NO20140329A1 - Connection element for engine heater - Google Patents

Abstract

A heating device for heating a fluid, especially in a vehicle or vessel, includes at least one heating element (7) arranged in a housing (1) having a fluid inlet (4a) and a fluid outlet (4b). The fluid inlet and the fluid outlet are connected via one or more fluid channels (6a, b) in thermal communication with the heating element (7). At least one of the fluid inlet and fluid outlet comprises a detachable connector (18; 18 ') having the first end with means (21, 22, 34) for releasable connection to the housing (1) and a second, free end (19) adapted connection to a hose and / or component. The housing is of a thermally conductive material and the connector is of a thermally insulating material.

Description

Connection element for engine heater

Field of the invention

The invention relates to heating devices, in particular for use to heat a unit in a vehicle or vessel. More specifically, the invention relates to a connection element for an engine heater.

The background of the invention

Heating devices for engines for various types of vehicles or vessels are well known. The purpose of these is to preheat the engine by direct or indirect heating of the engine's oil or coolant, so that it starts more easily in cold weather, and will reduce fuel consumption / exhaust gases related to cold starting of the engine. Corresponding heating devices for other mechanical units in a vehicle or vessel, such as a gearbox, hydraulic system, transmission system, are also known. For the sake of simplicity, the term "engine heater" will mainly be used in what follows, although these can also be used for heating other components.

There are different types of engine heaters, including those that heat the engine's coolant. A variant of such engine heaters comprises a container which has a heating element in it. The container has an inlet opening and an outlet opening so that the engine coolant hose can be cut and the hose ends connected to these openings. The engine heater is thus part of the engine's cooling circuit, and the coolant that flows through the container is heated by the heating element and circulates in the engine's cooling circuit. An engine heater of this type is often referred to as a "hose heater".

EP 1 793 103 A describes an engine heater with a container with a thermostatically controlled, electric, heating element and connection pieces for coolant inlet and outlet.

EP 2 462 339 Al also describes an engine heater with such a container with connecting pieces for hoses, where the heating element is a PTC element ("Positive Temperature Coefficient").

US 5,408,960 describes an engine heater with a container with an electric, thermostatically controlled, heating element and a pump that drives the coolant in the cooling circuit. The container has connections for coolant inlet and outlet.

Engine heaters with other types of heating elements are also known.

The known engine heaters of this type have in common that their connection pieces for the inlet and outlet respectively are adapted to the hoses to which they are to be connected.

Figure 1 shows an engine heater 51 of a known type, comprising a container 52 (which houses a heating element; not shown), an electrical contact 53 (for power supply to the heating element), as well as an inlet connection 56 and an outlet connection 55 for coolant. The spigots are smooth pipe spigots (also often referred to as "nipples") provided with a respective flange 57, 54 at their outer ends. During installation, the cooling system's rubber hoses are fed in over the respective flanges and secured with hose clamps (not shown) or similar fasteners. The flange ensures that the fasteners, and thus the hoses, do not accidentally slip off the spigot. The engine heater may also include attachment devices (not shown) so that it can be attached to the engine or another component.

An engine heater can only be inserted into a cooling system if it does not compromise the cooling circuit. The engine heater itself must of course be tight and dimensioned for the pressures and temperatures it may be exposed to. It is equally important that the connections between the engine heater and the cooling system hoses are completely tight. This is achieved by adapting the engine heater's inlet and outlet nozzles already in the design and production process to the cooling hose construction (including hose quality and diameter) of the engine for which it is designed. There are several hose dimensions on the market today, and some car and/or engine manufacturers have started to design in special hoses and pipes. Different types of engine heaters must therefore be manufactured, adapted to the individual engine's hoses.

The engine compartment in modern cars is often very compact and narrow, so that there is little space to place and install an engine heater when it is to be fitted into the existing cooling circuit. In such tight surroundings, it can be difficult to ensure that connected components are installed securely and correctly, such as at the right angle and in the right place in the cooling circuit. It is not unusual, for example, for the fitter to cut and remove a too short length of the cooling hose when the engine heater is installed, which can cause the remaining cooling hose to bend and thus limit the fluid flow after the engine heater has been installed.

The invention produces solutions which remedy at least some of the weaknesses of the known technique, and in addition has further advantages.

Summary of the invention

The invention is described and characterized in the independent claim, while the non-independent claims express other characteristics of the invention.

