US590511A

US590511A - Engine

Info

Publication number: US590511A
Authority: US
Publication date: 1897-09-21
Anticipated expiration: 1914-09-21

Description

5 Sheets-Sheet 2.

(No Model.)

(No Model.) 5 Sheets-Sheet a.

J. BOYER. ENGINE.

No. 590,511. Patented Sept. 21,1897.

5 Sb eefs-Sheet 4.

(No Model.)

J. BUYER.

ENGINE.

No. 590,511. Patented Sept. 21,1897.

(No Model.)

- 5 Sheets-Sheet 5.

J. BOYER. ENGINE.

No. 590,511. Patented S ept. 21,1897.

M 1 x E f 27/422; 9

warms ca. movoun-ub. wAsl-cmmcu, mz.

UNITED STATES PATENT OFFICE.

JOSEPH BO YER, OF ST. LOUIS, MISSOURI.

ENGINE.

SPECIFICATION forming part of Letters Patent No. 590,511, dated September 21, 1897. Application filed February 5, 1897. Serial No. 622,146. (No model.)

To all whom it may concern.-

Be it known that I, JOSEPH BOYER, a Gillzen of the United States, residing at the city of St. Louis, in the State of Missouri, have invented a certain new and useful Improvement in Engines, of which the following is a description, reference being had to the accompanying drawings, forming part of this specification.

My novel engine belongs to that class in which a rotary frame carries a plurality of cylinders whose piston-rods are connected to a fixed pivot or crank pin eccentric to the axis of the rotary frame, whereby the action of the motive fluid upon the cylinders and pistons causes the rotation of the frame carrying the cylinders. It has been designed primarily for use as the motor part of a rotary drill to be operated by compressed air, and has been illustrated in the accompanying drawings as part of such a machine. It is applicable, however, to many other uses of an engine and embodies essential features of novelty as an engine per 86, so that my present invention relates both to the engine itself, for whatever use it may be applicable, and

also to its combination with the other elements making up a rotary pneumatic drill. In addition to this the elements combined with the engine for this purpose in the present instance embody essential features of novelty in themselves apart from the novel features of the engine itself, all as will be hereinafter more fully explained, and particularly pointed out in the claims.

It is the object of my invention to produce a small and compact light running highspeed engine of maximum power in proportion to its size and weight and which shall be perfectlybalanced and especiallysuitable for use as the motor of a light portable nn'i-nually-handled rotary drill or for other purposes for which a small powerful highspeed engine is desirable. These results I accomplish in the manner and by the means to be now described by reference to the accompanying drawings, which illustrate one form and embodiment of the several features a transverse vertical section of the same;

Fig. 2, a sectional detail illustrating the adjustable stop for the throttle-valve; Fig. 2 a detail of the binding-nut and locking-ring therefor; Fig. 2, a detail of one of the bait bearings; Fig. 3, a horizontal section ap proximatelyon the line 3 3 of Fig. 2, exhibiting a top plan view of the rotary frame carrying the several cylinders and the upper bearing of said frame; Fig. 4, a horizontal section approximately on the line 4 4 of Fig. 2; Fig. 4:, a detail View showing the manner of securing the cylinder-heads to the cylinders; Fig. 5, a horizontal section approximately on the line 5 5 of Fig. 2; Fig. 6, a horizontal section approximately on the line 6 6 of Fig. 2, being a top plan view of the lower cap of the casing and the parts within the same; 7, a perspective view of the rotary frame carrying the cylinders, the fixed upper bearing for said frame, and the rotary shaft depending from the under side of said frame; Figs. 8, 9, 10, and 11, details of the valve for controlling the inlet and exhaust of the motive fluid at the outer end of one of the cylinders, Fig. 8 being an elevation of said valve, looking at its inner face, 'Fig. 9 a vertical section indicated by the dotted line 9 9 of Figs. '7, 10, and 11, and Figs. 10 and 11 vertical sectionson the lines 10 10 and 11 11 of Figs. 8 and 9; and Figs. 12 and 13, details of a modified form of valve.

The same letters of reference are used to indicate corresponding parts in the several views.

The engine part of the machine shown in the accompanying drawings is inclosed within a cylindrical shell or casing A, closed at its upper end in the present instance by an integral head or cap B and at its lower end by a removable head or cap 0. In the machine shown in the drawings this lower head or cap C constitutes a diaphragm which separates the engine-chamber within the casingA from a chamber beneath said diaphragm within a removable cap D, which latter chamber contains the speed-reducing gearing and other parts intermediate the engine proper and the drill or other tool driven by it. The diaphragm C fits at its outer edge between the lower end of the casing A and upper end of the cap D and is held in place and the three members secured together by screws E E,

passing through holes in a peripheral flange formed around the upper end of the cap D and in the outer edge of the diaphragm C and entering the lower end of the cylinder A.

Under the particular construction and arrangement of parts shown in the drawings and the particular method and mode of operation in which the motive fluid is utilized to drive the rotary frame of the engine under such construction and arrangement of parts the engine-chamber within the cylinder A is a live-air chamber, to which the motive fluid under pressure is constantly admitted during the operation of the machine, while the chamber within the lower capD of the casin g is an exhaust-chamber constantly open to the outer air by holes F F in its lower side, the two chambers being separated from each other at the center of the diaphragm C by an air-tight joint around the rotary shaft which passes through the diaphragm, as hereinafter explained. To enable the diaphragm O to be made as light as possible consistent with the strength and rigidity necessary to withstand the pressure of the motive fluid within the casing A, it is crowned upward, as shown, and also provided upon its under side with radial ribs G.

Located within the casing A is the rotary frame which carries the several cylinders. In the present instance these cylinders are three in number, and to avoid unnecessary weight of metal said frame is therefore made approximately triangular in shape or provided with three equidistant arms or extensions which carry the several cylinders. A perspective view of this rotary frame and the parts carried by it is shown in Fig. 7, while a top plan View is shown in Fig. 3, a middle horizontal section through the centers of the cylinders in Fig. 4, and a lower horizontal section through the exhaustpassages in the lower plate of the frame in Fig. 5, a vertical section through the frame and one of the cylinders and itsvalve being shown in Fig. 2. As seen in Fig. '7, this rotary frame in the present instance consists of an upper plate H and a lower plate I of corresponding shape and rigidly secured together at the outer ends of their three projecting arms by the vertical pivots upon which the cylinders oscillate, said pivots in the present instance constituting the Valves which serve to admit and exhaust motive fluid from the outer ends of the cylinders as the latter oscillate from one position -to another in the revolutions of the rotary frame, as hereinafter described,

As shown in Fig. 2, the rotary frame has a central bearing at both of its upper and lower sides, its upper bearing being upon a short shaft J, secured in fixed position in the upper cap B of the casing A and extending through a central circular opening in the plate H, and the lower bearing of the frame being afforded by a central hollow shaft K, firmly secured to or formed integral with and depending from the lower plate I of the frame and having a bearing in the diaphragm O, as hereinafter described. The shaft J, upon which the upper plate of the rotary frame has its bearing, has formed integral with and depending from its lower end, at one side of its center and consequently eccentric to the axis of the rotary frame, a pin or post L, Which forms the fixed eccentric pivot to which theinner ends of the piston-rods are connected and about which as a center the pistons revolve in the movement of the rotary frame, as hereinafter described. The shaft J and eccentric-pin L thus constitute a fixed crank secured in the upper cap B of the casing, to which end the shaft J has an enlarged lower portion and a reduced upper portion, forming an upwardlyfacing shoulder at their junction, the reduced upper portion fitting in a central circular openingin the cap B, while the shoulder abuts against the under surface of the cap around the opening therein and forms a tight joint. The reduced portion of the shaft J is provided with a projecting lug or key a, which fits in a vertical groove or keyway formed in the wall of the circular opening in the cap B to positively hold the shaft from turning. The extreme upper end of the shaft is still further reduced and screw-threaded exterior-1y to re- 5 ceive a nut M, which is screwed firmly upon it and bears against the upper surface of the cap 13, around the circular opening therein, and serves to bind the shoulder of the shaft J firmly against the lower surface of thecap B and hold the shaft securely in position. For the purpose of preventing the nut M becoming loosened there is provided a check- -ring N, which, as shown in Fig. 2', surrounds and fits the polygonal surface of the nut and is provided with curved slots Z), through which pass screws 0, entering the cap B. In assembling the parts the nut M is first screwed up tight, and the check-ring N then slipped over it in position for its slots Z) to register with no the screw-holes for the screws 0, and then the screws 0 are inserted through the slots 1) in the ring and screwed firmly into the cap 13 to securely hold the ring in place, after which any further limited adjustment of the nut M 1 15 will be permitted by loosening the screws 0 without removing them, the slots in the checkring N permitting it to be turned with the nut M within a limited distance independently of the screws 0. V

