Spraying apparatus for coating glass sheet with metal oxide

摘要

A spraying apparatus for coating a hot and horizontally travelling glass sheet with a metal oxide coating film such as a heat-reflecting film by spraying an organometallic compound solution downwardly against the glass sheet. The apparatus comprises a spray gun movable over and transversely of the glass sheet, an outer enclosure and an inner hood, which has a middle portion defining therein a spraying zone and two end portions which are adjacent and upstream and downstream of the middle portion, respectively, and so shaped as to provide exhaust passages. The middle portion comprises two vertical guide plates arranged such that an ambient gas admitted through the space between the outer enclosure and the inner hood and an upper opening of the hood flows vertically downward into the spraying zone without unfavorably influencing the downward flow of the sprayed solution. The inlet to the exhaust passage in each end portion of the hood is so arranged as to smoothly exhaust the decomposition gas, residual portion of the sprayed solution and the admitted ambient gas from the spraying zone. In this apparatus, the metal oxide coating film can be formed with improved uniformity of its thickness and enhanced strength of adhesion to the glass sheet.