Please explain the characteristics and application of centering function of O-type, M-type, H-type and P-type three-position four-way directional valves.

When the reversing valve is in the middle position, the O-type has four stations, all of which are blocked; M type is p, t, a, b; Type h is p, a, b and t; According to different classification standards such as purpose, function, number of oil port channels controlled, working position, control mode, valve core category, etc. Directional control valves can be classified in different ways.

When working, the drive shaft is driven by the drive transmission mechanism outside the valve, and the valve plate is started by the rocker arm, so that the working fluid sometimes leads from the left inlet to the lower outlet of the valve, and sometimes changes from the right inlet to the lower outlet, thus achieving the purpose of periodically changing the flow direction.

Extended data:

Three-position four-way electromagnetic directional valve is a new product developed for G series forklift trucks, which has obtained national patent. It is an essential component for electro-hydraulic reversing of various forklifts. In order to ensure the quality, the ex-factory test standard of solenoid valve is completely in accordance with international standards: it meets the performance requirements under the harsh conditions of oil temperature 130 degrees and rated voltage negative 15%.

The three-position four-way reversing valve consists of a two-position four-way reversing valve and a rest position. The three-position four-way reversing valve has many intermediate functions. The oil inlet p is connected with the working port b, and the working port a is connected with the oil return port t. The three-position four-way reversing valve can be a slide valve structure or an on-off valve structure.

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