Note: Descriptions are shown in the official language in which they were submitted.
-
CA 022144~6 1997-09-18
AUXILIARY HEAT SOURCE APPARATUS FOR VEHICLE
AND
HEATING APPARATUS EMPLOYING THE SAME
BACKGROUND OF THE INVENTION
1. Field of the Invention:
The present invention relates to an auxiliary heat
source apparatus for a vehicle, which improves a heating
capacity for a passenger compartment of the vehicle by using
heat generated by viscous fluid in a heat-generating chamber
when a shearing force is applied thereto.
2. Description of Related Art:
Conventionally, as a heating apparatus for a vehicle,
there has been generally known a hot water type heating
apparatus for heating a passenger compartment, in which cooling
water for cooling a water-cooled engine is supplied to a heater
core disposed in a duct, and air heated while passing through
the heater core is blown into the passenger compartment by a
blower to heat the passenger compartment.
Further, in a case of the vehicle where the heat amount
generated by the engine is small, such as a vehicle having a
diesel engine or a lean burn engine, because the heat amount
generated by the engine is too small to heat the cooling water
sufficiently, a temperature of the cooling water in the cooling
water circuit cannot be maintained at a predetermined
temperature (e.g., 80~C), there occurs a problem in that a
heating capacity for the passenger compartment is insufficient.
--1--
CA 022144~6 1997-09-18
To overcome such a problem, as disclosed in JP-A-2-
246823, there has been conventionally proposed a heating
apparatus for a vehicle, in which a heat-generating unit using
a shearing force is disposed in a cooling water circuit for
supplying cooling water from an engine to a heater core, and
when a temperature of the cooling water in the cooling water
circuit is lower than a predetermined temperature, the heat-
generating unit is operated to improve the heating capacity.
The heat-generating unit transmits a rotational driving
force of the engine to a shaft through a belt transmitting
mechanism and an electromagnetic clutch, the heat-generating
chamber is formed in a housing, and a cooling water passage is
formed at an outer periphery of the heat-generating chamber.
Further, a rotor which rotates integrally with the shaft is
disposed in the heat-generating chamber, and a shearing force
generated by a rotation of the rotor is applied to viscous
fluid such as silicon oil sealed in the heat-generating chamber
to generate heat. The cooling water is heated by the generated
heat.
However, in the heating apparatus for a vehicle,
equipped with the conventional heat-generating unit using the
shearing force, when the heat-generating unit is started, i.e.,
that is, when a rotational driving force of the engine starts
to be transmitted to the rotor, the rotor is started in the
viscous fluid, and a large torque is applied to the rotor, the
electromagnetic clutch, and the belt mechanism. As a result,
there occurs a problem that a slipping of the electromagnetic
--2--
CA 022144~6 1997-09-18
clutch may be caused, or abnormal noise (chattering noise) may
be generated by a slipping of a belt of the belt mechanism.
Especially, when the heat-generating unit using the
shearing force is started after being left for a long time in
winter season where the outside air temperature is low, because
the viscosity of the viscous fluid having a low temperature is
extremely high, a shock applied to the rotor is extremely high,
and a stress applied to each parts of the heat-generating unit
becomes extremely high. Therefore, there occurs a problem that
durability of each portion of the heat-generating unit may
deteriorate. When the electromagnetic clutch is turned on or
off to control the heating capacity for the passenger
compartment, the problem similar to that when the heat-
generating unit is started occurs.
SUMMARY OF THE INVENTION
In view of the above-described problems, it is
accordingly an object of the present invention to provide an
auxiliary heat source apparatus for a vehicle, capable of
improving the durability of each portion of the heat-generating
unit by reducing the stress applied to each portion of the
heat-generating unit when the rotor of the heat-generating unit
is started.
According to the present invention, in an auxiliary
heat source apparatus for a vehicle having a driving source, a
heat-generating unit using a shearing force, for heating a
thermal medium by heat generated by a viscous fluid in a heat-
--3--
CA 022144~6 1997-09-18
generating chamber thereof when a shearing force by a
rotational driving force of a rotor is applied thereto, is
provided with liquid level dropping means for temporarily
dropping the liquid level of the viscous fluid in the heat-
generating chamber when a rotational speed of the rotor is less
than a predetermined rotational speed.
