US 2378874 A
Description (OCR text may contain errors)
June 19, 1945.
R. s. TROTT ENGINE MOUNTING Filed OCT 15, 1941 2 Sheets-Sheet 1 June 19, 1945. R. s. TROTT ENGINE MOUNTING Filed Och-15, 1941 2 Sheets-Sheet 2 INVENTORN @MZVMZZ Patented une-19, 1945 mgr OFFICE ENGINE Morm'rmo Rolland: s. Trott, Denver, 0010.; memoimm executrix of said Rolland S. Trott, deceased I Application October 15, 1941, Serial No. 415,114
7 Claims. My invention relates to engine mountings for automobile engines and the like, and more especially to an engine mounting in which the engine vibrational forces will be completely prevented from being transmitted-to the frame and body of the automobile.
Many engine mountings with this same general aim have been invented in the past in the attempt to solve this long-standing problem, and in order to make clear what my present invention provides over and above the prior art on this problem. it will be well to set forth here abrief record of some of the interesting steps in engine mounting development up to thepr'esent time.
Some of. the first attempts were built upon the rough idea of providing cushioning movements for the engine unit; but these first attempts proved that when cushioning movements, were provided the result-could easily be much worse thanwhen solid or rigid mountings .were used. This was apparently because improper cushioning move ents made the engine, during its'jcushione ing ovements, act almost like a hammer.
In these previous constructions, the mountings themselves have three distinct functions, which three functions are as follows:- 1st, therubber or other resilient construction of the mountings ,acted to roughly locate the axis of oscillation;
2nd, resiliently resisted the oscillation "of the engine unit; and 3rd, provided transverse cushfact that the automobile has a revolving flywheel.
But, in previous patents, the engine unit is to be oscillated, not revolved, and it is impossible to oscillate" the engine unit and thereby check it for oscillation in balance and finally provide oscillation in perfect balance. That is, there are no machines, nor devices whereby oscillation in perfect balance may be provided to compare with the means for providing rotation in perfect balance.
In this invention, to accomplish the 1st of the three functions above mentioned, that is, the exact location of the axis of oscillation so that the oscillation may take place in perfect balance, I
provide two metallic mountings, upon which the engine unit may be mounted and revolvedllke a or propellers, as any mechanic verseg in such ioningv for the resultantor other shock or .trans verse forces.
In this inveeition, the three functions are performed by thr separate and independent means.
That is, I provide constructions in w ch the location of the axis .of oscillation is not 0 butit may be most accurately checked and rected for real perfection and this in no interferes with the proper performance of the 2nd and 3rd functions, whichare taken care of by separate and independent means. i
That is, the 2nd and 3rd functions, the resilient resistance of the torque cushioning" oscillation, and the resilient cushioning of transverse forces, are in this present invention, taken care of by separate and independent mama-whereby each i may be designed and constructed forperfect permatters willrunderstand.
The 2nd of the three functionsabove mentioned, is performed and provided in my present invention by engine reaction absorbing means connected from the-engine unitto one of the axles as ,clearlyset forth in Trott No. 1,834,879 and No. 1,986,701; that is, the torque forces are transmitted'to one of the axles by any proper resilient connection, and thus these torque forces are not transmitted in any way to the frame or body of the "automobile... Or the torque forces may be transmitted to the frame of the vehicle by a separate and compound construction in which the ordinary or normal torque forces of the evenly .running engine are taken care of completely by a an ordinary or normal torque structure and excessive torque forces, such as in starting, or missed explosions; or dropping the clutch in quickly formance of its function without consideration of the other functionand its performance. A flywheel may be mounted and revolved and checked for perfect balance, as any mechanic will understand, and there are even machines and devices by which any revolving part may be accurately checked and balanced. Because of this, no one in a modern automobile is even conscious of the when the engine is running at high speed or from any other causes resulting in an additional or excessive amount of oscillation, are taken care of by an excess torque structure that is inoperative during ordinary'or normal running of the engine.
but that automatically "becomes operative when the oscillation becomes greater than the ordinary or normal oscillation.
Thus by this compound torque structure both thenormal and the excess torque forces can be taken care of as perfectly as far as shock or vibration on the frame is concerned. as if the torque forces were transmitted direct'to one of the axles as mentioned above, and'not to the V frame at all.
The 3rd of the three function above mentioned, that of cushioning tansverse forces, may now be provided without any consideration whatever for the resilient resistance tothe oscillation of the engine unit, or the proper location of the axis of oscillation.
