Length measurement technology with SIKO draw-wire encoders
Draw-wire encoders, also known as draw-wire sensors or wire-actuated encoders, have been an authority in the field of length measurement technology for many years and have already proven themselves in a variety of operating conditions, including very difficult ones. Robust, compact design with maximum precision and reliability are the criteria that are set as the most important goals for every new development in this area.
Only a draw-wire encoder can be used as a linear displacement transducer in many applications, since it is often not possible to use guided sensor systems for measurement.
Draw-wire encoders are flexible in terms of integration and interfaces
The simple installation and guidance of a draw-wire encoder enables simple and flexible integration of a measuring system into existing systems. Different interfaces and output signals enable connection to a wide range of control concepts
Draw-wire sensors are robust, even under adverse conditions
Draw-wire sensors provide a wide range of possible applications thanks to the possibility of attaching different encoders, regardless of which signal output is required. The user is able to install the encoder himself using simple means. Even outdoor use, which can never be ruled out, especially with mobile machines, is already a standard feature of the draw-wire displacement transducers: working temperature range from -40° C to +80° C, robust housing and even drainage openings for draining liquids from the device.
Basic structure of SIKO draw-wire sensors
The mode of operation is very simple: a measuring cable is wound in a single layer on an internal drum, which guarantees very high linearity over the entire measuring range. Pulling out the cable causes the drum to rotate. The angle sensor, which is directly connected to the drum axis, registers this rotation and generates a measurement signal proportional to the cable movement that can be used as required. A spiral spring on the drum's axis of rotation returns the cable. Because the cable is simply attached to the measurement object, very little installation effort is required.
Pulleys enable indirect measuring paths
This eliminates the need for additional guide systems or the installation of energy supply chains. The flexible cable also enables linear position measurements in inaccessible places. Indirect measuring paths can also be realized with the aid of deflection pulleys.
Wide range of measuring lengths
From compact miniature designs with a measuring length of 600 mm to solutions with cable extension lengths of 15 m, these draw-wire encoders cover almost the entire range of industrial applications.
Wide range of applications
SIKO draw-wire encoders have been used successfully in various industries since the 1990s. Examples of applications include position monitoring of operating tables and treatment chairs in medical technology and use as robust sensors in mobile automation. They are used, for example, to monitor the outriggers of mobile cranes in crane and lifting technology.
Plus points
- Temperature range down to -40° C
- Robust in use even when wet and dirty
- Simple installation of the cable extension
- Flexible system integration of any output signals and interfaces
- Optionally increased safety thanks to redundant sensors (safety variants)