This method is refrered to, and drawings given, in the text, pp. 141, 142.
1829. A Investigation into the Origin and Mode of writing the Cuneiform
Character
This will be found described in the next and final chapter
1836. A Machine for cutting the Key-Grooves in Metal Wheels and Belt Pulleys, of ANY Diameter.
The fastening of wheels and belt pulleys to shafts, so as to enable them to transmit rotary motion, is one of the most frequently-recurring processes in the construction of machinery. This is best effected by driving a slightly tapered iron or steel wedge, or "key" as it is technically termed, into a corresponding recess, or flat part of the shaft, so that the wheel and shaft thus become in effect one solid structure.
The old mode of cutting such key-grooves in the eyes of wheels was accomplished by the laborious and costly process of chipping and filing. Maudslay's mortising machine, which he contrived for the Block machinery, although intended originally to operate upon wood, contained all the essential principles and details required for acting on metals. Mr. Richard Roberts, by some excellent modifications, enabled it to mortise or cut out the key-grooves in metal wheels, and this method soon came into general use. This machine consisted of a vertical slide bar, to the lower end of which was attached the steel mortising tool, which received its requisite up and down motion from an adjustable crank, through a suitable arrangement of the gearing. The wheel to be operated upon was fixed to a slide-table, and gradually advanced, so as to cause the mortising tool to take successive cuts through the depth of the eye of the wheel, until the mortise or key-groove had attained its required depth.
The only drawback to this admirable machine was that its service was limited in respect to admitting wheels whose half diameter did not exceed the distance from the back of the jaw of the machine to the face of the mortise tool; so that to give to this machine the requisite rigidity and strength to resist the strain on the jaw, due to the mortising of the key-grooves, in wheels of say 6 feet diameter, a more massive and cumbrous frame work was required, which was most costly in space as well as in money.
In order to obviate this inconvenience, I designed an arrangement of a key-groove mortising machine. It was capable of operating upon wheels of any diameter, having no limit to it capacity in that respect. It was, at the same time, possessed in respect of the principle on which it was arranged, of the power of taking a much deeper cut, there being an entire absence of any source of springing or elasticity in its structure. This not only enabled the machine to perform its work with more rapidity, but also with more precision. Besides, it occupied much less space in the workshop, and did not cost above one-third of the machines formerly in use. It gave the highest satisfaction to those who availed themselves of its effective Services.
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A comparison of Fig. 1—which represents the general arrangement of the machine in use previous to the introduction of mine—with that of Fig. 2, may serve to convey some idea of their relative sizes. Fig. 1 shows a limit to the admission of wheels exceeding 6 feet diameter, Fig. 2 shows an unlimited capability in that respect.