Patent Application
20120288383
This application claims the benefit of priority under 35 U.S.C. ยง119 of German Patent Application DE 10 2011 075 476.8 filed May 9, 2011, the entire contents of which are incorporated herein by reference.
The present invention pertains to an air feed blower, especially for a vehicle heater, comprising an electrically driven blower drive motor as well as an air feed wheel that can be driven by the blower drive motor.
Such air feed blowers, generally also called side duct blowers, are frequently used in vehicle heaters in order to feed to a combustion chamber combustion air, which forms a combustible air-fuel mixture with a fuel evaporated towards the combustion chamber, wherein the thermal energy made available during the combustion of this mixture is transferred, for example, at a heat exchanger to air being fed into the interior space of a space for heating this interior space.
Such air feed blowers used in vehicle heaters are subject to considerable temperature fluctuations due to their operation, especially at low outside temperatures. These may adversely affect especially the electric contacting, which is embodied, in general, by soldered or plug-type connections, so that no reliable contacting can be guaranteed as a result. Vibrations occurring during the operation of the vehicle heater or vehicle may likewise have an adverse effect on the electrical contacting of the blower drive motor.
An object of the present invention is to provide an air feed blower, which has a more reliable electric contacting of the blower drive motor compared to conventional air feed blowers.
This object is accomplished according to the present invention by an air feed blower, especially for a vehicle heater, comprising an electrically driven blower drive motor as well as an air feed wheel, which can be driven by the blower drive motor, wherein said blower drive motor is contacted electrically with the use of spring contacts.
The use of spring contacts makes it possible, on the one hand, to effectively compensate the stresses, which are due to temperature fluctuations and act on the electric contacts, by the spring force exerted by the spring contacts, and, on the other hand, to effectively absorb the vibrations occurring during the operation of the blower drive motor. The known drawbacks of the conventional contacting can thus be avoided, as a result of which more reliable operation of an air feed blower is, on the whole, ensured.
The design of the air feed blower may be such that an air feed duct, which extends in a ring-shaped pattern about an axis of rotation and is open on an axial side covered by the air feed wheel with an inlet area and with an outlet area separated by an interrupter area from the inlet area, is provided in a blower housing connected to the blower drive motor, wherein an opening, through which passes a drive shaft of the blower drive motor, which said shaft is connected to the air feed wheel for joint rotation, is provided in the blower housing.
Provisions may be made in a preferred embodiment for insert pins to be received by the spring contacts to be provided in association with the spring contacts for the electric contacting.
The spring contacts may be designed in this case, for example, as leaf springs, which are in contact with the insert pins over a large area in the contacted state in which the insert pins are received, as a result of which reliable electric contact is established, on the one hand, and the mechanical fastening means that are otherwise necessary in case of the use of, for example, spring contact pins, are eliminated, on the other hand. Even though a plurality of electrically conductive materials can be used, in principle, for spring contacts designed for use with insert pins, which spring contacts are designed, for example, as leaf springs, the use of leaf springs and insert pins made of metal is advantageous especially in respect to high mechanical stability.
The design may, furthermore, be such that a control device is provided in association with the blower drive motor. The use of a control device makes it possible to coordinate the operation of the blower drive motor with the operation of other system areas, for example, the combustion chamber area, whose temperature is, in general, an essential parameter for the operation or for the actuation of the air feed blower.
Provisions may be made in a preferred embodiment for the control device to be arranged in the area of the blower drive motor. Such a measure makes possible a compact design of an air feed blower. It is now possible, for example, to consider accommodating the control device and blower drive motor in a common housing or providing fastening means, which permit the corresponding housing parts of the control device and of the blower drive motor to be assembled into a single housing in a simple manner. Moreover, no connection lines between the control device and blower drive motor, which are long in relation to the dimensions of the air feed blower, are needed in such a design, so that corresponding means for staying or fastening the connection lines can be eliminated, as a result of which the design is, on the whole, simplified.
To make it possible to do away with connection lines between the control device and blower drive motor altogether, the design may be such that fastening means comprising the spring contacts are provided in the area of the blower drive motor to arrange the control device. Furthermore, provisions may now be made for the control device to be fastened to the blower drive motor with the use of the insert pins received in the spring contacts.
The spring contacts may now be formed, for example, from two leaf springs, which have a distance from each other that is shorter than the thickness of the insert pins. By inserting the insert pins into the spring contacts, the two leaf springs are pushed apart, so that a mechanically stable, frictionally engaged connection develops between the insert pin and spring contact based on the now acting restoring force of the leaf springs.
There is, in principle, no restriction regarding the arrangement of the insert pins and spring contacts at the blower drive motor and at the control device. For example, a mechanical connection can thus be established between the control device and blower drive motor by arranging at the control device and at the blower drive motor an insert pin and a spring contact each at equal distances in corresponding positions for a certain arrangement of the control device relative to the blower drive motor. However, since it is, in principle, simpler to arrange the insert pins instead of the spring contacts at the control device, for example, by soldering into a control printed circuit board, a design in which the spring contacts are arranged at the blower drive motor and the insert pins at the control device is preferred.
There are, in principle, very many possibilities for the exact arrangement of the insert pins and spring contacts. However, it is advantageous concerning simple mounting of the control device on the blower drive motor if the control device can be fastened to the blower drive motor by a motion that is essentially at right angles or in parallel relative to the axis of rotation.
The present invention also pertains to a vehicle heater comprising an air feed blower according to the present invention.
The present invention will be explained in more detail below with reference to the two attached drawings. The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which preferred embodiments of the invention are illustrated.
Referring to the drawings in particular,
An air feed duct 22, which extends essentially in a ring-shaped pattern about the axis of rotation A and which is open towards an axial side facing the air feed wheel 16, is formed in a blower housing 20 connected to blower drive motor 14. Air feed wheel 16 has a ring-like recess 17, which corresponds to and is located opposite the air feed duct 22 and in which a plurality of feed blades following each other in the circumferential direction are arranged. An inlet area leading to air feed duct 22, an outlet area leading away from air feed duct 22, as well as an interruption area separating these areas are not shown in
The air feed blower 10 shown in
To control the operation of the blower drive motor 14 as well as also for coordination with the operation of other system areas, a control device 26 is provided in this exemplary embodiment, which comprises essentially a housing 28, a control printed circuit board 30 as well as two insert pins 32 arranged at the control printed circuit board 30. As is apparent from the cross-sectional view in
To fasten the control device 26 to the combustion chamber 14, end sections of the insert pins 32 are received in spring contacts 34, which are accessible, as is apparent from
The arrangement of the insert pins 32 as well as of the corresponding spring contacts 34 in a plane extending at right angles to the drive shaft, as in the embodiment shown in
Another embodiment of an air feed blower according to the present invention will be described below on the basis of
Components that are identical or functionally identical to those in
The electric contacting of a blower drive motor 114 is likewise performed with the use of spring contacts 134 comprising leaf springs 136 as well as insert pins 132 received in same in the air feed blower 110 shown in
The two embodiments in
The fastening of the control device 26, 126 being described here by means of the insert pins 32, 132 received in the spring contacts 34, 134 represents a very simple possibility of fastening. However, it shall not, in principle, be ruled out hereby that additional fastening means, for example, ones comprising screw connections may be provided, especially if an especially stable fastening of the control device is desirable.
While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2011 075 476.8 | May 2011 | DE | national |
