Sensor Design Engineering Services

Posted by Seta Davidian on Sep 26, 2016 11:48:16 AM

gauge.jpgServoflo, a premier supplier of pressure, mass flow, environmental sensors and micropumps,  is pleased to announce expansion of its design engineering services for custom sensor development. The objective is to be a primary resource for customers who require modification or customization of sensors and how they are integrated into product designs. Services include but are not limited to:

  • adding flex to a sensor
  • creating a custom flow path for mass flow sensors
  • adding Wi-Fi or BlueToothâ„¢ capabilities to a sensor
  • adding a display
  • custom packaging enclosures
  • hybrid circuit design

flex.jpgThis one-stop solution provides customers with efficient and reliable design expertise without having to manage multiple vendors as well as streamlining assembly. Purchasing a complete solution saves customers money and time. Often, a bill of materials is reviewed and pressure is put on individual component costs. This strategy neglects the labor needed to inspect, integrate, and test various separate components such as a sensor element, cable, and package. A complete sensor solution can actually reduce overall bill of materials and labor costs. This sensor design strategy is also important for customers who may not have design expertise in these areas.

Specific application examples include:

  • Creation of a pressure gauge with display and enclosure
  • Hybrid circuit design to integrate a pressure sensor and electronics for better protection in a high temperature and high humidity environment
  • Adding a flex cable to a standard board level sensor to eliminate the assembly and testing steps at installation
  • Customized sensor calibration and output to meet a specific customer requirement
  • Design of a special flow path in a mass flow sensor for medical equipment
  • Design custom electronics to create a pressure or mass flow switch (or other environmental sensor)

If you have a special requirement you would like to discuss, please utilize the button below for fastest response.

 Discuss a custom solution

Topics: Ceramic Pressure Sensors, Pressure Sensors, Mass Flow Sensors

Mass Flow Sensors for Anesthesia Machines

Posted by Seta Davidian on Apr 7, 2016 1:23:50 PM

Mass Flow Sensor FS4008General anesthesia machines typically deliver a cocktail of gases to a patient to ensure sedation during surgery. Nitrous oxide (also known as laughing gas) and other gases are mixed with oxygen and delivered to the patient. The buffer area shown in the drawing below is where the combination of nitrous oxide and oxygen is mixed together. Here, the anesthesiologist needs to be aware of the mix of gases that is appropriate to the patient. At times, the combination needs to be adjusted depending on patient requirements.

To control the level of oxygen and nitrous oxide delivered to the buffering section of the anesthesia machine, it is necessary to measure the volume of each gas. In the drawing below, the FS4008 mass flow sensor is shown as a method to measure and monitor the various gas levels. The FS4008 comes in various flow ranges from 0-10 SLPM up to 0-50 SLPM. Available outputs include linear voltage or digital RS232 or RS485, allowing for the FS4008 to be easily integrated into a control system for the various gases. The flow channel diameter is 8 mm, and there are exchangeable mechanical connectors for ease of installation (BSPT thread and one-touch connectors).Slide2.jpg


At the delivery location of the gas mixture to the patient, another flow measurement point is needed. Here, the FS6022 mass flow sensor can play an important role in ensuring gases are delivered to the patient and then subsequently exhaled. Because the FS6022 has bi-directional measurement capability, it is ideal for use in the scavenging portion of the anesthesia machine, which expels the used gas from the patient's lungs.  For details about the FS6022, you can also review our blog post: Mass Flow Sensors for Medical Ventilators

In summary, measuring and monitoring mass flow of gases in anesthesia equipment is a critical part of patient comfort and surgery success. Not only is it important to measure the mix of anesthesia gases, it is also vital to measure delivery of the gases to the patient.

You can learn more about mass flow sensors here or download our mass flow product & pricing guide.

Download Mass Flow  Product & Pricing Guide


Topics: Mass Flow Sensors

Mass Flow Sensors for Medical Ventilators

Posted by Seta Davidian on Feb 23, 2016 9:39:29 AM

A ventilator uses pressure to blow air or a mix of air and oxygen to a patient. This blog post describes how the FS1015FL (shown on the left below) and FS6022 (shown on the right below) mass flow sensors are used in medical ventilators. These mass flow sensors are members of the new Siargo line which Servoflo is now offering.

mass flow sensor fs1015clmass flow sensor bi-directional bidirectional fs6022 

Both of these mass flow sensors use a MEMs sensor chip based on the calorimetric principle. The chip is packaged in a special way to receive laminar flow. The sensor chip has a micro heater and a pair of sensors upstream and downstream. When gas flow passes over the sensor chip, it brings the heat from upstream to downstream. Mass flow rate is calculated by measuring the temperature differences from the upstream and downstream sensors.

The illustration below shows how the mass flow sensors are installed inside the ventilator. The inlet air and oxygen is mixed and delivered to the buffer and valve. The FS1015CL sensors are calibrated for either 0-100 SLM or 0-150 SLPM. The flow rate of air/oxygen is measured to ensure the correct amount is delivered to the patient. The FS1015 has a 5V supply with a linear voltage output or an I2C interface. Standard ISO 15 mm medical connection is available. 

mass flow sensors in medical ventilators


The FS6022 is a mass flow sensor with a bi-directional option. Ranges include up to 250 SLPM or 300 SLPM. Having a standard voltage output, the bi-directional model provides a 2.5 to 5V output for the positive full-scale flow rate and 2.5 to 0 V for the negative flow rate.  Here, the FS6022 is used to monitor the inhalation and exhalation of the patient. 

These sensors can be sterilized in medical liquids.


We have a recently updated mass flow sensor product & pricing guide which includes these models. 

Download Mass Flow  Product & Pricing Guide

Topics: Mass Flow Sensors