Патент USA US2405382код для вставки
fit; » §96 ' I > ` _ E.,voLET ACCELEROMETER original Filed Feb. 24„ 194; ' v ¿495,82 ' , Patented Aug. 6, 1946 2,495.382 UNITED STATES PATENT OFFICE` 2,405,382 ACCELEROMETER Edouard Volet, Vevey, Switzerland Griginal application February 24, 1943, Serial No. 476,985, now Patent No. 2,358,894, dated Sep tomber 26, 1944. Divided and this application June 28, 1943, Serial No. 492,620. In Switzer land February 5, 1942 2 Claims. `1> 2 This application is a division of my copending ing axis or spindle canbe very easily performed. A still further object of the invention is to pro vide an improved accelerometer as aforesaid in corporating a fluid operated relay having a piston driven by a revolving shaft and fitted with a pipe extension whose outlet port can effect on application Serial No. 476,985, ñled February 24, 1943, now Patent No. 2,358,894 issued September l 26, 1944. It is known that several types of accelerome ters are already in existence and use particularly for adjusting the operational speed of turbines. Generally speaking, known accelerometers com the one hand a relative angular motion With re spect to the operative wall of an aperture in an prise an inertia mass elastically secured to a shaft inertia mass rigid with-a twistable spindle fast so'driven by a belt or by a motor fed or energized 10 upon said shaft, said angular motion varying the by the machine which requires to be regulated as. to truly follow all speed variations of said rate of ñuid delivery through said port and on the other hand such a relative translatory mo tion as to restore the iiuid delivery to normal machine. Owing to this arrangement, each speed variation of the shaft brings about a relative value connoting balanced condition of the relay angular displacement between the inertia mass 15 and proper working of the machine. , elastically secured to its shaft and some suitable With these and such other objects in view as part rigidly driven by said shaft. As the value of will incidentally appear hereafter, the invention said angular displacement is in terms- of the comprises the novel construction and combina acceleration, it can be used as a measure there tion of parts that will now be described with ref of. Moreover, in known accelerometer construc 20 erence to the accompanying diagrammatic draw tions, the inertia mass is generally secured to its ing which illustrates suitable embodiments of the driving shaft by means of elastic arms. This ar same and which forms a part of the present dis rangement is not entirely satisfactory because a closure. . , very long and difficult job is involved in assem In the drawing: V bling said arms and properly setting and truing 25 Figure 1 is a vertical sectional view of an ac up their operative length and resiliency. celerometer built for operating a hydrostatic It is an object of the present invention to pro relay. , vide a new or improved accelerometer pertaining Figure 2 is a fragmentary sectional viewtaken to the aforesaid type but adapted to obviate the foregoing disadvantages owing to the fact that 30 the inertia mass is rigidly secured to one end of a twistable bar, spindle or axis whose other end is rigidly driven by the shaft the speed variations of which it is desired to measure, whereby meas uring of the acceleration of said shaft is read ily derived from the degree of elastic distortional along the line II-II of Fig. 1. y Figure 3 is an isometric view partly broken away for the sake of clearness of a more in volved constructicnal embodiment of the ac celerometer. ' . As will be seen from the showing of Fig. 1, there is provided a motor l so fed or energized from the machine which requires to bc regulated as to truly follow all the speed variations of twist of said bar or spindle. Another object of the invention is to provide this machine. One end of the motor shaft`2 or like actuator has fixed thereto a spindleV 3 con tremely simple and yet rugged structure calling 40 stituted by a twistable steel or like bar, thereby _For no delicate adjustment and made up of a permitting said spindle to undergo a high re minimum number of parts capable of being ma silient twist responsive to a relatively small tor chined beforehand and readily assembled to cor sional torque. The free end of the spindle 3 has rect operational positions. ~ rigidly ñxed thereto an inertia mass Il in the form Yet another object of the invention is to pro of a wheel or spider extending substantially> at vide an improved accelerometer as aforesaid in right angle to the spindle 3. an improved accelerometer as aforesaid of ex corporating simple means whereby its speed droop or statism, i. e., the relation between the speeds of the machine in idle running condition and in full load running condition, can be readily set tc proper value. A further object of the invention is to provide an improved accelerometer as aforesaid includ As will be readily understood, each speed vari ation of the driving shaft 2 produces, owing to the inertia mass which must be driven thereby, a torque the tendency of which is to twist the spindle or bar 3. Such torque exerts a torsional stress upon said spindle. The_value of said tor sional stress or twist is in terms of the accelera l ing simple means whereby centering and balanc ing of the inertia mass with respect to its carry 55 tion. As a result of this, the mass 4 is angularly displaced with respect to the actuating shaft _2. 