The enlarged lower portion of the shaft J is provided with a peripheral V-shaped groove (1, while the central circular hole in the upper plate H of the rotary frame has driven into it ahardened ring 6, provided with a correspond- I2 5 ing groove. Confined in these grooves between the ring 6 and shaft J are balls f to relieve the friction between the parts. These balls are placed in position after the shaft J has been inserted through the ring (2 and the 130 two grooves brought opposite each other, and to permit such insertion of the balls the shaft J is provided in its lower end, near its outer edge, with a vertical hole g, (indicated by dotted lines in Fig. 2 and shown in full lines in Fig. 2 which hole communicates at its upper end bya lateral passage with the groove (Z. The balls fare inserted one by one through this hole and passage into the track around the shaft J, and when the necessary number have been so inserted an extra ball is inserted in the hole g and confined in the upper end thereof by a screw-plug screwed into said hole, such extra ball serving to close the passage between the upper end of the hole g and the groove d and preventing any of the regular balls f entering said passage.

The lower bearing for the rotary frame and the air-tight joint around its hollow shaft K at the center of the diaphragm O, by which the live-air chamber within the casing A is separated from the exhaust-chamber beneath the diaphragm O, are as follows: The diaphragm C is provided upon its under surface with a circular boss i,surrounding the central opening through which the shaft K passes, and formed in this boss upon the upper surface of the diaphragm O are two annular seats surrounding the central opening in the diaphragm. Into the lower smaller one of these seats is fitted a hardened ringj of rightangular shape in cross section, while surrounding and snugly fitting and, if desired, tight upon the shaft K is a hardened sleeve 7t, provided at its upper end with a projecting flange. Between this sleeve and the ring are placed the series of ballsZ to relieve the friction of the bearing.

For the purpose of rendering this joint around the shaft K air-tight there is fitted within the upper and larger of the two annular seats formed in the upper surface of the diaphragm C a washer m, of leather or other suitable material, which surrounds the shaft K immediately beneath the lower plate I of the rotary frame. This washer m covers the joint between the upper edge of the ringj and the flange of the sleeve is and projects outward some distance beyond such joint and is held firmly against its seat and the upper edge of the ringj and flange of the sleeve 70 by the pressure of the motive fluid within the casing A, so that a tight joint is maintained between the under surface of the-washer and the parts upon which it rests, leaving no opportunity for escape of motive fluid from the engine-chamber to the exhaust-chamber be- 11 eath. The sleeve 75 rotates with the shaftK as the rotary frame turns, while the washer m remains stationary, so that the only moving surfaces in frictional contact with any considerable pressure between them are the upper surface of the flange of the sleeve 71; and that portion of the under surface of the washer m which bears upon said flange, the pressure between these parts being, however, only such pressure as may be exerted upon the upper surface of the washer m by the motive fluid. In this manner I provide asubstantially air-tight ball-bearing for the lower end of the rotary frame, the onlyfriction not surrounding the pin L.

relieved by the ball-bearin gs being that above indicated between the flange of the sleeve 70 and the under surface of the washer m.

Referring now to Figs. 2 and 4, the construction of the three cylinders O, O, and 0, carried by the rotary frame, and the manner in which the motive fluid acts upon them and their pistons to rotate the frame may be explained. In order that the bodies of the cylinders may preferably be formed of wroughtsteel, while the heads P thereof may be cast, the bodies and heads of the cylinders are formed separately and secured together, and in order that both the cylinder and its head may be as light as possible I employ the following means for securing the head P to the cylinder instead of screwing one upon the other or otherwise fastening them together:

At its extreme outer end the wall of the cyl-' inder is slightly thickened around its edge or provided'with an outwardly-projecting beveled flange a, as more clearly appears in the enlarged detailed views in Fig. at. The cylinder-head P (preferably made of bronze) is provided with a circular groove 1) of Suficient width and depth to receive this flanged end of the cylinder, and when the latter has been seated in the groove the edge of the cylinder-head surrounding the groove bis spun over upon the surface of -the cylinder to tightly inclose the flanged end thereof, thus firmly securing the head to the cylinder and forming a tight joint between them.

Each cylinder-head P has formed upon its outer side a vertical sleeve or casing Q, which sleeves surround and snugly fit the vertical pivots R,'by which the plates H and I of the rotary frame are rigidly secured together at the outer ends of their three radial arms, as previously mentioned and as hereinafter more fully described.

The pistons S, fitting in the respective cylinders,are cup-shaped in the presen t instance, and the piston-rods T are rigidly secured to them. The inner ends of two of the pistonrods T are forked,and each fork carries a strap surrounding the crank-pin or flxed eccentric L, heretofore referred to, while the third rod is provided wit-h a single wider strap likewise The strap of this latter rod occupies the middle position on the pin L and is embraced by the straps of the other rods, as shown in Fig. 2. These straps surrounding the pin L are of considerably greater internal diameter than the pin and have driven into them hardened rings V, provided upon their inner surfaces with V-shaped grooves, the ring fitting in the wider middle strap being provided with two such grooves,

and inserted into each of the sin grooves in the rings V is a series of balls IV to relieve the friction which would occur between the straps and pin L were the straps fitted directly to said pin.

As heretofore stated, the pivots R upon which the cylinders oscillate constitute valves for admitting the motive fluid to and exhaust- ICC ing it from the outer ends of the cylinders behind their pistons, and in the present instance these pivots R also serve as the means for securing together the opposite plates 11 and I of the rotary frame, although this latter function might be performed by other suitable posts or bolts if the two plates of the rotary frame consisted of circular disks or were otherwise suitably shaped to accommodate such independent means for securing them together. In the present instance each of the pivots or valves R consists of an internally-bored post or tube, whose interior is separated into an upper chamber B and a lower chamber 13" by an intermediate partition X, as seen more particularly in Figs. 2, 4, 8, 9, 10, and 11. At its upper end each of the tubes R is slightly reduced in diameter to tightly fit a circular opening in the outer end of one of the arms of the upper plate H of the rotary frame, the shoulder formed at the lower end of such reduced portion abutting against the under side of said plate. The interior of the upper end of the chamber B of the tube is threaded to receive a hollow flanged screw Y, Fig. 2, which serves to firmly secure the upper end of the tube in the plate without obstructing the entrance to the upper end of its chamber B, which latter is left open and in free communication with the interior of the casing A at all times.

To the more firmly secure the tubes in the plates H and positively hold them from turning therein, their upper ends may be suitably keyed or pinned in said plate in addition to being held thereto by the screws Y. The lower ends of the tubes R are likewise reduced in diameter to tightly fit openings in the outer ends of the arms of the lower plate I of the rotary frame and are internally threaded to receive flanged screws Z, which serve to firmly secure their lower ends to said plate and also close the lower ends of their internal bores or chambers 13, the flanges of the screws Z forming a tight joint against the under surface of the plate I. The reduced lower end of each of the tubes R, which fits in the hole in the plate I, is provided about midway of its length with a circumferential groove, which communicates with the internal bore of the tube by a series of ports 02, Figs. 2 and S to 11.

These ports and grooves also communicate with an exhaust-passage 0, formed in the plate I and leading to the center thereof and communicating at its inner end with the internal bore of the hollow shaft K, whose upper end is secured in or formed integral with the plate I, as heretofore explained, Figs. 2 and 5.

