초록 ▼

A small self-propelled loader has hydraulic drive motors and at least one work cylinder, and has a hydraulic system that efficiently utilizes the available horse power from an internal combustion engine on the loader. The engine drives a tandem pump and the flows from two sections of the tandem pump

A small self-propelled loader has hydraulic drive motors and at least one work cylinder, and has a hydraulic system that efficiently utilizes the available horse power from an internal combustion engine on the loader. The engine drives a tandem pump and the flows from two sections of the tandem pump pass through a first diverter valve that permits using the flow from each of the pump sections to drive a respective one of the drive motors. The return or drain flow from valves controlling the drive motors is connected to a second diverter valve to selectively direct the drain flow from the drive motors for operating remote work cylinders. Alternately, the first diverter valve directs the output from one pump section to the work cylinders, so that when the loader is standing still or moving very slowly, the work cylinder has adequate flow, and flow from the other pump section is split to power the drive motors. The motors and work cylinders are connected to separate relief valves so that a higher working pressure is available for the drive motors.

대표청구항 ▼

A small self-propelled loader has hydraulic drive motors and at least one work cylinder, and has a hydraulic system that efficiently utilizes the available horse power from an internal combustion engine on the loader. The engine drives a tandem pump and the flows from two sections of the tandem pump

A small self-propelled loader has hydraulic drive motors and at least one work cylinder, and has a hydraulic system that efficiently utilizes the available horse power from an internal combustion engine on the loader. The engine drives a tandem pump and the flows from two sections of the tandem pump pass through a first diverter valve that permits using the flow from each of the pump sections to drive a respective one of the drive motors. The return or drain flow from valves controlling the drive motors is connected to a second diverter valve to selectively direct the drain flow from the drive motors for operating remote work cylinders. Alternately, the first diverter valve directs the output from one pump section to the work cylinders, so that when the loader is standing still or moving very slowly, the work cylinder has adequate flow, and flow from the other pump section is split to power the drive motors. The motors and work cylinders are connected to separate relief valves so that a higher working pressure is available for the drive motors. o claim 1, wherein said each of said side covers includes a protrusion surrounding a respective said hole, with said protrusion of one of said each of said side covers facing said protrusion of another of said each of said side covers and being spaced therefrom by a distance that is substantially equal to a distance between outer surfaces of pin links of the roller chain. 6. The chain cover according to claim 1, wherein, said top cover includes a first extension extending beyond one of said each of said side covers, and a second extension extending beyond another of said each of said side covers. 7. A combination of a chain cover and a roller chain, said roller chain having roller links and a coupling pin, said chain cover comprising: a top cover covering a top portion of said roller chain, said top cover having a length that is substantially equal to a pitch of said roller chain and being supported by said roller links; and side covers covering side portions of said roller chain, each of said side covers extending from a respective end of said top cover and having (i) a hole receiving said coupling pin, said hole having a first end and a second end, (ii) a convex arcuate front edge that is concentric with said hole, (iii) a concave arcuate rear edge, and (iv) a guide portion beneath said hole, said guide portion having (a) an inner surface and an outer surface, with said inner surface being angled in a direction from said first end of said hole toward said outer surface, (b) a front end and a rear end, and (c) a bottom surface. 8. The combination according to claim 7, wherein said bottom surface is planar and parallel to said top cover, with a first distance from a center of said hole to said bottom surface, and a second distance from said rear end to a line extending through the center of said hole, each being substantially equal to about one half the pitch of said roller chain, said first distance and said second distance being orthogonal to each other. 9. The combination according to claim 8, wherein said roller chain further has pin links positioned outwardly of said roller links, respectively, and said each of said side covers includes a protrusion surrounding a respective said hole, with said protrusion of one of said each of said side covers contacting one of said pin links, and said protrusion of another of said each of said side covers contacting another of said pin links. 10. The combination according to claim 8, wherein, said top cover includes a first extension extending beyond one of said each of said side covers, and a second extension extending beyond another of said each of said side covers. 11. The combination according to claim 7, wherein said roller chain further has pin links positioned outwardly of said roller links, respectively, and said each of said side covers includes a protrusion surrounding a respective said hole, with said protrusion of one of said each of said side covers contacting one of said pin links, and said protrusion of another of said each of said side covers contacting another of said pin links. 12. The combination according to claim 7, wherein, said top cover includes a first extension extending beyond one of said each of said side covers, and a second extension extending beyond another of said each of said side covers. 13. The combination according to claim 7, wherein said roller chain further has additional roller links and an additional coupling pin, and further comprising an additional chain cover, said additional chain cover comprising: a top cover covering another top portion of said roller chain, said top cover having a length that is substantially equal to the pitch of said roller chain and being supported by said additional roller links; and side covers covering other side portions of said roller chain, each of said side covers extending from a respective end of said top cover and having (i) a hole receiving said additi onal coupling pin, said hole having a first end and a second end, (ii) a convex arcuate front edge that is concentric with said hole, (iii) a concave arcuate rear edge, and (iv) a guide portion beneath said hole, said guide portion having (a) an inner surface and an outer surface, with said inner surface being angled in a direction from said first end of said hole toward said outer surface, (b) a front end and a rear end, and (c) a bottom surface, with said chain cover and said additional chain cover being immediately adjacent one another and substantially identical to one another. 14. The combination according to claim 13, wherein said bottom surface of said guide portion of said each of said side covers of said additional chain cover is planar and parallel to said top cover of said additional chain cover, with a first distance from a center of said hole of said each of said side covers of said additional chain cover to said bottom surface, and a second distance from said rear end of said guide portion of said each of said side covers of said additional chain cover to a line extending through the center of said hole, each being substantially equal to about one half the pitch of said roller chain, said first distance and said second distance being orthogonal to each other. 15. The combination according to claim 14, wherein said roller chain further has additional pin links positioned outwardly of said additional roller links, respectively, and said each of said side covers of said additional chain cover includes a protrusion surrounding a respective said hole of said each of said side covers of said additional chain cover, with said protrusion of one of said each of said side covers contacting one of said additional pin links, and said protrusion of another of said each of said side covers contacting another of said additional pin links. 16. The combination according to claim 14, wherein, said top cover of said additional chain cover includes a first extension extending beyond one of said each of said side covers of said additional chain cover, and a second extension extending beyond another of said each of said side covers. 17. The combination according to claim 13, wherein said roller chain further has additional pin links positioned outwardly of said additional roller links, respectively, and said each of said side covers of said additional chain cover includes a protrusion surrounding a respective said hole of said each of said side covers of said additional chain cover, with said protrusion of one of said each of said side covers contacting one of said additional pin links, and said protrusion of another of said each of said side covers contacting another of said additional pin links. 18. The combination according to claim 13, wherein, said top cover of said additional chain cover includes a first extension extending beyond one of said each of said side covers of said additional chain cover, and a second extension extending beyond another of said each of said side covers.