GB1580788A - Concrete mixing - Google Patents

Description

(54) IMPROVEMENTS IN OR RELATING TO CONCRETE MIXING (71) I, PETER FRANCIS BATES, of 23A Station Approach, Hayes, Kent, a British Subject do hereby declare the invention, for which I pray that a patent may be granted to me, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to equipment for mixing concrete, mortar, and the like, and in particular to a vehicle equipped for borh carrying the necessary materials separately and mixing them when desired. The term concrete as used hereinafter should be construed as including mortar and other similar materials which may be required to be mixed and delivered in bulk to a site where they are to be used.

Known vehicles capable of delivering concrete ready for use at a building site comprise a large-capaciry rotatable mixing drum mounted on the vehicle chassis. The invariable practice when making deliveries of concrete with such known vehicles is for the materials to be placed in the mixing drum at a depot where they are stored in large quantities. The vehicle is then driven to the site where the concrete is required for use, and during the journey the mixing drum is rotated continuously, thereby produång an intimate mixture of the ingredient materials in the drum and at the same time, by virtue of the continuous agitation caused by drum rotation, preventing the concrete mixture from setting prematurely into a solid mass.

Such a practice has a number of disadvantages from the point of view of the user of the concrete so produced. One major disadvantage is that the knows vehicles are invariably of large capacity, for example 10 cubic yards or more, and they are therefore unsuitable for deliveries of small quantities of concrete such as for example 1 cubic yard.

At present, therefore, a user requiring only a relatively small quantity of concrete at one time must either provide a portable, small capacity, concrete mixer at the site where concrete is required, or mix the conrete by hand. Both of rhese possibilities have obvious disadvantages.

A further disadvantage of the practice referred to above is that the depot, where mix ing necessarily commences, will be remote from the site where concrete is required, possibly by a considerable distance. Furthermore, by virtue of the large capacity of the mixing drum, and in order to make the most economic use of the vehicle, it may be necessary for the vehicle to make deliveries from a single load to more than one site, thereby increasing the journey time to the last site visited. As noted above, the continuous rotation of the mixing drum will prevent the mixture setting prematurely into a solid mass.However, the chemical reactions which result in setting of rhe concrete commence as soon as mixing of the materials begins, and furthermore the rate of such reactions is increased considerably in response to increased intimacy of mixing resulting from rotation of the drum throughout rhe journey. Thus, if the journey time has been considerable, the user may be provided with concrete which will set very rapidly before it can be placed in the desired position.

This disadvantage can be alleviated by known retarding agents, but the use of these may in turn carry certain disadvantages.

There thus exists a requirement for a means of providing concrete mixed and ready for use at a site remote from the depot where the ingredient materials are stored, in rela tively small quantities and freshly mixed.

According to the present invention, mobile equipment for mixing and delivering concrete at a site where it is required for use com prises a vehicle to which there are perman ently fixed a tank for containing a supply of water, a loading platform for solid bulk materials, and a rotary mixer mounted on the vehicle at the rear of the loading platform, the mixer provided with a rotatable drum having an open end, and being so mounted that the rotational axis of the drum is in a substantially vertical plane, the drum also being capable of being moved between a first position in which its open end is directed towards the loading platform and a second position in which the open end is directed away from the loading platform towards the ground to the rear of the vehicle.

The vehicle will normally be self-propelled, but could conceivably be in the form of a trailer for towing behind a self-propelled vehicle.

The rotary mixer can conveniently be a concrete mixer of conventional type having a rotatable drum and is advantageously provided with its own power source such as a petrol or diesel engine separate from the engine which propels the vehicle.

In a preferred arrangement, the drum is capable of being swung about a horizontal axis between the said first and second positions.

One embodiment of the invention will now be described by way of example only with reference to the drawings accompanying rhe provisional specification in which Fig. 1 is a perspective view of equipment in accordance with the invention, and Fig. 2 is a side elevation of the equipment shown in Fig. 1.

As shown in the drawings, a vehicle generally indicated as 1 is provided with a driving cab 2 and has a rigid chassis one member of which is indicated at 3. Mounted on the chassis is a load-carrying body comprising a loading platform 4, side panels 5 and 6, a rear panel 7, and a sloping front panel 8.

