GB2419552A

GB2419552A - Screening apparatus

Info

Publication number: GB2419552A
Application number: GB0522005A
Authority: GB
Inventors: Ronald Gill
Original assignee: GRYBROOK Ltd
Current assignee: GRYBROOK Ltd
Priority date: 2004-10-30
Filing date: 2005-10-28
Publication date: 2006-05-03
Anticipated expiration: 2025-10-28
Also published as: GB0424148D0; GB0522005D0; GB2419552B

Abstract

A screening apparatus 1 comprises a stationary outer drum 5 and an inner rotatable drum 10 pivotally 7 mounted on a stand 2. The inner drum 10 has perforated walls so as to allow the passage of material in to the cavity between the drums. Outer drum 10 has an outlet opening in its wall and at one end as well as a flared inlet / frusto-conical flange 11. Rotating inner drum 10 is powered by a hydraulic motor 9 driven by either a hydraulic pump or a petrol, diesel or electric motor. Other elements include support ring 6, outer drum base 8, pump return lines 15, 16, apparatus base 3, transport wheels 4, side plates 20 and drive arm 18.

Description

SCREENING APPARATUS

This invention relates to screening apparatus and is particularly concerned with the separation of oversize materials from finer materials.

Separation by screening has long been known. Where considerable tonnages of materials such as soil aggregates, coal, skip waste materials, demolition waste etc. are involved, it is economic to transport such materials in bulk to dedicated screening plants, where the materials can be separated into coarse and fine fractions or intermediary medium fractions, to suit either a further use of the fractions, or to allow a further treatment of the fractions.

When smaller amounts of material need to be separated into their fractions, it is ordinarily so that hand sieves or riddles or hand operated screening apparatus are used, making the task of handling reasonable amounts of materials most arduous.

The objection of the present invention is to provide screening apparatus that is portable and able to be taken to the location of material to be separated, that is power driven, and easily operated by a single operative.

According to the present invention, screening apparatus comprises a stationary outer drum mounted for pivotal movement on a stand, an opening in the outer drum wall to serve as an outlet, an open end to the outer drum and an inner drum rotatably mounted concentrically within the outer drum and with an open end in close proximity to the open end of the outer drum, the wall of the inner drum being perforated to allow the passage of material of a predetermined size, and there being a means to cause the inner drum to rotate.

Preferably, the stationary outer drum is mounted on the stand such that when in its operative position, its longitudinal axis is angularly disposed and its open end, with that of the inner drum, is upwardly facing, the outer drum being able to be pivoted to a position where the longitudinal axis is again inclined but with the open end of the outer and inner drums downwardly facing.

Further preferably, the inner drum has a frusto-conical flange extending from its open end to ease the loading of material into the inner drum.

Any suitable drive means can be used to rotate the inner drum, but desirably, its axle extends through the base of the stationary drum to a hydraulic motor, driven by a hydraulic pump, itself driven by such as an electric or a petrol engine. With such an arrangement, switch means can be provided on the hydraulic pump to connect the pump to a tilting mechanism for the stationary drum.

Thus, in its condition ready for use, material can be placed in the rotatable drum such as by way of a shovel, or by way of such as a mechanical digger or excavator, and the inner drum rotated. During its rotation small or fine pieces or particles of the material pass through the perforations in the wall of the inner drum, to collect in the outer drum, from where they fall through the opening in the wall of the outer drum and to the floor to one side of the screening apparatus, from where it can periodically be removed. When reasonable amounts of larger pieces of material have gathered in the inner drum, the switch on the hydraulic pump can be activated to allow the inner drum to continue to rotate and simultaneously cause a pivotal movement of the drums to bring their open ends to a downwardly facing position to deposit the collected larger pieces of material on the ground to the opposite side of the apparatus, from where it can periodically be removed.

To ensure the removal of material from within the stationary drum, blade means can be provided on the outer face of the rotatable drum, to scrape along the inner face of the outer drum and direct any adhering material towards the outlet opening in the outer drum.

The inner drum may be of plate metal or solid plastics material, suitably drilled or otherwise formed with perforations of a required size, and equally may be a wire mesh drum with apertures of a required size.

Ideally, the stand for the drums is provided with transport wheels and a handle, and such that an operative can locate the apparatus at a required location on site. Being driven by a petrol, diesel or electric motor, it can operate independently in remote locations, and the apparatus is ideal for such as market gardeners who frequently need to sieve several tons of soil to remove stones, and builders/contractors who frequently need to sieve aggregates and rubble to separate useable for unusable components. Equally the apparatus can be taken and used at such as spoil heaps to separate out useable coal.

In its simplest form of construction, the apparatus of the invention employs manual switching arrangements to bring about the rotation of the inner drum and the tilting of the inner and outer drums It is however feasible to provide remotely controlled switch means associated with the hydraulic pump, and for an operative to have a remote control means, such that in the circumstance where an operative is the driver of such as a mechanical digger or excavator, the apparatus can be loaded and operated by the operative who would not have to leave the cab or the seating arrangement on a mechanical digger or excavator.

