IE980751A1 - 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. <Figure 1>.

Description

A MIXING AND DISPENSING APPARATUS present invention relates to an apparatus and more particularly to a tractor drawn mixing and dispensing apparatus 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 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 for 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 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.

'°EN fO PUBLIC MSPEOWiM ,^w^ypically, paddle type mixers and dispensers comprise an (\;Qpen-topped container, the container having a closeable ^dispensing outlet adjacent one end of the container and a 3'fixing means comprising a plurality of mixing paddles Rotatably mounted within the container and arranged to ·. move material in the container towards the dispensing outlet, and at least one dispensing paddle rotatably -Amounted within the container and arranged to discharge ^material in the container through the dispensing outlet. - 2 The mixing and dispensing paddles are mounted on a 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 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 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 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 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. S960571 dated 9th August 1996 provides a mixing and dispensing apparatus for - 3 animal foodstuffs and like material comprising an 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 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 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 are disposed to urge material towards the dispensing paddles.

While the above mentioned application overcomes the problem of bridging between the paddles, coarse material 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 requirements. However, jamming is not eliminated especially when bulky loads are added. Additionally, large bales cannot be digested by the apparatus without being pre-cut by a shear grab or similar type machine.

It is an object of the present invention to seek to further decrease the incidence of jamming in mixing and dispensing apparatus and to provide an apparatus capable of digesting large round and square bales. - 4 Accordingly, there is provided an apparatus for mixing and dispensing animal foodstuffs comprising a controllable dispensing outlet, a mixing means for mixing material in the container provided by a plurality of paddles rotatably mounted within the container, at least one of the said paddles being moveable between an operating and a deflected position.

Ideally, a shaft is mounted along a longitudinal axis of 10 the container.

Preferably, the paddle is provided by a support arm and a plate at the end of the arm.

In one arrangement the plate is pivotally secured to the support arm and adapted to deflect from an operating position.

Preferably, the plate is angularly disposed at a predetermined angle with respect to the axis of rotation of the shaft.

In a preferred embodiment the paddle is biased towards its operating position by a spring mechanism.

Preferably, the spring mechanism is fixed at one end to the support arm and at the other end to a plate.

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

In one embodiment, the spring mechanism includes a four leaf combination. - 5 Preferably, each paddle includes a cantilever plate.

In one arrangement, the cantilever plate is connected to a support arm at a point displaced from the centre of the plate.

In another arrangement, the cantilever plate 10 is connected to a support arm at an end of the plate.

Preferably, a support arm is provided with a blade adapted to cut material against fixed arms mounted within the container.

Preferably, a plurality of static arms are secured in the container between a side wall and the shaft.

In one form of the invention, an end of a static arm is fixed to a side wall of the container and above a rotating shaft.

Preferably, the or each support arm is provided with a blade adapted to cut material in the container.

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

In a preferred embodiment, the static arm includes an orthonganal cutting edge.

Preferably, the static blades are arranged to provide a scissors action with the blades mounted on the support arms . - 6 Preferably, the support arm incorporates a serrated edge.

Preferably, the blade has a serrated edge.

In a preferred arrangement the container is open at a top end thereof and comprises a rounded base for housing the shaft, front and end walls carried on the base and first and second side walls extending upwardly from the rounded base, and having a dispensing outlet in one of the side walls .

Preferably, the dispensing outlet is substantially adjacent the rounded base.

Ideally, the paddle is disposed at an operating angle of between 20° and 80° to the axis of rotation of a shaft mounted in a container to provide an even discharge through the dispensing outlet.

In one embodiment the path swept by a paddle overlaps the path swept by an adjacent paddle.

According to another aspect of the invention there is provided a paddle for use with an apparatus for mixing and dispensing animal foodstuffs and like material comprising an open-topped container having a driven shaft in the container rotating along the container's longitudinal axis, the shaft including a plurality of paddles, each paddle comprising a radial support arm mounted on the shaft at one end and having a pivotally mounted plate at the other end, the plate being biased toward an operating position and being deflectable on encountering an obstacle.

Preferably, a dispenser provided by a dispensing paddle.

Preferably, the dispensing paddle is rotatably mounted within the container.

Conveniently, the container houses a rotatable shaft, a mixing means provided by a plurality of paddles carried on the shaft for mixing material in the container, the paddles being spaced apart and radially offset about a longitudinal axis of the shaft.

Preferably, at least one paddle is movable between an operating and a deflected position.

Conveniently, adjacent paddles are radially offset by greater than 45°.

