Temperature determination through a transmitter and on the controller board integrated temperature sensor

The invention relates to a heater, particularly with liquid fuel powered water or air heater of a Motor vehicle in the form of a supplementary heater or an auxiliary heater, with a housing shell and a heat exchanger, and with an electronic control unit for regulating or Monitoring the heating operation with the aid of at least one temperature sensor, in particular control temperature sensor and / or Overheating sensor.

In vehicle heaters of the aforementioned type is for Room temperature control, a temperature sensor in the form of a control temperature sensor used preferably in the air or arranged water guide channel in the region of the heat exchanger and actual value of a control loop. The control unit controls the heat output in such a way that the room temperature the predetermined desired value in lower tracking error equivalent. Another temperature sensor in the form of a Overheating sensor which, at a suitable point in the hot heater Kalottenbereich particularly in a heat exchanger, is, used for upper temperature limit of the heater by turning off the heater to an overheating condition exclude in the heater.

Such a vehicle heating device, for example, from DE 44 46 829 A1. A disadvantage is that the control temperature sensor and the overheating sensor as separate components with prefabricated longer cables, contacts and individual wire seals are individually ordered and supplied to the mounting, are mounted and held by separate components. Both Sensors are identical components and can at the control module connector be reversed. In order to regulate the heating power and safety against overheating and a burnout to ensure the heat exchanger is the reliable contact the separate temperature sensors on the heat exchanger surface particular importance. The sensor in question must be followed by "movements" and thermal expansions. The efficiency of the known system is fundamentally very well, the cost of production, however, are relatively high.

Starting from the aforementioned prior art, the object the invention, a heating apparatus of the kind mentioned eingahgs further develop that quickly, easily and securely mounted can be, is reliable in operation and in particular accompanied by little manufacturing effort.

the invention of the underlying object is achieved by a heater that specified in the independent claim 1.

the heater is advantageously developed by the features the dependent claims 2 to 17th

Essence of the invention is that the in the area of ​​ECU board the control unit arranged at the control unit board connected temperature sensor, a high-heat-conductive Temperature-transfer element, a so-called transmitter, contacted which or for its part, by an opening of the housing shell, in particular the water jacket, extends toward the heat exchanger. Instead of a separate Temperature sensor according to the prior art according to the invention a far more cost effective unempfindlicheres Transmission element, namely the "transmitter", as a probe to used in the temperature range to be measured of the heater penetrate, said at a water heater of Transmitter is preferably dipped in hot water and / or contacted with the heat exchanger surface. At this Transmitter engages the positioned on the ECU board Temperature sensor from the temperatures. The temperature sensor is preferably as a component on the circuit board of the Control unit or the control unit PCB soldered. consequently can be obtained by the invention to separate consuming temperature sensor be waived. A typical applicant for heaters "Direct" detection of the heat exchanger surface temperature is still possible. The invention is for all air and water heaters of any performance class, in particular in motor vehicles.

A temperature sensor can already in ECU production set on the control unit board and prefabricated ECU board along with temperature sensor connected easy on the heater and quickly with a positioned Transmitter final assembly. As positioning aid serves here the opening in the housing jacket.

Preferably, the underside of the temperature sensor contacting Transmitter slidably in the fitting opening formed opening of the housing jacket added. This fine positioning of the transmitter is possible. In addition, the extension depth of the transmitter can towards Heat exchangers are optionally set exactly.

The transmitter preferably includes a Paßgehäuseteil with a peripheral recess, wherein the outer periphery of Paßgehäuseteils directly in a sliding seat in the fitting opening is received or indirectly. This is the insertion the transmitter simplifies the fitting hole and jamming or tilting minimized.

Preferably located in the peripheral recess, a sealing ring, good for a sealing of the run in the heater the medium to air or water, provides.

A particularly advantageous embodiment provides that only the heat insulating seal the fitting opening as formed opening of the housing jacket contacted, and not the transmitter of a highly thermally conductive member is. In this way does not get heat by conduction in the adjacent housing jacket, but remains in the Transmitter.

Another embodiment provides that the temperature sensor together with transmitter across an in-controller Compression spring supported on a protective housing of the control device are. When installed, the transmitter and temperature sensor so as to ensure that, for example, by temperature fluctuations Expansions caused (movements) of Heat exchanger without damaging the transmitter, the temperature sensor, absorbs the controller or the heat exchanger can be.

Preferably, the housing casing in axial extension of the Fitting opening at least one remote from the fitting opening, radially outwardly directed projection, on which the control device board supported area. This results a rich, stable support for ECU board. also the control device board in a distance from the housing casing preferably be arranged parallel to the axis. Of the Distance creates a thermally insulating air gap between Housing jacket and ECU board.

The transmitter has, in particular substantially cylindrical shape on.

The ECU board is preferably releasably or on the placed flat against the projections and these projections supported.

In particular, the top of the ECU board is in a distance from the protective housing arranged an installation space to provide for electronic components, which preferably attached to the top of the ECU board and connected are.

The temperature sensor is an integrated component with preference the ECU board, which at the ECU board connection herstellend infected, soldered or otherwise is attached. A possible connection cable can thereby a have short length. Individual wire seals omitted.

