Launcher for extendible and retractable bridge structure

Claim 2

In combination, a bridge launcher, a bridge structure articulated at one of its ends on a shaft located on the bridge launcher for movement between a retracted position wherein the bridge structure rests on the bridge launcher and an operative extended position wherein the bridge structure is adapted to bridge a span, a crossbeam articulated on the said shaft and having at least one arm extending away from said shaft, a positioning means including a positioning extendible element interconnecting a first point on the said arm which is spaced away from the shaft to a point on the bridge structure near the end thereof which is articulated on the shaft, said positioning extendible element forming a supporting brace for the bridge structure in the extended position thereof, and a drive means including at least one drive extendible element for operatively interconnecting the bridge launcher and second point on the said arm between the shaft and the said first point thereon, whereby said drive means is operable, when extended, to move the crossbeam and hence also the bridge structure via said positioning extendible element from said retracted position at least to a partially extended position.

Claim 3

The invention of claim 1, said crossbeam comprising a pair of parallel arms, one end of each arm being articulated on the shaft, and having a cross bar extending parallel to the shaft and interconnecting the pair of arms, said positioning means including a separate extendible element for each of said arms.

Claim 4

The invention of claim 2, said cross bar being spaced from and parallel to said shaft, said drive extendible element connected at one of its ends to said cross bar.

Claim 5

The invention of claim 1, said bridge launcher having a vertical end wall, said shaft axis being parallel to and located at the top of said end wall, said crossbeam arm being pivotable about said shaft axis from a position on top of the bridge launcher in the retracted position to a position against and supported by the said wall in the extended position.

Claim 6

The invention of claim 4, said positioning extendible element being adjustable while the crossbeam is supported against and bolted with the said end wall for adjusting the inclination of the extended bridge structure.

Claim 7

The invention of claim 4, said bridge launcher being an amphibious vehicle, and including a propeller recessable into said end wall when not in use.

Claim 8

The invention of claim 1, wherein said drive means is operable to drive said bridge structure from the retracted position at least to a partially extended position at which the center of gravity of the bridge structure has at least reached a point above the said shaft.

Claim 9

In combination, a bridge launcher, a bridge structure articulated at one of its ends on a shaft located on the bridge launcher for movement between a retracted position wherein the bridge structure rests on the bridge launcher and an operative extended position wherein the bridge structure is adapted to bridge a span, a crossbeam articulated on the said shaft and having at least one arm extending away from said shaft, a positioning means including a positioning extendible element interconnecting a first point on the said arm which is spaced away from the shaft to a point on the bridge structure near the end thereof which is articulated on the shaft, said positioning extendible element forming a supporting brace for the bridgE structure in the extended position thereof, and a drive means including at least one drive extendible element, said drive extendible element comprising an intermediate member pivotally connected to said shaft for movement in a plane perpendicular to said shaft, two other points on the intermediate member being pivotally connected to first and second extendible members, one of which is connected at its other end to the bridge launcher and the other of which is connected at its other end to the bridge structure near the shaft, the three said pivotal connections of the intermediate member forming an isosceles triangle with the pivot connection to the shaft being the apex thereof, whereby retracting both of said first and second extendible elements lifts the bridge structure off of the bridge launcher.

Claim 10

In combination, a bridge launcher, a bridge structure articulated at one of its ends on a shaft located on the bridge launcher for movement between a retracted position wherein the bridge structure rests on the bridge launcher and an operative extended position wherein the bridge structure is adapted to bridge a span, a crossbeam articulated on the said shaft and having at least one arm extending away from said shaft, a positioning means including a positioning extendible element interconnecting a first point on the said arm which is spaced away from the shaft to a point on the bridge structure near the end thereof which is articulated on the shaft, said positioning extendible element forming a supporting brace for the bridgE structure in the extended position thereof, and a drive means including at least one drive extendible element, said drive extendible element comprising an intermediate member pivotally connected to said shaft for movement in a plane perpendicular to said shaft, two other points on the intermediate member being pivotally connected to first and second extendible members, one of which is connected at its other end to the bridge launcher and the other of which is connected at its other end to the bridge structure near the shaft, the three said pivotal connections of the intermediate member forming an isosceles triangle with the pivot connection to the shaft being the apex thereof, whereby retracting both of said first and second extendible elements lifts the bridge structure off of the bridge launcher.

