Timber Planer

The term timber planer implies that plain knives only are used in the machine, which is therefore intended for producing plane surfaces. It also implies that the machine is designed for heavy or large work, such as is found in ship yards, bridge construction or car works, etc., etc.

In such work the cuts taken by the machine are sometimes very heavy, and as a result the feed works of the machine require to be very powerful and positive.

Fig. 3183 represents a timber planer designed and constructed by J. S. Graham & Co., to plane all four sides of the timber at one passage through the machine.

The timber passes through three pairs of feed rolls before reaching the first cutter head, which planes the bottom surface.

It then passes to the side heads, which dress both sides simultaneously, and then passes beneath the cutter head that finishes the upper surface, and is finally delivered from the machine by a pair of delivery rolls.

The work is passed over roller b, the fence or gauge being shown at b′. 1 and 2 are the first pair of feed rollers, a and b being merely adjustable intermediate wheels, which by means of the pieces c′, b′, may be set so as to connect rollers 1 and 2 together, whatever their distance apart may be, or in other words whatever the thickness of the work may be.

From 1 and 2 the work passes to the second pair of feed rolls 3 and 4, c and d being the intermediates.

Similarly 5, 6, 7 and 8 are feed rolls, and e, f, g, h intermediates. The first head is shown at k′, the side heads at h, and the last head at i′, the latter being carried on a sliding head j, which is secured in its adjusted position by nuts i. On the side of the frame d on which j slides is a graduated index to denote the adjustment of the head i′.

The construction of the parts in immediate connection with the front cutter head is shown in Fig. 3184. n is the frame corresponding to n in Fig. 3183, the rolls 5 and 6 also corresponding in the two figures.

Upon n is a slide s having an arm g, carrying the roll g′, which holds the timber down to the cut of the cutter head k′. The pressure of roll g′ to the work is given through the medium of the rod a′, which receives the pressure of the equalizing bar x, Fig. 3183.

The bottom surface of the timber passes over the bed plate u, Fig. 3185, which raises and lowers with the lower feed rolls, being connected by the screw i, Fig. 3184, to the bearing box of feed roll 6.

All the lower feed rolls are operated simultaneously by means of the rod l, having for each lower feed roll a worm, driving a worm wheel l′ on a screw threaded into a hub m in each feed roll bearing; the crank for operating l is seen at p, Fig. 3183.

The passage of the timber through the machine is continued in Fig. 3185, in which it is seen that after the lower surface of the timber has been planed it passes from the cutter head k′ to a bed plate v and is thus supported by a flat and true surface while the side cutter heads plane the two sides, one of these side heads being shown at h. The side heads are carried in hangers, one of which is shown at p′. It is gibbed to the under cutter frame u′ by the sliding gib x, the left hand head h being moved across the frame by the screw f′. The hanger is held at the bottom by the gib t and the cross tie t′. p is the pulley for the side head h, the end wear of whose shaft is taken up by the adjusting screw s′, r′ being a leather washer, and r the end of the shaft.

The top box h′ moves across the machine in the slideway b′′, Fig. 3186, a′′ being a part of the box h′.

Upon leaving the side heads the timber will have been planed on three sides and the side surfaces dressed to a right angle with the bottom surface.

It is then guided to the upper cylinder as follows:

The friction rolls k, k are to relieve the bed a′′ from the pressure due to the feed roll z′ and the roll j′, which holds the timber after it has left the cutter i′, and thus prevents it from vibrating. After leaving the pressure roll j′, the timber passes under the scraper d′, Fig. 3183, and thence to the delivery roll 7, which is held down by the weight l, in connection with the lever l′.

By means of this construction all the cutter heads act upon the timber within the short distance of 22⁄2 inches, while the side heads act within 8⁄2 inches of the under cutter. This is desirable, being conducive to the production of true work, which it is more difficult to produce in proportion as the cutter heads are wider apart. This machine will joint as narrow as 2 inches, and plane as thin as ⁄4 inch.

The upper cylinder i′, Fig. 3183, is adjusted for height or thickness of cut by means of the screw f, and is locked in its adjusted position on d by the nut i.

The feed is started or stopped by operating the hand wheel o′.

The upper rolls are raised or lowered simultaneously by power, by means of the shaft s, and the bevel gears r, which operate the screw a′.

The upper cylinder is driven by belt from the pulley q, the under cylinder from q′ (both these cylinders being driven from both ends). p′ is the driving pulley for the feed belt, which passes to n′, which, through k′′ and y′, drives y, which drives the feed rolls.

The machine will feed from 25 to 60 feet per minute.