IES970672A2 - A mixing and dispensing apparatus - Google Patents

Abstract

An apparatus for mixing, dispensing and evenly mixing animal foodstuffs using a plurality of spaced apart and radially offset paddles (35, 52) carried on a shaft (30). The shaft (30) being rotatably housed and lying along a longitudinal axis of a container. A paddle comprises a support arm (32) mounted on the shaft (30) wherein the plate (65) is pivotally secured to the support arm (32) is adapted to deflect from an operating position. [GB2329098A]

Description

ai.iE5 ----1 \ 0p6®J " 1 " ,f ' Π ^ ^ Xi!******^ A MIXING AND DISPENSING APPARATUS The present invention relates to a mixing and dispensing apparatus and more particularly to a tractor drawn 5 apparatus for mixing and dispensing feed for animals.

Traditionally, mixing and dispensing apparatus comprises an open topped container having an auger for mixing feed material and for propelling the material to one end of the 10 container where it is dispensed through an aperture in the side wall of the container. The feed material has a tendency to coagulate or "clump" resulting in uneven mixing and higher torque requirements from the auger.

Paddle type mixers attempt to overcome the disadvantages of known auger-based mixers. A paddle type mixer normally comprises a substantially cylindrical container having a driven shaft along the container's longitudinal axis.

Radial arms are provided along the shaft each of which is 20 terminated with a paddle which may be set at an angle for improved mixing. While these arrangements provide adequate mixing for relatively fine grade material, they are unsuitable for dry material, coarse grade material or fibrous material which has to be broken down.

Typically, paddle type mixers and dispensers comprise an — open-topped container, the container having a closeable ^ dispensing outlet adjacent one end of the container and a 8 a [mixing means comprising a plurality of mixing paddles uj y 30^ rotatably mounted within the container and arranged to CC move material in the container towards the dispensing q £ z ^ outlet, and at least one dispensing paddle rotatably 3 Q 5 ί ω Z oo mounted within the container and arranged to discharge 3 3 ϊμ g material in the container through the dispensing outlet. }5 p rhe mixing and dispensing paddles are mounted on a Z. ί p IJ.? · "*.· ··>*«** c g. \ _ 2 _ IE 970672 rotatable shaft mounted in the container. Each mixing paddle comprises a plate fixed at one end of a radially projecting support arm, the mixing paddle plate being inclined at an angle of approximately 40° relative to the 5 axis of rotation of the shaft. The dispensing paddle which also comprises a plate is disposed substantially perpendicularly to the axis of rotation of the shaft.

These arrangements of paddle type mixers and dispensers 10 are not particularly suited for dry or coarse grade material and suffer from a number of distinct disadvantages. Firstly, there is a known problem with material build-up about the paddles, particularly when the load approaches the maximum capacity of the container.

Normally, bridging occurs between a paddle and its support arm. This is a particular problem with dry or coarsely chopped material. Secondly, dry or coarsely chopped material is unevenly discharged through the dispensing outlet. Often a large amount of material becomes jammed 20 in and around the dispensing outlet. Thirdly, when such an apparatus is being loaded or filled, the dispensing paddle presents a straight face to which the loading material will adhere, consequently causing jamming between the wall of the container and the paddle when the material 25 starts to bridge. Finally, the dispensing outlet discharges material at a relatively low discharge height; consequently a conveyor is usually required, adding significantly to the cost of the mixing and dispensing apparatus .

To alleviate the above disadvantages and to provide an improved mixing and dispensing apparatus, co-pending Irish Short-Term Patent Application No. S950571 dated 9th August 1996 provides a mixing and dispensing apparatus 35 for animal foodstuffs and like material comprising an IE 970672 - 3 - open-topped container having a closeable dispensing outlet, and a mixing means comprising a plurality of mixing paddles rotatably mounted within the container and at least one pair of dispensing paddles rotatably mounted 5 within the container, the dispensing paddles being arranged to discharge material in the container through the dispensing outlet, each paddle being fixed to a rotatable shaft mounted along the longitudinal axis of the container and comprising a support arm and a plate 10 angularly disposed at a predetermined angle with respect to the axis of rotation of the shaft, wherein the plates of the dispensing paddles are arranged in oppositely facing pairs to improve the rate of transfer of material through the outlet and the plates of the mixing paddles 15 are disposed to urge material towards the dispensing paddles .

While the above mentioned application overcomes the problem of bridging between the paddles, coarse material 20 tends to build up along the paddle plates and paddle support arms. The angular disposition of the plates with respect to the axis of rotation of the shaft decreases the incidence of jamming when material is being loaded into the container thereby decreasing the machine torque 25 requirements. However, jamming is not eliminated especially when bulky loads are added. Additionally, large bales cannot be digested by the apparatus.

