In some examples, a controller receives impedance sensor values from an impedance sensor in a printhead, determines whether the impedance sensor values correlate to a production of an effective drive bubble for the printhead, and issues a command to modify a firing parameter for a fluid ejector of the printhead based on the impedance sensor values.

A joint system includes flow paths coupled to a fluid device which handles a fluid, first and second electrodes separately provided to the flow paths to electrically make contact with the fluid in the flow paths, and a detection circuit which detects whether the fluid passing through the fluid device is present or absent. The detection circuit measures a degree of electrical conductivity between the flow paths by using the first and second electrodes and detects whether the fluid passing through the fluid device is present or absent in accordance with the degree of electrical conductivity between the flow paths.

A solution property sensor is provided and has: a substrate, a temperature sensing element, an electrical conductivity sensing element, a pH value sensing element, and a reference electrode. The solution property sensor utilizes different sensing elements to sense various solution properties, and all of these sensing elements can be electrically connected and fixed to conductive patterns on the same substrate, thereby facilitating mass production in the industry or reducing production difficulty.

A solution property sensor is provided and has: a substrate, a temperature sensing element, an electrical conductivity sensing element, a pH value sensing element, and a reference electrode. The solution property sensor utilizes different sensing elements to sense various solution properties, and all of these sensing elements can be electrically connected and fixed to conductive patterns on the same substrate, thereby facilitating mass production in the industry or reducing production difficulty.

A method of characterizing a fluid flow by an alternating magnetic field flow meter, comprising determining a flow rate of a fluid flowing through a conduit by generating a first magnetic field to move a magnetic token along a direction of a flow path of a fluid flowing through a conduit, detecting a first electrical signal based on the movement of the magnetic token, generating a second magnetic field to move the magnetic token opposite to the direction of the flow path, detecting a second electrical signal based on the movement of the magnetic token, and determining a conductivity of the fluid flowing through the conduit by generating a current along the flow path and detecting a third electrical signal based on the current generated along the flow path, and determining a conductivity measurement of the fluid flow based on the detected third electrical signal.

A method of characterizing a fluid flow by an alternating magnetic field flow meter, comprising determining a flow rate of a fluid flowing through a conduit by generating a first magnetic field to move a magnetic token along a direction of a flow path of a fluid flowing through a conduit, detecting a first electrical signal based on the movement of the magnetic token, generating a second magnetic field to move the magnetic token opposite to the direction of the flow path, detecting a second electrical signal based on the movement of the magnetic token, and determining a conductivity of the fluid flowing through the conduit by generating a current along the flow path and detecting a third electrical signal based on the current generated along the flow path, and determining a conductivity measurement of the fluid flow based on the detected third electrical signal.

A flow measuring device includes a housing including a bypass passage and a flow sensing chip located in the bypass passage and including a sensing surface portion. A throttle portion that is a part of a flowing passage wall facing a sensing surface portion throttles a cross-sectional area of a bypass passage. A position where the throttle portion starts is referred to as a start point position, and a position of the throttle portion where a distance between a gravity center of the sensing surface portion and the throttle portion is shortest is referred to as an end point position. The start point position and the end point position define an imagination line, and the imagination line and the flowing direction define an angle that is in a range from 0 degrees to 20 degrees.

A fluid property detecting device includes a detection portion configured to detect electric characteristics of a detection target fluid, a calculation portion configured to calculate a property value of the detection target fluid, and a storage portion configured to store the property value calculated by the calculation portion. The storage portion stores, in advance, as the reference detection value, the detection value of the electric characteristic of a reference fluid detected by the detection portion, and the calculation portion calculates the property value of the detection target fluid on the basis of a value obtained by subtracting the reference detection value from a detection value of the detection target fluid.

Multiphase flowmeters and related methods are disclosed herein. An example apparatus includes a flowmeter and a fluid conduit to provide a flow path for a fluid relative to the flowmeter. The example apparatus includes a sensor coupled to the fluid conduit to generate data indicative of at least one of a presence, an absence, or a mass flow rate of solids in the fluid during flow of the fluid through the fluid conduit. The example apparatus includes a processor. The sensor is to be communicatively coupled to the processor. The processor is to selectively determine flow rates for one or more phases of the fluid based on data generated by the flowmeter and a first algorithmic mode or a second algorithmic mode selected based on the sensor data.

Multiphase flowmeters and related methods are disclosed herein. An example apparatus includes a flowmeter and a fluid conduit to provide a flow path for a fluid relative to the flowmeter. The example apparatus includes a sensor coupled to the fluid conduit to generate data indicative of at least one of a presence, an absence, or a mass flow rate of solids in the fluid during flow of the fluid through the fluid conduit. The example apparatus includes a processor. The sensor is to be communicatively coupled to the processor. The processor is to selectively determine flow rates for one or more phases of the fluid based on data generated by the flowmeter and a first algorithmic mode or a second algorithmic mode selected based on the sensor data.