US2508315A

US2508315A - Hot gas motor with phase changer

Info

Publication number: US2508315A
Application number: US613945A
Authority: US
Inventors: Franciscus Lambertus Va Weenen; Stigter Willem Hendrik
Original assignee: Hartford National Bank and Trust Co
Current assignee: Hartford National Bank and Trust Co
Priority date: 1943-04-06
Filing date: 1945-08-31
Publication date: 1950-05-16
Anticipated expiration: 1967-05-16

Description

3 1950 F. L. VA'N WEENEN ET AL 2,508,315

HOT GAS MOTOR WITH PHASE /CHANGER Filed Aug. 31, 1945 mmm LAMBERTUJ m1 WEENEN& mum HENDRIK JTIGTER ATTOR/Vf' Y Patented May 16, 1950 11:.

HOT GAS MOTOR WITH PHASECH-ANGER Francisco's Lambertus van Ween n and Willem" Hendrik Stig ter; Eindhoven; Netherlands, as signers to: Hartford National Bank & Trust Company, Hartford, Conni as trustee An ueation rmgust 31, 19215,. Serial No. 613',945

This invention pertains to a hot-gas engine, and moreparticulanly to a device for controlling th indicated power bymodifyihg the phase angle between the Working piston v and the displa'cer piston;

we; known that by modifying the phase oflthe niovementsof'theworking piston and'of the dis placer piston; itispossible to regulate-the course the pressure in the cycle and consequently ailso' the 'power of themotorrs. A=known deVioefr regulating this phase angle: consists of separate drives: for the piston andforthe displacer, in which event the-displacer is driven bytwo dinerentl y arranged-eccentrics, which are connected the rod of! the displacer through the interm'ediary of a linkbeam; which construction is also found piston steam engines which" com prise a slide valve as the steam distributingmember. Such a: linkconstruction lias th'e drawback thattherma'ss which is tobe m'oved to and fro large: which drawback is especially prevalent inenginesarunning at a high speed;

Axpr i ma'ry object of this-invention is"to--o've'r-- comektheabove problemfurther object of this inventionis to rovide-im'eans for altering: the power output or a hot' gas'rengine.

still further object of this ihi'Ient'iOIiiS-tO prO vide azphase: changer device for piston type engines; A

' Other objects and advantages-of thisinvention will be:apparentas the descriptiomproceeds';here inafter.

'lh'eidrawing- 'showsa preferred embodimentof theipresentiinvention Accordingizto the present invention; use is mad'e otfanother distinctly different" device froth those mentionediand known for 'modifying the phase between the: working piston and-the displacer piston Generally speaking, this device is" char acterized'in that a separate crank shaft is present for the piston as wella's'for the'displac'er, which crank shafts are coupled with one another via gear wheels by means of an intermediate shaftwhich is slidable in the direction of the center-line of this shaft. Considering each of the gear wheels. on .thesaid intermediate shaft, it is noted that"th'equotient of the gear wheel diameter'and the angle between the direction of'pthe teeth. and' the center-line of the intermediate sl'i'ait is' not -equalto that of the other gear wheel, for iuse'ismade-ofgear wheels withoblique or'fielieal teeththere occurs simultaneouslywith thersli'dingtmovement of this intermediate shaft ofiitherlatter...v Thiserotation isiflqlial-"tb the angular displacement of'th'e' some 01 appn cation on the gear wheel efthegear wheel mesiie ing therewith. Theangle' of displac'eme'nt-of this point ofapplication is directly propoitional to the angle which forms the teeth it-h the-'eeiite line of the intermediate shaft inversely proportional to the gear wheel diaihet'er. If for the-two gears on the intermediate shaft these quotients are equal, onlythe-ihterinediateshatt is consequently rotated upon displacement; the shafts coupled therewithremaining at rest dur ing this rotar-ymotiom Iftlie quotientsareuii equal, as in the case" according tothe invention, the angular displacement on the" one seat wheel is consequently, with a determined displacement; not-equal to' that on the other gear" wheel; and therefor the twocrank shafts rotaterelat-i vely to one another and the phase angle' betweenthe two cranks Varies.

A hot-gas engine is generally constructed such manner that with adeterminedphase angle between the piston'an'd the dis'pl ac'erj whichangl-e may be, for example, 90", the maximum indicated power is" obtained. A larger phase angle im possible-from a construet-io'rialpoinfi of v ew cause in' thiscase the pis'ton and the displ er would butt" e einstone 1 another as'inalier phase angle is, however, always-possible If the phase angle becomes zero; the indisated power is no; If the phase angle b'ecornes n-egativejg the motor rotatesin the opposite direction; The' negative value may" riseto the same height as themaximum positiv'evalue, that is, 90"; as described hereinafter; sothat-it-is again 'st'iinpossihleforthe piston and the displacer tobutt against oiiean other. The device according tethe invention'is preferably" constructed in seen mariner-"that the phase angle lzi'ei'iireen the? positive" and negative maximum-flvaluesis *varia'hleso" thatth'e described construction mayserve-not only forthe control of the power but alsofor the reversal oftliedl rection of rotation ofthejengine: q I

Owing-t'o the fact that the displace'r? pisto'r'i can be displaced with respect t'oth'ewoi'kingpi's ton, it is possible'to-startthe engine by meanso'f this construction.

