External cooling circuit and adapter for use with integrated hydrostatic transaxle
An external cooling circuit for an integrated transaxle includes an integrated transaxle having a casing and a motor and a pump contained within the casing. The pump is connected to and actuable by an input shaft extending from the casing. The motor is connected to an output shaft extending from the casing. Hydraulic fluid is circulated in the casing by the pump to drive the motor. First and second ports are formed in the casing and a charge pump is contained within the casing. A reservoir is external to the casing. The reservoir is in fluid communication with the first and second ports of the casing such that the charge pump is configured to create a vacuum at the second port to cause hydraulic fluid to exit the casing through the first port, enter the reservoir, and re-enter the casing through the second port.
1. An external cooling circuit for an integrated transaxle, comprising:
an integrated transaxle having:
a casing,
a motor and a pump contained within the casing, the pump being connected to and actuable by an input shaft extending from the casing, the motor being connected to an output shaft extending from the casing
hydraulic fluid circulated in the casing by the pump to drive the motor,
first and second ports formed in the casing, and
a charge pump contained within the casing; and
a reservoir external to the casing, the reservoir being in separate fluid communication with the each of the first and second ports of the casing such that the charge pump is configured to create a vacuum at the second port to cause hydraulic fluid to exit the casing through the first port, enter the reservoir, and re-enter the casing through the second port.
2. The external cooling circuit of claim 1 , wherein the second port includes an opening in a wall of the casing and an open-ended passage concentrically arranged within the opening and in fluid communication with the charge pump.
3. The external cooling circuit of claim 2 , further comprising:
an adapter configured to be removably attached to the second port and having a fitting for removable attachment to a conduit in fluid communication with the reservoir, the fitting being in fluid communication with a central axial bore of the adapter, the adapter including a receptacle that mounts to the open end of the passage of the second port.
4. The external cooling circuit of claim 3 , wherein the adapter includes first and second plates connected to each other and rotatable with respect to each other about a rotation axis passing through the central axial bore of the adapter, the second plate including the fitting, which extends through a central axial opening in the first plate.
5. The external cooling circuit of claim 4 , wherein the first plate includes at least one peripheral axially extending channel radially spaced apart from the central opening and the second plate includes at least one complementary peripheral axially extending channel radially spaced apart from the fitting, wherein the at least one peripheral channel of the first plate is alignable with the at least one corresponding peripheral channel of the second plate via relative rotation of the first and second plates, and wherein when the adapter is connected to the second port, the at least one peripheral channel of the second plate is in fluid communication with the opening of the wall of the casing.
6. The external cooling circuit of claim 5 , further comprising a filter mounted to the adapter such that a filter media is arranged in a flow path of hydraulic fluid between the at least one peripheral channel of the first plate and the fitting.
7. The external cooling circuit of claim 2 , further comprising:
a filter having a filter media; and
an adapter configured to be removably attached to the second port, the adapter having a central hollow cavity, a radial inlet in fluid communication with the hollow cavity, and a fitting extending axially through the hollow cavity and configured for mounting to the open end of the passage of the second port, the filter being removably attached to the fitting such that the filter media is arranged in a flow path of hydraulic fluid between the hollow cavity and the fitting.
8. The external cooling circuit of claim 1 , further comprising:
a cooler external to the casing, the cooler being connected between, and in fluid communication with, the first port and the reservoir.
9. The external cooling circuit of claim 8 , wherein the cooler is a heat exchanger.
10. The external cooling circuit of claim 1 , further comprising:
a filter arranged external to the casing, the filter being connected between, and in fluid communication with, the reservoir and the second port.
11. The external cooling circuit of claim 1 , wherein the first port is an overflow port of the integrated transaxle and the second port is a filter port of the integrated transaxle.