As seen in Fig. 5, each of the three arms of the plate I has formed upon its upper side a radial housing or hollow rib A, whose internal passage 0 communicates at its inner end with the internal bore of the hollow shaft K and at its outer end with the lower end of the internal bore of the tube R. The hollow shaft K opens at its lower end into the exhaustchamber in the lower part of the casing of the her B, and the lower one 0 machine, and thus serves, through the medium of the exhaust-passages 0 in the plate I, to place the chambers B of all the tubes R in constant communication with the exhaust.

Out through the inner wall of each tube R are two vertical slots 0" and O, the upper one C communicating with its live-air chamcommunicating with its exhaust-chamber B". These two slots constitute ports for admitting live air to and exhausting it from the outer ends of the .cylinder, and to that end the cylinder-head is provided wit-ha vertical slot D, extending across nearly its full diameter, Fig. 2. When the cylinder is turned upon the tube R to position for the port O to register with its port D, live air will be admitted to the outer end of the cylinder from the valve-chamber B and live-air chamber within the casing A, and when it is turned to position for the port 0" to register with its port D the port 0 will be closed and communication with the live-air chamber be out 01f, and communication with the exhaust be opened through the port 0, chamber B, and passage 0. i

For the purpose of facilitating the inlet and exhaust of the motive fluid when the ports 0' and O" are respectively brought opposite the port D in the cylinder-head the side of the valve-tube R facing the center of the machine is provided with a groove E, forming a downward vertical extension of the port 0' upon that side of the tube, while a second groove E forms a like upward vertical extension of the port C upon the same side of the tube, Fig. 8, so that when either port is brought opposite the port D in the cylinder-head the motive fluid may not only pass directly through the port but also pass along the groove leading to such port, and thereby facilitate its escape through the port. It is for the same purpose that the port D in the cylinder-head is made to consist of a long slot extending nearly across the cylinder-head, instead of consisting of two separate ports located in vertical line one above the other, so as to register, respectively, with the ports C and O" of the valve.

Having now described the construction and arrangement of the cylinders and pistons and valves, the operation of the engine may be next explained, as follows, reference being had more particularly to Fig. 4: In that View the section through the respective valves R is taken at a point above their diaphragms or partitions X, so that the internal bores of the valves there shown are the live-air chambers B thereof, while the ports shown in solid lines extending entirely through the walls of the valves are the live-air ports 0 for admitting live air from the engine-chamber within the casing A to the outer ends of the respective cylinders, and the grooves E" shown are the grooves communicating with the exhaustports C, Fig. 8. lVhen the motive fluid is (by opening'the throttle-valve hereinafter described,) it will flll said chamber and 'freely' enter the open inner ends of all thecylinders and exert its pressure against the innersides of all the pistons S, and will also exert its pressure against the exterior surfaces of all the cylinders and their heads P. This pressure of the motive fluid against the outer surfaces of the cylinder-heads Ptends to force the cylinders inward upon their pistons toward the fixed center L, about which the pistons revolve. So long, however, as the motive fluid is admitted through the valves to the outer ends of the cylinders behindtheir pistons the pressure therehy exerted against the inner sides of the respective cylinderheads will .counterbalance the pressure exerted against their outer sides and tend to force them inward, but when the motivefluid in the outer end of any cylinder behind its piston is permitted to exhaust through the valve R of such cylinder the counterbalancin g pressure against the inner side of the cylinder-head will be thereby removed and the pressure upon the outertside thereoftpermitted to force the cylinder inward upon its .piston. Now under the position of the parts shown in Fig. 4 the port D in the head P of the cylinder 0 is in register with-the exhaustgroove E and port 0 of its valve :R. The port D of the cylinder 0' is not in register with either of the ports of its valve, while the port D of the cylinder 0" is in register with the live-air port 0 of its valve. The exhaust from the outer end of the'cylinder O, behind its piston S, is therefore open, so that the counterbalancing pressure against thein-i ner side of the head P of this cylinder isremoved, leaving the pressure against'the outer side of the head free to force the cylinder inward upon its piston and thereby turn the rotary frame in the direction of the arrow. The inlet-port to the outerend of the cylinder O"being open, the motive fluid is free to enter and fill the space behind ,thepiston of this cylinder as the cylinder moves farther outward upon its piston in theforward move ment imparted to the rotary frame-by the action of the motive fluid upon the cylinder 0, as above described, while as the cylinderO is carried onward from the position shown in Fig. at it will be turned upon its valve R until its port D is brought into register with the inlet-port O of its valve, so that as said cylinder 0' moves toward the positionof the cylinder O in Fig. 4 the inlet-port to the outer end of said cylinder 0' will be opened .and the motive fluid permitted to enter-the outer end of said cylinder and fill the spacebehind its piston S as the cylinder 0' moves outward upon said piston. As the cylinder 0 is. carried onward from the position shown in Fig. 4: toward the position of the cylinderO in said view its port D will be moved out of register with the inlet-port C'of its valve and brought into register with the exhaust-port C" thereof, so that the motive fluid in the outer end of said cylinder .mayescape and the pressu re againstthe outer side of the cylinder-head be permitted to force the cylinder inward upon its piston, and thus apply the power of the cylinder 0 tothe turning of the rotary frame, and so on with each cylinder as they successively approach and pass the .position of the cylinderO in Fig. 4E. The exhaust from the outer endof each cylinder is opened some time before the cylinder reaches theposition of the cylinder 0 in Fig. 4 and visnot closed until the cylinder passes considerably beyondsueh position, so that the prespounds andis-so perfectly balanced that when runningat a-speed of a thousand revolutions per minute it maybe easily held-in oneshands without any considerable jar or strain,

Whilethe friction between its moving parts to 'the inlet-opening of the casing A and blowing into the chamber within.

For reasons hereinafter explained I con-' sider it highly advantageousto inclose the englue in an air-tight chamber and admit the motive fluid to said chamber under pressure, allowingit to pass therefrom to the outer ends of the cylinders through the ports in the valves and to-es'cape from the cylinders through the exhaust-ports of the valves and the passages leading therefrom and communicating with the exhaust-passage at the axis of the rotary frame, but without making any material .changeinthe construction-of the engine the mode of operation may be reversed and the is,so slight that it may be started and run at considerable speed by applying ones mouth chamber within the casing A be used as an exhaust-chamber, open to the outer air or the casing be entirely omitted, in the latter event theshaft J which carries the eccentric-pivot .L for the piston-rods being suitably supported in fixed position by other means. Thus the engine may be driven in reverse direction to that above described bysupplyin g the motive ,fluid to it through the hollow shaft K, whence it would pass through the radial passages 0 in the lower plate I of the rotary frame to the valves R,.and thence through the ports C" thereof and ports D in the cylinder-heads to the outer ends of the cylinders andescape therefrom through the port-s D and C and valve-chambers 'B to the interior of the easing A ordirectly to the outer air in event such casing were omitted. Under this reversed application of the motive fluid and reversed operation of the engine the power of themotive fluid in turning therotaryframe would be exerted against the inner sides of the respective cylinder-heads instead of against their outer sides and the cylinders be forced outward upon their pistons to turn the frame instead of being driven inward upon them in the manner heretofore described. Under this reversed operation also the upper plate H of the rotary frame might be dispensed with and the plate 1 be left to constitute the entire ro-' tary frame, the shaftK formingits entire support and bearing, the crank-shaft J in such case being dispensed with and the eccentricpivot L for the piston-rod otherwise suitably secured in fixed position, as has heretofore been sometimes done in engines of this class. As before stated, however, I prefer and consider it an important advantage to inc-lose the engine within an air-tight live-air chamber and apply the power of the motive fluid to the turning of the rotary frame by its pressure exerted against the outer sides of the cylinder-heads and operating to drive the cylinders inward upon their pistons. One advantage in this mode of operation is that the driving pressure of the cylinders upon the rotary frame to turn the latter is exerted against the outer sides of the valves Rinstead of against their inner sides, as would be the case under the reversed mode of operation above described. The outer sides of the valves B have solid walls, and therefore afford better bearing-surfaces for this driving pressure, less liable to wear than would the inner sides of the valves, which are mutilated by the presence of the inlet and exhaust ports.

