Coupler head for a coupler assembly of a multi-car rail vehicle, coupler assembly, and method of retrofitting a coupler head with a safety device

Abstract

A coupler head for a (Janney) coupler assembly of a multi-car rail vehicle comprises a coupler head body, a knuckle pin and a knuckle which is rotatable about the knuckle pin relative to the coupler head body between a coupled position and an uncoupled position. A first lock is configured to prevent rotation of the knuckle when the knuckle is in the coupled position. A second lock is configured to prevent rotation of the knuckle when the knuckle is in the uncoupled position. The second lock is further configured to unlock when a predetermined force, which acts on the knuckle so as to rotate the knuckle toward the coupled position, is exceeded, so that the second lock no longer hinders rotation of the knuckle toward the coupled position.

1 . A coupler head for a coupler assembly of a multi-car rail vehicle, comprising:
 a coupler head body, a knuckle configured for cooperating with a corresponding knuckle of another coupler head, and a knuckle pin having a knuckle pin axis, wherein the knuckle pin is mounted to the coupler head body and the knuckle is mounted to the knuckle pin so that the knuckle is rotatable about the knuckle pin axis relative to the coupler head body between a coupled position and an uncoupled position,   a first lock which is configured to be moved, when the knuckle is in the coupled position, into a locking position in which it prevents rotation of the knuckle about the knuckle pin axis toward the uncoupled position, and   a second lock which is configured to prevent, when the knuckle is in the uncoupled position, rotation of the knuckle about the knuckle pin axis toward the coupled position, wherein the second lock is further configured to unlock when a predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position, is exceeded, so that the second lock no longer hinders rotation of the knuckle about the knuckle pin axis (A) toward the coupled position.   
     
     
         2 . The coupler head of  claim 1 , wherein the second lock is configured to connect the knuckle to the coupler head body and keep the knuckle in a predetermined relative position with respect to the coupler head body when the knuckle is in the uncoupled position. 
     
     
         3 . The coupler head of  claim 1 , wherein, when the knuckle is in the uncoupled position and the second lock is in a state in which it prevents rotation of the knuckle about the knuckle pin axis toward the coupled position, the second lock is visible from outside the coupler head. 
     
     
         4 . The coupler head of  claim 1 , wherein, when the knuckle is in the uncoupled position and the second lock is in a state in which it prevents rotation of the knuckle about the knuckle pin axis toward the coupled position, the second lock is accessible and unlockable from outside the coupler head without a need to disassemble the coupler head. 
     
     
         5 . The coupler head of  claim 1 , wherein the second lock is arranged on a top side of the coupler head. 
     
     
         6 . The coupler head of  claim 1 , wherein at least a part of the second lock is configured to deform when said predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position, is exceeded. 
     
     
         7 . The coupler head of  claim 1 , wherein the second lock comprises a locking element which is configured to break when said predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position, is exceeded. 
     
     
         8 . The coupler head of  claim 7 , wherein the locking element comprises at least one of:
 a breaking portion which, when said predetermined force acting on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position is exceeded, is configured to break, wherein at least said breaking portion of the locking element is made of bronze or stiff polymer, and   a locking pin which is configured to, when the knuckle is in the uncoupled position, engage into at least one hole, thereby preventing the rotation of the knuckle about the knuckle pin axis toward the coupled position, wherein the locking pin is removable from the at least one hole without breakage of the locking pin, in order to unlock the second lock.   
     
     
         9 . The coupler head of  claim 8 , wherein the locking element comprises a locking pin which is configured to, when the knuckle is in the uncoupled position, engage into at least one hole, wherein the at least one hole comprises a first hole provided in the coupler head body and a second hole provided in the knuckle, and wherein the locking pin is configured to, when the knuckle is in the uncoupled position, simultaneously engage into both the first hole and the second hole and break when said predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis (A) toward the coupled position, is exceeded. 
     
     
         10 . The coupler head of  claim 9 , wherein the coupler head comprises at least one of:
 the locking pin having a weakened portion configured to break when said predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis (A) toward the coupled position, is exceeded, wherein, when the locking pin engages into the first and second hole, the weakened portion is located between the first hole and the second hole,   the second lock further comprising a resilient safety element providing a resilient force, wherein the resilient safety element is fixedly connected to one of the coupler head body and knuckle and configured to engage, when the knuckle is in the uncoupled position, with the locking pin so as to prevent removal of the locking pin from the first and second hole, and wherein the resilient safety element is further configured to be disengaged from the locking pin by acting on the resilient safety element against the resilient force so as to allow removing the locking pin from the first and second hole, or   a locking pin holder provided on the coupler head body, knuckle or knuckle pin, wherein the locking pin holder is configured to hold the locking pin when the locking pin is in a state removed from the first and second hole.   
     
     
         11 . The coupler head of  claim 7 , wherein the locking element further comprises a plunger to which the locking pin is connected, wherein the plunger is detachably connected to one of the knuckle and coupler head body and the at least one hole is arranged on the respective other one of the knuckle and coupler head body, wherein removal of the locking pin from the at least one hole without breakage of the locking element requires detaching the plunger from the knuckle or coupler head body, respectively. 
     
