Provided is a thermal flow meter that can be prevented from being eroded due to adhesion of water or like to a cut end portion of the lead exposed from the mold resin of the circuit package. A thermal flow meter 300 of the present invention is a thermal flow meter having a circuit package 400 formed by mounting a detection element 518 on leads 544 and 545 supported by a support frame 512, sealing with a mold resin, and cutting off the support frame 512, wherein cut end portions 544a and 545a of the leads 544 and 545 exposed from the mold resin of the circuit package 400 by cutting off the support frame 512 is covered by a covering portion 371.

Provided is a thermal flow meter that can be prevented from being eroded due to adhesion of water or like to a cut end portion of the lead exposed from the mold resin of the circuit package. A thermal flow meter 300 of the present invention is a thermal flow meter having a circuit package 400 formed by mounting a detection element 518 on leads 544 and 545 supported by a support frame 512, sealing with a mold resin, and cutting off the support frame 512, wherein cut end portions 544a and 545a of the leads 544 and 545 exposed from the mold resin of the circuit package 400 by cutting off the support frame 512 is covered by a covering portion 371.

A flow rate detecting device according to an aspect of the invention includes a pipe which includes a bent portion and through which fluid is passed; two temperature detecting portions which detect the temperature of the fluid in the pipe; and a temperature changing portion which changes the temperature of the fluid in the pipe at an intermediate position in which distances between each of the two temperature detecting portions and the intermediate position are equidistant. The intermediate position is positioned in the bent portion in the pipe, and the bent portion is formed to be line symmetric with respect to a straight line passing through the intermediate position.

Provided is a thermal type flowmeter in which contamination of a sensor element is reduced. The flowmeter includes a sensor element including a heating resistor formed in a thin film part, the thin film part being provided on a diaphragm formed on a substrate; a support member to locate the sensor element thereon; a secondary channel that includes part of the support member and takes in part of intake air flowing through an air intake pipeline; and a guide member provided on the support member or the sensor element that lies on a line L that extends along an air flow in the secondary channel and passing over the thin film part, the guide member allowing fine particles to be guided in a direction away from the line L, the fine particles coming together with an air flow along the surface of the support member or the sensor element.

Provided is a thermal type flowmeter in which contamination of a sensor element is reduced. The flowmeter includes a sensor element including a heating resistor formed in a thin film part, the thin film part being provided on a diaphragm formed on a substrate; a support member to locate the sensor element thereon; a secondary channel that includes part of the support member and takes in part of intake air flowing through an air intake pipeline; and a guide member provided on the support member or the sensor element that lies on a line L that extends along an air flow in the secondary channel and passing over the thin film part, the guide member allowing fine particles to be guided in a direction away from the line L, the fine particles coming together with an air flow along the surface of the support member or the sensor element.

To improve measurement stability of a flow rate detection unit in a physical quantity detection device, a periphery of a synthetic resin material is provided with a protruding section protruding to a cover side. A physical quantity detection device includes a housing, a front cover fixed to the housing, a circuit board housed in the housing, a flow rate detection unit that detects, in a sub-path, the flow rate of a gas to be measured by being attached to the circuit board, a connecting wire that electrically connects the flow rate detection unit to the circuit board, and a synthetic resin material that seals a connecting wire-included connection portion between the circuit board and the flow rate detection unit, the front cover having a protruding section covering at least a part of the synthetic resin material by protruding into the sub-path.

A mass flow controller includes at least one conduit having a fluid inlet and a fluid outlet, the conduit defining a flow path along which the fluid flows. The mass flow controller also includes a modified inlet block having an inlet aperture, an inlet channel, and a reservoir fluidly coupled to the inlet channel and the conduit that enhances flow through the controller and improves rate-of-decay measurements. The mass flow controller includes at least one flow sensor that generates a flow sensor signal that is proportional to the mass flow rate of the fluid through the conduit. The mass flow controller includes a control subsystem coupled to a flow sensor and a valve assembly to control flow through the conduit.

A mass flow controller includes at least one conduit having a fluid inlet and a fluid outlet, the conduit defining a flow path along which the fluid flows. The mass flow controller also includes a modified inlet block having an inlet aperture, an inlet channel, and a reservoir fluidly coupled to the inlet channel and the conduit that enhances flow through the controller and improves rate-of-decay measurements. The mass flow controller includes at least one flow sensor that generates a flow sensor signal that is proportional to the mass flow rate of the fluid through the conduit. The mass flow controller includes a control subsystem coupled to a flow sensor and a valve assembly to control flow through the conduit.

In order to provide a thermal flow meter for improving workability of a flow rate measurement device having a temperature measurement function for the measurement target gas and measurement accuracy for measuring a temperature, the thermal flow meter is structured such that a flow rate measurement circuit package having a protrusion for measuring a gas temperature is formed through resin molding. An inlet port opened to the upstream side of the measurement target gas is formed, a protrusion is arranged inside the inlet port, an inlet port and an outlet port are formed in the front and rear covers along the protrusion, and the measurement target gas received from the inlet port flows along the protrusion. Since the measurement target gas subjected to the measurement flows along the protrusion, it is possible to reduce influence of the heat from other heat resources and improve measurement accuracy.

In order to provide a thermal flow meter for improving workability of a flow rate measurement device having a temperature measurement function for the measurement target gas and measurement accuracy for measuring a temperature, the thermal flow meter is structured such that a flow rate measurement circuit package having a protrusion for measuring a gas temperature is formed through resin molding. An inlet port opened to the upstream side of the measurement target gas is formed, a protrusion is arranged inside the inlet port, an inlet port and an outlet port are formed in the front and rear covers along the protrusion, and the measurement target gas received from the inlet port flows along the protrusion. Since the measurement target gas subjected to the measurement flows along the protrusion, it is possible to reduce influence of the heat from other heat resources and improve measurement accuracy.