GB2162772A - An apparatus for applying a linear decoration to ceramic articles of non-circular outline - Google Patents

Abstract

The apparatus includes an article holder (28) for rotating an article (32) about an axis (B) thereof and a tool carrier (48) guided for radial adjustment with respect to the article holder (28). An applicator head (80) supported on the tool carrier (48) by means of a rocker (70) pivotable about a horizontal pivot axis (D) carries a decorating tool (82) and is guided by guide rollers (86) at an edge (36) of the article (32). The decorating tool (82) is a brush next to which a spacer (84) is provided, which is pressed against the surface (38) to be decorated. The article holder (28) is pivotably adjustable about a horizontal axis (A) into a position in which the part of the surface touched by the brush (82) is horizontal and the tool carrier (48) is so constructed and arranged that in operation the brush (82) is maintained perpendicular to the surface, and the pivot axis (D) of the rocker is maintained parallel to a tangent to the edge of the article (32) in the area of the guide rollers (86). <IMAGE>

Description

SPECIFICATION An apparatus for applying a linear decoration to ceramic articles of non-circular outline This invention relates to an apparatus for applying a linear decoration to ceramic articles having a non-circular outline of the kind comprising an article holder supported so as to be driven in rotation for rotating an article about its axis, a tool carrier guided for radial adjustment with respect to the article holder, an applicator head mounted on the -tool carrier by means of a rocker mounted for piv otal rnoverneht about a horizontal pivot axis, the applicator head being provided with a decorating tool, and at least one guide roller located at an edge of the article, and biassing means for press ing the or each guide roller against the edge of the article and for pressing the decorating tool against a surface of the article which is to be decorated.

An apparatus of the kind set forth is shown in DE-A 2 713 489, in which the decorating tool is a roller supported on the applicator head so as to roll along the surface of the article to be decorated and wetted permanently with paint by means of a paint roller which plunges into a paint container.

The guide rollers, which roll along the edge of the article, are supported by an arm fixed to the appli cator head which is supported on a column for piv otal movement about a horizontal axis parallel to the axis of rotation the particle. The column is ad justable in parallel with and radially of the axis of rotation of the article by means of a cross slide as sembly. The applicator head is loaded by a coun terweight so as to press the guide rollers into contact with the edge of the article. The entire cross slide assembly is displaceable in parallel with the axis of rotation of the article by means of a pis ton and cylinder unit so as to press the decorating roller into contact with the surface of the article.

This known apparatus is cumbersome and thus not particularly well suited for applying fine lines of decoration.

It is an object of the invention to develop an ap paratus of the kind set forth such that the applica tor head will follow easily and almost without inertia the edge of the article to be decorated and the decorating tool will produce decorative lines of a uniformity attainable at present only by highly skilled manual labour.

According to our invention, in an apparatus of the kind set forth the decorating tool comprises a brush, adjacent to which is provided a spacer, which is pressed against the surface to be deco rated, the article holder is pivotably adjustable aböut ahiPi'oflbztal axis into a position in which the part of the surface touched by the decorating tool is substantially horizontal, and the tool carrier is constructed and arranged-such that in operation the brush is maintained substantially perpendicular to the surface, and the pivot axis of the rocker is maintained substantially parallel to a tangent to the edge of the article in the area of the guide roller or rollers.

Pivoting of the rocker, which may be a very light weight structure, permits the applicator head, supported by the spacer, to adapt almost without inert tia to the surface of the article even where this differs, to a greater or lesser degree, from rota- tional symmetry. The brush is pressed always in the same manner against the surface in question so that uniform decorative lines are produced. The decorative lines cannot run as the area of the article touched by the brush is in a substantially horizontal position.

Further features of the invention are specified in the subsidiary claims.

An embodiment of the invention will be described further below with reference to diagrammatic drawings, in which: Figure 1 is an elevation of an apparatus for applying linear decorations to a non-circular ceramic article, as seen in the direction of arrow I in Figure 2, without the article; Figure 2 is a vertical section along the line ll-ll of Figure 1, including the article; and Figure 3 shows a detail as seen in the direction of the arrow Ill of Figure 2, on an enlarged scale.

