USRE9512E - bobbins - Google Patents

Description

L.- S. ROBBINS, v Assignor to THE AMERICAN VULGANIZING W001) AN D LUMBER G0.

Preserving Wood.

No. 9,512. ReissuedDecjZl, I880.

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LOUIS s. ROBBINS, or NEW YORK, N. .,ASSIGNQR T rns AMERICAN y LoAmzmG-wooo AND LUMBER comm, or SAME prison.

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srncrrr'ca'rron forming part .1 Beissued we" Patent m. 9,512, dated December 21,1880. I Origins] No. 165.758, dated J uly 20, 1875. vApplication for reissue filed February 20. 1880.

To all whom it may concern Be it known that I, LOUIS S. ROBBINS, of the city and county of New York, in the State of New York, have inven ted a new an d-useful' 5 Improvement in Preserving Wood, of'which.

the following is a full, true, and exact description, reference being had to the accompanying drawing, making part of'thi's speciflcation.

In the usual processes hitherto employed in preserving wood the main object has been toi drive out of the wood its fluid matter or 'sap. Inkiln-drying, for instance, wood is placed in a chamber subjected to heat, and by a slow 15. process of distillation or evaporation the sap or fluid matter is expelled from the wood.

By this treatment the wood loses much of its life'and strength, the fiber is rendered brittle,

and the depleted pores readily absorb moisture; then the wood swells, and when the moisture is expelled the wood shrinks; and the wood thus treated continues swelling and shrinking alternately, according to'its exposure but the treatment of wood most approved and generally employed isthe slow process of desiccationby exposing it for some time in the open air, usually for several seasons, and

hence called seasoning. "The sap or fluid matter (which iu'its natural state is highly 0 hrs of the-atmosphere, and when thus diluted is more readily evaporated- ,f lhat much of the v fluid matter has been dissolved and expelled from wood which has been thus exposed for some time is shown by its loss in weightand measurement, and on .the outside it appears perfectly dry; but when the wood is subjected to the plane and the outside taken oil" and a soluble with water) is dissolved by the moistnew surface. presented,-the fresh fluid matter- 40 of preserving wood by injecting into the depleted pores foreign substances antiseptic in their nature, which will prevent fermentation and putrefaction by coagulating the albuminous elements of the sap. But in all these processes the machinery is complicated, the

material employed expensive, and when of 'a metallic nature, as is generally thecase, it

renders the wood brittle. By my process I do not drain the fluid matter or sap out of the wood, but retain and utilizeit in the wood, as the most natural and best filling for the pores or cells and cement for the fiber, and this is accomplished bythe use of heat and pressure.

' It is well known that the degree of heat necessary to create ebnllition in a liquid depends upon the amount-of" atmospheric or gaseous pressure upon its surface-the greater the pressure the higher the temperature required to reach the boiling-point. It is also well known that by heat chemical changes can be produced in nearly all substances. I have utilized this principle in my improved process, which consists in putting upon the wood an artificial pressure, atmospheric or gaseous, so as to prevent ebullition and consequent evap' oration of the fluid or liquid matter,whi1e at the same timethe wood issubjected to a temperature sufliciently high to effect a chemicalchange in the substances of which the sap is composed. By the increased pressure vaporization of the sap is-prevented, while the vaporizable melted products are diffused with .great uniformity throughout the-wood and are coagulated, solidified, .and fixed, and nce retained in the wood, filling the pores and-0e menting the fibers together, and the tendency fermentation and consequent decay is checked 'by the change or curing effect produced in them by the high heat.

In carrying out my process ot preparing wood any suitable apparatus may haemof the'vegetab'le juices and liquid mat 9o ployed; but I have shown in the drawing means that can be used.

' The chamber a is adapted 'to receive the wood, and it will be of a-size suitable to the material tobe operated upon. It is generally 5 bis connected tocoils of steam-pipes within the chamber a, so that the temperature of such chamber a; may be raised to any desired degree of heat. Hot water may take the place of steam, or heated air may be introduced;

10 Anair-pump, c, is employed to force air into WIJIIMVflGMNA-PIWe-gBgQd,

i and a thermometer, e, should also be provided.

The wood, having been placed'in the curing-.

chamber, is then subjected to heat and to a :5 pressure of air or gas forced 'into the chamber. The pressure may be raised to a point.

equal to one pound for each degree above 212 Fahrenheit, or thereabont, to which the temperature of the wood is raised; but it must be .20 raised to a pointsuflicieut to 'prevent the evaporation when the wood is heated to its highest point. By this means theevaporation of the juices-resinous and watery matters from the wood-is prevented, and the resinous matters 25 are also dispersed with cofisiderable uniformity throughout the wood, so as to fill up its pores. These. resinous matters are confined by the increased pressure, and solidify with g the wood and render it very dense. The vege- 30 table albumen is also solidified, and the result of the treatment is a very dry, uniform, and

, .hardlvood freeiromtsap..andlother matters that would hasten its destruction by fermentation. This heating operation tends to destroy. 3 5 insects and germsthat might destroy the wood or injure the same. This operation may propperature are gradually and simultaneously dc erly be termed vulcanizing wood. At the end of the operation the pressure and temcreased.

In subjecting wood to the combined action of heat and gaseous pressure, as befeaf*"eiplained, it is preferable to raise the tempers ture in the receiver till the vapors begin to distil--about 212 Fahrenheit-so as to expel the atmosphere from the pores, and then to set thepumpsatworlz-and inorease the-pressure in the receiver.

What I claim as my invention, and desire to secure by Letters Patent, is a 1. The within described process of vulcanizing or curing wood, which consists in subjectiug the wood, in a close receiver, to heat and an air or gaseous pressure greater than the pressure of the atmosphere, and sufliclent to prevent the volatilization of the liquid orv fluid matters at the temperature employed, whereby the said liquid or fluid matters are retained and coagulated in the wood, and the, wood cured and preserved, substantially as described. A

2. As a new product, vulcanized wood, as described, having the natural juices and sap coagulated and retained as solid and antiseptic substances filling the pores, the said wood being a solid, dense, and'uniform body, substantially as set forth.

Witnesses:

S. F. SULLIVAN,

- WM. A. PoLLoox,

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