Improvements in Cool Safes and Cool Storage.
Year: 1895

page_text: Date of Application, 23rd Dec., 1895-Accepted, 25th Jan., 1896
COMPLEIE
DE CULTIVATION
Improvements in Cool Safes and Cool Storage.
I JAMES GODDARD LAMB of the City of Wellington in the Colony of New
Zealand Warehouseman do hereby declare the nature of this invention and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement :-
This invention consists in a practical application to cool safes and cool storage
of the well-known principle of reduction of temperature by evaporation.
I make a safe for storing food or produce of any sort which requires cool storage
as follows.
I make the inner walls of the safe of zinc or copper or other metal which is a
good conductor of heat or of any convenient combination of metals so as to form a
The
box with a doorway. On the top of this box I place a tank to carry water.
floor of this tank may form the upper side or roof of the safe and is by preference
made non-conducting to prevent the temperature of the tank and contents affecting
the chamber. On the outside of the zinc or other metal walls I place canvas so
that it is stretched continuously and closely against the whole surface of the metal.
I lead the water from the tank to this canvas by small tubes piercing the metal in
the upper portion and thus I saturate the canvas. The evaporation which follows
the exposure of water with so extended a surface robs the zinc or other metal of
heat and so cools the interior.
In order to secure a still more extended evaporating surface for the same body
of water I place on the canvas another sheet of woven material or webbing
possessing a projecting fibre such as Turkey towelling in close and continuous
contact with the canvas so as to absorb the moisture. I keep the pile of this
outwards and so greatly extend the evaporating surface. There is no leakage of
water from the outer walls of the safe as the canvas will retain the water except in
the matter of evaporation. The door-way roof and floor of my safe I make non-
conducting by the use of saw-dust charcoal or any insulating medium. A household
form of my safe is shown in the accompanying drawings in which
Fig. is a side view of the safe.
Fig. 2. shows a plan looking down on the top of the safe.
Fig. 3. is a sectional view of the safe.
a is the cool chamber formed (by preference) of four upright posts a¹ a¹ with a
bottom formed as an insulating chamber and a top or roof carrying a tank c with
cover c' to hold water and with its bottom insulated by any suitable non-conducting
substance. Three of the sides of this cooling chamber are formed of panels e. e
arranged to form evaporators the remaining side being occupied by a door or
slide. The evaporators e e consist in the first place of plates of zinc copper or
other suitable material 9 g which conduct the heat from the chamber a to a sheet
of stout canvas well stretched on the surface of the metal this canvas being
supplied with water or other suitable evaporating fluid from the tank c through the
pipes so as to soak the whole body of canvas. On this canvas again is
stretched Turkey towelling or other material i having a largely extended surface
loose in texture and having the pile outwards. These evaporating panels e e are
secured in place by frames k k and screws k¹ k².
I do not bind myself to the exact form of safe given above for it is obvious that
the sale may be varied in shape size or proportion and that the walls be
may
continued upwards and inwards so as to form part of the roof.
Instead of two

page_text: bodies of material outside of the zinc or other metal I use at times a single material
having a pile or other large surface. A large storage chamber may also be built
and my evaporating panels used for the walls and roof thereof. I use my panels
also for delivery or hawking carts for meat or produce. I also use my cool safe to
form a storage van for use on railways or roads. For this purpose I find it of
advantage to protect the evaporating surfaces from the direct rays of the sun and
from rain.
I do this by means of any preferred kind of roof and by the use of
louvres over the evaporators taking care to admit currents of air so as to increase
evaporation by the carrying away of the vapour from the evaporating surfaces.
I mount the safe on any preferred carriage or truck. When it is desired to support
the exterior of the evaporating panels and prevent sagging I apply straps of wood
or any metal to the exterior to sub-divide the panels or walls.
Having now particularly described and ascertained the nature of my inven
tion and in what manner the same is to be performed I declare that what I
.claim is :-
1. The combination to form a cool safe or store of a reservoir supplying liquid
to evaporating walls or panels such as described.
2. A cool safe or store having walls made of metal with canvas and material
with extended surface stretched on the exterior of the metal and supplied with
liquid to cool the metal by evaporation.
3. An evaporating panel for stores safes vans trucks or chambers consisting of a
quickly conducting metal plate with material on the outside to evaporate liquid
and cool the interior substantially as described herein and illustrated in the
accompanying drawings.
4. A safe or store or van with walls of evaporating panels supplied with liquid
through pipes from a tank on the top of the safe store or van as and for the
purposes substantially as described herein and illustrated in the accompanying
-drawings.
Dated this 30th day of October 1895.