Domestic heating unit

Abstract

A domestic appliance heating unit (100) is provided, which has a plastic housing (110) with an inlet (111), an outlet (112) and an open upper end (114), and a heating flange (200) which can be inserted into the plastic housing (110) through the open upper end (114) and can be fastened in or on the open end (114) of the plastic housing (110) by means of a locking ring (120).

Description

[0001] The present invention relates to a domestic heating unit and a domestic appliance.

[0002] Heating units, and in particular electric heating units, can be used in a domestic appliance to heat water.

[0003] In an instantaneous water heater, for example, a bare wire heating unit can be used to heat the water flowing through.

[0004] It is desirable to provide a compact heating unit that allows improved control.

[0005] This object is achieved by a domestic appliance heating unit according to claim 1 and by a domestic appliance according to claim 5.

[0006] Thus, a domestic heating unit is provided with a housing for accommodating a heating flange. The housing is made of plastic and has an inlet and an outlet. The housing can be essentially cylindrical, i.e., the casing of the housing is cylindrical. The heating flange can optionally have multiple heating elements.

[0007] The housing may have a first open end for receiving the heating flange. The heating flange may be secured to the open end by means of a locking ring at one end of the housing.

[0008] The heating flange may comprise a flange plate and first heating elements and second heating elements. The first heating elements may have a first heating power, and the second heating elements may have a second heating power, which may be greater than the first heating power. The flange plate may close the open end of the housing. The flange plate may be secured to the first open end by means of the locking ring.

[0009] According to one aspect of the present invention, the first and second heating elements can each be electrically controlled separately.

[0010] This is advantageous because it allows for fine-tuned adjustment of the heating unit's heat output. In particular, the heat output can be adjusted based on the flow rate through the housing.

[0011] The heating unit can heat flow rates from 0.18 m³ / h. Furthermore, flow rates up to at least 3.3 m³ / h can be heated.

[0012] The heating unit can have a length of 260 - 280mm and a diameter of between 70 and 90mm.

[0013] The invention also relates to a domestic appliance with a heat pump, which has a flow line and a domestic appliance heating unit as described above in the flow line of the heat pump. The heating unit can thus reheat the water flowing through the flow line of the heat pump.

[0014] The heating flange optionally features three primary tubular heaters, each with a power output of 1 kW, and three secondary tubular heaters, each with a power output of 2 kW. The three tubular heaters can be switched independently of each other. With these six tubular heaters, the electrical power of the heating unit can be switched in 1 kW increments from 1 kW to 9 kW using the appropriate circuit.

[0015] Further embodiments of the invention are the subject of the subclaims.

[0016] Advantages and embodiments of the invention are explained in more detail below with reference to the drawings. Fig. 1 shows a schematic representation of a domestic appliance heating unit, Fig. 2 shows a schematic representation of a heating flange, Fig. 3 shows a perspective and schematic representation of a heating flange, and Fig. 4 shows a schematic sectional view of a heating flange.

[0017] Fig. 1 shows a schematic representation of a heating unit. The domestic heating unit 100 has a (plastic) housing 110 with an inlet 111 and an outlet 112. A heating flange 200 can be placed into the essentially cylindrical (plastic) housing or cylindrical shell, which can heat the water located within the housing 110. The heating unit 100 has a (plastic) housing 110 with a shell 115, a lower end 113, and an upper open end 114.

[0018] The heating flange 200 can be held at the upper open end 114 by means of a locking ring 120 and thus the housing 110 can be closed.

[0019] Fig. 2 shows a schematic representation of a heating flange. The heating flange 200 has a flange plate 240, optionally a protective tube for a temperature limiter 250, a grounding contact 260, first tubular heating elements 270, and second tubular heating elements 280.

[0020] The first tubular heaters 270 can, for example, have a power output of 1 kW. The second tubular heaters 280 can have an electrical power output of 2 kW.

[0021] According to one example, the heating flange 240 can have three first tubular heaters 270 and three second tubular heaters 280. The first and second tubular heaters 270, 280 are arranged within the heating flange 200 such that they can each be individually electrically contacted. Thus, the total heating output of the heating flange 200 can be very finely controlled by appropriately contacting the first and second tubular heaters 270, 280. In particular, the total electrical output of the heating unit can be controlled in 1 kW increments.

[0022] Fig. 3 shows a perspective and schematic representation of a heating flange. In Fig. 2 An upper end 114 of the housing 100, a sealing ring 300, a heating flange 200, and a locking ring 120 are shown. The locking ring can be used to hold the heating flange 200, after it has been placed within the housing 110, by screwing the locking ring 120.

[0023] The invention relates to a heating cartridge with a plastic housing. A heating unit, for example in the form of a heating flange, can be provided in the heating cartridge. The heating flange comprises a flange plate and several independently controllable tubular heating elements. An O-ring or a multi-component injection-molded part, for example, can be used to seal the flange plate against the base body or the housing. A locking ring can be placed on the open end of the housing to secure the inserted heating flange. This allows for simple and replaceable assembly.

[0024] Optionally, the locking ring can be designed as a bayonet lock or a screw connection. This is particularly advantageous because it allows for easy replacement of a heating unit. Furthermore, it is advantageous because the heating unit is easier and more easily manufactured. The heating unit simply needs to be placed in the housing and then secured using the locking ring.

