US67978A - Melancthon hanford - Google Patents

Description

@einen taies germi @fitta IMPROVEMENT IN ROTARY ENGINES.

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TO ALL WHOM IT-MAY CONCERN:

Be it known that I., MELANCTHON HANFORD, of Boston, in the county ofSuifolk, and State of Massachusetts, have invented an Improvement in Rotary SteamV Engines; and do hereby declare theV following to be a full, clear, and exact description thereof, due reference being had to the accompanying drawings, making part of this specification, and in'whichi Figures 1 and 2 are side views of the said-engine with cap-plate removed.

Figure 3 is a longitudinal and horizontal section, and

Figure 4 a transverse section of it: t 4 i I Figure 5 is a vertical section ofl its induction and exhaust-chambers, and

`Figure 46 al representation of its two pistons.

The object of this invention, which is an improvement in that class of steam engines known as .rotary engines, or those in which two pistons, revolving in 'opposite directions and geared together, are employed, is to increase thelevcrage or power of the engine as a motor, by-increasing vthe length ofrsteani-bearing' and propelling surface ofthe pistons,this being accomplished by making projections or arms upon the circumference of the pistons which mesh into notches or recesses formed in the other, the projections serving to partially rotate the pistons nwhen in contact, and to form a steam-bearing surface or leverage to aid in propelling them, the two pistons being further connected together by a quadrangular series of sectional gears formed upon or making part of the circumference vof the piston, as hereinafter explained.

By referring to the accompanying drawings illustrating my invention, the box or casing of the engine is shown at A, having parallel cylindrical bores or chambers a a! intersecting each other and uniting to form one largeV chamber, A; and4 further, having steam-induction and exhaust-chambers 6 c below the chambers a The revolving pistons are shown at B Bas yapplied within the chambers a a respectively, and seas to rotate in close proximity to opposite sides of the chambers, the pistons being supported by parallel shafts d al sustained by .the walls of the casing-A. The pistons are circular in form, and have quadrangularly-arranged sectoral gears e e e e cut upon their peripheries, the teeth of one piston meshing into those of the other, and each piston bein also formed with two roections fff and notches or recesses on its o osite sides, and` g P J .9 .9 g .9 PP

approximating to a. semicircle in form, and between the sectoral gears e e e e, as represented in figs. 1 and 2 of the drawings. Thetwo pistons are grooved longitudinally on opposite sides, for receiving steam-packing plates heh,

a small chamber, z', being formed in each en`d of the piston and between thetwo plates, and having a lateral opening, j, to allow steam to enter Vthe chambers z'eand force the plates against the interior faces ot the chambers a a', thus preserving a steam-tight joint between the faces of the pistons and their case. Additional chambers c Icare formed vertically in each end of the projections or teeth ffj" f of thelpistons for receiving packing-plates Z Z, secured therein in any suitable manneijand supplied with springs to force them outward and in contact with the inner periphery of the case A, by this means preserving a steam-tight joint about the ends of the pistons, in the same manner that the plates L 7L eiect their object, the steam being admittedv to contact with the 'last-mentioned chambers k by a portl leading from the chambers it, before mentioned. vThe steam.. induction port leading into the piston-chamber A is shown at 1n, and the eduction or exhaust-port atn, the

vport m leading from the steam-supply chamber b, and the port 'n opening into the exhaust-chamber c, the chambers b and c being provided with suitableinlet and outlet passages s t.

In the operation of the above-described engine, when used as a motive power, and supposing the two pistons to be in thel position shown in fig. 2 of the accompanying drawings, the steam entering the induction-port m impinges against the tooth or'projection-f orf of the piston B and rotates it inthe direction indicated by the arrow thereon, thesectoral gears eat this time meshing into `one of those o'f the piston B and aiding in rotating the said piston B in an opposite direction, or that indicated by itsarrow a, the rotation of this piston being also aided by the pressure of the steam upon its tooth f and upon the upper portion of its recessl g', the steam being prevented from passing between-the pistons when inthis position by the teeth of. the gears e e, and when in the position shown in iig. 1, by the steam-packing plates l Z operating upon the interior of the recesses g y.

Under the conjoint action above described the two pistons will be rotated until the gears are out of engagement and one of the teethf of the piston B takes into the notch g of the piston B, the action oi' the toothf' and notch g serving, in conjunction with the pressure of the steam, to bring the two pistons into the position to allow the two next adjacent gears e e to mesh into each other and complete, with the aid of the steam, a semirevolution ofthe two pistons on theiraxes, or into the position shown in iig. 1 ofthe drawings, when the exhaust steam will pass through the port n and into the exhaust-chamber c, and from thence into the atmosphere.

The action of the packing-plates L h and l Z during the different positions of the pistons will readily manifest themselves to persons conversant with steam, as their construction and operation has been before explained. The advantage gained in power by my construction and arrangement of the' pistons is dependenton the length of the teeth ff of the piston B, the excess of length ofthesc teeth beyond the periphery of the circular porv' tions of the pistons determining the extent of the gain. When lthe two pistons are in the position shown in iig. 1 the advantage gained is not so great, as thel increase in power gained by the action of the steam o'n the outer end of the piston A is to some extent lost in acting as a` motivepower upon the piston A', although theL steam comes in at this point to act upon this piston and serve as an auxiliary to counteract this loss. But the full advantage of the increased length of the piston, by means of its teeth ff, is gained when the positions ot' the pistons are changing from that shown'in fig. 6 to that shown in fig. 1, as the periphery of the gears is equidistant from their centres, while the toothj` of thepiston B, is projected beyond the circumference of these gears, the increase in the leverage or power of the steam upon the tooth' increasing.very'rnpidly as it departs from the circumference of the piston. By the arrangement ofthe recesses y y of the piston B room is made for ydisposing of the tcethff, while the teeth act at the same time as motors to the said piston. By the mode of. connecting or gearing the two pistons together, as described, while gaining other and important advantages, I dispense with gears outside of the case A, and apply the machinery to be driven by the engine directly to the shaft of the said piston A.

I would remark that the above-described engine, although referred to in the specification as a motor, may be employed to excellent advantage as a water-meter. A

In this case I have contemplated constructing the pistons of hard rubber in place of metal, andmake the slightly elastic properties of the rubber perform the 'oflice of packing the joints in place of the metallic bars before described.

I do not claim broadly the combination in rotary engines of cog-pistons, for I am aware that the same is. 'described and claimed.` in 'the patent of B. Holley, February 6, 1855;.but what I claim as my invention, and desire to secure by Letters Patent, is f The herein-described arranvement of thesmaller iston B and laroer iston B, rovided with ro'ections e P e P P P J f, as and for the purposes set forth.

f MELANCTHON HA-NFORD.

Witnesses Fasucrs CURTIS, FREDERICK CURTIS.

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