Limit Switch Security Features
Electronic tensile testing machine is also known as tensile machine, mainly used for metal and non-metallic materials stretching, compression, bending and other mechanical properties of testing machinery. Its structure principle is the use of mechatronics design, by the force sensor, transmitter, microprocessor, load-driven mechanism, limit switch, computer and color inkjet printers and other components. Today, the small series on the limit switch in the tensile testing machine application, for everyone to introduce the use of attention to some problems.
In the tensile testing machine main cylinder and the hydraulic Chuck Department, are equipped with protection overflow valve and limit switch. Among them, the limit switch device includes upper and lower two limit switch, which is responsible for the safety protection function of the tensile machine. Function of the general body now, two limit switches can be avoided by the pull machine misoperation, the device caused by the force sensor damage.
Before testing, it is necessary to check whether the safety limit switch of the rally machine is working. For electronic material testing machine, the upper limit of load should be set before test, so as to avoid the damage of force sensor caused by overload.
It is important to note that the operator must check the limit switch to see if it is firm and fastened before powering on the rally machine. The upper and lower level switches must be tuned to the appropriate position and are fastened. Among them, the location of the limit switch is generally to install a good fixture, so that the fixture will not collide as the basic principle. Otherwise, the sensor or fixture will be crashed, causing the test machine to be paralyzed and unable to work properly.
In addition, when the tensile test machine rises or drops to install the specimen, the operator should pay attention to control the space and running speed of the upper and lower fixture. Failure to do so will result in the damage of the fixture or the force sensor. In addition, in order not to allow the accuracy of the force sensor deviation too large, the operator should not allow some hard objects to collide with the force sensor.
The limit switch, also known as stroke switch, position switch, is a kind of common small current main electric appliance. By using the collision of the mechanical moving parts, the contact action is realized and the control circuit is connected or broken.
The limit switch is mainly composed of three parts, the actuator, the contact system and the shell. In practical application, the limit switch is usually installed in the predetermined position, when the mechanical bump or moving parts hit the limit switch, the internal contact action of the switch is realized and the circuit is switched.
Limit switch selection, the main consideration of action requirements, installation location and the number of contacts, the specific as follows:
(1) Select the type of limit switch according to the use situation and control object.
(2) Select the form of protection according to the installation environment.
(3) Select series according to the rated voltage and rated current of the control loop.
(4) Choose a reasonable actuator form according to the relation between the transfer force and displacement of the limit switch.