US2433902A

US2433902A - Railway truck

Info

Publication number: US2433902A
Application number: US533525A
Authority: US
Inventors: Henrichsen Knut
Original assignee: North American Aviation Corp
Current assignee: North American Aviation Corp
Priority date: 1944-05-01
Filing date: 1944-05-01
Publication date: 1948-01-06
Anticipated expiration: 1965-01-06

Description

vJan. 6, 1948. I K. HENRICHSEN 2,433,902

RAILWAY TRUCK 4 Filed May 1, 1944 2 Sheets-Sheet 1 INVENTOR. lfnut Henrichsen Attorney Jan. 6, 1948.

K. HENRICHSEN RAILWAY TRUCK Filed May 1, 1944 2 Sheets-Sheet 2 uvmvmn. Kruzt Hem-ichsen Attarney Patented Jan. 6, 1948 RAILWAY TRUCK Knut Henrichsen, Los Angelcs, Calif., assignor to v North American Aviation, Inc.

Application May 1, 1944, Serial No. 533,525

6 Claims. (Cl. 105-182) This invention relates to railway trucks and has as its general object to provide a railway truck having improved means for mounting a car body for swinging movement under lateral loads and for returning thecar body to a center position when such loads are removed.

More specifically th invention aims to provide a railway truck wherein lateral loads on the car body will be translated into swinging movements in which the car body is tilted laterally so as to cause the upper portion of the car body to lean in the direction from which the lateral forces are applied.

Another object of the invention is'to provide an improved wheel mounting and springing arrangement adapted not only to cushion shocks of wheel units Ill each journalled between a pair of knee-action levers II, the latter being pivoted at l2 to the respective ends of a pair of side frame members I3. springing is provided by a pair of coil springs l4 acting against weight from the frame members I3 to the wheel but also to equalize the transmission of weight to the wheel unit.

Another object of the invention is to provide a truck mechanism which is adapted to inhibit lateral rolling movement of one wheel unit with reference to the other.

Another object of the invention is to provide a truck which permits the wheels to shift later-. ally in response to lateral thrusts of short duration (such as those caused by irregularities in the rails) with a minimum resistance to such lateral shifting and which provides for additional shifting, but against increased resistance, to provid for the pendulum swinging of'the body under lateral forces such as those applied when the car is rounding a curve.

A further object of the invention is to provide an improved mechanism for inhibiting hitching movement which would otherwise result from the application of brakes to the wheels.

In one of its modifications, the invention contemplates an arrangement wherein the same unit functions not only as the springing mechanism for absorbing shocks, but also as a stabilizer or roll-inhibiting device.

In the drawings, like reference characters designate similar parts in the several views.

Fig. 1 is a plan view of a truck embodying the invention;

Fig. 2 is a side elevation of the same;

Fig. 3 is a view taken along line 33 of Fig. 1;

Fig. 4 is a plan view of a modified form of the invention;

Fig. 5 is a side elevation of the modified form; and

Fig. 6 is a view taken along line 66 of Fig. 4.

As an example of one form in which the invention may be embodied, I have shown in Figs. 1, 2 and 3 a railway truck comprising a pair units HI.

Lateral rolling action is inhibited by torque rod connections between the respective pairs of links l5, such connections each including a torque rod l6, journalled in the frame members I3, and arms ll rigidly fastened to the respective ends of each torque rod 16 and pivoted to the respective links l5. If one of the wheels of a unit I0 rises above the level of the other, the rod IE will be twisted, tending to bring the other wheels to the same level.

The weight of the car body is transferred to the frame member I3 by a bolster [8 having rocker ends l9 supported upon rollers 20 mounted in the frame members l3. The rocker arms IS in effect provide a pendulum suspension for the car body on a center above the center of gravity thereof permitting the body to sway sidewise under lateral forces such as the centrifugal forces induced in rounding a curve. The rocker ends I9 also function to permit the wheels to shift laterally in response to lateral thrusts of relatively short duration against the wheels (such as those caused by irregularities in the rails). Such short thrusts are accommodated by movement on the rollers 20 of the relatively low inclined surfaces 5| of the rocker, arms 19. Because of the relatively low incline of these surfaces, the resistance to such short thrusts is relatively low, permittin the wheels and the side frame members l3 to readily shift laterally in response to irregularities in the rails while the car body and the bolster l8 are permitted to travel in a straight path, unaffected by such lateral shifting. Where prolonged lateral forces come into play, such as those induced by centrifugal force in rounding a curve, the more steeply inclined surface portions 52 of the rocker ends l9 will ride up on the rollers 20, thus increasing the resistance to the lateral shift to a point where the resistance will balance the centrifugal forces causing the shift. It may be noted at this time that the resistance to the shift is produced by the weight of the, car body which must be lifted as the surfaces 52 ride .up on the rollers 20.

