Portable Crushing Plant

This invention relates to a stone crushing plant of the type that is portable or transported to the site to provide on the spot crushing of stones.

The advantages of portable stone crushing plants are well recognized and put to contribution. The plants of the above type that have been produced and used so far include the basic components, crushing and screening units and conveyors, mounted in mixed combination on a single truck. There results rather complex and low capacity plants due to the small area available on a single truck.

It is a general object of the present invention to provide a portable crushing plant that is mounted on a plurality of trucks to provide a larger size and more productive plant.

It is another object of the present invention to provide a portable crushing plant of the above type that is mounted on a plurality of trucks to allow a simpler construction and operation.

It is a further object of the present invention to provide a portable crushing plant of the above type that includes a control cabin that is centrally and conveniently located to allow control by a single controller.

It is still another object of the present invention to provide a portable crushing plant in which major components are collapsible to a stowage position for transportation.

The above and other objects and advantages of the present invention will be better understood with reference to the following detailed description of a preferred embodiment thereof which is illustrated, by way of example, in the accompanying drawings; in which:

FIG. 1 is a top plan view of a portable crushing plant according to the present invention;

FIG. 2 is a side elevation view of the portable crushing plant of FIG. 1;

FIGS. 3 and 4 are side elevation views of a main truck carrying conveyors in extended and collapsed positions respectively;

FIG. 5 is an end view of the main truck as seen from the left in FIG. 3;

FIG. 6 is an end view of the main truck as seen from the left in FIG. 4;

FIGS. 7 and 8 are side views of a pivotal joint between cooperating conveyor sections and shown in operative and collapsed positions respectively;

FIGS. 9 and 10 are side and top views respectively of a pivotal joint between a laterally collapsible conveyor and the body of the main truck;

FIGS. 11 and 12 are side elevation views of a screen unit in operatively elevated position and downwardly collapsed positions respectively on the carrying truck;

FIGS. 13 and 14 are end views of a screen unit and truck as seen from the right in FIGS. 11 and 12 respectively; and

FIG. 15 is an end view of the main truck and conveyors thereon as seen from the right in FIG. 3.

The illustrated portable crushing plant comprises a main truck 10 particularly provided to carry controls for the overall plant and conveyors for the crushed stones. The portable crushing plant also includes a pair of auxiliary trucks 11 and 12 carrying a pair of conventional crushing units 13 and 14 respectively. These crushing units are positioned at one end of the main truck and are provided with endless conveyors 15 and 16 respectively to convey the crushed stones toward the conveyors on the main truck.

The portable crushing plant also includes another pair of auxiliary trucks 17 and 18 positioned at the other end of the main truck 10 and carrying a pair of stone screening units 19 and 20 respectively.

The main truck 10 carries an elongated box 21 to house controls and drive components for the conveyors, the crushing units 13, 14 and the screening units 19, 20. The box 21 also houses dust collecting components. Main truck 10 forms a conveyor carrying unit and its box 21 has side walls, a top wall and end walls. The trucks 10, 11, 12, 17, and 18 are preferably truck trailers of any appropriate construction. The conveyors mounted on the main truck 10 include a pair of lateral conveyors 22, 23 and a pair of intermediate belt conveyors 24 and 25 each extending lengthwise longitudinally of the main truck 10. Each of these conveyors is pivotable in the fore and aft direction between its operatively inclined position, as shown in FIG. 2, and its collapsed transport position, as shown in FIG. 4. This pivoting of the conveyors is done through hydraulic or pneumatic cylinders projecting from the box 21. The lateral conveyors 22, 23 extend from under the outer end of the conveyors 15, 16 to a higher position to discharge crushed stone materials onto the screening units 19 and 20 respectively. The intermediate conveyor 24 has opposite end portions 26 and 27 projecting at the opposite ends of the main truck and hinged to a corresponding intermediate portion 28 to be folded back over the latter into transport position as shown by the arrows 29, 30 in FIG. 3. Intermediate portion 28 is carried by and extends over the top wall of box 21. The hinges 24a and 24b between the conveyor portions 26, 27 and 28 are shown in FIGS. 7 and 8 and include brackets 31 fixedly secured at the adjoining ends of the conveyor portions and pivoted one to another by a transverse axis at 32. Flexible tubes 33 interconnect the adjoining ends of the tubular members 34 extending longitudinally of the conveyor 24 to provide a fluid channel running from end to end thereof to transmit dust cleaning vacuum along this conveyor. The lateral conveyors 22, 23 operatively project laterally on the opposite sides of the main truck 10 and are pivoted to the box 21 by hinges 35 to be placed in an operative position, as shown in FIG. 5 or in a transport position, as shown in FIG. 6. In the latter position, the conveyors 22, 23 hang flat against the opposite sides of the box 21 to reduce the effective width of the main truck 10 within legal road width limits. The hinge 35 includes a stud 36 slidable endwise through the corresponding side of the box 21 and pivotally attached at its outer end by an horizontal pin 37 to one side of the corresponding lateral conveyor 22 or 23. A control cabin 38 is fixed to the outer end of a mast 39 that is pivoted at its inner end to the box 21 about a transverse axis. An hydraulic cylinder 40 is connected to the mast 39 to pivot the latter and the control cabin between an elevated operative position, as shown in FIGS. 2 and 3, and a lowered transport position, as shown in FIG. 4.

