IES20020923A2 - A cement feed system - Google Patents

Abstract

A batching plant (1) is disclosed for use in the manufacture of concrete and like products. It comprises a mixer (2), a sand storage bin (3) and a stone aggregate storage bin (5). Conveyor means (4,6) are provided for delivering the sand and aggregate to the mixer (2). It includes a water storage tank (8), and means for delivering water from the water storage tank (8) to the mixer (2). A cement container (26) comprises a flexible bulk container (FIBC) (26) for storing a supply of cement. The container (26) has a discharge spout (28). A hoist (10) is provided for lifting the container (26) into an upright discharge position. The discharge spout (28) of the container is connected to an inlet (31) of an enclosed conveyor system (30), including an auger, for conveying cement from the discharge spout (28) of the container to a mixer (2). <Figure 1>

Description

Field of the Invention The invention relates to a system and apparatus for feeding cement to a cement batching plant.

Background to the Invention Batching plants for making concrete products are known. For example, it is known to provide batching plants at building sites for use in manufacturing concrete.

An example of such a batching plant is the “Mix-Master™” of Mac-Fab Systems Limited. This is a self-contained portable batching and mixing plant for concrete products. The plant may be delivered to and set up at a building site in a matter of hours. The plant has a bin for containing a supply of sand, a bin for containing a supply of stone aggregate and a bin for containing a supply of cement. There is also a water tank. The cement, sand stone and water are delivered to a pan mixer at desired ratios to manufacture concrete. The stone and sand are delivered from the respective bins by suitable conveyors and the cement is conveyed from the cement bin by means of an auger. The batching plant has a control unit to control operation of the supply of the sand, stone and cement and water to the pan mixer which incorporates a vibrator.

In the known batching plant sand and stone are loaded into the respective sand and stone bins by means of a front loader or skip mounted fork lift. This arrangement presents no problems. However, in the known batch plant the cement is supplied in 25 kg bags. These are carried by an operative up a ladder and emptied into the top of the cement bin. This is laborious because it requires up to 120 cement bags to fill the cement bin. Also, there is the disadvantage that the cement dust is dispersed into IPn709?3 Object of the Invention It is an object of the invention to provide an improved system and apparatus for supplying cement to a cement mixing apparatus. It is also an object of the invention to provide an apparatus for handling cement and transferring it to the mixer of a mixing plant.

Summary of the Invention The invention provides a cement delivery system comprising a flexible bulk container for storing a supply of cement, and having a discharge spout, a hoist for lifting the container into an upright discharge position, means for connecting the discharge spout of the container to an inlet of an enclosed conveyor system for conveying cement from the discharge spout of the container to a mixer .

Preferably, the conveyor system comprises a pipe having an inlet chute at one end to receive cement from the discharge spout of the container, an outlet nozzle at the other end for discharging the cement to a mixer, and a screw conveyor within the pipe for conveying the cement through the pipe. Suitably, the hoist comprises a gantry having a transverse guideway, lifting means, optionally a hydraulic ram, for raising and lowering the guideway substantially vertically of the gantry, and means, optionally a trolley, for moving the container substantially horizontally.

In accordance with another aspect, the invention provides a batching plant for use in the manufacture of concrete and like products, comprising a mixer, a sand storage bin and a stone aggregate storage bin, conveyor means for delivering the sand and aggregate to the mixer, a water storage tank, means for delivering water from the water storage tank to the mixer, a cement container, and means for conveying cement to the mixer, wherein the cement container comprises a flexible bulk container for storing a supply of cement, and having a discharge spout, means for maintaining the container in an upright discharge position, means for connecting the discharge spout of the container to an inlet of an enclosed conveyor system for conveying cement from the discharge IE0 2 09 2 j spout of the container to a mixer. Preferably, the system includes a hoist for lifting the container into the upright position, and a gantry for moving the container horizontally.

Brief Description of the Drawings One embodiment of the invention is hereinafter described with reference to the accompanying drawings wherein: Figure 1 is a front elevation of a cement batching plant in accordance with the invention; Figure 2 is a front elevation of a detail of the batching plant of Figure 1; Figure 3 is a perspective view of a part of Figure 2, showing a hoist and bulk container for cement; Figure 4 is a perspective view of the hoist of Figure 3.

Detailed Description of a Preferred Embodiment Referring to Figure 1 of the drawings this shows a cement batching plant. This is a portable plant for mixing cement, sand, stone aggregate and water to make concrete or the like. It may also be adapted for use in making other cement-like products such as mortar. The batching plant is portable so that it can be moved by lorry to a building site where it is used to produce concrete in the construction of houses, industrial and commercial buildings, roads, agricultural buildings and concrete products in general.

