초록 ▼

A dual pump apparatus for use on a vehicle or industrial application having a housing in which a pair of hydraulic pumps are mounted, having a cooling fan mounted on the primary or secondary input shaft on the opposite side of the pulley used to engage the prime mover. A charge pump may be mounted o

A dual pump apparatus for use on a vehicle or industrial application having a housing in which a pair of hydraulic pumps are mounted, having a cooling fan mounted on the primary or secondary input shaft on the opposite side of the pulley used to engage the prime mover. A charge pump may be mounted on the end cap, and the trunnion arms for controlling the hydraulic pumps extend out of opposite sides of the housing. An auxiliary pump may also be mounted on the primary input shaft and may be located either at the input end thereof adjacent to the pulley, or on the opposite side of the housing.

대표청구항 ▼

The invention claimed is: 1. A hydraulic apparatus comprising: a hydraulic mounting member having a first end, a second end formed opposite the first end and a pair of sides connecting the first and second ends; a first hydraulic pump and a second hydraulic pump both rotatably mounted on the hydrau

The invention claimed is: 1. A hydraulic apparatus comprising: a hydraulic mounting member having a first end, a second end formed opposite the first end and a pair of sides connecting the first and second ends; a first hydraulic pump and a second hydraulic pump both rotatably mounted on the hydraulic mounting member; and a pair of system passages formed in and extending through the hydraulic mounting member from the first end to the second end, each system passage comprising a first port in fluid communication with the first hydraulic pump and an opening on the first end of the hydraulic mounting member and a second port in fluid communication with the second hydraulic pump and an opening on the second end of the hydraulic mounting member. 2. The hydraulic apparatus of claim 1, further comprising a bypass valve passage extending into one of the sides of the hydraulic mounting member generally perpendicular to the pair of system passages and intersecting both of the pair of system passages; and a bypass valve located in the bypass valve passage. 3. The hydraulic apparatus of claim 2, further comprising: a gallery located in the hydraulic mounting member between the pair of system passages; and a first pair of check valves located on one of the sides of the hydraulic mounting member and a second pair of check valves located on the other side of the hydraulic mounting member generally opposite the first side, wherein one of the check valves in each pair of check valves is located on an opposite side of the bypass valve from the other of the check valves. 4. The hydraulic apparatus of claim 3, wherein the bypass valve passage is generally located at the midpoint of one of the sides of the hydraulic mounting member between the first end and the second end thereof. 5. The hydraulic apparatus of claim 2, wherein the bypass valve comprises a plurality of flow passages formed therein, whereby when the bypass valve is actuated fluid is provided a route to flow from both system passages into the bypass valve passage. 6. The hydraulic apparatus of claim 5, wherein the flow passages hydraulically connect both system passages when the bypass valve is actuated. 7. The hydraulic apparatus of claim 2, wherein each system passage comprises a channel portion connecting the first port to the second port, wherein the diameter of the channel portion is smaller than the diameter of the first and second ports. 8. The hydraulic apparatus of claim 7, wherein the bypass valve passage intersects both channel portions. 9. The hydraulic apparatus of claim 2, wherein the bypass valve passage intersects the first system passage and the second system passage so that each system passage is separated into two generally equal portions. 10. A hydraulic apparatus comprising: a hydraulic mounting member having a width and a length; at least two pump running surfaces on the hydraulic mounting member; a pair of hydraulic system passages formed in, and extending the length of, the hydraulic mounting member; a bypass valve passage formed in the hydraulic mounting member near the center of the hydraulic mounting member length, the bypass valve passage extending generally perpendicular to and intersecting both of the system passages, whereby the bypass valve passage separates each of the system passages into two port portions; and a bypass valve located in the bypass valve passage. 11. The hydraulic apparatus of claim 10, further comprising a gallery passage formed in the hydraulic mounting member generally parallel to and located between the pair of system passages; and a plurality of check valves located in the hydraulic mounting member, wherein at least one check valve of the plurality of check valves operatively connects the gallery and each of the port portions. 12. The hydraulic apparatus of claim 11, wherein the gallery contains an inlet to receive fluid from a charge pump and a relief passage to allow excess fluid to escape from the gallery. 13. The hydraulic apparatus of claim 11, wherein the bypass valve extends through the gallery and a fluid path is formed around the bypass valve at the location where the bypass valve extends through the gallery. 14. The hydraulic apparatus of claim 11, wherein each check valve is spring biased to a closed position. 15. The hydraulic apparatus of claim 11, wherein at least one of the check valves comprises a bleed extending between the gallery and a port portion. 16. A hydraulic apparatus comprising: a hydraulic mounting member having a first end, a second end formed opposite the first end and a pair of sides connecting the first and second ends; a first hydraulic pump and a second hydraulic pump both rotatably mounted on the mounting member; and a first pair of system ports open on the first end of the mounting member and in fluid communication with the first hydraulic pump; a second pair of system ports open on the second end of the mounting member and in fluid communication with the second hydraulic pump; a gallery located in the mounting member between the two ports in either the first pair of system ports or the second pair of system ports; and a first pair of check valves located on one of the sides of the mounting member, and a second pair of check valves located on the other side of the mounting member, wherein one of each pair of check valves is in fluid communication with one of the first pair of system ports and the other of each pair of check valves is in fluid communication with one of the second pair of system ports. 17. The hydraulic apparatus of claim 16, further comprising a first channel formed in the mounting member between one of the first pair of system ports and one of the second pair of system ports, and a second channel formed in the mounting member between the other of the first pair of system ports and the other of the second pair of system ports. 18. A hydraulic apparatus comprising: a hydraulic mounting member having a first end, a second end formed opposite the first end and a pair of sides connecting the first and second ends; a first hydraulic pump and a second hydraulic pump both rotatably mounted on the mounting member; and a first pair of system ports open on the first end of the mounting member and in fluid communication with the first hydraulic pump; a second pair of system ports open on the second end of the mounting member and in fluid communication with the second hydraulic pump; a gallery located in the mounting member; and a first pair of check valves located on one of the sides of the mounting member, and a second pair of check valves located on the other side of the mounting member, wherein one of each pair of check valves is in fluid communication with one of the first pair of system ports and the other of each pair of check valves is in fluid communication with one of the second pair of system ports. 19. The hydraulic apparatus of claim 18, further comprising a bypass valve passage extending into one of the sides of the mounting member generally perpendicular to both the first and second pairs of system ports, and a bypass valve located in the bypass valve passage. 20. The hydraulic apparatus of claim 19, wherein the first check valve in each pair of check valves is located on an opposite side of the bypass valve from the second check valve in each pair. 21. The hydraulic apparatus of claim 18, wherein the gallery contains an inlet to receive fluid from a charge pump and a relief passage to allow excess fluid to escape from the gallery. 22. The hydraulic apparatus of claim 18, further comprising a first channel formed in the mounting member between one of the first pair of system ports and one of the second pair of system ports, and a second channel formed in the mounting member between the other of the first pair of system ports and the other of the second pair of system ports. 23. The hydraulic apparatus of claim 1, further comprising a pair of valve plates, each valve plate disposed between one of the hydraulic pumps and the hydraulic mounting member. 24. The hydraulic apparatus of claim 18, further comprising a pair of valve plates, each valve plate disposed between one of the hydraulic pumps and the mounting member.