Abstract:
A truck mounted rail brake including at least a primary beam having a center section and a pair of end sections with guide end extensions. A brake head is removably mounted to the end sections by a pin. The pin is dimensioned to allow pivotal movement of the brake head about the pin. The pin is retained in the brake head by either a tab or another pin above and transverse to the first pin.

Description:
CROSS REFERENCE 
     This is a continuation-in-part of U.S. application No. 09/046,847, filed Mar. 13, 1998, which is a continuation-in-part of U.S. application Ser. No. 08/874,228, filed Jun. 13, 1997, now U.S. Pat. No. 5,947,236. 
    
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
     The present invention relates generally to brake designs for rail cars, and more specifically to truck mounted brake systems. 
     Truck mounted brakes throughout the railroad industry include either a double actuator system as illustrated in U.S. Pat. No. 3,499,507 or a single actuator system as illustrated in U.S. Pat. Nos. 5,400,874 and 5,495,921. In all three of these systems, the actuator rods extend through holes in the bolster of the truck. The primary and secondary beams are unitary cast iron beams. The beams are U-shaped having a vertical base and two horizontal walls extending therefrom. The actuator or actuators are mounted to the vertical base and the actuator rods are mounted and extend through openings also in the vertical base. The brake heads are cast integral at each end of the beam. 
     Another example of a truck mounted brake having a single actuator is illustrated in U.S. Pat. Nos. 4,766,980 and 4,653,812. By moving the actuator rods outside of the center section, they pass under the bolster of the truck and no holes through the bolsters are required. The brake beams are shown as having a rolled steel center channel section with removable end sections having cast brake shoe heads and projecting guide end extensions bolted to the center section. The load on the beam is carried by the bolts which join the end sections to the center section. As with the previous unitary beams, the channeled portion is generally U-shaped having a vertical base wall with two opposed horizontal walls extending therefrom. 
     A unitary brake head and projecting guide end extensions secured to a bow type beam by fasteners is illustrated in U.S. Pat. Nos. 5,810,124 and 5,069,312. Again, the fasteners are load bearing and as described in the &#39;124 Patent, rivets are used. Separate brake shoe heads and guide end extensions being secured by a common fastener is illustrated in U.S. Pat. No. 2,491,086. As in the &#39;124 Patent, from the same assignee, rivets are used since they are a load bearing connection. Removable brake heads are also shown in U.S. Pat. Nos. 4,771,868 and 5,806,634. 
     There is a continuous drive to reduce the cost, size and weight of the truck mounted brake. 
     The present invention is a truck mounted rail brake including at least a primary beam having a center section and a pair of end sections with guide end extensions to be received in the slots of the truck. The center portion may include two opposed channel elements joined to each other and each having a horizontal base and two vertical walls. A brake actuator is connected to the primary beam and a brake head is removably joined to each end section of the beam. Preferably, the brake head is joined to the end section by a pin. In one embodiment, a tab is provided on the head and a portion of the tab is bent over the pin to retain it in the brake head and the end section. In a second embodiment, a second pin is removably joined to the brake head and extends above the first pin along an axis transverse to and intersecting an axis of the first pin to retain the first pin in the brake head and the end section. The first pin is dimensioned to allow the brake head to pivot about the first pin whose axis is transverse to the longitudinal axis of the beam. 
     With respect to the beam, the vertical walls of the opposed channeled elements may extend either from the base towards each other or away from each other. The channel elements are joined by a first weldment. The first weldments are hollow and the bases include openings to the hollow of the first weldments. The cross-section of the end portions of at least one of the channeled elements are smaller than the cross-section of a center portion of the at least one channeled element. 
     A second brake beam may be included also having a center section with a pair of end sections including guide end extensions. The second beam also includes at least one channel member having a horizontal base and two vertical walls. 
     Another truck mounted rail brake would include at least a primary beam including a center section, and at each end, an end section having a guide end extension to be received in the slots in a truck. A brake head has a slot in the back which receives the end sections and which allows removal of the brake head transverse the longitudinal axis of the beam. A first pin extends through the aligned aperture in a wall of the slot and in the end section and removably maintains the brake head on the end section. In one embodiment, a tab is provided on the brake head and a portion of the tab is bent over the pin to retain the pin in the brake head and the end section. In a second embodiment, an opening is provided in the brake head above the slot and has an axis transverse to and intersecting coaxial axis of the aligned apertures. A second pin extends through the opening above the first pin to retain the first pin in the apertures. 
