IE44584B1 - Improvements in or relating to stone spreading trailers - Google Patents

Description

The present invention relates to improvements in stone spreading trailers and conveyors therefor.

Until now, stone spreading trailers have been provided with short conveyor .' booms only, which limits the distance from the trailer to which stones can be spread :5 and the height from which they can be spread.

• ·.·· It is an object of the present invention to provide a conveyor for a stone spreading trailer which overcomes these limitations. _ y According to the invention, a stone spreading trailer comprises a chassis on which is mounted a hopper having an outlet in a lower region thereof, a conveyor ; 10 boom which is pivotally secured at or adjacent one end thereof by means of a first pivot to the chassis at a position underneath said hopper outlet and extending transversely of the chassis and substantially at right angles to the longitudinal axis of the chassis, wherein the boom comprises a first lower section and a second upper section which are articulated together by means of a second pivot, a first pair of hydraulically operated rams connected between said first lower section of the boom and the chassis and operable to swing the boom as a whole in a vertical plane about said first pivot, and a second pair of hydraulically operated rams connected between said first lower section and said second upper section of the boom and operable to swing said second upper section about said second pivot in a vertical -/ plane relative to said first lower section through approximately a right angle between a position in which the two sections are co-linear and extend transversely of the trailer and a position in which the second section is substantially vertical . and positioned alongside the hopper. Suitably the boom as a whole when fully extended is swirigabld about said first pivot through an angle of at least 30° but preferably 40° to the horizontal. The conveyor boom carries a conveyor belt extending between two drums rotatably mounted at either end of the boom. The door in the hopper is preferably openable and closable by means of a hydraulic ram. The various hydraulic rams may be powered by a pump on the tractor via control valves or ϊ by.:a separate pump powered by the power take-off shaft of the tractor. - 2 44584 A counterweight is mounted on the chassis of the trailer on the opposite side to that of the boom to counteract the weight of the boom when it is unfolded and extends transversely from the trailer to its fullest extent.

Advantageously, the drive means for the conveyor belt comprises a hydraulic 5 motor which drives the belt via a speed reduction gear. The hydraulic motor is mounted directly on to the casing of the reduction gear.

The invention will now be more particularly described with reference to the accompanying drawings wherein: Figure 1 is a front view of the trailer with the boom of the conveyor in the 10 folded position for transportation; Figure 2 is a similar view to that of Figure 1 with the boom of the conveyor fully extended for operation; Figure 3 is a similar view to that of Figure 1 with the boom of the conveyor raised to its maximum height; and Figure 4 is a diagrammatic drawing of the hydraulic circuits used in the trailer of Figures 1 to 3.

Referring to Figures 1 to 3 of the drawings, a trailer 1 adapted to be towed by a tractor (not shown) has a hopper 2 mounted on the chassis 3 of the trailer which is provided with two wheels 4, one on either side of the chassis, for transportation. A conveyor 5 has a boom comprising a lower short section 6 and a longer upper section 7 and the two sections are articulated at a pivot 8 so as to be able to move relative to one another in the same vertical plane. The lower end of the short section 6 is attached to the chassis at a pivot 9 and is able to swing in a vertical plane transversely of the trailer. The pivot 9 is located on the chassis of the trailer in such a position that the lower end of the conveyor is directly underneath an opening 10 in the bottom of the hopper through which stones stored in the hopper can fall on to the belt 11 of the conveyor. The opening 10 in the hopper may be completely closed or openable to a variable extent by - 3 4458* means of a sliding door 12 engaged in grooves secured in the hopper and operated by means of a hydraulic ram 13, The relative angular position of the short section 6 and the longer section 7 of the boom of the conveyor may be altered by means of two hydraulic rams 14 the cylinders of which are pivotally mounted at the upper end of and at the side of the short section 6 of the boom and the pistons of which are pivotally mounted at the lower end of the longer section 7.

The height of the boom of the conveyor is adjusted by means of two hydraulic rams 15 located on either side of the short section 6 of the boom at its upper end.

The cylinders of the rams 15 are pivotally'secured to one side of the chassis of the trailer and the pistons are pivotally secured to the top of the upper end of the short section 6.