Another advantage is that while the driving pressure of the cylinders upon the rotary frame is exerted against the outer sides of the valves R, yet during that part of their revolution in which the cylinders are balanced upon their pistons by the admission of the motive fluid to their outer ends behind their pistonsas, for instance, in the case of the cylinder 0" in Fig. ithe centrifugal force imparted to the cylinders causes their heads P or their sleeves Q, which surround the valves R, to press outward against the inner sides of said valves. The driving pressure of the cylinders is thusexerted against the outer sides of the valves while, on the other hand, the centrifugal force imparted to them is exerted in the opposite direction against'the inner sides of the valves, and the two forces acting upon opposite sides of the valves tend to equalize the wear upon the latter. Furthermore, the outward pressure of .the cylinder-heads against the inner sides of through the ports D in the cylinder-heads to find its way entirely around the valves and lubricate their entire surfaces in contact with the sleeves Q. Under the reversed mode of operation above described both the driving pressure of the cylinders and the centrifugal force imparted to them causes them to press against the inner sides of the valves and never against their outer sides during the operation of the engine, and the liability to wear between the parts thereby to that extent increased.

I One of the novel and most valuable features of my engine consists in the pivoting of the cylinders upon the rotary frame at or near their outer ends and admitting and exhausting the motive fluid through their pivotal supports. This construction and arrangement is believed to be entirely new in engines of this class and is highly advantageous for a number of reasons, among which is the fact that the length of the ports for admitting the motive fluid and exhausting it from the cylinder-s behind their pistons is reduced to the minimum, and the etficiency and economy of the engine thereby materially increased over any construction in which the motive fluid has to be admitted to the cylinders and exhausted therefrom through long inlet and exhaust passages of small capacity. This feature of my invention relating to the mounting of the cylinders upon the rotary frame at or near their outer ends and admitting and exhausting the motive fluid through their pivotal supports is not restricted to the particular construction and arrangement of parts nor to the specific mode of operation which I have shown and described for that purpose.

Any suitable construction, arrangement, and operation under which the motive fluid is admitted to the pivotal supports of the cylinders and permitted to pass thence to the outer ends of the cylinders and escape therefrom through ports opened and closed by the oscillations of the cylinders will embody to a greater or less extent the advantages of this feature of my invention and come within its broader scope. For instance, in Figs. 12 and 13 I have shown a modified form of valve constituting the pivotal support for the cylinder and cooperating with its port D to admit the motive fluid to and exhaust it from the cylinder. In this modified construction the valve is not tubular or provided with internal bores constituting live-air and exhaust chambers, but consists of a solid cylinder F, provided upon its inner face with two vertical grooves G G, the former communicating at its upper end with the live-air supply and the latter communicating at its lower end with the exhaust. The oscillation of the cylinder upon the valve as a pivot places these live-air and exhaust passages alternately in communication with the port- D in the cylinder-head to admit the motive fluid to and exhaust it from the cylinder behind its piston in the same manner as do the valves R in the main construction heretofore described. The grooves II, formed in the rear side of the valve F, Fig. 13, are provided solely for the purpose of admitting the motive fluid to the outer side of the valve to counterbalance the pressure at the inner side of the same. The valves R shown in the main construction are preferable to this modified form, since the ex terior grooves on the latter render them more liable to wear.

Again, under both the modification just described and the main construction heretofore explained the valves constitute fixed pivots upon which the cylinders oscillate, and the inlet and exhaust ports are automatically opened and closed by the oscillations of the cylinders upon these pivots, and this construction and operation are highly advantageous and desirable, but inasmuch as I believe myself to be the first in the art to mount the cylinders upon the rotary frame at or near their outer ends in an engine of this character and admit and exhaust the motive fluid through the supports upon which they oscillate, and inasmuch as this broad feature of novelty may be embodied-in an engine in which means may be employed for oscillating the valves to admit and exhaust the motive fluid at the outer ends of the cylinders instead of accomplishing that result by the oscillation of the cylinders upon fixed valves, and inasmuch as such a modification has been embodied in a successful engine built by me I desire it understood that this feature of my invention is not restricted in its broaderscope beyond the terms of the claims in which it is expressed. Where oscillating valves are employed to control the admission and exhaust of the motive fluid at the outer ends of the cylinders, it is of course unnecessary that the cylinders themselves should oscillate for that purpose, and in such cases they may therefore, if desired, be secured in fixed position upon the rotary frame, the piston-rods in such event being flexibly jointed to the pistons, as is common in engines of this class.

It will furthermore be evident to those skilled in the art that many of the novel features of my engine may be independently utilized to advantage in various old styles and forms of such engines, and without departing from my invention my new engine may be materially modified in the construction and arrangement of its parts in various ways suggested by the engines of the prior art, as will readily occur to those familiar with such engines.

Even where valves of substantially the same form and arrangement of the valves R are employed, it will be understood that instead of arranging the two ports and C" out of vertical line with each other, so as to cooperate with a single vertical port in the cylinder-head or with two ports therein in vertical line with each other, the cylinder-head may be provided with two ports arranged out of vertical line with each other and the ports C and C" of the valve be arranged in vertical line to cooperate with the respective ports in the cylinder-head.

lVhere, as under my preferred construction and mode of operation, the engine is inclosed within an air-tight live-air chamber, the motive fluid may be admitted to such chamber at any suitable point and in any desired manner. In the present instance I have shown it admitted to the casing A at the right-hand side of the latter in Figs. 1, 2, and 3 and near its upper end, and its admission controlled by a throttle-valve I, whose casing I is provided at its left-hand end with an exteriorlythreaded nipple screwed into an interiorlythreaded boss formed upon the side of the casing A. The valve-casing I has a straight passage through it opening at its left-hand end into the interior of the casing A, and interiorly threaded at its right-hand end to receive the threaded end of a nipple over which maybe slipped the usual flexible hose leading to the air-reservoir or other source of motivefluid supply. The valvel, fitting within the casing I and controlling the passage through it, is of common form, consisting ofatapering plug snugly fitting a chamber of corresponding shape in the valve-casing and provided with a passage J through it, and with a handle J at its lower end for turning it to bring its passage J into line with the passage through the valve-casing to open the valve or at right angles thereto to close it.

In Figs. 2 and 2 there is shown an adjustable stop by which the limit of opening movement of the valve can be regulated as desired. As there shown, the valve is provided near its lower end with a circumferential groove 0, into which projects the inner end of a stop-screw I), Fig. 2. The valve I is provided in this groove with two pins or lugs c c, the former of which abuts against the left-hand side of the stop-screw h when the valve is in closed position to limit its closing movement, while the latter cooperates with an adjustable stop cl, located in the groove a at the right-hand or outer side of the valve and movable therein. This stop consists of a curved plate fitting in the groove and provided upon its outer side with teeth which cooperate with a worm d, suitably mounted in a transverse bore in the casing I, and provided at its forward end with a finger-piece e, by which it may be turned to move the stop d back and forth in the groove 64.

In Fig. 2 the stop is shown in contact at its upper left-hand end with the stop-screw b, and the pin 0" of the valve is located in such position upon the valve that when the stop d is in the position shown the valve may be given a full quarter-turn in the direction of the arrow to fully open the passage through the valve before the pin 0 contacts with the end of the stop (1. By turning the worm (1, however, the stop d may be moved a greater or less distance toward the pin 0" in Fig. 2 and the opening movement of the ICO valve be thereby regulated as desired. This adjustable stop for limiting the openin g movement of the valve is believed to be new in a valve of this character; but another and more important feature of the valve, believed to be entirely novel, consists in the employment of its passage J as an oil-reservoir, by which a supply of oil may be placed in the path of the motive fluid and carried by the latter into the engine-chamber when the valve is opened to lubricate all the parts with which the motive fluid comes in contact. To this end the valve-casing I is provided with an oil-hole K, Fig. 3, communicating with the passage or chamber J in the valve when the latter is in closed position, as there shown. The chamber in the valve may be filled with oil through this hole K while the valve is in closed position, and when the valve is opened the rush of the motive fluid through the chamber J, particularly if the valve be opened slowly, will convert the oil into a spray or atomize it as it is carried into the engine-chamber, with the result that the -1notive fluid will be saturated with the lubricant and convey it to all parts of the engine.

