US2099240A

US2099240A - Bolster supporting unit

Info

Publication number: US2099240A
Application number: US759817A
Authority: US
Inventors: Donald F Sproul
Original assignee: Cardwell Westinghouse Co
Current assignee: Cardwell Westinghouse Co
Priority date: 1934-12-31
Filing date: 1934-12-31
Publication date: 1937-11-16
Anticipated expiration: 1954-11-16

Description

Nov. 16,1937. D. F. sPRoUL l 2,099,240

BOLSTER SUPPORTING UIT- Filed Dec. 51. 1934 b/mld 177.30710@ 55 break or otherwise injure the frame.

Patented Nov. i6, 1931 UNITED s'lares PAfir-altrfrorFlcl-zA l aww-j,

'nomia F. smul, chicago, n1., mmmto Card well-Westinghouse Company, a corporav on of Delaware I Appummnpeinber 31. isscserm 10.159.811 l 9Clalml.

One of the objects of the invention is the provision of a new and improved spring unit having novel means for resisting the compression of the.

unit. l Another object of the invention is the provision of a new and improved spring unit having novel means for preventing harmonic vibration of the unit in use.

A further object of the invention-is the provision oi' a new and improved spring unit of the dimensions of a conventional helical railway bolster spring'but with greatly increased capacity.

Another object' of the invention is the provision oi' a spring unit adapted for supporting` a railway bolster that is simple in construction, emcient in operation, that is'adapted to be substituted for a conventional helical bolster spring and which is not likely to become broken or get outoi'-repair.

Other and further objectsy and advantages of the invention will appear from the following description taken in connection with the accompanying drawing, in which: i

Fig. 1 is a side elevation of a railway truck with parts broken away and parts omitted for thesake of clearness; v 30 Fig. 2 is a vertical section of the bolster supporting unit;

Fig. 3 is a section on the broken line 3 3 of Fig. 2; and 1 f Fig. 4 is a section similar to Fig. 3 but showing the unit compressed.

I In spring suspension for railway freight cars,

it is common practice to employ a spring assembly of helical springs for supporting each end of the bolster` 4from the truck frame. The helical'type of spring is eminently satisfactory so far as its functioni of resiliently supporting the weightoi the car is concerned, but it has the disadvantage that it is subject to harmonic vibration. In other words, under certain conditions, as when the ends of the rails become slightly elevated or depressed or where the wheels` haveilat portions on their peripheries of the wheels to synchronize with the periodic vibration of the spring assembly, the j vibrations will build up to `such an extent that the car if heavily loaded may damage the springs by causing themtogo `solid and in doing so to Instances are known where this harmonic vibration has built up to such an extentas to cause the car to become derailed. Furthermore, the building of freight cars with progressively increasing sizes Vand weights fhas necessitated the use oi' springs of 5 greater and greater capacities. But the small space allotted to the springs by car builders creates a serious problem for the 'spring designer to providethe desired spring capacity in the required space. Y "I'he present invention is designed to 4overcome these dilculties by providing a spring unit that may be substituted for one or more of the helicals in a conventional bolster supporting` spring assembly, that has the desired capacity and is provided with novel means for preventing harmonic action of the assembly. A Referring'now tothe drawing, the reference character lil designates a portion of a railway truck I2 comprising a side frame Il having a 2o bolster opening therein through which the end of the bolster I3 extends. A spring plank I4 extends through the opening and a spring assembly designated generally by the reference character I5 is inserted beneath the bolster and rests on the spring plank for resiliently supporting the bolster. Since the specific construction of the side frame and bolster constitute no part of the present invention,itis not thought necessary to furtherillustrate or describe the same. The spring assem- 30 bly I5 comprises upper and lower spring plates IB and Il between which are helical springs I8, one of which is 'shown in Fig. 1, and one or more spring units I9. The spring unit I9 is so designed as to increase the capacity of the spring assembly and prevent harmonic vibration thereof. l

In the form of the device shown, a cylinder' 2| is provided having a bottom wall or base 22 which is preferably circular and provided `with upwardly extending ns or ribs 23 that may be, 40 and preferably are, integral with both the base and side ofthe cylinder. The inner ends of the ribs 23 are integral with a circular plate 24 which has an axial opening 25 therethrough. The upper portion of the plate about the opening is beveled to constitute a valve seat for a ball valve 26. 'I'he plate 24 is concave and is provided with an upwardly extending'peripheral portion 21 which f is beveled on its inner edge, as at 28, to form a valve seat, as will presently appear. v 50 A hollow piston 29 is fitted within the cylinder 2i. This piston constitutes the supporting portion of the unit and telescopes within the cylinder 2l. Suitable means are provided for limiting the outward movement of the piston relative to the cylinder. In the form of construction shown.

the piston is provided with a plurality of .periphf eral grooves 3i extending longitudinally of the cylinder wall and a set screw 32 secured in the upper end of the cylinder '2| and provided with a projection 33 engaging 'in the groove 3| is sdafpted to prevent withdrawal of the piston from the cylinder. The piston 29 is provided with an auxiliary piston 34 which extends downwardly axially of the base or .supporting end wall 3l of the piston 29. This piston is adapted to telescope into an auxiliary cylinder or valve memberll, the lower end of which is provided with an extension 31 having a beveled surface 34 for seating on the bevelled surface 26 of the plate 24. The ex-A tension 31 overhangs or projects inwardly beyond the inner edge of the upwardly extending -portion 21. The auxiliary cylinder 33 is provided adjacent its lower end with a flange 3l which constitutes a seat for a spring 4l which encircles the sleeve 36 and engages the top plate 33. 'I'his spring is adapted to return theparts to extended position after compression. "I'he piston 23 and the auxiliary piston 34 are provided with suitable piston rings or packing 42 and 43, respectively.