It is true that some of the prior patents 'show one metallic mounting, or some other feature of this separated-function construction,
but none of them shows a construction in which the engine unit could be mounted and revolved in balance like a flywheel or a propeller so that its balance could be checked and improved upo until perfect.
As an illustration; in the Trott and Lee-patents, since the' rubber mountings must locate the axis of oscillation they transmit some or all of the torque reaction and cushion the transverse forces,
a hardness rubber about of an inch thick and perhaps two-inches .wide is required to; A, prevent the axis of oscillation from wandering too far from the proper, in-balance location; B, prevent the. amplitude of the oscillation from becoming too great; and C, cushion or attempt to properly cushion the transverse. forces.
But in this present invention, the metal mountings and the separate torque connection of either type, permit perfect cushioning to be provided in the rubber mountings.
As an illustration; in a circular ring of rubber surrounding and supporting a metal mounting,
or to the cushioning properties of the mounting may be employed.
' Thus my present invention can be so built that not the least sensation can be transmitted to the frame or body of the automobile, even in a four cylinder automobile.
There may be other Trott patents bearing on this new engine mounting but perhaps not necessary thereto. In any case, though these issued Trott patents, some of them, are used in this invention, they are not of themselves novel parts hereof.
For the novelty of this invention consists in providing two metallic mountings upon which the engine unit may be mounted to be completely revolved at high speed, if desired, and checked for as perfect balance as a flywheel, and the combination of these two metallic mountings with a resilient torque connection from the engine unit to one of the axles, or to the frame through proper compound resilient means,
and the further combination of rubber mountings, (supporting the metallic mountings) that would be too soft, flexible or resilient if they also had to locate the axis of oscillation and resiliently resist the torque cushioning oscillation of the engine unit.
In other words we can now see that the improverfnents in engine mountings have come about first, as a result of balanced torque cushioning oscillation, and that further improvements have been made as a result of improved control of the location of the weight of the engine unit during its torque cushioning oscillation.
This control of the location of the, axis of oscillation and the three stepsin this development were, first, self-centering, or self location of the front of the axis of oscillation by the engine unit itself, while the rear of the axis of oscillation was roughly located on rubber; second, approximate location of the axis of oscillation by two rubber or resilient mountings roughly located, the exact location of the axis being through self -centering at the two rubber mountings; and third, the exact location of the axis in thisapplication by two metallic mountings so that theengine unit may be as accurately balanced in its oscillatory movements as is a flywheel in its revolution. To this third step is then added the torque connection to an axle, or through proper compound resilient torque means to the frame, thus removing the torque forces from the frame and body; and since the rubber mountings then do not have to either locate the axis nor resist nor limit the amount of the I torque cushioning oscillation, the rubber mountings supporting the metallic'mountings, may be made resilient enough to perfectly cushion all transverse shocks orforces so that actual perfection in the prevention of the transmission of section of an engine unit equipped with my present engine mounting. Figure 2 is afragmentary view from the rear showing the longitudinal locator and the compound torque connection between the engine unit and the frame.
Figure 3 is a fragmentary section on the line 3--3 of Figure l. v
Figure 4 is a fragmentary view from above, of the rear portion of the engine unit and of the compound torque connection between the engine unit and the frame. I
Figure 5 is a fragmentaryfront view in partial section on the line 5-55 of Figure l, of the front of the engine unit, and showing my floating pedestal.
Figure 6 is a fragmentary view somewhat similar to Figure 4 but showing a modified form of construction of the torque resisting rubbers.
In the front construction (Figures 1 and 5), the stud bolt I is fixed in the engine cylinder 2 at about theeproper locationwhi'ch in combination with the rear mounting will mount the engine unit to oscillate substantially in balance.
Th metal trunnion 3 has the central hole 3A Because of the clearance between the stud bolt I and the bore 3A of the trunnion 3, the; trunnion 3 may be moved transversely with respect to the cylinder 2 as required in the balanc nfl, operations, to so locate the trunnion 3 on the cylinder 2 that the engine unit may rotate on its front When - and rear mountings in perfect balance.
such proper location is obtained, the nut 6 is set tightly and locked in place by acotter pin, 6A.
But, before this is done the bushing 1, with the a rubber cushion 8 and the floating pedestal 8 are placed on the trunnion 3: then the washer- I, nut l and cotter pin 8A are installed.
