As an inseparable part of the control system of construction machinery and an indispensable part of the human-machine interface, industrial handles are now widely used in many fields and branches of domestic construction machinery, agricultural machinery, aerial work platforms, etc.
At present, in industrial use, according to the major classification of control forms, there are roughly three types of industrial joysticks: 1. Mechanical joystick; 2. Hydrauli joystick;3. Electric control joystick.
Among them, in most industries, mechanical handles have been gradually eliminated in the process of industrial upgrading in my country due to their inability to complete complex analog actions and logic control, and are only used in some low-cost occasions with high cost requirements.
The hydraulic handle, or the industry collectively referred to as the hydraulic pilot handle, is currently the mainstream application in the market. Its advantage is that it can use lower costs to control the flow of the hydraulic pilot valve and cooperate with the controller for basic logic control. In addition, the pilot Because the handle does not involve electrical performance and other faults, its maintenance and replacement are also more convenient, but there are also occasions where the hydraulic handle cannot avoid oil leakage, and it cannot be used in some occasions with higher operating environment requirements.
Finally, there is the electronic control handle, which has stable electrical signal, strong editability, and can handle complex operation logic. The tendency of the system to switch to an electronically controlled system. The advantage of the electronic control system is that it can do more complex logic systems and safety systems. It has been used for decades in the aerial work vehicle industry with high safety factor requirements. And the electronic control handle system can be used in many industries that require high environmental cleanliness, such as supermarket storage, video surveillance, medical treatment, etc.
Generally speaking, the operation method is determined according to the operating conditions and operating habits. On the other selection issues, the most questionable is the choice of Hall type and potentiometer type.
Hall type is characterized by active, non-contact operation, and the life can be made longer. Usually the potentiometer type has a lifespan of 1 million times to 2 million times, and the hall type can achieve 5 million times or even higher; but it needs power supply to complete the analog output, and the hall type handle cannot be used in The environmental pollution is serious, especially in the environment with a lot of metal dust or strong external magnetic field, the change of the magnetic field will make the output of the handle change or even fail.
The potentiometer type is characterized by passive, contact-type operation, and its stability relative to the Hall will be better. Generally speaking, the life of the potentiometer is related to the life of the potentiometer itself. Most domestic high-quality potentiometers have a lifespan of hundreds of thousands to millions of times, and some imported potentiometers can reach 1 million to 2 million times or even more. high. During the use of the potentiometer type, no additional power supply is required.
According to the above characteristics, the electronic control handle usually used for excavators, loaders and other high frequency use is generally of the Hall type. It is used for mining machinery and other situations where there may be metal dust or electromagnetic interference. It is recommended to use a potentiometer. Type of electronic control handle. In addition, it is also determined according to whether there is an additional power supply on the client system side. Usually, the conventional voltage of Hall is 3.3Vdc and 5Vdc, and the wide voltage version can be powered by 9~36Vdc.
In addition, there is a bus-type output form, which is generally used in occasions where bus communication is required. In general, the construction machinery industry uses more CAN bus types. Other industries also use RS232, RS485, USB and other bus output forms. Customers need to choose according to their own working conditions.
Finally, there are the applications of spring return type and friction positioning type:
1. Spring return type: when the operating frequency is high and it needs to be reset to the neutral or starting position. Usually, construction machinery, aerial work vehicles, forklifts and other occasions require frequent operation or reset function.
1. Friction positioning type: the occasions where the operation frequency is low and it is necessary to operate to the positioning position. It is usually used for agricultural machinery, drilling rigs, mining and other machinery that need to keep the operating voltage running continuously.
