connection 17, which is mounted below the upper lid 11 on the wall 13 of the container 10 of the pressure holding device 5. The venting device further comprises a valve Y8, which is located in the second main circuit II. This valve Y8 is connected between the pipe port 17 and the cooling liquid outlet line OUT. The coolant used is water. The pipe connection 17 is located at the highest point of the present device, so that this entire device can be vented by means of this device.
    The pressure holding device 5 is spatially higher than the circulation heating 2. This means that the bottom 12 of the container 10 of the pressure holding device 5 is above the upper lid 21 of the container 20 of the cycle heater 2. The volume of the container 10 of the pressure-maintaining device 5 is smaller than the volume of the container 20 of the circulation heater 2 in the main circuit I.
    A first sensor 31 (Fig. 3) for the level of water level in the container 10 of the pressure holding device 5 is provided, which monitors the achievement of the highest permissible level of the water level in the container 10 of the pressure holding device 5. A second sensor 32 for the level of water level in the container 10 of the pressure holding device 5 is provided, which monitors the achievement of the lowest permissible level of the water level in the container 10 of the pressure holding device 5. The outputs of the water level sensors 31 and 32 are connected to switching devices S1 and S3, which control the supply of water into the pressure holding device 5 and the discharge of water from the pressure holding device 5.
    The heater E27 of the pressure holder 5 is disposed below the lower end 33 of the sensor 32 for the lowest allowable level of water. The heater E27 is located on the one hand at a distance from the lower end 33 of the sensor 32 for the lowest allowable level of water and on the other hand at a distance from the lower lid 12 of the container 10 of the pressure holding device 5. When the heater E27 is in operation, then forms Steam inside the container 10, above water. With the help of a double hatching 34 is water and with the aid of a simple hatching 35 steam in the interior of the container 10 of the pressure holding device 5 is indicated. By a proper control of the operation of the heater E27, the amount of steam 35 above the level of water 34 in the container 10 of the pressure holder 5 and thus also the height of the mirror of water 34 in the pressure holder 5 can be controlled.
    The present device also includes a control circuit which can control the proper operation of the heater E27 in the pressure holder 5 in dependence on the size of the water pressure in the circulation heater 2. The input of this control circuit is connected to a pressure sensor B8. The output of this control circuit is connected to the heater E27 in the pressure holder 5. This control circuit further includes a regulator, which is connected between the input and the output of the control circuit. This controller is designed so that it can control the operation of the heater E27 in the pressure holder 5 depending on the size of the water pressure in the circulation heater 2. The pressure sensor B8 may be fluidly connected to the interior of the container 20 of the circulation heater 2 or to the interior of the container 10 of the pressure holder 5.
    The interior of the container 10 of the pressure holding device 5 is fluidly connected to the interior of the main circuit I. This takes place in the case shown by means of a piece of pipe 27. This pipe section 27 extends between the bottom 12 of the container 10 of the pressure holding device 5 and the upper lid 21 of the container 20 of the cycle heater 2 and it connects these fluidly with each other. It is essential that the bottom 12 of the container 10 of the pressure holder 5 is above the upper lid 21 of the container 20 of the cycle heater 2. For the operation of the present device, it is important that the interior of the container 20 of the cycle heater 2, the interior of the pipe section 27 and the lower portion 34 of the container 20 of the pressure holder 5 are filled with water. Because of this, the steam 35, which is located above water 34 in the pressure holder 5, exert influence on the pressure in the first main circuit I.
    By means of the heater E27, the pressure increase in the entire water cycle I is made. The amount of pressure is adjusted via the pressure in the steam 35 above water 34 in the pressure holder 5. The pressure is thus adjusted via the vapor pressure of the water at a certain temperature. This target pressure to be controlled is regulated by the control / regulation. The target pressure to be controlled depends on the desired flow temperature in the subordinate main circuit of the water to the temperature of the device.
