According to the present invention there is provided a brush for cleaning the keys of keyboards or keypads, having a first set of bristles for brushing the tops of the keys, and a second set of bristles that are longer than the bristles of the first set for entering spaces between the keys to brush within those spaces during brushing of the tops of the keys by the bristles of the first set.

Although the bristles of both sets may be of pure, natural bristle in the sense of filaments of pig hair, it is to be understood that the term"bristle"is used herein in a general sense to refer without distinction to filaments of animal and man-made (for example, polyester) fibre.

The first and second sets of bristles may each comprises one or more rows of bristles retained in a head of the brush, and the one or more rows of each set may extend parallel to the one or more rows of the other set. One or more rows of the second set may be located to one or either side of the one or more rows of the first set.

Furthermore, the second set of bristles may be angled outwardly away from the bristles of the first set. More especially, the second set may be angled outwardly away from the bristles of the first set at an angle within the range 25-30 degrees, more specifically at an angle of substantially 30 degrees. Alternatively, the second set

of bristles may have the same orientation as those of the first set.

Three brushes in accordance with the present invention, for cleaning the keys of a computer keyboard or a keypad, will now be described, by way of example, with reference to the accompanying drawings, in which: Figures 1 to 3 are, respectively, a side elevation, a plan view from below, and a perspective view from one end, of a first of the three brushes according to the invention; Figures 4 to 6 are, respectively, a side elevation, a plan view from below, and a perspective view from one end, of the second brush according to the invention; and Figures 7 to 9 are, respectively, an end elevation, a plan view from below, and a side elevation of the third brush according to the invention.

Referring to Figures 1 to 3, the first brush has an elongate head 1 with integral handle-grip 2, formed, for example, of wood or moulded plastics. The head 1 has a bottom face 3 which is flat across its width but slightly bowed along its length, and which is inset with two sets of bristles. A first of the two sets comprises three rows of ten knots of bristles 4 that extend parallel to and closely alongside one another lengthwise of the head 1, whereas the second set comprises a single row of ten knots of bristles 5. The row of bristles 5 extends parallel to and closely alongside the rows of bristles 4, and the knots of both sets each fill tightly, and are securely retained within, individual holes in the face 3 of diameter between, for example, 0.12 and 0.16 inch (3 and 4 mm).

The bristles 4, which have a length for example of 0.875 inch (22 mm), are of a stiffness suitable for brushing the tops of the keys of a computer keyboard, for cleaning the keyboard. The bristles 5 have a similar stiffness, but are longer and are set or oriented in the head 1 angled outwardly from the rows of bristles 4. For example, the bristles 5 may have a length of 1.25 inch (32 mm) and be set to extend outwardly at an angle of about 30 degrees from the bristles 4 (the range of angle may be, for example, 25-35 degrees). The knots of bristles 4 are set in the head 1 to extend substantially normal to the face 3, so the knots of bristles 5 extend, for example, at some 60 degrees to that face and project beyond the bristles 4.

The brush is used for cleaning the tops of the keys of the computer keyboard one row at a time, and for this is held by the handle-grip 2 with the rows of bristles 4 aligned with and bearing on the tops of a respective row of the keys (it will be assumed in describing the use of the brush further that the keyboard concerned is of the standard QWERTY form and that it is held in the right hand). If, for example, the brush is held at the right- hand end of the keyboard with the bristles 4 on the tops of keys of the ASDFGH row of keys, the bristles 5 project across the QWERTY row into the space between the keys of the 12345 and QWERTY rows and bear on the lower flanks of keys of the 12345 row. By pressing the brush down and drawing it from right to left along the ASDFGH row, not only are the tops of the keys of that row brushed by the bristles 4, but the bristles 5 brush the lower flanks of the keys in the 12345 row and sweep detritus from the space between the 12345 and QWERTY rows.

By repetition of the operation, with the brush aligned with and drawn along the other rows of keys in turn, the tops of all the keys can be readily brushed by the

bristles 4. The bristles 5 will at the same time brush the lower flanks of all except the two lowermost rows of keys, and will sweep clear all except the space between them. The brushing of the lower flanks of these two rows and of the upper flanks of all keys, is however readily achieved, together with sweeping of the space between the two lowermost rows of keys, if the brush is pressed hard down during its passes along the rows of keys. When the brush is pressed down on a row of keys in this way, some bristles of the knots of bristles 4 in particular, splay out to brush the upper and lower flanks of the keys and project into the spaces between the rows above and below on the keyboard. The side flanks of the keys can then be cleaned with the bristles 4 and 5 by running the brush from top to bottom of the keyboard across the rows.

The second brush, to be described with reference to Figures 4 to 6, has sets of longer and shorter bristles, but there is no angling of the longer set of bristles.

Referring to Figures 4 to 6, the brush in this case has a head 11 with integral handle-grip 12 and a slightly-bowed bottom-face 13. The face 13 is inset longitudinally with two rows of ten knots of bristles 14 that are located between two parallel rows of ten knots of longer bristles 15. The bristles 14 and 15 are all set in the head 11 normal to the face 13 so that they have the same orientations as one another throughout the rows.

The brush of Figures 4 to 6 is used by drawing it along each row of keys of the keyboard, in turn. For each pass of the brush along the keyboard, the head 11 is held with the bristles 14 pressed down onto the tops of the keys and the two rows of bristles 15 straddling them. The bristles 15 accordingly, bear on the upper and lower flanks of the keys and sweep through the spaces between them and the immediately-neighbouring rows. In sweeping

through these spaces, the bristles 15 also brush the opposed flanks of the keys of those neighbouring rows.

The third brush, to be described with reference to Figures 7 to 9, has two sets of bristles with one set longer than, and angled between 25 and 35 degrees, specifically 30 degrees, to those of the other. In this respect, and referring to Figures 7 to 9, the third brush has an elongate head 21 that is integral with an aligned, elongate handle 22 and has a slightly-bowed bottom-face 23. The face 23, like the face 3 of the brush of Figures 1 to 3, is inset with three rows of ten knots of bristles 24 and with a single row of ten knots of longer bristles 25. The knots of bristles 24 are set normal to the face 23 whereas the knots of longer bristles 25 are set angled to it.

The brush of Figures 7 to 9 is used in essentially the same way as the brush of Figures 1 to 3, the longer and aligned handle 22 being preferred by some users.

Although the three brushes of Figures 1 to 9 are described above in the context of cleaning a computer keyboard, it will be apparent that they are equally applicable in the same way to the cleaning of other keyboards (for example of typewriters), and to the cleaning of keypads (for example of telephones and calculators).

Also, although the specific brushes described have ten knots of bristles in each row, more or fewer may be used according to the nature and size of the keyboard or keypad to be cleaned, or according to ease of use or, simply, preference. All (or only some) of the knots may be of natural bristle, but may instead be of a polyester.

Furthermore, although the knots are described above as being retained in holes in the face 3 of the head 1 (and

may be similarly retained in the heads 11 and 21) they may instead be stapled to it.

The bottom faces 3,13 and 23 of the brushes described, are slightly bowed along their lengths. This is believed to aid the brushing action, but the same effect can also be achieved by trimming the bristles. In this regard also, the brush of Figures 4 to 6 may be constructed from a brush having four rows of equal-length bristles simply by trimming the bristles of the two innermost rows.

Indeed, a modified form of the brush of Figures 4 to 6 may be provided in accordance with the invention by trimming down three of the rows, leaving just one with the longer bristles.