It is an object of the present invention to seek to 30 further decrease the incidence of jamming in mixing and dispensing apparatus and to provide an apparatus capable of digesting large bales.

Accordingly, the present invention provides a mixing and 35 dispensing apparatus for animal foodstuffs and like . 4 . IE 970672 material comprising a open-topped container having a closeable dispensing outlet, and a mixing means comprising a plurality of mixing paddles and at least one pair of dispensing paddles rotatably mounted on a common axis 5 within the container, the dispensing paddles being arranged to discharge material in the container through the dispensing outlet, each paddle being fixed to a rotatable shaft mounted along the longitudinal axis of the container and comprising a support arm and a plate at the 10 end of the arm, wherein the plate is pivotally secured to the support arm and adapted to deflect from an operating position, angularly disposed at a predetermined angle with respect to the axis of rotation of the shaft, to a deflected position substantially perpendicular to the axis 15 of rotation of the shaft, thereby preventing jamming and reducing torque requirements of the apparatus.

The paddle plate is biased towards its operating position by a spring mechanism fixed at one end to the support arm 20 and at the other end to the plate.

The spring mechanism includes a spring tensioning device to ensure the spring is biased to deflect only on encountering a major blockage or obstruction.

Preferably, each paddle comprises a cantilever plate, that is the paddle support arm is connected to the plate at a point disposed from the centre of the plate. The cantilever paddles prevent material build-up thereon as 30 any substantial material build-up is forced off by its own weight. Most preferably, the support arm is connected to one end of the plate.

Advantageously, each paddle support arm is provided with 35 a blade adapted to cut material against fixed blades in 5 - IE 970672 the container.

In a preferred embodiment a plurality of static blades are secured in the container between a side wall and the 5 shaft. One end of each static blade is provided with a sleeve through which the shaft rotates and the other end is fixed to the wall.

Preferably, the static blades are arranged to provide a 10 scissors action with the blades mounted on the support arms.

Conveniently, the static blade or the support arm blade presents a serrated edge. In one arrangement both the 15 static blades and the support arm blades are serrated.

The open-topped container comprises a rounded base for housing the shaft, front and end walls and first and second side walls extending from the rounded base, the 20 dispensing outlet being disposed in one of the side walls in a position corresponding to the dispensing paddles.

Preferably, the dispensing outlet is positioned at or adjacent the interface of the rounded base and said side 25 wall.

The plates of the dispensing paddles are disposed at an operating angle of between 25° and 35° to the axis of rotation of the shaft to provide an even discharge through 30 the dispensing outlet. This arrangement facilitates the use of a dispensing outlet disposed relatively high in the wall of the container. The angled plates provide sufficient lift to the material to carry it to a high dispensing outlet so that further elevation of the 35 material is not always required. 6 _ IE 970672 Jamming of material at the dispensing outlet deflects the plates rearwardly to relieve the jamming and to reduce torque requirements.

The path swept by each paddle plate optionally overlaps the path swept by an adjacent plate. To avoid collision of the plate with a static blade, striking surfaces are provided, on the wall of the container to which the static blades are fixed, to deflect the paddle plate from 10 its operating position sufficiently to clear the static blade.

The dispensing paddles are arranged with overlapping paths to enhance discharge rates through the dispensing outlet. 1 5 The present invention further provides an improved paddle for use with an apparatus for mixing and dispensing animal foodstuffs and like material of the type comprising an open-topped container having a driven shaft along the 20 container's longitudinal axis, the shaft including mixing and dispensing paddles, the paddles each comprising a radial support arm fixed to the shaft at one end and a pivotally mounted plate at the other end, the plate being biased to assume an operating position from which it may 25 be deflected should an obstacle be encountered.

The invention will now be described more particularly with reference to the accompanying drawings which show, by way of example only, one embodiment of mixing and dispensing 30 apparatus according to the invention. In the drawings: Figure 1 is a perspective side view of the mixing and dispensing apparatus from the side, with the container body shown in dotted outline; 35 - 7 - Figure 2 is a perspective view of the apparatus from above; Figure 3 is a perspective view from the rear of 5 the apparatus along the rotating shaft showing the position of the paddles with respect to the shaft; Figure 4 is a phase diagram of the shaft of Figure 3 illustrating the positions of the paddles with respect to 10 one another and the angles subtended therebetween; Figure 5 is a schematic representation of paddle positions with respect to one another, their sweeps and their positions within the container; 1 5 Figure 6a to 6c are perspective views of an intermediate paddle illustrating paddle plate movement, an end paddle and an intermediate paddle such as a dispersing paddle with a rearwardly facing plate; and 20 Figure 7a and 7b are mirror images of a static blade.

