초록 ▼

This invention is directed to an external loop nonfreezing heat exchanger for cooling a heat transfer fluid with cryogenic fluid. The cryogenic fluid is first pre-vaporized with the spent cryogenic fluid. The heat transfer fluid is then cooled by the vaporized cryogenic fluid instead of the cryogeni

This invention is directed to an external loop nonfreezing heat exchanger for cooling a heat transfer fluid with cryogenic fluid. The cryogenic fluid is first pre-vaporized with the spent cryogenic fluid. The heat transfer fluid is then cooled by the vaporized cryogenic fluid instead of the cryogenic fluid feed directly.

대표청구항 ▼

This invention is directed to an external loop nonfreezing heat exchanger for cooling a heat transfer fluid with cryogenic fluid. The cryogenic fluid is first pre-vaporized with the spent cryogenic fluid. The heat transfer fluid is then cooled by the vaporized cryogenic fluid instead of the cryogeni

This invention is directed to an external loop nonfreezing heat exchanger for cooling a heat transfer fluid with cryogenic fluid. The cryogenic fluid is first pre-vaporized with the spent cryogenic fluid. The heat transfer fluid is then cooled by the vaporized cryogenic fluid instead of the cryogenic fluid feed directly. traction drive for propelling the reel mower frame across the ground, the traction drive being powered by the power source; (d) a reel cutting unit carried on the reel mower frame, the reel cutting unit having a cutting reel which is rotatable about a substantially horizontal, transverse axis which reel cooperates with a bedknife to cut grass; (e) a reel drive for powering the cutting reel, the reel drive being powered by the power source; and (f) a single control handle carried on the handle assembly for selectively controlling the operation of both the traction drive and the reel drive, wherein the control handle rotates back and forth about a substantially horizontal pivot pin to control the operation of a first drive comprising one of the traction drive and the reel drive, and wherein the control handle includes a displaceable toggle which can be pivoted back and forth about another pivot pin to displace the toggle from a first position in which the toggle is aligned with the control handle to a second position in which the toggle is bent out of alignment with the control handle, the toggle controlling the operation of a second drive comprising the other of the traction drive and the reel drive. 4. The walk reel mower of claim 3, wherein the control handle controls the operation of the traction drive and the toggle controls the operation of the reel drive. 5. The walk reel mower of claim 3, wherein the toggle is connected to a reciprocal rod extending through the control handle such that displacing the toggle moves the reciprocal rod relative to the control handle, wherein the toggle in the second position thereof moves the reciprocal rod into a position to additionally couple the control handle to the reel drive so that pivoting motion of the control handle about the first pivot pin then actuates both the traction and reel drives. 6. The walk reel mower of claim 3, wherein the toggle is carried at the top of the control handle. 7. The walk reel mower of claim 3, wherein the toggle is laterally displaceable relative to the control handle such that the toggle in the second position thereof is bent to one side of the control handle. 8. The walk reel mower of claim 5, further including a first cable or linkage connected to the control handle, wherein the first cable or linkage is also operatively connected to the first drive such that the first drive is actuated by the first cable or linkage as the control handle pivots about the first pivot pin. 9. The walk reel mower of claim 8, further including a second cable or linkage connected to a pivotal link, the pivotal link not being connected to the control handle link when the toggle is in the first position thereof such that the pivotal link remains stationary during pivotal motion of the control handle about the first pivot pin when the toggle is in the first position thereof, wherein the toggle in the second position thereof moves the reciprocal rod into a notch in the pivotal link to mechanically couple the pivotal link to the control handle such that pivotal motion of the control handle about the first pivot pin also pivots the pivotal link when the toggle is in the second position thereof, the second cable or linkage being operatively connected to the second drive such that the second drive is actuated by the second cable or linkage when the pivotal link is mechanically coupled to the control handle and the control handle is pivoted about the first pivot pin. 10. The walk reel mower of claim 9, wherein the first drive is the traction drive and the second drive is the reel drive. 11. A walk reel mower, which comprises: (a) a reel mower frame on which a power source is carried; (b) an upwardly extending handle assembly connected at its lower end to the reel mower frame, the handle assembly including a portion which the operator can grip to guide the reel mower frame while the operator walks behind the reel mower frame; (c) a traction drive for propelling the reel