As the surfaces 52 on one side ride up on the rollers 20, the rocker arms I9 on the opposite side will ride downwardly on their corresponding rollers, thus causing the entire car body to tilt above a longitudinal axis which is disposed above the center of gravity of the car body. Because the center of gravity is below the tiltin axis, the car body will always return by gravity to a centered position.

The weight of the car body is transferred to the bolster Ill through a bearing 22, and all radial stresses, such as rolling and pitching forces, are transferred from the car body to the bolster I8 and vice versa, through the bearing 22 and a bearing 23, cooperating with a relatively heavy pin 24 mounted in the bolster I8.

Braking is elfected by internal brakes 25 as of the shoe type, expanded by a cam 26 operated by a lever 2'! and a rod 28. The brake shoes 25 are pivoted upon a head member 29 which is held against rotation by a brake torque rod 30 anchored at 3| to the frame l3. The torque rod 30 is made parallel to the longitudinal axis of the frame [3 in order to avoid the setting up of pitching movement when the brakes are applied.

In the alternate form of the invention shown in Figs. 4, and 6, springing is provided by a torque rod spring [4A, splined to the knee-action levers HA and a torque tube spring MB secured at 32 to the rod [4A and having its ends splined to brackets 33 which are bolted at 34 to the frame. The rod MA, in addition to forming part of the springing mechanism, has the added function of constituting a torque rod connection between the pair of levers IIA, thus to inhibit roll.

The springing mechanism just described functions to cushion shocks in the following manner: Upward movement of a wheel unit Ill causes the arms HA to pivot about the axis of the torque rod 14A, twisting the latter between the ends and the center thereof and causing the center portion to rotate sufiiciently to transmit some of the twisting action to the torque tube I4B at the center thereof, the end of the latter being anchored against twisting movement by the brackets 33.

modification of the invention is the same as that described above, and the same reference characters are used to designate the parts thereof.

The foregoing may be taken as illustrative of one form in which the invention may be embodied, it being my intention to cover in my claims the use of any equivalent arrangement or apparatus.

I claim as my invention:

1. A vehicle truck comprising a frame, two pairs of bell crank levers, each pair being pivoted to opposite sides of said frame, each lever having an outwardly projecting horizontal arm and an upwardly projecting arm, wheel units journaled in the outer ends of said horizontal arms and supporting the same, cushioning means interposed between and resiliently interconnecting the upper ends of said vertical arms of each of said pair of levers, and roll-inhibiting means comprising a shaft journaled in said frame and an arm secured to each end of said shaft, projecting outwardly from said shaft and operatively connected to the vertical arm of one of said bell crank levers.

4 2. A vehicle truck comprising-a frame, wheel mounting levers pivoted to the frame, a shockabsorbing means comprising cushioner springs coaxial with the pivot of said levers and extending from side to side of the frame, each spring including an inner cushioner spring member and a tubular cushioner spring member in which said inner member is received, the ends of one of said members being secured to said wheel mounting levers and the ends of the other of said spring members being anchored in the frame, the central regions of said spring members being secured together.

3. A truck as defined in claim 2, wherein said inner member is in the form of a shaft, the outer ends of which are secured to said wheel mounting arms and wherein said tubular spring member extends through said wheel mounting arms.

4. The truck defined in claim 2, wherein the spring member which is attached to said wheel mounting arms constitutes, in addition to its springing function, a roll-inhibiting device yieldingly standing at all times to maintain the axis of each pair of wheels parallel to the plane of said frame.

5. A vehicle truck comprising a frame, two pairs of bell crank levers, each pair being pivoted on opposite sides of said frame, each lever having an outwardly projecting horizontal arm and an upwardly projecting vertical arm, wheel units journaled in the outer ends of said horizontal arms and supporting the same, cushioning means interposed between and resiliently interconnecting the upper ends of the vertical arms of each pair of levers, and roll-inhibiting means comprising a torsion shaft journaled in said frame and an arm secured to each end of said shaft, projecting outwardly from said shaft and operatively connected to said upwardly projecting vertical arm to pivot therewith.

6. A vehicle truck comprising a frame, pairs of wheel mount levers pivoted to said frame, a shock absorber and.roll-inhibiting means comprising cushioner and torsion spring members extending from side to side of the frame and co-axial with the pivots of each pair of said levers, one of said members being hollow for receiving the other of said members, the ends of one of said spring members being secured to said wheel mounting levers and the ends of the other of such spring members being anchored to the frame, said spring members being secured together at a central portion between the ends thereof.

KNUT HENRICHSEN.

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

UNITED STATES PATENTS Number Name Date 2,043,542 Johnson June 9, 1936 2,250,650 Piron July 29, 1941 2,250,988 Eksergian July 29, 1941 2,253,042 Muchnic Aug. 19, 1941 2,275,153 Ledwinka Mar. 3, 1942 2,286,608 Eksergian June 16, 1942 FOREIGN PATENTS Number Country Date 194,630 Switzerland Mar. 1, 1938