Either the trunnion 3 or the bushing I, or both should be made of some properly self-oiling or selfflubricating material, or proper provision should be made for either oil or grease lubrication. a
That is, the bushing 1 should at all times be free to oscillate on the trunnion 3, while held against endwise movement by the flange 3B and the washer I.
a It will be seen that this construction provides a metal to metal bearing which may be moved with respectv to the cylinder 2 till exactly the right location of perfect balance of the engine unit is obtained, and when this perfect location is obtained and properly locked, it will be permanent.
Though the construction illustrated carries out these requirements, naturally any othercombination of details that will provide the same results, may be employed if desired.
For, these exact details of construction are not what are desired so much as a proper metal bear- .ing construction which may be moved with respect to the engine unit, as indicated by proper testing equipment, till absolutely perfect balance of the engine unit is obtained, and which when obtained may be locked permanently in the proper position.
The spherical rubber cushion 8 provides cushioning of the metal bearing.
As shown, the rubber is properly vulcanized or otherwise attached to the bushing I and the pedestal 9, but any proper construction other than shown may be used if desired; in fact the member I may even be of metal, even though for some installations this will not be as perfect as the construction shown, and it will require some slight detail changes as any mechanic will understand.
For perfection of balancing, individual checking of each unit may be made, but where the design and the finishing are such as to make all units substantially identical, it is possible to obtain absolutely perfect balance of one unit by careful checking and movement of the front trunnion on the cylinder, and then attempt to make all subsequent units exactly the same as the one that was'checked and balanced.
In many types, sizesand kinds of installations this may be satisfactory, even though perhaps every, say, tenth unit is individually checked But, of course, for real perfection in every unit, each unit should be individually balanced, 'just like each flywheel is individually balanced in automobiles.
The section shown in Figure 1 is taken on the line Il--l of Figure 5. The pedestal 9 II. II.
The rubbers III are vulcanized or otherwise properly attached to the plates II, II, which plates are in turn bolted by the bolts I to the pedestal 9 and the brackets I 2 respectively.
The brackets 12, may be riveted, bolted, welded,
' or otherwise properly attached to the automobile frame cross member II, or some other part of the automobile frame, or the brackets if may issupported on the rubbers be integrally formed to perform their function as a part of the frame of the automobile.
It will be noted that the rubbers l0 carry the front of the engine unit in shear, which provides more delicacy of resilience than if the rubber were in direct compression.
The cross sectional area of the rubbers lli may be proportioned to provide the strength desired in the cushioned support of the pedestal l.
Though the mounting of the pedestal s on the frame as shown in Figure 5,. may be constructed to provide all the resilience and the results required, any other combination of details that will provide satisfactory resilience and results may be used if desired. i i
In the particular construction shown, it will be noted that'the rubber 8 acts in compression and therubbers In, act in shear, so that the different periodicities of the rubber in compression and the rubber in shear will act in series to break up any periodic vibrations of the engine unit under any circumstances whatever.
For ease in making the'last delicate touches in balancing the engine unit, certain off-center where, may be screwed, riveted, brazed, welded or otherwise properly attached to the engine, or
may, even be made integral therewith. These weights may be reduced by a drill, a file, or any other proper means, an amount indicated by whatever balancing device is employed. Or the proper amount of weight may be properly attached to the engine unit as indicated. by the balancing device employed.
The propeller shaft If, the universal joint II and the brake drum l9 are properly connected to the transmission tail shaft 20.
The shaft 20 is carried in the rear of the transmission case 2| by the bearing 22.
And the bearing 22 is held in place by the excess torque plate 23, which is held in place against I the transmission 2| by the bolts 24. i
The transmission case 2| is finished as at 26 to act as a rear mounting for the engine unit, which bearing face 25 is concentric with the shaft 20,and this bearing face 25 acts as the rear mounting, for the engine unit.
The rear mounting support 26,fits the bearing The mounting support 26 is provided with mounting lugs 21. i
The rubbers III are vulcanized or otherwise properly attached: to the plates II, are attached by the ,bolts I4, or loss 2'! and the. brackets [2' V The brackets I2 may be iveted or welded or otherwise properly attac d to thefram 28, or
, the frame may be so d signed, and constructed.
as to be formed with the brackets integral there-'- with, or at least the frame should; be formed in such'a way that the plates ll/may be easily and properly attached thereto. It will be seen that this completed rear mounting provides a bearing near the universal joint which permits, oscillation of $19 engine unit excess torque,
about an axis that is permanently located with respect to the engine unit, so that "once the 'engine unit is mounted to permit its oscillation in perfect balance, such condition will be permanent. s It will be noted that the rear of the engine unit is supported on rubber that acts in shear, and that the in-shear construction is the same as used to support the pedestal 9 at the front of the engine unit.
