Claims
- 1. A heating system for the sole plate of a screed on an asphalt paving machine comprising:
- a tractor;
- an internal combustion engine on said tractor powering the tractor, said engine having an exhaust system;
- a screed coupled to said tractor, said screed having a sole plate;
- a first heat exchanger in said exhaust system;
- a second heat exchanger on said sole plate; and
- circulating means for circulating liquid between said heat exchangers and thereby transferring heat from said exhaust system to said sole plate.
- 2. A heating system according to claim 1 in which said first heat exchanger comprises a coil around an exhaust pipe in said exhaust system of the internal combustion engine.
- 3. A heating system according to claim 1 in which said circulating means includes a pump taking suction from a reservoir connected to said first heat exchanger, said pump discharging heated liquid under pressure to said second heat exchanger, and said second heat exchanger in turn discharging said liquid for return to said first heat exchanger for reheating after heat transfer in said second heat exchanger.
- 4. A heating system for the sole plate of a screed on an asphalt paving machine comprising:
- a tractor;
- an internal combustion engine on said tractor powering the tractor, said engine having an exhaust system;
- a screed coupled to said tractor, said screed having a sole plate;
- a heat exchanger having a heat exchange tube mounted directly on said sole plate for receiving a heated liquid; and
- heat transfer means for heating a liquid from heat in said exhaust system and circulating the heated liquid through said heat exchange tube.
- 5. A heating system according to claim 4 in which said heat transfer means includes a second heat exchanger in said exhaust system and a pump for circulating liquid between said heat exchangers.
- 6. A heating system according to claim 5 in which said second heat exchanger includes a tube coiled around an exhaust pipe in said exhaust system.
- 7. A heating system according to claim 5 in which said pump is driven by a hydraulic motor which in turn is driven by pressurized fluid circulated by a second pump driven by said engine.
- 8. A heating system in an asphalt paving machine comprising:
- a tractor;
- an internal combustion engine on said tractor powering the tractor, said engine having an exhaust system;
- a main screed coupled to said tractor;
- extender screeds mounted on said main screed;
- sole plates on said screeds;
- a first heat exchanger in said exhaust system;
- additional heat exchangers on said sole plates of the main screed and extender screeds; and
- circulating means for circulating liquid between said first heat exchanger and said additional heat exchangers and thereby transferring heat from said exhaust system to said sole plates.
- 9. A heating system according to claim 8 in which said circulating means includes a circulating pump driven by a hydraulic motor, and a hydraulic circuit including a hydraulic pump driven by said engine and including said hydraulic motor, whereby said circulating pump is powered by energy derived from said engine.
- 10. A combination heating system and vibratory system for a screed coupled to a tractor on an asphalt paving machine comprising:
- a tractor;
- a screed coupled to said tractor and having a sole plate;
- an internal combustion engine powering said tractor and having an exhaust system including a first heat exchanger for heating circulating liquid by the exhaust heat from the engine;
- a screed-heating hydraulic circuit including a second heat exchanger on said screed for heating the sole plate of the screed, and including a circulation pump for circulating heating liquid between said heat exchangers,
- a hydraulic motor coupled to said circulation pump;
- a vibratory unit on the screed driven by a second hydraulic motor;
- and a pressurized liquid supply circuit to said hydraulic motors including a primary pump on said tractor driven by said engine.
- 11. A system according to claim 10 in which said second heat exchanger includes heat exchange tubes in direct engagement with said sole plate, said heating liquid passing through said tubes.
- 12. A method for heating a sole plate of a screed coupled to a tractor on an asphalt paving machine, said tractor having an internal combustion engine powering the tractor, said method comprising:
- transferring heat from the exhaust gases of said engine to a liquid;
- circulating the heated liquid to said screed;
- and transferring heat from said heated liquid to said sole plate.
- 13. A method according to claim 12 in which said liquid is continuously circulated in a closed loop system between a first heat exchanger transferring heat from said exhaust gases to said liquid and a second heat exchanger on said sole plate for transferring heat to the sole plate.
Parent Case Info
This application is a continuation-in-part of U.S. patent application Ser. No. 07/847,648 filed Mar. 3, 1992, now U.S. Pat. No. 5,259,693, as a continuation-in-part of U.S. patent application Ser. No. 07/577,615 dated Sep. 4, 1990, now U.S. Pat. No. 5,096,331.
US Referenced Citations (9)
Continuation in Parts (2)
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Number |
Date |
Country |
Parent |
847648 |
Mar 1992 |
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Parent |
577615 |
Sep 1990 |
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