    Arrangements in which forces are transmitted by means of liquids, called hydraulic systems. In the present case, the hydraulic system has cavities, of which the first cavity is bounded by the walls of the container 10 of the pressure holder 5 and the second cavity through the walls of the first main circuit I, wherein such cavities are fluidly connected to each other by means of the pipe section 27. In the transmission of forces in hydraulic systems, the cross sections of the cavities are important. If the force acts from the cavity, which has the smaller cross-section, then known, the forces which are greater inside the cavity with the larger cross section than the forces acting in the cavity with the smaller cross section. The pressure exerted by the smaller cavity on the larger cavity is sometimes also called stamping pressure. If, in the present case, the pressure holder 5 has the smaller volume and the smaller cross-section, then by means of such a pressure holder 5 pressure in the other cavity can be changed within certain limits.
    It can be assumed that the pressure in the water in the first main circuit I has a high base value during operation of the machine. Because of the action of the working tool that results during operation of the machine, this basic value of pressure may be subject to variations. In the present case, it is necessary to intercept the fluctuations of the basic value of the pressure in the first main circuit I, so that the machine can work quickly and trouble-free. Such fluctuations in the pressure value have relatively small amplitudes. Such pressure fluctuations can be intercepted by the operation of the pressure holder 5, in the manner indicated above. This is done by a suitably controlled operation of the Heizköpers E27 in the pressure holder 5, which generates steam 35 in the pressure holder 5 according to the abgefangenden fluctuations in the pressure value in the main circuit I.
    The outputs of the water level sensor 31 and 32 are connected to means which can control the supply of cooling water in the circulation heater 2 and the discharge of water from the circulation heater 2. The means for supplying cooling water have a pump M2, a first line L1 and a valve Y2, which are connected in series. This series circuit is connected at one end to the inlet ON for the cooling water and at the other end to that region of the container 20 of the circulation heater 2, which is located below the upper cover 21 of the container 20. The means for discharging water from the circulation heater 2 have a valve Y22, which is interposed in a second line L2. The inlet of this second conduit L2 is connected to the bottom 22 of the container 20 of the circulation heater 2 or at least to that region of the side wall 23 of the container 20 of the circulation heater 2, which is in the vicinity of the bottom 22 of the container 20. The output of the second line L2 is connected to the outlet OUT of the cooling water from the second main circuit II.
    Further and also essential problems prepares the fact that the first main circuit I has a considerable thermal inertia. During operation of the machine it is sometimes necessary to reduce the temperature of water in the main circuit I as quickly as possible. This can be achieved by putting the first pump M2 into operation and opening the valve Y2. Through the line L1 fresh cooling water flows into the upper region of the housing 20 of the cycle heater 2. The excess water in this housing 20 thereby passes out through the bottom portion 22 of this cycle heater 2, through the line L2 in the water outlet OFF, after the valve Y22 was opened. As a result, the temperature in the circulation heater 2 and thus also in the entire first main circuit I is reduced in a rapid manner.
    The initial state of the device when it is switched on is such that there is no water in the device. The device is filled by means of the pump M2 and opened solenoid valve Y2. During the filling process, the solenoid valve Y8 remains open so that the air displaced by the water can escape from the device. The filling is completed as soon as the level probe S3 or 32 has contact with the water in the pressure holder 5. The device is now ready for use.
    Due to the pump M10 must prevail overpressure in the device. This pressure is impressed on the device by means of the pressure holder 5. For this, the pressure holder heater E27 is switched on. The water temperature in the pressure holder 5 is brought to over 100 degrees C. From 100 degrees C arises above the water level in the pressure holder 5, a vapor phase 32 of water. The pressure holder heater E27 remains switched on until the pressure, measured with the pressure transmitter B8 on the circulation heater E21, has reached the predetermined value. The circulation heater E21 remains switched off during this period. This means that the main circuit I, ie the circuit which is e.g. connected to a mold, still has the same water temperature as when filling the device with water.
    Once the default pressure in the main circuit I is reached, the water in the main circuit I can be heated by the circulation heater E21. The water temperature in the pressure holder 5 is always slightly higher than the water temperature in the main circuit I, to ensure the pressure superposition in the main circuit I.
