Mobile hand-held or back-carried small engines must be weight-optimized due to their operability. At the same time there is enormous cost pressure within this market segment. Therefore, not all comfort and additional functions to increase user-friendliness can be adopted from the stationary applications. These include, for example, electric starting devices or additional sensors and actuators that take over advanced control processes to prevent or detect and report user or system errors.
In the mobile small engine segment, this situation leads to the problem that the systems have many requirements for the user. These include, for example:
physical ability to operate a pull starter
know-how about the functioning of a combustion engine (2-stroke and 4-stroke)
know-how for detecting failures and remedial actions
If the knowledge about the behavior of engines is not given, or failures are overlooked, this automatically leads to a form of physical strain on the user due to the many unsuccessful start attempts, which can lead to further subsequent errors.
In the home and hobby segment this leads to a certain frustration and customer dissatisfaction, so that every engine or equipment manufacturer and ignition system supplier pays special attention to and optimizes the starting and running behavior of the application during product development.
In the area of critical applications there are tougher requirements for the reliability and operability, where the above-mentioned conditions can lead to catastrophic consequences with injuries, personal or environmental damage.
This article describes a possibility to extend a mobile, back-carried 2-stroke engine, which is used as a wildfire water pump by fire brigades (Figure 1) with an additional user interface to minimize the demands on the user and to ensure immediate feedback in case of a failure, so that measures can be initiated as quickly as possible without the need for extensive troubleshooting.