SPREADER FOR GRANULAR MATERIAL

Abstract: There is disclosed a spreader device (10) for granular or particulate material to be mounted at the rear of a propelling vehicle having a storage hopper for the material, and in which the device comprises: a support housing (11) having a pair of opposed side walls (13), a spinner assembly (14) mounted on housing (11), a parallelogram type swing arm linkage (15) pivotally mounted on one wall (13) of housing (11) and also pivotally connected to spinner assembly (14) to permit the assembly to be moved between a forward in-board position and a rearwardly projecting position, an upright drive shaft (16) rotatably mounted in assembly (14) and carrying a spinner disc (18), and first and second latch elements (26, 24) provided on one housing wall (13) and one arm (20) of parallelogram linkage (15) and which co-operate in order to latch the assembly in the rearwardly projected position, but which can be forcably disengaged by application of a sufficient forwardly directed force e.g. when the vehicle backs into an obstacle, in order to release the arm (20) of the linkage and thereby allow the linkage to swing on its pivotal mounting (22) and cause the assembly to move towards its forward inboard position.

Description: SPREADER FOR GRANULAR MATERIAL This invention relates to a spreader for granular or particulate material and which is adapted to be mounted on a propelling vehicle having a hopper for storing the material and which is arranged to receive a supply of the material from the hopper and to distribute the material over the ground. The invention has been developed primarily in connection with a spreader to be mounted at the rear end of a "road gritter". in order to distribute granular material in the form of sand, road grit and / or road "salt" onto the road surface when icy conditions prevail or are anticipated . In one known arrangement, the spreader comprises a spinner disc which is carried by a vertical shaft and which is rotated by the shaft while at the same time the material to be distributed is guided to fall under gravity onto the rotating surface of the disc and is then distributed generally radially outwardly of the disc by centrifugal action. The spinner disc assembly is mounted at the rear of the vehicle via parallelogram type linkages each composed of a pair of swinging arms or links arranged on each side of the assembly and from which the spinner disc assembly is suspended. This enables the spinner disc to be moved to a rearwardly projected position from its mounting at the rear of the vehicle so that the material can be distributed onto the road and without risk of the material being directed towards part of the structure of the vehicle. However, when the spreader takes-up its rearwardly projected position, this increases the overall length of the vehicle which can cause problems in maneouvering the vehicle when it is not involved in road gritting operations. It is therefore desirable for the entire spreader assembly to be capable of being moved forwardly to an in-board position in order to reduce the overall length of the vehicle. Therefore, in the known arrangement of spreader, a spring arrangement is provided which is connected to the parallelogram linkages in such a way as to apply a continuous rearward biasing force to the linkages which urge the spinner disc assembly to maintain the rearwardly projected position, but which can yield to allow the assembly to be pushed forward against the spring biasing to take-up a forward in-board position. This is particularly useful in the case when the vehicle is reversed unintentionally against a rearward obstacle, in that the spinner disc assembly can move forwardly against its spring biasing in such a situation and thereby avoid damage to the spreader. The present invention also is concerned with a spreader for granular or particulate material which is intended to be mounted at the rear of a propelling vehicle (having a storage hopper for the material) and via swinging link type supports which permit the spreader to be moved between a rearwardly projected position and a forward position, but which avoids the necessity for any spring biasing to be provided to urge the spreader towards the rearwardly projected position. According to the invention there is provided a spreader device for granular or particulate material and which is intended to be mounted at the rear of a propelling vehicle having a storage hopper for such material, and means for transferring the material from the hopper to the spreader device, and said device comprising: a support housing which is mounted at. or adapted for mounting at the rear of the propelling vehicle, and which comprises a pair of opposed side walls: a spinner assembly mounted on said support housing: a parallelogram type swing arm linkage pivotally mounted on one wall of said support housing and also pivotally connected to the spinner assembly to permit the assembly to be moved between a forward in-board position at least partly located between the two walls of the support housing, and a rearwardly projected material discharge poεit ion : an upright drive shaft rotatably mounted in the assembly and carrying a spinner disc which is rotatable by the shaft in order to