US1912924A - Speed responsive apparatus - Google Patents

Description

SPEED RESPONS IVE APPARATUS Filed Nov. 24. 1951 s Sheefs-Sheet 1 Brake Controlling Mayne! Canmnt L Time my. 2. (fitment 1 INVENTORS Tum-9 P9P Utne and 9 Ralph 1000 9.

Q/RW

THEM/1110mm.

Patented June 6, 1933 UNITED STATES PATENT oFFIcE PER UTNE AND RALPH K. CROOKS, OF EDGEWOOD, PENNSYLVANIA, ASSIGNORS TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A COR- PORATION OF PENNSYLVANIA SPEED RESPONSIVE APPARATUS Application filed November 24, 1931.

Our invention relates to speed responsive apparatus, and particularly to improvements in speed responsive apparatus of the type described and claimed in an application for Letters Patent of the United States, Serial N 0. 551,967, filed by Frank H. Nicholson, on July 20, 1931.

Speed responsive apparatus embodying our invention is particularly suitable for, although in. no way limited to, use for controlling circuits in conjunction with speed control systems for railroads.

We will describe three forms of apparatus embodying our invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a view, partly in section, partly in side elevation, and partly diagran'imatic, illustrating one form of apparatus embodying our invention. Figs. 2, 3, 4 and 5 are diagrams, showing graphically, the operating characteristics of a portion of the apparatus illustrated.

in Fig. 1. Fig. 6 is a view, similar to Fig. 1, showing a modified form of the apparatus illustrated in Fig. 1, and also embodying our invention. Fig. 7 is a diagram, showing graphically, the operating characteristics of a portion of the apparatus illustrated in Fig. 6. Fig. 8 is a View, partly in side elevation, partly in section, and partly diagrammatic, illustrating another form of apparatus embodying our invention. Fig. 9 1s a sectional view-taken on the line IXIX of Fig. 8. Fig. 10 is a view showing a modified form of a portion of the apparatus illustrated in Figs. 8, and 9, and also embodying our invention, and Fig. 11 is a sectional view taken on the line XIXI of Fig. 10.

Similar reference characters refer to similar parts in each of the several views.

Referring first to Fig. 1, speed responsive apparatus embodying our invention embraces suitable speed responsive circuit interrupting means, designated as a whole by the reference character M, and here shown as comprising a rocker 1 and an inertia member 2 which cooperates with the rocker 1. The rocker 1 is mounted to oscillate about a suitable shaft indicated at 3 in the drawings, and is intended to be operatively connected with Serial No. 577,057.

any body or device whose linear or angular speed it is desired to measure, in such manner that the frequency of oscillation of the rocker will be proportional at all times to the speed of the body or device, In the embodiment illustrated, the rocker 1 is operatively connected with the axle 6 and wheel 7 of a car. or locomotive, not shown in the drawing, by means of a connecting rod 4. The connecting rod 4 is pivoted at one end on a pin 1 carried by an extension 1 on the rocker 1, and atthe other end on a crank pin 5 which is eccentric to the axle 6 and wheel '7. It will be apparent, therefore, that when the wheel 7 is rotated,the rocker 1 will be oscillated at a frequency which is directly proportional to the speed of the Wheel, the

frequency of the rocker being increased as the.

speed of the wheel increases, and decreased as the speed of the wheeldecreases. It follows, therefore, that the frequency of oscillation ofthe rocker will increase ordecrease as the linear speed of the locomotive or car of which the wheel 7 forms a part increases or decreases. It should be distinctly understood, however, that the particular arrangement shown is utilized merely for the convenience in describing our invention, and not by way of limitation.

, he inertia member 1 is pivotally mounted on a shaft 9 carried by the rocker 1 and, in the form'here shown, comprises two spaced weights 2 and 2 conn-ectedby integral webs 2 and 2 with a sleeve portion 2 which re-' ceives the shaft 9. Interposed between an arm 11 secured to the weight 2- and an adjustable spring support 12 screwed through the web 1 of the rocker 1, is a coil spring 13 which biases the inertia member 9 to a position in'which a contact member 14 secured to the weight 2 engages a contact member 15 attached to, but insulated from, theweb 1 of the rocker 1. The spring support 12 is locked in an adjusted position by means of a lock nut 16.

The apparatus also includes a reactance X and an electroresponsive indicating device, here shown as a relay R. The reactance X and relay R are connected in series in a circuit which passes from terminal B, of a suitable source of current not shown in the drawing, through rocker 2, contact 1% 15, reactance X, and the winding of relay R to the other terminal O of the source. Connected in multiple with reactance X and relay R in the circuit just raced is an asymmetric unit A which is so disposed that it will offer its highcst res stai ce t) current which tends to flow through the branch path including this unit from terminal. B to terminal of the source. Relay R is nferably made slowacting for re: sons which will a ipear as the description proceeds.