So far as I am aware I am the first in the art to provide a throttle-valve of any character with an oil-chamber adapted to be filled with oil while the valve is closed and be brought into the path of the motive fluid when the valve is opened, so that the motive fluid may convey it to the parts to be lubricated, and this feature of my invention is therefore of corresponding scope.

Having now described my novel engine and set forth some of its advantages as such, I will next proceed to describe the additional elements which in the present instance are combined with it to make up the rotary pneumatic drill heretofore referred to, for which purpose reference is made more particularly to Figs. 2 and 6. As there shown, the hollow shaft K has keyed upon its lower end a pinion L, which meshes with two gears h' h which are mounted upon studs Q, secured in and projecting upward from the opposite ends of a rotary frame or cross-head N, and which in turn mesh with a circular rack Q, secured to or formed upon the inner face of the lower cap D of the casing A near its upper edge. The studs Q are provided with internal bores in their upper ends, which are closed, and the gears M M held in position upon the studs by flanged screws P". The chambers thus formed in the upper portions of the studsQ serve as oil-reservoirs from which oil may escape through holes a to lubricate the bearing between the hubs of the gears and the studs. The turning of the shaft K and pinion L in the direction of the arrow in'Fig. 6 by the operation of the engine will serve to turn the gears h M in the direction of the arrows upon them, while their engagement with the rack Q will cause them to travel around it and rotate the frame or crosshead N in the direction of the arrows upon it, the frame N being driven at a reduced rate of speed determined by the size of the pinion L relatively to the gears M M.

The rotary frame or cross-head N has a bearing in the lower end of the cap D, as follows: This cap is provided in its lower side with a large central opening into which is tightly driven aring or bushing P, which has formed upon its inner surface slightly above its middle an annular flange or ring R, upon the upper side of which rests a series of balls R. The rotary frame N is provided upon its under side with a cylindrical depending extension S, surrounding the central axis of the machine, and fitting around this cylindrical extension at its junction with the under side of the frame N is a hardened ring T, having a beveled outer surface resting upon the balls R, above referred to. The rotary frame N is thus supported upon the flange R of the ring or bushing I and the friction between the parts relieved by the balls R". The cylindrical extension S of the frame N is exteriorly threaded near-its lower end and has secured upon it a flanged ring U, having a beveled upper edge and snugly fitting with- V in the lower end of .the bushing P, and placed between the beveled surface of this ring U and the under side ofthe flange R of the bushing P is a second series of balls V. The ring U is provided with a notch f for the reception of a spanner-wrench with which to turn the ring, and it is held in adjusted position upon the cylindrical extension S by a lock-nut IV, screwed upon the extreme lower end of the extension S and likewise provided with a notch g for engagement by a spannerwrenchwith which to turn it.

The cylindrical extension S of the rotary frame N is adapted to receive within it the removable chuck or holder X, in which is inserted the drill or other tool or part to be driven by the engine. This chuck is provided at its upper end with an enlargement or head which has formed in one side a Vertical groove or keyway Y, in which fits a lug or screw Z, projecting from the inner surface of the extension S and serving to lock the chuck X to the rotary frame N and cause it to turn therewith. The chuck X is removably held in position by an exteriorly-threaded sleeve-nut Z, screwed within the lower end of the extension S and at its upper end engaging the shoulder around the under side of the enlargement or head on the upper end of the chuck. The chuck shown in Fig. 2 is a Horse taper'chuck having a tapering central bore with a slot h through its upper end to receive the flattened end of the shank of the drill or other tool to be fitted in it; but it will be understood that any other form of chuck or tool-holder of proper exterior shape and size may be readily substituted for the one shown and that a great variety of chucks may be used with the machine and readily substituted one for another at will by simply unscrewing the sleeve-nut Z". It will also be understood that but for the desirability of providing removable chucks to accommodate tools of different characters the depending extension S of the rotary frame I might be constructed to directly receive the shanks of the tools, and this may be done when desired.

The nut M upon the shaft J at the upper end of the machine heretofore described is shown extendedinto a vertical screw A,upon which is screwed a cylindrical nut F", provided at its upper end with a centering-point G. Near its middle the nut F is provided with an enlargement II, having a polygonal surface upon which is fitted a hand wheel or lever K, by which the nut F may be turned upon the screw A. The screw A and nut F, with its centering-point G and the means for turning it, constitute a force feeding device for the drill, such as is common in machines of this character. The end thrust of the machine when used with the force feeding device is taken by the balls V, fitting between the ring U and the fiange R of the bushing P, heretofore described.

For convenience in holding the machine while being turned it is provided at each side with handles L, consisting of short sections of pipe screwed at their inner ends into bosses N, formed upon the outer sides of the casing A.

In rotary drills of this general character heretofore devised the speed-reducing gearing between the engine-shaft and the chuck or tool-holder driven by it has usually been located at one side of said shaft, thereby producing objectionable side strains in the driving connection. In my machine the power is applied to the rotary cross-head on opposite sides of the engineshaft, and the driving connection between the engine-shaft and tool-holder driven by it is perfectly balanced and all the objections incident to the old arrangement entirely overcome.

Having thus fully described my invention, I claim 1. In an engine, the combination of a rotary frame, a plurality of cylinders carried thereby and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and valves at the outer ends of said cylinders for controlling the admission and exhaust of the motive fluid to and from their outer ends behind their pistons.

2. In an engine, the combination of a rotary frame, a plurality of cylinders pivotally mounted thereon and having their pistonrods connected to a fixed pivot eccentric to the axis of the frame, and means controlled by the oscillations of the cylinders upon their pivotal supports to admit the motive fluid to and exhaust it from the cylinders through said supports.

3. In an engine, the combination of a rotary frame, a plurality of cylinders mounted thereon upon pivots fixed in said frame and having their piston-rods connected to a fixed eccentric or crank pin, said pivots constituting valves and being provided with inlet and exhaust ports alternately opened and closed by the oscillations of the cylinders upon them, to admit the motive fluid to and exhaust it from the cylinders.

4. In an engine, the combination of a rotary frame, a plurality of cylinders pivot-ally mounted thereon at their outer ends and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and inlet and exhaust ports at the outer ends of said cylinders which are opened and closed by the oscillations of the cylinders upon their pivotal supports, to admit the motive fluid to and exhaust it from their outer ends behind their pistons.

5. In an engine, the combination of a rotary frame, a plurality of cylinders pivotally mounted thereon at'their outer ends and having their pistonrods connected to a fixed pivot eccentric to the axis of the frame,and

means for admitting the motive fluid to and exhausting it from the outer ends of the cylinders through their pivotal supports.

6. In an engine, the combination of a rotary frame, a plurality of cylinders pivotally mounted thereon at their outer ends and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and means controlled by the oscillations of the cylinders upon their pivotal supports to admit the motive fluid to and exhaust it from their outer ends through said supports.

7. In an engine, the combination of a rotary frame, a plurality of cylinders pivotally mounted thereon at their outer ends and having their piston-rods. connected to a fixed pivot eccentric to the axis of the frame, and valves within the pivotal supports of the cylinders for controlling the admission and exhaust of the motive fluid to and from the outer ends of the cylinders behind their pistons.

8. In an engine, the combination of a rotary frame, a plurality of cylinders pivotally mounted thereon at their outer ends and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and valves within the pivotal supports of the cylinders for controlling the admission and exhaust of the motive fluid to and from the outer ends of the cylinders behind their pistons, the inlet and exhaust ports of said valves being opened and closed by the oscillations of the cylinders.

9. In an engine, the combination of a rotary frame, a plurality of cylinders mounted at their outer ends upon pivots fixed in said frame and having their piston-rods connected to a fixed eccentric or crank pin, said pivots constituting valves for controlling the admission and exhaust of the motive fluid to and from the outer ends of the cylinders behind their pistons.