Referring to Figures 1 to 3 of the drawings, a mixing and dispensing apparatus comprises an open-topped container 10 25 mounted on a wheeled chassis for towing by a prime mover such as an agricultural tractor (not shown). The container 10 has a substantially rectangular open top defined by a first side wall 13 including a dispensing outlet 15, a second side wall 16, an end wall 17, a front 30 wall 18 and has a rounded base 19 housing a driven shaft 30. The dispensing outlet 15 has a door mounted on the side wall 13 and is closeable under action of a hydraulic ram (not shown). A motor driven drum impeller is provided to assist dispensing of material. The outlet 15 is 35 generally located off-centre along the side wall 13 at the IE 970672 - 8 - top of the arcuate portion of the rounded base 19 to provide an elevated discharge point. A ramp is optionally formed in the side wall 13 from the rounded base 19 to the outlet 15 to improve the dispensing rate of dispensing 5 paddles (described in more detail hereinafter) when the door is open. A chute (not shown) is normally provided for dispensed material but a conveyor may be attached to the outlet 15 for higher discharge.

The shaft 30 has a series of paddles attached thereto, each paddle comprising a plate held to the shaft 30 by a supporting arm 32. The paddles are referred to by function, that is, each paddle is either a mixing paddle or a dispensing paddle. The first paddle 35 is a mixing 15 paddle which is provided with a rearwardly facing plate and is disposed on the shaft 30 adjacent the front wall 18 of the container to urge material from the front wall 18 towards the centre of the open-topped container 10. The second 37 and third 39 paddles are dispensing paddles 20 arranged to urge material from the container 10 towards the dispensing outlet 15. These paddles are provided as an opposing pair, that is, their respective plates are oppositely facing to concentrate material along a path towards the dispensing outlet 15. The second paddle 37 25 has a rearwardly facing plate angled at an operating angle of 30° to the axis of rotation of the shaft and the third paddle 39 has a forwardly facing plate also at an operating angle of 30° to the axis of rotation of the shaft.

The fourth 42, fifth 45 and sixth 47 paddles are provided with forwardly facing plates to urge material towards the dispensing paddles 37,39. The plates of the fourth 42, fifth 45 and sixth 47 paddles are disposed at an operating 35 angle of 50° to the axis of rotation of the shaft.

IE 970672 - 9 - The final paddle 52 again comprises a forwardly facing plate in a cantilever relationship therewith, the plate being disposed at an operating angle of 40° to the axis of rotation of the shaft 30 and is disposed adjacent the rear 5 wall 17 of the container. All of the paddles 35.37.39.42.45.47.52 are held by their respective supporting arms 32 in a cantilever relationship so that material is not allowed to aggregate on the plate or the supporting arm. This arrangement also avoids the 10 possibility of material bridging between the paddle plates and the walls of the container. Static knives 60 are provided between the inside of the second side wall 16 and the rotating shaft 30 and will be described in more detail with reference to Figures 7a and 7b.

Referring now to Figure 4, a phase diagram illustrates the angular relationship between each of the paddles 35.37.39.42.45.47.52 about the shaft 30 viewed from the rear of the apparatus. Taking the first rearwardly facing 20 paddle 35 as the starting point, the second paddle 37 is disposed at an angle of 162° to the first paddle, that is, the shaft 30 must rotate through 162° for the second paddle 37 to assume the position of the first paddle 35. The third paddle 39 is disposed at an angle of 72° from 25 the second paddle 7 (the third paddle 39 must rotate through an angle of 72° to assume the position occupied by the second paddle 37 in Figure 4). Similarly, the fourth paddle 42 is disposed 72° from the third paddle 39, the fifth paddle 45 is disposed 72° from the fourth paddle 42, 30 the sixth paddle 47 is disposed 72° from the fifth paddle 45, and the seventh paddle 52 is disposed 180° from the sixth paddle 45. The regular angular displacements of one paddle from the next are selected to ensure efficient mixing and to prevent bridging of material between the 35 paddles. This arrangement of paddles and static blades is IE 970672 - 10 - particularly efficient at mixing and dispensing coarse feed material especially where long fibrous material is added to the feed.

With reference to Figure 5, the position of each paddle and corresponding blade is shown schematically.

It will be seen that the paddles have discrete sweep areas and are positioned to increase the mixing rate and subsequent discharge rate through the dispensing 10 outlet 15. The static blades 60 are arranged as follows: a first blade is disposed between the sweep of the first 35 and second 37 paddle; a second blade is disposed between the sweep of the third 39 and fourth 42 paddle; a third blade is disposed between the sweep of the fourth 15 42 and fifth 45 paddle; a fourth blade is disposed between the sweep of the fifth 45 and sixth 47 paddles; and a fifth blade is disposed between the sweep of the sixth 47 and seventh 52 paddles. Each static blade 60 is positioned adjacent the swept path of a support arm 32 to 20 provide a surface against which material may be trapped and cut.