12. An adapter for use with an external cooling circuit of an integrated transaxle and a filter, the integrated transaxle having a casing and a filter port, the filter port including an opening in a wall of the casing and an open-ended passage concentrically arranged within the opening and in fluid communication with a charge pump, the adapter comprising:
a first plate with an axially extending central opening;
a second plate connected to the first plate and rotatable with respect to the first plate about a rotation axis passing longitudinally through the central opening of the first plate;
a fitting extending from the second plate and passing through the central opening of the first plate;
at least one first peripheral axially extending channel arranged in the first plate and radially spaced apart from the central opening; and
at least one second peripheral axially extending channel arranged in the second plate and radially spaced apart from the fitting, the at least one first peripheral channel being alignable with the at least one second peripheral channel via relative rotation of the first and second plates.
13. The adapter of claim 12 , wherein the second plate includes at least one O-ring arranged on a surface of the second plate facing the first plate, the at least one O-ring being in contact with the first plate and surrounding the at least one second peripheral channel.
14. The adapter of claim 12 , further comprising an O-ring surrounding the at least one second peripheral channel and the fitting, and being arranged on a surface of the second plate facing away from the first plate.
15. The adapter of claim 12 , wherein the fitting is threaded at an end extending away from the first plate.
16. The adapter of claim 12 , further comprising a nut that surrounds the fitting and is arranged at a surface of the first plate facing away from the second plate.
17. An external cooling circuit for an integrated transaxle, comprising:
an integrated transaxle having:
a casing,
a motor and a pump contained within the casing, the pump being connected to and actuable by an input shaft extending from the casing, the motor being connected to an output shaft extending from the casing
hydraulic fluid circulated in the casing by the pump to drive the motor,
first and second ports formed in the casing, and
a charge pump contained within the casing, the second port including an opening in a wall of the casing and an open-ended passage concentrically arranged within the opening and in fluid communication with the charge pump;
a reservoir external to the casing, the reservoir being in fluid communication with the first and second ports of the casing such that the charge pump is configured to create a vacuum at the second port to cause hydraulic fluid to exit the casing through the first port, enter the reservoir, and re-enter the casing through the second port; and
an adapter configured to be removably attached to the second port and having a fitting for removable attachment to a conduit in fluid communication with the reservoir, the fitting being in fluid communication with a central axial bore of the adapter, the adapter including a receptacle that mounts to the open end of the passage of the second port,
wherein the adapter includes first and second plates connected to each other and rotatable with respect to each other about a rotation axis passing through the central axial bore of the adapter, the second plate including the fitting, which extends through a central axial opening in the first plate.
18. The external cooling circuit of claim 17 , wherein the first plate includes at least one peripheral axially extending channel radially spaced apart from the central opening and the second plate includes at least one complementary peripheral axially extending channel radially spaced apart from the fitting, wherein the at least one peripheral channel of the first plate is alignable with the at least one corresponding peripheral channel of the second plate via relative rotation of the first and second plates, and wherein when the adapter is connected to the second port, the at least one peripheral channel of the second plate is in fluid communication with the opening of the wall of the casing.
19. The external cooling circuit of claim 18 , further comprising a filter mounted to the adapter such that a filter media is arranged in a flow path of hydraulic fluid between the at least one peripheral channel of the first plate and the fitting.
20. An external cooling circuit for an integrated transaxle, comprising:
an integrated transaxle having:
a casing,
a motor and a pump contained within the casing, the pump being connected to and actuable by an input shaft extending from the casing, the motor being connected to an output shaft extending from the casing
hydraulic fluid circulated in the casing by the pump to drive the motor,
first and second ports formed in the casing, and
a charge pump contained within the casing, the second port including an opening in a wall of the casing and an open-ended passage concentrically arranged within the opening and in fluid communication with the charge pump;
a reservoir external to the casing, the reservoir being in fluid communication with the first and second ports of the casing such that the charge pump is configured to create a vacuum at the second port to cause hydraulic fluid to exit the casing through the first port, enter the reservoir, and re-enter the casing through the second port;
a filter having a filter media; and
an adapter configured to be removably attached to the second port, the adapter having a central hollow cavity, a radial inlet in fluid communication with the hollow cavity, and a fitting extending axially through the hollow cavity and configured for mounting to the open end of the passage of the second port, the filter being removably attached to the fitting such that the filter media is arranged in a flow path of hydraulic fluid between the hollow cavity and the fitting.