US 3153510 A
Description (OCR text may contain errors)
OCL 20, 1964 s. H. BRNNFORS ETAL 3,153,510
ROCK-TUNNELING APPARATUS Filed Feb. 28, 1961 2 Sheets-Sheet 1 Oct. 20, 1964 s. H. BRNNFoRs ETAL 3,153,510
Roux-TUNNELING APPARATUS 2 Sheets-Sheet 2 Filed Feb. 28, 1961 United States Patent O This invention relates toan apparatus for coating a surface `with a concrete binder,` and more particularly for coating with concrete, the arched roof of a rock tunnel freshly exposed by blasting, as the excavation of such tunnel progresses. The apparatus is mainly characterised in that a concrete projection device is mounted on a platform and has a nozzle whose distance from the platform is adjustable and which is turnable in relation to the platform. In particular, the concrete projection or spraying device includes a rod-like, extensible, nozzle holder which is pivotal about a first axis substantially perpendicular to the platform and also about a second axis which is perpendicular to said first axis, the nozzle being pivotally mounted on the holder about axes parallel to and perpendicular to that of the holder.
The invention is described in greater detail below with reference to the accompanying drawing. FIG. 1 of the drawing is a vertical longitudinal section through a tunnel and a concrete spraying apparatus in operation. FIG. 2 shows the concrete applying apparatus in a side elevation.
The reference numeral 1 denotes the temporary face in the tunnel. The reference numeral 2 denotes the muck after a salvo has just been ired, and by means of which a part L has been blasted. The front part of the tunnel has in the above described manner been provided with a protective arched roof 3, which constitutes a protective covering against a fall and which is for example about 10 to l5 cm. thick. Immediately after the salvo has been iired individual stone blocks which were flung a long way are moved towards the muck, for example by means of a suitable machine, so that a wheeled support 4 for a work platform 5 can be moved to the vicinity of the natural roof formed by the blasting at the length L. The platform 5 is located underneath the protective covering 3. A holder 7 for a concrete supply nozzle 8 is swingably mounted in a horizontal plane on a post 6 on the platform. The nozzle extends substantially radially in relation to the holder 7, which is preferably telescopically extendible, so that the nozzle can be swung in the vertical plane. These movements are controlled by a worker on the platform or from the vehicle 4 or the like. The spray nozzle may be of a type known per se. The dry components of the mixture are supplied through a pipe 9 and water is supplied at the nozzle.
The platform is carried by an arm it) swingably mounted on the support 4 and a parallelogram linkage l1 similarly mounted so that the platform can, by a hydraulic cylinder l2, be moved upwardly and parallel to itself.
The platform, concrete spray nozzle and the parts which support the latter are shown in a larger scale in FIG. 2. The post 6 consists of a lower part 20 xed to the platform and a part 2x1 mounted on the part Z0 and rotatable about a vertical axis. In the latter there is a hydraulic cylinder for moving a piston rod 22 vertically; on the upper end of the piston rod 22 the long holder 7 is rotatably mounted about a horizontal axis 23 to swing in a vertical plane. A fitting 24 is xed to the rear end ofthe holder 7, and a rod 26 is pivotally attached to the latter tting and the upper part 21 of the post. The holder 7 consists of an outer part 27 and an inner part 28 longitudinally movable in the outer part; the
3,153,510 Patented 0ct. 20, 1964 ICC spray nozzle 8 is mounted at the front end of the inner part 28. A hydraulic cylinder 29 having a piston rod 3i) is mounted between the parts 27, 28 and is operative to move telescopically the inner part 28 of the holder forwardly and rearwardly in the part 27.
The nozzle is mounted in a bracket 31, which is by means of a pin 32 pivotally connected to a rod 33. The rod 33 is rotatably mounted in a head 34 on the holder part 28 so that the arm 33 and nozzle are swingable about the longitudinal axis of the holder 27, 28. The swinging can be effected by means of hydraulic turning device, known per se. mounted in the head 34. A hydraulic cylinder 37 is swingable about a pin 36 on an arm 35 which projects radially from the arm 33, and the piston rod 38 is pivotally connected to the bracket below the latters swinging axis 32 on the rod 33. The pipes by means of which the pressure medium is supplied to and conducted away from the hydraulically operating devices in the head 34 and to the cylinder 37 are designated by 40 and 41. These pipes are connected by pipes 42 to a pump driven by an electric motor and housed in a casing 43 mounted on the platform 5. Such hydraulically operated devices and pressure pumps are so well known that they do not require any further description. The same applies to the control of the hydraulic devices. The latter can be set in operation by known means by a person standing on the platform by means of hand levers 44.