One embodiment of the invention will now be described with reference to the accompanying drawings in which Figure 1 is a side elevation of screening apparatus in accordance with the invention in its operative condition; Figure 2 is a rear elevation of Figure 1, Figure 3 is a plan view of Figure 1; and Figure 4 corresponds to Figure 1 but shows the screening apparatus in a discharging condition.

In the drawings, screening apparatus 1 has a stand 2 extending from a base 3 provided with transport wheels 4 to allow the apparatus to be moved from location to location.

A non-rotational outer drum 5 is provided attached to an encircling support ring 6, the ring having a pivotal attachment 7 to connect the outer drum 5 to the stand 2. Externally of the base 8 of the drum 5 is a hydraulic motor 9 with a drive shaft extending into the drum 5 and to which is attached an inner rotatable drum 10 of a smaller diameter than the fixed drum, the rotatable drum 10 having a flared entrance 11 to ease the placement of material into the rotatable drum Flexible hydraulic supply and return lines 12, 13 connect the hydraulic motor 9 to a hydraulic pump 14 located on the screening apparatus base 3, the hydraulic pump 14 also having supply and return lines 15, 16 extending to a double acting piston and cylinder unit 17 connected to a drive arm 18 secured to the pivotal connection of the outer drum 5 to the stand 2.

The rotatable inner drum 10 has perforations over its periphery of a size to suit the screening operation that is to be performed, and the base of the non-rotatable outer drum 5 has a large aperture 19 in its lower half.

Thus, with the screening apparatus I in the condition shown in Figure 1, and with the hydraulic motor 9 rotating the inner drum 10, material to be screened can be loaded into the inner drum, and as the inner drum rotates, that material is tumbled, the result of which is that the finer materials pass through the perforated periphery and into the space between the inner and outer drums, to fall to the ground through the aperture 19.

Periodically, as shown in Figure 4, and when it is evident that the inner drum is filling up with coarse materials of a size incapable of passing through the apertures, the hydraulic piston and cylinder unit 17 is activated to cause the outer and inner drums to pivot about their connection to the stand 2, to cause coarse materials to be tipped from the inner drum on to the ground in front of the screening apparatus. The segregated finer and coarser materials can then be separately removed for disposal, or for subsequent usage for which the finer or the coarser segregated fractions are suited.

To contain the materials falling from the fixed drum and ejected from the rotating drum, the apparatus can have side plates 20 secured to the base 3 of the apparatus.

Claims

1. A screening apparatus comprising a stationary outer drum mounted for pivotal movement on a stand, an opening in the outer drum wall to serve as an outlet, an open end to the outer drum and an inner drum rotatably mounted concentrically within the outer drum and with an open end in close proximity to the open end of the outer drum, the wall of the inner drum being perforated to allow the passage of material of a predetermined size, and there being a means to cause the inner drum to rotate.

2 A screening apparatus as in Claim 1, wherein the stationary outer drum is mounted on the stand such that when in its operative position, its longitudinal axis is angularly disposed and its open end, with that of the inner drum, is upwardly facing, the outer drum being able to be pivoted to a position where the longitudinal axis is again inclined but with the open end of the outer and inner drums downwardly facing.

3. A screening apparatus as in Claim 1 or Claim 2, wherein the inner drum has a frusto-conical flange extending from its open end to ease the loading of material into the inner drum.

4 A screening apparatus as in any of Claims 1 to 3, wherein an axle on the inner drum extends through the base of the stationary drum to a hydraulic motor, driven by a hydraulic pump.

5. A screening apparatus as in Claim 4, wherein the pump is driven by such as a petrol, diesel or electric motor

6. A screening apparatus as in any of Claims I to 5, wherein the outer drum is pivotally mounted on a stand and tilting mechanism provided.

7. A screening apparatus as in Claim 6 when appended to Claim 4, wherein the hydraulic pump is connected to the tilting mechanism via an actuating switch.

8. A screening apparatus as in any of Claims I to 7, wherein blade means are provided on the outer face of the rotatable drum, to scrape along the inner face of the outer drum and direct any adhering material towards the outlet opening in the outer drum.

9. A screening apparatus as in any of Claims 1 to 8, wherein the stand for the drums is provided with transport wheels and a handle.

10. A screening apparatus as in any of Claims I to 9, wherein manual switching arrangements are provided to bring about the rotation of the inner drum and the tilting of the inner and outer drums.

11. A screening apparatus as in any of Claims 1 to 9, wherein remotely controlled switching means are provided to bring about the rotation of the inner drum and the tilting of the inner and outer drums, whereby rotation and tilting can be activated by a remote operative.

12 A screening apparatus substantially as hereinbefore described with reference to the accompanying drawings.