However, this identity of construction need not be followed unless desired.
What is important is to mount both ends of the engine unit very resiliently, which resilient mountings support metallic mountings which are so located that they support the engine unit so it will oscillate in perfect balance.
With the engine unit thus mounted in perfect balance-and supported on resilient supports, it could berevolved at high speed and it would vibrate the automobile no more than do present flywheels of automobiles, for, when the work of balancing is being done, the entire engine unit will be in the same condition, as far as weight is concerned, as when it is actually driving the car.
That is, the water jacket will be full of water, the crankcase will be supplied with oil, and the transmission will be supplied with grease.
Of course in actual operation the engine does let us say, four times the ordinary or normal torque of the engine unit. And this excess.
torque would mean that the amount of oscilla tion of the engine unit would he, say, four times the amount of oscillation-produced by the nor mal torque reaction. And'this excess torque reaction should be'taken care of by excess torque reaction structure ofsome kind.
The e cess torque rubbers'lllx see Figs. 4 and 6 are v canized or otherwise properly attachedtothe plates X, which in turn are properly attached by the bolts "X or otherwise, to the brackets and to the excess torque plate. and these brackets 30 may be, in turn, secured by-bolts I! or otherwise to the automobile crossmember 28 as shown in Fig. 2. i I
It will be noted that the excess torque rubbers 10X are located from theaxisAA at a radius that is roughly thrice theradius of the normal torque rubbers I 0. 'Thatis, the excess torque rubbers' have three times the leverageithat the normal torque rubbers have; a Itshould also be notedthatztheexcess torque rubbers have approximately 1 the cross sectional area that the normal torque rubbers have.
So, taking, into consideration both the radius not revolve, it oscillates, but if it can revolve in perfect balance, it must also oscillate in perfect balance. v But the resistance which prevents the engine unit from revolving and forces it to oscillate,
. must be resilient enough so that it will not proprovide a compound torque connection as follows; Y
The transmission case 2| is provided with brackets 29. The plates Il, are bolted by.the bolts ll, to the brackets 29 or otherwise properly attached thereto, and to the brackets ll'also. I
The rubbers III are vulcanized or otherwise I properly attached to the plates II, and they act as the ordinary or normal torque connections. The rubbers l0 and the plates H are shown to be similar to the rubbers 'III and plates ll of the front and rear mountings. But, whether the rubbers I0 are actually the same as the rubbers l0 depends upon conditions, since it isnot necessary that they are alike.
For, the rubbers 10' should be at such a radius from the axis of oscillation A .-A, and of such cross sectional area and of suchsoftness and resilience, that under steady even running of the engine unit the amount of oscillationis such as to perfectly cushion the torque jerks or impulses so that no engine vibration at all is transmitted from the engine unit to' the automobile.
But, when an explosion misses, or when the clutch is dropped in quickly when the engine is running at high speed, the torque transmitted at least for an instant, may easily amount to.
and the area of the section of the rubber, the
excess torque rubbers areiourtimes as strong in resistance to oscillation as the normal torque rubbers, and henceprovlde four timesthe ,resistance to the oscillation of the engine unit as is provided by the normal torque rubbers.
Let us suppose that under normal even running conditions the oscillatorymovement at the normal torque rubbers III is, say, onesixteenth of an inch, then at thrice the radius, that is, at s the excess torque rubbers 10X, this oscillatory movement will be three times as great, or three sixteenths of, an inch.v
It will be noted in Figure 4 that the excess torque rubbers It}; are shown to be compressed,
so that'the rubbers IBX bulge and are thicker in the middle than at the ends.