In this way, by means of the liquid level dropping
means disposed in the heat-generating chamber, when the
rotational speed of the rotor is less than a predetermined
rotational speed, the liquid level of the viscous fluid in the
heat-generating chamber temporarily drops. Therefore, torque
on starting the rotor can be reduced, and shock to the rotor
is relieved. Accordingly, stress applied to each portion of
the heat-generating unit can be reduced, and the noise
generated can be suppressed.
Further, even if a clutch dr~ven by and connected to
the driving source, for intermittently transmitting the
rotational driving force from the driving source to the rotor
is employed, or a driving force transmitting means disposed
between the driving source and the clutch is further employed,
the stress applied to the clutch or the driving force
transmitting means can be reduced on starting of the rotor,
and the noise generated can be suppressed.
Further, as liquid level dropping means, a storage
portion may be formed at a lower portion of the heat-generating
chamber in fluid communication therewith, into which the
viScous fluid in the heat-generating chamber flows by gravity
--4--
CA 022144~6 1997-09-18
under its own weight.
Still further, the liquid level dropping means may drop
the liquid level of the viscous fluid in the heat-generating
chamber to be lower than a rotation center of the rotor. In
this way, the torque at the start of the rotor can be greatly
reduced.
Further, the liquid level dropping means may drop the
liquid level of the viscous fluid in the heat-generating
chamber to such an extent that only an amount of the viscous
fluid in contact with an outer peripheral surface of the rotor
remains in the heat-generating chamber. In this way, the
torque at the start of the rotor can be further greatly
reduced.
The above-described auxiliary heat source apparatus can
be preferably employed in a heating apparatus having a heating
heat exchanger for heating a passenger compartment of the
vehicle by heat-exchanging between cooling water having cooled
a water-cooled engine and air to be blown into the passenger
compartment, to heat the cooling water.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Additional objects and advantages of the present
invention will be more readily apparent from the following
detailed description of preferred embodiments thereof when
taken together with the accompanying drawings in which:
FIG. 1 is a schematic view showing an entire structure
of an air conditioning apparatus for a vehicle, according to a
--5--
CA 022144~6 1997-09-18
first embodiment of the present invention;
FIG. 2 is a schematic view showing an engine and a belt
transmission mechanism in the first embodiment;
FIG. 3 is a transverse cross sectional view showing a
5viscous clutch and a viscous heater in the first embodiment;
FIG. 4 is a longitudinal cross sectional view showing
the viscous heater in the first embodiment;
FIGS. 5A and 5B are explanatory views show a variation
of a liquid level of a high-viscosity oil according to
10operation states of a rotor; and
FIG. 6 is a longitudinal cross sectional view showing
the viscous heater according to a second embodiment of the
present invention.
15DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1 to 5 show a first embodiment of the present
invention. FIG. 1 shows an entire structure of an air
conditioning apparatus for a vehicle, and FIG. 2 shows an
engine and a belt transmitting mechanism.
20An air conditioning apparatus 1 for a vehicle is
equipped with a water-cooled diesel engine E (hereinafter
referred to as "engine") disposed in an engine compartment of
a vehicle, an air conditioning unit (hereinafter referred to as
~A/C unit") 3 for air-conditioning a passenger compartment, a
25belt transmitting mechanism driven by and connected to the
engine E, an electromagnetic clutch 4 driven by and connected
to the belt transmitting mechanism, a viscous heater 5 using
--6--
CA 022144~6 1997-09-18
heat generated when a rotational driving force of the engine E
is transmitted thereto through the electromagnetic clutch 4 as
an auxiliary heat source apparatus, an engine control unit (not
shown) for controlling the engine E, and an air-conditioning
control unit (not shown) for controlling the A/C unit 3.