Referring to Figures 6a to 6c, the paddles 35,37,39,42,45,47,52 are fixed to the rotating shaft 30 by 25 a support arm 32. The support arm 32 comprises a rigid plate 62 which defines a shaft receiving aperture 64 at one end and is shaped to extend outwardly from the shaft 30. At the other end of the support arm 32, a paddle plate 65 is pivotally attached. The paddle plate 65 is 30 held outwardly from one surface of the support arm 32 at the normal operating angle against a torsion spring 67.

In use, the paddle plate 65 remains in its normal operating position, however, should the plate 65 encounter an obstruction, the plate 65 deflects rearwardly to allow 35 the paddle 35,37,39,42,45,47,52 to continue to rotate IE 970672 - 11 - within the container 10. The amount of deflection depends on the force applied by the torsion spring 67 but is typically between 30° and 50°. The force applied by the spring is adjustable by altering the loading on the spring 5 through an adjuster 70. Deflectors 72,74 are provided to protect the pivot area and spring 67 from adverse exposure to the material being mixed. One of the deflectors 74 acts as a stay to strengthen the support arm 32 and also increases mixing of material in the container 10.

One side of the support arm 32 is profiled as a blade surface and, as shown in the illustrations, is provided with teeth 76 fixed to the leading edge 32a of the support arm 32. The teeth 74 provide a serrated blade surface 15 operable to cut material against the cutting surfaces of the static blades 60 which are shown in detail in Figures 7a and 7b. Each static blade 60 is provided at one end with a sleeve 82, through which the shaft 30 is free to rotate, and a support extending outwardly from the sleeve 20 82. The blade support arm 85 is profiled as a blade surface and is provided with teeth 87 fixed to the edge 85a of the support arm 85 corresponding to the leading edge 32a of the paddle support arm 32. The outermost side of the blade support arm 82 is fixed to the inside surface 25 of one 16 of the walls 13,16 of the open-topped container 10.

The combined effect of the static blades 60 and the blade surfaces provided on the paddle support arms 32 rotating 30 about the shaft 30 allows very coarse and fibrous material to be ingested by the mixing and dispensing apparatus.

The arrangement shown is for a mixing and dispensing apparatus comprising an open-topped container having a 35 longitudinal dimension of 4 metres and each paddle plate IE 970672 - 12 - sweeps a discrete path as the shaft 30 rotates. The plate of the first paddle 35 has a sweep of 550 mm parallel to the axis of the shaft 30. Clearance of 30mm is allowed between the first paddle plate and the front wall 18. The 5 support arms of the dispensing paddles are separated by 1000mm and the paddle plates 37,39 have overlapping swept paths. The remaining mixing paddles 42,45,47,52 are all equally spaced over a distance of 2350mm along the shaft 30 and have swept paths of up to 500mm parallel to the 10 axis of rotation of the shaft 30. The seventh panel is also provided with 30mm clearance from the end wall 17.

For larger containers, where the shaft 30 requires a greater longitudinal dimension, the lengths of the paddle 15 plates and the spaces therebetween can be increased without altering the mixing and dispensing efficiency of the paddles. In any case, for containers having a shaft 30 of up to 5 meters in-the length, the phase diagram, as illustrated in Figure 4, may remain identical.

The lengths of the paddle plates and the clearances therebetween can be increased without significantly altering the mixing and dispensing efficiency of the apparatus .

In an unillustrated embodiment, the path swept by each paddle plate 35,37,39,42,45,47,52 overlaps the path swept by an adjacent plate. To avoid collision of the plate with a static blade 60, striking surfaces are provided on 30 the wall 16 of the container 10 to which the static blades 60 are fixed or to a region of the rounded base 19 of the container adjacent that wall 16. The striking surfaces are arranged to deflect the paddle plate from its operating position sufficiently to clear the static 35 blade 60.

IE 970672 - 13 - In the embodiments described above, the dispensing paddles and the dispensing outlet are disposed forwardly from the centre of the apparatus. It will be understood that by transposing the positions of the paddles along the shaft, 5 the dispensing outlet may also be disposed rearwardly from the centre of apparatus. Additionally, by adjusting the angles of the paddles or transposed paddles, as the case may be, the direction of rotation of the shaft may be reversed to allow the discharge outlet 15 be positioned 10 along the opposite side wall 16.

In Figures 1 to 3 and 6a to 6c, described in detail above, the paddle plates are shown in a position deflected from their normal operating position for 15 clarity.

It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various 20 modifications and alterations are possible within the scope of the invention.

MACLACHLAN & DONALDSON, Applicant's Agents, 47 Merrion Square, DUBLIN 2.