Retractable step

Claim 2

A retractable step, comprising; a step supporting member, a step member, pivotal linkage connecting said step member to said supporting member for movement between a first position raised and retracted up under said supporting member and a second position lowered and extended in front of said supporting member, operative means provided on said supporting member and connected to said pivotal linkage for raising and retracting said step member into said first position, biasing means connected to said operative means and acting to dispose and hold said step member in said second position, said operative means including an overcenter linkage set by said biasing means for locking said step member in said second position for safe use, power operated means connected to said operative means and having overriding opposition to said biasing means for unlocking said step member and allowing the raising and retraction thereof, said power operating means including a diaphragm operated mechanism having one side thereof connected to a vacuum pressure source and the other side to said operative means, and including door operated switch means interposed between said vacuum pressure source and said operative means for venting the system and inactivating said power operated means.

Claim 3

A retractable step and associated operating mechanism, comprising; a step supporting member suitable for being mounted under a doorway provided within a recreational vehicle, a step member of suitable width and depth for supporting the weight of persons making use thereof and having rearwardly extending side rails on each side thereof for free hanging connection to said supporting member, pivotal links providing free hanging connection between the side rails and said supporting member and for assuring relatively horizontal translaterial movement of said step member between a first position raised and retracted up under said supporting member and a second position lowered and extended in front of said supporting member, operative means provided on said supporting member and extending therebeneath for raising and retracting said step member into said second position, said operative means including an axially rotatable member having relatively spaced and circumferentially offset lever arm connections provided thereon and a vacuum pressure responsive diaphragm operated member connected to one of said lever arm connections, a pivotal link connected between another of said lever arm connections and said free hanging pivotal links for retracting actuation of said step member, and spring means connected between still another of said lever arm connections and said supporting member for biasing said step member through said axially rotatable member into said second position and for also biasing said first mentioned other lever arm connection into an overcenter lock-up position precluding inadvertant retraction of said step member.

Claim 4

A retractable step and associated operating mechanism, comprising; a step supporting member suitable for being mounted under a doorway provided within a recreational vehicle, a step member of suitable width and depth for supporting the weight of persons making use thereof and having rearwardly extending side rails on each side thereof for free hanging connection to said supporting member, pivotal links providing free hanging connection between the side rails and said supporting member and for assuring relatively horizontal translaterial movement of said step member between a first position raised and retracted up under said supporting member and a second position lowered and extended in front of said supporting member, operative means provided on said supporting member and extending therebeneath for raising and retracting said step member into said second position, said operative means including an axially rotatable member having relatively spaced and circumferentially offset lever arm connections provided thereon and a vacuum pressure responsive diaphragm operated member connected to one of said lever arm connections, a pivotal link connected between another of said lever arm connections and said free hanging pivotal links for retracting actuation of said step member, and spring means connected between still another of said lever arm connections and said supporting member for biasing said step member through said axially rotatable member into said second position and for also biasing said first mentioned other lever arm connection into an overcenter lock-up position precluding inadvertant retraction of said step member.

Claim 5

The retractable step and associated operating mechanism of claim 2, including: door operated means for venting the vacuum system that raises and retracts said step member to insure the overcenter biased extension of said step member under said doorway when the door closure thereof is open.