GB271097A - Improvements in and relating to apparatus for frosting glass - Google Patents

Abstract

271,097. British Thomson-Houston Co., Ltd., (Assignees of Pipkin, M.). May 12, 1926, [Convention date]. Void [Published under Sect. 91 of the Acts]. Etching-appuratus.-In apparatus for frosting by etching the inside surfaces of electric lamp bulbs and similar glass articles, a bulb 25 is supported over a pipe 24 extending upwardly from a vessel 20 containing strong etching-fluid, which is forced into the bulb by compressed air admitted bv a pipe 26, surplus fluid returning to the vessel through a funnel 28 and pipe 29. The fluid is kept at a suitable temperature by water circulated in a jacket 21. After being frosted, the bulb is washed out by supporting it over a water pipe 31, and the washed bulb is then subjected to a strengthening treatment consisting in applying weak etching-fluid by an apparatus 20<1>, 24<1>, 26<1>, 28<1>, 29' similar to that described above. Fig. 4 shows a modification whereby a number of bulbs may be treated simultaneously, the bulbs 25 being supported in holes in a table 40 having legs 39, which, at each station, rest on stops so arranged that the bulbs are over a series of nozzles 43, the table being raised and run along from one station to the next on rails 38. In a modified construction of the vessel 20, this is divided into two compartments by a horizontal partition, fresh etching-fluid being stored in the upper compartment and supplied, when required, through a hand-controlled valve to the lower compartment to maintain the fluid in use at a uniform strength.. Specification 254,316 is referred to.