     The brake beam further includes two transverse walls, one on each side of the brake head to limit the movement of the brake head along the longitudinal axis. The slot, first pin and separation of the transverse wall is already dimensioned to allow the brake head to pivot about the pin. The slot is formed by two flanges extending from the back of the brake head and vertically spaced sufficiently to receive the end section of the beam. A portion of the center section of the beam extends laterally below a portion of the end section. A third flange extends from the back of the beam and is vertically spaced from the other two flanges sufficiently to engage a portion of the center section of the beam below the end section as a stop. 
     Another truck mounted brake includes at least a primary beam including along a longitudinal axis, a center section and at each end, an end section having an end extension to be received in a slot in a truck. A brake head is removably mounted to the end extension by a first pin which is dimensioned to allow the head to pivot about the pin, whose axis is transverse to the longitudinal axis of the beam. As in the previous embodiments, the first pin is retained either by a tab on the brake head or a second pin which extends above the first pin along an axis transverse to and intersecting the axis of the first pin. 
     Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 a perspective view of a truck mounted brake mounted the truck incorporating the principles of the present invention. 
     FIG. 2 is an exploded view of the truck mounted brake of FIG. 1 incorporating the principles of the present invention. 
     FIG. 3 is a cross section taken along lines III—III of FIG. 1 of the primary beam. 
     FIG. 4 is a cross section taken along lines IV—IV of FIG. 1 of the secondary brake beam. 
     FIG. 5 is a perspective view of another embodiment of a truck mounted brake mounted to the truck incorporating the principles of the present invention. 
     FIG. 6 is an exploded view of the truck mounted brake of FIG.  5 . 
     FIG. 7 is a cross sectional view taken along lines VII—VII of FIG. 8 of a brake head on a brake beam according to the principles of the present invention. 
     FIG. 8 is a cross sectional view of the brake head taking along lines VIII—VIII of FIG. 7 without the brake beam. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     A truck mounted brake is shown in FIG. 1 with respect to bolster  10  of the truck and a wheel  12 . The illustration is for a double axle truck and therefore will be described with respect to two brake beams. 
     The truck mounted brake illustrated in FIGS. 1 and 2 include a primary brake beam  14  and a secondary brake beam  16  on opposite sides of the bolster  12  and interconnected by force transmission or push rod assembly  18 . An actuator  20  is supported by the primary beam  14  and is connected to the secondary beam  16  by the push rods  18 . A hand brake cable  22  is connected to the actuator  20  and to cable reaction bracket  24 , equalization plate  26  and chain  28 . 
     At each end of the primary beam  14  and the secondary beam  16 , is a brake head  30  having brake shoes  32  secured thereto by removable shoe key  34 . Also, extending from the ends of each of the brake beams are guide end extensions  36  which are received in slots in the side frames of the truck. Each of the brake heads  30  and brake shoes  32  are adjacent to respective wheel  12 , only one of which is illustrated. 
     The system so far described is well known in the industry and is illustrated for example, in U.S. Pat. Nos. 4,766,980 and 4,653,812. The operation of the actuator  20 , with or without slack adjusters, and the push rod assemblies  18  to operate the pair of brake beams  14  and  16  is well known and will not be described here in detail. 
     A first embodiment of the improved brake beam system of the present invention is illustrated in detail in FIGS.  2 - 4 . The primary beam  14  and the secondary beam  16  each include a center section having one or more channeled elements  40  each including a horizontal base  42  and pair of vertical side walls  44 . While the secondary beam  16  includes only one channel member  40 , the primary beam  14  includes a pair of opposed channel members  40 . In both beams, the base  42  is horizontal and the side walls  44  are vertical. This increases the stiffness of the center of the beams to braking forces transverse to the side walls  44  and within the plane of the base  42 . This is to be distinguished from the U-shaped beams of the prior art wherein the corresponding base wall  42  is vertical and the corresponding side walls  44  are horizontal. 
     The specific orientation and design of the present center sections  40  allows them to be standard U or C channeled stock of substantially reduced weight and cost compared to that of the prior art brake beams. The channeled stock has a large radius of curvature or thickened intersection of the vertical walls  44  to the base  42  which increases the rigidity. Also, box channel or rectangular cross-section stock may be used. Another advantage of using stock channels for the center section of the beam is easy of modification for different gauge tracks. No redesign or special forging is needed. 
     The primary brake beam  14  includes a pair of end section  50  having a tongue portion  52  slidably received within the channel of the center section  40 . An opening  54  is provided in the end section  50  for the force transmission mechanism or the push rods  18 . Fasteners  56  extend through aligned apertures in the base wall  42  of the center section and the tongue  52  of the end section and into nuts  58  to secure the end sections in their extended position relative to the center section  40 . Fasteners  56  secure or lock the end sections in their extended position and secure the pair of center sections  40  to each other. 