Preferably, adjacent paddles are offset by between 65° and 80°.

Additionally, a paddle adjacent an end of the container is offset from an adjacent paddle by greater than 150°.

Conveniently, the end paddle is offset from the adjacent paddle by between 175° and 180°.

According to a further aspect of the present invention there is provided a mixing and dispensing apparatus for animal foodstuffs and like material comprising a open-topped container having a closeable dispensing outlet, and a mixing means comprising a plurality of mixing paddles, 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 end of the arm, wherein the plate is pivotally secured to the support arm and adapted to deflect from an operating position, - 8 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 of rotation of the shaft, thereby preventing jamming and reducing torque requirements of the apparatus.

The paddle plate is biased towards the operating position by a spring mechanism fixed at one end to the support arm 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 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 a blade adapted to cut material against fixed arms in the container.

In a preferred embodiment a plurality of static arms are secured in the container between a side wall and the shaft. The centre of each static arm is provided with a sleeve through which the shaft rotates and the other end is fixed to the wall.

Preferably, the static arms are arranged to provide a scissors action with the blades mounted on the support arms. - 9 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 dispensing outlet being disposed in one of the side walls in a position corresponding to the dispensing paddles.

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 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.

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 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 be deflected should an obstacle be encountered.

For the purposes of this specification the term static arm is taken to include arms having blades attached, formed with a cutting edge and plain arms. Similarly, the term - 10 paddle is intended to include cutting paddles and noncutting paddles formed to provide a cutting action against the static arms.

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 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; Figure 2 is a perspective view of the apparatus from above; Figure 3 is a perspective view from the rear of 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 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; 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 Figure 7a and 7b are mirror images of a static blade. - 11 Figure 8 is an internal perspective view of the apparatus showing the position of the paddles with respect to the shaft.

Figure 9 is a perspective view showing the supporting arm of the paddle.

Figure 10 is a perspective view of the supporting arm incorporating the paddle and hinge device. 0 Figure 11 is a phase diagram showing the angles between the arms .

Figure 12 is a plan view of the apparatus showing the paddle layout.

Figure 13 is a side view of the leaf spring arrangement.

Referring to Figures 1 to 3 of the drawings, a mixing and dispensing apparatus comprises an open-topped container 10 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 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 generally located off-centre along the side wall 13 at the 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 - 12 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 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 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 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 angle of 50° to the axis of rotation of the shaft. 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 - 13 wall 17 of the container. All of the paddles ,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 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 ,37,39,42,45,47,52 about the shaft 30 viewed from the rear of the apparatus. Taking the first rearwardly facing 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 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, 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 paddles. This arrangement of paddles and static blades is particularly efficient at mixing and dispensing coarse feed material especially where long fibrous material is added to the feed. - 14 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 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 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 provide a surface against which material may be trapped and cut.

Referring to Figures 6a to 6c, the paddles ,37,39,42,45,47,52 are fixed to the rotating shaft 30 by 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 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 the paddle 35,37,39,42,45,47,52 to continue to rotate 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 - 15 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 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 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 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 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 longitudinal dimension of 4 metres and each paddle plate 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 - 16 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 and have swept paths of up to 500mm parallel to the 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 10 greater longitudinal dimension, the lengths of the paddle 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 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 blade 60. 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, the dispensing outlet may also be disposed - 17 '*= »80751 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 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 clarity. 0 Referring now to Figures 8 to 12 there is illustrated another embodiment at the apparatus indicated generally by the number 180. Parts similar to those described with reference to Figures 1 to 7 are identified by the same reference numbers generally.

In this embodiment a series of paddles 111-122 are again carried on the shaft 30. Paddles 111, 112, 113, 115, 117, 119 and 121 are rearward facing and have plates 65 connected to the shaft 30 by supporting arms 172 to produce an even mix throughout the length at the container. As previously described the arms and paddles are cantilevered to prevent blockages. The paddle 122 faces forward to prevent accumulation of material against the rear wall.

