US1252458A - Power reverse-gear. - Google Patents

Description

S H. LEWIS.

POWER REVERSE GEAR. APPLICATION FILED OCT. 18,-i9l5.

Patented Jan. 8,1918;

3 SHEETS-SHEET I.

N 31 I uc 11 fo t C v 150/7106! JLLewis,

3 SHEETS-SHEET 3.

Patented Jan 8, 19181 S. H. LEWIS. "POWER REVERSE GEA'R. APPLICATION HLED OCT. [8. I915.

Nh N To all whom it may concern:

Be it known that I, SAMUEL H. LEWIS, a citizen of the United States, residing at Richmond, in the county of Henrico and State of Virginia, have-invented certain new and useful Improvements in Power Reverse- Gears, of which the following is a specifica tion. a

My invention relates to improvements in fluid pressure operated apparatus for operating or shiftin the valve gear of steam engines, particu arly railway locomotives, while not necessarily restricted to this use.

An important object of this invention is to simplyify apparatus of the above men tioned character, and particularly to obviate the necessity of providing positive locking means to revent undesired movement the piston in the power cylinder.

Another object of this invention is to 'provide means to prevent waste of fluid pressure at the exhaust port of the operat ing valve.

A 'further object of the invention is to provide means for resistingundesired m0vement of the piston in the power cylinder by opposing such undesired movement with an increase of pressure on the side of the piston in the direction in which it starts to inove and a decrease of pressure on the opposite side of the piston.

Other ob'ects and advantages of the invention will be apparent durlng the course of the. following description.

In the accompanying drawings forming a part of this specification and in which like, numerals are employed to designate like parts throughout the same,

Figure 1 "1s, a side fievation of apparatus embo ing my inven on, showing the same up ie to a railway locomotive, 2 is a' detail side elevation of a pivot oint,

-3 of Fig. 2

Fig. 4 is an. d elevation of theapparatus Fig. 5 is a central vertical longitudinal sectional view through the power cylinder,

embodied'in the apparatus,

Fig. 6 is a transverse sectional view taken online 6---6ofFig.5,

Fig. 7 is an elevation of the inner side of the apparatus,

Specification of Letters Patent.

F 3 is a detail sectional view taken on UNITED STATES PATENT ()FFIOE.

SAMUEL H. LEWIS, 0F RICHMOND, VIRGINIA.

POWER REVERSE-GEAR.

Patented Jan. 8, 1918.

Application filed October 18, 1915. Serial No. 66,487.

Fig. 8 is a side elevation of the valve casl ig. 9 is a sectional view taken on line 99 of Fig. 8,

Fig. 10 is a horizontal sectional view taken on line 10-10 of Fig. 9,

' {fig 11 is an elevation of a rotatable valve, an

Fig. 12 is a diagrammatic view of ports formed in the valve casing.

In the drawings, wherein for the purpose oi illustration is shown a preferred embodiment of my invention the. numeral 10 designates the boiler of a railway locomotive, equipped with the cab 11, as is customary. The numeral 12 designates a preferably horizontally arranged power cylinder, preferably disposed beneath the boiler 10 forwardly of and near the cab 11, while'the cylinder may be attached to any other suitable ofithe locomotive. ibis c linder is rlgi y sebured to'the boiler 10 y any suitable means.

As more clearly shown" in Fig. 5, a piston 13 is disposed to reciprocate Within the cylinder 12, and is rigldly/fionneoted with a preferably tubular piston rod 14, the rear end of which has screw-threaded engagement with aplug 14, as shown.

