Portable extendable signal light platform

Claim 2

A warning device for carriage on the roof of an emergency vehicle, comprising a platform having emergency signal equipment mounted thereon, a cabinet fixedly supported on the roof of said vehicle, elevating means in said cabinet for moving said platform between a retracted and an extended position, said platform in its retracted position resting on and providing a cover for the cabinet and its extended position being disposed above said cabinet in spaced relation thereto.

Claim 3

The invention as set forth in claim 1 in which said elevating means comprises a lazy-tong structure having its lower ends slidably mounted within the cabinet, and its upper ends slidably mounted on said platform, and means for moving the lower ends of said lazy-tong structure toward and away from each other to raise and lower said platform.

Claim 4

An extendable platform apparatus, comprising a cabinet, a platform, guide means on said cabinet and platform, a first set of crossed links pivotally interconnected intermediate their lengths and having their lower ends slidably interconnected to said guide means on said cabinet, a second set of crossed links pivotally interconnected intermediate their lengths and having their lower ends pivotally connected to the upper ends of said first set of links and their upper ends slidably interconnected to said guide means on said platform, a reversible drive motor, a rotatable shaft operatively interconnected to said motor for rotation thereby, and means operatively interconnected to the lower ends of said first set of links and to said shaft whereby rotation of said shaft in one direction will draw the lower ends of said first set of links toward each other for raising said platform with respect to said cabinet and rotation of said shaft in an opposite direction will move said lower ends of said first set of links away from each other to lower said platform with respect to said cabinet.

Claim 5

An extendable platform apparatus, comprising a cabinet, a platform, guide means on said cabinet and platform, a first set of crossed links pivotally interconnected intermediate their lengths and having their lower ends slidably interconnected to said guide means on said cabinet, a second set of crossed links pivotally interconnected intermediate their lengths and having their lower ends pivotally connected to the upper ends of said first set of links and their upper ends slidably interconnected to said guide means on said platform, a reversible drive motor, a rotatable shaft operatively interconnected to said motor for rotation thereby, and means operatively interconnected to the lower ends of said first set of links and to said shaft whereby rotation of said shaft in one direction will draw the lower ends of said first set of links toward each other for raising said platform with respect to said cabinet and rotation of said shaft in an opposite direction will move said lower ends of said first set of links away from each other to lower said platform with respect to said cabinet.

Claim 6

The invention as set forth in claim 3 in which the lower ends of said first and second sets of links are curved downwardly.

Claim 7

The invention as set forth in claim 3 with the addition that a pair of braces are pivotally connected to said second set of links and platform for retaining said platform centered with respect to the upper ends of said second set of links.

Claim 8

The invention as set forth in claim 3 in which the ends of said shaft are oppositely threaded, and said means being operatively interconnected to the lower ends of said first set of links comprises a pair of follower blocks, said blocks having threaded openings therein for the reception of the threaded ends of said shaft.

Claim 9

The invention as set forth in claim 3 with the addition that a pair of limit switches connected to said motor are mounted on said cabinet, one of said switches being engageable with said platform as the lower ends of said first set of links are moved away from each other and the other one of said switches being engageable with means at the lower ends of said first set of links as said lower ends are moved toward each other.

Claim 10

The inventioN as set forth in claim 3 in which each set of links comprises two pairs of laterally spaced crossed links, a first pair of plates interconnecting the lower ends of the pairs of links in said first set of links, a second pair of plates interconnecting the upper ends of the pairs of links in said second set of links, a slide pivotally mounted on the lower end of each link in said first set and slidably received in the guide means on the cabinet, and a slide pivotally mounted on the upper end of each link in said second set and slidably received in the guide means on said platform.

Claim 11

An extendable platform apparatus, comprising a cabinet, a platform, a first pair of guides in said cabinet, a second set of guides on said platform a first set of links comprising two pairs of crossed links, a first pair of plates interconnecting the lower ends of each pair of links, slides pivotally mounted on the lower ends of the links in said first set and slidably carried in said first set of guides a second set of links comprising two pairs of crossed links pivotally connected at their lower ends to said first set of links, a second pair of plates interconnecting the upper ends of each pair of links in said second set, slides pivotally mounted on the upper ends of the links in said second set and slidably carried in said second set of guides, a threaded follower block mounted on each of said first pair of plates, a rotatable shaft supported in said first pair of plates, a rotatable shaft supported in said cabinet and having oppositely threaded ends received in said follower blocks whereby rotation of said shaft in one direction will cause said first and second set of links to move said platform outwardly from said cabinet and rotation of said shaft in an opposite direction will cause said links to move said platform toward said cabinet, reversible drive means for rotating said shaft, and a pair of braces pivotally connected to said platform and second set of links.

Claim 12

An extendable platform apparatus, comprising a cabinet, a platform, a first pair of guides in said cabinet, a second set of guides on said platform a first set of links comprising two pairs of crossed links, a first pair of plates interconnecting the lower ends of each pair of links, slides pivotally mounted on the lower ends of the links in said first set and slidably carried in said first set of guides a second set of links comprising two pairs of crossed links pivotally connected at their lower ends to said first set of links, a second pair of plates interconnecting the upper ends of each pair of links in said second set, slides pivotally mounted on the upper ends of the links in said second set and slidably carried in said second set of guides, a threaded follower block mounted on each of said first pair of plates, a rotatable shaft supported in said first pair of plates, a rotatable shaft supported in said cabinet and having oppositely threaded ends received in said follower blocks whereby rotation of said shaft in one direction will cause said first and second set of links to move said platform outwardly from said cabinet and rotation of said shaft in an opposite direction will cause said links to move said platform toward said cabinet, reversible drive means for rotating said shaft, and a pair of braces pivotally connected to said platform and second set of links.

Claim 13

The invention as set forth in claim 9 with the addition that a pair of limit switches are connected to said drive means, one of said switches being engageable with said platform as it is moved toward said cabinet to deenergize said drive means and the other of said switches being engageable with means on one of said first pair of plates to deenergize said drive means as said platform is moved outwardly from said cabinet.

Claim 14

A warning device, comprising a platform having emergency signal equipment mounted thereon, a cabinet having an open upper end, a plurality of pairs of crossed links with the links in each pair being pivotally joined together intermediate their lengths and each pair of said links being pivotally joined at their ends to the next adjacent pair of links, the lower end of each of said links being curved downwardly with respect to the upper end thereof, the upper ends of the uppermost pair of said links being slidably interconnected to said platform and the lower ends of the lowermost pair of said links being slidably interconnected to said cabinet, means in said cabinet for moving the lower ends of said lowermost pair of links toward and away from each other to cause said plurality of links to raise and lower said platform, said platform in lowered position resting on and providing a cover for said cabinet.

Claim 15

A warning device, comprising a platform having emergency signal equipment mounted thereon, a cabinet having an open upper end, a plurality of pairs of crossed links with the links in each pair being pivotally joined together intermediate their lengths and each pair of said links being pivotally joined at their ends to the next adjacent pair of links, the lower end of each of said links being curved downwardly with respect to the upper end thereof, the upper ends of the uppermost pair of said links being slidably interconnected to said platform and the lower ends of the lowermost pair of said links being slidably interconnected to said cabinet, means in said cabinet for moving the lower ends of said lowermost pair of links toward and away from each other to cause said plurality of links to raise and lower said platform, said platform in lowered position resting on and providing a cover for said cabinet.

Claim 16

A warning device as set forth in claim 11 with the addition that said platform and cabinet have guide means for guiding the movements of the link ends slidably interconnected thereto.