2,405,382 4This displacement is a measure of the accelera tion. In the constructional form of the accelerome ter shown in the drawing, the angular displace ments of the inertia mass 4 hydrostatically oper ate a differential relay 5 by throttling or open 4 tudinal slots 23 extending parallel to the rota tional axis and with a slot 24 extending obliquely to said axis. Moreover, the sleeve unit thus formed has rigidly ñxed thereto a plate'4 I8 into which is fitted one end of a spindle I9.,? This spindle is aligned with the shaft 2 and has its other end provided with an intermediate member ing out more or less (as the case may be) an 26 fixed in turn to a yoke member 2l engaged outlet port E formed in a member connected to, through the slots 23 and rigidly connected to the and non-distortably driven by, the actuating inertia mass 4 which is cylindrical and freely en shaft 2 through the medium of a toothed wheel 'l 10 compasses the sleeve unit. The cam slot 24 forms which is fast upon said shaft and which in turn a guide for a block 25 rigid on the pipe 8 formed drives a bar I5 integral with a hollow rod or at its free end with the outlet port 6. The pipe pipe 8 of cranked outline whose upper end termi S is engaged through an elongated aperture 26 nates in the port 6. The latter is arranged in formed in the mass 4 parallel to the rotational front of a radially extending slanting wall 9 de axis. The port 6 is formed at the end of the fining an aperture in the mass il as shown in pipe B in front of the operative face 21 of the Fig. 2. aperture 26. The pipe 8 is connected at its end The relay comprises a cylinder in which is slid remote from the port 6 to a differential hydro ably and revolubly housed a piston l0 defining a static relay similar to the one described with pair of chambers l l, l2 of varying volumes inter 20 reference to Fig. l. connected by an accurately gagedl narrow chan The spindle i8 is capable of being twisted, nel i3 and receiving fluid from an inlet pipe i4. wherefor it has a small diameter and is made of The upper chamber l2 communicates through a material having a high mechanical strength to port 8a with the pipe 8 which, as above stated, gether with a high degree of resiliency so that terminates in the port 6. when the shaft 2 undergoes a change of speed, As will be observed, any angular displacement the inertia of the mass ¿l brings about a resilient of the inertia mass 4 moves the radially extend torsion of the spindle i9 and therefore a rela ing wall 9 olf or toward the port 6, thereby alter tive angular displacement of said mass 4 with re ing the intensity of fluid delivery therethrough. spect to the sleeve Il. This unmasks the port 5 30 Such alteration breaks the equilibrium' between and alters the rate of huid flow therethrough, those thrusts exerted on both faces of the piston thus varying the fluid pressure inside the pipe ß. which is therefore axially shifted. As a result Such angular displacement is a linear function of this, the port B effects’ a translatory motion of the acceleration. since the bar l5 has a slidingr ñt in a sleeve |62 As described with reference to Fig. l, a varia formed integral with the wheel l. As the radially " tion in the rate of fluid flow through the port 6 extending wall 9 slants with respect to the >rota breaks the balance between the thrusts exerted tional axis of the inertia mass 4, such a dis on both faces of the piston i9. Consequently the placement of the port 6 along the slanting wall - latter is shifted and moves with it the pipe 8. 9 tends to correct the alteration of iiuid flow In the construction shown in Fig. 3, the orien intensity caused by the angular displacement of 40 tation of the Obliquity of the guiding or camming the mass 4. Consequently the piston lil re slotI 2f! is so provided as to cause the longitudinal displacement of the piston lû to bring about a trieves a balanced position as soon as the inten restoration of the original rate of delivery through sity of fluid delivery through the port 6 has re the port 'ô by shifting the angular position of said sumed its original value. » As will be seen, it is the inclination of the ra 45 port with respect to the wall 2l. Consequently the Obliquity of the camming slot 24 determines dially extending wall 9 which provides for proper the speed droop of the accelerometer or in other speed droop of the accelerometer or in other words words the ratio between the speed of the machine for the relation between the speed of the ma when it runs idle and its speed when it runs un chine When it runs idle and its speed when it runs under full load. In order to modify the' value 50 der full load. It is evidently possible, with a view to allowing of a variation of said speed droop, of said speed droop, it would be suiiicient for ex to provide a guiding slot 24 ’having adjustable ample to provide for said wall to be orientatable under the control of a movable member ñxedly obliduity or camming action. It will be seen that the aforesaid accelerometer secured to the mass 4 by means of any known or conventional device enabling the degree of slant 55 has an extremely simple construction and calls for no precise adjustment inasmuch as all the of said wall V9 to be altered with respect to the parts of which it is made up can be built and ma rotational axis of the mass 4. Owing to such an chined beforehand and then assembled together arrangement, it would become possible to also >without requiring any special manipulation or modify the speed droop of the accelerometer by varying in any conventional way the useful length 60 skilled labor. As the inertia mass 4 is rigidly iixed to its carrying spindle, proper centering and of the spindle or in other words the distance balancing thereof present no diilìculty whatever. between the point at which it is fitted to the shaft Obviously the angular displacement of the mass 2 and the point at which the mass 4 is secured. 