    If the level probe S3 or 32 loses contact with water phase 31 in the pressure holder 5, this means that there is too little water in the device. The pressure holder heater E27 (Figure 3) is no longer completely surrounded by water and may be damaged when switched on. To avoid this, once that is too low level
    权利要求:
    Claims (11)
    [1]
    was detected, the device supplied by turning on the pump M2 and the opening of the valve Y2 water. This happens until the level probe S3 or 32 again has contact with the water phase. If the level probe S1 or 31 comes into contact with the water phase, then this means that there is too much water in the device. If the volume of the vapor phase 35 were to become even smaller, the device would lose the desired properties. As soon as the too high water level in the pressure holder has been detected, the solenoid valve Y22 is opened. The valve Y22 remains open until the water phase no longer has contact with the level probe S1 or 31. In normal operation, the reduction of the pressure in the water occurs by means of the temperature reduction of the water in the pressure holder 5, which occurs when switching off the heater. This temperature drop is mainly due to convection. If, however, the pressure has to be lowered quickly, the pump M2 is switched on and the solenoid valve Y2.8 is opened. Cold water is pressed into the pressure holder 5 by means of a nozzle 40 (FIG. The cold water reduces the temperature of the steam and water in the pressure holder 5, resulting in a lower temperature. Because of this lower temperature prevails in the device thus also a lower pressure. When switching off the device is to ensure the lack of pressure in this, the device rinsed. The flushing is done by switching on the pump M2 and by opening the two valves Y2 and Y2.8 With this switching of the valves Y2 and Y2.8 the pressure holder 5 is completely flowed through with cold water, so that the device is depressurized after a short period of time. The device turns off. The pressure holder 5 has the container 10, in which water 34 and water vapor 35 occur simultaneously. Important is the presence of these two phases. Water and steam keep their equilibrium depending on the temperature. This means that the pressure in the container 10 of the pressure holder 5 and thus in the entire device depends only on the temperature in the pressure holder 5. With the pressure holder 5, the device can be impressed only by means of the temperature in the pressure holder 5, a certain pressure. Volume fluctuations of water in the main circuit I are absorbed by the pressure holder, without the pressure in the main circuit I changes. The heater E27 provides the necessary energy for heating the water in the pressure holder 5. The temperature of water directly determines the static pressure in the device. The pressure is transmitted via the first connecting line 27 to the main line 8 of the main circuit I. Important for the function of the present device is the simultaneous presence of the steam and the water phase 35 and 34 in the container 10 of the pressure holder 5. This condition is ensured by means of the two level probes S1 and S3 or 31 and 32. As long as the level probe has low S3 or 32 contact with the water phase, sufficient water is present in the pressure holder 5 and it requires no action. If this probe S3 or 32 loses contact with the water, the device is supplied with water by means of the pump M2 until this probe S3 or 32 again has contact with the water phase. If the probe has reached high S1 or 31 contact with the water phase in the pressure holder 5, water must be drained from the device via valve Y22. It is true that the second main circuit II, similar to the known devices of the same type, also has mechanical components such as pumps and valves. However, in the second main circuit II of the present device circulates only cooling water, which can not affect the functionality and the life of such components. Hot water circulates in the present device alone in the first main circuit I. In order to achieve the required changes in the pressure in the first main circuit I, no mechanical components are used. This is because these pressure changes are achieved exclusively by a suitable control of the operation of the heater E27 in the pressure holder 5. claims
    A method of ensuring the operation of a circuit (I) comprising a load (99), a circulation heater (2) and a pump (M10) connected in series, with water as the working fluid in that circuit (I) and may have fluctuating temperatures, characterized in that by means of a circuit (I) associated heating device (E27) pressure changes in this circuit (I) can be achieved, via the setting of a specific vapor pressure.
    [2]
    2. The method according to claim 1, characterized in that a pressure reduction in the circuit (I) by means of supply of cold water in this circuit (I) is achieved.
    [3]
    3. A device for carrying out the method according to claim 1, characterized in that a device (5) for adjusting pressure in the water of the circuit (I) is provided, and that this device (5) for adjusting pressure in the water cycle (I) is fluidly connected to this main circuit (I).
    [4]
    4. Device according to claim 3, characterized in that the pressure holding device (5) has a container (10), which is arranged above the circulation heating (2) that the heating device (E27) in the interior of the container (10) of the pressure holding device ( 5), and that the interior of this container (10) is fluidly connected to the interior of the circuit (I).
    [5]
    5. The device according to claim 3, characterized in that the circulation heating (2) has a container (20) in which a radiator (E21) is that the interior of the container (10) of the pressure holding device (5) to the interior of the Container (20) of the circulation heating (2) is fluidly connected and that the volume of the container (10) of the pressure holding device (5) is smaller than the volume of the container (20) of the circulation heater (2).