Also mounted on the chassis is a rigid rearward extension frame, comprising beams 9, 10, 11 and 12 welded together to form a mounting for a conventional concrete mixer generally indicated as 13. The concrete mixer 13 comprises a subdrame 14 in which a mixer drum 15 is mounted for rotation about an axis which falls in a vertical fore-and-aft plane of the vehicle. The drum is rotatable by means of a diesel engine (not shown) housed within a casing 16. The drum 15 is also capable of being swung about a horizontal axis transverse of the vehicle by means of handwheel 17 through gearing (not shown) housed in a casing 19 mounted on sub-frame 14.By this means the drum can be swung from a first position in which its open end is directed towards the loading platform 4 to a second position in which its open end is directed towards the ground to the rear of the vehicle.

A locking device 20 acting on the handwheel 17 is provided by which the drum can be locked in any one of a number of positions as desired.

At the front of the loading platform, just in front of the sloping panel 8 there is provided a locker accessible from the exterior of the vehicle by a door 21, in which tools etc. may be stored.

Immediately above the locker there is provided a rectangular water tank 22 having a pipe or hose 23 connected to the bottom thereof and terminating near the rear of the loading platform in a tap 24. The top 25 of the tank 22 acts as a shelf. Alternatively, to provide an increased tank capacity, the locker and its door 21 may be dispensed with, and the tank 22 may then extend from the level of the loading platform 4 to the top 25.

In use of the vehicle, a supply of water is placed in the water tank 22 and a supply of sand or ballast is placed on the loading platform 4 at a storage depot. Cement in bags also collected froml the depot can conveniently be stored separately from the sand or ballast on the shelf 25. The vehicle is then driven to the site at which concrete etc. is required and the mixer drum 15 is swung to face the loading platform 4 and locked in position. The necessary ingredient materials in rhe correct proportions are taken from those stored on the vehicle and placed in the drum 15, and the engine of the mixer is started to rotate the drum and mix the concrete ingredients together.When mixing is complete, the drum is swung rearwardly by means of hand wheel 17, so that the concrete may be discharged either to the ground or for example to a wheelbarrow below.

The arrangement described thus far provides water to the tap 24 by gravity feed from the tank 22, and clearly without placing the tank 22 at an excessive height it is not possible with this arrangement to feed the water directly from the tap into the mixer drum especially when the level of water in the tank is low and/or the base of the tank is level with the loading platform 4. In a preferred embodiment, therefore, a pump (not shown) is provided in the hose 23. Such a pump is conveniently housed under the sloping front panel 8, where it will be protected from damage. The pump is preferably electrically powered, e.g. from the vehicle battery, and may for example be actuable by means of a robust switch located on the panel 5 or the panel 7 close to the tap 24 for ease of operation. In this event, it will be necessary for the operator to operate the switch whenever water is required, after opening the tap 24. Alternatively a pressure-sensitive switch of known form could be provided in the section of hose 23 between the pump and the tap, to control the pump so that the pump operates only in response to opening of the tap.

In practice it may be found necessary to situate the tap 24 so that it is close to the drum 15 in its forward position, and damage to the tap can hence result from accidental contact of the tap with the rim of the drum.

In order to avoid the risk of such damage, it is preferred that the tap is provided with a length of flexible pipe, e.g. rubber or plastic hose, on its outlet side, such flexible pipe being directed towards the interior of the drum in its forward position, and being easily and cheaply replaceable. In a further modification, the pipe 23 opens into a T-piece, each branch of the T-piece being terminated in a tap such as 24. One branch is then directed towards the mixer drum 15 as described above, whilst the other branch terminates in a flexible hose which can be directed at will for washing down the load platform or other areas as desired.

As will readily be appreciated, the arrangements in accordance with the invention as described permit rhe convenient mixing on site of large or small quantities of concrete as reqiured, and in all cases the concrete can be freshly mixed at the required time.