Referring now in particular to Figure 11 , a phase diagram illustrates the angular relationship between each of the paddles 111, 112, 113, 115, 117, 119, 121, 122 and the arms 114, 116, 118, 120 about the shaft 181 viewed from the rear of the apparatus. Taking the first rearwardly facing paddle 111 as the starting point, the second paddle 112 is disposed at an angle of 180° to the first paddle, that is, the shaft 181 must rotate through 180° for the second paddle 112 to assume the position of the first - 18 paddle 111. The third paddle 113 is disposed at an angle of 80° from the second paddle 112 (the third paddle 113 must rotate through an angle of 80° to assume the position occupied by the second paddle 112 in Figure 11). The fourth arm 114 is disposed 180° from the third paddle 113, the fifth paddle 115 is disposed 100° from the fourth arm 114, the sixth arm 116 is disposed 180° from the fifth paddle 115, and the seventh paddle 117 is disposed 100° from the sixth arm. The eighth arm 118 is disposed 180° from the seventh paddle 117 and the ninth paddle 119 is disposed 100° from the eighth arm 118. The tenth arm 120 is disposed 180° from the ninth paddle 119, and the eleventh paddle 121 is disposed 120° from the tenth arm 120. The twelfth paddle 122 is disposed 180° from the eleventh paddle 121. The regular angular displacements of one paddle from the next are selected to ensure efficient mixing and to prevent bridging of material between the paddles. This arrangement of paddles and static arms is particularly efficient at mixing and dispensing coarse feed material especially where long fibrous material is added to the feed.

Referring now to Figure 12, the position of each paddle and arm and static 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 outlet 185. The static arms 90 are arranged as follows: a first arm is disposed adjacent the sweep of the third paddle 113; a second arm is disposed adjacent the sweep of the fifth paddle 115; a third static arm is disposed adjacent the sweep of the seventh paddle 117; a fourth static arm is disposed adjacent the sweep of the ninth paddles 119; and a fifth static arm is disposed adjacent the sweep of the eleventh paddles 121. Each static arm 90 is positioned - 19 adjacent the swept path of a support arm 172 to provide a surface against which material may be trapped and cut.

Referring to Figures 9 and 10, the paddles 111, 112, 113, 115, 117, 119, 121, 122 and arms 114, 116, 118, 120 are fixed to the rotating shaft 181 by a support arm 172. The support arm 172 comprises a rigid plate 162 which defines a shaft receiving aperture 164 at one end and is shaped to extend outwardly from the shaft 181. At the other end of the support arm 172, a paddle plate 165 is pivotally attached. The paddle plate 165 is held outwardly from one surface of the support arm 172 at the normal operating angle against a leaf spring 167. This leaf spring can be seen in further detail in Figure 13. In use, the paddle plate 165 remains in its normal operating position, however, should the plate 165 encounter an obstruction, the plate 165 deflects rearwardly to allow the paddle 111, 112, 113, 115, 117, 119, 121, 122 to continue to rotate within the container 180. The amount of deflection depends on the force applied by the leaf spring 167 but is typically between 30° and 50°. Deflector 174 is provided to protect the pivot area and spring 167 from adverse exposure to the material being mixed. One of the deflectors 174 acts as a stay to strengthen the support arm 172 and also increases mixing of material in the container 180.

One side of the support arm 172 is profiled as a blade surface 173 and, the blade surface 173 is operable to cut material against the square surfaces of the static arms 90.

The combined effect of the static arms 90 and the blade surfaces provided on the paddle support arms 172 rotating about the shaft 180 allows very coarse and fibrous - 20 material to be ingested by the mixing and dispensing apparatus.

Referring to Figure 13 the the spring is provided using a four leaf arrangement 131 bolted to the rigid plate 162.

It will be appreciated that an important feature of the invention is the scissor cutting action between the paddles and corresponding static arms. The blades as cutting faces may be provided on either arm or paddle or indeed on both. Deflection of the paddle on encountering an obstruction will not entirely stop the mixing process as the static arm will continue to mix passing material to some degree.

The biasing mechanism will return the paddle to an operational position as soon as the obstruction has passed or is removed.

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 modifications and alterations are possible within the scope of the invention.

Claims (32)

CLAIMS:

1. An apparatus for mixing and dispensing animal foodstuffs comprising a controllable dispensing outlet, a 5 mixing means for mixing material in the container provided by a plurality of paddles rotatably mounted within the container, at least one of the said paddles being moveable between an operating and a deflected position. 10

2. An apparatus as claimed in claim 1 wherein a shaft is mounted along a longitudinal axis of the container.

3. An apparatus as claimed in any preceding claim wherein the paddle is provided by a support arm and a 15 plate at the end of the arm.

4. An apparatus as claimed in claim 3 wherein the plate is pivotally secured to the support arm and adapted to deflect from an operating position.

5. An apparatus as claimed in claim 3 or claim 4 wherein the plate is angularly disposed at a predetermined angle with respect to the axis of rotation of the shaft. 25

6. An apparatus as claimed in any preceding claim wherein the paddle is biased towards the operating position by a spring mechanism.