As clearl shown in Fig. 5, this piston rod prefera ly but not necessarily has portions 15 and 16, of difierent diameters, the portion 15 having the smaller diameter.

he forward reduced portion 15 of this.

piston rod operates througlh a forward stuffing box 17, carried by a sad 18, while the rear lar eportion 16 of the piston rod operates t rough a rear stufiing box 19, carried by a head 20. The function of .havin 'the portions 15 and 16 of the piston rod 0 The piston 13 is provided upon its pe? riphery and at a point equidistantly spaced from its ends with an annular groove 21',

receiving an inner metallic packing ring 22 and outer' acking rings '23 preferably formed of 'l 'iibber or the like. Upon its periphery and at its'ends, the piston. 18 1s rovided with annular grooves 24, receiving interfitting metallic rings 25', L-shaped in cross-section, as shown. I have found that this combination of packing rings prevents the leakage of pressure between the piston and the cylinder 12, in a highly satisfactor manner.

The tbrward end of the rod 14, is pivotally connected, as shown at 26, with a pit man or link 27, pivotally connected, as shown at 28, with a vertical crank or arm 29, rigidl mounted upon a transverse lift or rock shaft 30. Each endof the lift or rock shaft 30 has a. horizontal arm 31, rigidly connected therewith, which is connected with the vertically movable link (not shown) of the valve gear. It is to be understood that the invention is in no sense. restrieted to operating any particular type of valve gear as it is adapted for use. in connection with various types.

Rigidly connected with the forward end of the piston rod 14 is :1 depending arn: or crank 32, having its lower end pivotally connected with a link 33, pivotally connected with the lower end of a pretl rably vertically swinging lever Bl. 'lhe \Iertically swinging lever 34 (see Figs. and 3). isarovided between its ends with zh longitu inal opening 35, receiving a flat lug or extension 36, formed integral with a pivot element or bolt 37. This pivot element or bolt is rotatably mounted in. an opening- 38 extending transversely through the end of a bracket 39. The flat lug or extension is provided with a screw-threaded longitudinal opening 40, receiving an adjusting screw 41. The opening 35 is longer than the lug, 36, and the adjusting screw 4.1 engages the end walls of this opening. It is obvious that by turning the adjustin screw 41 it will. be shifted longitudinally with respect. to the lug 3G and will hold thewlever 3i at a different position with respect thereto, whereby the pivot point of this lever may be adjusted up and down. Formed upon the In receiving anut 43, haying a washer 4-}, preferably interposed between the nut and the lever 34. The function of adjusting the pivot of the lever 34 is'to regulate the operation of the piston with respect to returning the eontrolllng valve to the neutral position.

Pivotally connected with the upper end of the lever 34:, as shown at 45, is a. preferably longitudinally adjustable or extensible reach rod46, as shown.

The numeral 47 designates a valve structure as a whole, comprising a casing or casting 48, having a Hat face 49 and rovided with an inlet port 50, communicating with a pipe 51, which leads to asonree of pres sure, such as a compressed air storage tank (not shown). This inlet port communicates with an inlet port 52, passing throp'gh an 36 is a screw threaded. extension 42,

annular flange 58, formed upon the casing 51, as shown. Arranged upon opposite sides of the inlet port are pairs of ports 54, 55; 56, 57, which lead into pipes 58 and 59, discharging into the opposite ends of the cylinder 1.2. The pairs of ports 54 and 55 have their upper ends discharging into a pair of non-con'nnunieatingspaced segmental surface ports 0 and 61 res| ectively; while the pairs of pets 56 and 57 have their upper ends leading into noncommunieating segmental surface ports (52 and 63 respectively. Each pair of ports at, 55 or so, 57 lead into a chauilmr 53, as shown. At its lower end, the. chamber 53 has screwthreaded engagiunent with a tube 5+, extending upwardly therein, as shown. The upper end of this tube serves as a guide for a check ball valve, normally closing the end of the port (:5 or 57, and this ball valve is normally held seated by a spring 56 as shown. The tube H has aperlures 58, arranged beneath the ball valve. The tube :i-l is internally screw-threeded to receive nlH. ol the pipes, leading to the power cylimlrr. The numeral. til designates an exhaust port, arranged centrally with respect to the segmental surface ports, as shown.

