CA2152851A1 - Lamp assembly, double wall, with insulator space between the walls - Google Patents

Abstract

A double wall lamp assembly adaptable to several types or configurations of small to medium size reading lamps, which basic designs and types of single wall construction have been in use for many years, however this invention has a very important difference in the design and construction details which offers inherent safety features not found in the lamps of the single wall basic designs and styles such as described herein. The very important differences are: [a] the double wall feature with adequate air space between the walls. [b] a double wall feature with porous or fibrous material between the walls {c} a drastic reduction in the heat transfer From the inner wall or body to the outer wall or body when the lamp is in use, thereby making the outer lamp body or wall safe for human contact. [d] a definite reduction in incidents of fire and/or burns due to carelessness.
The most common types of small to medium size lamps similar in configuration to the lamps covered by this patent are of single wall {body} construction and largely confined to desk types, wall types, goose neck types, pole types and bed headboard types, which, when used are usually in close proximity to the user.
These types normally use a 60 watt bulb, and when turned on for a considerable length of time, upwards of thirty minutes, will result in the lamp body getting very hot, upwards of 200 degrees Farenheit, and could cause a burn to the user when touched or handled in a careless manner, or if used improperly, could cause a fire. The regular or standard types of single wall lamps are usually made of sheet steel with baked on enamel surfaces or of plain or color dye-anodized aluminum.
However the outer wall or body of the double wall lamps covered by this patent can also be made of the same materials or could be made of a high density, dent proof, plastic material that can withstand a reasonable amount of heat and offer the desired safety features.
In the United States, one will discover that the types of small to medium size, single wall lamps referred to herein usually have a warning printed or stamped on the lower inside surface of the wall or body, which is probably a mandatory requirement, and reads as follows;
" CAUTION: TO REDUCE THE RISK OF FIRE USE 60 WATT OR
SMALLER TYPE OF LAMP."

Description

2152~1 The purpose of the double wall body is to provide an air space between the walls~or material such as neoprene sponge, polyurethane or other Fibrous material, which acts as an insulator so as to maintain an outer surface temperature safe enoush for human contact. The outer wall will have a relatively low conductivity coefficient while able to withstand thermal fatigue.
Some factors to be taken into consideration for the choice of material are weight, cost, ease of formation, machininy, availability, thermal conductivity, and durability.
The outer wall {or body~ effectively reduces the heat From a very hot condition of the inner wall to a very safe and reascnably warm condition oF the outer wall, which is a decided impro~ement over the standard single wall types in seneral use.
This invention is considered to be a new and workable idea oF ingenious quality, because these new features practically eliminates the inherent dangers oF the ordinary sinsle wall lamps similar in configuration to those described herein.
The air wall insulator, with permanently installed spacers allowins the free flow of air, is preFerred in these applications; however if a filler material is used between the walls, the material shall be lisht in weisht, not break down, disintegrate or emit any unusual odor or fumes after long and continued use.

- 2152~51 BACKGROUND OF THE IN~ENTION
The inventor purchased a bed headboard readin~ lamp in recent weeks and used it for the intended purpose for a short period. The lamp contained a 60 watt bulb and was turned on for approximately one hour and when he reached up to turn off the switch his hand accidentally touched the body or wall, o~ the lamp which was extremely hot, and he suffered an uncomfortable burn.
The inventor discovered during an extensive search amony lamp suppliers that the small to medium size lamps bein~ sold were of the single wall type which have been in use ~and sold}
for many years,and all have the inherent undesirable properties; these undesirable features have been effectively eradicated almost completely by this invention.
The inventor took steps to improve the quality and features of these particular types of lamps and he did this by the addition of an extra outer wall or body, with{a} an insulator air space and~b} a heat resistant porous material between the walls which reduced the heat and inherent dangers, and proved to be safe ~or human contact and thereby considerably reducing the danger of fire due to careless use.
Either method can be incorporated into the design of these lamps and still maintain the inherent safe properties.
An outer wall or body was made of a high density plastic as well as a sheet of metal {steel}, and both were considered satis~actory during the testing process.

It is believed that the double wall lamp, with air space or porous material insulator, covered by this patent, is an extremely safe type of low cost lamp, of the types described herein, that could be made available to the public. The air flow or air insulator is practically unobstructed and offers excellent safety features not found in the ordinary small to medium size lamps being sold or used currently. The material placed between the walls is also an effective method of reducing the heat considerably, to a safe temperature.
This invention is not intended to infrinye on any particular desiyn or configuration; an extensive search was made in these categories and no similarity was found. This double wall feature with insulator space, is adaptable to the regular styles and desi~n configurations of small to medium size reading lamps of the desk and wall types.
SUMMARY OF THE INVENTION
This double wall lamp body, with air space insulator, can be successfully adapted to many types and desiyns of small to medium size lamps which may or may not be in close proximaty to the user. The same can he stated for the material insert between the walls. It is considered tha a 3~3 inch space completely around and between the inner wall and the outer wall is most satisfactory for either method; i.e.-air space or material insert.
The configuration of the lamps may vary, and is not of yreat importance as this idea can be adapted to various types - 21~2~51 thereby makiny the article safe for human contact and reducing the incidence of fire due to carelessness. The double wall feature, with unimpeded air space between the walls, or if this space is filled completely with a porous or fibrous material is a notable and impressive improvement.
It should also be noted that the air space between the walls can be closed or partially closed around the lower edges while still maintaining a suitable air space insulator and still result in a safe product.
A safety open wire screen of the clip-on type may be attached to the outer circumference edge of the outer wall in order to further prevent human contact with the bulb, thus preventin~ damage to the skin and may be defined as an added safety feature.
The essence of this invention is to provide a safe and easily handled product that does not embody the inherent short-comings of the ordinary single wall small to medium size lamps of the types described herein, while not increasing the end cost by more than 20 to 25 percent, and still keeping the lamp within a "low cost" ran~e.
Limited tests were conducted on three lamp material and construction desiyns and the results are quite accurate within a range of plus or minus five de~rees Farenheit. All tests were conducted usiny a 60 watt lamp bulb.
A sin~le wall metal lamp was turned on and the heat on the surface on the outside of the wall or body was recorded;