The engine E which is a driving source for driving the
viscous heater 5 is disposed in a cooling water circuit 2
through which cooling water circulates and has a water jacket
therein. In the cooling water circuit 2, there is disposed a
water pump 11 for pumping the cooling water in the cooling
water circuit 2. Further, to an output shaft (crankshaft) 12
of the engine E, there is attached a crank pulley 13 driven by
and connected to the belt transmitting mechanism.
The A/C unit 3 is constructed by a duct 14, a blower
15, an evaporator 16 of a refrigeration cycle, a heater core 17
disposed in the cooling water circuit 2, and the like. At an
upwind side of the duct 14, there is rotatably provided an
inside air/outside air switching door 18 for selectively
opening and closing an outside air inlet 18a and an inside air
inlet 18b to switch an air inlet mode.
At an downwind side of the duct 14, there is rotatably
provided a mode switching door 19 for selectively opening and
closing a defroster air outlet l9a, a face air outlet l9b and
a foot air outlet l9c to switch an air outlet mode.
The blower 15 is rotated by a blower motor 20 to
generate an air flow toward the passenger compartment in the
duct 14.
CA 022144~6 1997-09-18
The evaporator 16 is a refrigerant evaporator for
cooling the air flowing in the duct 14 and constructs the
refrigeration cycle with a compressor, a condenser (refrigerant
condenser), a receiver (gas-liquid separator), and an expansion
valve (decompressing device). The compressor is a refrigerant
compressor for compressing and discharging the refrigerant when
a rotational driving force is applied thereto. A V-pulley 22
driven by and connected to a driving shaft 21 of the compressor
is driven by and connected to the crank pulley 13 of the engine
E through a V-belt (described later) of the belt transmitting
mechanism.
The heater core 17 is disposed within the duct 14 at a
downstream side (downwind side) of the evaporator 16 with
reference to the air flow direction and is connected to the
cooling water circuit 2 at a downstream side of the viscous
heater 5 with reference to the flow direction of the cooling
water. The heater core 17 is a heating heat exchanger for
heating air by heat-exchanging the air having passed through
the evaporator 16 and the cooling water. At an upwind side of
the front heater core 15, there is rotatably provided an air-
mixing door 23. The air-mixing door 23 adjusts a ratio between
an amount of air (warm air) passing through the front heater
core 17 and an amount of air (cool air) bypassing the heater
core 17 so that a temperature of air blown out into the
passenger compartment can be adjusted.
The belt transmitting mechanism is composed of a multi-
stage type V-belt for drivingly connecting the crank pulley 13
--8--
CA 022144~6 1997-09-18
of the engine E, the V-pulley 10 of the electromagnetic clutch
4, and the V-pulley of the compressor. The V-belt 6 is for
transmitting a rotational driving force of the engine E to
the viscous heater 5 and the compressor. The V-belt 6 of the
belt transmitting mechanism may be also hung on a V-pulley of
an auxiliary equipment for an engine (such as a hydraulic pump
for pumping lubricating oil to the engine E) a V-pulley of the
water pump 11, or the like.
The electromagnetic clutch 4 is for intermitting a
rotational driving force transmitted from the engine E to a
shaft 7 and a rotor 9 of the viscous heater 5, as shown in FIG.
3. The electromagnetic clutch 4 is constructed by an
electromagnetic coil 31 for generating a magnetomotive force
when an electric current is supplied thereto, a rotor 32
rotated by the engine E, an armature 33 attracted toward the
rotor 32 by the magnetomotive force, an inner hub 35 connected
to the armature 33 with a plate spring 34 and supplying a
rotational driving force to the shaft 7 of the viscous heater
5, and the like.
The electromagnetic coil 31 is structured by winding a
conductive lead wire covered with an insulating material. The
electromagnetic coil 31 is disposed in a stator 36 and is
fixedly molded in the stator 36 with an epoxy resin. The
stator 36 is fixed on a front surface of a housing 8 of the
viscous heater 5.
