US2087965A

US2087965A - Method for treating wood

Info

Publication number: US2087965A
Application number: US3926A
Authority: US
Inventors: Frank W Cherrington
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-01-29
Filing date: 1935-01-29
Publication date: 1937-07-27
Anticipated expiration: 1954-07-27

Description

y 1937. F. w. CHERRINGTON 2,087,965

METHOD FOR TREATING WOOD Filed Jan. 29, 1955 Patented July 27, 1937 umice mm FATEN'E" 4 Claims.

This invention relates to a method for treatingwood, and is more particularly directed to the treatment ,of timbers, logs, ties, or similar large bodies of wood with a preservative such 51 as creosote oil, paraffin, or the: like, or with a fireproofing solution, containing, for example, sodium acetate.

Ithas'heretoiore been considered that a preservative treatment could be efiectively administeredto wood only after the wood had been thoroug hly dried to remove as -much of the moisturecontent as possible. For this reason, it has been the practice to store large quantities of the green lumber to await natural drying and then .to treat-the lumber by forcing the preserving liquid'into the grain by hydraulic pressure. The success of, this method has bee n variable, .since the'penetrationof the preservative varies with the kind of wood under treatment, and the degree of .drying previously imparted thereto. .If is, method cannot be successfully employed -with green wood as it is practically impossible to force preserving liquid intoa green body of wood to: a;-d ep-th which would satisfy even the most len; nt commercial requirements.

has now been-found that it is possible to obtain a complete penetration, of the preservative while flthewood is in its green, wet condition, and that this may be accomplished in a very short time providing the penetrating force is exerted lengthwise of the log, as by centrifugal i action.

The primary object of the present invention is the provision of a novel method for introducing preserving liquid into green wood.

Another object of the invention is the provision of such a method which includes the introduction of preserving liquid lengthwise oi the log or wood body, while the wood is in its green or undried state.

Another object of the invention is the provision of a simple and ef'ncient apparatus to carry out my method of treating wood.

Other objectsand advantages of the invention will become apparent as the description proceeds, reference being had to the accompanying drawing, in which an apparatus is disclosed which illustrates the principles of the invention, and in which- Figure 1 is a fragmentary side view of an apparatus suitable for my method; Fig. 2 is a plan View with parts in section, taken on line 2-2 in Fig. 1; Fig. 3 is a perspective detailed view of a retaining key; Fig. 4 is a perspective view of a suitable receptacle for the wood to be (Cl. in -2i) treated; Fig. 5 is a fragmentary section on. line 55 in Fig. 4; Fig. 6 is a detailed View of a suitable closure for the wood receptacle, and Fig. 7 is a fragmentary section at in Fig. 4.

Referring to the drawing, one form of the apparatus which may be mod to carry out my method, particularly as applied to railway ties, includes a rotatable table member l mounted on a central standard 2 andbraced in itsrotary movements by wheels i adapted to run on a circular track 5.. The track may be carried by any suitable means such as a concrete bed. 6. The entire machine is preferably disposed in a pit, or otherwise suitably protected around its periphery.

A gear I is carried by the rotatable table member l and is in mesh with a pinion 8 driven by a suitable motor 9, which is mounted on the sta tionary central standard 72, and is thus adapted to rotate the table [1. 20

As will be seen in Figs. 4 and 7, I prefer to encase each tie A, or piece or wood, to be treated in a suitable. receptacle such as a rectangular metallic member it having its inner end open while the wood is being placed therein, and its outer end inturned to form sharp edges it? which engage the wood, and in use form a seal therewith. The outer end is entirely open except for the space required to form the inturned edges for a purpose which will presently become apparent. Thus, the wood is entirely encased except at the outer end. At its inner end. each receptacle is provided with means to attach to a centrally disposed hub l8, which means may include slots M each adapted for the reception of one side of an H-shaped retaining key l5 shown in Fig. 3. The other, similar half. of the retaining key is adapted to be fitted into a slot 55 formed in the hub it carried by the rotary table. The hub It may have any number of sides, each of which is adapted to carry one of the tie receptacles. The hub is provided with a central preservative dispensing conduit 29 from which branch pipes '22 project, one for each of the receptacles. A flexible coupling it extends from each branch conduit and, in use, connects to a stub pipe 26 carried adjacent the inner end of each receptacle and behind the innermost portion of the tie to be treated. Suitable valves 23 control the flow of preserving liquid in each branch while a main valve Sill controls the flow in the dispensing conduit 2b.