A heating device has been developed for heating a fluid, particularly in a vehicle or vessel, including at least one heating element arranged in a housing with a fluid inlet and a fluid outlet; where the fluid inlet and the fluid outlet are connected via one or more fluid channels in thermal connection with the heating element; characterized in that at least one of the fluid inlet and the fluid outlet comprises a removable connecting piece which has a first end with means for releasable connection to the housing and a second, free, end adapted connection to a hose and/or a component.

In one embodiment, the heating device includes an intermediate piece assigned to the housing at the fluid inlet or fluid outlet and includes connecting means for connecting to the aforementioned first end of the connecting piece. In one embodiment, the intermediate piece is releasably assigned to the housing.

The housing is preferably made of a heat-conducting material and the connecting piece is preferably made of a thermally insulating material.

In one embodiment, the connecting piece is rotatably connected to the housing.

An advantage of the invention is that the heating device can be configured with different exchangeable connection pieces. The replaceable connectors will be configurable when installing the heating device (e.g. shipping with many more connectors than strictly necessary), or this can be configured from the factory. The connection sockets can be specific to the car manufacturer, i.e. they fit right into the manufacturer's quick coupling (on the engine) at one end, and the engine heater at the other end.

Brief description of the drawings

The above and other characteristics of the invention will be clarified in the following description of preferred embodiments, given as non-limiting examples, with reference to the attached drawings in which: Figure 1 is an illustration of an engine heater of a known type; Figure 2 is a perspective drawing of an embodiment of the heating device according to the invention; Figure 3 is a perspective drawing of the heating device shown in Figure 2, seen from mainly one end; Figure 4 is a perspective drawing of the heating device shown in Figure 2, fitted with removable connecting pieces according to the invention; Figure 5 shows a vertical section along the longitudinal axis C in Figure 4; Figure 6 is an enlargement of part D in Figure 5, seen from another perspective; Figure 7 is a perspective drawing of an exchangeable socket according to the invention; Figure 8 is a perspective drawing of a second embodiment of the replaceable spigot according to the invention, in the mounted state on an intermediate piece; Figure 9 is a sectional drawing (longitudinal section) of the connecting piece shown in Figure 8; Figure 10 corresponds to Figure 8, but shows the spigot in a connected, unlocked state, where the locking element has been removed;

Figure 11 is a perspective drawing of the intermediate piece; and

Figure 12 is a perspective drawing of the detachable connecting piece shown in Figures 8-10.

Detailed description of preferred embodiments

In this description there are terms such as "upper", "lower", "inner", "outer", "vertical", "horizontal", "front", "rear", etc. The terms are used with reference to the device according to the invention , as it appears in the figures.

Figure 2 shows an embodiment of the heating device according to the invention, in a state where the replaceable connectors are not mounted. A mainly tubular housing 1 has a first fluid opening 4a and a second fluid opening 4b and internal channels which allow fluid flow between the fluid openings. Each of the fluid openings can be connected to respective hoses (not shown) via replaceable connection pieces in a manner described below, so that the heating device is an integral part of, for example, a coolant circuit in an internal combustion engine. It should be understood that fluid can flow either one way or the other through the housing. Which of the fluid openings 4a,b is the inlet opening and the outlet opening, respectively, therefore depends on the actual application of the heating device and is of no importance to the invention as such. The housing 1 is preferably made of a material with good thermal conductivity. A suitable material in this respect is aluminium.

In the illustrated embodiment, the housing 1 has a substantially circular cross-section, and has a base 17 to which a cover 2 is attached, in a manner known per se, e.g. by means of screws 8 through a flange 9 on the cover. The figure also shows a gasket 10 between the flange 9 and the base 17.1 the cover, there is also a contact 3 for connection to electrical cables (not shown) in a connection room 27 (see figure 5) for further connection to a heating element 7 (see figure 5). The contact 3 is arranged along the longitudinal axis of the house, which is advantageous from an installation and user perspective.

Figure 3 shows that in the housing, between the fluid openings 4a,b, there are two separate fluid passages 6a,b. Each fluid passage 6a,b is defined by a respective internal part of the housing wall (which in the illustrated embodiment is circular arc-shaped) and a respective internal partition wall (only the partition wall 12b shown in figure 3) which in the illustrated embodiment extends between an upper part in the house and a lower part of the house. Between the partitions there is a chamber 13 (see also figure 5). The partition walls are connected at the front and rear with respective end walls 5a. The end walls 5a are preferably rounded or streamlined to reduce fluid resistance and accompanying pressure loss when fluid flows through the housing.

