German QASS sensors, QASS models, QASS prices

QASS sensors measure the operating speed of the object under test and convert it into an output signal. Speed sensors include linear speed sensors and rotational speed sensors. With technological development, traditional measurement equipment can no longer meet current needs and is gradually being phased out, while laser speed sensors are widely used. They play an important role in product manufacturing processes; by connecting to a computer, they enable automated and intelligent measurement control of the object under test. This is the product of the combination of modern measurement technology and computer technology.

QASS sensor classification

1) Laser speed measurement: With the rise of precision manufacturing and the need for cost savings, non-contact speed sensors are gradually replacing contact speed sensors. The most common and high-precision non-contact laser speed sensor on the market today is the ZLS-Px aberration speed sensor. The aberration speed sensor has two ports: one emission port that emits a LED light source, and one high-speed imaging port that achieves CCD area high-speed imaging comparison. By comparing images at two points in time within an extremely short period, the distance moved by the object under test is determined, and the sensor's internal algorithm outputs the speed of the object in real time. As shown in the figure, (1) is the LED light emission port, (2) is the camera reception port, (3) and (4) are terminal blocks, and (5) are mounting screw holes. (1) The LED light emission port emits laser light toward the object under test, which reflects to the (2) camera reception port. After receiving the signal, it is transmitted to the signal processor, which calculates the speed using an algorithm. The ZLS-Px aberration speed sensor can simultaneously measure speed and length in two directions. It can detect not only whether the object under test has stopped but also its direction of motion. Mount the sensor on a stable bracket to ensure that the rotating object does not generate excessive vibration during rotation, thereby allowing measurement of the rotation angle and rotational speed of the object under test. 2) Radar speed measurement: Traditional speed measurement mostly focuses on rotational motion speed and linear motion speed. However, there are many irregular speed measurement scenarios in industrial automation, such as athlete speed measurement, traffic vehicle speed measurement, and golf ball speed measurement. Radar speed sensors can meet these requirements.

QASS sensor principle

A transmissive speed sensor consists of a slotted or notched disk, a light source, and a phototube. When the disk rotates with the shaft under test, light can only reach the phototube through the holes or notches. When the phototube is illuminated, its reverse resistance is very low, outputting an electrical pulse signal. When the light source is blocked by the disk, the phototube's reverse resistance is very high, and no signal is output. Thus, the rotational speed of the shaft under test can be measured based on the number of holes or notches on the disk. The usual number of disk holes or notches is unclear in the source, so the photoelectric converter outputs 60 pulse signals per revolution of the shaft under test. If the time base signal of the electronic counter is set to 1s, the rotational speed of the shaft under test can be read directly. The principle of a reflective speed sensor is similar to that of the transmissive type, converting changes in sensed light into changes in electrical signals via a phototube, but it obtains pulse signals through light reflection. Typically, reflective material is attached to the measurement area of the shaft under test to form a reflective surface. Common reflective materials include specialized speed-measuring reflective tape (adhesive tape); aluminum foil or other reflective materials can also be used, and sometimes white paint is applied to the measurement area as a reflective surface. The projector and reflective surface must be properly configured, typically with a distance of 5-15M between them. When the shaft under test rotates, the photoelectric element receives pulsed light and outputs corresponding electrical signals to the electronic counter, thereby measuring the rotational speed of the shaft. The waveform of the output signal from photoelectric speed sensors is relatively regular, close to a standard square wave, with almost no interference signals generated. However, vibration in transmissive types can reduce the lifespan of the light source, making them unsuitable for conditions with strong vibration. Reflective types have no mechanical connection with the shaft under test and are convenient to use.

QASS sensor industry applications

1) Modern vehicles are generally equipped with engine control, autonomous driving, ABS, TRC, automatic door locking, active suspension, guidance systems, electronic instruments, and other devices, all of which require vehicle speed signals. Therefore, the accuracy and stability of the output signal from the vehicle speed sensor will greatly affect these control units. Automotive speed sensors often adopt a Hall-effect structure. A Hall speed sensor is a magnetoelectric sensor based on the Hall effect, featuring high sensitivity to magnetic fields, stable output signals, high frequency response, strong anti-electromagnetic interference capability, simple structure, and ease of use. It mainly consists of permanent magnets with a specific number of pole pairs (generally 4 or 8 pairs), Hall elements, a rotating mechanism, and input/output connectors. Its working principle is that when the sensor's rotating mechanism rotates under external drive, it drives the permanent magnet to rotate, causing periodic changes in the magnetic field passing through the Hall element. This causes changes in the output voltage of the Hall element, which is processed by subsequent circuits to form a stable pulse voltage signal as the output of the speed sensor. Key electrical technical parameters of Hall-structure speed sensors include high output voltage, low output voltage, duty cycle, period, rise time, fall time, and pulses per period. To ensure product performance reliability, these parameters must be quantitatively tested before factory shipment. Test systems featuring integration and intelligence, efficient automatic measurement, software calculation, and graphical or tabular display of results are increasingly favored by automotive speed sensor manufacturers. A comprehensive testing device has been developed for performance measurement of common Hall-effect vehicle speed sensors. Considering costs, the high-speed counter port of a microprocessor is used for data acquisition from the vehicle speed sensor, and software control is used to calculate and graphically display the acquired data. The completed testing device offers advantages such as high testing accuracy, reliable data communication, a user-friendly graphical interface, strong anti-interference capability, simple and intuitive testing process, and low system development cost. It has good market promotion potential, so speed sensors will have huge application prospects in vehicle speed detection. 2) Speed sensors for belt conveyors use Hall sensors, which are sensors that utilize the Hall effect to achieve magnetoelectric conversion. The Hall effect was discovered in 1879 and has a development history of over 100 years, but its application gained attention and widespread adoption in the 50s of this century due to the rapid development of microelectronics, leading to the continuous development of various Hall elements. China began increasing research on Hall elements in the 20s of the 70 century. After nearly several decades of research and development, it is now possible to produce Hall elements with various performances, such as standard type, high sensitivity type, low temperature coefficient type, temperature/magnetic measurement type, and switch-type Hall elements. Due to the characteristics of Hall sensors, such as high sensitivity, good linearity, high stability, small size, and high temperature resistance, they are widely used in various industrial fields, including non-electrical quantity measurement and automatic control, computer devices, and modern military technology.

Weidou Intelligent Technology specializes in selling German QASS sensors, QASS proximity sensors, QASS distance sensors, QASS vision sensors, QASS displacement sensors, QASS torque sensors, QASS speed sensors, QASS photoelectric sensors, QASS position sensors, QASS angle sensors, QASS tactile sensors, QASS temperature sensors, QASS pressure sensors, QASS flow sensors, QASS level sensors, QASS motion sensors, and QASS process sensors. Original imports from Germany. Welcome inquiries and orders from users.