Mounted to rotate within the flange in slidahle ronlact with the face 49 is a valve on, hai'ingits inner side provided with a. sur faeeigrmfe or port (30, the. inner end of which is 1!] permanent rgistration with the exhaust port (H \\'liilc. --i'ls outer end is adapt ed to he alternately moved'into registration with the segmental ports (30 and 62. The. valve (35 is provided in its lower portion with a transverse port. or opening 67, ar- .rang l. between the segmental grooves 61 and n;5.-:ind when the valve 65 is in the normal position the opening 67 preferably has its ends arranged in line ioline relation with and a head (it), which closes this chamber.

The pressure from the port 50 is thus clrculated upon the top of the valve 65, and serves to retain it securely seated.

ill)

The valve (15 is provided with a post 69',

for turning it, which post is rectangular in cross-section and. adapted to fit within an opening 7 ().Iforn1ed in a head 71 of a stud .72. rigidly connected with a. pinion 73. The 'head 71 is adapted to contact with a washer 74, and a. compressible, coil spring 75 is arranged between the post 69' and the end wall of the opening 70, thus serving to hold-the valve upon its seat and. the head 71 in. con-' tact with the ring or washer 74 for preventing leakage.

The head 69 is provided with a flange 70,

' bination lever extends upwardly for pivotal E at slightly larf ;.piston 13, a

connection with a controlling lever 84:, b means of'a pin 85 or the like. This contro' ling) lever carries the-ring 77, which is -pretera ly formed .integral therewith and pivotally mounted upon the flange 53. Ri dly connected with the upper portion 0 the combination lever 83, by means of bolts 86 or the like, is a toothedsegment or gear 87, en aging the pinion 73, for turning it.

he control lever 84 operates in proximity to a stationary toothed'quadrant 88, rigidly secured to the upper ends of stationary arms 89 formed integral with the casing l8. The lever 84is provided with latch means 90, to cooperate with the toothed uadrant to lock the lever in adjustment at tie desired position. The operation lows:

When the control lever 84 is in the normal or neutral position, the rotary valve is in the normal or neutral position, whereby the ends ofithe admission port 67' are arranged substantially in line to line relation with the inner or lower ends of the surface ports 61 and 63. There is then a passage of fluid ,pressure from the port 67 into the lower segmental ports 61 and 63, which pressure is conducted throu h the pipes 58 and 59 to the opposite en s of the outer cylinder 12, upon opposite sides of the piston 13, thus equalizing the pressure "upon such opposite sides and tending to hold the piston against movement. B iaving'the portion 15-of the rod 14 of smal er diameter than the portion 16, this equalpres'sure will oplerate upon a er surface, u on t e side of the jac'ent the 're uced portion 15 of the'rod 14, and this increased surfaee is sufli cient tqvovercome the tendency that the elements of the valve gear have to move downwardly by gravity. While .the pressure .is thus calpable' of being constantly supplied into the opposite ends of the cylinder 12, by

virtue'pf theline to line position of the ends of theport 6'7 with the ends of the port 63,

the pressure within the opposite ends of the cylinder 12 cannot circulate in a reverse di- ,rection, through the pipes 58 and 59, to the source of pressure, as the upwardly seating valves 55 close the ends of the ports 55,

of the apparatus idah fol-' while the ports 60 and 62 which are exhaust ports, are closed, when the valve 65 is in the neutral position. It is thus apparent that pressure, which passes into the op osite ends of the cylinder 12, is entrapped t erein and any perceptible improper movement of the piston, will rapidly increase ressure, thus serving to positively. hold t 9 piston 13 against any extensive improper movement. For illustration, if the iston 13 should move from its adjusted position, with a pressure of one hundred pounds er square inch on its opposite sides, for t e d stance of three-sixteenth of an inch, there will be de veloped a resistance of approximately one hundred and fifty pounds to further undesired travel of the iston, due tothe compression and expansion of the fluid pressure on its op'osite sides, thus rendering it im possible or the piston to move to any con-' siderable extent or sufficiently to cause perceptible operation of the parts of the apparatus.