A V-pulley 10 for hanging the V-belt 6 on a periphery
thereof is joined to the rotor 32 by joining means such as
_g_
CA 022144~6 1997-09-18
welding. The rotor 32 is a rotating body (input portion of the
electromagnetic clutch 4) which always rotates by a rotational
driving force of the engine E, transmitted thereto through the
V-belt 6. The V-belt 6 is hung on the V-pulley 10, and the V-
pulley 10 always rotates by a rotational driving force of the
engine E, transmitted thereto through the V-belt 6. The rotor
33 is a first friction member formed of magnetic material to
have a U-shaped cross section and is rotatably supported on an
outer periphery of the housing 8 of the viscous heater 5 with
a bearing 48 disposed in an inner periphery thereof.
The armature 33 is a second friction member formed of
magnetic material and having a friction surface formed in a
ring-shaped plate, which is opposed to a friction surface of
the rotor 32, formed in a ring-shaped plate, by an air gap
(e.g., a clearance of 0.5 mm) therebetween. When the armature
43 is attracted to the friction surface of the rotor 32 by the
electromotive force of the electromagnetic coil 31, the
rotational driving force of the engine E is transmitted from
the rotor 32 to the armature 33.
The plate spring 34 is fixed to the armature 33 at an
outer peripheral side by fixing means such as a rivet and is
fixed to the inner hub 35 at an inner peripheral side by fixing
means such as a rivet. The plate spring 34 is an elastic
member for displacing the armature 33 in a direction (the left
direction in the drawing) as to be separated (released) from
the friction surface of the rotor 32 when the supply of the
electric current to the electromagnetic coil 31 is stopped, to
--10--
CA 022144~6 1997-09-18
return the armature 33 to an initial position thereof.
The inner hub 35 is an output portion of the
electromagnetic clutch 4 such that the input side thereof is
connected to and driven by the armature 33 through the plate
spring 34 and the output side is connected to and driven by the
shaft 7 of the viscous heater 5 with a spline fitting
connection.
The viscous heater 5 is a heat-generating unit using a
shearing force, and is constructed by, as shown by FIGS. 3 to
5, the shaft 7 rotated by the engine E through the V-belt 6 and
the electromagnetic clutch 4, the housing 8 for rotatably
supporting the shaft 7, a separator 50 for dividing an inner
space of the housing 10 into an oil chamber 41 and a cooling
water passage 51, a rotor 9 rotatably disposed in the housing
8, and the like.
The shaft 7 is a rotary shaft (input shaft) which is
fixedly fastened to the inner hub 35 of the electromagnetic
clutch 4 by fastening means 42 such as a bolt and rotates
integrally with the armature 33. The shaft 7 is rotatably
disposed in an inner periphery of the housing 8 with a bearing
43 such as a ball bearing and a sealing member 44. The sealing
member 44 employs an oil-seal for preventing a leakage of the
high-viscosity oil.
The housing 8 is made of a metallic member such as
aluminum alloy. A cover 45 formed in a ring-shaped plate is
fixedly fastened to a rear end of the housing 8 by fastening
means 46 such as a bolt. On a surface where the housing 8 and
--11--
CA 022144~6 1997-09-18
the cover 45 are joined, there are disposed the separator 50
and a sealing member 47. The sealing member 47 employs an oil-
seal for preventing a leakage of the high-viscosity oil. In an
oil chamber 41 formed between a rear end surface of the housing
8 and a front end surface of the separator 50, there are
provided a heat-generating chamber (shearing chamber) 48 in
communication with an oil storage chamber (oil storage tank-) 49
both for retaining sealing high-viscosity oil (viscous fluid
such as silicon oil) which generates heat when a shearing force
is applied thereto. When the rotation of the rotor 9 is
stopped, both of the heat-generating chamber 48 and the oil
storage chamber 49 accumulate approximately 30 g (approximately
30 cc) of the high-viscosity oil.