"rho operation, as a whole, of the apparatus thus tar des bed is as follows: As previousiy poinced out, vhen the wneel 7 is rotated, the rocker 1 is oscillatec ata frequency which incrc; cs as the speed of rotation of the wheel T increases. At all frequencies of oscillation of the rocker, the motion ot the rocker is substantially simple harmonic motion, and itwill be apparent, lherci'or that when the rocker is oscillatin it causes an accelerating to co to be exerted which varies according to a sine curve. 'inzs accelerating force is alwavs in opposition to the tcrce causing the displa ement of the rocker from the position in which it is shown in Fi and it will be readily understood that during that portion of each oscillation in which the lOCliLl is being rotated in a clockwise direction from the position shown in Fig". 1, this accelerating force is transmitted to the rocker through the spring 13. That is to say, during that portion 0t each oscillation in which the rocker 1 is being rotated from the position shown in Fig. l in a clockwise direction, the accelerating force of the inertia member is opposed by ,the force of the spring 13. The magnitude of the accelerating force acting on the inertia member increases with increases in the fre quency of oscillation of the rocker according to the square of the trequency, and it will be seen, therefore, that as long as the frequency of oscillation of the rocker remains below some frequency which we shall term the critical tr-eruicucy. and which depends upon the proportioning of the parts, the accelerating force acting on the inertia member will always be less than the opposing force of spring and under these conditions, contact ii-l5 will remain continuously closed. is soon, however, as the frequency of oscillation of the rocker increases beyond this critical. frequency, a condition will be reached during some portion of each osrilla'ltion in waichthe accelerating force acting on the inertia member is greater than the opposing force on the spring, and when this happens, the spring will no longer be able to hold the inertia member against the rocker, with the result that the spring will become compressed and permit contact to open. hen the contact has once opened, the motion of the inertia member is governed by the inertia of the inertia member and by the opposing force of the spring. The opposing force of the spring depends, among other things, upon the relative posit on ot the inertia member with respect to the rocker, and it will be clear, therefore, that alter the contact has once opened, the inertia i'neinber will continue to move in the direction to increase the contact opening for a time, but will soon come to rest, and will then move with incre sing velocity in a direction to again close the contact. Considering the motion of the rocker during this time, it is evident that its acceleration in- ?rea es to a negative maximum as it comes to rest at the end of its stroke in the clockwise direction of rotation, and then decreases as it moves in the opposite direction, becoming zero at mid stroke. At some point after the rocker has reversed the direction of its rotation from clockwise to counter-clockwise. the acceleration oi the rocker vill be less than that which caused the contact to open. \Vhen this happens, the rocker and inertia member will each be moving in the colintor-clockwise direction. and the inertia member will be zmcclerating at a rapidly increasing rate. It is evident, therefore, that the contact will again become closed during each oscillation at some later point in the cycle than the point at which it opened. Since the acceleration of the inertia member varies as the square of the frequency of oscillation of the rocker. it follows that the length of the open time of contact l-ll;l5 during each oscillation will rapidly increase, and the length of the closed time will rapidly decrease, with slight increases in the frequency of oscillation of the rocker beyond the critical frequency. It should be pointed out, that, since for a given proporlioning of the parts, the weightof the inertia member and the relative locations oi the shafts l) and 23 are fixed, the critical frequency at which contact il -15 lirstopens, may be varied by varying the adjustment of the spring 13.

