Leuze Offers New Ultrasonic Sensors for Position and Fill Applications

Leuze, an industry leader specializing in sensing and networking technologies, recently announced that two new lines of ultrasonic sensors, the HTU200 and the DMU200, are now available. These sensors measure distance and will likely see use in packaging, filling, and quality control type applications, designed to work in virtually any industrial environment.

 

What is an Ultrasonic Sensor?

Ultrasonic sensing is used to determine the distance between the sensor and a surface. Most of these types of sensors, including the HTU200 and DMU200 series, are active, meaning they emit a high-frequency sound signal and listen for the reflection. Based on the time it takes for the signal to leave the sensor, reflect, and then return, the distance can be calculated. While other systems, such as lasers and light, can do this fairly well in many cases, ultrasonic sensors are capable of performing this task in any ambient lighting condition, and can detect transparent or very optically reflective objects. For example, sensing panes of glass is difficult for optical reflection, but no problem for sound wave reflection.

In spite of these advantages, ultrasonic sensors are often challenged by dusty environments, rough surfaces, and some curved and angled geometries. Dusty environments often send inconsistent false readings when the sound wave is reflected by the dust particles rather than the surface. However, optical sensors are far more sensitive to the scattering of light in contact with humidity and dust, so ultrasonic sensors are often called upon in these situations.

 

Leuze’s new HTU200 and DMU200 series of ultrasonic sensors. Image used courtesy of Leuze

 

Angled or rough surfaces may reflect some of the signal, but the remainder is scattered and may not return to the detector. Particularly in the case of rough surfaces, there can be several distances that reflect the wave at slightly different moments, so the distance is impossible to calculate.

Ultrasonic sensors may not be applicable for every scenario, but they remain a reliable technology for a great many situations.

 

Leuze’s New HTU200 and DMU200

The product announcement highlights two new offerings, the HTU200 and DMU200 series. Each of these lines has multiple products, capable of fitting a variety of needs, with different sensor widths, beam widths, and detection distances. Depending on the model, these sensors can detect objects as close as 0.1 meters (about 4 inches) or as far away as 6 meters (almost 20 feet). The product lines provide switching (discrete) outputs, as well as measuring (analog) output modes within the same sensor. Some are equipped with IO-Link capabilities as well.

 

A wider beam may be more suitable for this application, as it will not be fooled by the slots in the boxes. Image used courtesy of Leuze

 

Wide beam sensors are useful for detecting large surfaces with lots of small features, such as holes and slots. Thin beams can detect small objects, but can be fooled by holes, slots, and some surface topography. Consider a cardboard cutting operation that makes stacks of foldable boxes. A wide beam will detect the flat cardboard, but a thin beam might land in a hole and send a false signal. However, a thin beam might be more useful for filling grain hoppers, where the surface will not be flat, and the highest point right in the center is the area of interest.

Perhaps the greatest feature of these new products is their ability to function in dusty or humid environments. Many sensors (usually optical) are affected by dust or moisture, which can limit their ability to see long distances or function in certain industrial environments.

 

Leuze sensors can detect distance and fill level, even in dusty environments. Image used courtesy of Leuze

 

Ultrasonic Sensing

In general, ultrasonic sensing is a great way to measure distance in a contactless fashion. They can check fluid levels or fill levels, count flat sheets, Measure product roll diameters, and perform numerous other packaging or compliance tasks. The Leuze HTU200 and DMU200 series provide advanced signal capabilities paired with reliable ultrasonic sensing, making possible more accurate measurements in environments where measurement tasks had previously been a major hurdle.