GB2228186A

GB2228186A - Floor cleaning apparatus

Info

Publication number: GB2228186A
Application number: GB8900714A
Authority: GB
Inventors: Donald Whitehead
Original assignee: NEOLITH CHEMICALS Ltd
Current assignee: NEOLITH CHEMICALS Ltd
Priority date: 1989-01-13
Filing date: 1989-01-13
Publication date: 1990-08-22
Also published as: GB8900714D0

Abstract

Floor cleaning apparatus especially suitable for cleaning the floor grids of paint spray booths comprises a cleaning head 2 provided with rotary sprayers for directing jets of water at the floor and supported by wheels 12, 14 on the floor and a frame 4 on which the cleaning head is pivotally mounted for pivoting about pivots X. A handle 24 may be secured to the frame and the latter may be supported on the floor by wheels 30. Each rotary sprayer may have nozzles arranged to direct water jets at the floor at an angle in the range 15 DEG - 45 DEG . The sprayer may be rotated by an air motor. <IMAGE>

Description

CLEANING APPARATUS This invention relates to apparatus suitable for (but not limited to) cleaning the floor of a paint spray booth.

A typical paint spray booth, as used in the motor industry for the spraying of vehicle bodies and panels, is a long room along which parts for painting are conveyed, usually by a drive arrangement which comprises a travelling chain which passes over the floor of the booth, usually guided in a channel.

The floor of a paint spray booth typically comprises a grid made up of parallel vertical slats, each slat being about 2.5cm in depth and about 3mm in width.

The spacing of the slats is about 8cm. The slats are inter-connected by an array of parallel rods extending at rightangles to the slats. The spacing of the rods is about 8cm.

In a paint spray booth, paint is typically applied to vehicle bodies and panels by spraying, sometimes manually and sometimes by robot. An air purification system employing a down draught operates, whereby paint particles which do not contact the vehicle parts may by drawn through the grid, into a water bed, which is circulated through a filtration and removal system. During a working shift, the grid tends to accumulate a layer of paint. The surface of the grid tends to become slippery, which can be a danger to operatives, and the working area becomes extremely messy.

Because of these problems it has become the industry practice to clean the grid at least once a day, and usually, at the end of each shift.

Cleaning of the grids of paint spray booths may be carried out by removing the grid for cleaning, or by cleaning in situ. The practice of removing the grid for cleaning is a common one. The parts of the grid may then be cleaned by stove cleaning or sand blasting. However, this method has the disadvantages that a spare set of grid parts are required so that a replacement grid can be assembled for use whilst the first grid parts are being cleaned, and requires a considerable amount of labour for the removal and replacement of the grid parts.

Cleaning in situ is typically carried out using a chemical paint stripper and/or multi-purpose cleaning machine having a cleaning head in which is mounted a rotatable water jet arrangement. The water jet arrangement typically comprises a single rotatable member having a pair of diametrical arms carrying nozzles. The nozzles are arranged such that water jets issue from them in a near-vertical direction. The spray jet arrangement is rotated about a vertical axis by the action of the water jets.

Although such machines are effective in cleaning horizontal surfaces, they are not very effective in cleaning grids, such as the type found on the floors of paint spray booths. In particular, the vertical sides of the grid slats, and especially the top parts of the sides, are not well cleaned. Moreover, when such a machine is passed over a floor grid in a paint spray booth, the water jets impinge forcibly on the water bed below, causing a great deal of splashing and a considerable amount of noise.

A further disadvantage in using such a machine to clean the floor grids of paint spray booths is that it is typically a fairly heavy and bulky unit and the cleaning head is rigidly carried on a boom, forwardly of a frame having a pair of axles. Whilst this arrangement is suitable for cleaning a perfectly horizontal surface, such as an airport runway, the machine is not well-suited for travelling up and down inclined surfaces, which are commonly formed in the floor of a paint spray booth.

The present invention will now be defined and described. In the following definitions and description the terms front, rear, and transverse, are used with reference to the travel of the cleaning apparatus of the invention in operation.

In accordance with a first aspect of the present invention there is provided apparatus for cleaning a floor, for example the floor grid of a paint spray booth, the apparatus comprising a cleaning head carrying a spraying means, the cleaning head having a pair of axles each of which carries at least one wheel for engaging the floor, one axle being located at or towards the front of the cleaning head and the other axle being located at or towards the rear of the cleaning head, the cleaning head being pivotally mounted on a frame about a pivot axis which is substantially parallel to the support axles.