7. An apparatus as claimed in claim 6 when dependent on 30 any of claims 3 to 5 wherein the spring mechanism is fixed at one end to the support arm and at the other end to a plate.

8. An apparatus as claimed in claim 6 or claim 7 35 wherein the spring mechanism includes a spring tensioning - 22 device to ensure the spring is biased to deflect only on encountering a major blockage or obstruction.

9. An apparatus as claimed in any of claims 6 to 8 wherein the spring mechanism includes a four leaf combination.

10. An apparatus as claimed in any preceding claim wherein each paddle includes a cantilever plate.

11. An apparatus as claimed in claim 10 wherein the cantilever plate is connected to a support arm at a point displaced from the centre of the plate.

12. An apparatus as claimed in claim 10 wherein the cantilever plate 10 is connected to a support arm at an end of the plate.

13. An apparatus as claimed in any of claims 3 to 12 wherein a support arm is provided with a blade adapted to cut material against fixed arms mounted within the container.

14. An apparatus as claimed in any of claims 2 to 13 wherein a plurality of static arms are secured in the container between a side wall and the shaft.

15. An apparatus as claimed in claim 14 wherein an end of a static arm is fixed to a side wall of the container and above a rotating shaft.

16. An apparatus as claimed in any of claims 2 to 15 wherein the or each support arm is provided with a blade adapted to cut material in the container. - 23

17. An apparatus as claimed in claim 16 wherein the static arms are arranged to provide a scissors action with the blades mounted on the support arms. 5

18. An apparatus as claimed in any of claims 14 to 17 wherein the static arm includes an orthonganal cutting edge.

19. An apparatus as claimed in any of claims 14 to 18 10 wherein the static blades are arranged to provide a scissors action with the blades mounted on the support arms .

20. An apparatus as claimed in any of claims 2 to 19 15 wherein the support arm incorporates a serrated edge.

21. An apparatus as claimed in any of claims 13 to 20 wherein the blade has a serrated edge. 20

22. An apparatus as claimed in claim 1 wherein the container is open at a top end thereof and comprises a rounded base for housing the shaft, front and end walls carried on the base and first and second side walls extending upwardly from the rounded base, and having a 25 dispensing outlet in one of the side walls.

23. An apparatus as claimed in claim 22 wherein the dispensing outlet is substantially adjacent the rounded base.

24. An apparatus as claimed in any preceding claim wherein the paddle is disposed at an operating angle of between 20° and 80° to the axis of rotation of a shaft mounted in a container to provide an even discharge 35 through the dispensing outlet. - 24 25. An apparatus as claimed in any preceding claim wherein the path swept by a paddle overlaps the path swept by an adjacent paddle. 26. A paddle for use with an apparatus for mixing and dispensing animal foodstuffs and like material comprising an open-topped container having a driven shaft in the container rotating along the container's longitudinal 10 axis, the shaft including a plurality of paddles, each paddle comprising a radial support arm mounted on the shaft at one end and having a pivotally mounted plate at the other end, the plate being biased toward an operating position and being deflectable on encountering an 15 obstacle. 27. An apparatus as claimed in any preceding claim incorporating a dispenser provided by a dispensing paddle. 20 28. An apparatus as claimed in claim 27 wherein the dispensing paddle is rotatably mounted within the container. 29. An apparatus for mixing and dispensing animal food

25. Stuffs comprising a container housing a rotatable shaft, a mixing means provided by a plurality of paddles carried on the shaft for mixing material in the container, the paddles being spaced apart and radially offset about a longitudinal axis of the shaft.

26. 30. An apparatus as claimed in claim 29 wherein at least one paddle is movable between an operating and a deflected position. 35

27. 31. An apparatus as claimed in claim 29 or claim 30 - 25 wherein adjacent paddles are radially offset by greater than 45°.

28. 32. An apparatus as claimed in claim 31 wherein adjacent 5 paddles are offset by between 65° and 80°.

29. 33. An apparatus as claimed in any of claims 29 to 32 wherein a paddle adjacent an end of the container is offset from an adjacent paddle by greater than 150°.

30. 34. An apparatus as claimed in claim 33 wherein the end paddle is offset from the adjacent paddle by between 175° and 180°. 5

31. 35. An apparatus substantially as herein described with reference to, and as shown in, the accompanying drawings.

32. 36. A paddle substantially as herein described with reference to, and as shown in, the accompanying drawings.