discharge material supplied to the disc in a laterally outwardly direction under centrifugal action : and . first and second latch elements provided on said one housing wall and on one arm of said linkage, said latch elements being co-operable in order to latch the assembly in the rearwardly projected material discharge position, but which are disengageable upon application of a sufficient forwardly directed force to the assembly in order to release said one arm of the linkage and thereby allow the linkage to swing on its pivotal mountings on said one wall and cause the assembly to move towards the forward in-board position. Thus, in the event of the vehicle reversing into contact with a rearward obstacle which engages the spreader device when the latter is in its rearwardly projected position, the spinner assembly can disengage the first and second latch elements and thereby allow the assembly to move forwardly and avoid any damage being done to the assembly. Preferably, a spring arrangement is provided biasing means is provided to bias the first and second latch elements into engagement with each other when the assembly is in the rearwardly projected position, but which is able to yield resiliently upon application of the forwardly directed force to the assembly so as to permit disengagement of the first and second latch elements. In a preferred embodiment, a respective parallelogram linkage is mounted pivotallv on each opposed wall of the support housing and engages pivotally on a respective one of the two opposed sides of a spinner housing of the spinner disc assembly. The first latch element may be formed by a projecting peg which is secured to said one arm of the associated parallelogram linkage, and the second latch element may comprise a latch plate having a latching recess in which the peg can be received. The latch plate may be pivotally mounted, and preferably has a slide surface over which the peg can slide during adjustment of the assembly, and this slide surface may have one or more additional latching recesses which determine intermediate latching position(s) corresponding to positions of the assembly intermediate the fully forward or fully rearwardly projected positions. The latch plate may be provided with a biasing means which urges the slide surface of the plate into engagement with the peg. but which allows the plate to pivot against the action of the biasing means, if necessary, as the peg slides along the slide surface and into any one of the latching recesses. The biasing means may comprise a rod made of extensible material e.g. a polymeric retainer rod. which is connected to the latch plate so as to resist pivoting movement of the plate when the peg moves along the slide surface. When the spreader device is mounted at the rear of a vehicle, the material may be conveyed from the hopper to the spinner disc via a conveyor and suitable guide chutes arranged in the support housing and also on the spinner housing, which directs the material towards a central region of the spinner disc, whose rotation then directs the material laterally outwardly under centrifugal action. One embodiment cf spreader device according to the invention will now be described in detail, by way of example only, with reference to the accompanying drawings. in which : Figure 1 is a rear view of a spreader device according to the invention, mounted at the rear end of a road gritter vehicle: Figure 2 is a view from one side, to a reduced scale, taken in the direction of the arrows X in Figure 1; Figure 3 is a longitudinal sectional view, to a reduced scale, taken on the line Y-Y in Figure 1; Figure 4 is a detailed side view of a spinner assembly of the spreader device: and. Figure 5 is a plan view of a housing in which the spinner assembly is mounted. Referring now to Figures 1 to 3 of the drawings, there is shown an embodiment of spreader device according to the invention, which is designated generally by reference 10. and which is intended to distribute laterally granular or particulate material over the ground. The device 10 is intended to be mounted at the rear of a propelling vehicle (not shown) having a storage hopper for granular or particulate material, such as grit or sand and road "salt" of the type used on roads in winter, and the vehicle also including conveyor means for transferring such material from the hopper to the spreader device. The spreader device is particularly suitable to be used in distributing material from road gritt.er vehicles. The spreader device 10 comprises a support housing 11 which is adapted to be mounted at the rear of the propelling vehicle, and Figures 1 to 3 show part- of a rear support structure 12 of a vehicle on which the support housing 11 can be mounted. The housing 11 comprises a pair of opposed side walls 13 which define therebetween a space through which the material to be distributed can be guided bv suitable guide chutes (not shown in detail) after being supplied thereto by a conveyor running from the hopper of the vehicle. A spinner assembly 14 is mounted on the side walls 13 O 92/15755 of the support housing 11 via a pair of parallelogram type swing arm linkages 15 each mounted on a respective one of the side walls 13 and pivotally connected to the spinner assembly 