As was previously pointed out, contact ll lo is included in the circuit for reactance X and relay R, and it follows that when contact l-'l-15 is closed, this circuit will be closed, and current will therefore be supplied to the winding of relay R. It will be readilv understood, however, that due to the inductance of this circuit the current in the wind-- ing of the relay will not build up to its Ohms law value immediately upon the closing of this contact, but will follow a time constant curve similar to the curve 18 shown in Fig 3. Likewise when contact 1+ll5 is opened, the circuit for reactance X and relay R will become interrupted, and the supply of current to the relay will therefore be cut oil. At the instant the supply of current to the relay is cut oil, the current in the winding of the relay will start to decrease, but due to the of contact ll15 increases, and the closed time decreases, as the frequency of oscilla' to a lower value. The periodically varying energy stored in this winding and in reactance X, a circulating current will be set up in the closed circuit including the winding of the relay, reactance X, and asymmetric unit A, and this circulating current will delay the decay of current in the winding of the relay in a manner which is indicated graphically by the time constant curve 17 shown in Fig. 2. It will be seen, therefore, that if contact 1 e 15 is alternately opened and closed at a fixed rate, as is normally the case when the rocker is being oscillated at any constant frequency above the critical frequency, the current in the winding of the relay will first decrease during each oscillation along some portion of the curve 17 to some value which depends upon the initial alue of the current in the winding of the relay at the instant contact l t-15 became opened, and upon the length of time the contact remains opened, and will then increase along some portion of the curve 18 to the same value which it had when the contact last became opened. This grmvth and decay of the current in the winding of relay R at one particular frequent-y of oscillation of the rocker above the critical frequency indicated graphically by the curve 20 shown in Fig. l. Referring to this ligure, the line ?)-0 of the curve 20 represents the decrease in current in the relay Winding during one oscillation, and the line c-Z) indicates the increase in current during the same oscillation. During the next succeeding oscillation, the decrease in current is represented by the line b c and the increase in current by the line 0 -45 etc. It will be seen, therefore, that at one particular frequency of oscillation of the rocker above the critical frequency, the winding of the relay will be supplied with a periodically varying current, the average value of which is indicated by the line 21 in Fig. 4.

As described hereinbefore, the open time tion of the rocker increases beyond the critical freq uency. It will be readily understood, therefore, that at the higher frequencies of oscillation of the rocker, the current has less time to build up, and consequently does not build up to such a high value as it d oes at the lower frequencies. Also, since the open time of the contact is greater, the current decays current which is supplied to the relay winding when the rocker is oscillating at a frequency which is somewhat higher than the frequency of oscillation corresponding to that for the curve 20, is indicated by the curve 22 shown in Fig. 4, and the average value of the current which is supplied to the relay winding under these conditions is indicatcd by the curve 23. From a comparison 0f the curves 20 and 22, it will be seen that as the frequency of oscillation of the rocker increases beyond the critical frequency, the average current in the relay winding decreases.

Referring now to Fig. 5, the curve 24: here shown a typical curve indicating the man her in which the average value of the current which is supplied to the relay winding varies with variations in the frequency of oscillation of the rocker 1 for one particular proportioning of the parts. From an inspection of this curve it will be seen that, at all frequencies below the critical frequency, the average value of the current in the relay winding is substantially constant. The reason for this is that, since contact l415 remains closed at all frequencies below the critical frequency, the current in the winding of the relay builds up to, and remains at, its Ohms law value. As soon as the frequency of oscillation of the rocker passes the critical frequency, however, so that contact 1 l15 starts to periodically open and close, the average value of the current in the relay winding starts to decrease, and as the frequency of oscillation of the rocker continues to increase, the current decreases more and awe rapidly until, at a narrow band of frequencies ust a little above the critical frequency, the decrease is very rapid. As the frequency further increases beyond this narrow band of frequencies, the decrease in current becomes less marked until a frequency is finally reached at which the rate at which the contact 14-15 interrupts the circuit for the reactance X and relay R becomes so high that substantially no further decrease in current takes place.

As was pointed out hereinbefore, relay R is a slow-acting relay, and it will be readily understood, therefore, that by properly proportioning its parts, this relay may be made to respond to the average value of the current supplied to its winding, and not to the instantaneous value. It will be seen, therefore, that by constructing this relay to have picleup and release values which fall on some portion of the curve 24, the relay will be picked up at all fIOQHOUCiQS of oscillation of the rocker bclow the frequency corresponding to the picle up value, and will be released at all frequencies of oscillation of the rocker above the fre quency corresponding to the release value.

For example, if the relay. is provided with the lay will remain 1L at whicl v.re relay picks up is passed. Itw1ll he rcincniocrcd that the critical frequency of the roclter depends upon the proportioning of the parts, and that for a given proportioning of the pa: is. this frequency may be varied by adjusting the position of the spring support 12 to vary the biasing force exerted by the spring 12'}. ll ill be seen, therefore, that by p 'operly selecting the electrical and mechanical elements of the apparatus, and by properadjustin' the biasing force of the spring relay may be made to pick up and release its armature at any desired frequency of oscillation of the rocker. and hence, at any desired linear speed of the car or locomotive with which rocker is o ieratively connect cd. It will also be seen that by adjusting the pick-up and release values of the relay R to such values that they fall on the steep portion of the curve as indicated by the lines 25 and :26, the relay may be made to pick up and release its armature at frequencies which (lifter in magnitude by only a small amount. "lhis particularly desirable when the relay is to be utilized for controlling circuits in connection with speed control systems for railroads.

