Truck mounted brake beam with removable brake heads

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.

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
 '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 '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.

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 40A, B and 40C, 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 40A, 40C to the bottom
 channeled elements 40B, 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 40A, C are
 shorter in length than the bottom channeled elements 40B, 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 40B, D.
 Referring to FIG. 6, the top channeled element 40A 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 44A1 and the wheel side
 vertical wall 44A2 are non-parallel and converge at the ends. The bottom
 channeled element 40B 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 44B1 (not shown) converges towards the unmodified wheel side
 vertical wall 44B2. Comparing this to the secondary beam 16, only the ends
 of the wheel side vertical wall 44C2 of the top channeled element 40C
 converges while the non-wheel side vertical wall 44C1 of the top channeled
 element 40C and both vertical walls of 44D1, D2 (not shown) of the bottom
 channeled element 40D 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 43A and 43B and the end of the actuating push rod 18 rides is
 secured to and rides between the bosses 43C and 43D. 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 43B and 44D 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 31A and 31B 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
 31C spaced below the bottom flange 31B sufficiently spaced such that it
 acts as a stop against the top surface 42B of the bottom channel 40B. The
 fastener 56 is a pin which extends through coaxial apertures in the
 flanges 31A, 31B and aperture 33. The length of the pin 56 is selected
 such that its head comes to rest on the top of top flange 31A without the
 bottom of the pin 56 engaging a top surface of flange 31C. The flanges 31A
 and 31B 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 31A. 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 31A 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.