The oil storage chamber 49 is, as shown in FIGS. 3 and
4, formed below the heat-generating chamber 48 in communication
therewith. The oil storage chamber 49 is formed to expand in
such a manner that its size thereof in the axial direction
(front-rear direction) is larger than that of the heat-
generating chamber 48 as is the size of the oil storage
chamber 49 in the rotational direction of the rotor 9. The oil
storage chamber 49 may be formed to expand, relative to the
heat-generating chamber 48, in the downward radial direction of
the rotor 9, to the extent that the amount of the high-
viscosity oil in the heat-generating chamber 48 can be reduced
when the rotation of the rotor 9 is stopped.
The oil storage chamber 49 is for dropping the liquid
level of the high-viscosity oil in the heat-generating chamber
-12-
CA 022144~6 1997-09-18
48 to be lower than a rotation center of the shaft 7 and the
rotor 9, because the high-viscosity oil in the heat-generating
chamber flows into the oil storage chamber 49 under its own
weight when the rotation of the rotor 9 is stopped. A volume
of the oil storage chamber 49 is set so that the high-viscosity
oil contacts an outer peripheral portion of the rotor 9 (5 mm
of overlap with the margin of the rotor 9, or from 5 percent to
20 percent both inclusive of the outer surface of the rotor 9)
when the rotation of the rotor 9 is stopped, i.e., all of the
high-viscosity oil is in the oil storage chamber 49. The oil
storage chamber 49 may be formed to reduce the liquid level of
the viscous fluid in the heat-generating chamber 48 in such a
manner that only a certain amount of the viscous fluid remains
in contact with the outer surface of the rotor 9 in the heat-
generating chamber 48 when the rotation of the rotor 9 isstopped. Further, the heat-generating chamber 48 may be of a
labyrinth structure formed between the separator 50 and the
rotor 9 and having a space formed with a curvature of 1 or
more.
The separator 50 is a partition member which is made of
a metallic member such as aluminum alloy, which is superior in
heat conductivity. An outer peripheral portion of the
separator 50 is sandwiched between a cylindrical portion of the
housing 8 and a cylindrical portion of the cover 45. Between
a rear end surface and the cover 45, there is formed the
cooling water passage 51, which are liquid-tightly partitioned
from the outside and in which the cooling water having cooled
CA 022144~6 1997-09-18
the engine E circulates. Further, on the rear end surface of
the separator 50 at a lower side, there are integrally formed
a plurality of fin portions (not shown) having a substantially
arcuate shape, for transmitting heat of the high-viscosity oil
to the cooling water efficiently. Instead of the fin portions,
the rear end surface of the separator 50 may be formed in a
convex and concave shape, or a heat transmission facilitating
member such as a corrugated fin and a fine pin fin may be
provided on a rear end surface of the separator 50.
The cooling water passage 51 is partitioned into an
upstream side water passage 51a and a downstream side water
passage 51b by a partition wall (not shown) formed integrally
with the rear end surface of the separator 52. To an upper end
portion of an outer wall portion of the cover 45, there are
connected an inlet-side cooling water pipe (not shown) for
introducing the cooling water into the cooling water passage 51
and an outlet-side cooling water pipe 52 through which the
cooling water from the inlet-side cooling water pipe flows out.
The rotor 9 is rotatably disposed in the heat-
generating chamber 48 and is fixed to an outer periphery of the
rear end portion of the shaft 7. On an outer peripheral
surface or both side wall surfaces of the rotor 9, there are
formed a plurality of groove portions (not shown). setween the
adjacent groove portions, there is formed a protrusion portion
(tooth portion). When a rotational driving force of the engine
E is supplied to the shaft 7, the rotor 9 rotates integrally
with the shaft 7 to generate a shearing force to the high-
-14-
CA 022144~6 1997-09-18
viscosity oil sealed in the heat-generating chamber 48.
Next, an operation of the air-conditioning apparatus 1
according to the embodiment will be briefly described with
reference to FIGS. 1 to 5.
