Patent attributes
A liquid level alarm is placed in a tank having a bottom and has a weight, a floating box, an alarm circuit and a cord. The weight is placed on the bottom of the tank. The floating box has a top recess, a passage, a slide and a top cover. The passage communicates with the top recess. The slide is mounted slidably in the passage. The alarm circuit is mounted in the top recess in the floating box and has two contacts, an alarm element, a switch and a spring. The switch is connected to the slide. The spring is connected to the top cover and holds the switch open. The cord is connected to the weight and the slide. When the floating box moves above a predetermined level, the switch with the slide moves down and makes contact with the contacts to activate the alarm element.