Arrangement for increasing the response speed and safety shutdown of a temperature controller in hot water appliances, especially in instantaneous water heaters

Description

[0001] Arrangement for increasing the response speed and safety shutdown of a temperature controller in hot water appliances, especially in instantaneous water heaters. The invention relates to an arrangement for increasing the response speed of a device operating in the thermal range of the domestic water from hot water appliances, especially in instantaneous water heaters, built-in, temperature-sensitive organ of a thermostat during the dispensing process, in which the cold water flowing into the container is guided by special conductive agents to the vicinity of the temperature-sensitive The heat supply is automatically released after the water flow begins and after the flow is complete. Water flow is automatically shut off.

[0002] It is known in small hot water storage tanks and instantaneous water heaters to regulate the heat supply, e.g. by electric resistance heating, It should be switched on as soon as possible after the start of water withdrawal, approximately simultaneously with this, so that the water withdrawal necessitates The upcoming new heating cycle for restoring the original amount of hot water is brought forward in time, and: that in the case of the instantaneous water heater the The cold water flowing into it immediately after the tap starts to be drawn can be heated.

[0003] In hot water storage tanks, the heating begins during the drawing process and lasts for the most part during the subsequent period. The situation is different with an instantaneous water heater. With this type, it is necessary that the water is drawn immediately after... Once the dispensing process is complete, the heat supply is shut off, otherwise... If the hot water remaining in the container is switched off later, it can overheat, which can lead to problems if the device is repeatedly switched off. The boiling point may be reached with successive dispensing, and in high-pressure appliances, excessively high steam pressure may also occur. Should a For instantaneous water heaters to constantly supply water at the same temperature, this requires that both the supply and the shut-off of Water and heat are transferred as simultaneously as possible. This has already been achieved through the mechanical coupling of a device located in the watercourse. pressure-sensitive organ with a valve located in the water path on the one hand and a switching device for heat supply, for example by electric current... However, such a device has significant disadvantages due to pressure fluctuations and its moving parts.

[0004] On the other hand, it has been proposed to thermally couple the flow of water into the device and the heat input, by introducing cold water to a protective tube located inside the container and surrounded by hot container water at the start of dispensing, in which contains by far the temperature-sensitive part of a thermostat. The focus here has been limited to the thermostat itself. to switch on somewhat faster after dispensing begins. However, shutting off the heat supply after dispensing ends is achieved using the aforementioned method. Cold water flow is delayed rather than accelerated, since the thermostat's protective tube is often replaced by an artificial cold water jacket in the case of coaxial installation. The cold water pipe is still surrounded by cold water, while the actual part of the tank interior is at operating temperature or even overheating. has.

[0005] The object of the invention is to control both the heat supply immediately after the start of dispensing and its shutdown immediately after the end of dispensing. to be achieved by a temperature-sensitive element of a thermostat. According to the invention, this is achieved with an arrangement to increase the Response speed of a temperature-sensitive organ of a thermostat in a hot water appliance of the type mentioned above This is achieved by the fact that the water inlet pipe, which runs parallel to the temperature-sensitive organ without a protective tube, has a lateral effect, directed towards the area close to this The temperature-sensitive organ has directed openings and the water inlet pipe together with the temperature-sensitive The organ is surrounded by a perforated sheath to such an extent that the temperature-sensitive organ is protected in the event of activation of the Thermostats from the water inlet pipe as well as, conversely, in the case of the thermostat being switched off from the hot water outside the The guide device is subjected to pressure from all sides, quickly and directly.

[0006] With the aid of such an arrangement, the heating element of the device is also protected against drying out, since at the beginning of the drying process The further rising temperature of the radiator is transmitted via the same conducting device and in the same direction to the temperature-sensitive organ. has an effect.

[0007] Preferably, the cross-section of the guide jacket can have a C-profile that extends along its entire length around the parallel and on the Pipes for water inlet and thermal expansion (heat sensor) are arranged along the longer profile axis.

[0008] Any other temperature-sensitive component can be used in place of the thermal expansion tube. This arrangement is intended to The aim is that, when drawing cold water through lateral openings directed towards the thermal expansion pipe along the The water inlet pipe, with the aid of the selected profile of the guide device, exerts pressure on the thermal expansion pipe over its entire circumference. The perforated guide jacket has the task of reducing the displacement of hot water at the thermal expansion pipe, especially in the area of ​​the to favor the side of the thermal expansion pipe facing away from the direction of cold water impact. Furthermore, this guide jacket... Cold water is distributed evenly to the surrounding radiators, both in height and along the circumference.

[0009] In particular, the guide jacket at the end of the tap is designed for heat exchange in the reverse direction under much lower pressure, i.e. important for the rapid application of hot water to the thermal expansion pipe from outside the guide device.

[0010] The arrangement according to the invention not only leads to the desired fast response speed of the thermostat in normal operation This property is the reason for selecting the C-profile of the guide device according to the invention. This leads to the following: If this guide device surrounding the two pipes is positioned close to the radiator with its open longitudinal side resulting from the profile, then in the event of excessive radiator temperatures, the guide device acts as a barrier directed against the thermal expansion. Collecting device for the heat emitted by the nearby radiator to all three heat transfer modes, mainly for the heat radiation emanating from the radiator.

[0011] This applies both when the radiator temperature is exceeded due to an excessive increase in the desired water temperature and preferably for the case of dry running, in which the radiation component represents by far the main part of the heat transfer.

