GB2054420A

GB2054420A - Process and apparatus for brushing and polishing a surface

Info

Publication number: GB2054420A
Application number: GB7926044A
Authority: GB
Original assignee: TELLITS ELECTRICS Ltd
Current assignee: TELLITS ELECTRICS Ltd
Priority date: 1979-07-26
Filing date: 1979-07-26
Publication date: 1981-02-18
Also published as: GB2054420B

Abstract

A process and apparatus for brushing and polishing a substantially flat surface 2 such as a metal clock dial to provide thereon an overlapping pattern of substantially circular brush marks 14 comprises rotating a brush and the surface in opposite senses about parallel axes which are laterally offset. <IMAGE>

Description

SPECIFICATION Process and apparatus for brushing and polishing a surface Technical field of the invention The invention relates to process and apparatus for brushing and polishing a surface, such as the surface of a metal disc or dial to be used for the face of a clock, watch, metre or other instrument.

Background art Metal discs have often been brushed or polished by holding the disc on a plate and bringing a rotating polisher into contact with the surface, the axis of rotation being concentric with the centre of the disc.

In this way a concentric series of brush marks is obtained on the disc. However, it is difficult to obtain other than this non-circular array.

Disclosure of the invention It is an object of the invention to seek to provide a process and apparatus by which a non-concentric array of brush marks is obtainable.

According to one aspect of the invention there is provided a process for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising offering up the substrate to a brush such that the substrate and the brush are parallel and laterally offset, and rotating the substrate and brush in contact so that the surface is brushed to provide an overlapping pattern of brush marks.

According to a second aspect of the invention there is provided apparatus for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising a rotatable table for receiving the substrate, a rotatable brush head, a slide for mounting the brush head so that the axes of rotation of the brush head and table are laterally offset, means for reciprocating the brush head and table and means for counter-rotating the table and brush head.

Using the invention it is possible to produce on a flat surface a series of overlapping, circular, brushed lines all of which pass through the centre of a metal disc which is to be used as a clock face.

The advantages which may be obtained due to the invention consist particularly in the provision of process and apparatus which, in one apparatus, can provide a variety of overlapping brush marks which provide a pleasing aesthetic effect.

An embodiment of the invention is hereinafter described by way of example, with reference to the accompanying drawings.

Brief description of the drawings Figure I shows a plan view of a slide; Figure2 is a side elevation of Figure 1; and Figure 3 shows a plan view of a dial to be used as a clock face and brushed according to the invention.

Best mode for carrying out the invention Referring to the drawings Figures 1 and 2 show part of an apparatus 1 for brushing and polishing a substrate in the form of a metal disc 2 for use as a clock face. The apparatus 1 includes side columns, (not shown) which are connected by a first crosshead, (also not shown). There is a second, movable cross-head 3 which is parallel to the first one and which is receprocable vertically on the columns. On the underside of the second cross-head there are two spaced, parallel rails 4 and 5 which seat between them a slide 6. The slide 6 is secured to the cross-head 3 by bolts 7. The bolts 7 seat in elongate holes 8 in the slide 6, the length of the holes 8 determining the amount the slide 6 can move relative to the cross-head 3.

One side of the slide 3 has a series of depressions 9. The adjacent rail 5 has a plunger 10 mounted under the pressure of a spring 11 which urges the plunger 10 towards the slide 6. When the head of the plunger engages a depression 9 the slide 6 is secured in position. In order to alter the position of the slide 6, it is merely necessary to withdraw the plunger 10 away from the slide 6 by gripping hand knob 12 and pulling against the pressure of the spring 11. When the slide 6 is in the new position, the plunger 10 is released as that its head is urged by the spring 11 into engagement with another depression 9.

The arrangement is such that the slide 6 is never located with its central axis coincident with the central axis of the second cross-head 3.

The slide has a mounting for, on its underside, a motor 13 having an attachment for a rotatable brush 2, the axis of rotation being offset from the central axis of the second cross-head too, no matter where the slide 6 is positioned.

Located on the columns below the second crosshead is a vacuum table on which the substrate to be brushed and polished is mounted. The table is rotatable in a direction counter to that of the brush.

In operation, the slide 6 is set to a desired offset position and is held there by the plunger 10. A metal disc 2 to be brushed and polished is placed on the vacuum table and the disc and brush are rotated in opposite senses.

The table and second cross-head are then brought together, either by the cross-head moving, the table moving, or both the table and second cross-head moving towards each other, and the brush brushes and polishes the disc 2 until a desired overlapping pattern 14 of circular brush marks, as shown in Figure 3, is obtained.

1. A process for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising bringing the substrate and a brush together such that the substrate and the brush are parallel and laterally offset, and rotating the substrate and brush in contact in opposite senses so that the surface is brushed to provide an overlapping pattern of brush marks.