The invention will be eiiplained more fiillywith reference tothe accompanying' drawingi which represents, by way of exampleone embodiment thereof; Y

The drawing represents: only-"the parts of a hot-gas engine which are essential:fbr ah understa'ndingof this inventionzt A workin'g pistbn ll and a displacer piston" I0beingi-aligned pistoi i means: arewconnected zto separate 'crank 'sha itsi and [3 respectively through the intermediary of various cranks and connecting rods. Piston means II is coupled to the crank shaft l2 by a Y or wishbone shaped connecting rod means I l'. A piston rod Ill attached to the piston means It] is coupled to the crankshaft I3 through the intermediary of offset pitman means l3. The phase between the piston II and the displacer I9 consequently depends on the phase angle between the two crank shafts l2 and I3. Since a modification of this phase angle entails a change in the course of the pressure of the cycle, the indicated power of the engine may be varied by adjusting this phase angle.

These crank shafts are coupled with one another by means of an intermediate shaft [6 through the intermediary of screw wheels or gear means. Since in a hot-gas engine the speeds of the piston and of the displacer are equal, the ratio of transmission via this intermediate shaft and these gear wheels is 1:1. However, in order to be able to modify the indicated power, it must be possible to modif the phase angle relationship between the crankshafts l2 and 53. This is effected by displacing the intermediate shaft it, which is coupled for this purpose with a lever 29. The intermediate shaft has mounted on it two screw or gear wheels or gear means l5 and iii of which the former meshes with a gear wheel 14 on the crankshaft l2 and the latter with a gear wheel I! on the crank shaft i3. The gear wheels l5 and it are constructed in such manner that upon displacement of the shaft l6 along its own axial length the shafts l2 and it perform unequal rotary motions so that the phase between these shafts varies. This consequently implies that upon displacement of the shaft [6 the point of application between the gear wheels l7 and I8 is displaced through another angle than the point of application between the gear wheels It and I5. With screw wheels or gears the displacement of the point of application or original contact depends on the pitch of the teeth and on the diameter of the gear wheel, and this in such manner that the angular displacement is greater according as the pitch angle is larger (by pitch angle is meant the angle formed between the teeth and the center-line of the shaft), this angular displacement being, with the same pitch angle, inversely proportional to the gear wheel diameter. Upon displacement in the direction of the shaft, gear wheels whose quotients of pitch angle and gear wheel diameter are equal may consequently undergo equal angle displacements,

although the gear wheel diameters are unequal.

intermediate shaft, a maximum variation of the phase angle between the crankshafts of the piston and of the displacer isobtained, if on the two gear wheels the angles formed between the teeth and the axis of the gear wheel are opposite. The numerical values of these quotients are therefore preferably made equal in order that two equal gear wheels milled in opposite directions may suifice. On the ground of these latter considerations the diameters of the gear wheels I5 and I8 and therefore also those of the gear wheels l4 and I! are all made equal to one another.

What we claim is:

1. In a hot-gas engine, a device for controlling its indicated power by modifying the phase angle between its piston and displacer comprising a crank shaft of the piston, a crank shaft of the displacer, parallel gear means fixed to each of said shafts, an intermediate shaft, gear wheels parallel with said gear means coupled to said intermediate shaft, said gear wheels being coupled to said gear means respectively, said gear wheels being so proportioned that the quotient of one gear wheel diameter and the angle between its teeth and center-line of the intermediate shaft is not equal to that of another gear wheel.

2. A device as claimed in claim 1 wherein said intermediate shaft is axially movable with respect to said crankshafts to such an extent that the phase angle varies from a positive maximum value to a negative maximum value.

3. A device as claimed in claim 1 wherein said quotients are of equal but of opposite values.

4. A phase changing device for a hot-gas engine comprising a piston crankshaft, a separate displacer crankshaft parallel to the first, gear means fixed to said shafts respectively, an intermediate shaft parallel to said shafts, spaced gear wheels coupled to said intermediate shaft, said gear Wheels being so proportioned that the quotient of one gear wheel diameter and the angle between its teeth and the center-line of said intermediate shaft is not equal to that of another gear wheel whereby variou longitudinal movements of the same into mesh with said respective crankshaft gear means cause phase angle differences between said crankshafts, and means for moving said intermediate shaft along it own longitudinal axis in two directions.

5. A phase changer device as claimed in claim 4 wherein said intermediate shaft is axially movable with respect to said two crankshafts to such an extent that said phase angle vary from positive values to negative values.

6. A device as described comprising aligned piston means, connecting rod means coupled to said means, a first one of said rod means being movable within one of said piston means, parallel crankshaft means coupled to said connecting rod means, offset pitman means, one of said crank shaft means being coupled to said ofiset pitman means, an intermediate shaft substantially interposed between said crankshaft means, gear Wheel means fixed to said respective crankshaft means and intermediate shaft for coupling said piston means, and means for moving said intermediate shaft with gear wheel means thereon axially whereby the phase angle between said piston means is changed.

7. A device as claimed in claim 6 wherein the structural relationship of the gear wheel means on said intermediate shaft is such that the quotient of the gear wheel diameter and the angle of one gear wheel means between its teeth and center-line of said intermediate shaft i not equal to that of another gear wheel means.

FRANCISCUS LAMBERTUS VAN WEENEN. WILLEM HENDRIK STIGTER.

REFERENCES CITED The following references are of record in th file of this patent:

UNITED STATES PATENTS Number Name Date 537,517 Anderson Apr. 16, 1895 684,927 De Ferranti Oct. 22, 1901- 805,562 Lamplough Nov. 28, 1905 921,649 Peache et al May 11, 1909 2,073,550 Crakes et al Mar. 9, 1937 2,245,075 Mingle June 10, 1941