That is, the excess torque rubbers IOX, they I are mounted andshown in Figure 4, have been compressed three sixteenths of an inch orsllght- 1y more, which is why they are shown to be bulged L I atthemiddle. w
Now since the oscillation at the excess torque rubbers IOX under normal steady running condir,
tions, as stated above, is three sixteenthsfloi an inch, 'or the same amount that the rubbers IX are compressed, this'normaloscillation will take place without any appreciable resistance being offered by the torque rubbers NIX.- I 1 In other words the weak resistance of the nor-.-v mal torque rubberslll' alone will resist the oscillation during normal steady running, condi-g 3 tions. During the smallest oscillations the rubbers I0 will act purely in shear, and as the amplitude of the oscillationincreases the-rubbers It will act more and more in tension. But-when through missed explosions or sudden dropping in of theclutch when theengine is running at high speed, or from any otherreason, fthe torque is very greatly increased, then the amount oioscillation will naturally tend to be increased in proportion totheincrease in the amount oi torque reaction.
,But, with this H when theoscillation increases above the normal torque cushioning oscillatlom, the ,excess torque rubbers will come into action at once resistance which is, say, our times the of the normal torque rubbers. I
with their r s ta c fcomp ound. torque connection,
That. is, when the oscillation becomes great enough so that the excess torque rubbers are no longer compressed, they will be at their proper uncompressed length and ready to resist any oscillationthat' is greater in amount. When this normal torque reaction, then the excess torque her. That is, the clutch release force puts 'a longitudinal pressure on the engine unit. i
- In case the engine unit is movably or flexibly mounted on the frame, this longitudinal clutch release force tends to move the engine unit longitudinally on the frame, and this longitudinal movement tends to move the clutch release shaft lever end longitudinally and thereby affect the clutch engagement.
As a result of this, clutch chatter sometimes develops when engaging the clutch in flexibly mounted engine units, especially when the transrubbers may be placed at a greater radius from the axis A-A, or may have greater cross sectional area, or both; and the amount of normal compression of the excess torque rubbers may also be changed to meet any conditions desired. Change of the normal length of both the normal and the excess rubbers will naturally change their resistance characteristics and this may be resorted to if needed.
Thus by my compounding torque connections, as soft a resistance as desired may be selected for the normal torque rubbers, and as much increase in resistance as desired may be provided against increased oscillation dueto excess torque conditions. in such matters, will now be able to provide exactly the compounding of the torque connection that is required for the best operation in any type or kind of installation.
Thus, in my invention, I have eliminated any forces or vibrations which might be due to imperfeet or unbalanced oscillation, by perfect balancing of the engine unit on its two metallic mountings; I have eliminated the transmission of resultant or other transverse forces to the frame of the vehicle by rubber mountings in shear and by series use of rubber in compression and in shear; and I have provided torque resistance that may be designed and constructed to provide all the oscillatlon that is required for the perfect cushion- It is thought that any mechanic, versed ing of the torque forces under 'steady running conditions, while providing a compounded resistance that will limit the maximum oscillation of the engine unit under excessive torque conditions, to little more than the normal steady running oscillation.
In case the engine mounting is used in an airplane engine, not only does all the above apply,
. but there are also other considerations which should be here explained.-
In an airplane engine, the propeller absorbsthe operation of the clutch and to sudden brake action, are resiliently resisted. In an automobile engine the clutch operation mechanism is such as to release the clutch b transmitting the clutch release force from the clutch pedal, which is mounted on the frame, to the lever on the clutch release shaft, whidh is carried by theengine unit, through a longitudinally extending rod or memmission is in reverse, as well as at other times.
And this clutch chatter may even develop with this present engine mounting construction. In some cases this clutch chatter may be overcome by a construction such as shown in Figure 6,
in which the brackets 29 are lengthened to form the lengthened brackets 29', and the excess torque rubbers l ox are then attached to the brackets 29' V and to the brackets 30.
In this construction it will be noted that the normal torque rubbers III" are in tension as indicated by the reduced section of the rubbers l0"; and this tension of the rubbers Ill" may be made such as to just balance the effect of the compression of the excess torque rubbers lllX, so that the endwise tendency to move the engine unit by the rubbers l0" and IX will be balanced.
One cure for the clutch chatter is to mount the clutch pedal shaft, or a clutch operating shaft (operated by the clutch pedal) revolvably on the frame and then connect the pedal shaft or the clutch operating shaft and the clutch release element or shaft by connecting means which at each end provides universal movement and provides at least at one end of the connection between the clutch pedal and the clutch release shaft or element, some slight transverse free movement.