When relay R is picked up, its front contact 1919- is of course closed, and when the relay is 'eleascd, its back contact 1919" is closed. The contacts of the relay may be utilized to control the circuits for any suitable clcctro-responsivc device or devices in such manner that the device or devices will occupy one condition when the relay is energized and another condition when the relay is deenergized. For example, when the apparatus is operativcly connected with some part oi. the running gear of a car or locomotive, as is the case in the embodiment illustrated, so that the frequency of oscillation of the rocker 1 varies with the linear speed of the car or locomotive, relay ll may be utilized to control a speed governing device for the car or locomotive. As here shown, relay R controls a brake controlling magnet E which applies the bralzcs on the car or locomotive when this magnet bet-or deencrgized. The circuit for magnet E is carried over front contact ilk-l9 of re ay R. t will be apparent, therefore. from the foregoing, that as long as the speed of the car or locomotive is below some predetermined speed, magnet E will be energized. but that if the speed of the car or locomotive increases beyond this speed, magnet E will become deencrgized, thus enforcing a low speed limit on the car or locomotive. It should be definitely understood, however, that apparatus embodying our invention is in no way limited to this particular use.

Referring now to Fig. (3, the apniratus here shown is similar to that shown in Fig. l with the exception that the inertia member of the circuit interrupting means, which circuit interrupting means is here designated generally by the reference character M instead of being biased by means of the spring 13 to the position in which the contz ct l4- is closed as shown in Fig. 1, is biased by means of a spring 58 to the position in which the contact li-15 open. The spring 58 is secured at one end to the arm 11, and at the other end to an adjustable eyebolt 5t) which is screwed through the web .l" of the rocker 1. The eyebolt 59 is loclicd in place by means of a nut (30. An adjustable stop (ll limits the amount of opening of the contact i l-15.

With the apparatus constructed as shown in Fig. when the rocker l is oscillated. the inertia of the inertia member will aid the spring 58 in holding contact ll-i5 open (llll'llh-j a portion of each oscillation but will tend to s-ttretch the spring. and hence to close the contact l-l--l5, (ltll'lllgl' another portion of each oscillation as will be read ly undo"- stood from the foregoing description of Fig. 1. It will be apparent. therefore, that as long as the frequency of oscillation of the rocker remains below some critical frequency which depends; upon the proportioning of the parts and the :nliu:-:t1nent of the spring 58, contact l ll5 will constantly remain open, but that. as soon as the frequency of oscillation of the rocker becomes greater than this critical frequency, contact lslil5 will start to alternately open and close, the length of the closed time increasiinr, and the length of the open time decreasing. as the frequency of oscillation of the rocker increases beyond the critical frequency. As previously pointed out in connection with Fig. 1. when contact i l- 15 is open, the circuitfor reactance X and relay It is inter ruptcd, and the current in the winding of the relay decays. lVhcn this contact is closed, however. the circuit for reactance X and relay R is then closed, and the current in the relay winding builds up. .lt follows. therefore, that as long as the frequency of oscillation of the rocker is below the critical frequency, relay R will constantly remain decnergized. As soon. however, as the fre quency of oscillation of the rocker becomes greater than the critical frequency so that contact 1a15 becomes al ernatcly opened and closed. the winding of the relay will be supplied with a periodically varying current, the average value of which will increase as the frequency of oscillation of the rocker increase. The manner in which this increase takes place for one proportioning of the parts is indicated by the curve 62, shown in Fig. 7. Referring to this figure, it will be observed that as soon as the critical frequency of the rocker ispassed, the average value of the current supplied to the relay winding first increases gradually and then more and more rapidly until a narrow band of frequencies is reached between which the increase is very rapid. As the frequency increases beyond this narrow band of frequencies, the increase in current becomes less rapid until a frequency is finally reached where very little further increase in current takes place, and the average value of the current for further increases in the frequency of oscillation of the rocker then remains substantially constant. Since relay R is constructed to respond to the average value of the current supplied to its winding, it fol lows that by providing the relay with pickup and release values which fall on the curve 62, the relay will be released at all frequencies of oscillations of the rocker below the frequency corresponding to its release value, and will be picked up at all frequencies above that corresponding to its piclcup value.

