Refrigeration – Automatic control – Refrigeration producer
Patent
1986-03-27
1989-01-31
Wayner, William E.
Refrigeration
Automatic control
Refrigeration producer
623234, F25B
Patent
active
048007307
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The invention relates to an arrangement of the type set forth in the preamble of claim 1.
BACKGROUND OF THE INVENTION
In refrigerating systems as used in motor vehicles, for example in refrigerated vehicles or in the air-conditioning systems of omnibuses or automobiles, the compressor is generally driven by the internal combustion engine provided for driving the motor vehicle. With these internal combustion engines in travelling operation very different speeds occur which can lie in a range of for example 450 r.p.m. to 10000 r.p.m. To ensure that the refrigerating power of the refrigerating system remains substantially constant, however, the speed of the compressor should vary as little as possible. A usual nominal speed of the compressor is for example 2400 r.p.m. The changes in the speeds are particularly great in the case of internal combustion engines of omnibuses travelling from one bus stop to the next so that in them the speed varies continuously over the entire range. In this case in the prior art it is hardly possible to design an air-conditioning system which is optimally constructed for the air-conditioning of the bus. In the case of refrigerated vehicles in the prior art even a separate drive motor running with a constant speed is used for the drive of the compressor because a constant compressor speed cannot be achieved via the internal combustion engine provided for the drive of the refrigerated vehicle. However, the use of a separate drive motor for the compressor is expensive and uneconomical because the vehicle must carry an additional motor whose additional weight decreases the efficiency of the vehicle. Usually, such a separate drive motor for the compressor is also an internal combustion engine. Alternatively, however, electrical generators have already been used which are coupled to the drive internal combustion engine and supply an electric motor with current via an appropriate control in such a manner that said electric motor drives the compressor with a constant speed. This known arrangement for influencing the speed of a compressor of a refrigerating system is however even more expensive than that previously described because it involves more outlay and because the electrical generator must be designed for the entire range of the speed of the internal combustion engine, i.e. must practically be considerably overdimensioned.
To avoid these disadvantages of the arrangements described for influencing the speed of rotation of a compressor in a further known arrangement a magnetic slip coupling is simply used which couples one of the V-belt pulleys of the V-belt drive of the compressor to the associated shaft of the internal combustion engine provided for the drive of the vehicle or of the compressor. The V-belt drive has a fixed transmission ratio, the speed of the internal combustion engine is measured and from a certain nominal speed of the compressor onwards the latter is uncoupled by the magnetic coupling. The magnetic coupling then operates from the nominal speed onwards with slip and as a result high thermal stresses occur in the magnetic coupling and frequently lead to failure of such magnetic couplings. A further disadvantage is that the compressor is driven beneath the nominal speed with the variable speed of the internal combustion engine, i.e. cannot provide a constant delivery. Operation of the compressor with a speed below its nominal speed involves a further disadvantage because with decreasing compressor speed less refrigerant is taken from the evaporator by the compressor and in the extreme case this can lead to the evaporator being flooded, i.e. filling with liquid refrigerant. Since liquid is not compressible to avoid destruction of the compressor the latter must be made substantially larger than really necessary. This involves further additional weight, which is fundamentally unfavourable in motor vehicles.
Moreover, these known arrangements influence the speed of the compressor of the refrigerating system only in dependence upon the speed
REFERENCES:
patent: 942499 (1909-12-01), Heinrich
patent: 2130995 (1938-09-01), Henney
patent: 2151987 (1939-03-01), Perrine
patent: 2227257 (1940-12-01), Henney et al.
patent: 2320432 (1943-06-01), Henney
patent: 2626506 (1953-01-01), Dickieson, Jr.
patent: 2720087 (1955-10-01), Groene
patent: 3220211 (1965-11-01), Nordguest
patent: 3365906 (1968-01-01), Zadig
Lehrbuch der Kaltetechnik, pp. 268 ff.
Konstruieren von Getrieben, pp. 242 ff.
Hipfl Wolfgang E.
Lamm Hermut
Poschl Gunter
Eilberg William H.
Suetrak Transportkaelte GmbH
Wayner William E.
LandOfFree
Arrangement for influencing the speed of a compressor of a refri does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Arrangement for influencing the speed of a compressor of a refri, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Arrangement for influencing the speed of a compressor of a refri will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-171662