In a leak detector of the by-pass check-valve type, as described in my U.S. Pat. No. 3,817,087, having a check-valve blocking lever that is pivotal by a leak flow through the by-pass, the leak flow being directed against the blocking lever through a nozzle mounted in slidable cooperation with a sleeve for concentrating the force of the leak flow and for following the blocking lever as it is pivoted thereby, thus maintaining the maximum force thereagainst, and thereby indicating a leak by restric...

An example of an apparatus for detecting the lowering of a top surface of a liquid includes a housing that has a housing hole, and an insertion member attached to the housing. A dowel is inserted into the housing hole, and a float is attached to the dowel. A detector switch that has an actuator arm is also attached to the housing, with the actuator arm of the detector switch located proximate a first end of the dowel. An audio transducer is attached to the housing, to sound an alarm if the first...

A device for detecting leaks in containers that are open to the effects of rain and/or evaporation comprising an outer cylinder or container partially submerged in a container or vessel to be measured, such as, a swimming pool, three adjustable legs attached to the bottom of the outer cylinder, an inner tube having a bottom edge fastened to the bottom, an outer, floating guide cap, and an inner floating indicating rod. The device is placed in a swimming pool and submerged to a selected level. Th...

A leak detector comprises a high vacuum envelope connected with a vacuum pump to bring the vacuum envelope to a pressure sensibly lower than ambient pressure. At least a portion of the envelope is separated from an external environment through a quartz membrane associated with an electrical resistor, which heats the membrane to a sufficient temperature in order to make it permeable to a corresponding test gas (in particular, helium). In operation, an electronic control unit detects variations in...

Methods of and apparatus for detecting the leakage of fluids from containment vessels. The tank is surrounded by or lined with a generally fluidtight envelope, and a vacuum is applied to hold the envelope against the tank and thereby control and limit to a very small volume the space between the primary containment, be it the vessel or liner, and the envelope. Fluids escaping from the containment vessel collect in that space. Collected fluids are evacuated; and fluid withdrawal information is pr...

Apparatus for detecting leaks in fuel storage tanks. A float suspended in the tank liquid determines liquid levels and transmits the liquid level information via an infrared beam to a probe processor in the upper portion of the tank. The probe processor stores a plurality of level indications for subsequent uploading to an external computer which analyzes the level information to generate leakage rate information.

A leak sensor and a leak sensing system are provided. The leak sensor preferably includes a fluid sensing member that is capable of sensing and indicating the presence of a fluid leaked from a fluid storage or transport member. The leak sensor further preferably includes at least two wires communicating with the fluid sensing member. The wires are preferably configured to be short-circuited when they contact the fluid leaked from the fluid storage or transport member. An electrical signal corres...

A portable leak detector includes a housing having an inlet and an outlet each in fluid communication between an interior and an exterior of the housing. A gas sensor, having a property that changes in response to exposure of the gas sensor to one or more gases, is positioned in fluid communication with the interior of the housing via the inlet thereof. The leak detector includes a probe lamp, a plurality of first indicator lamps supported by the housing and a speaker supported by the housing. A...

A leak tester is used to perform a leak test on a work such as a wheel by detecting trace gas being leaked from the work. Herein, the work is installed in a chamber and is tightly held between seals. A leak tester seal is constructed using a work seal base, on which a number of channels are formed like circular rings, which are sequentially arranged with equal intervals. For example, an interval of distance between centers of adjoining channels is set at 1.27 cm to cope with different kinds of t...

A leak detector employing an ion-conducting membrane is disclosed. A labelled-gas ion conducting membrane which employs a high vacuum on one side is used to detect very small quantities of said labelled-gas flowing through a minute fissure in a part or device to be tested for leaks. The labelled-gas ion conducting membrane is biased with direct current voltage to drive the labelled-gas ions through the membrane away from the high vacuum side.