The cleaning head is preferably pivotally mounted on the frame towards the rear of the cleaning head.

It is preferred that the cleaning head is pivotally mounted on the frame at a position intermediate the axles (without necessarily being in the plane therebetween).

Preferably, each axle of the cleaning head comprises a wheel whose circularly cylindrical floorengaging surface is of a length (ie., dimension in the axial direction) which exceeds the spacing of the uppermost parts of a standard floor grid, whereby when the apparatus is passed over such a grid in a direction parallel to those uppermost parts, each such wheel will engage and run on at least one such part, whereby the apparatus can be run smoothly over the grid without "cogging". Thus, the floor-engaging surface of each such wheel is suitably at least about 8cm in length. Although each axle may comprise two such wheels, located towards the respective transverse sides of the cleaning head, conveniently, each axle may have only one such wheel located substantially an equal distance from the respective transverse sides.

Suitably, the frame comprises two arms, the arms being connected to the cleaning head at or towards a respective transverse side thereof, the two connections defining the pivot axis of the cleaning head about the frame.

Preferably, the frame has its own independent support axle, substantially parallel to the axles of the cleaning head. The support axle suitably carries a wheel or wheels of large diameter relative to the wheels of the cleaning head. Conveniently, the support axle is constituted by two stub axles, carried by respective arms of the frame, and each carrying a wheel. Preferably, in use, the support axle of the frame and the pivot axis of the cleaning head about the frame lie in a plane substantially parallel to the floor.

The frame may comprise a handle by means of which the apparatus can be pushed.

Preferably, the cleaning head comprises a canopy beneath which is housed the spraying means, the canopy having downwardly extending side walls extending around its periphery to retain, beneath the cleaning head, liquid sprayed from the spraying means.

Preferably, the spraying means is such as to spray a liquid, which may, for example, be water or a water/detergent solution, towards the floor being cleaned, at a small angle thereto, for example an angle in the range 15-45 . Preferably, the spraying means is such as to spray the liquid towards the floor at an angle thereto in the range 17-30 .

In accordance with a second aspect of the present invention there is provided apparatus for cleaning a floor, for example, the floor grid of a paint spray booth, the apparatus comprising a wheeled unit comprising a cleaning head which carries a spraying means, the spraying means being such as to spray liquid, in use, towards a floor being cleaned, at an angle in the range 15#45O, preferably 17-30 .

Whilst the said wheeled unit which carries the novel spraying means may be of conventional type as used presently, preferably the wheeled unit is a cleaning head/frame arrangement as defined above in the first aspect of the invention.

In relation to the first and/or second aspect of the present invention, it is preferred that the spraying means comprises a rotatable spray head. Preferably, the spray head comprises one or more arms, suitably two arms, diametrically arranged. The end of each arm may comprise a plurality of spray outlets arranged to supply nonparallel liquid jets. In one effective embodiment the end of each of the two arms of a spray head carries two nozzles arranged to supply water jets at an obtuse angle to each other.

Preferably, a plurality of rotatable spray heads is provided. In one effective embodiment two spray heads are employed, located side-by-side across the cleaning head.

Preferably, the or each spray head is rotated by means other than, or additional to, the propulsive effect of the liquid jets, for example by means of an air motor.

Preferably, the means for rotating the or each spray head and the liquid supply for the apparatus are commonly controlled by the user. For example, when the means for rotating a spray head is an air motor a liquid supply valve may be under the pneumatic control of a pilot line taken from the pneumatic line to the air motor. Thus, in switching on the (or each) air motor the user also switches on the liquid supply.

Typically, the pressure of the cleaning liquid is at least 50MPa, unless the apparatus is used in conjunction with a chemical pre-treatment method, such as is described in our U.K. patent application entitled 'Chemical Treatment', filed concurrently with this application, when the pressure of the cleaning fluid may be lower. The liquid supply rate is suitably about 50150 litres per minute. The spray head rotation speed may typically be about 200-800rpm. When the chemical pre treatment is used effective cleaning with very short traverse times can be carried out using low water pressure and a high spray head rotation speed.

The cleaning apparatus of the present invention and the chemical pre-treatment method described in our co-pending U.K. application entitled 'Chemical Treatment', filed on the same day as the present application, (the contents of which are hereby incorporated by reference) are advantageously both used in a floor cleaning programme.