Each of the screening units 19, 20 includes a housing 41 extending longitudinally of the corresponding auxiliary truck and pivoted relative to the latter between an elevated operative position, as shown in FIG. 11, and a lowered transportation position, as shown in FIG. 12. The housing 41 includes a series of superposed screens 42 of downwardly reducing mesh sizes. An inlet chute 43 is pivotally connected at 44 to the housing 41 to pivot between an operative inlet position and a transportation position. In the operative inlet position, as shown in FIG. 11, the inlet chute 43 rests onto the upper edges of the opposite sides of the housing 41 and overlies the upper end of the screens 42. In the inoperative transport position as shown in FIG. 12, the inlet chute is pivotally lowered at the rear of the housing 41. Transverse conveyors 45, 46, 47 are provided in conventional fashion at the lower end of the screens 42 to collect the stones that do not pass through the screens but rather roll down on them. The transverse conveyors 45, 46, discharge onto the intermediate conveyor 24 that feeds the crushing unit 14 with the crushed stones that are still too big. A conveyor 48 extends longitudinally under the screens 42 of each screening unit 19, 20 to pick up the crushed stones passing through the screens and feed them onto another transverse conveyor 49 and 49a respectively, one for each unit 19, 20. Conveyor 49 discharges onto the conveyor 25 from the screening unit 19 and conveyor 49a discharges outwardly to be used as such. The transverse conveyor 47 of each screening unit 19, 20 also discharges laterally off to provide crushed stone material of somewhat larger size compared to the crushed stone material coming off the transverse conveyor 49a of the screening unit 20. As shown in FIGS. 11, 12 and 13 for the screening unit 19, each screening unit 19, 20 includes a gangway along one side and made of a board 50 and rail 51 that are pivoted to the housing 41 and to each other to be laterally collapsible as shown in FIGS. 12 and 14.

As can be understood quite clearly from the arrows in FIG. 1, the uncrushed stones are dropped in the first-stage crusher 13 from where it leaves at the bottom onto the conveyor 15 as crushed stone elements of varying sizes. Those elements are fed by the conveyor 15 onto the conveyor 22 and by the latter onto the screens 42 of screening unit 19. The smallest crushed stone elements fall right through all the superposed screens 42 onto the underlying conveyor 48 that discharges onto the transverse conveyor 49. The latter in turn discharges those smallest elements onto the conveyor 25 and the latter onto conveyor 23, thus bypassing the second crushing stage provided by the crusher 14. Crushed stone elements of somewhat larger mesh size fall on the conveyor 47 of each unit 19, 20 to be outwardly discharged and be used as such. The largest crushed stone elements drop from the screens 42 of the screening units 19 and 20 on the corresponding transverse conveyors 45, 46 that discharge onto the conveyor 24 to be fed into the crusher 14 for a second stage of crushing. That crusher 14 discharges the resulting crushed stone elements onto the conveyor 16 to transport the same by the conveyor 23 to the screening unit 20 where they are screened again as in the screening unit 19.

A bag filter unit 52 of known construction is operatively connected by flexible tubes 54 to the portable crushing plant and in particular to the tubes 34 and flexible branch tubes 53 to suck the dust and produce better environmental conditions around the plant.