Techniques for measuring vacuum pressure using a memristor element are described. A vacuum sensor can include a memristor element having a semiconductor substrate, a memristive material layer, and a conductive electrode. The off-state resistance of the memristor element can be sensitive to changes in ambient pressure at the element. The off-state resistance of the memristor element may also exhibit a well-defined increase at pressures below a threshold pressure. Measurement of the off-state resistance may be obtained with low power consumption and without changing the resistance or switching the state of the memristor element. The measurements may be used to both determine a leak rate of the ambient pressure within the volume of interest and determine if the sensor is exposed to vacuum pressure below the threshold pressure.

Techniques for measuring vacuum pressure using a memristor element are described. A vacuum sensor can include a memristor element having a semiconductor substrate, a memristive material layer, and a conductive electrode. The off-state resistance of the memristor element can be sensitive to changes in ambient pressure at the element. The off-state resistance of the memristor element may also exhibit a well-defined increase at pressures below a threshold pressure. Measurement of the off-state resistance may be obtained with low power consumption and without changing the resistance or switching the state of the memristor element. The measurements may be used to both determine a leak rate of the ambient pressure within the volume of interest and determine if the sensor is exposed to vacuum pressure below the threshold pressure.

The present invention discloses an airtight test apparatus and an airtight test method using the same for testing an airtight property of a case assembled with a plurality of additional members thereon in which the case has through holes corresponding to the additional members. The airtight test apparatus comprises a base, a top plate and a plurality of sealing members selectively and detachably disposed on the top plate. The top plate is capable of moving towards the base to allow the sealing members to correspondingly seal the through holes. During test, the case is placed on the base to form a gas chamber, an air-extracting is performed for the gas chamber and an air pressure is detected. When the detected air pressure is larger than a predetermined value, the sealing members can be selectively utilized to seal the corresponding through holes for determining which through holes have poor airtight property.

An apparatus (100) for testing suction cups (138) mounted on a track (162) is disclosed. The apparatus (100) comprises a base (102) comprising a first surface (104) and a second surface (106) opposite the first surface (104). The apparatus further comprises ports (108) penetrating the base (102) from the first surface (104) to the second surface (106) and vacuum sensors (112) pneumatically coupled to the ports (108). The ports (108) in the base (102) are arranged in a geometric pattern (110).

An apparatus (100) for testing suction cups (138) mounted on a track (162) is disclosed. The apparatus (100) comprises a base (102) comprising a first surface (104) and a second surface (106) opposite the first surface (104). The apparatus further comprises ports (108) penetrating the base (102) from the first surface (104) to the second surface (106) and vacuum sensors (112) pneumatically coupled to the ports (108). The ports (108) in the base (102) are arranged in a geometric pattern (110).

An inspection method for inspecting the water resistance of an electronic device is provided, including providing a vacuum generator, using the vacuum generator to pump air out of the electronic device, stopping the pumping of air out of the electronic device when the air pressure in the electronic device is less than a predetermined pressure value, measuring the air pressure in the electronic device as a first pressure value after the pumping of air out of the electronic device has been stopped for a predetermined time, calculating the pressure difference D by subtracting a second pressure value from the predetermined pressure value, calculating the pressure difference d by subtracting the second pressure value from the first pressure value, and determining whether the electronic device is waterproof or not according to the pressure differences D and d.

An inspection method for inspecting the water resistance of an electronic device is provided, including providing a vacuum generator, using the vacuum generator to pump air out of the electronic device, stopping the pumping of air out of the electronic device when the air pressure in the electronic device is less than a predetermined pressure value, measuring the air pressure in the electronic device as a first pressure value after the pumping of air out of the electronic device has been stopped for a predetermined time, calculating the pressure difference D by subtracting a second pressure value from the predetermined pressure value, calculating the pressure difference d by subtracting the second pressure value from the first pressure value, and determining whether the electronic device is waterproof or not according to the pressure differences D and d.

The die casting machine includes: a sleeve with tubular shape, the sleeve communicating with inner space of a die casting mold; a plunger disposed in the sleeve, the plunger moving along a central axis of the sleeve; a sensor for measuring pressure of the inner space of the die casting mold; and a controller programmed to perform an airtight inspection of the die casting mold, during outside a molding period of a die casting product by the die casting machine; in the airtight inspection, wherein the controller is programmed to: pump gas in the sleeve to the inner space, or suck gas in the inner space into the sleeve, by moving the plunger in a clamping state, wherein the clamping state is a state of the die casting mold being clamped; obtain the pressure of the inner space from the sensor; determine an abnormality in airtightness of the die casting mold using measurement result of the pressure of the inner space.

The die casting machine includes: a sleeve with tubular shape, the sleeve communicating with inner space of a die casting mold; a plunger disposed in the sleeve, the plunger moving along a central axis of the sleeve; a sensor for measuring pressure of the inner space of the die casting mold; and a controller programmed to perform an airtight inspection of the die casting mold, during outside a molding period of a die casting product by the die casting machine; in the airtight inspection, wherein the controller is programmed to: pump gas in the sleeve to the inner space, or suck gas in the inner space into the sleeve, by moving the plunger in a clamping state, wherein the clamping state is a state of the die casting mold being clamped; obtain the pressure of the inner space from the sensor; determine an abnormality in airtightness of the die casting mold using measurement result of the pressure of the inner space.

Methods of balancing a workpiece, in which the workpiece is rotated about an axis of rotation. The forces and/or torques that result from an unbalance of the workpiece during the rotation of the workpiece are measured, and material is removed from the workpiece to reduce the unbalance. The method includes removal of material from the rotating workpiece during measuring or as the workpiece is continuously rotated between measuring and material removal.