4 with respect to the driving shaft 2 may be meas Alternatively the speed droop of the accelerometer might be varied by imparting-by means of a 65 ured by means of a device other than the one de scribed in the foregoing. Such displacement may conventional device, an adjustable inclination to be measured for example optically by means of a the bar l5 with respect to the rotational axis of pair of disks formed with slots, one of said disks the mass 4 and also by arranging for the wall 9 being integral with the mass 4. while the other to extend in a plane passing through said rota disk is integral with or secured to the shaft 2. 70 tional axis. Alternatively such displacement may be meas The constructional embodiment of the accel ured electrically by varying the coupling condi erometer shown in Fig. 3 comprises a sleeve I1 tions between a pair of coils or windings, one of rigidly secured to the shaft 2 which revolves as which is supported by the mass 4 while the other shown by the arrow. The sleeve I1 has a cylin drical extension 22 formed withv a pair of longi 75 one is driven by the shaft 2. 5 2,405,382 Minor constructional details might be changed 6 2. An accelerometer for maintaining constant speed of an operating machine, comprising, in without sacrificing the aforesaid advantages or departing from the scope of the sub-joined claims. combination, a driven shaft, a rotatable member What is claimed is: ñxed to said shaft to rotate therewith, said mem l. An accelerometer for maintaining constant Ul ber having guide means extending parallel to the speed of an operating machine, comprising, in axis of rotation of the said member and also hav combination, a driven shaft, a sleeve ñxed to ing a cam surface extending obliquely to said said shaft to rotate therewith, said sleeve having axis, an annular inertia mass arranged co-axially a pair of longitudinal slots extending parallel to with the shaft and having an aperture; a twist the axis of rotation of the sleeve and also hav 10 able resilient spindle arranged co-axially with ing a cam slot extending obliquely to said axis, the shaft, rotatable member, and annular iner an annular inertia mass arranged co-axially with the shaft and having an aperture; a twistable re silient spindle arranged co-axially with the shaft, sleeve, and annular inertia mass; means for con necting one end of the spindle rigidly to the sleeve, a yoke member rigidly connected to the other end of the spindle and having its outer end portions engaged in said longitudinal slots of the sleeve, tia mass; means for connecting one end of the spindle rigidly to the rotatable member, a yoke member rigidly connected to the other end of 15 the spindle and having its outer end portions engaged with said guide means and cam surface, and means to transform the angular movement of the inertia mass into an axial movement for modifying the speed of rotation of said shaft and twist responsive means for modifying the 20 through the relative differential movement be speed of rotation of said shaft through the rel tween the inertia member and the rotatable mem ative differential movement between the inertia ber, said means including a fluid cylinder dis member and the sleeve, said means including a posed co-axially with the shaft and spindle, iluid cylinder disposed co-axially with the shaft a ported piston in said cylinder dividing the and spindle, a ported piston in said cylinder divid 25 same into opposite chambers, a cranked hollow ing the same into opposite chambers, a cranked pipe element connected at one end with the pis hollow pipe element connected at one end with ton and communicating with one of the chambers the piston and communicating with one of the of the ñuid cylinder and, having its other end chambers of the ñuid cylinder and having its terminating in a port disposed in said aperture other end terminating in a port disposed in said 30 of the inertia member, and means carried by the aperture of the inertia member, and means car pipe element and slidable on the cam surface of ried by the pipe element and slidable in the cam the rotatable member whereby relative movement slot of the sleeve whereby relative movement be between the rotatable member and inertia mass tween the sleeve and inertia mass will move the will move the port of the pipe element into and port of the pipe element into and out of engage 35 out of engagement with a wall'of the said aperture ment with a wall of the said aperture in the in the annular member. annular member. EDOUARD VOLET.