WO1979001148A1

WO1979001148A1 - Hot air hand operated apparatus for defrosting car window panes

Info

Publication number: WO1979001148A1
Application number: PCT/DE1979/000052
Authority: WO
Inventors: W Landsrath
Original assignee: Landsrath Walter
Priority date: 1978-05-30
Filing date: 1979-05-30
Publication date: 1979-12-27

Abstract

The hot air manual apparatus for defrosting car window comprises a plurality of elongated flow channels (6, 7, 8) extending into the outlet nozzle (2) up to the outlet mouth thereof (3, 4, 5) shaped like slots, these outlet mouths (3, 4, 5) being spaced one from the other; heating elements (9) are arranged on the walls of the channels (6, 7, 8). The flow channels (6, 7, 8) and/or the heating elements thereof (9) may be designed so as to obtain a higher temperature of air blown into the outer mouth (3, 5) then into the central mouth (4).

Description

Motor vehicle hot air blower designed as a hand-held device

The invention relates to a motor vehicle hot air blower designed as a hand-held device, which is designed for battery operation and has radiators arranged in the flow path of the 5 blower air and an outlet nozzle as hot air outlet, in which at least one outflow channel is designed with a slot-shaped outlet mouth.

0 Such a hot air blower is from DE-GM

1 962 400 known. It can be connected to the motor vehicle battery via a cable and a plug which fits into the socket of the cigarette lighter of the motor vehicle and can be used for deicing the motor vehicle windows from the inside or from the outside. The outlet nozzle is designed here as a slot die, the mouth slot of which is relatively narrow, so that the heated fan air has the highest possible flow velocity and the heat transfer from the hot air flowing out to the window to be de-iced is as large as possible. In the case of a relatively narrow mouth slot, however, the area swept by the hot air is also relatively small, so that if the panes are more iced up, a considerable amount of time remains until the ice has thawed over the entire pane. In contrast, the invention provides a motor vehicle hot air blower designed as a hand-held device for defrosting motor vehicle windows, in which large window surfaces can be defrosted in a short time without significantly increasing the heating and / or blower output.

According to the invention, a plurality of outflow ducts which are tapering toward their slot-shaped outlet mouth are formed in the outlet nozzle, the slot-shaped outlet mouths of which run at a distance from one another and on the wall of which the radiators are arranged.

The arrangement of a plurality of slot-shaped outlet orifices spaced next to one another at a distance can be relatively narrow for the highest possible exit velocity of the hot air, while the outflowing hot air nevertheless acts on a much larger disk area than the cross-sectional area of the outlet orifices. Between two adjacent slot-shaped outlet openings, namely, a space delimited on both sides by the hot air flows that flow out of the adjacent outlet openings by hot air curtains, in which the air is held between the two hot air curtains, is heated up relatively quickly and under the influence of the neighboring ones slot-shaped outlet orifices are swirled with escaping hot air streams. In addition, part of the hot air streams emerging from the adjacent slot-shaped outlet orifices is deflected towards one another at the disks to be de-iced. All of this leads to a significantly better utilization of the heat transferred by the hot air to the pane to be de-iced for thawing the pane covering ice or snow. In contrast, in the presence of a single slot-shaped outlet opening, a substantial part of the hot air flowing out along the * slot edges flows off to the side without reaching the pane surface to be de-iced, so that a substantial part of the heat transferred to the fan air by the radiators remains unused.

The invention therefore makes great use of the heat content of the hot air to defrost the pane, so that despite a higher defrosting efficiency an increase in the blower and heating capacity is not necessary and a relatively large pane area can be defrosted effectively in a short time.

In the solution according to the invention there are thus at least two slot-shaped outlet openings running along one another at a distance from one another. Their distance from one another can be a multiple of the slot width, in particular a size of up to several cm.

Due to the tapering shape of the outflow channels towards their outlet mouth and the arrangement of the radiators within the tapering outflow channels, there is a good heat transfer from the radiators to the blower air flowing past, so that there is a good heating efficiency.

The slot-shaped outlet orifices preferably extend at equal distances from one another along their length. You can run curved, for example, be designed as concentric ring slots. However, it is preferred that the slot-shaped outlet orifices are rectangular in cross section and run parallel to one another.