A conveyor belt 11 extends aTong the boom of the conveyor and rotates around a drum 17 rotatablymounted at the upper end of the longer section 7 of the boom and around another drum 18 rotatably mounted at the lower end of the short section 6. The conveyor:belt has cleats (not shown) attached to its upper surface which may engage in stones lying on the belt, The conveyor belt 11 is moved by the drum 18 which is powered by means of a hydraulic motor 19 via a reduction gear 20. The motor output shaft is journalled directly on to the input shaft of the reduction gear and the motor is secured by bolts to the casing of the reduction gear. This arrangement is effected by boring a blind axial hole in the input shaft of the reduction gear and inserting the output shaft of the motor therein, the two shafts engaging by means of a key. This arrangement simplifies the mounting of the motor on the reduction gear and eliminates the necessity of using a belt drive between the motor and the reduction gear and consequent alignment required.

A small hopper 21 is mounted at the upper end of the longer section 7 of the boom and receives stones discharged by the belt as it rotates round the drum 17. :- 4 <468 4 This hopper discharges the stones on to the required location.

As shown in Figure 4 the pipelines carrying hydraulic fluid to the hydraulic rams are all led to one location 22 at the front end of the chassis of the trailer and three control valves 25 are mounted thereon. The control valves are con5 nected to a hydraulic pump on the tractor by means of flexible hydraulic pipes. Alternatively, a separate power take-off driven pump may be mounted on the tractor or on the trailer and connected to the control valves by hydraulic pipes.

The trailer operates in the following manner. The trailer is towed to the location where it is to be used with the boom of the conveyor in its folded posi10 tion as shown in Figure 1. The two sections of the boom of the conveyor are then aligned by operation of the hydraulic rams 14 the longer section 7 pivoting about the pivot 8 until the end faces 23, 24 of the two sections 6, 7 are in abutment as shown in Figure 2. The height of the conveyor may be adjusted by operation of the hydraulic rams 15, and Figure 3 shows the conveyor raised to its maximum height, the boom elevated to an angle of 40° to the horizontal. The conveyor is moved by means of the hydraulic motor at a suitable speed and the door at the bottom of the hopper opened a suitable distance so that stones stored in the hopper fall on to the conveyor belt and are carried to the hopper 21 at the end of the conveyor boom and are discharged therefrom. Stones may be loaded into the hopper from another vehicle (not shown). The trailer is towed by means of a tractor at a suitable speed so that stones are distributed along a pipe (for example) located in a trench in the ground as the trailer moves. Cleats secured to the conveyor belt engage in stones lying on the belt and assist in raising the stones especially when the conveyor is raised at a large angle.

A counterweight 16 is mounted on the chassis on the side opposite that of the boom 5.

Claims (7)

1. A stone spreading trailer comprising a chassis on which is mounted a hopper having an outlet in a' lower region thereof, a.conveyor boom which is pivotally secured at or adjacent one end thereof by means of a first pivot to the chassis at a position underneath said hopper outlet and extending transversely of the chassis and substantially at right angles to the longitudinal axis of the chassis, wherein the boom comprises a first lower section and a second upper section which are articulated together by means of a second pivot, a first pair of hydraulically operated rams connected between said first lower section of the boom and the chassis and operable to swing the boom as a whole in a vertical plane about said first pivot, and a second pair of hydraulically operated rams connected between said first lower section and said second upper section of the boom and operable to swing.said second upper section about said second pivot in a vertical plane relative to said first lower section through approximately a right angle between a position in which the two sections are colinear and extend transversely of the trailer and a position in-which the second section is substantially vertical and positioned alongside the hopper.

2. A stone spreading trailer as claimed in Claim 1, wherein the boom as a whole is swingable through an angle of at least 30° to the horizontal.

3. A stone spreading trailer as claimed in Claim 1, wherein the boom as a whole is swingable through an angle of at least 40° to the horizontal.

4. A stone spreading trailer as claimed in any one of the preceding claims, wherein the boom carries a conveyor belt extending between two drums rotatably mounted at either.end of the boom. . ‘

5. A stone spreading trailer as claimed.in Claim 4, wherein the drum nearest the chassis is driven by means of a hydraulic motor through a reduction gear, the motor output shaft being journalled directly onto the input shaft-of the reduction gear.

6. A stone spreading trailer as claimed in any of the preceding claims, -6 4 wherein a counterweight is attached to the chassis on the opposite side to that of the boom.

7. A stone spreading trailer substantially as hereinbefore described with reference to Figures 1 to 3 of the drawings.