Time switch mechanism

Claim 1

A time switch mechanism having switch means and a clock mechanism for automatically operating said switch means independently of the manual operation thereof, wherein the improvement comprises: a switch lever rotatable about a given axis between a start position and a terminal position and being spring-biased toward said terminal position; said switch means being positioned adjacent to said switch lever so that said switch means is actuated to one operating condition thereof by a first portion of said switch lever when the same is positioned at either of said start position and said terminal position, while said switch means is switched to the other operating condition when said switch lever is positioned at an intermediate position between said start position and said terminal position; a rotary switching cam manually rotatably mounted adjacent to said switch lever and having a first, a second and a third cam portion and a pin formed thereon, being spring-biased for rotation in a direction from an initial position at which said first cam portion faces against a second portion of said switch lever to a position in which said second portion faces against said second cam portion, then against said third cam portion and thereafter again against said first cam portion; click stop means cooperating with said pin of said switching cam for releasably holding said switching cam, respectively, at a first position at which said second cam portion faces against said second switch lever portion after said switch cam is rotated from said initial position, at a second position at which said third cam portion faces against said second lever portion and at a third position at which said first cam portion faces again against said second lever portion; a sector gear integrally secured to said switching cam so as to be rotatable therewith; a gear frictionally mounted on a rotatable shaft driven by said clock mechanism and engageable with said sector gear so as to drive said sector gear in the direction of rotation of said switching cam, the configuration of said sector gear being so determined that it is disengaged from said gear within the range of rotation of said switching cam before said switching cam is brought into said initial position thereof during its rotation; a time setting member having engaging means manually settable to a desired set time; and a timing cam driven by said clock mechanism, being coaxially disposed with said time setting member, and having engaging means, said timing cam cooperating with said time setting member so that said timing cam is shifted from a first position to a second position at said set time by the engagement of said engaging means thereof with said engaging means of said time setting member during rotation of said timing cam, said timing cam being so positioned with respect to a third portion of said switch lever that the same is held in said intermediate position to maintain said switch means in said other operating condition when said timing cam is in said first position and said switching cam is in said initial position, while, when said timing cam is in said second position and said switching cam is in said first position, said switch lever is held in said terminal position to maintain said switch means in said one operating condition, said second position of said switching cam at which said third cam portion faces against second portion of said switch lever being so determined that said switch lever is prevented from rotating from said intermediate position to said terminal position, to maintain said switch means in said other operating condition regardless of the operation of said timing cam, thereby determining a first manual set position of said time switch mechanism, and said third position of said switching cam at which said first cam portion again faces against said second portion of said switch lever is so determined that said switch lever is held in said start position so as to maintain said switch means in said one operating condition with said third portion of said switch lever being spaced from said timing cam, thereby determining a second manual set position of said time switch mechanism, and said initial position of said switching cam permitting automatic operation of said time switch mechanism.