OMPI ° ' If there are more than two outflow channels with slot-shaped outlet openings, in a preferred embodiment of the invention such a constructive design of the outflow channels and / or arrangement, distribution and design performance of their radiators can be ensured that those from the outside slot-shaped outlet openings escaping fan air has a higher temperature than that from each central outlet mouth lying between the outer outlet mouth. In this way, the two outer discharge slots may be used in relatively large Ab¬ stood from each other extend, so that the both sides bounded by the outer slit-shaped outlet orifices field is relatively large, while the opening out between the two sides of the field mean exit _^ mouths of the heat influx into the central region of the field for its rapid warming. On the basis of the principle of the invention, however, a lower heat input than in the area of the side edges of the field is sufficient so that the overall heating output of the hot air blower remains low.

In the preferred solution, the different temperature distribution of the hot air over the row of slot-shaped outlet openings becomes easier

This is achieved in that the mouth cross section of the outer outflow channels is smaller than that of each outflow channel lying between them. In the case of inlet cross sections of the outflow ducts for the blower air which are of approximately the same size, this is distributed to the outflow ducts on account of the outlet pressure which is essentially the same across the outlet orifices of the outflow ducts and is subjected to such flow conditions that the two outer outflow ducts are heated to a greater extent air flowing through takes place as in each of the narrowing less than the outer outflow channels

f OMP middle outflow channels. The cross-section of the mouth of the outer outflow channels is advantageously half as large as that of each outflow channel lying between them.

Although two or four or even more outflow channels with a slot-shaped outlet mouth can also be formed in the outlet nozzle, three outflow channels are preferably provided, of which at least the two outer outflow channels extend continuously from the inlet side of the outlet nozzle. ' boys. The middle outlet channel, on the other hand, can also have a cross-section that is constant over its length. In this case, the two outer outlet channels are expediently equipped with radiators on their wall surfaces adjacent to the middle outlet channel, while the middle outlet channel on both of them adjoins the outer outlet channel Wall surfaces is provided with radiators.

The radiators can be designed in a manner known per se, in particular as electrical resistance wires, which preferably run along almost the entire length of the outflow ducts at a distance from their wall surface, so that they are washed all around by the blown air flowing past. As is also known per se, a suitable distribution and design of the heating wires, for example in the form of coils, can produce a turbulent flow in their area in order to achieve the best possible heat transfer to the air to be heated .

Like the known motor vehicle hot air blower mentioned at the outset, the hot air blower according to the invention can also be equipped with a cable with a plug attached to it for the socket of the cigarette lighter of motor vehicles. If applicable

O PI ^• It is also possible to equip the hot air blower with a rechargeable battery, which may contain a charging connection for an external charger.

In a further embodiment of the invention, such a motor vehicle hot air blower is created. which is particularly compact and small, so that it takes up little space and can, for example, be kept within reach in the glove compartment of the vehicle.

According to this embodiment, the housing is tubular with an outlet nozzle formed on the one tube end and the air inlet opening formed on the other tube end, while at the one tube end, preferably the tube end having the outlet nozzle, a rod-shaped hand is fastened to the tubular housing and can be folded down and out of the free end of the handle the cable is led out.

This creates a relatively small and handy device, which is not bulky after folding the handle on the long side of the tubular housing and has a small space requirement, so that it can easily be stored even in a small space.

Nevertheless, the device according to the invention can also be held on the outstretched arm on the handle that is then extended and can be handled in the desired position. Preferably, the joint on which the handle is articulated to the tubular housing is designed in a self-locking manner in such a way that intermediate positions for the handle are also possible without the device itself being able to pivot about the joint under its weight.

Within the tubular housing of the Elektromo¬ can be supported in such a way ^'tor that circumferentially between its Außen¬ and the inside of the tubular housing a

f OMPI There is a passage gap for the blower air for the passage from the impeller located between the electric motor and the air inlet opening to the heating device and the outlet nozzle.

The cable can be firmly attached in the end of the handle. be closed. Preferably, however, a connecting socket is disposed, while ^'has the cable a sleeve for insertion in this Connection designed mating connector in the end of the handle. For this connection socket, a commercially available connection socket is preferably used, which is designed in the manner of the connection socket of the cigarette lighter of the motor vehicle. ^' By forming a plug-in connection for the cable, this can be detached from it for storing the device and stored separately, so that the space requirement is further reduced.

Overall, the invention thus creates a motor vehicle hot air blower for defrosting motor vehicle windows, which has a high degree of efficiency with a relatively low output and also effectively defrosts heavily icy windows in a short time.

