US2631025A - Successively operated speeder springs for speed governors - Google Patents

Description

March 10, 1953 H. L. BONE SUCCESSIVELY OPERATED SPEEDER SPRINGS FOR SPEED GOVERNORS S 2 SHEETSSHEET 1 Filed Sept. 30, 1948 INVENTOR. [fer art 1. E0119.

HIS ATTORNEY m ar a M Insulation March 10, 1953 H. L. BONE 2,631,025 SUCCESSIVELY OPERATED SPEEDER SPRINGS FOR SPEED GOVERNORS Filed Sept. so, 1948 2 SHEETSSHEET 2 fiwfi g 8 g 8 T313685? o n 71. J ,4 65 4 45 M a F INVENTOR. Herfiert L. Bone Fly: BY

H18 ATTORNEY Patented Mar. 10, 1953 SUCCESSIVELY OPERATED SPEEDER SPRINGS FOR SPEED GOVERNORS Herbert L. Bone, Forest Hills, Pa., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania Application September 30, 1948, Serial No. 52,095

2 Claims.

My invention relates to speed responsive devices, and especially to speed responsive devices, which are adapted for use on a locomotive.

One object of my invention is to provide an improved speed responsive device which will perform a series of control functions at widely separated speeds.

Another object is to provide an improved spring loading arrangement for a centrifugal speed responsive device, which is adapted to make the centrifugal speed responsive device effective over a wide range of speeds.

A further object is to provide improved means for setting two different speed schedules at which a speed responsive device is to perform a series of control functions, and improved means for .selectively shifting the speed responsive device from one schedule to the other.

Another object is to provide, in a speed responsive device for use on a locomotive, improved means for separately establishing different speed schedules at which the device is to operate when the locomotive is used in freight and passenger service, and improved means for shifting the device between its freight and passenger schedules.

Another object is to provide, in a speed responsive device of the type described, improved means for separately adjusting each speed at which a control function is performed on each speed schedule.

Another object is to provide an adjusting mechanism for a speed responsive device in which each speed adjustment is made by moving an adjusting member with respect to a stationary support.

Another object is to provide an improved speed responsive device of the type described in my copending application for Letters Patent of the United States, Serial No. 631,161, filed November 27, 1945, now Patent No. 2,606,753, for Speed Responsive Devices.

I accomplish the foregoing and other objects of my invention by providing in a governor having centrifuge members moved by centrifugal force, two springs having different spring rates and arranged in tandem to oppose the movements of the centrifuge members. Because of the dif ferent rates of the two springs, the initial movement of the centrifuge members compresses the weaker spring, without substantially changing the compression of the stronger spring. After a predetermined movement of the centrifuge members, a retainer for the stronger spring is picked up, and further movement of the centrifuge members compresses only the stronger spring, without applying any additional stress to the weaker spring. I may also provide a third spring which may be picked up in parallel with the stronger of the two tandem springs to increase still further the spring rates opposing the movement of the centrifuge members.

I provide a plurality of electrical contacts which are operated sequentially at low, medium, and high speeds by the speed responsive device. Each contact comprises a movable contact finger arranged to be moved by the centrifuge member and a cooperating stationary contact finger. The contact fingers of each pair are biased toward each other so that the fingers engage. As the speed increases, the movable fingers are moved away from the stationary fingers by the speed responsive device. The stationary fingers follow the movable contact fingers at first, but this following movement of the stationary fingers is limited by a novel adjustable stop mechanism. This stop mechanism includes a bracket spanning all the stationary fingers and carrying two groups of set screws. One group of set screws is aligned with the laterally spaced contact fingers while the other group lies between them. By shifting the bracket endwise, the other group of set screws may be aligned with the contact fingers, while the first group is moved between them. The bracket is mounted on a stationary support so as to be readily adjustable endwise. The bracket may be locked in either position, so that adjustment of any set screw can be made when the bracket is stationary. Each group of set screws determines a schedule of speeds at which the contacts are opened by the speed responsive device. Each individual set screw independently determines the speed at which one particular contact is opened on one particular schedule.

In the drawings, Fig. l is a view of one form of speed responsive device embodying my invention, partly shown in top plan and partly taken in section on the line I-I of Fig. 3, looking in the direction of the arrows. Fig. 2 is a cross-sectional view of the device of Fig. 1 taken on the line II-II of Fig. 3, looking in the direction of the arrows. Fig. 3 is a left-hand view of the device of Figs. 1 and 2 with the cover removed, showing the contact structure. Fig. 4 is a detail View, on an enlarged scale, of the spring loading arrangement in the device of Fig. 1.

