Height adjustable secondary suspension for a rail vehicle

Patent metadata

Field	Value
Publication number	US-10442448-B2
Application number	US-201715453682-A
Country	US
Kind code	B2
Filing date	Mar 8, 2017
Priority date	Mar 8, 2017
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A secondary suspension system for a railcar comprises a chassis, a primary spring, a levelling actuator, a first hydraulic circuit and a secondary spring. The levelling actuator is adapted to be connected to the carbody. A piston shoulder, located at the lower portion of the piston and below an opening in the chassis, reaches farther than the opening so as to be capable of catching the chassis. The secondary spring is at least partially positioned underneath the piston shoulder. The piston is operative to adopt a high position inside the body under a pressure of a hydraulic fluid injected in a lower chamber below a piston head. This makes the piston shoulder abut against the chassis, thereby compressing the primary spring between the body and the chassis without compressing the secondary suspension.

First claim

What is claimed is:

1. A railcar suspension system adapted to be installed between a bogie and a carbody, the railcar suspension system comprising:
a chassis, said chassis having an opening, said chassis being adapted to be connected to the bogie;
a primary spring;
a levelling actuator, said levelling actuator having:
a body, said body being adapted to be connected to the carbody, said primary spring being inserted between said chassis and a spring receiving portion of said body;
a piston, said piston being operative to slide inside said body, said piston having:
a piston rod, said piston rod having a lower portion extending through a bottom of said body and through said opening in said chassis;
a piston head, said piston head being located at an upper portion of said piston rod, said piston head defining an upper and a lower chamber inside said body respectively above and below said piston head;
a piston shoulder, said piston shoulder being located at said lower portion of said piston rod and below said opening, said piston shoulder reaching farther than said opening so as to be capable of catching said chassis;
a first hydraulic circuit, said first hydraulic circuit being connected to said lower chamber; and
a secondary spring, said secondary spring being located on a side of said piston shoulder opposite said piston head,
wherein in use, said piston is operative to adopt a high position inside said body under a pressure of a hydraulic fluid injected in said lower chamber through said first hydraulic circuit so that said piston shoulder abuts against said chassis, thereby compressing said primary spring between said body and said chassis without compressing said secondary spring.

2. The railcar suspension system of claim 1 wherein said primary spring is a coil spring and said secondary spring is an elastomeric spring.

3. The railcar suspension system of claim 2 wherein said opening of said chassis is located substantially centrally in said chassis.

4. The railcar suspension system of claim 3 wherein said body is positioned within coils of said coil spring.

5. The railcar suspension system of claim 4 wherein said spring receiving portion of said body extends radially from said body so as to receive said coil spring.

6. The railcar suspension system of claim 1 further comprising a third spring, said third spring being connected underneath said chassis and being adapted for connection to the bogie.

7. The railcar suspension system of claim 1 wherein said secondary spring is connected directly underneath said piston shoulder.

8. The railcar suspension system of claim 1 wherein said secondary spring is adapted to be connected to the bogie.

9. The railcar suspension system of claim 1 further comprising a second hydraulic circuit, said second hydraulic circuit being connected to said upper chamber, said piston being operative to adopt a low position inside said body under a pressure of a hydraulic fluid injected in said upper chamber through said second hydraulic circuit so that said piston clears said chassis and so that said secondary spring may abut against the bogie and thereby increase an effective spring rate of the railcar suspension system.

10. A railcar comprising:
a carbody;
a bogie, said bogie having a primary suspension;
a secondary suspension system, said secondary suspension system interconnecting said bogie to said carbody, said secondary suspension system having:
a chassis, said chassis having an opening, said chassis being adapted to be connected to the bogie;
a primary spring;
a levelling actuator, said levelling actuator having:
a body, said body being adapted to be connected to the carbody, said primary spring being inserted between said chassis and a spring receiving portion of said body;
a piston, said piston being operative to slide inside said body, said piston having:
a piston rod, said piston rod having a lower portion extending through a bottom of said body and through said opening in said chassis;
a piston head, said piston head being located at an upper portion of said piston rod, said piston head defining an upper and a lower chamber inside said body respectively above and below said piston head;
a piston shoulder, said piston shoulder being located at said lower portion of said piston rod and below said opening, said piston shoulder reaching farther than said opening so as to be capable of catching said chassis;
a first hydraulic circuit, said first hydraulic circuit being connected to said lower chamber; and
a secondary spring, said secondary spring being located on a side of said piston shoulder opposite said piston head,
wherein in use, said piston is operative to adopt a high position inside said body under a pressure of a hydraulic fluid injected in said lower chamber through said first hydraulic circuit so that said piston shoulder abuts against said chassis, thereby compressing said primary spring between said body and said chassis without compressing said secondary spring and thereby bringing said carbody closer to said bogie.

11. The railcar of claim 10 wherein said primary spring is a coil spring and said secondary spring is an elastomeric spring.

12. The railcar of claim 11 wherein said opening of said chassis is located substantially centrally in said chassis.

13. The railcar of claim 12 wherein said body is positioned within coils of said coil spring.

14. The railcar of claim 13 wherein said spring receiving portion of said body extends radially from said body so as to receive said coil spring.

15. The railcar of claim 10 further comprising a third spring, said third spring being connected underneath said chassis and being connected to said bogie.

16. The railcar of claim 10 wherein said secondary spring is connected directly underneath said piston shoulder.

17. The railcar of claim 10 wherein said secondary spring is connected to said bogie.

18. The railcar of claim 10 further comprising a second hydraulic circuit, said second hydraulic circuit being connected to said upper chamber, said piston being operative to adopt a low position inside said body under a pressure of a hydraulic fluid injected in said upper chamber through said second hydraulic circuit so that said piston clears said chassis and so that said secondary spring may abut against said bogie and thereby increase an effective spring rate of the secondary suspension system.

19. The railcar of claim 10 comprising two said secondary suspensions systems, each one of said two secondary suspensions systems being positioned on a different side of said bogie.

20. The railcar of claim 19 comprising two said bogies, each one of said two bogies being positioned at a different end of said carbody.

Assignees

• Bombardier Transp Gmbh

Inventors

• Monette Mario
• Dumoulin Louis
• Lussier Benoit

Classifications

• B61F5/16 Primary

  Centre bearings or other swivel connections between underframes and bolsters or bogies · CPC title

• B61F5/14

  Side bearings · CPC title

• B61F5/22

  Guiding of the vehicle underframes with respect to the bogies · CPC title

• B61F5/02 Primary

  Arrangements permitting limited transverse relative movements between vehicle underframe or bolster and bogie; Connections between underframes and bogies · CPC title

• B61F5/10 Primary

  incorporating fluid springs · CPC title