[0012] In the described anomalous cases, in particular when the radiator runs dry, the safety shutdown is activated. a thermostat. This means that after a certain cooling period, caused by this safety shutdown, the thermostat... The heat supply is then released again. The radiator therefore temporarily dries out. This is the case until the safety shut-off in the radiator occurs. stored heat that then flows onto the hot- The water appliance increases the temperature before the temperature begins to decrease.

[0013] These temporary thermal overload phenomena during dry running, which are caused by the hot water appliance over time which cannot be tolerated without damage, but can be further avoided according to the invention by extending the heating-free period of the described The cycle is extended by artificially slowing the cooling of the medium (steam, air) surrounding the thermal expansion tube. This is for example, through thermal insulation – not common in conventional instantaneous water heaters, but common in hot water storage tanks. water tank fulfills the requirements that, at the same time, during periods without water withdrawal, i.e., in storage mode, the heat losses are known to be kept to an acceptable level. The dimension is reduced. With this thermal insulation, the switching period increases to many hours.

[0014] Instantaneous water heaters that can also function as hot water storage tanks are additionally equipped with a manual switch for The heat supply and shut-off valve is equipped to prevent water from being drawn during long periods without water use, for example in a household in the early morning. In the afternoon and especially at night, for economic reasons, the stored water is not used due to heat losses from heat input. to avoid having to maintain a constant temperature.

[0015] Since the described thermal insulation reduces the switching period of the thermostat to many hours when the radiator dries out If the heat is extended, it can be safely assumed that the usual manual heat blockage, which is done several times a day, will cause the heat to be removed. and this occurs primarily in the evening, when the heat supply is otherwise prevented by the thermostat. Furthermore, the drying out of the The heating system should only be shut off during a reduction in mains water pressure and therefore temporarily; it is also preferably used as a second safety measure, which mainly only activates before a disaster occurs, and is still sensitive to overheating and heat-conducting with the radiator. A connected, fusible link temperature cut-off device is installed, which in itself only provides a single heat cut-off. can do.

[0016] . The following illustration shows an arrangement according to the invention. Figure i shows an instantaneous water heater largely in The vertical center section and Fig. z a horizontal section through the instantaneous water heater along line 2-2 in Fig. i. The instantaneous water heater consists of specifically from the water tank i, which is surrounded by a thermal insulation layer 2 with an outer protective jacket 3. Into the water tank The overflow pipe q and the inlet pipe 5, which is provided lengthwise with lateral openings 6 that point towards the are located near pipe 5 and the parallel-running temperature sensor 7 of a thermostat (not shown). Inlet pipe 5 and temperature sensor 7 are enclosed by a guide plate 9 with many openings 8 and a C-section, the open side of which faces a nearby The section of the electric heating element ii shown. The heating element ii and a temperature cut-off device 12, which acts as a second fuse shortly before When the disaster occurs, the devices are attached to a container flange 13.

[0017] During periods when no water is being drawn, the water in the container is kept in a hot water ready state by means of the thermostat (heat sensor 7). The temperature sensor 7 is held immediately after the start of the draw-off period by the water flowing from the network into the inlet pipe and from its openings 6. The outflowing cold water is applied directly along its length and around its entire circumference with the aid of the guide plate 9, so that almost without delay the Switching on the electric heating element ii is triggered.

[0018] The cold water flows quickly and evenly through the openings 8 and the open side io of the guide plate 9 into the actual Water tank i, where it is heated by the electric heating element ii before 4#s flows out as hot water via the overflow pipe q.

[0019] The guide plate 9 is particularly important for switching off the electric heating element ii immediately after the end of the tap, since after When the cold water supply ceases and the current subsides, a water circulation through these openings 8 and 10 begins and is directed towards In this way, hot container water quickly enters the guide plate g, where, due to the profile shape, it is carried towards the heat sensor 9. This is achieved. In particular, the hotter container water originating from the vicinity of the nearby, hot radiator ii contributes to this. Hot water is applied to the heat sensor 7, which consequently responds more quickly.

[0020] In the event of dry running, the radiator, which heats up to an unacceptably high temperature, emits heat by radiation. A sufficiently large portion is captured in the guide plate 9 and, due to its C-profile, directed towards the heat sensor 7, so that it quickly is brought to the point of discussion.

Claims

[0021] PATENT CLAIMS: i. Arrangement for increasing the response speed of a device in the thermal range of domestic hot water Hot water appliances, especially instantaneous water heaters, built-in temperature-sensitive component of a thermostat during the dispensing process, at in which the cold water flowing into the container is brought into close proximity to the temperature-sensitive organ by means of special conducting agents, characterized in that the water inlet pipe (5) which is guided parallel to the temperature-sensitive organ (7) without a protective tube has lateral [flanges] on the The temperature-sensitive organ (7) located near this organ has directed openings (6) and the water inlet pipe (5) together with the temperature-sensitive organ (7) of is surrounded by a jacket (9) provided with holes (8) to such an extent that the temperature-sensitive organ is protected in the event that the thermostat is switched on. from the water inlet pipe (5) as well as conversely in the case of the thermostat being switched off from the hot water outside the guide device (9) from all sides, quickly and directly, is acted upon. e.g., arrangement according to claim 1, characterized in that it is located near the preferably electric heating element (ii) is arranged.

3. Arrangement according to claim i or a, characterized in that the cross-section of the guide sheath (9) is a A C-profile, the open side of which faces the radiator (ii).

4. Arrangement according to one of claims 1 to 3, characterized in that the water tank is surrounded in a known manner by a thermal insulation layer (a). Considered documents: German Patent No. 885,471.