Serial release mechanism and drainage monitor embodying the same

A discharge monitor comprising, in combination:

• means supplying a liquid to be distributed;
• first and second storage chambers for receiving said liquid;
• first and second collapsible elastic tubes for conducting said liquid to said chambers;
• first and second actuators slidable in a frame between withdrawn positions and working positions in which they collapse said tubes to prevent liquid from flowing therethrough;
• resilient means urging said second actuator into said working position;
• trigger means, including a latch tab carried by said second actuator and a trigger resiliently pivoted to said frame, for releasably retaining said second actuator in said withdrawn position;
• trigger release means including a shaft of noncircular cross section and a saddle having an operating finger, said saddle being rotatable with said shaft and slidable therealong between a first position, in which said finger is aligned with said trigger, and a second position, in which said finger is not aligned with said trigger;
• disabling means, including a saddle spring, resiliently urging said saddle along said shaft into said second position, so that rotation of said shaft does not cause release of said trigger;
• means for displacing said first actuator into its working position to prevent liquid flow to said first chamber;
• and override means including a shifter spring carried by said first actuator and said frame, and effective when said first actuator is in working position to displace said saddle into said first position, so that subsequent rotation of said shaft causes said finger to release said trigger, to prevent liquid flow to said second chamber.