The invention is explained on the basis of exemplary embodiments which can be seen from the drawing. The drawing shows:

1 is a schematic perspective representation of a first embodiment of a motor vehicle hot air blower,

2 shows the section corresponding to the arrows in FIG. 1 through the outlet nozzle of the hot air blower and

OMPI Fig. 3 is a partially sectioned side view of a second embodiment.

As can be seen from FIG. 1, the hot air blower 1 contains a conventional radial fan, to the tangential outlet opening of which a box-shaped outlet nozzle 2 is connected. The hot air blower is designed for operation with a motor vehicle battery and can be connected to the socket of the cigarette lighter of the motor vehicle via the cable 10 and the plug 11. A bow-shaped handle 14 is attached to the housing of the radial air blower. The blower air is drawn in through the suction opening 13 covered with a grille. The cable can be wound onto hooks 12 attached to the side of the housing of the radial fan.

As can further be seen from FIG. 1, the outlet nozzle 2 has a plurality of slit-shaped outlet openings 3, 4, 5 at its mouth, which in the embodiment shown run parallel to the narrow sides of the outlet nozzle 2 at a distance from one another. However, it is also possible for the outlet openings 3, 4, 5 to be parallel to the

Let the broad sides of the outlet nozzle 2 run.

2 shows a section through the outlet nozzle perpendicular to the slot-shaped outlet openings 3, 4, 5. Over the entire length of the outlet nozzle 2, three outflow channels 6, 7, 8 are formed in it, which are located on the inlet side 15 of the outlet nozzle 2 have the same inlet cross-section and taper from there to the outlet openings 3, 4, 5 in a wedge shape. The Aus¬ flow channels 6, 7, 8 are in the interior of the outlet ^■ 2 of heat-resistant and electrically insulating plates 16, for example, mica or ceramic plates, be¬ borders at which substantially the entire length of the outflow channels 6, 7, 8 towards Radiator 9 in the form of heating helices wound from electrical resistance wire are clamped, which are electrically connected (not shown) to two line wires of the connecting cable in the manner customary for heating wires of 'hot fans'.

As can be seen from FIG. 2, the two outer outflow ducts 6, 8 are equipped with radiators only on their boundary wall adjacent to the middle outflow duct 7, while the middle outflow duct 7 is equipped with radiators 9 on both boundary walls adjacent to the outer outflow ducts 6, 8 is.

As can further be seen from FIG. 2, the two slit-shaped outlet orifices 3, 5 of the two outer outflow channels 6 and 8 have a smaller slot width than the slit-shaped outlet orifice 4 of the central outflow channel 7. Due to the resulting different pressures and flow velocities in the outer outflow ducts 6, 8 on the one hand and the middle outflow duct 7 on the other hand results in a higher temperature for the blower air emerging from the outer outlet openings 3, 5 than for the blower air emerging from the middle outlet mouth 4. As a result, an approximately fan-shaped flow field with curtain-like hot air flows on the two opposite sides of the flow field is obtained at the outlet of the outlet nozzle 2, while the air flow emerging from the central outlet mouth 4 has a lower temperature. However, since part of the two outer hot air streams on their mutually opposite inner sides likewise flows into the space between these outer air streams and another part of the outer hot air streams on the pane to be de-iced is deflected inward into the space between them , the middle field of the window to be de-iced receives an additional heat between the two outer air flows in addition to the heat supplied by the middle air flow.

O PI additional amount of heat from the two outer air streams so that as a result the entire field delimited by the two outer air streams is heated approximately uniformly. In this way, the heat transported by the two outer air streams is better utilized because the amount of heat dissipated from the two inner sides of these outer air streams does not escape unused, but is also used to thaw the iron on the pane to be de-iced.

Although the outlet nozzle 2 is shown in FIG. 2 with an overall rectangular longitudinal section, it can, as can be seen from FIG. 1, also have an overall trapezoidal longitudinal section, the large trapezoidal side of which forms the outlet side of the outlet nozzle 2.

The hot air blower shown in FIG. 3 has a tubular housing 20, at the front end of which an outlet nozzle 2 is formed with a rectangular outline, in which three outflow channels 6, 7 and 8 are formed at a mutual distance from one another. In the embodiment shown, ge taper the two äu¬ ßren outflow channels 6 and 8 to their respective Aus¬ occurs muzzle ^'3, 5 out while the central outflow channel 7 has a round constant over its length Durch¬ strömquerschnitt and its outlet opening 4 is larger in cross-section than each of the outlet orifices 3, 5 of the outer outflow ducts 6, 8. In the outflow ducts, an electrical heating device, not shown in the drawing, is arranged in the path of the incoming blower air.