10. In an engine, the combination of a rotary frame, a plurality of cylinders mounted at their outer ends upon pivots fixed in said frame and having their piston-rods connected to a fixed eccentric or crank pin, said pivots being provided with inlet and exhaust ports opened and closed by the oscillations of the cylinders upon them, to admit and exhaust the motive fluid to and from the outer ends of the cylinders behind their pistons.

11. In an enginefthe combination of a rotary frame, a plurality of cylinders mounted at their outer ends upon pivots fixed in the rotary frame and having their piston-rods connected to a fixed eccentric or crank pin, each of said pivots consisting of an internallybored post or tube containing a live-air chamher and an exhaust-chamber, and ports intermediate said chambers and the outer end of the piston-chamber in the cylinder and opened and closed by the oscillation of the cylinder, for the purpose described.

12. In an engine, the combination of a rotary frame, a plurality of cylinders mounted at their outer ends upon pivots fixed in the rotary frame and having theirpiston-rods connected to a fixed eccentric or crank pin, each of said pivots being provided with a longitudinal inlet-port and a longitudinal exhaustport, out of line with each other, and the cylinder-head being provided with a cooperating port brought into register with the first-mentioned ports alternately by the oscillations of the cylinder upon the pivot.

13. In an engine, the combination of a rotary frame, a plurality of cylinders mounted at their outer ends upon pivots fixed in the rotary frame and having their piston-rods connected to a fixed eccentric or crank pin, each of said pivots consisting of an internallybored post or tube containing a live-air chamber and an exhaust-chamber, an inlet-port opening into the live-air chamber and an exhaust-port opening into the exhaust-chamber, out of longitudinal line with each other, and the cylinder-head being provided with a cooperating port brought into register with the first-mentioned ports alternately by the oscillation of the cylinder upon the pivot, for the purpose described.

1%. In an engine, the combination of a rotary frame, a plurality of pivots fixed in said frame, a plurality of cylinders having heads at their outer ends provided with sleeves surrounding and fitting said pivots and having their piston-rods connected to a fixed eccentric or crank pin, and inlet and exhaust ports in said pivots and cylinderheads which are opened and closed by the oscillations of the cylinders upon said pivots, for the purpose I described.

15. In an engine, the combination of a rotary frame, a plurality of pivots fixed in said frame and each consisting of an internallybored post or tube having a live-air chamber and an exhaust-chamber, and an inlet and an exhaust port opening into said chambers respectively, and a plurality of cylinders having their piston-rods connected to a fixed eccentric or crank pin having heads at their outer ends provided with sleeves surrounding and fitting said tubular pivots and provided with ports to cooperate with the inlet and exhaust ports of the piyots in the manner and for the purpose described.

16. The combination of the valve R provided with the chambers 13 and B and the ports 0 and O, and a cylinder having a head P provided with a sleeve Q surrounding the valve. R and adapted to oscillate upon the same as a pivot, said head P being provided with the diametrical slot D constituting a port to cooperate with the ports 0 and O of the valve R as the cylinder oscillates upon said valve.

17. The combination of the valve R provided with the chambers B and B and the ports 0 and C, and having'upon its exterior the grooves E and E forming continuations of the ports 0 and C, respectively, and the cylinder having a head P provided with a sleeve Q, s'urroundin g and fitting the valve R, and also having a diametrical slot D adapted to cooperate with the ports and grooves in the valve R in the manner described.

18. In an engine of the character described, the combination of a rotary frame carrying at one end a central hollow shaft and provided with radial passages communicating at their inner ends with the bore of said shaft, a plurality of cylinders carried by said rotary frame, and valves located at the outer ends of the radial passages in said frame for admitting the motive fluid to and exhausting it from the outer ends of the cylinders and causing it to pass, in one direction or the other, through said passages in the rotary frame and the internal bore of the shaft carried thereby.

19. In an engine of the characterdescribed, the combination of a rotary frame carrying at one end a hollow central shaft and provided with radial passages communicating at their inner ends with the bore of said shaft, a pluralityof pivots fixed in said rotary frame at the outer ends of said radial passages and each provided With an inlet and an exhaust passage, one of which communicates with one of the radial passages in the rotary frame, and a plurality of cylinders mounted at their outer ends upon said pivots and provided with ports cooperating with the inlet and exhaust ports of the pi-vots, for the purpose described.

20. In an engine of the character described, the combination of a rotary frame carrying at one end a central hollow shaft and provided with radial passages communicating at their inner ends with the bore of said shaft, a plurality of pivots fixed in said rotary frame at the outer ends of the respective radial passages, and each consisting of a tube provided With an inlet and an exhaust chamber, one of Which chambers communicates with one of the radial passages in the rotary frame, and each pivot being also provided With inlet and exhaust ports communicating with said chambers, respectively, anda plurality of cylinders mounted at their outer ends upon said pivots and provided with ports cooperating with the inlet and exhaust ports of the pivots, for the purpose described.

21. In an engine of the character described, the combination of the rotary frame I carrying the hollow central shaft K and provided with the radial passages 0 communicating at their inner ends with the bore of the shaft K, the tubular pivots R secured in the frame I at the outer ends of the passages 0 and provided with the chambers B and B and with the ports 0 and O, the chambers B communicating with the outer ends of the respective passages 0, and the cylinders provided with heads P having the sleeves Q surrounding and fitting the pivots R, and having also.

the ports D to cooperate with the ports 0 and O of the pivots R as the cylinders oscillate upon the latter.

22. In an engine of the character described, the combination of a rotary frame composed of two opposing plates suitably secured together, one of said plates having a bearing upon a fixed crank-shaft and the other having secured to it a central hollow shaft supported in suitable bearings, and being provided with radial passages communicating at their inner ends with the bore of such shaft, a plurality of pivots secured at their opposite ends in the opposing plates of said rotary frame at the outer ends of the radial passages, and each provided with an inlet and an exhaust port, one of which communicates with the radial passage, and a plurality of cylinders mounted at their outer ends upon said pivots between the opposite plates of the rotary frame and having the inner ends of their piston-rods connected to the eccentricpin of the fixed crank-shaft, and having their heads provided with ports to cooperate with the inlet and exhaust ports of the pivots.

23. I In an engine of the character described, the combination of the fixed crank-shaft J, the rotary frame composed of the plates H and I, the former having a bearing upon the shaft J and the latter having fixed in it the central hollow shaft K and provided with the radial passages o communicating at their inner ends with the bore of said shaft, the tubular valves R secured at their opposite ends in the plates H I at the outer ends of the passages o and each provided with the chambers 13 and B" and the ports 0 and O, the chambers B communicating at their lower ends with the radial passages 0, the cylinders provided with heads P having the sleeves Q surrounding the valves R, and having also the ports D to cooperate with the ports 0 and O of said valves, and the pistons S in said cylinders having their rods T connected at their inner ends to the eccentric-pin L of the fixed crank-shaft J.

24-. In an engine of the character described, the combination of the fixed crank-shaft J, the rotary frame composed of the plates H I,

the former having a bearing upon the shaft J and the latter having fixed in it the central hollow shaft-K and being provided with the.

radial passages ocommunicating at their inner ends with the bore of said shaft, the tubular valves R fixed at their opposite ends in the plates H I at the outer end of the radial passages 0 and each provided with the chambers B and B" and the ports C'and C, said chambers B communicating at their lower ends with the passages 0 by means of circumferential grooves and ports a in-the valve R, the hollow flanged screws Y screwed into the upper ends of the valves R and serving to secure the latter to the plate H without obstructing the entrance to the chambers 13 of the valves, the flanged screws Z screwed into the lower ends of the valves R and serving to secure the latter to the plate I and to close the lower ends of the chambers B, the cylinders provided with heads P having the sleeves Q surrounding the valves R and provided with ports D to cooperate with the ports 0 and O of the valves, and the pistons S Within the cylinders having the inner ends of their rods '1 connected to the eccentric-pin L of the fixed crank-shaft J.