The batching plant 1 comprises a support structure 7 which supports a pan mixer 2 which operates in well known manner to mix cement, sand, stone aggregate and water to form concrete. The pan mixer 2 contains mixing arms which are rotatable, and are adapted to rotate at about speeds of about 22 r.p.m. The pan mixer 2 is mounted on three asymmetric rotational load-cells (not shown). A sand storage bin 3 is located to one side of the mixing pan 2 and is adapted, in well known manner, to contain a supply of sand which is conveyed from the sand bin by a conveyor 4 to the pan mixer 2. A stone aggregate storage bin 5 is located on the opposite side of the pan mixer and is adapted to contain a supply of stone aggregate for use in manufacturing concrete. The stone aggregate is supplied to the pan mixer 2 by means of a conveyor 6, in well known ΙΕ η 2 0973 manner. The bins 3 and 5 are mounted on a suitable support structure such that the batching plant can be dismantled and transported easily. A water tank 8 is located beneath the sand bin 3. The water tank 8 contains a water pump (not shown) and is adapted to contain up to about 700 litres of water to supply to the pan mixer 2 to make a concrete mix. It is designed to supply water at approximately 100 litres per minute. A water pump may also be used as a high pressure washer for cleaning the batching plant, after use.

The batching plant 1 is powered by a power unit 9 which may comprise a 30 kw diesel engine or an electric motor.

The invention provides a novel method and apparatus for supplying cement in powder or particulate form to the pan mixer 2.

The invention includes a gantry 10, which is most clearly shown in Figures 2 to 4, and which is located to one side of the batching plant. The gantry 10 comprises two, spaced-apart, upright guide members 11. The guides 11 are carried on a support plate 12 and may be bolted, or otherwise secured to the frame 7, for example by structural members 23. A horizontal transverse guideway 13, in the form of an I-section beam is mounted on a pair of slides 14 by means of horizontal plates 21. The slides 14 slide vertically in channels 15 of the guides 11 on roller bearings. The guideway 13 may be raised and lowered along the guides 11 by means of a hydraulic ram 16 which is operated by a hydraulic pump (not shown) in well known manner. Alternatively, an electric motor may be used to raise and lower the guideway 13.

A trolley 17 is mounted in the guideway 13 and has wheels 18 which engage with the guideway such that the trolley may move transversely and horizontally along the I-beam guideway 13.

The trolley 17 carries a plate 20 incorporating a hook which is adapted to engage with four straps 25 of a flexible bulk container 26. The flexible bulk container may be of the kind referred to as a flexible intermediate bulk container (FIBC). FIBC’s are ΙΕ η 2 09 7 3 commercially available and are generally manufactured from a synthetic woven material, for example polypropylene. FIBC’s are supplied, for example by Synthetic Packaging Limited, of Clara, Ireland under the tradename “Easypack”. FIBC’s are also produced by Hydro Packaging AS. It is known to use FIBC’s to package cement, but in known systems the cement is released from the FIBC’s by slitting the underside of the container, which is hazardous because it releases cement dust into the atmosphere.

In accordance with the invention the flexible bulk package container 26 has a top filling spout 27 in the upper wall thereof, and a discharge spout 28 in the bottom wall thereof. The bag 26 suitably has an integral liner, for example a polyethylene liner, to prevent cement powder from escaping from the container.

In use, the bulk container 26 is filled with cement, in well known manner, at a cement factory and is delivered by truck to the site where the batching plant is in operation. The guideway 13 is lowered such that the hook 20 can engage with the lifting loops 25 on the top of the container 26. The guideway 13 is then raised to the position shown in Figure 2 to lift the bulk container 26 from the truck. When delivered, the filling spout 27 and discharge spout 28 of the bulk container 26 are closed by straps in well known manner.

After the bulk container 26 has been lifted from the truck, it is moved transversely, by means of the trolley 17 and hook 20 to the location shown in Figures 2 and 3 where it is positioned immediately above a conveyor for the cement. The trolley 17 may be moved manually by pulling the container 26 along the guideway 13. Alternatively, it could be powered, either electrically or hydraulically.