FIG. 2 shows also the pipe 9 through which the solid dry components of the cement mixture are supplied to the nozzle. They are forced through the pipes by compressed air. 45 denotes a pipe for water which is supplied to the nozzle S at the same time as the dry components and which is mixed with the latter immediately before they are sprayed out through the nozzle. This is necessary with quick setting concrete mixtures and is known per se. Such devices are called cement-gun pneumatic placing machines.
The nozzle can, by means of the apparatus described, be moved to and fro along the arched roof in the tunnel, and can be directed to the side or upwardly and in addition forwardly or rearwardly so that the jet of cement mixture emerging from the nozzle can be directed towards every point on the arched roof in the tunnel and in between the wedged stones in the roof so that the latter are rapidly bonded to each other to prevent them falling down. The part of the natural roof along the length L spaced from the muck is now coated by the spraying apparatus with a thin film of preferably quick setting concrete, and the whole surface should be covered as rapidly as practicable. The supplementary coating with concrete is then effected as described above. The latter can be completed within for example three hours so that the apparatus can be removed and the removal of the muck started. Since the protective roof is thin in relation to completed load carrying concrete lining, which in the methods hitherto used have covered the roof L, the lining presents less obstacle to drilling at the edges of the face 1, so that the drill holes may make a smaller angle with the longitudinal axis of the tunnel. The saw tooth longitudinal section which the wall of the tunnel normally has may now be less marked, and consequently material for completion lling is saved in this respect also.
What we claim is:
1. An apparatus for applying a concrete coating to a surface, said apparatus comprising a movable platform and a concrete spraying device which is mounted on said platform, said spraying device comprising a rod-like extensible holder which is pivotal about a first axis substantially perpendicular to said platform and about a second axis perpendicular to said iirst axis, a spray nozzle pivotally mounted at the free end of said holder about axes o o parallel to that of the holder and perpendicular to that of the holder, and fluid pressure-driven means, adjustable from said platform, for adjusting said nozzle around said axes.
2. The apparatus defined in claim 1, in which the platform is disposed on a support which comprises a Wheeled support member 4, a parallelogram linkage 10, 11, hingedly secured to platform 5 and to wheeled support member 4, and hydraulic means 12 for displacing the parallelogram linkage in a desired direction.
3. The apparatus dened in claim 1, in which the rodlike extensible holder comprises an elongated outer holder part 27 and a telescoping inner holder part 28, and in which a hydraulic piston means 29, 30 is operatively attached to parts 27 and 28 for telescopically moving part 27 within part 28.
4. The apparatus deiined in claim 1, in Which spray nozzle 8 is so mounted that in its normal position it is directed substantially perpendicularly to the longitudinal axis of holder 27, 28.
5. The apparatus defined in claim l, in which spray nozzle 8 is supported by a bracket 31 rockable about an axis 32 perpendicular to, and supported by an arm 33 which is parallel to, the holder 27, 28, said spray nozzle being rotatably mounted on the end of said holder, said K arm 33 having a lateral projection 35 on which is pivotally mounted a hydraulic cylinder 37, the piston rod 38 of which cylinder is pivotally connected tothe bracket 31.
References Cited inthe le of this patent UNITED STATES PATENTS 1,147,546 Rees July 20, 1915 1,583,772 BlaW May 11, 1926 1,835,132 Anania Dec. 8, 1931 2,176,891 Crom Oct. 24, 1939 2,297,099 Crom Sept. 29, 1942 2,429,045 Bellows Oct. 14, 1947 2,750,155 Nixon June 12, 1956 2,895,299 Washabaugh July 21, 1959 f 2,998,861 Hotchkiss Sept. 5, 1961 3,016,201 Brogden Jan. 9, 1962 3,043,395 Volkel July 10, 1962 OTHER REFERENCES Cement Gun Co., Gunite Contractors, Bulletin 2200, Allentown, Pa, 1942, pp. 54 and 55.
Gunite, pages 1 and 15, by Pressure Concrete Co., Newark, New Jersey, 1947.