What is claimed is:
1. A heat exchanger in which a fluid flows to have a phase-change by performing a heat exchange with air passing through the heat exchanger, the heat exchanger comprising:
a plurality of tubes through which the fluid flows in a longitudinal direction of the tubes;
a plurality first header tanks for distributing and supplying refrigerant into the tubes, each of the first header tanks being disposed at one end side of each tube in the longitudinal direction; and
a plurality of second header tanks for collecting refrigerant from the tubes, each of the second header tanks being disposed at the remainder end side of each tube in the longitudinal direction, wherein:
the tubes and the first and second header tanks construct at least first through fourth heat-exchanging units for performing a heat exchange between fluid and air;
among the first through fourth heat-exchanging units, the first heat-exchanging unit and the second heat-exchanging unit are arranged in a line in a width direction approximately perpendicular to an air flowing direction, the third heat-exchanging unit and the fourth heat-exchanging unit are arranged in a line in the width direction, the first heat-exchanging unit and the fourth heat-exchanging unit are arranged in a line in the air flowing direction, and the second heat-exchanging unit and the third heat-exchanging unit are arranged in a line in the air flowing direction; and
the first through the fourth heat-exchanging units are disposed in such a manner that, a flow direction of fluid flowing through the tubes of the first heat-exchanging unit is opposite to that flowing through the tubes of the fourth heat-exchanging unit, the flow direction of fluid flowing through the tubes of the second heat-exchanging unit is opposite to that flowing through the tubes of the third heat-exchanging unit, the flow direction of fluid flowing in the first header tank of the first heat-exchanging unit is the same as that flowing in the first header tank of the fourth heat-exchanging unit, and the flow direction of fluid flowing in the first header tank of the second heat-exchanging unit is the same as that flowing in the first header tank of the third heat-exchanging unit.
2. The heat exchanger according to claim 1, wherein:
each of the tubes is disposed to extend in a vertical direction; and
each of the first and second header tanks is disposed to extend approximately in a horizontal direction perpendicular to the vertical direction.
3. The heat exchanger according to claim 1, wherein the first through fourth heat-exchanging units are disposed in such a manner that fluid passes through the third heat-exchanging unit and the fourth heat-exchanging unit after passing through the first heat-exchanging unit and the second heat-exchanging unit.
4. The heat exchanger according to claim 3, wherein the first heat-exchanging unit and the second heat-exchanging unit are disposed at downstream air sides of the fourth heat-exchanging unit and the third heat-exchanging unit, respectively.
5. The heat exchanger according to claim 1, wherein:
the first heat-exchanging unit has a fluid inlet from which refrigerant is introduced from an outer side, the fluid inlet is provided in the first heat-exchanging unit at a side adjacent to the second heat-exchanging unit;
the fourth heat-exchanging unit has a fluid outlet from which refrigerant is discharged to an outside, the fluid outlet is provided in the fourth heat-exchanging unit at a side adjacent to the third heat-exchanging unit; and
the first through fourth heat-exchanging units are disposed in such a manner that refrigerant flows through the first heat-exchanging unit, the second heat-exchanging unit, the third heat-exchanging unit and the fourth heat exchanging unit, in this order.
6. A heat exchanger according to claim 1, further comprising:
a plurality of corrugated fins each of which is disposed between adjacent tubes in the width direction.
7. A heat exchanger in which a fluid flows to perform a heat exchange with air passing through the heat exchanger, the heat exchanger comprising:
a plurality of tubes through which the fluid flows in a longitudinal direction of the tubes;
a plurality first header tanks for distributing and supplying refrigerant into the tubes, each of the first header tanks being disposed at the remainder end side of each tube in the longitudinal direction; and
a plurality of second header tanks for collecting refrigerant from the tubes, each of the second header tanks being disposed at the remainder end side of each tube in the longitudinal direction, wherein:
the tubes and the first and second header tanks construct at least first through fourth heat-exchanging units for performing a heat exchange between fluid and air;
among the first through fourth heat-exchanging units, the first heat-exchanging unit and the second heat-exchanging unit are arranged in a line in a width direction approximately perpendicular to an air flowing direction, the third heat-exchanging unit and the fourth heat-exchanging unit are arranged in a line in the width direction, the first heat-exchanging unit and the fourth heat-exchanging unit are arranged in a line in the air flowing direction, and the second heat-exchanging unit and the third heat-exchanging unit are arranged in a line in the air flowing direction; and
the first heat-exchanging unit has a fluid inlet from which refrigerant is introduced from an outer side, the fluid inlet is provided in the first heat-exchanging unit at a side adjacent to the second heat-exchanging unit;
the fourth heat-exchanging unit has a fluid outlet from which refrigerant is discharged to an outside, the fluid outlet is provided in the fourth heat-exchanging unit at a side adjacent to the third heat-exchanging unit; and
the first through fourth heat-exchanging units are disposed in such a manner that refrigerant flows through the first heat-exchanging unit, the second heat-exchanging unit, the third heat-exchanging unit and the fourth heat exchanging unit, in this order.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An engine starting apparatus comprising:
a driven gear connected to an engine;
a starter motor adapted to be driven to rotate when said engine is started;
a speed-reduction and power-cut-off mechanism connected to said starter motor and having a rotatable output shaft, said speed-reduction and power-cut-off mechanism being adapted to output a rotation of said starter motor from said output shaft while reducing the rotational speed of the starter motor and to cut off power transmission between said starter motor and said output shaft when the rotational speed of said output shaft exceeds the reduced rotational speed of the starter motor;
a drive gear provided on said output shaft in such a manner as to be rotatable together with said output shaft and to move axially over said output shaft between an engagement position where said drive gear is brought into mesh engagement with said driven gear and a disengagement position where said drive gear is brought out of engagement with said driven gear; and
a driving unit driving said drive gear to said engagement position when said engine is started and to said disengagement position after said engine has been started.
2. The engine starting apparatus according to claim 1, wherein said speed-reduction and power-cut-off mechanism is constituted by a wedge roller type speed reduction mechanism.
3. The engine starting apparatus according to claim 2, wherein said wedge roller type speed reduction mechanism including a plurality of rollers rotatably disposed around a rotational shaft of the starter motor; and an rotatable output shaft having an outer ring disposed around said plurality of rollers, said rotational shaft being offset from a rotational center of said outer ring, one of said wedge rollers being movable between said rotational shaft and said outer ring so as to provide a wedge action for power transmission between said starter motor and said output shaft.
4. The engine starting apparatus according to claim 3, wherein said plurality of rollers are brought into abutment with said rotational shaft and said output ring via an oil film being interposed therebetween.
5. An engine starting apparatus comprising:
a driven gear connected to an engine;
a starter motor having a rotational shaft being driven to rotate when said engine is started;
a speed-reduction and power-cut-off mechanism having a plurality of rollers rotatably disposed around the rotational shaft of the starter motor; and an rotatable output shaft having an outer ring disposed around said plurality of rollers, said rotational shaft being offset from a rotational center of said outer ring, one of said wedge rollers being movable between the rotational shaft and said outer ring so as to provide a wedge action for power transmission between said starter motor and said output shaft;
a drive gear provided on said output shaft in such a manner as to be rotatable together with said output shaft and to move axially over said output shaft between an engagement position where said drive gear is brought into mesh engagement with said driven gear and a disengagement position where said drive gear is brought out of engagement with said driven gear; and
a driving unit driving said drive gear to said engagement position when said engine is started and to said disengagement position after said engine has been started.
6. The engine starting apparatus according to claim 5, wherein said plurality of rollers are brought into abutment with said rotational shaft and said output ring via an oil film being interposed therebetween.