The discharge spout 28 is provided with two straps 29 which are used to close the spout. The end of the discharge spout 28 is connected to an inlet chute 31 of a conveyor 30. The discharge chute 28 is adapted to fit tightly about an annular inlet flange 32 of the chute 31. The discharge chute 28 is held in position on the inlet flange by means of a quick release clamp 33 which is secured to the conveyor. The clamp 33 is operated by an over centre cam lever to secure a perfect and tight fit of the discharge ΙΕ θ 2 09tJ spout 28 around the flange 32. When the chute is put in position the straps 29 may be opened to release cement into the chute 31. The straps 29 are, for example, 12 mm flexible straps which are sewn into the chute 31. The first strap is used to close the chute 31, which in the closed position is folded back and held by the second strap 29, for additional tying security.

From the inlet chute 31 the cement is conveyed through an enclosed, preferably sealed, pipe 35 by means of the screw conveyor or auger 36 disposed co-axially of the pipe 35. The screw conveyor 36 conveys the cement to the opposite end of the pipe 35 from where it is discharged through a discharge nozzle 37 into the pan mixer 2. The screw conveyor 36 is powered by an electric motor 38 (see Fig. 2). In this way, the powdered cement may be discharged from the flexible bulk container 26 to the mixing pan without any release of cement dust or powder into the atmosphere.

The flexible bulk container 26 is provided with a bag massager 39 to encourage release of the cement through the discharge spout 28. The bag massager is a flat nylon strap 39, having a ratchet to tighten the strap on the flexible bulk container 26. Tightening of the strap 39 will break-up any compacted cement in the container 26, to ensure a continuous flow down the spout 28. The screw conveyor 36 is capable of transporting the cement from the flexible bulk container to the mixing pan 2 at a rate of approximately 200 kg in 30 seconds.

The batching plant 1 has a control console 40, at which an operative may stand or sit. The control console 40 has a plurality of levers (or other controls) to operate the cement screw conveyor (auger) 30, the sand conveyor 4, the stone aggregate conveyor 6, the water pump, and the rotating arms/vibrator of the pan mixer 2. All of the materials are accurately weighed by three equally positioned load cells designed for rotational movement with digital read-out on the control panel 40 displaying the weight of material in the pan mixer 2. It takes 25 seconds approximately to discharge 0.5 cubic meter of well mixed concrete. The plant 1 mixes about 1200 kg concrete per batch. ΙΕ η 2 09 ? J The words “comprises/comprising” and the words “having/including” when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

From the foregoing, it will be apparent that numerous modifications and variations can be effected without departing from the true spirit and scope of the novel concept of the present invention. It will be appreciated that the present disclosure is intended to set forth the exemplifications of the invention which are not intended to limit the invention to the specific embodiments illustrated. The disclosure is intended to cover by the appended claims all such modifications as fall within the scope of the claims.

Where technical features mentioned in any claim are followed by reference signs, these reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly, such reference signs do not have any limiting effect on the scope of each element identified by way of example by such reference signs.

It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

Claims (5)

Claims

1. A cement delivery system comprising a flexible bulk container (26) for storing a supply of cement, and having a discharge spout (28), a hoist (10) for lifting the container (26) into an upright discharge position, means for connecting the discharge spout (28) of the container (26) to an inlet (31) of an enclosed conveyor system (30) for conveying cement from the discharge spout (28) of the container (26) to a mixer (2).

2. A system as claimed in Claim 1, wherein conveyor system (30) comprises a pipe (35) having an inlet chute (31) at one end to receive cement from the discharge spout (28) of the container (26), an outlet nozzle (37) at the other end for discharging the cement to a mixer (2), and a screw conveyor (36) within the pipe (35) for conveying the cement through the pipe.

3. A system as claimed in Claim 1, wherein the hoist comprises a gantry (10) having a transverse guideway (13), lifting means, optionally a hydraulic ram (16), for raising and lowering the guideway (13) substantially vertically of the gantry (10), and means, optionally a trolley (17), for moving the container (26) substantially horizontally.

4. A batching plant (1) for use in the manufacture of concrete and like products, comprising a mixer (2), a sand storage bin (3) and a stone aggregate storage bin (5), conveyor means (4, 6) for delivering the sand and aggregate to the mixer (2), a water storage tank (8), means for delivering water from the water storage tank (8) to the mixer (2), a cement container (26) and means (36, 35) for conveying cement to the mixer (2), wherein the cement container comprises a flexible bulk container (26) for storing a supply of cement, and having a discharge spout (28), means for maintaining the container (26) in an upright discharge position, means for connecting the discharge spout (28) of the container to an inlet (31) of an enclosed conveyor system (30) for conveying cement from the discharge spout (28) of the container to a mixer (2). ΙΕ η 2 0973

5. A cement delivery system and/or a batching plant substantially as hereinbefore described with reference to, and as illustrated in, the accompanying drawings.