Snubbed railway vehicle bogie

A bogie for a railway vehicle having a bogie frame carrying axle boxes, which bogie also includes a resilient suspension having two stages namely:

• (a) a primary stage between said bogie frame and said axle boxes, said primary stage consisting of resilient chevron-shaped blocks of high vertical flexibility and transverse rigidity;
• and (b) a second stage between said bogie frame and the vehicle body said second stage having reduced vertical flexibility and high horizontal flexibility, said secondary suspension stage being formed only from interleaved resilient blocks operating in compression, said blocks being distributed about an imaginary center of pivotal movement of said bogie with respect to said body and having an axis of compression which is slightly inclined with respect to said body so as to converge upwardly and to operate in shear to ensure transverse and rotational adjustment of said bogie and reduced inclination of said body on a curved track, and further comprising guide members which receive said axle-boxes and which are connected to said bogie frame by link means, said chevron-shaped blocks associated with said primary stage of said suspension being interposed between said guide members and said bogie frame, and devices to stiffen said primary suspension, each of said devices being associated with one of said link means and with one of said chevron-shaped blocks and comprising a resilient member compressed between said link means and a plate member connected to the said chevron-shaped block so that the stiffness of said resilient member reinforces that of said chevron-shaped block for a truck under tare and with small loads, thereby hardening the primary suspension, the arrangement being such that at higher loads the said resilient member is ineffective, each of said devices comprising further a resilient stop with progressive rigidity, interposed between said link means and a fixed stop borne by said frame at an intermediate point along the length of said link means in order to harden the primary suspension at the highest loads of the truck.

A railway vehicle having a body supported by a bogie having a bogie frame and axle boxes and comprising a two-stage resilient suspension namely:

• (a) a primary stage between said bogie frame and said axle boxes, including resilient chevron-shaped blocks of vertical flexibility and relative transverse rigidity;
• and (b) a second stage between said bogie frame and said vehicle body consisting only of resilient interleaved compression blocks of horizontal flexibility and relative vertical rigidity, wherein said compression blocks are distributed about an imaginary vertical axis of pivotal movement of said bogie with respect to said body and have their axes of compression slightly inclined so as to converge upwardly towards said vertical pivotal axis, said blocks operating in shear to ensure transverse and rotational adjustment of said bogie with respect to said body and to allow a limited inclination of said body on a curved track, and a device adapted to change the transverse characteristics of the second stage of the suspension as a function of the load, and comprising a rigid body stop cooperating with a rigid bogie stop, the latter being coupled to said bogie frame, vertically by means of a first set of resilient blocks and horizontally by means of a second set of resilient conical blocks of progressive rigidity, said resilient blocks mounted on said bogie frame, said rigid body stop and said rigid bogie stop having mutually cooperating oblique surfaces which are spaced apart when said vehicle is unloaded but engaged when said body is loaded, whereby any given transverse movement of said bogie causes greater compression of said second set of resilient blocks when said body is loaded than when it is unloaded.

A railway vehicle having a body supported by a bogie comprising a bogie frame and axle boxes and a two-stage resilient suspension namely:

• (a) a primary stage between said bogie frame and said axle boxes, said primary suspension stage including resilient chevron-shaped blocks of vertical flexibility and relative transverse rigidity;
• and (b) a second stage between said bogie frame and said vehicle body consisting only of resilient interleaved compression blocks of horizontal flexibility and relative vertical rigidity wherein said compression blocks are distributed about an imaginary vertical axis of pivotal movement of said bogie with respect to said body and have their axes of compression slightly inclined so as to converge upwardly toward said vertical pivotal axis, said blocks operating in shear to ensure transverse and rotational adjustment of said bogie with respect to said body and to allow a limited inclination of said body on a curved track, said bogie further including girder members in which said axle boxes are located, and said bogie frame being connected to said girder members by respective ones of said resilient chevron-shaped blocks of said primary suspension stage and by respective links located under said resilient-shaped blocks, and devices to stiffen said primary suspension, each of said devices being associated with one of said link means and with one of said chevron-shaped blocks and comprising a resilient member compressed between said link means and a plate member connected to the said chevron-shaped block so that the stiffness of said resilient member reinforces that of said chevron-shaped block for a truck under tare and with small loads, thereby hardening the primary suspension, the arrangement being such that at higher loads the said resilient member is ineffective, each of said devices comprising further a resilient stop with progressive rigidity, interposed between said link means and a fixed stop borne by said frame at an intermediate point along the length of said link means in order to harden the primary suspension at the highest loads of the truck.