GB2090150A - Mixing apparatus - Google Patents

Abstract

Apparatus for mixing material comprising a trough (4) in which is disposed mixing means comprising a generally horizontal rotatable shaft (5) carrying a series of paddles (6) which are spaced one from the other and inclined to cause movement of the material in the trough axially of the shaft during mixing. In one embodiment (Fig. 4) horticultural peat etc., discharged from the trough up a tube (11) passes through a chute (12) over the trough so enabling pots to be filled and allowing surplus peat to fall back into the trough. <IMAGE>

Description

SPECIFICATION Mixing or stirring apparatus The invention relates to apparatus for mixing or stirring materials such as discrete or particulate or liquid materials, more particularly, but not exclusively, for use in horticulture for mixing or stirring a growing medium such as peat, sand and loam.

It is known to provide a screw auger mounted in a trough in order to mix or stir horticultural peat but I have found that such devices tend to destroy the structure of the peat thus rendering it less suitable or useless for its intended purpose. It is an object of my invention to obviate or mitigate against this disadvantage of known devices.

According to the invention, there is provided apparatus for mixing or stirring materials comprising a mixing or stirring trough in which is disposed stirring or mixing means comprising a generally horizontal rotatable shaft carrying at least one series of paddles, the paddles in the or each series being spaced one from the other and being inclined to cause movement of the material in the trough axially of the shaft during mixing or stirring Preferably the arrangement is such that two series of paddles are provided, one series of paddles conveying the material in the opposite direction to the other series of paddles.Preferably, the paddles in the or each series are staggered one from the other both rotationally and axially and preferably they are arranged so that they are axially contiguous so that no portion of the material in the trough remains unstirred and that the portion of the trough swept by any one paddle is substantially undisturbed by any other paddle.

Preferably the two series of paddles are arranged se that the material being stirred or mixed is conveyed to a central position from which the material may be discharged by any suitable means such for example as a screw auger or belt conveyor From another aspect, the invention provides apparatus for mixing or stirring discrete or particulate material for use more particularly in filling pots or other containers comprising a trough in which the material is mixed or stirred, means for conveying mixed or stirred material from the trough and means for discharging the conveyed material into a suitably positioned container, the arrangement of the discharge means being such that surplus discharged material is returned by gravity to the trough.

The invention is diagrammatically illustrated by way of example in the accompanying drawings in which Figure 1 is a side elevation of a mobile mixing and/or stirring apparatus; Figure 2 is a sectional side view of part of the mixing apparatus of Figure 1; Figure 3 is a sectional end elevation of the apparatus of Figures 1 and 2; and Figure 4 is a perspective view of a static mixing and/or stirring apparatus in accordance with the invention.

In the drawings and referring more particularly to Figures 1 to 3 thereof, there is shown mixing and/or stirring apparatus for mixing or stirring horticultural peat e.g. to blend it with sand and/or loam or to mix it with a plant nutrient or water, comprising a generally horizontal trough 4 having a rounded bottom 1 3 and an open top 14 in which is mounted a generally horizontal rotatable shaft 5 carrying paddles 6. The shaft is driven in rotation in the trough by means of an electric motor 1. For mobility, the trough is mounted on a pair of wheels 2 and is supported by a prop 1 5.

As can be seen in Figure 1 of the drawings, the open mouth 14 of the trough is surrounded by a performated pipe 7 which acts as a sprinkler system by means of which for example, water may be added to the material being mixed. As can also be seen in Figure 1 of the drawings, the end of the shaft 5 remote from the motor 1 is supported by a bearing 3, carried by the end wall of the trough.

The paddles 6 are supported on the shaft 5 by means of arms 8 which are twisted adjacent their free ends so that the paddles are inclined at substantially 450 with respect to the axis of the shaft. In this way, on rotation of the shaft, the material in the trough is conveyed by the paddles axially of the trough. In this embodiment, the shaft carries eight paddies each staggered at an angle of 9O0 from the adjacent paddle or paddles and all of which are inclined to convey the material towards the centre of the trough. For this purpose, the four paddles at one end of the drum are inclined in one direction while the four paddles at the other end of the drum are inclined substantially normally to the first set of paddles to convey the material in the opposite direction.As can be seen best from Figure 2 of the drawings, the ends of the paddles are axially adjacent one another, that is to say the paddles do not overlap axially. In this way the material at any position in the trough is agitated by a single paddle until the paddle conveys the material axially of the drum to an extent sufficient to be acted on by the next adjacent paddle.

The mixed or stirred material may be removed from the trough in any convenient fashion e.g. by means of a centrally mounted screw conveyor or belt conveyor (not shown in the drawings).

Referring to Figure 4 of the drawings, there is shown stirring/mixing apparatus of the kind generally described above except that the apparatus of Figure 4 is stationarily mounted on a stand 9. In this embodiment, the mixed or stirred material is removed from the trough 4 through a vertical screw conveyor (not shown) mounted in a tube 11 which communicates with the trough and is discharged from the top of the screw conveyor into a chute 12 for the purpose of filling pots or other containers with the mixed or stirred material.

Since the end of the chute 12 is disposed above the open top of the trough 4, surplus material is returned directly to the trough by gravity and is not wasted. As can be seen in Figure 4, the top of the trough is covered by a grill 10 for safety reasons.

Claims (7)

1. Apparatus for mixing or stirring materials comprising a mixing or stirring trough in which is disposed stirring or mixing means comprising a generally horizontal rotatable shaft carrying a series of paddles which are spaced one from the other and inclined to cause movement of the material in the trough axially of the shaft during mixing or stirring.

2. Apparatus according to claim 1, comprising two series of paddles, the arrangement being such that one series of paddles conveys the material in the opposite direction to the other series of paddles.

3. Apparatus according to claim 2, wherein the two series of paddles are arranged so that the material being stirred or mixed is conveyed to a central position and comprising means for discharging the mixed or stirred material from the trough.

4. Apparatus according to claim 3, wherein the discharge means is arranged such that surplus discharged material is returned by gravity to the trough.

5. Apparatus according to any preceding claim wherein the paddles in the or each series are staggered one from the other both rotationally and axially.

6. Apparatus according to any preceding claim wherein the paddles in the or each series are arranged so that they are axially contiguous so that no portion of the material in the trough remains unstirred and that the portion of the trough swept by any one paddle is substantially undisturbed by any other paddle.

7. Apparatus for mixing or stirring discrete or particulate material substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.