`When the parts are assembled, the cylinder 2| is partially filled with a liquid, preferably above the level of the diaphragm 46 when the unit is in extended position, and in the operation of the device when the unit is compressed.

the liquid in the auxiliary cylinder or valve mem- I pacity of the unit will be less than .the unit shownand vice versa.

When it is desired to increase the capacity of the spring assembly, it may be done in one of: two ways, either by substituting additional 'units for the helicals or by employing units in which the overhanging extension31 is reduced,

Suitable means are provided for cushionin the initial compressive forces which may be re-` ceived on the plate 35 while in service. Any suitable mechanism mayI be employed for this service. In the form of construction shown, a spring plate is used. As shown in Figs. 2 and 3,

the piston 34, which is provided with a bottom` wall 44, has its side wall extended downwardly beyond said wall and provided with an annular shoulder 45 against which a spring plate 46 is clamped, as by means of the annular clamping member 41.

In operation, a downward thrust movement oi the auxiliary cylinder 34 will be initially cushioned' by the resilience of the plate 46 which is permitted a slight movement before it comes in contact with the projection or seat 43 on the bottom wall 44 of the piston 34.

The parts are so arranged and proportioned that slightly before or slmultane0usly with the seating of the plate 46 on the projection 43 the valve member 36 will rise to permit the escape of the liquid into the outer cylinder. Upon rebound the valve member 36 will seat and the liq- Yber '30.

uid will be returned by suction and gravity 'past the valve 23 into the inner cylinder or valve mem- A bar 40 within the-sleevev member 34 limits the upward movement of the valve and retains it in proper position. 'y

In practice, one or more offthe conventional lhelical springs are replaced by one or 'more of the units and in order to properly equalize the resistance to the downward .movement of the bolster and prevent turning bf the same. the units are. symmetrically arranged. For instance, if only two of the unitsare employed for, each bolster, one is located at the end of the bolster on the forward side, and the other at the opposite end of the 4bolster on vthe rearl side.

It is thought from the foregoing taken in con. nection with the accompanying drawing that the construction and operation of my device will be apparent to those skilled in the art, and that changes in size, shape, proportion anddetails oi' construction may be 'made without departing from the spirit and scope of the appended claims. e

I claim as my inventionzj 1. In a spring suspension for railway cars, a main cylinder for containing a liquid, an auxiliary cylinder within said main cylinder and containing a liquid, a spring surrounding said' auxiliary cylinder and adapted to assist in supporting a car, and means including said spring for controlling the transference oi liquid from said auxiliary to said main cylinder upon compression of said unit.

2. In a spring unit for railway car spring suspension, a primary cylinder adapted to contain a liquid, 'said cylinder having a closed lower end provided with a plate member held in spaced relation to' the bottom and side walls of thesaid plate having an axial opening and a valve seat on its peripheral edge, a hollow piston, an open- -ended cylinder within said primary cylinder having an extension on one end engaging said seat and overhanging the same', a spring for resisting the movement of said piston and the unseating' of said open-ended cylinder and an inner piston for saidlast-named cylinder movable with said first-named piston.

3. In a spring unit for railway carfspring sus-- pension, a primary cylinder adapted to contain a liquid, said cylinder having a closed lower end provided with a plate member held in spaced relation'- to the bottom and side walls of the said plate having an axial openingand a valve seat on its peripheral edge, a hollow piston, an openended cylinder within said primary cylinder having an extension on one end engaging said seat and overhanging the same, a spring for resisting the movement of said piston and the unseating of said coen-ended cylinder, and a resilient metal plate carried by said hollow piston for cushioning the initial compressive forces delivered to said unit.

4. A spring unit 'for car spring suspension, comprising a pair of telescopic members adapted to contain a liquid, a pair of telescopic elements within said members adapted to contain a liquid, one of said members having a valve seat on which one of said elements is adapted to seat, and a spring for yieldingly resisting the compression oi' said unit and the unseating of said element.

5. A spring unit comprising a pair of telescopic members, a pair of elements defining a space within said members for containing a liquid, said space being at its maximum when said members are extended and at its'minimum when they are compressed, means including one of said elements for controlling the ilow of liquid from -said elements in to said members when said unit is 'compressed, and a vaived passage through which said vliquidis returned when said unit is expanded.

6. A spring unit comprising compressible members 'adapted to contain a liquid. compressible means within said members adaptedto contain a liquid and to be compressed for discharging liquid therefrom into said members when said lunit is compressed, and means including a spring for controlling the iiow oi liquid from said compressible means to said'members when saidy unit is compressed, said spring returning said members to extended position after compression.-

. 7. In a spring suspension for railway cars, a

.spring unit comprising' a reservoir, a cylinder movable relative to Asaid reservoir and adapted to receive a liquid therefrom when the 4unit expands. a piston for said cylinder, a resilient sup-` v porting member for resisting the compression of said unit, means including said cylinder for placing said reservoir in communication with said cylinder for receiving liquid iromkthe cylinder when said unit is compressed, and hydraulic mechanism comprising a valve controlled by saidmember for resisting the compression oi said mit ' inward flexing movement.

`8.'In a railway car. a truck'irame, bolster, a spring assembly for supporting said bolster from said trame, said assembly comprisstruck' ing helical springs and a spring unit operating in parallel. said unit comprising hydraulic mechanism and a vresilient supporting member, said mechanism including a cylinder. a reservoir surrounding said cylinder and containing a fluid, a pressure valve and a check valve 'oi' restricted area for controlling the ilow oi said iluid between 'said reservoir and cylinder for dampening bothl the compression and expansion movementoi said 9. A spring unit -ior railway car spring suspension, comprising a resilient supporting memberand hydraulic mechanism for controlling the compression of said unit, said mechanism comn oNAm r'. amour.