US 6,727,440 B1Granted

Electromechanical program timer with delay sections

AssigneeNorm Pacific Automation Corp.

InventorsWe-Chieh Wen, Shih-Chi Chan

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Abstract

An electromechanical program timer provides at least a section with a slower timing speed besides a major timing speed. The timer includes a driving motor rotationally drives a driving shaft. A driving gear and an eccentric shaft are formed on the driving shaft for driving a cam disk through a main driven gear and via a pushing pawl to a driven ratchet respectively. The main driven gear includes at least a missing gear portion where the driving gear is free from driving the main driven gear, and the pushing pawl and the driven ratchet take place. The driving shaft engages and rotates the cam disk through the main driven gear in a major timing speed. While at the missing gear portion, the eccentric shaft oscillates the pushing pawl and drives the cam disk through the driven ratchet step by step in a reduced timing speed.

Claims9

Dependent claims

An electromechanical program timer with delay sections capable of actuating at least a contact switch for controlling electrical actuators connected thereto, comprising at least:

driving means for providing a rotational power;
a driving shaft, driven by said driving means, having an eccentric shaft and a driving gear;
a main driven gear, having at least a missing gear portion, rotationally mounted adjacent to said driving shaft for being engaged with said driving gear and driven thereby in a major timing speed;
a cam unit, fixed to said main driven gear, having at least a circular cam track for actuating said contact switch, and a driven ratchet formed with a plurality of ratchet teeth;
and
a pushing pawl, having one end pivotally mounted on said eccentric shaft, and a pawl end engaged with ratchet teeth of said driven ratchet;
when said main driven gear being driven to said missing gear portion, said pushing pawl activated by said eccentric shaft pushes said driven ratchet moving in a relatively lower timing speed.

4 more elements

Dependencies are inferred from the claim text.