When the engine E starts, the crankshaft 11 rotates,
and the rotational driving force of the engine E is transmitted
to the rotor 32 of the electromagnetic clutch 4 through the
crank pulley 13, the V-belt 6, and the V-pulley 10. When the
electromagnetic clutch 4 (the electromagnetic coil 31) is not
energized, the armature 33 is not attracted to the friction
surface of the rotor 32, and the rotational driving force of
the engine E is not transmitted to the inner hub 35 and the
shaft 7, with the result that the rotor 42 races simply.
In this way, since the shaft 8 and the rotor 53 do not
rotate, a shearing force is not applied to a part of the high-
viscosity oil in the heat-generating chamber 48. As shown in
FIG. 5A, most of the high-viscosity oil is stored in the oil
storage chamber 49, and the high-viscosity oil does not
generate heat. Therefore, even when the cooling water having
cooled the engine E passes through the cooling water passage 51
of the viscous heater 5, the cooling water is supplied to the
heater core 17 without being heated. Accordingly, a heating
operation for the passenger compartment is started with a small
heating capacity.
Here, when a temperature of the cooling water in the
cooling water circuit 2 is lower than a set cooling water
temperature (set value), the electromagnetic clutch 4 (the
-15-
CA 022144~6 1997-09-18
.
electromagnetic coil 31) is energized. Therefore, the armature
33 is attracted to the friction surface of the rotor 32 with
magnetomotive force of the electromagnetic coil 31 to transmit
the rotational driving force of the engine E to the inner hub
35 and the shaft 7.
In this way, the shaft 7 and the rotor 9 rotate, the
high-viscosity oil in the oil storage chamber 49 is drawn into
the outer peripheral portion of the rotor 9, and is gradually
sucked into contact with the front surface of the rotor 9 so
that the high-viscosity oil fills entirely the heat-generating
chamber 48 as shown in FIG. 5B (Weissenberg ef~ect).
Accordingly, the shearing force is applied to the high-
viscosity oil in the heat-generating chamber 48, and the high-
viscosity oil generates heat. Therefore, when the cooling
water passes through the cooling water passage 51 of the
viscous heater 5, the cooling water is heated by absorbing the
heat generated by the high-viscosity oil. The cooling water
heated by the viscous heater 5 is supplied to the heater core
7, and a heating operation is performed with a large heating
capacity.
The above-described operation is repeated by turning on
or off the electromagnetic coil 31 based on a relationship
between the temperature of the cooling water in the cooling
water circuit 2 and the set cooling water temperature.
As described above, in the viscous heater 5 of this
embodiment, the oil storage chamber 49 is formed below the
heat-generating chamber 48 (in the downward direction). When
-16-
CA 022144~6 1997-09-18
the electromagnetic clutch 4 (the electromagnetic coil 31) is
not energized, i.e., when the rotation of the rotor 9 is
stopped, as shown in FIG. 3 and 5A, the high-viscosity oil in
the heat-generating chamber 48 moves into the oil storage
chamber 49 under its own weight, and the liquid level of the
high-viscosity oil in the heat-generating chamber 48 lowers to
such an extent that the high-viscosity oil contacts only the
outer peripheral portion of the rotor 9.
Accordingly, the torque when the electromagnetic clutch
4 (the electromagnetic coil 31) is energized, i.e., when the
rotor 9 is started, is greatly reduced, and the shock on
starting the rotor 9 is relieved. In this way, the stress
applied to each portion of the viscous heater 5, especially,
the connecting portion between the shaft 7 and the rotor 9,
the connecting portion between the viscous heater 5 and the
shaft 7, the viscous heater 5 and the V-belt 6 can be reduced,
so that the durability of each portion of the viscous heater 5,
and the V-belt can be improved.
Further, because the shock on starting the rotor 9
of the viscous heater 5 is relieved, the slipping between the
V-belt 6 as well as the rotor 32 of the electromagnetic clutch
4 and the armature 33 can be suppressed, and noise such as
belt chattering noise can be suppressed. Accordingly, it is
advantageous to provide the oil storage chamber 49 below the
heat-generating chamber 48 as in this embodiment especially
when the viscous heater 5 is re-started after the vehicle has
been left for a long time in winter season.
