GB2124568A

GB2124568A - Removing fluent material

Info

Publication number: GB2124568A
Application number: GB08320900A
Authority: GB
Inventors: Andrew Harry Thomas
Original assignee: Individual
Current assignee: Individual
Priority date: 1982-08-03
Filing date: 1983-08-03
Publication date: 1984-02-22
Also published as: GB8320900D0

Abstract

A device 1 for removing fluent material from a moving wheel 3 comprises a roller 4 rotatable by the wheel 2 and means 5 for retaining the roller 4 against the wheel 3. When rotating the roller 4 takes the fluent material off the wheel 3 and throws it off tangentially, away from the wheel. The device may be used for any wheel for example the wheels of cycles, particularly light-weight racing cycles, instead of mudguards. This decreases both the wind resistance against the cycle in use and the actual weight of the cycle. <IMAGE>

Description

SPECIFICATION Removing fluent material This invention relates to methods and devices for removing fluent material from hard surfaces, for example from wheels of cycles or wheels or machines used in factories.

Conventionally, one way of dealing with spray from the rim of a wheel moving through a fluent material is to have a supported guard member disposed around the wheel rim, whereby spray from the wheel moving past the guard is shielded.

Throughout this specification and the claims, the term "rim" means the outer perimeter portion of a wheel and includes the rolling surface of wheels both with and without tyres.

Such guards are employed for example as "mudguards" for cycles. Especially in the case of racking cycles, mudguards increase the wind resistance, they add weight to the cycle and they spoil the general appearance of the cycle.

Accordingly, it is an object of this invention to overcome such disadvantages.

It is also an object of this invention to be able to remove fluent material, in particular liquid, effectively from a surface moving relatively to the fluent material.

According to a first aspect of the invention, I propose a device for removing fluent material from the surface of a solid, the device comprising a roller freely mounted for rotation about its axis of symmetry and disposable in contact with the solid surface, wherein the surface of the roller contactable with the solid surface has not means of meshing with the solid surface.

According to a second aspect of the invention, I propose a method of removing fluent material from the surface of a solid, comprising disposing a freely mounted roller in contact with the surface and rotating the roller relatively to the surface such that fluent material is picked up by the roller and thrown off the roller tangentially.

This device can be employed with a wheel of any size and application. One of the surface and the wheel need not be movable. The roller can be driven or not. The smaller the roller with respect to the wheel, the better is the take-off effect. An advantageous ratio of the diameter of the wheel to the diameter of the roller is 100:1 and typically the roller would be appoximately 1 cm in diameter.

Fluent material can be effectively removed from surfaces such as the rims of wheels using the device of this invention.

Considering a moving wheel and a roller, movable either by the wheel or other means, according to this invention, the peripheral speed of both the roller and the wheel is equal, assuming no slip between the roller and wheel.

The force required to retain fluent material, e.g.

a liquid droplet on the rim of the wheel is F,

where m is the mass of the material V is the linear velocity and r is the radius of the wheel or roller.

If the wheel has radius R1 and the roller has radius R2, the forces needed to retain the material on the respective surfaces are F, and F2 and

Thus, for a wheel of 66 cm diameter and a roller of 1 cm diameter, F2=66 F1. For a stationary wheel, clearly F2 is proportional to the linear velocity of the roller and inversely proportional to the radius of the roller. This has the effect that fluent material picked up by the roller is immediately thrown off tangentially. The only force available to retain the fluent material is surface tension which is usually substantially the same on both the roller and the wheel. The roller surface is substantially free of liquid by the time it revolves to come into contact with the wheel again.

The surface of the roller can be rought or of a material more hydrophilic than the wheel material. This causes the roller to pick up substantially all the fluent material from the wheel rim and the fluent material is then ejected.

The roller may be cylindrical and the center of the roller 1 may merely contact the wheel, as shown in Figure 1. The rotational speed of the wheel is usually sufficient to cause the fluent material to migrate to the center of the wheel rim, as shown in Figure 2.

The preferred form of roller 1' has concave sides, as shown in Figure 2. This has the advantage that the area of contact between the wheel 2' and roller 1 ' is significantly increased and the roller is self-centering. Also, the movement of fluent material from the wheel to the roller and then off tangentially is assisted by the concavity. At the center of the roller a) the linear velocity of the roller is equal to that of the wheel and towards the roller sides b) the linear velocity is much greater resulting in greater forces because the radius of the roller increases towards the sides of the roller. The greater forces improve the deflection of the fluent material by the roller.

Furthermore the sharp edges of the roller facilitate the formation of droplets and hence, the ejection of the fluent material.

There is minimal energy loss as there is virtually zero friction at the point of contact between the roller and the surface. Hence, the roller is highly durable. Moreover, the wear on the surface e.g. a tyre is minimal. There is no requirement for the parts of the device to be particularly strong since the reaction forces are minimal in view of minimal applied forces. The roller can, for instance, be made of a hard plastics or hard rubberised material.

Furthermore, the device can be made extremely light-weight and this is advantageous for racing cycles for example, the weight of which is cirtically important. The device can be typically less than a tenth of the weight of a conventional mudguard.

The roller of the device of this invention is easy to clean and replace. the device is also inexpensive to manufacture.

A guide member such as a flap may be used in order to direct the removed fluent material in any desired direction, for example towards the ground and away from people's faces.

