US 2549768 A
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Description (OCR text may contain errors)
April 24, 1951 D. 1'. BRADLEY VIBRATION MOUNTING Filed Dec. 8, 1945 rl/Iii IN V EN TOR.
DAN 7 'EHDLEY BY Patented Apr. 24, 1951 VIBRATION MOUNTING Dan T. Bradley, Shaker Heights, Ohio, assigner,
by mesne assignments, to Company, Cleveland, Ohio,
Harris Products a corporation of Application December 8, 1945, Serial No. 633,597
This invention relates to vibration absorbing devices for mounting instruments, radio apparatus and various other devices and equipment, and, as one oi its objects, aims to provide an improved and simplied vibration absorbing device of this kind.
Another object of the invention is to provide an improved vibration absorbing device of this character, having a resiliently yieldable portion in the form of a cantilever member made of rubber or rubber-like material.
A further object of the present invention is to provide an improved vibration absorbing device of this character, in which the cantilever member is flexible in a plurality of different directions and may have different degrees of flexibility for such different directions.
Still another object of the present invention is to provide an improved vibration absorbing device in the form of a simple bracket adapted to be economically manufactured and installed and in which a resilient arm forming the cantilever member projects from the attaching portion or base at any desired angle and has means adjacent its outer end for connection with the load or object to be supported.
A further object is to provide an'improved vibration absorbing device of the character mentioned, in which novel stop means is employed for controlling the extent and rate of deflection of the resilient load-carrying arm.
It is also an object of this invention to provide a vibration absorbing means of such character that a plurality of these resilient cantilever members or bracket devices may be employed and disposed so that the load or object will be supported thereby or suspended between the cantilever members or bracket devices and substantially in the plane of the center of mass.
The invention can be further briefly summarized as consisting in certain novel combinations and arrangements of parts hereinafter described and particularly set out in the appended claims.
In the accompanying sheet of drawings,
Fig. 1 is a side elevation showing one form of the vibration absorbing device of the present invention.
Fig. 2' is an end elevation of the device.
Fig. 3 is an elevational view showing an installation utilizing a plurality of the improved vibration absorbing devices.
Fig. 4 is a plan viewl of the same installation.
Fig. 5 is a partial sectional plan view taken on line 5--5 of Fig. 3 and showing one way of con- 2 necting the load to the resilient arm of vice.
Fig. 6 is a sectional view similar to Fig. 5 but showing an alternate form oi load connection.
Fig. 7 is a partial elevational view showing an installation similar to Fig. 3 but in which a modiiied form of vibration absorbing devceis employed.
Fig. 8 is side elevation showing another form f the invention, and
Fig. 9 is a similar View of still another form.
In the embodiment of the invention illustrated in Figs. l and 2 the improved vibration absorbing device il! is shown as comprising an attaching portion or base I I and a resilient arm or cantilever member I2 connected to such base and projecting outwardly therefrom. The arm I2 is provided adjacent its outer end with an opening or sleeve I3 extending therethrough and intended to be used for connecting therewith the load or device to be supported.
The base I I is here shown as comprising a substantially flat metal plate having openings I4 therethrough which accommodate screws or other fastening members by which the base can be connected with an available support. The base II can be of any appropriate size and shape and is'here shown as being rectangular in form.
The resilient arm I2 is preferably made of rubber or rubber-like material and for this purpose either natural or synthetic rubber can be used, the material preferably being a soft'vulcanized rubber of the required composition and stiffness so that the arm will have predetermined rate of deflection and load-carrying characteristics. The resilient arm I2 may be of any desired cross-sectional shape and has a length and cross-sectional area which areappropriate for the load to be carried and the space available to accommodate the vibration absorbing device. In this Vinstance the arm I2 is shown as having a substantially square cross-sectional shape and as having a somewhat converging taper in a direction away from the base II.
the de- It is an important characteristic of the vibration absorbing device ID that the resilient arm' I2 constitutes a cantilevermember which projects outwardly from the base II and is adapted to receive the applied load at or adjacent its free outer end. In the embodiment of the invention.
illustrated in Fig. 1 the resilient arm I2 extends upwardly as well as laterally from the base IIA in its free or unloaded condition so that when a predetermined static load is applied the arm will ybe deilected downwardly to a fully loaded 3 position extending substantially horizontally or at right angles to the base II as indicated in broken lines in Fig. l. However, the arm I2 may, in its unloaded state, project horizontally, or downwardly, as shown in Figs. 8 and 9, respectively, the exact arrangement of the arm being determined by the load, deflection and vibrationabsorbingrequirements of the particular application.