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

The speed responsive device in the form here shown is particularly suitable for application to cars or locomotives in which the axles have outboard bearings, and comprises a housing I which is adapted to be bolted to an axle journal box by means of bolts 2. The housing I is divided by means of a partition 3 to form an inner compartment 4 which houses the centrifuge assembly, and an outer compartment which houses the electric circuit controlling contacts of the device. The compartment 4 is closed at the end adjacent to the journal box by means of an end plate 6, while the contact compartment 5 is closed at its outer end by a removable cover 1.

The centrifuge assembly comprises a rotor S which is rotatably supported at one end in axial alignment with the car axle by means of a ball bearing 9 mounted in the end plate 6, and at the other end in a ball bearing I9 mounted in an annular flange Ii formed on the partition 3. An oil seal I2 is provided adjacent the inner side of the ball bearing 9, and an oil seal I3 which acts as a grease retainer is likewise provided at the outer side of the ball bearing II]. The rotor 8 is made up of two separate parts 8a and 8b bolted together, and is adapted to be driven from the axle by suitable driving mechanism here shown as including a drive shaft I4 operatively connected at one end with the axle and at the other end with the rotor. This drive mechanism forms no part of my present invention, and need not, therefore, be described in detail herein.

Two centrifuge members i5 and I6 are pivotally attached to the rotor by means of pivot pins I1 and I8 which extend at right angles to, and are equally spaced from the axis of rotation of the rotor. The operating arms I55! and I6a (see Figs. 2 and 4) of these centrifuge members are operatively connected at their inner ends with a push rod I9 by means of gear teeth which extend into and cooperate with toothed recesses provided in the push rod I9. The push rod is mounted for longitudinal sliding movement along the axis of the rotor by means of spaced bushings 29 and 2I provided in the rotor.

The push rod I9 is provided with portions I9a and I9?) (see Fig. 4) of different diameters, separated by a shoulder I90. At the opposite end of the wider portion I9b from shoulder We is another shoulder I 9d. A sleeve 22, slidable on the smaller portion I9a, is provided with a flange 22a which extends outwardly beyond the portion I9b. A spring 23 is retained between shoulder I 901 and the flange 22a. A second spring 24, having a substantially greater spring rate than spring 23, is retained between the opposite side of flange 22a and a retainer 25 formed on the part 8a of the rotor 3. The push rod I9 also cooperates under certain conditions with a third coil spring 25 which abuts. at one end against one end wall of the part 8a of the rotor and at the other end against a thrust washer 21. The washer 21 is free to move between a shoulder 29 formed on the part 8a of the rotor and two stop lugs 29 provided on the part 812 of the rotor.

The springs 23 and 24 cooperate to bias the push rod to its right-hand extreme position as viewed in Fig. 1, so that the centrifuge weights are swung to their inner extreme positions. Since the spring 24 has a substantially greater rate than spring 23, the latter spring takes up by its compression substantially all the initial 4 loading of both springs, and the spring 24 is compressed only slightly from its free length.

If under these conditions the rotor 8 starts to rotate and its speed continuously increases, the centrifuge members I5 and I6 move outwardly, thereby moving push rod I9 to the left as it appears in the drawing. At first this movement of rod I9 to the left is resisted substantially only by the light spring 23, since spring 24 is not compressed substantially because of its greater spring rate. As the push rod I9 continues to move to the left, shoulder I engages sleeve 22 and thereafter spring 23 is not compressed further. Continued movement of push rod I9 then takes place against the compressive force of spring 24 alone. The push rod I9 moves against spring 24 alone until shoulder I9d engages thrust washer 21, whereupon further movement of the push rod is resisted by both springs 24 and 26. Push rod I9 may continue to move to the left until thrust washer 21 engages shoulder 28, whereupon further movement of the push rod is stopped.

It is well known that centrifugal force increases as the square of the angular velocity. By increasing the total rate of the springs opposing the movement of the centrifuge members as their travel increases, I compensate for the inherent non-linear increase in centrifugal force so as to obtain approximately a linear relationship between the speed of the drive shaft I4 and the travel of push rod I9.

The left-hand end of the push rod I9 is provided with an antifriction thrust bearing 30. The inner race of the bearing 30 is secured to the reduced end of push rod I9 by means of a snap ring 3I. The outer race of bearing 39 is secured within a rectangular bearing housing 32 having a top plate 33 covering the end of the bearing. The housing 32 is held against rotation by a bearing stop 34 in the form of an L- shaped plate fastened to the partition 3. The top plate 33 engages a hardened steel bar 35 (see Fig. 2) secured to an insulating member 36 which latter in turn is riveted to a plurality of movable contact fingers 31, 38, 39, and 40, respectively. These movable contact fingers and two additional fingers 4I and 42 are secured by means of terminal posts 43, 44, 45, 46, 41 and 48, respectively, to an insulating support 49 attached to bosses 50 formed on the partition 3. The movable contact fingers 31 to 42 cooperate with fixed contact fingers 31a to 42a, respective-. ly, to form associated contacts 31-31a to 42- 42a. The fixed contact fingers are riveted at their free ends to associated supporting brackets til, 52, 53, 54, 55, and 56 secured by means of terminal posts 51, 58, 59, 60, BI, and 62 to the insulating support 49.