When the parts are arranged as shown in Fig. 6, relay B may be utilized to control any suitable device in any desired manner. Referring now to Figs. 8 and 9, in the moditied form of our invention here shown, the circuit in terrupting: means is designated as a whole by the reference character M and is enclosed in a suitable casing C, which may, for example, be secured to some stationary part 31v of the car or locomotive in such manner that iis position with respect to the axle 6 of the car will remain fixed. ()ne side wall 33 of the casing; C is formed with a bearing 30, and the opposite side wall 34 thereof is provided with an opening 35. The opening 35 is closed by a suitable cover plate 36 having a bearing 29 formed therein which is in axial alignment with the bearing' 30. A horizontally extending shaft 38, to which a rocker 1 rigidly secured, is iournalled in the bearings 29 and 30. and the right-hand end 38 thereof extends through the casing and is provided with a era 1; 37. The free end of the (I'Ellsll' 37 is pivotally (7011110. l with the upper end of the connecting rod lpreviously described in connection with Fig. 1. It will be seen, therefore, that when wheel 7 is rotated, the rocker 1 will be oscillated at a frequency which increases as the speed of the wheel. and hence as the linear speed of the car, increases. For reasons which will appear hereinafter, the rightdiand end 38 of the rocker 1 is made tubular, and extendingfrom the interior of the casing through this tubular portion into the opening therein are a plurality of holes 39,.as clearly shown in Fig. 8.

Pivotally mounted on the shaft 38 between bosses 38 and 40 formed on the rocker 1 are a plurality of inertia'inembers 2, 2, and 2 Each of these inertia members is similar to the inertia member 2 shown in Fig. 1, and each is biased. by means of an associated adjustably spring 13 125 or to the position in which a contact finger 14, 14?, or 14 carried thereby engages a fixed contact member 15, 15 or 15 carried by the rocker, as will readily be understood from an inspection of Figs. 8 and 9. External electrical connections to all of the contact fingers 14 is made by means of a flexible conductor 41 which ex tends through the opez' ing in the tubular portion 38* of the r her 1 and through one of the holes 39, and which is fastened'to each inertia member by means of a suitable screw 45. External. electrical connections to the fixed contact members 15. 15 and 15 are similarly made by means of flexible conductorsll, 43 and l4, respectively, each of which extends through a different hole 39 into the opening 38 in the tubular end of the rocker 1 and is soldered or otherwise fastened at its inner end to the associated fixed contact me1n'' her. i

The contact 14E 15 controls the supply of current to an electrical circuit which passes from terminal 13 of the source through flexible conductor 41, inertia member 2 contact 1.4 15 flexible conductor 42, and an asymmetric unit A connected in multiple with a reactance X and the winding of a relay B9 in series, to terminal 0 of the source. The rcactance X, relay 11 and asyminetricu'nit 'A are similar in all respects to the reactance X, relay B and asyimnetric unit A. previously described in connection with Fig. 1. The contacts Li -15 and le -15 control the supply of current to similar circuits which will be a 'aparcnt from the drawings without describing them in detail.

The o 'ieration of the apparatus shown in Figs. 8 and 9, in so far as the elements associated with each inertia member is concerned,

is substantially the same as that previously described'in connection with Fig. 1, and will be readily understood without further description. It should be pointed out, however, that by properly adjusting the springs 13 associated with the different inertia menibers, the contacts 14 -15, la --15 and 1 l 15 may be made to first open at different frequencies of oscillationof the rocker 1, and under these conditions, the relays R", R and ll will operate at different speeds of the car or locomotive. thus enabling a plurality of different speed limits to be enforced on the car or locomotive.

Referring now to Figs. 10 and 11, we have here shown a modified form of the circuit interrupting apparatus illustrated in Figs. 8 and 9. As here shown, the rocker 1" cooperates with tl ee inertia members 2, 2

