DE805509C - Protective bell for electric miner's lamps - Google Patents

Description

The production of protective bells from multilayer glass is insofar difficult than with the intermediate layer, which is filled in liquid or pulpy form becomes, irregularities in the wall thickness cannot be avoided. This Disadvantage is eliminated by the invention described below. It becomes through this a synthetic resin bell used as an intermediate layer, the outer bell a and the inner bell b and the intermediate bell c made of synthetic resin conically shaped upwards so that a nesting of the three (makes it possible to lure without difficulty and the connection to one another is established when the temperature is appropriate.

It is known that the bells are matted to avoid glare by etching or sandblasting as well as hot multilayer glass bells by clouding the Apply intermediate layer. The former type has the disadvantage that it only works on the outer or inner surface of the simple protective bells can be applied, so that dust and dirt adhere very easily and impair light transmission. In the case of multilayer glass bells, the intermediate layer of which is clouded, to reduce the glare unevenness in thickness is unavoidable, so that (read light is distributed unevenly.

According to the invention, to reduce the twist on the inside the outer bell jar a or on the outside of the inner bell jar b an opaque one Paint layer applied. After assembling the two glass bells a and b with the synthetic resin bell c and its heating for the purpose of connecting the three Bells with each other can no longer pollute and also no more uneven clouding appear. It is unavoidable when the glass bells are made in pressed glass. (let the thickness of the glass wall, especially the dome, be different. If you were to provide the two glass bells with sealing edges, so can the case occur that if the dome of the outer bell jar a is too strong, the edge the inner bell b is not in contact and flakes off when the sealing ring is pressed against it. It is therefore only the outer glass bellea with a sealing edge according to the invention d provided. In order to prevent the intermediate bell from shattering the bell jar c is pressed inwards made of synthetic resin or similar material, this is conveniently pulled with under the sealing edge d of the outer bell jar a, so that both bell edges form a common sealing edge.

Claims (4)

PATE \ T.a \ SPRCCIIE: i. Protective bell for electric mine lights made of multilayer glass, characterized in that it consists of an outer bell jar (a) and an inner (b), also made of glass, of the same or different wall thickness, and an intermediate bell (c) composed of synthetic resin or the like and the bells are tapered towards the dome. 2, protective bell according to claim i, characterized in that the outside of the inner bell jar (b) or the Inside of the outer bell jar (a) with a Triibschicht, z. B. paint provided is which diffuses light. 3. Protection bell according to claim i and 2, characterized characterized in that the outer bell jar (a) has a sealing edge (d) (Fig. i). 4. Protective bell according to claim i to 3, characterized in that a sealing edge (e) of the synthetic resin bell (c) rests on the sealing edge (d) of the outer bell jar (a) (Fig. 2).