[0025] The housing 110 has an inlet 111 and an outlet 112, a base 130, and an open end 114. The inlet and the outlet 112 can be arranged laterally on the housing 110. The heating flange 200 can, for example, have three first and three second tubular heaters, wherein the first tubular heaters can have an electrical output of 1 kW and the second tubular heaters can have an electrical output of 2 kW. The first and second tubular heaters can be controlled separately from one another, so that the total output of the heating unit can be adjusted very variably, particularly in 1 kW increments.

[0026] The adjustable electrical output of the heating unit is advantageous because it allows for controlled heating of different flow rates. In particular, fine-tuned control of the total heating output can make it possible to keep the flow temperature constant at varying flow rates. High outputs of, for example, 9 kW can be delivered down to low flow rates of 0.5 m³ / h or less.

[0027] The housing 110 can have a height of between 250 and 300 mm, preferably 277 mm. The diameter of the housing 110 is between 60 and 80 mm, preferably 74 mm.

[0028] The three first radiators 270 can have an electrical output of 1 kW, and the three second radiators 280 can have a heating output of 2 kW. The radiators can be electrically coupled to each other in such a way that, with a three-phase connection, symmetrical phase loads are created at specific power levels. Each radiator can be controlled individually, allowing a heating output gradation of 1 kW.

[0029] According to one aspect of the present invention, a domestic appliance, in particular a heat pump, is provided with a heating unit as described above. The heating unit is arranged in particular in the flow line of the domestic appliance, in particular the heat pump, in order to increase the temperature in the flow line. Thus, the heating unit can also be used in continuous operation for hot water and heating water in a domestic appliance. The heating unit has a flange plate with six electrical connections for six tubular heating elements, a grounding contact, and a protective tube for a temperature limiter.

[0030] Fig. 4 shows a schematic cross-section of a heating unit. The heating unit 100 has a housing 110 with a shell 115, a lower end 113, and an upper open end 114. The heating flange 200 is placed in the open end 114 with the flange plate 240 and sealed to the housing 110 by means of the gasket 300.

[0031] The housing 110 is preferably substantially cylindrical (i.e., in particular, the casing shell is cylindrical). The base 113 can be partially spherical. The upper end 114 of the housing 110 is open, and a heating flange can be inserted into the open end.

[0032] The heating unit according to the invention is advantageous because it allows for a compact design with high electrical power. In particular, the ratio between the power and the volume of the heating cartridge is high.

[0033] Optionally, the housing and the connectors can be made of plastic.

[0034] The heating unit or heating cartridge is used in particular for a heat pump.

[0035] According to one aspect of the present invention, the heating unit comprises a plastic housing and a heating flange, for example, a copper heating flange. After being inserted into the plastic housing, the heating flange is locked by twisting a locking ring (for example, in the form of a bayonet lock). The inlet and outlet can be positioned laterally, allowing plug-in assembly according to the inlets and outlets. Optionally, these plug-in connections can be locked using a clamp. The heating flange can have six individual heating elements, which can have different electrical outputs. This enables a compact heating unit with individual heating elements, which can provide finely adjustable electrical output, thus enabling heating even smaller volume flows.

[0036] The radiators of the heating flange are arranged in such a way that low-loss airflow is achieved around all radiators. In particular, good heat transfer is ensured at all operating points. The heated length and surface load of the radiators can be adjusted to the expected flow rates.

[0037] The radiators, or rather their heating output, can be configured in two groups of three identical radiators, each consisting of three identical radiators. A star connection achieves a three-stage power output with symmetrical phase loading. Optionally, a further asymmetrical connection can be enabled using a single-, two-, and three-phase supply.

[0038] Optionally, a safety temperature limiter can be mounted in or on the flange plate to measure and reliably limit the outlet temperature. The temperature measuring point is positioned at the outlet between the radiators and ensures robust shutdown at all operating points, even in the absence of flow.

[0039] The base body can be designed in such a way that the following development steps of the heating flange can be achieved through different variants and alternative designs. List of reference symbols

[0040] 100 Building services heating unit 110 Housing 111 Inlet 112 Outlet 113 Lower end 114 Upper end 115 Shell 120 Locking ring 130 Base 200 Heating flange 240 Flange plate 250 Temperature limiter 260 Earthing contact 270 First tubular heater 280 Second tubular heater 300 Sealing ring

Claims

1. Domestic appliance heating unit (100), comprising a plastic housing (110) with an inlet (111), an outlet (112) and an open upper end (114), and a heating flange (200) which can be inserted into the plastic housing (110) through the open upper end (114) and can be fastened in or on the open end (114) of the plastic housing (110) by means of a locking ring (120).

2. Domestic appliance heating unit (100) according to claim 1, wherein the heating flange (200) comprises a flange plate (240), a plurality of first heating elements (270) and a plurality of second heating elements (280), wherein the first and second heating elements (270, 280) are electrically controllable independently of one another, wherein the flange plate (240) is releasably fastened to the upper end (114) of the plastic housing (110) by means of the locking ring (120).

3. Domestic appliance heating unit according to claim 1 or 2, wherein the first heating elements (270) have an electrical power of 1 kW and the second heating elements (280) have an electrical power of 2 kW.

4. Domestic appliance heating unit (100) according to one of claims 1 to 3, wherein the plastic housing (110) has a cylindrical shell (115), wherein the inlet (111) and the outlet (112) are provided in the cylindrical shell (115).

5. Domestic appliance, comprising a heat pump and a domestic appliance heating unit (100) in a flow line of the heat pump.

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