Approximately in the middle of the tubular housing 20, an electric motor 22 is supported in the housing 20 by means of projecting ribs 25 such that a ring channel 26 for the air supplied to the outlet nozzle 2 is present around the motor 22. The shaft 30 of the motor 22 is opposed by this on that of the outlet nozzle 2 1 set down side and carries an impeller, which consists of a guide body 23 which increases towards the motor 22 to its diameter, with vanes 24 projecting radially thereon. At the rear pipe end ^ of the housing 20, a cover plate 27 is inserted, which has an air inlet opening 13 in the center of a much smaller diameter than the outer diameter of the impeller, so that the air flows centrally into the impeller and according to the arrows shown in the ring channel 26 is promoted.

At the front end of the tubular housing 20, a support bracket 31 is integrally formed thereon, to which a handle 21 is articulated via a swivel joint 32,

15 which can be folded down from the position drawn with solid lines, in which it protrudes vertically from the housing 20, into the position shown in broken lines, in which it lies against the housing 20 along the latter. The handle 21 has

20 hollow profile. In its interior there is a switch (not shown), the actuating element 33 of which protrudes from the handle 21 at the front and via which the electric motor 22 and the heating device are connected to the contacts of a connecting socket 28,

25 which is inserted from the open end into the handle 21 and fixed to it.

The connection socket 28 is designed in the manner of the socket of the cigarette lighter of a motor vehicle.

30 The associated cable 10 has at its one end a correspondingly designed mating connector 29 and at its other end a second connector 11, which fits into the socket of the cigarette lighter. The length of the cable 10 is relatively long,

- "so that the device when connected to the interior of the motor vehicle cable 10 outside the vehicle

OMPI IPO - whose disks or in whose engine compartment can be handled.

OM

Claims

Expectations

1. Motor vehicle hot air blower designed as a hand-held device, which is designed for battery operation and has radiators arranged in the flow path of the blower air and an outlet nozzle as hot air outlet, in which at least one outflow channel is formed with a slot-shaped outlet mouth, characterized in that that several outlet channels (6, 7, 8) tapering towards their slot-shaped outlet mouth (3, 4, 5) are formed in the outlet nozzle (2), the slot-shaped outlet openings (3, 4, 5) of which in the outlet stood apart from each other and in which the radiators (9) are arranged.

2. Hot air blower according to claim 1, characterized in that the slot-shaped outlet mouths (3, 4, 5) are rectangular and run parallel to each other.

Hot air blower according to claim 1 or 2, characterized in that the outflow channels (6, 7, 8) and / or their radiators (9) for a higher outlet temperature of the blower air at the outer slot-shaped outlet openings (3, 5) than the outlet temperature of the Blower air at each central outlet mouth (4) are designed.

JJlE TT-

OMPI 4. Hot air blower according to claim 3, characterized gekenn¬ characterized in that the .Mouth cross section of the outer outflow channels (6, 8) is smaller than that of each outflow channel (7) lying between them.

5. Hot air blower according to .Anspruch 4, characterized gekenn¬ characterized in that the mouth cross-section of the outer outflow channels (6, 8) is half as large as that of each outflow channel (7) between them.

6. Hot air blower according to one of claims 1 to 5, characterized in that three outflow channels (6, 7, 8) are provided, which, from the inlet side of the outlet nozzle (2) taper off continuously, and that the two outer outflow channels (6, 8) on their wall surface adjacent to the central outflow channel (7) and the middle outflow channel (7) on both wall surfaces adjacent to the outer outflow channels (6, 8) are equipped with radiators (9).

7. Hot air blower according to one of claims 1 to 6, in which an electric motor with an impeller seated on its shaft and an electric heating device arranged in the flow path of the blower air are accommodated in a housing and on the housing an outlet nozzle as a hot air outlet and an air inlet opening as an inlet are designed for the blown air, and in which the electric motor and the heating device are connected via a switch and a cable to a connector at the end of the connector for the socket of the cigarette lighter of a motor vehicle, characterized in that the housing (20) tubular with an outlet nozzle (2) formed on one end of the tube and on the other Pipe end of trained air inlet opening (13) is designed and has at one end a hinged handle (21), from the end of which the cable (10) is led out.

8. hot air blower according to claim 7, characterized marked ^• characterized in that in the end of the handle (21) has a socket (28) and having the cable (10), one for the insertion into this designed mating connector (29).