Figure 4 shows the heating device as illustrated in Figure 2, but here fitted with an embodiment of removable and replaceable connection pieces 18. The connection pieces have respective flanges 19 at their free ends, which can be connected to the cooling system's hoses. An advantage of such replaceable connection pieces is that the free ends can be dimensioned and designed so that they fit different hose dimensions and/or connections (i.e. the flanges 19 can be replaced by other geometries or connection mechanisms, such as quick connectors). The same heating device can thus be used together with different hose systems, e.g. with manufacturer-specific dimensions and/or connections, only by changing the connection plugs 18. Figure 5 shows that the heating device a chamber 13 which is adapted to receive a heating element 7, in the illustrated embodiment a so-called PTC element. PTC elements ("Positive Temperature Coefficient" are well known as such and therefore do not need to be described in detail here. It should be understood that other heating elements (possibly in combination with a thermostat) can be used. The PTC element 7 is connected to contact 3 via wires (not shown) The connecting pieces 18 have respective internal channels 29 so that a fluid channel connection is formed with the above-mentioned fluid openings 4a,b. Figure 6 shows how the connecting piece 18 is mounted to the housing 1.1 the illustrated embodiment, the connecting piece has an annular flange 22 and an o-ring 21 placed in a groove 34 on the spigot. The O-ring seals against the inner wall of the fluid opening 4a and a locking ring 20 holds the connecting spigot 18 in place in the axial direction. The connecting spigot is thus rotatably attached to the housing.

Figure 7 shows the connection socket 18, disconnected from the heating device.

A further embodiment of the connection socket 18' according to the invention will now be described with reference to figures 8-12.

In this embodiment, the connecting piece 18' is angled so that the internal fluid channel 29' has a change of direction of 90° in relation to the fluid opening 4a'

The connecting piece 18' is connected to an intermediate piece 30 and is held in place by a flexible clip 28. In the embodiment shown, the intermediate piece 30 is designed with an end 31 for mounting in a housing on a heating device (not shown in figure 8). It should be understood that the intermediate piece 30 can be a separate part as shown in figures 8-11, or it can be permanently integrated with (ie a part of) the housing of the heating device.

The connecting piece 18' is held in place in the intermediate piece 30 by the clip 28 going through slots 32 in the intermediate piece and into a groove 34' which is defined by two raised ring parts 33. The connecting piece is thereby attached to the intermediate piece 30 - and thus to the housing of the heating device. In the embodiment shown, the connecting piece is rotatable about the longitudinal axis C. An o-ring 21 provides a seal between the connecting piece 18' and the intermediate piece 30.

It should be understood that the connection spigot according to the invention can have other angles than those shown here. The connection spigot can be given any suitable geometric shape, adapted to the relevant area of use. The connecting piece can also have a length that makes hoses redundant, i.e. the connecting piece can be connected directly to the next component in the cooling circuit. The connecting piece according to the invention is preferably made of a thermally insulating material, such as thermoplastic material (e.g. PPS, PP A).

Although the invention is described with reference to an engine heater for a coolant in an internal combustion engine, it should be understood that it is applicable for assembly on other units, particularly in a vehicle or vessel, and for other fluids (gases and/or liquids) than coolant .

Although the invention is described with reference to a house with a circular cross-section, it should be understood that the removable connecting pieces can be used on houses with other cross-sections. Nor should the invention be limited to a heating device that uses PTC elements.

Claims (5)

1. Heating device for heating a fluid, particularly in a vehicle or vessel, including at least one heating element (7) arranged in a housing (1) with a fluid inlet (4a) and a fluid outlet (4b); where the fluid inlet and the fluid outlet are connected via one or more fluid channels (6a,b) in thermal connection with the heating element (7); characterized in that at least one of the fluid inlet and the fluid outlet comprises a removable connecting piece (18; 18') which has a first end with means (21, 22, 34) for releasable connection to the housing (1) and a second, free, end (19) adapted for connection to a hose and/or a component. 2. Heating device according to claim 1, further including an intermediate piece (30) assigned to the housing at the fluid inlet or fluid outlet and including connection means (28, 32) for connection to the aforementioned first end of the connection spigot. 3. Heating device according to claim 2, where an intermediate piece (30) is releasably assigned to the housing. 4. Heating device according to any one of claims 1-3, where the housing (1) is made of a heat-conducting material and the connecting piece (18) is made of a thermally insulating material. 5. Heating device according to any one of claims 1-4, where the connecting piece is rotatably connected to the housing.