The invention relates to a spray head for a spraying tool, especially for spraying mold halves in a pressure casting machine. The spraying tool has spray nozzles fed with spraying agents and is fixed upon spray plates or spray bars which are assembled in a modular manner.
A spray head of this kind is disclosed in U.S. Pat. No. 4,760,961. The elements therein, equipped with spray nozzles, are assembled together column-wise in vertical or horizontal lines, and the media to be sprayed can be passed from element to element. These individual spray elements and also spacing parts inserted between them are held together by threaded bolts which are passed through openings in the elements. This method has the disadvantage that, for different sizes of the assembled spray elements or plates, different fasteners of various length have to be prepared. It is also disadvantageous that, in the case of a plurality of module-like elements arranged in a row, the threaded bolts or tie bolts have to be released and with them all the extensions that they hold together. Under certain circumstances, if an additional extension or reduction of elements not threaded on at the end is needed, but at the beginning, i.e., close to the distribution bar, all of the elements have to be taken off from the tie bolt. In this case dirt can enter at the points of separation.
EP 0 724 486 B1 discloses a spray bar on which plate-like elements are assembled. There too, however, the component parts are held together by threaded bolts or tie bolts of appropriate length.
An object of the invention is to design a spray bar such that a simple modular assembling of individual spray elements or connecting parts is possible without the need for fastening the parts together with threaded bolts or the like.
To achieve this and other objects, a spray head has coupling elements. The coupling elements have passages for the media to be sprayed, such as air, control means and spray media, are provided on the ends of the parts to be joined together, and are connected to the channels supplying the media. The coupling elements reach into the two chambers of the ends to be joined and are provided with hollow spaces with at least one sloping plane, which are engaged by clamping means which can be operated from the outside and force the parts tightly against one another.
By this configuration each element is provided on its connecting surfaces with connecting means which permit the elements to be released at any point, without the need to thread bolts or the like through holes.
In an advantageous configuration of the invention the coupling elements are provided at both face ends with sealing rings, so that they also provide the necessary seal between two elements which are to be assembled together.
The coupling elements can be made simply as cylindrical pins having two recesses each. The recesses are provided with planes sloping up toward one face surface. In this case the clamping means can be configured simply as screws with a conical tip which cooperate with the recesses.
In further development of the invention, pairs of chambers can be provided parallel to one another at each end of the component elements, and these chambers can be coaxial with the passages carrying control air and parting agents. Also at least one passage can be provided for drying air or compressed air between the passages provided for control air and parting agents.
The component elements can be provided with angled end portions for the connection of additional component elements or plates at an angle, and the end portions of attached corner pieces are formed in a simple configuration with angles of any kind, e.g., 45° or 90°. With this configuration there is also the possibility that component elements can be provided, for example, in bar or plate form turned away from one another at different directions and angles. Thus any desired spatial arrangement of spray elements is possible. To lengthen or shorten the spray bars or spray plates it is necessary only to separate them at the point at which the lengthening or shortening is to be made. All of the coupling elements in the entire spray head are in that case identical.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.