25. In an engine of the character described, the combination of the fixed crank-shaft J provided with the groove d and the hole 9 communicating with said groove, of the rotary cylinder-carrying plate H having the large central opening surrounding the shaft J and carrying the cylinders having their piston-rods connected to the eccentric-pin L of the shaft J, the ring e fitting in said opening and provided with the groove corresponding to the groove d, the balls f fitting in the track formed by the groove d and the groove in the ring 6, the extra ball for closing the passage between the hole g and the groove d in the shaft J, and means for holding said extra ball in place.

26. In an engine of the character described, the combination,with the fixed eccentric pivot L, of the rotary frame carrying the cylinders having their piston rods T provided with straps surrounding said pivot, the rings V fitting within said straps and each having a V- shaped groove upon its inner surface, and the balls IV interposed between said rings and the pivot L and confined in the grooves in the rings.

27. In an engine of the character described, the combination of the rotary plate or frame I having the radial passages 0, and the hollow shaft K secured in said frame with its bore communicating with the passages 0, for the purpose described.

28. In an engine of the character described, the rotaryframe composed of the plates H and I secured together at the outer ends of their respective arms by posts or tubes constituting pivots for the cylinders and valves to control the ad mission and exhaust of the motive fluid to and from the outer ends of the cylinders.

29. In an engine of the character described,

the rotary frame composed of the plates H and I secured together at their outer ends by the posts or tubes constituting pivots for the cylinders and valves for controlling the admission and exhaust of the motive fluid to and from the outer ends of the cylinders, the plate II of said frame having a bearing upon a fixed shaft J, and the plate I thereof having secured in it the hollow shaft K affording the bearing for the latter plate, and being provided with the radial passages 0 communicating at their inner ends with the internal 'bore of the shaft K and at their outer ends with the valve-pivots upon which the cylinders are mounted.

30. The combination of the fixed crankshaft J having the eccentric-pin L, the rotary frame composed of the plates H and I secured together by the posts or tubes R constituting both pivots and valves for the cylinders, the plate H having a bearing upon the fixed shaft .I, and the plate I having secured in it the hollow shaft K affording a bearing for it, and being also provided with the radial passages 0 communicating at their inner ends with the internal bore of the shaft K and at their outer ends with the valves R, the cylinders having the heads P provided with the sleeves Q surrounding the valves R, and the pistons S with- .in said cylinders having their rods '1 connected at their inner ends to the eccentric-pin L of the fixed shaft J.

31. In an engine, the combination of a liveair chamber to which the motive fluid under pressure is admitted, a rotary frame within said chamber, a plurality of cylinders carried by said frame and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and valves controlling the passage of the motive fluid from the live-air chamber to the outer ends of the cylinders and its exhaust therefrom.

32. In an engine, the combination of a liveair chamber to which the motive fluid under pressure is admitted, a rotary frame Within said chamber, a plurality of cylinders carried by said frame and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and valves at the outer ends of the cylinders controlling inlet and exhaust ports for admitting the motive fluid to and exhausting it from the outer ends of the cylinders, said inlet-ports communicating with the interior of the live-air chamber and the exhaust-ports communicating with exhaustpassages in the rotary frame.

33. In an engine, the combination of a liveair chamber to which the motive fluid under pressure is admitted, a rotary frame mounted in saidchamber, a plurality of cylinders pivotally supported upon said frame and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and inlet and exhaust ports opened and closed alternately by the oscillation of the cylinders upon their pivotal supports, to admit the motive fluid to and exhaust it from the outer ends of the cylinders, said inlet-ports communicating with the interior of the live-air chamber and the exhaust -ports communicating with ex haust-passages in the rotary frame.

34:. 'In an engine, the combination of a liveair chamber, a rotary frame mounted in said chamber, a plurality of cylinders pivotally supported upon said frame at their outer ends and having their piston-rods connected to a fixed pivot eccentric to the axis of the frame, and inlet and exhaust ports at the outer ends of the cylinders for admitting the motive fluid to and exhausting it from the outer ends of alternately by the oscillations of the cylinders upon their pivotal supports to admit the motive fluid to and exhaust it from the outer ends of the cylinders, said inlet-ports communicating with the interior of the live-air chamber and said exhaust-ports communicating with an exhaustpassage at the axis of the rotary frame.

36. In an engine, the combination of a liveair chamber, a rotary frame mounted therein and provided with a plurality of radial exhaust-passages communicating at their inner ends with an exhaust-passage in an axial shaft carried by the rotary frame and extending through the wall of the live-air chamber, a plurality of cylinders carried by the rotary frame and having their piston-rods connected to a fixed pivot eccentric to the axis of said frame, and valves controlling inlet and ex haust ports for admitting the motive fluid to and exhausting it from the outer ends of the cylinders, said inlet-ports communicating with the interior of the live-air chamber and said exhaust-ports communicating with the radial exhaust-passages in the rotary frame.

.37. In an engine, the combination of a liveair chamber, a rotaryframe mounted therein and provided with a plurality of radial exhaust-passages communicating at their inner ends with an exhaust-passage in an axial shaft carried by the rotary frame and extending through the wall of the live-air chamber, a plurality of cylinders pivotally supported upon the rotary frame at the outer ends of its radial exhaust-passages and having their piston-rods connected to a fixed pivot eccentric to the axis of said frame, and inlet and exhaust ports opened and closed alternately by the oscillations of the cylinders upon their pivotal supports, to admit motive fluid to and exhaust it, from the outer ends of the cylinders, said inlet-ports communicating with the interior of the live-air chamber and said ex-l haust-ports communicating with the radial exhaust-passages in the rotary frame.

38. In an engine, the combination of a liveair chamber, a rotary frame mounted therein and provided with a plurality of radial exhaust-passages communicating at their inner ends with an exhaust-passage in a central shaft carried by the frame and extending through the wall of the live-air chamber, a plurality of pivots fixed in the rotary frame at the outer ends of its radial exhaust-passages and each provided with an exhaust to a fixed pivot eccentric to. the axis of the frame, and provided with ports alternately placed in communication with the live-air and exhaust chambers of the pivots by the oscillations of the cylinders, to admit the motive fluid to and exhaust it from the outer ends of the cylinders.

39. In an engine, the combination of a liveair chamber, a rotary frame mounted therein and provided with a plurality of radial exhaust-passages communicating at their inner ends with an exhaust-passage in a central shaft carried by the frame and extending through the wall of the live-air chamber, a plurality of tubular pivots fixed in the rotary frame at the outer ends of its radial exhaustpassages and each having its internal bore separated into an exhaust-chamber communicating with one of the radial exhaust-passages and a live-air chamber communicating with the interior of the main live-air chamber, and each provided with an inlet-port opening through its Wall into its live'a-ir chamber and an exhaust-port opening through its wall into its exhaust-chamber, and a plurality of cylinders mounted at their outer ends upon said tubular pivots and having their piston-rods connected to a fixed pivot eccentric to the axis of the rotary frame, the heads of said cylinders being provided with ports cooperating with the inlet and exhaust ports of the tubular pivots at the oscillations of the cylinders, to admit the motive fluid to and exhaust it from the outer ends of the cylinders.

40. In an engine, the combination of a liveair chamber, a crank-shaft fixed centrally in one end of the wall of said chamber and provided with an eccentric crank-pin, a rotary frame mounted in said chamber and having a bearing at one end upon said fixed crankshaft and provided at its opposite end with an axial shaft extending through the wall of the liveair chamber and containing an exhaust-passage communicating with radial exhaust-passages in the rotary frame, a plurality of cylinders pivotally supported upon the rotary frame at the outer ends of said radial exhaust-passages and having their piston-rods connected to the eccentric pin of the fixed crank-shaft, and inlet and exhaust ports opened and closed alternately by the oscillations of the' cylinders upon their pivotal supports, to admit the motive fluid to and exhaust it from the outer ends of the cylinders, said inlet-ports communicating with the liveair chamber and said exhaust-ports comm unicating with the radial exhaust-passages in the rotary frame.