- 21528Sl after 5 minutes the temperature rose to 90 degrees Farenheit;
after 15 minutes temperature rose to 1~0 degrees Farenheit.
after 30 minutes temperature rose to 205 degrees Farenheit.
Test was discontinued; heat was in the dangerous range.
The same lamp was used but was fitted with a sheet steel Cmetal} outer wall {or body} and a similar test was conducted, which allowed the free Flow of air; The results were as follows;
aFter 5 minutes temperature rose to 85 degrees F.
after 15 minutes temperature rose to 95 deyrees F.
after 30 minutes temperature rose to 105 degrees F.
Test satisfactory.
The same lamp was used but fitted with an outer wall {or body} of high density plastic and the test results were as follows;
after 5 minutes temperature rose to 90 degrees F.
after 15 minutes temperature rose to 85 degrees F.
after 30 minutes temperature rose to 98-100 deyrees F.
No notable increase was noticed after an additional 15 minutes oF testing. Results of test very satisfactory.
The same tests were conducted on the same lamps but the open space between the walls was Filled with {a} neoprene sponge and {b} open weave plastic, interwoven wire thread like material.
It should be noted that these tests were not conducted under very strict conditions or considered as accurate b 21528~1 engineering trials conducted by professional engineers, but were conducted by the inventor under stable conditions, using commercial types of sensitive thermometers and the inventor considers these tests to be fairly accurate within a reasonable tolerance range.

Referring now to the drawings, FIG. 1, FIG. 2, FIG. ~, and FIG. 5; these are some basic types of lamps showiny some detail of the double wall as seen in the lower edges of lamps in FIG. 1, FIG. 2, and FIG. ~. FIG. 3 is intended to show how the inner wall or body is covered by the outer wall or body which outer body is depicted by the dotted lines. Note also the inner bod~, 1, and the outer body, 2.
FIG. 6, is depicted to show the outer body, 3, which fits over the inner body, ~, shown asd FIG. 7, while FIG. G, and FIG. 9, shows the top view of the outer body, 5, and the inner body, 6, haviny air holes or open spaces which may differ in size and desiyn. FIG. 10, and FIG. 11, are depicted as cross sections. FIG. 12, shows the lower end of the double wall body with the outer wall, 9, extending longer than the inner wall body, 9, as shown in FIG. 13. FIG. 1~, is also another feature or type of wall closure with the outer wall material extendiny over the lower edge of the inner wall and having a series of holes or apertures, 7, in the lower folded over area to allow air flow; FIG.15 is a partial cross section. In all cases, the lower edges, where possible, are beaded over to prevent - 2~5~51 injury. One side Ot FIG. 15 shows how the space is filled with a plastic finerous material such as polyurethane wire or mesh or neoprene spon~e, 10.

Claims (9)

1. A metal lamp body having an outer wall or body, resulting in a double wall with air space between the walls of sufficient area to allow air flow to act as an insulator, resulting in the outer wall being safe for human contact.

2. A metal lamp body with a double wall, which walls are separated and held in rigid position by spacers or other means which allow air flow or air space to act as an insulator while effectively reducing the heat from the inner wall or body to the outer wall or body so as to maintain a surface temperature safe enough for human contact.

3. A lamp having an inner body of metal and an outer wall of metal or high density plastic, having a relatively low conductivity coefficient while able to withstand thermal fatigue.

4. A double wall lamp body with air space between the walls and completely open around the lower circumference and having air spaces or holes in the top surfaces of the inner and outer bodies so as to allow the free flow of air, which air flow will act as an insulator between the walls in order to make the surface of the outer lamp body or wall safe for human contact.

5. A double wall lamp body spaced between the walls with the lower ends covered or closed by having the material of the outer wall extending across the space between the walls over to the inner edge of the inner wall.

6. A double wall lamp body having the lower wall ends closed or covered by the extention of material of the outer wall to the inner edge of the inner wall and having a series of holes or apertures around the surface of the folded over material of the lower circumference so as to allow a free flow of air between the walls.

7. A double wall lamp having the features of claim 4, and claim 6, and the top surfaces of the inner body and the outer body having a series of holes or apertures to allow the free flow of air beween the walls.

8. A double wall lamp with air space between the walls that effectively reduces the heat transfer from the inner wall to the outer wall to suitable temperature range safe enough for human contact and reducing the incidence of fire due to carelessness, and where the temperature range is reduced by 50% or more by the effectiveness of the air insulator of the double wall.

9. A double wall lamp with satisfactory space between the inner wall {or body} and the outer wall {or body}, which space is fitted or filled with a substance such as neoprene sponge, plastic fiberous sheet or interwoven plastic coil; materials that can stand heat from 220 degrees to 240 degrees Farenheit without thermal fatigue, resulting in the outer wall {or body}

being cool enough, when lamp is turned on, to be safe for human contact.