With Auxiliary Boring Attachment.
171
No. 3 Large Patent
Automatic Hollow-Chisel Mortising and Boring Machine.
With Auxiliary Boring Attachment.,
The machine shown is intended for mortising all hinds and classes oftimbers, heavy and light, used in car and bridge construction. It is a powerfuland compact machine, automatic in its operation, and works with great rapidity.When once started, it will make any number of mortises without change.
The mortises are made by the reciprocation of a square hollow-chisel havingan auger revolving in its center, the chisel squaring the hole produced by theauger. The superiority of this method of mortising is apparent from the factthat the mortise is left in a completed condition, no cleaning out being required,and a mortise of any length can be made by continuously cutting one hole afteranother on the same line. The reciprocation of the chisel is automatic, and thework produced very rapidly by the ease with which the movements and adjust-ments can be made by the operator.
The bed supporting the timbers is massive, and capable of enduring thestrain it is subjected to in heavy work. It has adjustments for carrying it toand from the chisel for different thicknesses of material and depths of mor-tises. It remains at one height, and is movable endwise to produce the varyinglengths of mortises. There is a clamping arrangement for holding material inposition, stops for gauging the lengths of mortises, and for using templates inproducing duplicate mortises.
The chisel-frame and auger-spindle are carried on a heavy vertical columnwhich is connected to the base on which the bed for the timber is placed. Ithas a vertical movement on the column to allow the position of the chisel tobe varied up or down according to the desired position of the mortise. Thereare stops to regulate the height of the travel of the cliisel-frame, which is movedby means of the large liand-wheel, and has a device for locking firmly at theheight of the mortise, and easily moved up and down for double mortising.
The reciprocating motion of the chisel-frame is pi’oduced by a reversingfriction and gearing operating in a rack on the chisel-frame, the driving forcecoming very near the point of resistance of the chisel. The distance of travelof the chisel frame is controlled by adjustable stops. The countershaft is at-tached to the machine, driving the reversing friction by two belts, and a beltto the auger-spindle over a pair of idlers, one of which automatically adjusts tothe varying lengths of tfhe belt as the chisel is raised and lowei’ed.
The machine can be used for single and double mortising, for gaining, counter-sinking, end tenoning, and boxing. The chisel has a travel of 10" in depth, andthe vertical range of work is 13". Mortises can be made to 234" square. Thetable will receive material 1534" high. An auxiliary boring attachment can beadded to the machine if desired. The machine is furnished with 1", 1
and 134" chisels and augers. A shop number is attached to each machine, refer-ence to which in correspondence will identify the class of the machine and thestyle of its construction.
The tight and loose pulleys are 12" x 6", and should make 1,000 revolutions.