     
         12 . The coupler head of  claim 11 , wherein the coupler head comprises at least one of:
 the plunger configured to, once detached from the knuckle or coupler head body, be reconnected thereto, in a manner which does not hinder rotation of the knuckle about the knuckle pin axis toward the coupled position, by turning the plunger about 180° and reattaching it at connection points which are identical to connection points prior to the detachment,   the locking pin having a weakened portion configured to break when said predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis (A) toward the coupled position, is exceeded, wherein, when the locking pin engages into the at least one hole, the weakened portion is located outside the at least one hole between the plunger and the at least one hole,   an elastomeric or rubber sleeve provided between an outer surface of the locking pin and an inner surface of the at least one hole when the locking pin engages into the at least one hole, or   the at least one hole being a flag hole of the knuckle.   
     
     
         13 . The coupler head of  claim 1 , wherein the second lock comprises a resilient element and a locking element, wherein the resilient element is arranged to provide, when the knuckle is in the uncoupled position, a resilient force urging the locking element into a locking position in which the locking element prevents the rotation of the knuckle about the knuckle pin axis, and wherein the locking element is arranged to move, when said predetermined force acting on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position is exceeded, out of the locking position against the resilient force of the resilient element. 
     
     
         14 . The coupler head of  claim 13 , wherein the coupler head comprises at least one of:
 the resilient element of the second lock attached to one of (a) the coupler head body or the knuckle pin, or (b) the knuckle, and wherein the locking element of the second lock is configured to engage, when the knuckle is in the uncoupled position, with the respective other one of (a) the coupler head body or the knuckle pin, or (b) the knuckle,   the locking element engaging a depression or hole when the knuckle is in the uncoupled position, or   the locking element having a sloped surface by which it engages the hole or depression when the knuckle is in the uncoupled position.   
     
     
         15 . The coupler head of  claim 13 , wherein the resilient element is a leaf spring, wherein the locking element forms an integral part of the leaf spring. 
     
     
         16 . The coupler head of  claim 13 , wherein the resilient element comprises a compression spring arranged on a plunger, wherein the resilient element is configured to urge the locking element into the locking position. 
     
     
         17 . A method of retrofitting a coupler head of a coupler assembly of a multi-car rail vehicle with a safety device, wherein the coupler head comprises:
 a coupler head body, a knuckle configured for cooperating with a corresponding knuckle of another coupler head, and a knuckle pin having a knuckle pin axis, wherein the knuckle pin is mounted to the coupler head body and the knuckle is mounted to the knuckle pin so that the knuckle is rotatable about the knuckle pin axis relative to the coupler head body between a coupled position and an uncoupled position, and   a first lock which is configured to be moved, when the knuckle is in the coupled position, into a locking position in which it prevents rotation of the knuckle about the knuckle pin axis toward the uncoupled position,   the method comprising:
 providing the safety device in the form of a second lock, and 
 mounting the second lock on the coupler head in such a manner that, when the knuckle is in the uncoupled position, the second lock is able to:
 (a) prevent rotation of the knuckle about the knuckle pin axis toward the coupled position, and 
 (b) unlock, when a predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position, is exceeded, so that the second lock no longer hinders rotation of the knuckle about the knuckle pin axis toward the coupled position. 
 
   
     
     
         18 . The method of  claim 17 , further comprising at least one of:
 the safety device is mounted on the coupler head so as to keep the knuckle in a predetermined relative position with respect to the coupler head body when the knuckle is in the uncoupled position,   the second lock is arranged such that, when the knuckle is in the uncoupled position and the second lock is in a state in which it prevents rotation of the knuckle about the knuckle pin axis toward the coupled position, the second lock is visible from outside the coupler head,   the second lock is arranged such that, when the knuckle is in the uncoupled position and the second lock is in a state in which it prevents rotation of the knuckle about the knuckle pin axis toward the coupled position, the second lock is accessible and unlockable from outside the coupler head without a need to disassemble the coupler head,   the second lock is arranged on a top side of the coupler head, or   at least a part of the second lock is configured to deform when said predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position, is exceeded.   
     
     
         19 . A coupler assembly for a car of a multi-car rail vehicle, comprising:
 a coupler head, comprising:
 a coupler head body, a knuckle configured for cooperating with a corresponding knuckle of another coupler head, and a knuckle pin having a knuckle pin axis, wherein the knuckle pin is mounted to the coupler head body and the knuckle is mounted to the knuckle pin so that the knuckle is rotatable about the knuckle pin axis relative to the coupler head body between a coupled position and an uncoupled position, 
 a first lock which is configured to be moved, when the knuckle is in the coupled position, into a locking position in which it prevents rotation of the knuckle about the knuckle pin axis (A) toward the uncoupled position, and 
 a second lock which is configured to prevent, when the knuckle is in the uncoupled position, rotation of the knuckle about the knuckle pin axis toward the coupled position, wherein the second lock is further configured to unlock when a predetermined force, which acts on the knuckle so as to rotate the knuckle about the knuckle pin axis toward the coupled position, is exceeded, so that the second lock no longer hinders rotation of the knuckle about the knuckle pin axis toward the coupled position; and 
   energy absorption means configured to absorb energy when the coupler head collides with a corresponding coupler head of another car of the multi-car vehicle.