The apparatus is carried from a machine frame 10 by a horizontal arm 12. At its end the arm carries a clamping device 14 in which a pin 16 having a horizontal axis A is clamped. A bracket 18 is fixed to the pin.

The bracket 18 comprises a first prismatic guide means 20 on which a first carriage 22 is guided by rollers 24. The first carriage 22 is formed with a bearing 26 whose axis, hereinafter referred to as axis of rotation B, extends at right angles with respect to the first guide means 20 and to the axis A.

The bearing 26 supports an article holder 28 together with a template 30 removably secured to the same.

The article holder 28 holds an article 32, in the form of a substantially oval ceramic dish with a foot 34. The article 32 is held centrally in a conventional manner by vacuum, and has an oval outer edge 36, to the shape and position of which the template 30 is adjusted, and a surface 38 to be decorated the configuration of which differs greatly from a form of rotational symmetry with respect to the axis of rotation B, in accordance with the shape of the outer edge 36.

A second guide means 40 is provided on the first carriage 22 parallel to the first guide means 20 and it guides a second carriage 42 by means of rollers 44. A bearing 46 whose axis C extends parallel to the axis of rotation B is arranged on the second carriage 42. A tool carrier 48 is journalled for rotation in the bearing 46, and is guided for radial adjustment relative to the article holder 28 by the carriages 22, 42. The tOol .ctrreer- hás a pair of-roll-- ers 50 which are located one on each side of the axis C and in parallel with the same, and are adapted to roll along the edge of the template 30.

The tool carrier 48 also supports a rocker 70, which is mounted for pivotal movement about a pivot axis D by a base member 68. The pivot axis D extends in parallel with an imaginary straight line intersecting the axes of both rollers 50 at right angles. The rocker 70 has a substantially rod shaped cantilever 72 which extends at right angles with repsect to the pivot axis D and is guided for displacement relative to the base member 68 in a longitudinal direction. In the initial operating position shown in solid lines in Figure 1, this is parallel to the radial direction of adjustment of the tool carrier 48, so that the axis of the rod 70 intersects the axis of rotation B of the article holder 28 at right angles.The cantilever72 has an end member 74 facing the axis of rotation B, which is tiltable about an axis E upon loosening of a clamping engagement shown in Figure 3. An intermediate member 76 is attached to the end member 74 for universal pivot adjustment by means of a ball joint 75.

The intermediate member 76 includes a bearing 78 supporting a rotatable applicator head 80 to which are secured a decorating tool 82 in the form of a brush, a spacer 84, and a pair of guide rollers 86. The bearing 78 and the decorating tool 82 have å common axis, hereinafter referred to as brush axis F which is perpendicular to the surface 38. The bracket 18 is pivotally adjustable about the axis A so that the surface 38 is horizontal at its point of intersection with the brush axis F, so that the brush axis F itself is vertical. The spacer 84 and the guide rollers 86 are disposed at opposite sides of the brush axis F, with their axes in parallel with the same.

The decorating tool 82, the spacer 84 and the guide rollers 86 are adjustable sothat they can accommodate different articles. Thus the decorating tool 82 and the spacer 84 are axially adjustable, such that when the spacer touches the surface, the brush will draw a line. The two guide rollers 86 are adjustable radially so that the decorating tool 82 is kept at a desired spacing from the outer edge 36 of the article 32 when the guide rollers 86 roll along this edge. The spacing between axes of the two guide rollers 86 is small in comparison with the spacing between axes of the two rollers 50. It would also be possible to provided a single guide roller adpated to roll along the edge 36 of the article 32 instead of the two guide rollers 86.

The applicator head 80 is connected to the intermediate member 76 by two springs 88 which bias the applicator head to a central position unless the engagement of the guide rollers 86 with the outer edge of the article 32 forces it into another position. In operation engagement of the guide rollers 86 with the edge 36 is ensured by biassing means 90.In the embodiment shown this is a compression spring tending to displace the cantilever 72 radially toward the axis of rotation B of the article holder 28.