'Ihe resilient arm I2, while in its loaded or deflected condition, is iiexible in a pluralityof different directions relative to the base Il for absorbing the shocks and vibrations which would otherwise be transmitted from the base II to the device being supported, or vice versa. Assuming Y that the arm is in its loaded or broken line position of Fig. 1 it will be seen that vibratory movements of the load upwardly and downwardly in a substantially vertical direction will cause corresponding fleXings or movements of the arm upwardly and downwardly from the broken line position. Movements of the load in a lateral direction, that is, .crosswise of the base II in a substantially horizontal plane will cause corresponding sidewise iiexings or movements of the arm. Likewise, movements of .the load in a substantially horizontal Vplane toward and from the base II will cause deection of the arm toward or away from the lbase but the resistance to deiiection will be much greater because of the endwise compression of the arm. These eXings of the resilient arm I2 in one or more of the directions just mentioned by the applied forces enable the arm to absorb and cushion various shocks and vibrations which would otherwise be transmitted to or from the device being supported.
The above-mentioned outwardly converging taper for the cantilever arm is also an important characteristic because it gives the arm a progressively varying cross-.section which causes a progressively increasing resistance build-up in the arm when a shock load is applied to its outer end such that the greater thedeflection produced by the shock load, the greater will be the resistance build-up. It therefore follows that lthe tapered characteristic gives the arm the ability to resist deflection from shock loads with .a resistance valuewhich increases substantially in proportion to the magnitude of such shock loads.
From the foregoing it will be seen that the cross-section, length and relative inclination Yof the resilient arm I2 can be selected -so that the rate of deiiection of the arm in the three directions mentioned above Awill meet the requirements of the application. This is an important advantage because for certain kinds of v.service where the installation is subject to shock forces in certain directions, aswell as to vibrations, it is desirable that the resilient arm have the required resistance to flexing in the direction necessary lto counteract these shock forces. For example, a piece of apparatus mounted on a railway car is subject to more severe shocks longitudinally of the car than it is in either a vertical or transverse direction due to the effects of coupling cars together and jerks caused by the locomotive or the action of the brakes. Thus in Fig. 3, if the side elevation be assumed to be longitudinally of the car, it is obvious that `the severe shocks referred to would subject the arms I2 to longitudinal compression and Vthereby absorb the shocks. The arching ofthe arms I2 would have the effect of increasing their eXibility in compression thus Venhancing'their cushioning action.
In the vibration absorbing device III which is illustrated in Figs. 1 and 2, the inner or fixed end of the resilient arm I2 is attached to the base II by being bonded or vulcanized thereto so that the arm and base together constitute a simple selfcontained bracket which can be economically manufactured and easily installed. It is not necessary, however, that the resilient arm I2 be connected with a base in the form of a plate as here shown, and for certain uses of the device, the plate I I could be an integral part of the arm.
The sleeve I3 provided in the outer end of the resilient arm I2 for use in mounting the load thereon, can be made of metal or suitable other material such .as a rubberized friction fabric. rhis sleeve extends through the arm and is bonded or vulcanized in place therein and is preferably of a length to project somewhat beyond the side faces of the arm.
r'Ihe load or object 2i) to be supported can be connected to the outer end of the arm I2 by any suitable connecting means and, `for this purpose, I have shown in.Fig..5 anattaching cliporbracket I5 connected with the load `and having spaced arms I5@ disposed against or adjacent the .ends of the sleeve I3. The clip I5 can be connected with the resilient arm I2 by means of a bolt .or pin I'I extending through .the spaced arms I5a and the opening of the sleeve .I 3. When the Aload 2i! is connected with the `resilientarm I2 ,in this manner it will be seen `that thepin I'I may act in the nature or pivot pin and will ihave small turning movementsin Ythe sleeve I3 Vduring the upward and downward movements of the load.
Instead of having vthe connecting pin I'I turn freely in the sleeve I3 of the resilientarm it may be desirable to retard or suppress such V,pivotal movements so as to obtain an additional vibration absorbing or dampeningfunction. This can be accomplished .by ythe construction illustrated in Fig. 6 in whicha friction lining I9 is provided between the wall of rthe Vsleeve I3 andthe connecting pin .I The lining I Scan be suitable friction fabric or can vbe a lining of soft rubber bonded or vulcanized to vthe inner vwall of the sleeve I3.