and 2, each of which is in the form of a. substantially rectangular block. Each of the inertia members is pivotally mounted on the shaft 38. and has secured to its face which is nearest the web of the rocker i a leaf spring 46, $6 or 46. The upper ends 01" the leaf springs l6, 16 and 46* are provided with Contact tips 4T. 47* and 47*. respectively, which cooperate with similar contact tips l8, only the. tip l8 which cooperates with the contact tip 47* being visible in the drawings. The contact tips 48 are each fastened to the upper ends of a fixed contact member 49, and the contact members 49, in turn, are fastened to, but insulated from the rocker l. The lower ends of the leaf springs 46*, T6 and 46 cooperate with suitable adjusting members 50, 50 and 50 in such manner that the inertia members are constantly biased by the springs to the positions in which the contacts etT 48, 47 '48 and *l7 4.-8 are closed. It will be apparent, therefore, that the leaf springs to serve both as contact fingers and as biasing means. The adjusting members 50, 5O and 5d are screwed through threaded holes in the web of the rocker l, and in the form here shown. each adjusting member comprises av metal plug 50 provided at its inner end with an insulating insert 56 which insulates the adjacent leaf spring from the rocker. Each adjusting member is maintained in its adjusted position by means of a lock washer 52 having a threaded hole 53 which receives the nieinber (see Fig. 11) and an integral lug tl'irough which a screw 54 which is screwed into the lOt'liQi 1 passes. To lock an adjusting member in an adjusted positioni the associated washer 512 is screwed onto the adjusting member to a position in which it is spaced a slight distance from the rocker. and the screw 5st is then tightened, thus binding the threads of the adjusting member. and hence preventing it from turning. It will be noted from an inspection of Fig. 10 that the lower portion of the inertia member 2 adjacent the spring lt) is curved as indicated at 57 in the drawings. This curvature is so shaped and arranged that the free end of the spring 46 becomes shorter and rapidly increases in stiffness as soon as the contact l i-15 has opened. This feature is important particularly when a comparatively heavy inertia member must be adjusted to open the contacts at a comparat-ive ly low speed and at the same time be capable of properly following the oscillations of the rocker at higher rates of speed without an excess opening of the contacts. The curvature of the lower portion of the inertia member also tends to decrease wear between the parts. The other inertia members are likewise cnrved in a similar manner. In the structure shown, it is intended that the contacts -LtT 48, 47 -etS and 47 48 shall first open at difierent frequencies of oscillation ot the rockers, and in order to facilitate this operation, the mass oi the inertia member which operates the contact which is intended to First open at the highest 't'rc picncics of oscillation of the marker is made somewhat less than the mass of the inertia member which operates the contact which is intended to open at the next lower freipicncy of oscillation of the rocker. etc. as wi l be clearly a i parent from an inspection of Fig. 10.

lVith the circuit interrupting means constrncted as shown in Fig. it) when the rocker 1 is operated, 'l-fjll inertia member cooperates wiih the rocker to control z'b associated contact in substantiz li the same manner as the rocker 2 shown in Fig. 1 cooperates with the rocker 1 to control the contact 1=l-15. The parts are so proportioned, however, and the springs 50 are so adjusted that the coin tact -l7 -4r.8 will first become periodically opened and closed at a relatively low frequency of oscillation of the rocker, the contact ai -4 :3 at a somewhat higher frequency of oscillation of the rocker. and the contact std-l8 at a still higher frequency.

The circuit interrupting means shown in Figs. 10 and ii is intended to be utilized in the same. manner as the circuit interrupting means M shown in Figs. 8 and Y). and when utilized in this manner. the operation of the apparatus as a whole. will be readily understood from the foregoing without describing it in detail.

Although we have hcrein shown and described only Your form of :1p ""'itus' eml'uuiying our invention. it is unde tood that wax-ionschanges and modifi ations may be maoc therein within the scope ot the appended claims without departing from the spirit and scope of our invention.

Having thus describcijl our invention, what we claim is:

1. Apparatus for indicating the speed of a movable body comprising a first men'iber adapted to be oscillated at a frequency which varies with the speed of the body, an inertia member pivotally mounted on said first member, a fixed contact member carried by said first member. a. second contact member carried by said inertia member. a spring carried by said first member and arranged'to bias said inertia member to a position in which said second contact member engages said lined contact member, and an electrorcsponsive indicatii'ig device controlled by the contact torn'ied by said second contact member and said lixcd contact member.

2. Apparatus for indicating the speed of a movable body comprising a first member adapted to be oscillated at a trcquency which varies with the speed of the body. an inertia member pivotally mounted on said first member. a fixed contact member carried by said first member, a second contact member carried by said inertia member and adapted to cooperate with said fixed contact member, a spring secured to said first member and to said inertia memb and arranged to bias said inertia member to the position in which the contact formed by said fixed contact member and said second contact member is open, and an electrcresponsive indicating device controlled by the contact formed by said fixed contact member and said second contact member.

3. Apparatus for indicating the speed of a movable body comprising a first member adapted to be oscillated at a frequency which varies with the speed of the body, an inertia member mounted to oscillate about the same axis as said first member, a fixed contact member carried by said first member, a second contact member carried by said inertia member, a spring carried by said first member and arranged to bias said inertia member to a position in which said second contact member engages said fixed contact member, and an electroresponsive indicating device controlled by the contact formed by said second contact member and said fixed contact member.