A shifter bracket 93 is adjustably mounted at its ends on the insulating support 49, and extends at right angles to and spaced from the stationary contact fingers 3111-4217.. The shifter bracket 63 carries two groups of set screws 64 and 65. provided with a lock nut'fifi. The ends of the shifter bracket 93 are slotted, as at 63a, to receive studs 61 which project from the insulating support 49. Lock nuts 98 on the studs 61 retain the shifter bar 63 in any position to which. it is adjusted with reference to the support 49. A pair of angle brackets 99, attached to the support 49 by means of bolts 10, cooperate with the.

Each of the set screws 64 and 65 is studs in supporting and guiding the movement of the shifter bracket 63.

Above the right end of the shifter bracket 63, as it appears in Fig. 3, two letters F and P are impressed in the upper surface of the support 49 in any suitable manner. The shifter bracket 63 carries on its upper surface a bracket H which overlies the letter F when the parts are in the position shown in the drawing. The letter F is therefore visible when the cover 1 is removed, and indicates that the speed responsive device is set to open its respective contacts according to a schedule established for a locomotive in freight service.

By loosening the lock nuts 68, the shifter bracket 63 may be moved endwise to the left from the position shown in the drawing until the studs 6'! engage the opposite ends of the slots 53a. The parts are so proportioned that when the bracket 63 is so shifted, the set screws 64 are moved out of alignment with the stationary contacts 3'lad2a, and the set screws 65 are moved into alignment with those contacts. At the same time, the bracket H moves to uncover the letter P and cover the letter F,.thereby indicating that the speed responsive device has been set for a schedule of speeds suitable for a locomotive in passenger service.

Each contact finger of each cooperating pair is biased to engage its opposite contact, finger. Attached to the terminal posts 43-48 associated with the movable contact fingers are brackets 72, one for each movable contact finger, which brackets extend parallel to and spaced from the contact fingers. Retained between each bracket "52 and its associated movable contact finger is a coil spring 73. These coil springs 13 bias the movable contact fingers toward the stationary contact fingers. The coil springs I3 associated with the four central contact fingers 31, 38, 39,

it, which are attached to insulating member 3t and steel bar 35, also serve to bias the steel bar 35 into engagement with the bearing top plate 33 on the end of push rod 19.

The flexible stationary contact fingers 3'la42a are self-biased toward their respective movable contact fingers. The proper bias may be established and adjusted in the case of each stationary contact finger by properly bending the end of the bracket 53 which supports the contact finger. sulating tips M which at times engage the respective stationary contacts 3'Ia42a and limit their movement toward the movable contact fingers.

The setting of any set screw 64 or 65 determines the speed at which its associated pair of contact fingers open. For example, referring to Fig. 2, it may be seen that as the speed of the locomotive increases and the push rod 89 moves to the left, the speed at which the contacts 39--39a separate is determined by the point at which the motion of contact 38a is stopped by the adjustment of set screw 84.

When the shifter bracket 63 is in its freight position, as shown in the drawing, the speed at which any given contact is opened is determined by the setting of its particular set screws 64. As indicated by the letters L, M, and H in Fig. 3, the contacts 3838a and 3939a are arranged to open at a relatively low speed, the contacts ill-Sic and Ail- 512a. at a medium speed, and the contacts ll- 51a and 4242a at a high speed, When the shifter bracket 63 is moved to its passenger position, an entirely new and inde- The set screws 64 and 65 carry inpendent schedule of contact opening speeds is then established, which schedule is determined by the setting of the set screws 65 and is entirely independent of the settings established by the set screws 64.

It should be noted that the outer movable contact fingers 4| and 42, which are the high speed contact fingers, and not rigidly attached to the insulating member 36 in the same manner as the other movable contact fingers 31-40. Instead, the member 36 is provided with recesses 38a (see Fig. 1) in alignment With the contact fingers M and 42. Because of this construction, the fingers 4i and 42 are engaged and deflected from their normal position only when a certain high speed is reached, approaching the speed at which the contacts 4! and 62 are to be separated from their respective stationary contacts. This construction avoids excessive deflection of the stationary contact fingers Ma and 42a which would occur when the speed responsive device was stationary if the fingers 4i and 42 were rigidly attached to the member 36.