This permits free movement of the engine unit with respect to the clutch pedal on the frame,
while still permitting the clutch pedal to disengage the clutch while the engine .unit is moving.
mechanism extending between the frame and the engine unit and having universal movement with respect to the frame and with respect to the engine unit, respectively, while permitting all bodily movementsof the clutch release shaft or clutch release mechanism as it is moved by the force cushioning and other movements of the engine uni The above construction is covered in the patant to TIOtt, NO. 2,040,035, but any other construction which will operate the clutch without such operation being substantially aifected by :ine'engine movements, may be employed, if deed. i
But, in any case, whether for an automobile or for an airplane, and whether the endwise pressure on the engine unit of the normal torque rubbers and of the excess torque rubbers oppose each other as in the Figure 6 construction, or both operate to put pressure in the same direction, as in the Figure a construction, I favor the use of my locator or locator brace 3|, as shown in Figures 1, 2, and 4.
It will be seen that the frame member I3 is curved and bent upward to pass over the propeller shaft I1. 1
The locator brace 3| is bent at right angles torque plate 23 or to some other part of'the engine unit and to the frame member l3 or some other part of the frame, by the bolts 32, or the locator 3| is otherwise properly attached to the engine unit and to the frame.
The locator 3| rigidly locates the engine unit longitudinally, whether in an automobile or in an airplane.
In an airplane the locator takes the thrust of the propeller, and in an automobile it resists endwise forces due to clutch operation and inertia forces due to the sudden application of the brakes and the resulting tendency of the engine unit to move forward.
The 90 degree bending of the locator 3| at each end provides what amounts to two horizontal axes H, H, and two vertical axes V, V. These four axes combine to provide a locator which has in effect a universal joint at each end thereof. Considering the very slight amount of transverse movement betweenthe two ends of the locator due to the transverse movements of the engine unit, the locator provides exactly the same movements that it would provide if actual universal joints were built into the locator. That is, all transverse movements of the engine unit required for the perfect cushioning of all forces to prevent their being transmitted to the frame, as well as the oscillatory movements of the engine unit, will be permitted by this locator withthese built-in universal joints, whose universal and oscillatory movements are obtained by the springing of the material of the locator.
Though an automobile engine and an airplane engine have many marked differences, in so far as this engine mounting is concerned they 'may be considered, in a way, actually identical- That is, one end of either engine unit has a permanently located mounting, and the other mounting is to be located by use of proper testing apparatus of whatever kind used.
In the automobile engine the permanently located mounting is adjacent the universal joint; that is, the permanently located mounting is at the power take ofl end of the engine unit and the other end of the engine unit is to be mounted on an engine mounting whose location is arrived at by the use of proper testing apparatus.
In the airplane engine the permanently located mounting is adjacent the propeller; that is, the permanently located mounting is at the ,power take off end of the engine unit, just as in the automobile engine, and the other end of the engine unit is to be mounted on an engine mountinertia force produced when the brakes are violently applied when the automobile is moving at high speed. So, the locator in the automobile installation, the specially constructed locator will permit all transverse or oscillatory movements of the engine unit in properly cushioning all forces to prevent their transmission to the framework of automobile or plane, while still positively holding the engine unit against free longitudinal movement with respect to the framework of either the automobile or the plane.
In'both the automobile and the airplane type mountings, either or both metallic mountings may be supported on single mountings with rubber in shear or in compression, or on shear and compression rubber mountings in series.
In both types of mountings, the normal torque rubbers may operate mainly in shear, but also in tension, after passing the center, and the excess torque rubbers may operate in shear during normal operation but mainly in tension when the oscillation is greater than normal.
In the automobile engine there may be different forms such as the upright four cylinder, the six, the straight eight, the V eight and the V twelve.
In the airplane engine there may be the single row radial, the double row radial,the pancake or opposed, the V, the H and the X, as all mechanics versed in such matters understand.
Though the drawings of this application show only an upright form of in-line engine, any mechanic will understand that this present engine mounting may be applied to any of the above mentioned forms of automobile or airplane engmes.
In the automobile typeof engine the rear mounting will be spaced from the cylinder portion by the shell of the transmission case.
In the airplane type of engine, the rear mounting may, if desired, be spaced from the cylinder portion by a shell somewhat similar to the trans mission case of the automobile type of engine' unit, or a framework of tubes or other skeleton construction may be used in place of the shell to space the rear mounting from the cylinder portion of the engine unit.
Any mechanic versed in these matters will readily appreciate these and other mechanical equivalents which. may be employed in the different forms and types of engine units.