4. Apparatus for indicating the speed of a movable body comprising a first member adapted to be oscillated at a frequency which varies with the speed of the body, a pivoted inertia member, a fixed contact member carried by said first member, a second contact iii-ember carried by said inertia member, a spring carried by said first member and arranged to bias said inertia member to a position in which said second contact member ongages said fixed contact member, and an electrical circuit controlled by the contact formed by said second contact member and said fixed contact member, said circuit including an asymmetric unit connected in multiple with a slow-a itii'ig relay anda rucactance in series.

5. Apparatus tor indicating the speed oi a movable body comprising a first member which is adapted to be oscillatedat a fr quency which varies with the speed. of the body, a p urr inertia members pivotal- ..ity oi 1v mounted on said first member, a plurality oifixed contact members carried bv said first member, plz'raiity or other contact members one attached to each inertia member and each adai'ited to cooperate with a different one of said fixed contact members, a. plurality oi springs carried by said first member and each arranged to bias :1 different one of said inertia members to the position in which the contact incmliier -rarried by the associated inerti engages the associ; ted fixed being adjusted to exert ditl'crcnt biasing forces, and a plurality of clcctrm-osponsivc indim 'ing devices one controlled by the contact formed by each said other contact member and. the associated fixed contact member.

6. Apparatus for indicating the speed of a movable body comprising a first member which is adapted to be oscillated at a frequency which varies with the speed of the body, a pin 'ality of inertia members mounted to oscillate about the same axis as said first member, a plurality of fixed contact meniibers carried by said first member, a plurality of other contact members one attached to each inertia member and each adapted to cooperate with a different one of said fixed cont-act members, a plurality of springs carried by said. first member and each arranged to bias a different one of said inertia members to the position in which the contact member carried by the associated inertia member engages the associated fixed contact, said springs being adjusted to exert different biasing forces, and a plurality of electroresponsive in d' rating devices one controlled by the contact formed by each said other contact member and the associated fixed contact member.

7. In speed responsive apparatus for electrically indicating the speed of a movable body by periodically interrupting the supply of current to an inductive electrical circuit including an electroresponsive indicating device which is selectively responsive to the average value of the current in its winding,

in combination. circuit interrupting means comprising a first member os-illated at a speed which va ies with the speed or" the body, an inertiamember pivotally mounted on said first member, a fixed contact men'iber secured to said l.l1Sl31110111l)61', a second contact member carried by said inertia member, and a spring carried by said first member and arranged to bias said inertia member to a position in which said second contact member engages said fixed contact member.

8. In speed responsive apparatus for electrically indicating the speed oi: a movable body by periodically interrupting the supply of current to an inductive electrical circuit including an electroresponsive indicating device which is selectively responsive to the average value of the current in its winding, in con'ibination, circuit interrupting means comprising a first member oscillated at a speed which varies with the speed of the body, an inertia member pivotally mounted to oscillate about the same axis as said first member, a fixed contact member secured to said first member, a second contact member carried by said inertia member, and a spring carried by said first member and. arranged to bias said inertia member to a position in which said second contact member engages said fixed contact member. I

9. In speed responsive apparatus for elec trically lndicati. the spe d of a HIOVtIblQ p whi h a rerage value c l the current in. its wind inn, in combination, ri rcuit iuterr nling means comprising); a first member oscillated at a speed 'arics with the speed of the body, a plurality of inertia members pi votally mounted to ()FKlllZitC about the same axis as said lirwt member, a plurality of fixed contact members carried by said first member, a plurality of other contact members one carried by each inertia member and each adapted to cooperate with a different one of said fixed contact memb rs, and a plurality of springs by said first member and each (1'- to bias a difierent one of said inertia nein ers to the position in which the contact mcnibe' carried by such inertia member engage the associated iiried contact member, said springs being adjusted to exert difl'erent biasing forces.

10. In speed responsive apparatus for elecdly iniilicating the speed of a movable Jody by i ieriodically interriipting the supply oi irrent to an 3 Inductive electrical cir- -;r an eiectroresponaive indicatis s lcctivcl -r responsive to 10 current in its Windcombii ation. circuit interrupting a first member oscillated ii-"n c i] h avcra ye value oi tat a spcco \rnirh varies w th the speed of the an inert a member pirotally mounted to osriilat' about the same axis as said first contact member carried by he a leat spring; secured ti V iber and provided at one end -"liii a contact tip which cooperates with said lixcd contact memb r. and 11;}276 carl'ic 'l b) said, first contact member and eoope'ating with the other end oi said leai' spril'ig in such manner said spring biases said numbcr to the pwiiion in which sa d contact tip encontact member. Kfli resnonsivc ai'iparatus tor electhe speed oi, a movable ly interrupting the sup- 2 inductive electrical cirlectroresponsive indicats selectively responsive to of the current in its windiom circuit interrin'iting a first member oscillated with the speed of t 1e iemoer pivotally mounted to oscillate be same axis said first membe d con act member mirried by said lir.-;t member. a leat spring secured to said irerlia nicnihc and pr( vided at one end wit a contact tip which cooperates with said iixr-d cont ct member. and a pluit adjustably i'l' U'i i said first mem er and pro- .ts inner end with an insnlr-iting insert w ich cooperates with the other end of spring in such manner that, said y es said member to the pos tion in ivhich said contact tip engages said fixed contact member.