Operation The parts are shown in the drawings in the positions they assume when the speed responsive device is stationary. Let it be assumed that the locomotive on which the device is mounted starts and continuously increases its speed. As the speed increases, the centrifuge members it move outwardly, and move the push rod 19 to the left, as it appears in Fig. 1. This movement is opposed by the tandem springs 23 and 26. Because of the difference in the rates of these two springs, the initial movement of the push rod [9 compresses the weaker spring 23, without substantially compressing the spring 24. When the push rod I9 has moved far enough so that the shoulder I engages sleeve 22, then the weak spring 23 is not further compressed, but additional movement of the push rod 19 is opposed only by the spring 24. As the leftward movement of push rod i9 continues with increasing speed, the outer edge of shoulder I9d picks up the inner edge of thrust washer 21, and thereafter the motion of the push rod I9 is opposed by both springs 24 and 26 acting in parallel. If the speed continues to increase until thrust washer 21 engages shoulder 28, then the push rod l9 does not move further.

During this leftward movement of the push rod l9 occasioned by the increasing speed, the four central movable contacts 37, 38, 39, and iii move together, separatin from their respective stationary contacts at the speeds determined by the setting of the set screws 64. As the speed continues to increase, the recesses 36a on the member 36 engage the movable contact fingers 4i and 42 and thereafter these fingers move together with the other movable contact fingers 31-40. The contact fingers 4| and 42 separate from their respective stationary contact fingers at the speeds determined by the setting of their associated set screws 64. As described above, the shifter bracket 63 may be shifted so that set screws 55 determine ilze contact opening speeds instead of set screws Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Havin thus described my invention, what I claim is:

1. Speed responsive apparatus, comprising a rotatable member, centrifuge means connected to said member for rotation therewith, a push rod connected to said centrifuge means so as to be translated concurrently with radial movement of said centrifuge means, said push rod having adjacent portions of different diameters separated by a first annular shoulder, a second annular shoulder at the opposite end of the larger diameter portion from said first shoulder, a sleeve slidable on said smaller diameter portion of the push rod having a flange extending outwardly beyond said first shoulder, a retainer fixed against translatory movement and encircling said push rod, a first coil spring encircling the push rod and retained between said second shoulder and said flange, a second spring having a substantially greater rate than said first spring encircling said push rod and retained between the opposite side of the flange and the fixed retainer, a retaining washer arranged for translatory movement with respect to said first retainer and having its inner edge aligned with the outer edge of said second shoulder, a stop for limiting the movement of said retaining washer, and a third spring encircling the push rod and retained between said retaining washer and said retainer, said centrifuge means and push rod being effective upon a continuous increase in speed of said rotatable member first to compress said first spring until said first shoulder engages said sleeve, then to compress said second spring alone until the outer edge of said second shoulder engages the inner edge or" said retaining washer, and then to compress both said second and third springs simultaneously until said retainer washer abuts said stop, whereupon motion of said centrifuge means and said push rod is stopped.

2. Speed responsive apparatus, comprising a rotatable member, centrifuge means connected to said member for rotation therewith, a push rod connected to said centrifuge means so as to be translated concurrently with radial movement of said centrifuge means, said push rod having adjacent portions of different diameters separated by a first annular shoulder, a second annular shoulder at the opposite end of the larger diameter portion from said first shoulder, a sleeve slidable on said smaller diameter portion of the push rod having a flange extending outwardly beyond said first shoulder, a retainer fixedagainst translatory movement and encircling said push rod, a first coil spring encircling the push rod and retained between said second shoulder and said flange, and a second spring having a substantially greater rate than said first spring encircling said push rod and retained between the opposite side of the flange and the fixed retainer, said centrifuge means and push rod being effective upon a continuous increase in speed of said rotatable member first to compress said first spring until said first shoulder engages said sleeve, and then to compress said second spring.

HERBERT L. BONE.

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

UNITED STATES PATENTS Number Name Date 1,180,720 Howe Apr. 25, 1916 1,996,679 Lepek Apr. 2, 1935 2,009,995 Engel Aug. 6, 1935 2,200,459 Thomas May 14, 1940 2,211,554 Bone Aug. 13, 1940 2,213,824 Seeley Sept. 3, 1940 2,259,693 Hogeman Oct. 21, 1941 2,281,222 Baierlein Apr. 28, 1942 2,312,212 Edwards Feb. 23, 1943 2,347,834 Livingston May 2, 1944 2,380,963 Greenman Aug. 7, 1945 2,393,375 Hines Jan. 22, 1946 2,418,373 Spaller Apr. 1, 1947 2,426,840 Nye Sept. 2, 1947

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