41. The combination of a chamber to which motive fluid under pressure is admitted, a shaft or member extending through the wall of said chamber and rotating relatively thereto, and provided with a projecting annular shoulder or flange, and a washer surrounding said shaft and seated partly upon said shoulder and partly upon the wall of said chamber and held to its seat by the pressure of the motive fluid, to form an air-tight joint between the relatively-moving parts.

. 42. The combination of the live-air cham-. ber, the rotary shaft K extending through the wall 0 thereof and provided with the sleeve it having the projecting annular flange, and the washer m surrounding the shaft K and seated partly upon the wall 0 of the live-air chamber and partly upon the flange of the sleeve is, and held to its seat by the pressure of the motive fluid, for the purpose described.

43. The combination of the live-air chamber, the rotary shaft K extending through the wall C thereof, the sleeve surrounding said shaft and having the projecting annular flange, the ring j located in an annular seat in the wall 0 around the shaft K and sleeve is, the balls Z interposed between the sleeve 70 and ring j, the washer on surrounding the shaft K and seated partly upon the wall 0 of the live-air chamber and partly upon the flange of the sleeve k, and held to its seat by the pressure of the motive fluid, for the purpose described.

44. The combination of the casing A, the crank-shaft J secured in fixed position in the cap B of said casing and having the eccentric crank-pin L, the rotary frame within the easing A, composed of the plate H having the bearing upon the shaft J, and the plate I having secured to it the hollow shaft K, extending through and having a bearing in the lower end wall of diaphragm O of the casing, said plate I being provided with the radial passages 0 communicating at their inner ends with the internal bore of the shaft K, the tubular valves R secured at their opposite ends in the plates 11 and I of the rotary frame and each provided with a chamber B communicating with the interior of the casing A and with a chamber B communicating with one of the radial passages 0 in the plate I, and with a port 0 opening into the chamber B and a port 0" opening into the chamber 13,-

the cylinders having their heads P provided with sleeves Q surrounding the valves R and with ports D to cooperate with the ports 0 and C of the Valve, and thepistons S within the cylinders having the inner ends of their rods T provided withstraps surrounding and having a bearing upon the pin L of the fixed crank-shaft J.

45. In a rotary pneumatic drill the combination, withan engine embodying a rotary frame and a plurality of cylinders mounted upon and driving the same, and the axial shaft driven thereby, of a fixed circular rack concentric to said shaft, a pinion fast upon the shaft, a rotary chuck-holdin g member carrying two gears 011 opposite sides of the pinion and meshing therewith and with the fixed circular rack, and means for removably securing different styles of chucks in said oh not:- holding member.

46. In a rotary pneumatic drill, the combination, with the central shaft driven by the motor or engine, of a fixed circular rackconcentric to said shaft, a pinion fast upon the shaft, a rotary chuck-holding member carry: ing two gears on opposite sides of the pinion and meshing therewith and with the fixed circular rack, said chuck-holding member being provided with a depending extension concentric with its axis, adapted to receive within it and hold from independent rotation a chuck or tool holder provided with an enlargement or head at its upper end, and a nut fitting within the lower end of said extension to removably hold the chuck in place.

47. In a rotary pneumatic drill, the combination, with the central shaft driven by the motor or engine, of a fixed circular rack concentric to said shaft, a pinion fast upon the shaft, a rotary chuck-holding member carrying two gears on opposite sides of the pinion and meshing therewith and with the fixed circular rack, said chuck-holding member being provided with a cylindrical depending extension concentric with its axis and adapted to receive within it a cylindrical chuck or tool holder provided with an enlargement or head at its upper end, a keyway and key intermediate said chuck and cylindrical extension for preventing independent rotation of them, and a nut fitting in the lower end of said cylindrical extension and cooperating with the enlargement or head of the chuck to hold the latter in place.

48. In a rotary pneumatic drill, the combination, with the central shaft driven by the motor or engine, of a fixed circular rack concentric to said shaft, a pinion fast upon said shaft, a rotary chuck-holding member carrying two gears on opposite sides of said pinion and meshing therewith and with the fixed circular rack, said chuck-holdin g member being provided with a cylindrical depending extension, a bushing or ring surrounding said cylindrical extension and fixed in the casing of the machine, and provided with an internal annular flange or ring whose upper and lower surfaces afford tracks for ball-bearings, aseries of balls interposed between the upper side of said flange and the under side of the rotary chuck-holdin g member, a nut screwed upon the cylindrical extension of said member beneath the flange of the fixed ring, and a second series of balls confined between said nut and the under side of said flange to receive the end thrust of the machine.

49. In a rotary pneumatic drill, the combination, with the engine-shaft K, of the fixed circular rack Q concentric to said shaft, the pinion L fast upon said shaft, the rotary frame or cross-head N having the cylindrical depending extension S, the gears M M mounted upon the cross-head N at opposite sides of the pinion L and meshing with said pinion and with the rack Q, the bushing P fixed in the casing D around said extension S and provided with the internal flange or ring Q, the ring T fitting around the extension S at the under side of the frame N, the

balls R interposed between said ring and the upper side of the flange Q of the bushing P, the flanged ring or not U screwed upon the extension S and having a beveled upper edge fitting Within the bushing P, and the balls V confined between the same and the under sideof the flange Q of the fixed bushing P, for the purpose described.

50. In a rotary pneumatic drill, the combination, with the engine-shaft K, of a fixed circular rack Q concentric to said shaft, the pinion L fast upon the shaft, the rotary frame or cross-head N having the cylindrical depending extension S exteriorly and interiorly threaded at or near its lower end and provided with an interior projection Z near its upper end adapted to cooperate with a vertical groove or keyway in the chuck to be inserted within said extension, the gears M M carried by the frame N on opposite sides of the pinion L and meshing with said pinion and with the rack Q, the bushing P fixed in a circular opening around the extension S and provided with the internal flange or ring Q, the ring T fitting around the extension S at the under side of the frame N, the balls R interposed between said ring and the upper surface of the flange Q of the fixed bushing P, the flanged ring or nut U screwed upon the exterior of the extension S and having a beveled upper edge fitting within the bushing P, the balls V interposed between the upper edge of said .ring and the under surface of the flange Q, the lock-nut IV screwed upon the extension S below the ring U, to hold the latter in place, and the nut Z screwed into the lower end of the extension S to hold the removable chuck in place.

51. In a rotary pneumatic drill, the combination of the casing A having the upper cap B and the removable lower cap D and sepa rated into two chambers by the diaphragm C, the engine located in the upper chamber and driving the central shaft K projecting through the diaphragm 0 into the lower chamber, the fixed circular rack Q secured in the cap D concentric to the shaft 'K, the pinion L fast upon said shaft, the rotary chuck-holding member N having the depending cylindrical tutti extension S journaled in the lower cap D", and the gears M M mounted upon said rotary member on opposite sides of the pinion L and meshing with said pinion and With the fixed circular rack Q".

52. The herein described cylinder, composed of the Wrought-steel shell 0 and the head P made of cast-bronze and provided with a circular groove in which is fitted the end of the shell 0, the outer Wall of said groove being spun over upon the outer surface of the shell to form an air-tight joint and furnish the sole means for securing the shell and head together, substantially as described.

53. The herein-described cylinder, composed of the cylindrical shell 0 and the head P, the shell 0 being thickened at one end or provided with a beveled flange, as at a, and the head P being provided with a circular groove 2) in which is fitted the thickened or flanged end of the shell 0, and the outer Wall of which groove is spun down over the thickened end of the shell 0, substantially as described.

54. The combination of the tubular valve R, the cylinder composed of the cylindrical shell 0 and head P, the latter being provided with the sleeve Q surrounding the valve R and with the diametrical port D cooperating with the ports in the valve R, and having the circular groove 1) in which is fitted the end of the shell 0 and the outer Wall of which groove is spun over upon the outer surface of said shell, and the cup-shaped piston S fitting within the shell 0 and having the piston T rigidly secured to it atone end and con-- nected at its opposite end to the crank-pin L, substantially as described.

JOSEPH BOYER.

Witnesses: Y

E. G. LANGHORNE, E. WENG R.