| 摘要 |
1,064,735. Grinding; drilling machine details. UNION TANK CAR CO. Dec. 12, 1963 [Dec. 26, 1962], No. 49112/63. Headings B3B, B3C and B3D. [Also in Division F1] Apparatus for cutting a hole in a body, such as a sewer main, comprises a first, rigid, support member having body-engaging portions adapted to span the body, fastener means adapted to be releasably connected to the portions and to surround the body so as to secure the first support member firmly to the body, a second rigid support member, drive means supported on the second support member and adapted to drive a cutting tool, piston and cylinder means connected between the first and second members, and means for supplying pressure fluid to the piston and cylinder means whereby to provide relative movement between the first and second support members and hence movement of the cutting tool toward and away from the body. A frame 20 is secured by chains 14 to a sewer main 11 in a trench 12. A plate 45 carries an hydraulic motor 50 driving a shaft 28 carrying a rotary cutter 90 for cutting a hole in the sewer; the shaft 28 is rotatably and axially slidable in a bearing 27 carried by the frame 20. Pistons 30 carried by the frame 20 are located in cylinders 32 carried by the plate 45, the cylinders having stops adjacent their ends for limiting movement thereof with respect to the pistons. For effecting movement of the plate 45 pressure fluid is supplied to the cylinders under the control of a distributing valve 41 secured to the plate 45 and operated by a handle 43. The valve 41 is connected in parallel with the motor 50. The pressure supplied to the valve 41 is controlled by an apertured plate 55 and a by-passing relief valve 42. Pressure fluid is supplied to the motor 50 and valve 41 from a tank 61 by a pump 72 driven through a flexible coupling or belt by a petrol engine 69 mounted on the tank 61 and on a tank 60 containing cutter cooling and lubricating liquid. The wheels 66 and handles 64, 68 are provided for transporting the assembly of tanks, engine and pump. The cutter 90 has a hollow cylindrical metal body 91 with a cutting edge 95 of diamonds in a matrix. Liquid from the tank 60 flows by gravity through a pipe 40, carried by the plate 45 and passing through a hole 29 in the frame 20, to the cutter. A valve 57 in the pipe 40 is interconnected with a valve 56 connected between the pressure and return lines of the motor 50 so that when the valve 56 is opened to short-circuit the motor 50 and thus stop it, the valve 57 is closed to stop the flow of coolant to the tool. The electrical circuit of the petrol engine 19 includes switch 83 responsive to the air pressure in a tube 86 extending into the cutter coolant tank 60, so that when the coolant falls below a predetermined level the switch 83 is actuated to stop the engine. |