     The secondary beam  16  also includes a pair of end sections  60  having a tongue  62  received within the channel of the center section  40 . A pair of fasteners  66  extend through the horizontal wall  42  of the center section  40  and through aligned apertures in the tongue  62  of the end section  60  and into nuts  68  to secure the end sections in their extended position relative to the center section  40 . 
     The actuator  20  is supported by the primary brake beam  16  through bell crank lever  70 . Opposite ends of the actuator  20  are secured by pins  80  received through aperture  72  in the bell crank  70 . A cotter pin  82  connected through the end of the pin  80 . The bell crank  70  is pivotally connected to the end section  50  in opening  54  of the first beam by a pin  84  received in aperture  74 . A cotter pin  88  is provided at the end of pin  84  to secure it in place. One end of the push rod assembly  18  is secured to the bell crank  70  by a pin  90  received in aperture  76  of the bell crank  70 . A bushing  92  is provided in aperture  76  of the lever  70  and a cotter pin  94  holds the pin  90  in place. The other end of the push rod  18  is received in opening  64  of the end section  60  of the second beam  16  and is secured therein by pin  96  and cotter pin  98 . 
     Another embodiment of the brake beam incorporating the principles of the present invention is illustrated in FIGS. 5 and 6. Those elements which have the same general structure and function as that as in FIGS.  1 - 4  have the same numbers. Those having modified or new part elements have odd numbers. The purpose of the embodiment of FIGS.  5 - 8  as distinguished from that of FIGS.  1 - 4  is that in FIGS. 5 and 6, actuator  20  and push rods  18  stay with the beams and are not removed with the brake heads  30  from the truck. In FIGS.  1 - 4 , the actuator  20  and the connecting rods  18  are removed with the brake heads  30  from the truck. 
     The primary beam  14  and the secondary beam  16  each include a center section having two opposed channeled elements  40 A, B and  40 C, D respectively. Each includes a horizontal base  42  and pair of vertical side walls  44 . In both beams, the base  42  is horizontal and the side walls  44  are vertical. The specific orientation and design of the present center sections  40  allows them to be standard U or C channeled stock of substantially reduced weight compared to that of the prior art brake beams. Also, box channel or rectangular cross-section stock may be used. 
     The channeled elements  40  of the primary and secondary brake beams have their opposed bases  42  adjacent with their vertical walls  44  extending away from each other. In the embodiment of FIGS.  1 - 4 , the vertical walls  40  extend towards each other from their opposed bases  42 . A pair of first weldments  51  secure the top channeled element  40 A,  40 C to the bottom channeled elements  40 B, D. Preferably, the weldments  51  are tubes. Openings  41  in the base provide access to the hollowed weldments  51  and allows debris and water to run off through the beams. The openings  41  may be smaller than the weldments  51 . The top channeled elements  40 A, C are shorter in length than the bottom channeled elements  40 B, D and are secured to each other at their ends by a second weldment illustrated as a plate  53 . The guide end extensions  36  are secured to the center channeled elements  40  by the weldment  53  and a third weldment  55  connected to the bottom channeled element  40 B, D. 
     Referring to FIG. 6, the top channeled element  40 A of the primary beam  14  has a smaller cross-section at the ends compared to the cross-section at its center. Both the non-wheel side vertical wall  44 A 1  and the wheel side vertical wall  44 A 2  are non-parallel and converge at the ends. The bottom channeled element  40 B of the primary beam  14  also has a smaller cross section at its ends than it does at the center. Only the non-wheel side vertical wall  44 B 1  (not shown) converges towards the unmodified wheel side vertical wall  44 B 2 . Comparing this to the secondary beam  16 , only the ends of the wheel side vertical wall  44 C 2  of the top channeled element  40 C converges while the non-wheel side vertical wall  44 C 1  of the top channeled element  40 C and both vertical walls of  44 D 1 , D 2  (not shown) of the bottom channeled element  40 D remain parallel to the center section. 
     The actuator  20  is supported by the primary brake beam  14  through bell crank levers  70 . Opposite ends of the actuator  20  are secured by pins  80  received through aperture  72  in the bell cranks  70 . A cotter pin  82  connected through the end of the pin  80 . The bell crank  70  is pivotally connected to the center section  40  of the first beam by a pin  84  received in aperture  74  in the bell crank  70  and bores  45  in bases  42 . A cotter pin  88  is provided at the end of pin  84  to secure it in place. One end of the push rod assembly  18  is secured to the bell crank  70  by a pin  90  received in aperture  76  of the bell crank  70 . A cotter pin  94  holds the pin  90  in place. The other end of the push rod  18  is received and secured to the center section of channeled element  40  of the second beam  16  by pin  96  and cotter pin  98  through bore  45  in base  42 . 