The invention will now be further described, by way of example, with reference to the accompanying drawings which: Fig. 1 is a side elevation of cleaning apparatus in accordance with the invention; Fig. 2 is a front elevation of the cleaning apparatus of Fig. 1; Fig. 3 is a schematic view of the underside of the cleaning head, showing the two spray heads and their respective spray patterns; Fig. 4 shows the arm of one of the spray heads in greater detail; Fig. 5 is an end view of the arm of Fig. 4; and Fig. 6 is a diagram showing the pneumatic circuit for the apparatus.

with reference to Figs. 1 and 2, the cleaning apparatus comprises a cleaning head 2 pivotally mounted about a pivot axis X to a wheeled frame 4. The cleaning apparatus is shown on a floor 6, which may, for example, be the grid of a paint spray booth.

The cleaning head is in the form of a canopy having an upper, flat, rectangular plate 8 and upright walls 10 extending downwardly from the plate 8, around its periphery. The dimensions of the cleaning head in this embodiment are 65cm (width transverse to direction of travel) by 35cm (width parallel to direction of travel) by 6cm (height of walls 10).

The cleaning head is supported on the floor by a pair of axles each of which carries a wide roller-type wheel of small (5cm) diameter. One such wheel 12 is located towards the front of the cleaning head and the other such wheel 14 is located towards the rear of the cleaning head. Each wheel has a cylindrical surface which may contact the floor, the length of that cylindrical surface being approximately 10cm.

Carried within the canopy of the cleaning head are two rotatable spray heads 16, indicated schematically in Fig. 2 and further shown in Figs. 3-5. The spray heads are supplied with water in standard manner and are powered by respective air motors of conventional type.

Each spray head is coupled to a water supply shaft via a high pressure rotating joint having rotary seals, above and below the inlet to the spray head, between the spray head and the shaft.

Each rotatable spray head has a pair of opposed arms 18 each of which carries at its end a pair of spray nozzles 20 (Fig. 5). The nozzles of each arm are so located as to direct a spray jet outwardly and downwardly, one from one side of the arm and the other from the other side of the arm, the spray jets issuing at an obtuse angle to each other. Each spray jet in this embodiment issues at an angle of 22.50 to the floor.

The frame 4 comprises a chassis part 22 and a handle 24. The chassis part has a pair of arms 26. Each arm 26 is connected at one end to the cleaning head about aligned pivots X, the arms being pivoted to respective plates 27 which are welded to the upper plate 8 of the cleaning head. The plates are carried towards the rear of the cleaning head, but forwardly of the wheel 14. At their other ends, the arms are connected together by two parallel cross pieces 28, 29, to which are secured the handle 24. Each arm 26 carries at an intermediate position a stub axle on which is mounted a large diameter wheel 30 having a pneumatic tyre. The tyre diameter is 25cm. The stub axles and the pivots x lie in a plane parallel to the floor.

The cleaning head wheels 12, 14 and the chassis part wheels 30 rotate about axes which are parallel to one another and parallel to pivots x.

With reference to Fig. 6, the main pneumatic line is shown in bold line and passed through a main isolator valve 32, a manifold block 34 and a stop valve 36. Three pilot lines are derived from the main line within the manifold block, one connected to a pressure gauge 38, one (40) being connected to a relay valve 42 and one (44) being connected to a manual control valve 46. When the control valve 46 is opened pilot line 44 is connected to a pilot line 48 which opens the stop valve 36 in the main pneumatic line, so allowing air supply to the motors, and acts upon relay valve 42 so that the valve member thereof adopts a position in which it connects input pilot line 40 to an output pilot line 50, whereby water supply valve 52 is opened.

To use the cleaning apparatus, control valve 46 is operated to simultaneously start the air motors and commence supply of water, as described in the previous paragraph. The apparatus is simply pushed, using handle 24, by an operative, over a grid to be cleaned. In this embodiment the heads may be rotated at any desired speed up to 800rpm. The pressure of the water jets is 10,000psi (67MPa) and the water supply rate is 15 gallons per minute (68 litres per minute). It has been found in experimental trials that several hours' accumulation of paint in a paint spray booth having a floor grid as described herein can be effectively removed, without chemical pre-treatment, even when the cleaning apparatus is pushed across the floor grid at a speed as fast as 30ft/minute.Should chemical pre-treatment as described in our co-pending application be carried out, effective cleaning can be achieved a lower pressure, the machine suitably being set so that the spray heads' rotation speed is at or towards the upper end of the range stated above, and the water pressure is lower. In this way effective cleaning can be achieved even with very rapid traverse times of the apparatus, and with little splashing and noise.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.