But, in all of these diiferent engine units there are certain essentials that will appear, whichmay be in part listed as follows:
The use of revolution of the engine unit on two metallic mountings to obtain mounting locations engine is behind the engine so it will be put in tension when the above stated inertia force is applied.
The greatest endwi se force tending to move the engine unit longitudinally in an airplane is the thrust force of the propeller, and possibly in some cases the inertia force when landing and due to the contact of the landing wheels with the ground, and tending to move the engine unit forward with respect to the plane.
So, the locator in the plane is placed at the rear of the engine unit where it will be in tension when either the thrust or the inertia force is applied.
And in either the automobile or the airplane that will permit such revolution in perfect balance and thereby insure .that the perfect balance, once obtained, will be continual and permanent.
The use of rubber in shear or in compression, or the use of rubber in shear in series with rubber in compression, to mount either or both of the two metallic mountings;
The use of rubber in shear and in tension to resiliently oppose normal oscillation of the engine unit.
The use of rubber normally compressed in a direction extending longitudinally of the engine unit to provide excess torque resistance once the oscillation at that point becomes great enough a .to permit the compressed excess torque rubber means to reach its normal un-compressed length. (Double opposed excess torque rubbers may be used, if desired, to neutralize their longitudinal pull on the engine unit.)
The location of the engine unit longitudinally by a locator element permitting all transverse and oscillatory movements by the spring of the aaraan material of the locator element, and this locator combined with a flexibly mounted engine unit and longitudinally active normal and excess torque rubbers.
These above methods, or principles or con-' structions may be used in my engine mounting in any type, kind or form of engine.
With all the above explanation, it is thought that any mechanic versed in the art, will be able to provide the results desired'in any installation whether in an automobile or an airplane and of whatever engine form, by the proper location of the two metallic mountings, by their proper resilient support, and by the proper selection of the size and location and mounting of the normal and excess torque rubbers, and by a locator of properly selected proportions and -locations. Having now described my invention, what I claim as new and desire to protect by Letters Patent, is as follows: 1. In an engine mounting in which the engine unit is allowed to have resisted oscillation to cushion the torque impulses, normal torque resisting means including rubber, joining the engine unit and its support located at a normal torque resisting radius from the axis of oscillation, and having normal torque resisting crossseptional areas; and excess torque resisting means including rubber joining the engine unit and its support at a greater radius and of greater sectional area than said normal torque resisting rubber, said excess torque resisting rubber comtransversely and oscillatory while resisting lon gitudinal movement of the engine unit. l i
3. In an engine unit tor mounting an engine mounting on a framework, one metallic pivotal mounting immovable with respect to the engine,
unit, and a longitudinally spaced metallic mounting movable with respect to the engine unit whereby the proper location of said movable mounting will mountthe engine unit in. perfect balance on said two mountings, said metallic mountings being supported on the framework by rubber, and locator means between the engine unit and its support permitting quite freely movements of the engine unit both transversely and oscillatory while resisting longitudinal movement of the en ine unit.
4. Means for mounting an engine unit in perfeet balance on two mountings, an immovable mounting, on a movable mounting means for changing the location of said movable mounting with respect to said engine unit until a location is arrived at whereby the engine unit may be mounted in perfect balance on said two mountings, a torque absorbing rubbjer plate, .an. excess torque absorbing rubber plate, and means for making the excess torque rubber inactive during the normal torque operation by the compression of the excess torque rubber a predetermined oscillatory movements by the spring of the ma- 2. In an engine mounting in which the engine I unit is allowed to oscillate to cushion and absorb the torque impulses, normal torque resisting means including rubber joining the engine unit and its support located at a normal torque resisting radius from the axis of oscillation, and
having normal torque resisting cross sectional terial of which the locator is composed. I
6.- The combination of cushioned metallic mountings, an engine unit carried thereby, one mounting which is not adjustable, a stud bolt secured to the engine unit and extending through the other mounting, a trunnion in the mounting and surrounding the stud bolt, clearance space being provided between the trunnion and bolt, and means for locating and securing the trunnion with respect to the engine unit to attain perfect balance of the latter.
"I. The combination of a vehicle, an engine unit, at least two metallic mountings for the unit and a torque cushioning rubber in shear, a torque rubber compressed to make it inoperative fora predetermined amplitude of oscillation, after which it becomes active.
.ROLLAND S. TRO'I'I.