FR2817794A1 - MECHANICAL PRESS FOR THE PRODUCTION OF TILES - Google Patents

Abstract

Mechanical press for the production of tiles in which the central cam (3) of the camshaft (1) which controls the return stroke of the compressor acts on it, by means of a balance (11) to which is operationally associated a pushing device. The pushing device consists of a high pressure hydro-pneumatic cylinder (10).

Description

The present invention generally refers to presses for the

production of tiles.

  More particularly, the invention relates to a mechanical press for the production of tiles of the type comprising a support structure carrying a lower mold carrier group and a compressor carrying upper molds, the compressor being actuated by a rotary camshaft comprising two cams lateral for the operating stroke and a central cam for the return stroke of the compressor. In mechanical presses of the above type, produced for a long time and successfully marketed by the Applicant, the central cam acts on the compressor through a pendulum supported in contact with a bearing against said central cam by the action of a pushing device. The function of this balance wheel with the corresponding pushing device is to compensate for possible timing errors between the central cam and the two side cams, as well as possible dimensional errors, in order to constantly maintain contact between the camshaft. and the compressor in any

operational condition.

  In presses of this type known to date, the pushing device uses a series of packs of bucket springs which support the balance against the central cam with a very high elastic pre-tension. This solution has a serious drawback: in the event of the rupture of one or more bucket springs in the series of packages, the pushing device is exposed to the risk of seizure, the consequence of which is the application to the balance of a variable load, or in any case not in conformity with that projected, with the consequent risk of applying excessive stresses liable to cause early wear and in any case non-optimal functioning of the

hurry.

  The object of the present invention is to remedy this drawback. According to the invention, this objective is achieved thanks to the fact that said thrust device consists of a hydro-pneumatic cylinder with high

pressure.

  Thanks to this idea of solution, we eliminate the use of traditional bucket springs, ensuring for the entire operational life of the press, the consistency of the load applied between the balance and the central cam of the camshaft , in order to eliminate the drawbacks described above. The invention will now be described in detail with reference to the attached diagrams, provided by way of non-limiting example, in which: FIG. 1 is a schematic view in vertical section showing the part of a mechanical press for the production of tiles according to the invention corresponding to the camshaft for actuating the compressor; Figure 2 is a cross-sectional view along line II-II of Figure 1, and Figure 3 is a cross-sectional view along the line

III-III of figure 2.

  For simplicity of illustration, the attached diagrams represent only the portion of a mechanical press for the production of tiles which strictly respects the present invention. On the other hand, the general shape of the press is completely conventional and therefore well known to those skilled in the art. It should however be explained briefly that the press consists of a support structure comprising two sides connected by a base and by a lintel. In the lower area of the support structure, a rotating lower mold carrier group, normally consisting of a six-sided drum, rotates between the sides of the support structure actuated by a cross star

from Malta.

  A compressor carrying the upper molds is controlled synchronously with the rotation of the drum, as explained below, to compress a loaf of clay or a cake situated between the

lower and upper molds.

  For the actuation of the compressor, there is provided a rotary camshaft 1 comprising, typically in one piece, two lateral cams 2 between which there is a central cam 3. The two lateral cams 2 control the operating stroke of the compressor, while that the central cam 3 controls the return stroke through a balance 11 oscillating around an axis 4 parallel to

the camshaft 1.

  The balance 11 has a lower arm 5 which rotatably supports, by means of rolling bearings 6, a rotary roller 7 disposed in contact with a bearing with the surface of the central cam 3. The other arm of the balance 11, indicated by 8, is articulated at 9 to a pushing device generally indicated by 10, which constitutes

  the specific object of the present invention.

  The function of the balance 11 with the pushing device 10 between the central cam 3 and the press compressor has the function of compensating for possible timing errors between the side cams 2 and the central cam 3, as well as possible dimensional errors, ensuring constant contact between the camshaft 1 as a whole

and the compressor.

  In accordance with the invention, the pushing device 10 consists of a hydro-pneumatic high pressure cylinder, which eliminates the use of bucket springs or similar elastic systems, with the corresponding drawbacks. For example, the pre-tension pressure of the hydro-pneumatic cylinder 10 could be

Around 100 bars.

  Of course, the above description has only been given

  non-limiting example and various modifications may be made

  by those skilled in the art without departing from the scope of the invention.

Claims (1)

CLAIM   1. Mechanical press for the production of tiles, comprising a support structure carrying a lower mold carrier group and a compressor carrying upper molds, said compressor being actuated by a rotary camshaft (1) comprising two lateral cams (2) for the operating stroke, and a central cam (3) for the return stroke of the compressor, and in which the central cam (3) acts on the compressor through a balance (11) pressed in contact with a bearing with said central cam (3) by the action of a pushing device (10), characterized in that said pushing device consists of a high pressure hydro-pneumatic cylinder (10).