In Figs. 3 and 4 of thedrawings I have shownI a vibration mountingarrangement in which the load 23, such as a radio apparatus on a railway car, is supported by a plurality of the vibration absorbing 'devices I disposed vsubstantially in the plane of the center of .gravity ofthe load with their resilient-arms,extending longitudinally of lthe car. In this instance the support 2l, `onrality of pairs, of these vibration absorbing Vdevices. As shown in Figs. 3 .and -4 the vibration absorbing devices I-Il vhave their bases -II connected with the upright portions 22 and 23 ofthe support 2f! `by suitable boltsor fasteners .24 and have the outer yends of `their resilient -arms lI2 connected with the loadZIl by-the above described connecting clips I5 and pivot pins I'I.
When the load 2B has Abeen mounted `in this manneron a plurality 4ofthe vibration absorbing devices Il), it will be suspendedbetween the vvdevices as mentioned above andthe resilient arms I2 will be deecteddawnwardly .to .a ysubstantially horizontal loaded position and thereafter relative up and down movements/between the loadZD and the support 2| willcause corresponding flexings of the resilient arms in an upwardV and downward direction. Movements of the load 20 in a lateral direction transversely of the resilient arms I2 will cause corresponding lateral flexings of .these arms. Similarly, movements of the load in a longitudinal direction, that is, toward and from the upright portions 22 and 23 of the support will cause the resilient arms I2 to be flexed toward and away from these upright supporting portions. During these exings ofthe resilient arms I2 they act in the manner of cantilever members and the resilient arms will therefore effectively absorb vibrations and shocks which would otherwise vbe transmitted' between the load and the supports. Moreover, when the. arms I2 have been deected by the static load 20 to the substantially horizontal position mentioned above and endwise vibratory movements. or shocks occur in either direction, the force of such vibratory movements or shocks will be absorbed by causing the rubberlike material of the arm or arms located at one end of the static load to be subjected to compression. This is an advantage because rubber` and rubber-like materials are strong and durable when being used in compression for cushioning purposes. If desired, suitable resilient-bumpers 25 can be provided on the support 2I atoneor more points beneath the load 28 to take care of abnormal deflections.
Fig. 7 of the drawings shows a modied construction in whichstop means is provided for controlling the extent and rate of deection of the resilient arm I2. In this modified construction a substantially rigid stop member V26, made of metal plate or other suitable material, is provided for this purpose and is located so as to cooperate with the lower face 21 of the arm and another such stop member 28 is located so as to cooperate with the upper face 29 of the arm. Although the arm I2 can have any desired crosssectional shape as mentioned above, its lower and upper longitudinal faces 21 and 29 are preferably flat, as shown in the drawing, so as to provide for a relatively large area of contact with the stop members 26 and 28. The lower stop 26 has its inner end 26a fixed to or held against the base I I as by means of the mounting screws 30 and has an outwardly and downwardly extending longitudinally curved substantially flat portion 2Gb adapted to be engaged by the flat lower face 21 of the resilient arm I2. The upper stop 28 has its inner end 28a similarly connected to the base I I and has an outwardly and upwardly extending longitudinally curved substantially flat portion 28h adapted to be engaged by the fiat upper face 29 of the resilient arm. During downward flexing of the arm I2 the face 21 engages progressively increasing portions of the stop 26 and thus produces an increase in the rate of resistance to downward deflection of the arm. The curved portion 28h of the upper stop 28 serves in a similar manner to increase the effective resistance of the arm I2 to deflection in an upward direction.
The stops 26 and 28 just described above are preferably employed in pairs with such stops located below and above the arm I2 as shown in Fig. 7 although, if desired, either the upper or the lower stop could be omitted depending upon the flexing characteristics desired in the resilient arm. Likewise, it should be understood that although the stops 26 and 28 are here shown located below and above the resilient arm they can be located adjacent the side faces of the arm so as to control the rate of the lateral flexngs iinstead of, or in addition to, controlling the flexings in a vertical direction. Additionally, it should be Vunderstood that the flexible arms of the mounting illustrated in Figs. 3 and 7 can embody either the plain pivotal connection of Fig. 5 or the frictional pivotal connection of Fig. 6.
