Abstract In a railway truck a pivot between the truck frame and the cooperating bolster is permitted to have lateral displacement to improve the riding qualities of the truck. The pivot is maintained automatically centered by motor means which oppose centrifugal forces that would displace the pivot, e.g., while the truck traverses a curve, thereby ensuring that lateral displacement is still possible under such conditions. A special design of such a truck is provided with a bolster comprising two parts, designated upper and lower parts, the lower bolster part being pivotally mounted on the truck transom, while the upper bolster part mounts the vehicle body for vertical springing movement; the two bolster parts are connected together by an articulated linkage for lateral arcuate movement about a longitudinal tilting axis under the action of motor means.
A railway truck comprising a truck frame constituted by transversely spaced side frames and transom means extending between the said side frames; at least two wheel and axle assemblies mounted by the frame and on which the truck runs; a bolster frame supported on the truck frame; a truck frame pivot member mounted by the truck frame and engageable with a cooperating bolster frame pivot member mounted by the bolster frame, the pivot members cooperating with one another to constrain the bolster frame for pivoting movement about a generally vertical axis, one of the said pivot members being mounted by its mounting for lateral movement relative to its frame; motor means operatively connected between one of the pivot members and its respective frame and operative to move the pivot member laterally with respect to its respective member, detector means operative with the truck upon the presence of a centrifugal force on the pivot members urging lateral movement of the pivot axis from a center position, and means operative in response to said detector means for actuating the motor means to at least oppose the said force and urge the said pivot axis toward the said center position.
Claim 2
Dependent Claim
197 words
A railway truck comprising a truck frame constituted by transversely spaced side frames and transom means extending between the said side frames; at least two wheel and axle assemblies mounted by the frame and on which the truck runs; a bolster frame supported on the truck frame; a truck frame pivot member mounted by the truck frame and engageable with a cooperating bolster frame pivot member mounted by the bolster frame, the pivot members cooperating with one another to constrain the bolster frame for pivoting movement about a generally vertical axis, one of the said pivot members being mounted by its mounting for lateral movement relative to its frame; motor means operatively connected between one of the pivot members and its respective frame and operative to move the pivot member laterally with respect to its respective member, detector means operative with the truck upon the presence of a centrifugal force on the pivot members urging lateral movement of the pivot axis from a center position, and means operative in response to said detector means for actuating the motor means to at least oppose the said force and urge the said pivot axis toward the said center position.
Claim 3
Dependent Claim
82 words
A truck as claimed in claim 1, wherein the said motor means comprise oppositely operating hydraulic units in operative engagement between the truck frame and the truck frame pivot member, means for supplying operating liquid under pressure to the said hydraulic units, and a reservoir containing operating liquid and gas connected between each hydraulic unit and the said liquid supplying means, whereby the gas in the said reservoirs provides the effect of springs accommodating minor movements of the truck frame pivot member.
Claim 4
Dependent Claim
43 words
A truck as claimed in claim 1, wherein the said motor means comprise opposed hydraulic units comprising respective cylinder members each mounted in a respective truck side frame and having their respective piston members in operative engagement with the truck frame pivot member.
Claim 5
Dependent Claim
79 words
A truck as claimed in claim 3, wherein the said detector means comprises a movement detector member mounted on the truck frame operatively connected between the truck frame pivot member and a truck side frame and providing a corresponding signal upon movement of the truck frame pivot member from the center position, and the means responsive to the detector means comprise servo means receiving the said signal and feeding operating liquid to the said hydraulic units in response thereto.
Claim 6
Dependent Claim
45 words
A truck as claimed in claim 3, wherein the truck frame pivot member is mounted on the transom means for lateral movement relative to the truck frame by opposed longitudinally extending resilient suspension units having their compression axes coincident and disposed longitudinally of the truck.