hen it is desired to shift the valve gear to drive the locomotive forwardl the con trol lever 80 is swung forward y. When this is done, the upper end of the combination lever 83 is swung forwardly, carrying with it the segmental gear 87, whereby the pinion '73 is carried clockwise. This clock wise movement of the pinion 73 turns the valve 65 clockwise, whereb the upper end of the port 66 is moved into registration with lei segmental groove 62 and the port 67 is w red i to registration with the port 61. It is thu apparent that pressure will pass through pipe 51, port 52, chamber 68, port 67, port 61, port 55, pipe--58, into the left. end of the cy inder 12, while ressure will exhaust from the opposite en of the cylinder through pipe 59, port 54, port 62,

ort 56, and port (i l, to the atmosphere.

he piston 13 is then moved forwardly whereby the rod" 14 and associated elements operate the valve Igear to drive the Incometive forwardly, pon this forward move ment of the rod 14, the depending. arm 32 is moved forwardly swinging the lower end of the lever 34 forwardly and its upper end rearwardly. The rearward movement of the upper end of the lever 34: is transmitted to the reach rod 46, and by it to the combination lever 83. The lever 84 being locked in the new position by the latch means 90, the combination lever 83 will turn upon the in 85 as a pivot and when its lower en is swung rearwartily the segmental gear 87 is swung rearwar where y it turns the pin; ion 72 counter-clockwise, returningthe valve 65 to the neutral position. When the valve 65.is returnedto its neutral position, the pressure equalizes upon opposite sides of the piston 13. By this means the extent of movement of the piston in either direction is always proportional to the movement of the control lever in the same direction. When the control lever 84 is swung rearwardly the reverse of this operation takes place as is thought to be obvious from the foregoing description.

It is to be understood that the form of my invention herewith shown and described is to be taken as a preferred example of the same, and that various chan es in the shape, size, and arrangement 0 parts may be resorted-to without departing from the spirit of the invention or the scope of the subjoinecl claims.

l-Iaving thus described the invention, what I claim is:

'1. in apparatus of the character described: a cylinder; a piston mounted to move within the cylinder; a valve ear op erated by the movement of the piston; a valve seat having two separate surface supply ports and two separate surface exhaust )orts arran ed about an exhaust OJGlllIl which communicates with the atmosphere; chambers having ports leading to surface supply ports and ports leadin o the surface exhaust ports; a movable valve having a surface port in permanent communication with the exhaust openihg of the valve seat and adapted to be alternately moved into communication with the exhaust surface ports and a pressure supply port .normally in line to line relation with the surface supply )orts to permit of the. simul taneous suppy of pressure through both surface supply ports-and to be moved in one direction 'for covering one surface supply port and opening the other surface supply port; pipes having communication with the chambers and with the opposite ends of the cylinder; and means to supply pressure to the pressure supply port of the movable valve.

.5. In apparatus of the character described; a cylinder; a piston mounted. to move within the cylinder; a valve gear operated by the movement of the piston; a valve seat having two separate surface supplyports and two separate surface exhaust ports arranged about an exhaust opening which communicates with the atmosphere; chambers having orts leading-to the surface supply ports an ports leading to the surface exhaust ports; a movable valve having a surface port in permanent communication with the exhaust opening of the valve seat and adapted to be alternately moved into communication with the exhaust surface ports and a pressure supply port normally in line to line relation with the surface supply ports to permit of the simultaneous supply of pressure through both surface supp y ports and to be moved in. one direction for covering one surface supply port and opening the other surface supply port; pipes having communication with the chambers and \xi ththe opposite ends of the cylinder; check ial ves arranged within the chambers and adapted to close the ports which lead to the surface supply ports; andmeans' to supply pressure to'the pressure supply port of the movable valve.

ln testimony whereof I affix my signature in presence of two witnesses.

SAMUEL H. LEWIS. Witnesses:

James L. CRAWFORD, C. L. PARKER.

Images