2. Apparatus for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising a rotatable table for receiving a substrate, a slide for mounting a brush head, means

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Process and apparatus for brushing and polishing a surface Technical field of the invention The invention relates to process and apparatus for brushing and polishing a surface, such as the surface of a metal disc or dial to be used for the face of a clock, watch, metre or other instrument. Background art Metal discs have often been brushed or polished by holding the disc on a plate and bringing a rotating polisher into contact with the surface, the axis of rotation being concentric with the centre of the disc. In this way a concentric series of brush marks is obtained on the disc. However, it is difficult to obtain other than this non-circular array. Disclosure of the invention It is an object of the invention to seek to provide a process and apparatus by which a non-concentric array of brush marks is obtainable. According to one aspect of the invention there is provided a process for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising offering up the substrate to a brush such that the substrate and the brush are parallel and laterally offset, and rotating the substrate and brush in contact so that the surface is brushed to provide an overlapping pattern of brush marks. According to a second aspect of the invention there is provided apparatus for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising a rotatable table for receiving the substrate, a rotatable brush head, a slide for mounting the brush head so that the axes of rotation of the brush head and table are laterally offset, means for reciprocating the brush head and table and means for counter-rotating the table and brush head. Using the invention it is possible to produce on a flat surface a series of overlapping, circular, brushed lines all of which pass through the centre of a metal disc which is to be used as a clock face. The advantages which may be obtained due to the invention consist particularly in the provision of process and apparatus which, in one apparatus, can provide a variety of overlapping brush marks which provide a pleasing aesthetic effect. An embodiment of the invention is hereinafter described by way of example, with reference to the accompanying drawings. Brief description of the drawings Figure I shows a plan view of a slide; Figure2 is a side elevation of Figure 1; and Figure 3 shows a plan view of a dial to be used as a clock face and brushed according to the invention. Best mode for carrying out the invention Referring to the drawings Figures 1 and 2 show part of an apparatus 1 for brushing and polishing a substrate in the form of a metal disc 2 for use as a clock face. The apparatus 1 includes side columns, (not shown) which are connected by a first crosshead, (also not shown). There is a second, movable cross-head 3 which is parallel to the first one and which is receprocable vertically on the columns. On the underside of the second cross-head there are two spaced, parallel rails 4 and 5 which seat between them a slide 6. The slide 6 is secured to the cross-head 3 by bolts 7. The bolts 7 seat in elongate holes 8 in the slide 6, the length of the holes 8 determining the amount the slide 6 can move relative to the cross-head 3. One side of the slide 3 has a series of depressions 9. The adjacent rail 5 has a plunger 10 mounted under the pressure of a spring 11 which urges the plunger 10 towards the slide 6. When the head of the plunger engages a depression 9 the slide 6 is secured in position. In order to alter the position of the slide 6, it is merely necessary to withdraw the plunger 10 away from the slide 6 by gripping hand knob 12 and pulling against the pressure of the spring 11. When the slide 6 is in the new position, the plunger 10 is released as that its head is urged by the spring 11 into engagement with another depression 9. The arrangement is such that the slide 6 is never located with its central axis coincident with the central axis of the second cross-head 3. The slide has a mounting for, on its underside, a motor 13 having an attachment for a rotatable brush 2, the axis of rotation being offset from the central axis of the second cross-head too, no matter where the slide 6 is positioned. Located on the columns below the second crosshead is a vacuum table on which the substrate to be brushed and polished is mounted. The table is rotatable in a direction counter to that of the brush. In operation, the slide 6 is set to a desired offset position and is held there by the plunger 10. A metal disc 2 to be brushed and polished is placed on the vacuum table and the disc and brush are rotated in opposite senses. The table and second cross-head are then brought together, either by the cross-head moving, the table moving, or both the table and second cross-head moving towards each other, and the brush brushes and polishes the disc 2 until a desired overlapping pattern 14 of circular brush marks, as shown in Figure 3, is obtained. CLAIMS

2. Apparatus for brushing and polishing a substantially flat surface of a substrate such as a clock dial, comprising a rotatable table for receiving a substrate, a slide for mounting a brush head, means for rotating the brush head contra to the rotation of the rotatable table, the axes of rotation of the rotatable table for the substrate and the rotatable means for the brush head being laterally offset, and means for relative reciprocable movement between the rotatable table and slide whereby in use the brush head and substrate can be brought into brushing contact.

3. Apparatus according to Claim 2, the table comprising a vacuum table.

4. Apparatus according to Claim 2 or Claim 3, the slide being mounted in rails supported by a crosshead and being adjustable relative to the cross-head.

5. Apparatus according to Claim 4, there being complementary guide means of the cross-head and slide for guiding the slide during adjustment.

6. Apparatus according to Claim 5, the complementary guide means comprising a bolt of the cross-head engaging in a slot of the slide.

7. Apparatus according to Claim 6, the slot being blind.

8. Apparatus according to any of Claims 5 to 7, including means to secure the slide in a desired adjusted position.

9. Apparatus according to Claim 8, the means comprising a series of notches in the slide and a plunger of the slide which is biassed towards the slide to engage in a notch.

10. A process according to Claim 1, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

11. Apparatus for brushing and polishing a substantially flat surface such as a clock dial, substantially as hereinbefore described with reference to and as shown in the accompanying drawings.

12. An article whenever polished using a process according to Claim 1 or Claim 10, or apparatus according to any of Claims 2 to 9 or 11.