The retaining means may be biassed against the wheel rim by any suitable means, for instance a tension spring or a counterbalancing weight.

Embodiments of this invention are described by way of example and with reference to the drawings, in which: Figure 1, is a cross-section of a first roller according to the invention adjacent a wheel rim; Figure 2 is a cross-section of a second roller according to the invention adjacent a wheel rim; Figure 3 is a partial diagrammatic side view of a wheel employing a device as shown in Figure 1; Figure 4 is a diagrammatic view of a wheel with a device as shown in Figure 1; and Figure 5 shows a bicycle with devices according to this invention one mounted for use on each of the front and the rear wheels of the bicycle; Figure 6 shows an alternative roller retaining frame; and Figure 7 is a plan view of the alternative roller retaining frame of Figure 6.

A device 1 a for removing fluent material, particularly liquid, from the rim 2a oF a moving wheel 3 has a roller 4 of small diameter compared with the diameter of the wheel. The roller 4 is mounted on a retaining frame 5 comprising a pair of parallel arms 6 which are connected with an elongate support 7. This support member is attached to the bicycle frame near the hub (not shown) of the wheel 3.

The roller 4 is held against the rim of the wheel in use by means of a tension spring 8 connected between the retaining frame 5 and the elongate member 7. The longitudinal, rotational axis of the roller is aligned parallel to the rotational axis of the wheel.

When the wheel is moving for example over the surface of or through fluent material, or over a hard surface carrying fluent material, fluent material is picked up on the wheel rim, the fluent material may be water and solid matter such as dirt. The body from which fluent material is picked up may be moving or not.

The roller 4 is rotated by the angular movement of the wheel 3 and when the fluent material on the wheel meets the moving roller it is picked up by the roller from the wheel rim 2a away from the wheel 3 in the direction of rotation of the roller 4 and thrown tangentially from the roller outwardly from the wheel, as a result of centripetal force due to the rotation of the roller and due to lack of surface tension as discussed earlier. Some solid matter may also be included and deflected in the same direction and some may collect on the roller 4. The roller 4 can be easily cleaned after use.

The flap 9 is attahced to the retaining frame 5, as shown in Figure 3, and this deflects the takenoff liquid downwardly. This is particularly useful if for example a person would otherwise be in the way of the taken-off liquid.

The wheel tends to stay drier using this device rather than a guard because fluent material often falls back onto the wheel from the confronting surface of the guard whereas in this invention most of the fluent material is deflected away from the wheel by the roller 4.

An alternative roller retaining frame 5' as shown in Figures 6 and 7, supports the roller 4' and houses and biasses a spring 8' against the roller 4' in order to hold it against wheel rim 2a'.

Elongate support members 7', similar to those 7, are attached to the bicycle frame near the hub.

As mentioned earlier, the roller in either of the above embodiments need not be cylindrical and may alternatively be concave, as shown in Figure 2.

Devices according to the invention may be used for any wheels for example the wheels of cycles, particularly light-weight racing cycles, instead of mudguards. This decreases both the wind resistance against the cycle in use and the actual weight of the cycle.

Claims

1. A device for removing fluent material from the surface of a solid, the device comprising a roller freely mounted for rotation about its axis of symmetry and disposable in contact with the solid surface, wherein the surface of the roller contactable with the solid surface has no means of meshing with the solid surface.

2. A device according to claim 1, wherein the solid comprises a rotatable surface of revolution.

3. A device according to claim 2, wherein the rotatable surface of revolution is a wheel.

4. A device according to claim 3; wherein the roller is angularly movable solely by the angular movement of the wheel.

5. A device according to any one of claims 1 to 4, wherein the surface of the roller contactable with the solids surface is concave.

6. A device according to claim 5, wherein the contactable roller surface is rough or comprises a material more hydrophilic than the wheel material.

7. A device according to any one of claims 1 to 6, including a retaining frame, connected with a pin located through a longitudinal axis of the roller, and means for biassing the roller against the wheel rim.

8. A device according to claim 7, wherein the biassing means comprises a spring connected between the retaining frame and a support member.

9. A device according to claim 8, wherein the support is elongate and has one end fixed near the hub of the wheel.

1 0. A device according to any preceding claim having a guide for deflecting fluent material thrown off the roller.

11. A device according to any preceding claim, wherein the roller is made from hard plastics or hard rubberised material.

12. A device according to any one of claims 3 to 11, wherein the ratio of the diameter of the wheel to the diameter of the roller is approximately 100:1.

13. A device according to claim 12, wherein the diameter of the roller is approximately 1 cm.

14. A method of removing fluent material from the surface of a solid, comprising disposing a freely mounted roller in contact with the surface and rotating the roller relatively to the surface such that fluent material is picked up by the roller and thrown off the roller tangentially.

1 5. A method according to claim 14, wherein the roller is moved solely upon angular movement of the solid which is in the form of a wheel.

1 6. A method according to claim 15, wherein the roller is biassed against the wheel.

17. A method according to claim 14, 1 5 or 16, including further deflecting the fluent material thrown off the roller.

18. A device for removing fluent material from the surface of a solid, constructed and arranged substantially as herein described, with reference to any of the drawings.

1 9. A method of removing fluent material from the surface of a solid, substantially as herein described.