Claims

1. Apparatus for cleaning a floor, for example the floor grid of a paint spray booth, the apparatus comprising a cleaning head carrying a spraying means, the cleaning head having a pair of axles each of which carries at least one wheel for engaging the floor, one axle being located at or towards the front of the cleaning head and the other axle being located at or towards the rear of the cleaning head, the cleaning head being pivotally mounted on a frame about a pivot axis which is substantially parallel to the support axles.

2. Apparatus as claimed in Claim 1 wherein the cleaning head is pivotally mounted on the frame towards the rear of the cleaning head.

3. Apparatus as claimed in Claim 1 or 2, wherein the cleaning head is pivotally mounted on the frame at a position intermediate the axles (without necessarily being in the plane therebetween).

4. Apparatus as claimed in any preceding claim, wherein each axle of the cleaning head comprises a wheel whose circularly cylindrical floor-engaging surface is of a length (ie., dimension in the axial direction) which exceeds the spacing of the uppermost parts of a standard floor grid, whereby when the apparatus is passed over such a grid in a direction parallel to those uppermost parts, each such wheel will engage and run on at least one such part.

5. Apparatus as claimed in Claim 4, wherein the floor-engaging surface of each wheel is at least about 8cm in length.

6. Apparatus as claimed in any preceding claim, wherein the frame comprises two arms, the arms being connected to the cleaning head at or towards a respective transverse side thereof, the two connections defining the pivot axis of the cleaning head about the frame.

7. Apparatus as claimed in any preceding claim, wherein the frame has its own independent support axle, substantially parallel to the axles of the cleaning head.

8. Apparatus as claimed in Claim 7, wherein the support axle carries a wheel or wheels of large diameter relative to the wheels of the cleaning head.

9. Apparatus as claimed in Claim 7 or 8, wherein the support axle is constituted by two stub axles, carried by respective arms of the frame, and each carrying a wheel.

10. Apparatus as claimed of any Claims 7, 8 or 9 wherein, in use, the support axle of the frame and the pivot axis of the cleaning head about the frame lie in a plane substantially parallel to the floor.

11. Apparatus as claimed in any preceding claim, wherein the frame comprises a handle by means of which the apparatus can be pushed.

12. Apparatus as claimed in any preceding claim, wherein the cleaning head comprises a canopy beneath which is housed the spraying means, the canopy having downwardly extending side walls extending around its periphery to substantially retain, beneath the cleaning head, liquid sprayed from the spraying means.

13. Apparatus as claimed in any preceding claim, wherein the spraying means is such as to, in use, spray a liquid towards the floor being cleaned, at a small angle thereto.

14. Apparatus as claimed in Claim 13, wherein the angle is in the range 15-450.

15. Apparatus as claimed in Claim 14, wherein the angle is in the range 17-300.

16. Apparatus as claimed in any pre-eding claim, wherein the spraying means comprises a rotatable spray head.

17. Apparatus as claimed in Claim 16, wherein the spray head comprises one or more arms, and the end of the or each arm comprises a plurality of spray outlets arranged to supply non-parallel liquid jets.

18. Apparatus as claimed in Claim 17, wherein the end of the or each arm has two nozzles arranged to supply water jets at an obtuse angle to each other.

19. Apparatus as claimed in any of Claims 16 to 18, comprising a plurality of rotatable spray heads.

20. Apparatus as claimed in Claim 19, wherein two rotatable spray heads are employed, located side-by-side across the cleaning head.

21. Apparatus as claimed in any of Claims 16 to 20, wherein the or each spray head is rotated by means other than, or additional to, the propulsive effect of the liquid jets.

22. Apparatus as claimed in Claim 21, wherein the means for rotating the or each spray head, and the liquid supply for the apparatus, are commonly controlled by the user.

23. Apparatus as claimed in any of Claims 16 to 22, wherein the spray head rotation speed is about 200800rpm.

24. Apparatus as claimed in any preceding claim, wherein the pressure of the cleaning liquid is at least SOMPa.

25. Apparatus as claimed in any preceding claim, wherein the liquid supply rate is about 50-150 litres per minute.

26. Apparatus for cleaning a floor, for example, the floor grid of a paint spray booth, the apparatus comprising a wheeled unit comprising a cleaning head which carries a spraying means, the spraying means being such as to spray liquid, in use, towards a floor being cleaned, at an angle in the range 15-450.

27. Apparatus as claimed in Claim 26, and in any of Claims 1 to 25.

28. Apparatus substantially as hereinbefore described with reference to the accompanying drawings.