mendcr. a

l w. Dill ll. in s "h ram an irerti in 12. 1\1) 7Uf21tUH for imlicating the speed of a mo able body comprising a lirst member adapted to be oscillatei'l at a 'frcqueiuiy which varies with the speed oi the body, 7 pivoted inertia. n'em cr. a fixed contact member rarl'icd by said first member. a second Contact member carriml by said inertia member. a spring carried by said first member and arranged to bias said inertia member to a position in which said second contact member engages said fixed contact member, means for adju ting the biasing; force exerted by said spring, and an eleetrorcsponsive indicatin; device controlled by the contact formed by said second contact member and said fixed contact member.

13. Am aratus for indicating; the speed ot a movable body eomprising; a first member adapted to be oscillated at a Frequency which varies with the speed of the body. a pivoted inertia member. a iixed contact member carried by said first member. a second contact member carried by said inertia IIIODd'XH. a spring carried by said first member and arranged to bias said iner in. member to a po siti n in which said second contact member engages said fixed contact member. means for adjusting the biasing force exerted by said spring. be parts bein c so pro mrtioned that at. all frequencies of oscillations oi said first member above a predetermined treqnency the inertia of said inertia member will said spring nce du 'ing each oscillation ently to open the contact lormcd by said second contact meinliicr and said fixed c-rintaet member for an interval of time which increases as the speed of the body increases, and an clectroresponsive indicating: device controlled by the contact formed by said second contact member and said fixed contact member.

H. Ap nirat-us For indicating the speed of a movable body comprising a first member adapted to be oscillated at a Frequency which varies with the speed of the body, a pivoted inertia member. a fixed contact member carried by said first member, a second contactmember carried by said inertia member a spring carried by said irst member and arranged to bias said inertia member to a position in which said second contact member engages said fixed contact member, means l'or adjusting the biasin; force exerted by said spring. the parts being so proportioned that at all frequencies of oscillation of said irst member above a predetermined l re- (incur-y the inertiav of said inertia. member will stress said spring: once during each oscilia-jinn suliiciently to open the contact formed by said second contact member and said fixed contact member for an inter al of time \vhic increases as the speed of the body increases, and an electroresponsive indicatin; device controlled by the contact- 't'ormed by said second contact member and said fixed contact member and selectively responsive to the proportion of the open time of said contact to a fixed interval of time.

15. In speed responsive apparatus, the combination of a first member operated through successive cycles at different frequencies, an inertia member pivoted on the first member and sustaining from the movement of the first member a secondary motion, and means connecting the inertia member with the first member and constantly urging the two members to a definite relative position with a force derived partly from the movements of the members and tending to produce a critical condition corresponding to a definite frequency of the first member beyond which a cyclic change in the relative positions of the two members takes place.

16. In speed responsive apparatus, the combination of a first member operated through successive cycles at different frequencies, an inertia member pivoted on the first member and sustaining from the movement of the first member a secondary motion, a first contact member carried by the first member, a second contact member carried by the inertia" member, and means con necting the inertia member with the first member and constantly urging the inertia member to the relative position with respect to the first member in which said second contact member engages said first contact member with a force derived partly from the movements of the members and tending to produce a critical condition corresponding to a definite frequency of the first member beyond which a cyclic separation of the two contact members takes place.

17. In speed responsive apparatus, the combination of a first member operated through successive cycles at different frequencies, an inertia member pivoted on the first member and sustaining from the movement of the first member a secondary motion, a first contact member carried by the first member, a second contact member carried by the inertia member, and means connecting the inertia member with the first member and constantly urging the inertia member to the relative position witlf respect to the first member in which said second contact member engages said first contact member with a force derived partly from the movements of the members and tending to produce a critical condition corresponding to a definite frequency of the first member beyond which a cyclic separation of the two contact members take place, the duration of which separation varies rapidly with slight changes in frequency beyond the critical frequency.

In testimony whereof we afiix our signatures.

PER UTNE. RALPH K. CROOKS.

Images