Light assembly raising and lowering mechanism with pin and dog device

Claim 2

Raising and lowering mechanism for a light assembly in a high mast lighting structure which comprises a hollow pole having a base section, a top section, and a capping housing mounted on said top section, a light assembly supporting ring encircling said pole and having a fixed operating position adjacent said housing, means for imparting travelling movement to said ring along said pole comprising a winch in said base section, flexible line means extending through said pole and housing and having a pair of opposed branches connecting said winch and ring, and means for locating and supporting said ring in said fixed position comprising two pairs of opposed dogs pivotally mounted in said housing, and a pair of pins fixedly mounted on said ring, each said pin having a pair of opposed shoulders engageable by one of said pairs of dogs to define said fixed position.

Claim 3

Raising and lowering mechanism for a light assembly in a high mast lighting structure as defined in claim 1, each said dog having an over center position with respect to its pivotal axis, a shoulder engageable with one of said pin shoulders to define said fixed position, an inclined surface contiguous with said dog shoulder, and a projection extending laterally of said pivotal axis thereof, each said pair of dogs having a first path of movement wherein said dogs fall towards each other and a second path of movement wherein said dogs fall away from each other, each said pin during upward travel thereof having leading surfaces engageable with said inclined dog surfaces to separate said dogs within said first path of movement and permit subsequent engagement of said pin shoulders with said dog shoulders, each said pin also having surfaces engageable with said projections to move said dogs into said second path of movement, said pin shoulders during downward travel of said pin being engageable with said projections to return said dogs into said first path of movement.

Claim 4

Raising and lowering mechanism for a light assembly in a high mast lighting structure as defined in claim 1, including a housing member surrounding each said pair of dogs, each said housing member having an opening for reception of said pin, and a plate fixed to said ring and on which said pin is mounted, said plate being arranged to close said opening following disposition of said pin in said housing member.

Claim 5

Raising and lowering mechanism for a light assembly in a high mast lighting structure as defined in claim 1, said flexible line means comprising a first line connected to said winch, a pulley block connected to said first line, a pulley in said block, a second line extending around said pulley and comprising said pair of branch lines, and a pair of guide pulleys for each said branch line mounted in said housing, said branch lines being connected to said ring at diametrically opposed locations thereon.