The transmitter can be connected to a radially inner stop of Heater spring biased by the force of the compression spring be. The radially inner stopper, a paragraph or a be tapering in the opening of the housing jacket.

However, particularly preferred the radially inner stop a Lateral surface of the heat exchanger itself, in particular, a contact surface of the temperature sensor, the temperature of is to be monitored. This is a safe, free of play and voltage-free contact of the transmitter and the temperature sensor made to the heat exchanger with simple means, and without the risk of damage to the sensor and the transmitter in operation due to possible temperature fluctuations or thermal expansions.

The temperature sensor may be a single sensor, in particular an overheating temperature sensor or a temperature sensor rule, wherein at a single control device board several arranged spaced-apart temperature sensors could be. Each temperature sensor is then a separate assigned transmitter.

Preferably, the temperature sensor is a combination sensor, which the overheating sensor and the control temperature sensor contains as a structural unit, which has advantages in manufacture and in brings the assembly with it. Overheating sensor and control temperature sensor can then also not interchanged during assembly will. Overheating sensor and control temperature sensor have their own transmitter.

The protective housing itself is resistant and waterproof to the housing casing connected, in particular screwed.

The invention is described using an exemplary embodiment detail with reference to the accompanying drawings explained.

In Figure 1, the single drawing is shown schematically in a axial vertical section of the upper right portion of a heater illustrated.

The heater is in particular a powered with liquid fuel Water heater 20 of a motor vehicle in the form a heater and has among others a housing shell 1 in the form of a water jacket, a heat exchanger 2 and a control unit 11 for regulating or monitoring the Heating operation with the aid of a temperature sensor 3rd

The temperature sensor 3 is the side of a control device board 4 of the control unit 11, and the ECU board via cable positioned soldered. Of the Temperature probe 3 extends according to drawing down, said directly to the bottom of the temperature sensor 3 a highly thermally conductive heat-transfer element, a so-called Transmitter 10, contacting and connecting through an opening 6 of the casing shell 1 in the direction of heat exchanger 2 extends.

The connected to the underside of the temperature sensor 3 Transmitter 10 is movable in the fitting hole formed as Opening 6 of the casing shell 1 was added.

The transmitter 10 has a Paßgehäuseteil with a circumferential recess , whereby the outer periphery of the Paßgehäuseteils received in a sliding seat in the fitting opening can be. In the peripheral recess, a sealing ring 12 is received, is what designed so that in the embodiment the drawing only the sealing ring 12 the housing shell 1 contact in the fitting hole.

The transmitter 10 and the temperature sensor 3 are connected via a in the control device 11 located compression spring 7 in a protective housing 8 of the control device 11 is supported. For this purpose, a corresponding Fitting recess in a built in protective housing 8 Projection 13 for positive location of the upper Axial end of the pressure spring 7 is provided.

The housing shell 1 has in axial extension of the fitting opening two remote from the fitting opening, radially outward spaced projections 9 on which the is ECU board 4 attached and supported extensively.

The top of the ECU board 4 is located in a Distance to the protective housing 8. At the top of the ECU board 4 are diverse here unspecified interest electronic components mounted and connected. 5

The transmitter 10 is at a radially inner stop of Heater spring biased by the force of the compression spring. 7 The radially inner stop is in particular a lateral surface of the heat exchanger 2. The envelope surface is a radially raised contact surface for the transmitter 10, the Temperature must be monitored.

The protective housing is 8 and waterproof to the housing casing 1 screwed.

Obviously, the aforementioned water heater 20 can be easily, quickly and safely assemble and particularly cost finished.

The temperature sensor 3 is already in ECU production fitted on the control unit board 4 and connected. Further, in prefabrication of ECU board the electronic components placed and connected. 5

Then, via the transmitter 10, the sealing ring 12 in the associated slipped peripheral recess, and the transmitter 10 including sealing ring 12 in the radial fitting opening of the housing jacket 1 used. The foremost lowermost according to drawing End of the transmitter 10 touches here the radial A step ahead of the jacket of the heat exchanger 2. Then the prefabricated controller board 4 on the projections 9 inserted, in which case the temperature sensor 3, the axial upper Side of the transmitter 10 contacted. The temperature sensor 3 and the preferably cylindrical transmitter 10 are in this case axially aligned to each other. Following this, is in axial alignment with the two above-mentioned components, the Compression spring 7 fitted to the temperature sensor 3rd After all the protective housing 8 is mounted on the casing jacket 1 in such a way that the top in the form of recess in the projection 13 End of the compression spring 7 engages. The protective housing 8 is and waterproof screwed to the housing jacket. After screwing the compression spring 7 spring biased in a manner that one part of the transmitter 10 sure the heat exchanger 2 and on the other hand, the transmitter 10 on certain Temperature sensor 3 is applied, however, transmitter 10 and temperature sensor 3 radially can yield outwardly when increased Voltages are applied. Also the axial alignment is then the compression spring 7, the temperature sensor 3 and the transmitter 10 ensured. An axial displacement of the aforementioned Components optionally by the connecting cable of Temperature sensor 3 offset, which for ECU board 4 leads.