14. The purpose of the parallelogram type linkages is to permit the assembly 14 to be moved between a forward in-board position (not shown) in which it is at least partly located between the two walls 13 of the support housing 11. and a rearwardly projected material discharge position, as shown in Figures 1 to 3. The spinner assembly 14 includes an upright drive shaft 16 which is rotatably mounted in a fixed housing 17 of the spinner assembly (see Figures 4 and 5). and which carries a spinner disc 18 at its lower end which is rotated by shaft 16 under action of motor 19 in order to discharge material supplied to the disc 18 in a laterally outward direction under centrifugal action. Returning now to Figures 1 to 3, each parallelogram type linkage 15 comprises a pair of swing arms 20 and 21 which are pivotally mounted on upper pivots 22 on the respective side wall 13. and at their lower ends are pivotally connected to the housing 17 of the spinner assembly 14 via pivots 23. The nature of a parallelogram type linkage will be such that spinner shaft 16 is maintained at the same substantially vertical attitude throughout movement of the assembly 14 between its rearward and forward positions, and therefore spinner disc 18 will maintain a substantially horizontal attitude. The assembly 14 is shown in Figure 1 to 3 occupying a rearwardly projected material discharge position, but it can be pushed forwardly to an in-board position, upon application of a sufficient forwardly directed force to the assembly. However, a latching arrangement is provided to maintain the assembly 14 in either of its forward and rearward positions, and desirably also in any selected intermediate position. The latching arrangement comprises first and second latch elements, with the one latch element comprising a latch plate 24 pivoted at its upper end on housing wall 13 via pivot 25 and a further latch element comprising a peg 26 provided on arm 20 of linkage 15. Each peg 19 moves through an arc centred on upper pivot 22 of arm 22. and is guided to move in a guide slot 27 formed in the side wall 11. During movement along this guide slot 27. peg 26 can slide along an undulating slide surface 28 of latch plate 24, with surface 28 being provided with latching recesses in which peg 26 can be received in order to latch the linkage 15 to the side wall 11. As shown in Figure 2. peg 26 occupies a latching recess 29 which corresponds with the rearwardly projected position of assembly 14. and a strengthening plate 20 is arranged adjacent to this recess 29. The engagement between peg 26 and the slide surface 28 is such that it can latch the assembly 14 in the forward, the rear or any desired intermediate position, but can be disengaged from latching engagement upon application of a sufficient force to the assembly. This then causes release of arm 20 which allows each linkage 15 to swing on its pivotal mountings 22 and cause the assembly to move to any required new position e.g. to move from the rearward position to the forward in-board position. Therefore, in the event of the vehicle reversing into contact with a rearward obstacle, (with the assembly 14 in the rearward position), the assembly 14 can be displaced forwardly by this engagement in order to disengage the latch elements 24. 26. and thereby allow the assembly to move forwardly and avoid any damage being done to it. A spring arrangement is provided to bias the first and second latch elements (26. 24) into engagement with each other, for any required latched position, but this spring arrangement can yield reεiliently upon application of force to the assembly so as to permit disengagement of the latch elements. In the illustrated embodiment, the biasing means takes the form of a rod 31 made of extensible material e.g. a polymeric retainer rod. which is connected at its upper end to housing wall 13. and at its lower end to one end of its corresponding latch place 24. This allows the latch plate 24 to pivot about its upper pivot 25 in an anti-clockwise direction, as seen in Figure 2. to allow peg 26 to move over slide surface 28. The pivotal movement of the latch plate 24 also takes place under the action of a further peg 32 fixed to the side wall 13. and received by a guide slot 33 in the latch plate 24. If it should be required to disengage the latch elements 24. 26 by other means, handles 34 which are attached to the ends of the latch plates 24 may receive suitable downward pressure which will disengage the pegs 26. and thereby allow easier forward or rearward movement of assembly 14. Therefore, the illustrated embodiment of the invention provides a spinner disc assembly of a spreader device which can be readily displaced between operative and inoperative positions, but can reliably maintain any adjusted position under engagement of the respective latch elements. However, disengagement of the latch elements can readily be achieved, thereby allowing forward or rearward displacement of the spinner disc assembly by manual action or in the event of unintended engagement with a rearward obstacle during reversing of the vehicle. Although not shown in detail, spinner housing 17 may be provided with suitable guide chutes which enable the material to be discharged towards a central region of disc 18.