     Bosses  43  are provided on the base  42  and include the bores  45  which receive the pins  90  and  96 . Bell crank  70  is secured and rides between the bosses  43 A and  43 B and the end of the actuating push rod  18  rides is secured to and rides between the bosses  43 C and  43 D. For sake of clarity, the bosses  43  have been deleted and are shown in FIGS. 5 and 6. All of the bosses  43  act as spacers for the actuator and push rod assembly. The bottom bosses  43 B and  44 D also act as wear plates since they support the bell crank  70  and the end of the push rod  18  respectfully. The bosses  43  are mounted or secured to the bases  42  by welding. Obviously, this welding takes place prior to the joining of the channeled elements together. 
     Since the guide end extensions  36  are unitary with the beam structure, the brake head  30  with the brake shoe  32  are removable from the guide end extensions  36  and the beam. The brake head  30  includes a pair of spaced blocks  31  on its back wall between which is received a portion of the guide end extension. A pin  56  is extended through aligned apertures  33  in the blocks  31  and the guide end extension  36 . A tab  35  extending from the top block  31  is bent over the top of the pin  56  to secure it in place. The pin  56  in combination with spacing between the blocks  31  and the guide end extension  36  allows for about 3 degrees of movement about a horizontal axis. Since the load is carried by the beam instead of the pin  56 , the mounting need not be fixedly secured. Also, the tab  35  being an integral part of the brake head  30  prevents the pin  56  from being lost. 
     The brake head  30  is restricted from significant lateral movement by the weldment  53  and a transverse wall of the guide foot  36 . This would also minimize rotation or swivelling of the brake head  30  laterally. 
     To replace the brake head, the shoes  32  must be removed and beams are moved away from the wheel. The tab  35  is straightened and the pin  56  removed. The brake head  30  is then moved towards the wheel until it clears the guide end extension  36  and then is moved parallel to the brake beam. The relationship of the brake head  30  and the blocks  31  to the guide end extension  36  and the weldment  53  transfers the forces on the brake head  30  to the brake beam and is not primarily dependent upon a pin  56 . 
     Another embodiment of the brake head is illustrated in FIGS. 7 and 8. This is a cast brake head. The numbers used in FIGS. 5 and 6 having the same function are used in FIGS. 7 and 8. A portion of the beam  14  is illustrated in FIG. 7 but has been deleted from FIG. 8 for clarity. The brake head  30  includes a first pair of flanges  31 A and  31 B which are spaced sufficiently to receive the guide end extension  36  which is the end portion of the beam. Also provided on the brake head  30  is a third flange  31 C spaced below the bottom flange  31 B sufficiently spaced such that it acts as a stop against the top surface  42 B of the bottom channel  40 B. The fastener  56  is a pin which extends through coaxial apertures in the flanges  31 A,  31 B and aperture  33 . The length of the pin  56  is selected such that its head comes to rest on the top of top flange  31 A without the bottom of the pin  56  engaging a top surface of flange  31 C. The flanges  31 A and  31 B form a machined slot in the back of the head  30 . 
     To retain the pin  56  in apertures  33 , a pair of side walls  37  are provided extending up from the flange  31 A. A pin  38  extends through openings in the side walls  37  and are secured thereto by a cotter pin  39 . The axis of the pin  38  is above and transverse to and intersects the axis of the pin  56  and the apertures  33 . The pin  38  prevents loosely fitting pin  56  from exiting the apertures  33  and thereby maintains in the flanges  31 A and B and the end extension  36 . Although a pair of side walls are shown as the preferred embodiment, the pin could be removably secured and extend from a single side wall or other structure of the brake head  30 . Also, a simple cotter pin with bend ends can be used instead of the pin  38  through the openings in the side walls  37  as an alternative. 
     Although the removable brake heads  30  of FIGS.  5 - 8  are shown with the beam structure of FIGS. 5 and 6, the brake head can also be made to be used with the beam structure of FIGS.  1 - 4  as long as it is not integral to the end extension  36 . The securement of the end extension  36  to the beam must be independent of the mounting of the brake head  30  to the beam. Otherwise, the connection would be load bearing and the head of FIGS.  4 - 8  cannot be used. 
     Although the present invention has been described and illustrated in detail, it is to be clearly understood that the same is by way of illustration and example only, and is not to be taken by way of limitation. The spirit and scope of the present invention are to be limited only by the terms of the appended claims.