Mobile stone crushing plant

Abstract

Abstract A mobile stone crushing machine comprising a chassis on which is mounted a stone crushing unit and endless conveyor, a front end of which is adapted to collect stones from the ground as the machine is advanced over the ground, and from which the stones are continuously discharged into a stone crushing unit, characterized in that the stone crushing unit includes two crushing zones, each of which incorporates at least one crushing roller, so arranged that the stones to be crushed first pass through a nip associated with the roller at the first zone and on discharge from this nip the partially crushed stones and other matter then pass through a nip associated with the roller at the other zone. Preferably, the two crushing zones are arranged one above the other and each incorporates a pair of crushing rollers, one of which is rotatable about a fixed axis and driven and the other of which is supported upon a pair of trailing swing arms. This invention relates to a mobile stone crushing machine intended mainly for agricultural purposes, and which will eliminate the traditional hand collection of large stones and transporting them for either crushing in a static plant or disposal by burying them in pits. The presence of large stones on land used for root crops causes bruising and laceration of the skins, especially potatoes when harvested by mechanical means, not to mention damage to machinery, and the invention has for its object to provide a mobile crushing machine which will enable the stone size in the soil of any agricultural field to be regularised, thereby making for better growing conditions. According to the present invention, a mobile stone crushing machine comprises a chassis on which is mounted a stone crushing unit and an endless conveyor, a front end of which is adapted to collect stones from the ground as the machine is advanced over the ground, and from which the stones are continuously discharged into the stone crushing unit, and wherein the stone crushing unit preferably includes two pairs of crushing rollers, so arranged that the stones to be crushed first pass through the nip of one of the pairs of rollers, and on discharge from this nip, the partially crushed stones and other matter then pass through the nip of the other pair of rollers. Instead of two pairs of rollers being provided, however, it is envisaged that at each crushing zone, a roller could operate in conjunction with a fixed plate. Preferably the conveyor extends upwardly and rearwardly and the first pair of rollers are superimposed above the other pair and the crushed stone therefrom is preferably deposited onto the ground. The machine may be in the form of a trailer or a self-propelled vehicle. The stone crushing unit is preferably enclosed except for its underside in a casing or armoured shroud and side screens, the unit being adjustably suspended on the chassis to enable its distance above ground level to be varied according to operating conditions. The rollers of each pair work in contra-rotation and preferably one roller in each pair is driven, preferably the leading one, and the other and trailing roller is adjustably mounted to vary the gap between the rollers. Preferably, each trailing roller is mounted on a pair of trailing suspension arms for free swinging movement about a horizontal axis, to allow the passage of uncrushable materials, so that the crushing forces are provided by the weight of the rollers. Preferably, spring damping means are also provided for each trailing roller. Preferably, at least one deflector plate is associated with the upper pair of rollers to direct stones discharging from the conveyor into the nip of the rollers. This plate may be kinked and extend downwardly from the shroud to within an inch or so of the surface of the trailing roller. In order to catch stones as they are thrown upwardly by the driven roller after discharge onto it, a second horizontally disposed deflector plate located above the nip and associated with the first one, may be provided. Preferably, the two pairs of rollers are arranged exactly one above the other, and to prevent crushed material emerging from the nip of the first pair passing directly through the nip of the second pair, a third deflector plate is provided, to catch the said material and throw it forwardly onto the driven roller of the second pair. Provision may be made for adjusting the height of the conveyor at its collecting end and/or for a scoop to be attached thereto. In one such arrangement, the conveyor comprises a frame privotally attached at its discharge end to uprights on the chassis, its other end being adjustably supported by means of a linkage under the control of, e.g. a hydraulic ram, to enable it to be inched up and down. The conveyor may be of slatted construction so that extraneous dirt can be released and for this purpose agitators may be incorporated into the conveyor unit for separating clods of earth and smaller stones. Preferably, two endless conveyors are provided side by side, each having side screens, and a plate is provided beneath the upper arm of the upper part of each one.

Inventors

• 👤 William Whytock Hally
• 👤 Thomas Pate, Jr.

Bibliographic Details