In treating ties according to my method, each tie is placed in a receptacle i8, and a backing plate 32 slid into the receptacle after the tie to close oif the inner end. Thus, the ties are each entirely surrounded except for one end. The receptacles are then placed on the table I with their inner ends adjacent the hub 58. The H-shaped retaining keys are then forced into place, and the couplings 2d are fixed to the stub pipes carried by each receptacle, and the control valves 28 are opened. It will thus be seen that the entrance for the preserving liquid is disposed between the innermost end of the tie and the backing plate 32, and at the same time entirely surrounds the tie except for the central part of the outer end of each tie. The machine is then set in motion and the preserving liquid is allowed to enter each case. Since the ties are radially disposed with relation to the axis of rotation, the centrifugal force set up by the machine will force the creosote, or other preserving liquid, longitudinally through the ties in the di rection of the sap ducts, which are naturally present in the wood. .The creosote is thrown off from the outer end of the tie and drops into the pit and may be re-used, and, by being retained, it may easily be estimated as to the quantity of preservative retained by each cubic foot of wood treated.

It has been found that when the speed of a machine fourteen feet in diameter is approxi- I mately 40 to 90 R. P. IVL, a liquid as heavy as creosote oil will entirely impregnate green or undried oak ties impartially through both heart and sap wood and flow from their outer ends in a space of about two minutes. It will be appreciated that represents an enormous saving in time over the old methods, which required that the oak ties be dried approximately one year before being treated. It will be seen that the preserving liquid is forced by the centrifugal action set up by the rotation of the machine lengthwise through the sap ducts of the tie and allowed to flow freely from the outer end since the casing ill is open at this point.

While I have disclosed one machine which is suitable for carrying out my method, it should be expressly understood that this disclosure is made purely by way of illustration, and that the method is capable of practice with various other machines and that numerous changes may be made in the form and disposition of the parts without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent, is:

1. The method of treating wood. With a preserving liquid which consists in rotating green or undried wood about an axis with its grain or ducts radial of the axis and introducing the preserving liquid at the point nearest the axis of rotation, whereby centrifugal force causes the preserving liquid to flow longitudinally of the grain or ducts.

2. The method of treating wood with a preserving liquid which consists in placing a piece of green or undried wood to be treated in a casing having one end substantially open, rtating the wood and casing about an axis with the grain of the wood radial of the axis and introducing the preserving liquid into the casing at a point near the axis of rotation whereby centrifugal force causes the liquid to flow through the wood longitudinally of the grain, and out of the open end of the casing.

3. The method of treating wood with a preserving liquid which consists in rotating green or undried woodabout an axis with its grain or ducts radial of the axis and introducing the preserving liquid at the point nearest the axis of rotation, sealing the outer part of the outer end of the wood by centrifugal force whereby the same centrifugal force causes the preserving liquid to flow longitudinally of the grains or ducts.

4. The method of treating wood with a preserving liquid which consists in placing a piece of green or undried wood to be treated in a casing having one end substantially open, rotating the wood and. casing about an axis with the grain of the wood radial of the axis and introducing the preserving liquid into the casing at a point near the axis of rotation whereby centrifugal force causes the wood to be sealed at its outer end against the casing and the liquid to flow through the wood longitudinally of thegrain, and out of the open end of the cas- FRANK W. CHERRINGTON.