Claims: CLA I MS 1. A spreader device (10) for granular or particulate material and which is intended to be mounted at the rear of a propelling vehicle having a storage hopper for such material, and means for transferring the material from the hopper to the spreader device, and said device comprising: a support housing (11) which is mounted at. or adapted for mounting at the rear of the propelling vehicle, and which comprises a pair of opposed side walls (13): a spinner assembly (14) mounted on said support housing: a parallelogram type swing arm linkage (15) pivotally mounted on one wall (13) of said support housing (11) and also pivotally connected to the spinner assembly (14) to permit the assembly to be moved between a forward in-board position at least partly located between the two walls of the support housing, and a rearwardly projected material discharge position: an upright drive shaft (16) rotatably mounted in the assembly (14) and carrying a spinner disc (18) which is rotatable by the shaft in order to discharge material supplied to the disc in a laterally outwardly direction under centrifugal action: and. first and second latch elements (26. 24) provided on said one housing wall (13) and on one arm (20) of said linkage (15). said latch elements being co-operable in order to latch the assembly in the rearwardly projected material discharge position, but which are disengageable upon application of a sufficient forwardly directed force to the assembly in order to release said one arm (20) of the linkage and thereby allow the linkage (15) to swing on its pivotal mountings (22) on said one wall and cause the assembly to move towards the forward in-board position. 2. A spreader device according to Claim 1 , including biasing means (31 ) to bias the first and second latch elements (26. 24) into engagement with each other when the assembly (14) is in the rearwardly projected position, but which is able to yield resiliently upon application of the forwardly directed force to the assembly so as to permit disengagement of the first and second latch elements. 3. A spreader device according to Claim 1 or 2. in which a respective parallelogram linkage (15) is pivotally mounted on each opposed wall (13) of the support housing (11) and engages pivotally (23) on a respective one of the two opposed sides of a spinner housing (17) of the spinner disc assembly. 4. A spreader device according to any one of Claims 1 to 3. in which the first latch element is formed by a projecting peg (26) which is secured to said one arm (20) of the associated parallelogram linkage (15) , and the second latch element comprises a latch plate (24) having a latching recess (29) in which the peg can be received. 5. A spreader device according to Claim 4, in which the latch plate (24) is pivotally mounted, and has a slide surface (28) over which the peg (26) can slide during adjustment of the assembly. 6. A spreader device according to Claim 5. in which the slide surface (28) has one or more additional latching recesses (29) which determine intermediate latching positions corresponding to positions of the assembly intermediate the fully forward or fully rearwardly projected positions. 7. A spreader device according to Claim 5. when appendant to Claim 2. in which said biasing means (31) engages the latch plate (24) to urge the slide surface (28) into engagement with the peg (26) but which allows the plate (24) to pivot against the action of the biasing means (31 l . if necessary, as the peg slides along the slide surface and into any one of the latching recesses. B. A spreader device according to any one of Claim 7. in which the biasing means comprises a rod (31) made of extensible material which is connected to the latch plate (24) so as to resist pivoting movement of the plate when the peg (26) slides along the slide surface (28).

Inventors: COTTON WILLIAM, MCGEE TERENCE, COTTON, WILLIAM, MCGEE, TERENCE
Applicants: CONVEYORS YORKSHIRE LIMITED, WEST YORKSHIRE HIGHWAYS ENGINE, CONVEYORS (YORKSHIRE) LIMITED, WEST YORKSHIRE HIGHWAYS ENGINEERING AND TECHNICAL
Application year: 1992
Main classification: E01C19
IPC codes: E01C19