Hydraulic unit with integral oil cooler
View Patent ↗A hydraulic unit including an integrated fluid cooler. The fluid cooler includes a flow-through type heat exchanger. The hydraulic unit can include a pump, a motor, or both a pump and a motor. The fluid cooler can be carried by a housing of the hydraulic unit and a fan for moving air through the fluid cooler and circulating air over at least a portion of the housing of the hydraulic unit can be interposed between the fluid cooler and the housing. The fluid cooler can also be configured to function as a fan shroud. Fluid from the hydraulic unit as well as fluid from other sources can be circulated through the fluid cooler.
1. A hydraulic unit comprising:
a hydraulic pump and/or motor having a housing;
a fluid cooler including a flow-through heat exchanger spaced apart from the housing for cooling fluid associated with the hydraulic pump and/or motor; and
a fan positioned to cause air to flow through the fluid cooler and pass over at least a portion of the housing;
wherein the fluid cooler is carried by the housing;
wherein the hydraulic unit is a hydrostatic transmission including both a hydraulic pump and a hydraulic motor.
2. A hydraulic unit as set forth in claim 1 , wherein the pump or motor has a rotatably driven shaft to which the fan is mounted for rotation therewith.
3. A hydraulic unit as set forth in claim 1 , wherein the hydrostatic transmission is an integrated hydrostatic transmission having the hydraulic pump and hydraulic motor disposed within the housing.
4. A hydraulic unit as set forth in claim, 1 , wherein the flow-through heat exchanger has opposite sides and a plurality of through apertures through which air can flow from one side to the other.
5. A hydraulic unit as set forth in claim 1 , wherein the fan is configured to draw air through the fluid cooler.
6. A hydraulic unit as set forth in claim 1 , wherein the fan is configured to push air through the fluid cooler.
7. A hydraulic unit as set forth in claim 1 , wherein the flow-through heat exchanger is a manifold-type heat exchanger having an inlet manifold, an outlet manifold, and a plurality of flow passages through which fluid can flow from the inlet manifold to the outlet manifold.
8. A hydraulic unit as set forth in claim 7 , further comprising a plurality of fins radiating from an external surface of the plurality of flow passages.
9. A hydraulic unit comprising:
a hydraulic pump and/or motor having a housing;
a fluid cooler including a flow-through heat exchanger spaced apart from the housing for cooling fluid associated with the hydraulic pump and/or motor; and
a fan positioned to cause air to flow through the fluid cooler and pass over at least a portion of the housing; and
a fan shroud including the fluid cooler;
wherein the fluid cooler is interposed between the fan and the housing.
10. A lawn mower including a frame to which at least one drive wheel is mounted, and a hydraulic unit mounted to the frame and operatively drivingly coupled to the drive wheel, wherein the hydraulic unit includes
a hydraulic pump and/or motor having a housing;
a fluid cooler including a flow-through heat exchanger spaced apart from the housing for cooling fluid associated with the hydraulic pump and/or motor; and
a fan positioned to cause air to flow through the fluid cooler and pass over at least a portion of the housing; and
a fan shroud including the fluid cooler.
11. A hydraulic unit comprising:
a hydraulic pump and/or motor having a housing;
a fluid cooler including a flow-through heat exchanger spaced apart from the housing for cooling fluid associated with the hydraulic pump and/or motor; and
a fan positioned to cause air to flow through the fluid cooler and pass over at least a portion of the housing; and
a fan shroud including the fluid cooler, and further comprising at least one bracket for supporting the fluid cooler, the bracket extending between the housing and the fluid cooler.
12. A hydraulic unit as set forth in claim 11 , wherein the fluid cooler and at least one bracket together form a fan shroud covering at least part of the fan.