    [6]
    6. Device according to claim 5, characterized in that the bottom (12) of the container (10) of the pressure holding device (5) is arranged higher than the ceiling (21) of the container (20) of the circulation heater (2), and that a piece of pipe (27) is provided, which extends between the bottom (12) of the container (10) of the pressure holding device (5) and the ceiling (21) of the container (20) of the circulation heating (2) and fluidly connects them together.
    [7]
    7. Device according to claim 4, characterized in that the container (10) of the pressure holding device (5) is provided with a venting device, that this venting device comprises a pipe connection (17) which below the upper lid (11) on the wall (13 ) of the container (10) of the pressure holding device (5) is mounted such that the ventilation device further comprises a valve (V8) located in the second main circuit (II), that valve (Y8) between the pipe connection (17) and the outlet line (OFF) is switched.
    [8]
    8. Device according to claim 3, characterized in that a control circuit is provided, that the input of this control circuit to a pressure sensor (B8) is connected, that the output of the control circuit to the heater (E27) in the pressure holding device (5) is connected, that the control circuit has a regulator connected between the input and the output of the control circuit, and that the regulator is designed to control the operation of the heater (E27) in the pressure maintaining device (5) in dependence on the magnitude of the water pressure in the circulation heating (2) can control.
    [9]
    9. Device according to claim 8, characterized in that the pressure sensor (B8) to the interior of the container (20) of the circulation heating (2) or to the interior of the container (10) of the pressure holder (5) is connected fluidly.
    [10]
    10. Device according to claim 1, characterized in that a first sensor (31) for the level of the water level in the container (10) of the pressure holding device (5) is provided, which the achievement of the highest permissible level of the water level in said container (10). that a second water level sensor (32) is provided in the container (10) of the pressure maintaining device (5) capable of monitoring the attainment of the lowest level of water level in said container (10), and that the outputs this water level sensor (31,32) are connected to means which can control the supply of water in the circulation heating (2) and the discharge of water from this circulation heating (2).
    [11]
    11. The device according to claim 10, characterized in that the means for supplying water into the circulation heating (2) comprises a pump (M2), a first line (L1) and a valve (Y2), which are connected in series, that this series of circuits is connected at one end to the water inlet (ON) and at the other end to that region of the container (20) of the circulation heater (2) located below the upper cover (21) of the container (20), that the means for discharging water the circuit heating (2) have a valve (Y22) which is interposed in a second line, that the input of the second line (L2) to the bottom (22) of the container (20) of the circulation heater (2) or to that region of Side wall (23) of the container (20) of the circulation heater (2) is connected, which is in the vicinity of the bottom (22) of the circulation container (20) and that the end of the second line (L2) to the outlet (OFF) of Cooling water from the Einri connected.
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    同族专利:
    公开号 | 公开日
    CH713048B1|2021-12-30|
    WO2018068157A1|2018-04-19|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    DE1579317A1|1965-12-28|1970-07-30|Svenska Gummifabriks Aktiebola|Method for maintaining a certain pressure in a hot and cooling water circulation system for vulcanizing presses, in particular for tire vulcanization|
    CS180312B1|1975-10-24|1977-12-30|Michal Kostura|Equipment for automatic temperature control of metallic casting moulds|
    US4680001A|1984-11-28|1987-07-14|Application Engineering Corporation|Passive mold cooling and heating system|
    AUPP403398A0|1998-06-11|1998-07-02|James, Malcolm Barry|Temperature control method and apparatus|
    CN201304712Y|2008-10-16|2009-09-09|王�忠|Mould temperature control system|
    ES2676118T3|2014-06-10|2018-07-16|Tecnoidee Srl|Device or circuit of thermoregulation molds or high temperature systems in general|
    法律状态:
    优先权:
    申请号 | 申请日 | 专利标题
    CH01379/16A|CH713048B1|2016-10-14|2016-10-14|Method and device for ensuring the operation of a circuit.|CH01379/16A| CH713048B1|2016-10-14|2016-10-14|Method and device for ensuring the operation of a circuit.|
    PCT/CH2017/000092| WO2018068157A1|2016-10-14|2017-10-13|Method and apparatus for guaranteeing the operation of a circuit|
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