WHAT I CLAIM IS: 1. Mobile equipment for mixing and delivering concrete at a site where it is required for use comprising a vehicle to which there are permanently fixed a tank for containing a supply of water, a loading platform for solid bulk materials, and a rotary mixer mounted on the vehicle at the rear of the loading platform, the mixer being provided with a rotatable drum having an open end and being so mounted that the rotational axis of the drum is in a substantially vertical plane the drum also 'being capable of being moved between a first position in which its open end is directed towards the loading platform and a second position in which the open end is directed away from the loading platform towards rhe ground to the rear of the vehicle.

2. Mobile equipment according to claim 1 in which the vehicle is selfropel1ed.

3. Mobile equipment according to claim 1 or claim 2 in which the drum is capable of being swung about a horizontal axis from the said first position to the said second position.

4. Mobile equipment according to any one preceding claim comprising a pipe connected to the tank and terminating in a tap from which water contained in the tank can be directed towards the rotary mixer.

5. Mobile equipment according to claim 4, in which a pump is provided in the pipe.

6. Mobile equipment according to claim 5 in which the pump is electrically actuable.

7. Mobile equipment according to claim 6 in which the pump is actuable by a manually operable switch.

8. Mobile equipment according to claim 6 in which the pump is actuable by a pressure sensitive switch connected to the pipe between the pump and the tap, the arrangement being such that the pump operates only in response to opening of the tap.

9. Mobile equipment according to any one of claims 4 to 8 in which the tap is provided with a length of flexible pipe on its outlet side.

10. Mobile equipment according to any one of claims 4 to 9 in which the pipe opens into a T-piece, each branch of the T-piece being terminated in a tap, the outlet of one tap being directed towards the rotary mixer and the outlet of the other tap being directed at will be way of a length of flexible hose connected thereto.

11. Mobile equipment substantially as hereinbefore described with reference to the drawings filed with the provisional specification.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (11)

**WARNING** start of CLMS field may overlap end of DESC **. cheaply replaceable. In a further modification, the pipe 23 opens into a T-piece, each branch of the T-piece being terminated in a tap such as 24. One branch is then directed towards the mixer drum 15 as described above, whilst the other branch terminates in a flexible hose which can be directed at will for washing down the load platform or other areas as desired. As will readily be appreciated, the arrangements in accordance with the invention as described permit rhe convenient mixing on site of large or small quantities of concrete as reqiured, and in all cases the concrete can be freshly mixed at the required time. WHAT I CLAIM IS:

1. Mobile equipment for mixing and delivering concrete at a site where it is required for use comprising a vehicle to which there are permanently fixed a tank for containing a supply of water, a loading platform for solid bulk materials, and a rotary mixer mounted on the vehicle at the rear of the loading platform, the mixer being provided with a rotatable drum having an open end and being so mounted that the rotational axis of the drum is in a substantially vertical plane the drum also 'being capable of being moved between a first position in which its open end is directed towards the loading platform and a second position in which the open end is directed away from the loading platform towards rhe ground to the rear of the vehicle.

2. Mobile equipment according to claim 1 in which the vehicle is selfropel1ed.

3. Mobile equipment according to claim 1 or claim 2 in which the drum is capable of being swung about a horizontal axis from the said first position to the said second position.

4. Mobile equipment according to any one preceding claim comprising a pipe connected to the tank and terminating in a tap from which water contained in the tank can be directed towards the rotary mixer.

5. Mobile equipment according to claim 4, in which a pump is provided in the pipe.

6. Mobile equipment according to claim 5 in which the pump is electrically actuable.

7. Mobile equipment according to claim 6 in which the pump is actuable by a manually operable switch.

8. Mobile equipment according to claim 6 in which the pump is actuable by a pressure sensitive switch connected to the pipe between the pump and the tap, the arrangement being such that the pump operates only in response to opening of the tap.

9. Mobile equipment according to any one of claims 4 to 8 in which the tap is provided with a length of flexible pipe on its outlet side.

10. Mobile equipment according to any one of claims 4 to 9 in which the pipe opens into a T-piece, each branch of the T-piece being terminated in a tap, the outlet of one tap being directed towards the rotary mixer and the outlet of the other tap being directed at will be way of a length of flexible hose connected thereto.

11. Mobile equipment substantially as hereinbefore described with reference to the drawings filed with the provisional specification.