From the foregoing description and the accompanying drawing it will now be readily understood that this invention provides an improved vibration absorbing device which can be economically manufactured and installed and which embodies a resilient arm adapted to function asa cantilever member in supporting an applied load. It will also be seen that the improved device can be constructed in the form of a simple bracket and that the stresses produced in the resilient arm by the applied load will be so distributed that the flexibility of the rubber or rubber-like material will be utilized to maximum advantage. It will also be seen that the novel stop means herein disclosed provides for controlling the rate and extent of flexibiilty in the improved vibration absorbing device.
Although the vibration absorbing devices of the present invention have been disclosed herein in considerable detail, it will be understood, of course, that the invention is, nevertheless, intended to include all changes and modifications coming within the scope of the appended claims.
Having thus described my invention, I claim:
1. A vibration dampener in the form of a bracket comprising a substantially rigid base adapted to be connected with a support, a tapered resilient arm of rubber-like material connected With and projecting from the base and having a cross-section decreasing gradually in a direction outwardly from said base, the taper of said arm imparting thereto a resistance to deflection from shock loads applied to its outer end and which resistance increases substantially in proportion to the magnitude of such shock loads.
2. A vibration dampener in the form of a bracket comprising a substantially rigid base adapted to be connected with a support, a tapered resilient arm of rubber-like material connected with and projecting from the base and having a cross-section decreasing gradually in a direction outwardly from said base, said arm having an opening therein adjacent its outer end, a pin extending through said opening for attaching a load to said arm, and friction means in said opening and engaging said pin.
3. A vibration dampener comprising a resilient cantilever arm of rubber-like material having a base at its inner end adapted for fixed connection with a support and also having transverse pivot means extending through its outer end for the pivotal mounting thereon of a predetermined load to be supported, said arm being tapered and having a decreasing cross-section in a direction away from said base and toward said outer end such that under said predetermined load the arm assumes an arched condition in which it has relatively increased resistance to deflection from shocks applied to the arm substantially endwisethereof.
4. Al vibration dampener comprising a base adapted for connection with a support, and a resilient cantilever arm of rubber-like material connected to said base and extending in inclined relation thereto and provided with means spaced from said base for attachment of a predetermined load to be supported. said arm being tapered and having a decreasing cross-section in a direction away from said base such that Aunder lsaid :predetermined jload the :arm assumes :an :arched .condition 7extending .substantially :at right. angles to said base andin whichcondition it has .increased .resistance Y.to deiiection from shocks :applied lto the farm substantially .endwise thereof.
f5. .A ,vibration .dampener comprising .a substantially rigid base adapted .to vbe xedly connected with ia isupport, `a resilient .cantilever arm of `rubber-.like material having large land small .inner and .outer 'ends .andan :outwardly `decreasing longitudinal taper .and .having its inner end .connected to .said base :so that'the arm projects -outwardly therefrom .in an 'inclinedirel'atiom the itaper :and :inclination of said arm imparting Ythereto a .resistance Ato deiiection `from .shock :loads applied to its outer :end and `which resistance increases substantially in proportion `to the rma'gnitude :of such shock loads, and .pivot means `carried 'by said outer end for pivotally .connecting a load to be supported with `said outer end.'
6. A vibration dampener comprising'a substantially rigid base adapted to be connected with a support, a tapered Aresilient arm of rubber-'like material connected with and projecting from-said `base .and having a .cross-sectiondecreasing Agradually :in va :direction outwardly from said base, `the taper of said arm imparting .thereto a resistance .to deflection `from shock 'loads applied to .itsouter .end .and which resistance increases substantially .in `proportion to the .magnitude 'of 'such :shock lioads, :and .fa .stop .extending :along a Iportion of :said -arrn .and adapted itc be :engaged progressively Vtlierealong by :said-.farm upon .predetermined Vflexing .of vthe .latter in .a `direction toward :the stop.
.7.. A AVibration dampener .comprising a resilient arm :of r.ul;loer-like material having Vinner .fandiouter large andsmallends andan outwardly .decreasing vlongitudinal taper .between said .'ends, .connecting-means von v.said arm .iat 'the large Yend thereof for .xedly connecting 'said .large end with :a :support Afor mounting :said .arm .on said Isupport :in .outwardly projecting .relation .thereto, -.and `pivotmeans carried fby the :small outer .end 'for ipivo'tally connecting .a load vto be supported with :said xouter Send.
DAN T. BRADLEY.
Name `Date Erohlich et a1. Oct. 3, 1933 'Gwinn 50ct. .2-1, 1941 Kaemmerling Apri-7, y19.48 'Beam AJune 8, 1948 JFOREIGNMPTENTS .Country V:Date Great Britain. Sept. :28, .19.36