Abutment of the spacer 84 and thus also of the decorating tool 82 against the surface 38 to be decorated is ensured by biassing means 92. In the embodiment shown this is a tension spring acting between the tool carrier 48 and the base member 68. The- rocker 70 can be pivoted away from the article 32, against the action of the biassing means 92, by means of a lifting device 94 in the form of a piston and cylinder unit, in order that an article provided with a linear decoration may be replaced by a new one, without any obstruction.

The apparatus is driven by a shaft 52 mounted on the bracket 18, with its axis parallel to the axis of rotation B. The shaft is driven from a motor 56 by means of a belt drive 54 and carries a friction wheel 58 for engagement with the template 30.

The first carriage 22 is pulled upwardly by a-cable 60 which is loaded by a weight 62, whereby the template- 30 is held in abutment with the friction wheel 58. In a similar manner the -second carriage 42 is pulled upwardly by a cable 64 which- is loaded by a weight 66, whereby the rollers 50 are held in abutment with the template 30.

In operation, an article 32 is placed on the holder 28, and the bracket 18 is pivoted so that the part of the surface 38 which is to be decorated is substantially horizontal. The rocker 70 and the brush 82, spacer 84 and rollers 86 are then adjusted so that the brush 82 is at the correct place, and substantially perpendicular to the surface 38. The apparatus is therefore in the initial operating position shown in solid lines in Figures. Operation of the shaft 52 by the motor 56 rotates the template 30, and thus the holder and the article. As the article 32 rotates, the holder 28 and the first carriage 22 move on the first guide 20, as do the tool carrier 48 and the second carriage 42 on the second guide 40.The tool carrier 48 also rotates about axis C in order to maintain the pivot axis D of the rocker 70 subtantially parallel to a tangent to the edge of the article 37 at a point between the guide rollers 86.

The chain-dotted lines in Figure 1 illustrate the apparatus in one such operating position. The rocker 70 is of course also operative to maintain-the brush 82 in its substantially vertical position in contact with the surface 38. Once the decoration is complete, the rocker is moved away from the article by the piston and cylinder unit, so that the arti clean be removed, and another one placed in the holder 38. The rollers 86 taper towards their ends, and the stroke of the cantilever 72 is limited in such manner that the rollers 86 are free to return into their operating position, shown best in Figure 2, as soon as the new article 32 has been centred and is retained by the article holder 28.

Claims (6)

1. An apparatus for applying a linear decoration ceramic articles having a non-circular outline of the kind set forth, in which the decorating tool comprises a brush adjacent to which is provided a spacer, which is pressed against-the surface to be decorated, the article holder is pivotably adjustable about a horizontal axis into a position in which the part of the surface touched by the decorating tool is substantially horizontal and the tool carrier is constructed and arranged such that in operation the brush is maintained substantially perpendicular to the surface, and the pivot axis is maintained substantially parallel to a tangent to the edge of the article in the area of the guide roller or rollers.

2. The apparatus as claimed in claim 1,in which the rocker comprises a base member mounted on the tool carrier and a cantilever which is guided for displacement relative to the base member transversely of the pivot axis and in an initial operating position is substantially parallel with the radial direction of adjustment of the tool carrier, and the biassing means urge the cantilever towards the article independently of the tool carrier.

3. The apparatus as claimed in claim 2, in which the rocker further comprises an intermediate member which includes a bearing supporting the applicator head for rotation about a brush axis and is mounted at the cantilever for tilting adjustment about a tilting axis which is parallel to the pivot axis.

4. The apparatus as claimed in claim 3, in which at least one spring is disposed at the intermediate member to bias the applicator head to a central position within its range of pivotal movement about the applicator axis.

5. The apparatus as claimed in any preceding claim, in which two guide rollers are provided

6. An apparatus for applying a linear decoration to ceramic articles of non-circular outline of the kind set forth substantially as described herein with reference to and as illustrated in the accompanying drawings.