Provided are sampling pumps and gas analyzers using the sampling pumps. The sampling pump may include at least one reciprocating pump set and a control system. Each reciprocating pump set can include two reciprocating pumps. The control system can output drive signals for controlling reciprocating drawing and compressing operations of the reciprocating pumps, where the control system may be designed to output the drive signals that cause the two reciprocating pumps within the same set to provide opposing impact directions at the same time.

A vacuum pump comprises rotor elements arranged in a suction chamber. An outlet duct is connected to an exhaust pipe. For the purpose of silencing, sound expansion spaces are provided in the outlet duct, which are integrated into the pump housing. Alternatively or in addition to these sound expansion spaces, sound expansion spaces may be provided in an inlet duct which is used for the inlet of gas ballast, said sound expansion spaces being preferably likewise integrated into the pump housing.

Provided is a metal diaphragm that can be easily processed and manufactured at low cost. Therefore, a metal diaphragm (91, 92) of the present invention is configured such that a curvature radius r1 of a first curved portion 911 located on the outermost side in the radial direction (outer side in the left-right direction in FIG. 5) is minimized among a flange portion (91a, 92a) and curved portions (911, 912) that are located on the radially inner side of the flange portion (91a, 92a) and curved from the flange portion (91a, 92a) to one side (upper side in FIG. 5).

A linear compressor includes a piston that reciprocates on a spring central axis extending in an axial direction and a spring that axially elastically supports the piston. The spring includes a plurality of spring strands. The spring strands each include a spring body spirally extending along a spring central axis C, a front spring link forming an end of the spring body by extending from a side of the spring body, and a rear spring link forming the other end of the spring body by extending from the other side of the spring body. Of the spring strands, the front spring links are disposed axially in the same plane P1 and the rear spring links are disposed axially in the same plane P2.

A motor control device includes a drive control device that controls turning on/off of a motor, and a voltage obtaining device that obtains a voltage across terminals of the motor. The drive control device determines whether or not the motor drive signal is OFF (ST01). If the determination is Yes, the drive control device determines whether or not the voltage across the terminals, which is obtained by the voltage obtaining device, has decreased and reached a target voltage (ST02). If the determination at ST02 is Yes, an ON time is set on the basis of the immediately preceding OFF time (ST03), and the motor drive signal is switched from OFF to ON (ST04). After the ON time elapses, the motor drive signal is switched from ON to OFF (ST05). Low-rotational-speed motor control can be performed while suppressing heat generation in a motor relay.

A dual pumping fluid pump which significantly reduces vibration and noise generation. When a cam installed on a rotating shaft of a single electric motor is rotated, a pair of first and second diaphragms installed in connection to an eccentric shaft portion formed on both the left and right sides of the cam alternatingly rise and descend in opposite directions and cause first and second intake check valves and first and second discharge check valves provided on a fluid passage box integrally and connectedly installed on the top surface of a pump housing to open or close first and second intake holes and first and second discharge holes to admit fluid through a fluid inlet and simultaneously discharge fluid through a fluid outlet, so that the simultaneous effects of the intake pressure and discharge pressure of fluid causes pressure balancing to occur.

A mini air pump which includes a diaphragm, a bladder base provided with penetrating bladder holes and air inlet channels, a pump body having a valve seat and a pump cover, an air inlet valve, an air outlet valve, a relief valve and a preload member is revealed. The valve seat is stacked over the diaphragm. An exhaust chamber and a spring chamber are constructed by the valve seat and the pump cover. The valve seat has exhaust channels communicating with the bladder cavity. A communicating return channel is constructed by the diaphragm, the bladder base and the valve seat. The return channel is communicating with the air inlet channel but not communicating with the spring chamber. A spring of the preload member applies a preload to the relief valve. Thereby the relief valve acts more accurately and the mini air pump is more stable in use.

An oil suction pump contains: an oil storage cylinder, a pumping mechanism, and a cap. The pumping mechanism includes a body, a drive rod, a plug, and a pressure relief valve. The cap is disposed on the body and the oil storage cylinder, and the cap includes a connector. The drive rod has a press lever, the cap further includes a first air conduit, a first one-way valve assembly, and a second air conduit. The second air conduit has an inlet segment, an outlet opposite to the inlet segment, and a pump segment defined between the inlet segment and the outlet segment and communicating with the oil storage cylinder. The cap further includes a second one-way valve assembly accommodated in the oil storage cylinder and connected with the pump segment, and the second conduit accommodates a pressure reducing valve.

Illustrative embodiments of diaphragm pumps including a sensor mount are disclosed. In one illustrative embodiment, a diaphragm pump may include a shaft disposed within a pump housing and coupled to at least one diaphragm, a mount removably attached to the pump housing and having a sensor receptacle, and a proximity sensor received in the sensor receptacle of the mount such that a sensing end of the proximity sensor is flush with an end of the sensor receptacle nearest the shaft.

End element for the stator of an electric motor of a hermetically sealed refrigerant compressor. The end element includes at least one isolating element, having a ring-like core, to cover an axial end portion of the stator and to isolate a stator core and stator windings. The end element includes several spring holders that extend radially outside the isolating element, each spring holder being adapted to hold a spring for supporting the electric motor in a housing of the hermetically sealed refrigerant compressor. The spring holders are oriented parallel to the axis of the isolating element and an insertion part of each spring holder extends in a first axial direction beyond the neighboring area of the isolating element. The spring holders and the isolating element are integral parts of the end element. The spring holders are tiltable so that an extended part of a spring holder tilts radially inwards.