Claim 11

The invention of claim 8, said crossbeam comprising a pair of parallel arms, one end of each arm being articulated on the shaft, and having a cross bar extending parallel to the shaft and interconnecting the pair of arms, said positioning means including a separate extendible element for each of said arms.

Claim 12

The invention of claim 8, said bridge launcher having a vertical end wall, said shaft axis being parallel to and located at the top of said end wall, said crossbeam arm being pivotable about said shaft axis from a position on top of the bridge launcher in the retracted position to a position against and supported by the said wall in the extended position.

Claim 13

The invention of claim 10, said positioning extendible element being adjustable while the crossbeam is supported against and bolted with the said end wall for adjusting the inclination of the extended bridge structure.

Claim 14

The invention of claim 8, wherein said drive means is operable to drive said bridge structure from the retracted position at least to a partially extended position at which the center of gravity of the bridge structure has at least reached a point above the said shaft.

Claim 15

In combination, a bridge launcher, a bridge structure articulated at one of its ends on a shaft located on the bridge launcher for movement between a retracted position wherein the bridge structure rests on the bridge launcher and an operative extended position wherein the bridge structure is adapted to bridge a span, a crossbeam articulated on the said shaft and having at least one arm extending away from said shaft, a positioning means including a positioning extendible element interconnecting a first point on the said arm which is spaced away from the shaft to a point on the bridge structure near the end thereof which is articulated on the shaft, said positioning extendible element forming a supporting brace for the bridge structure in the extended position thereof, and a drive means including at least one drive extendible element connected at one end to the bridge launcher, for raising both the bridge and the crossbeam from said retracted position to at least a partially extended position at which the center of gravity of the bridge and crossbeam are generally above the said shaft, and said positioning extendible element is in a position at which a further extension thereof will carry the said center of gravity onto the side of a vertical plane through the shaft axis away from the launcher and toward the extended position.

Claim 16

In combination, a bridge launcher, a bridge structure articulated at one of its ends on a shaft located on the bridge launcher for movement between a retracted position wherein the bridge structure rests on the bridge launcher and an operative extended position wherein the bridge structure is adapted to bridge a span, a crossbeam articulated on the said shaft and having at least one arm extending away from said shaft, a positioning means including a positioning extendible element interconnecting a first point on the said arm which is spaced away from the shaft to a point on the bridge structure near the end thereof which is articulated on the shaft, said positioning extendible element forming a supporting brace for the bridge structure in the extended position thereof, and a drive means including at least one drive extendible element connected at one end to the bridge launcher, for raising both the bridge and the crossbeam from said retracted position to at least a partially extended position at which the center of gravity of the bridge and crossbeam are generally above the said shaft, and said positioning extendible element is in a position at which a further extension thereof will carry the said center of gravity onto the side of a vertical plane through the shaft axis away from the launcher and toward the extended position.

Claim 17

The invention of claim 13, said drive extendible element connected at its other end to a second point on the said arm between the shaft and the said first point thereon, whereby said drive means is operable, when extended, to move the crossbeam and hence also the bridge structure via said positioning extendible element from said retracted position to at least a partially extended position.

Claim 18

The invention of claim 13, said drive extendible element comprising an intermediate member pivotally connected to said shaft for movement in a plane perpendicular to said shaft, two other points on the intermediate member being pivotally connected to first and second extendible members, one of whicH is connected at its other end to the bridge launcher and the other of which is connected at its other end to the bridge structure near the shaft, the three said pivotal connections of the intermediate member forming an isosceles triangle with the pivot connection to the shaft being the apex thereof, whereby retracting both of said first and second extendible elements lifts the bridge structure off of the bridge launcher.

Claim 19

The invention of claim 13, said bridge launcher having a vertical end wall, said shaft axis being parallel to and located at the top of said end wall, said crossbeam arm being pivotable about said shaft axis from a position on top of the bridge launcher in the retracted position to a position against and supported by the said wall in the extended position.

Claim 20

The invention of claim 16, said positioning extendible element being adjustable while the crossbeam is supported against and bolted with the said end wall for adjusting the inclination of the extended bridge structure.