| 摘要 |
744.493. Earth-excavating apparatus. METROPOLITAN WATER BOARD. April 28. 1954 [April 28, 1953], No. 11750/53. Class 68(1 ) Apparatus for excavating the surface layer of material over which it travels comprises an endless track vehicle on the front of which is pivotally mounted forwardly-projecting arms carrying a scraper blade-supporting structure 40. On a shaft 18, mounted in the end portions of the structure 40 are oppositely handed screw conveyers 22, which feed the material scraped up by the blade or blades 41 towards the centre of the structure 40 into the path of a bucket conveyer 20, 21. The material is lifted by the conveyer 21. 22 through trunking 14 and is discharged down a shoot 15 onto a conveyer 36 by which it is discharged clear of the machine. The scraper blade or blades 41 and associated conveyer assemblies are vertically adjusted by screw means 27-33 to maintain a given cutting depth. The blade or blades 41. may be pivotally mounted on the structure 40 and have an adjustable plate 42 secured at an angle to and at some distance from the leading edge of the blade to prevent the blades digging downwards into the sand. |