-17-
CA 022144~6 1997-09-18
-
Further, by using the heat generated by the viscous
heater 5 as the auxiliary heat source for the heating operation
to assist the engine E as the main heat source for the heating
operation, it is possible to heat the cooling water supplied to
the heater core 17 sufficiently. Therefore, even in a vehicle
where the heat generated by the engine is too small to heat
the cooling water sufficiently with the exhaust heat of the
engine E (e.g., a vehicle having a diesel engine or a lean
burn engine), the temperature of the cooling water in the
cooling water circuit can be maintained approximately at a
predetermined temperature (e.g., 80 C), so that insufficiency
of heating capacity for the passenger compartment can be
prevented.
A second embodiment of the present invention will be
described with reference to FIG. 6.
In this embodiment, to obtain the effects similar to
those in the first embodiment, even in a case where the viscous
heater 5 is mounted on the vehicle which is inclined, the
oil storage chamber 48 is formed in an arcuate shape (e.g., ~
= 30 to 45 ) by extending the size of the oil storage chamber
48 in both the forward and backward direction in respect to
the rotational direction of the rotor 9. Alternatively, the
- extending direction of the oil storage chamber 48 relative to
the rotational direction of the rotor 9 may be either in the
forward or the backward direction, or the tangential line
relative to the rotational direction of the rotor 9 may be
either in the forward direction or the backward direction.
-18-
CA 022144~6 1997-09-18
In each of the above described embodiments, the V-belt
~ and the electromagnetic clutch 4 are connected to and driven
by the crankshaft 12 of the engine E to drive the rotor 9 of
the viscous heater 5; however, the electromagnetic clutch 4 may
be connected directly to the crankshaft 12 of the engine E to
drive the rotor 9 of the viscous heater 5. Further, between
the rotor 9 and the crankshaft 12 of the engine E, there may be
connected a driving force transmitting apparatus (driving force
transmitting means) such as a gear transmission having at least
a one stage gear or a V-belt type non-stage transmission.
Further, other clutch means such as a hydraulic type multiple
disc clutch may be employed.
In each of the above-described embodiments, the water-
cooled engine E is employed as the driving source; however, an
electric motor or hydraulic motor may be employed as the
driving source. Further, the rotor 9 of the viscous heater 5
may be driven by using a water-cooled engine, an air-cooled
engine, or an other internal combustion engine not used as
heat source for heating operation.
In each of the above-described embodiments, the present
invention is applied to an air conditioning apparatus for a
vehicle, capable of performing a heating operation and a
cooling operation for the passenger compartment; however, the
present invention may be applied to an air-conditioning
apparatus for a vehicle, capable of performing only a heating
operation for the passenger compartment. Also the present
invention may be employed as an engine warm-up apparatus for
--19--
CA 022144~6 1997-09-18
.
performing a quick warm-up of the water-cooled engine E
As the cooling water, there may be employed cooling
water to which an anti-freeze liquid such as ethylene glycol
solution is added, or coolant with which an anti-freeze liquid
or an anti-corrosion agent is mixed. Instead of cooling water,
oil as a thermal medium, or the refrigerant used in the
refrigeration cycle, or the like may be employed.
In the above-described embodiment, when the
electromagnetic clutch 4 (the electromagnetic clutch 31) is
off, e.g., the rotational speed of the rotor 9 is a
predetermined speed (0 r.p.m.), the high-viscosity oil moves
from the heat-generating chamber 48 into the oil storage
chamber 49; however, there may be employed a valve apparatus
for moving the high-viscosity oil in the heat-generating
chamber 48 into the oil storage chamber 49 when the rotational
speed of the rotor 9 is equal to or less than a predetermined
speed (e.g., 800 r.p.m.).
Although the present invention has been fully described
in connection with the preferred embodiments thereof with
reference to the accompanying drawings, it is to be noted that
various changes and modifications will become apparent to those
skilled in the art. Such changes and modifications are to be
understood as being included within the scope of the present
invention as defined in the appended claims.
-20-
