Multi-way reversing valve

[0024] Example one

[0025] Such as figure 2 As shown, a multi-way directional valve includes a three-position four-way electromagnetic directional valve unit 4, the oil inlet of the three-position four-way electromagnetic directional valve unit 4 communicates with the main oil inlet oil path, and the three-position four-way electromagnetic directional valve unit 4 The oil return port of the directional valve unit 4 communicates with the main oil return oil path. In the neutral state, the oil inlet of the three-position four-way solenoid directional valve unit 4 is disconnected from the working oil port. In this embodiment, the spool valve performance code of the working position function of the three-position four-way electromagnetic directional valve unit 4 is "Y".

[0026] The three-position four-way manual reversing valve unit 3 is connected in parallel with the three-position four-way electromagnetic reversing valve unit 4. The oil inlet of the three-position four-way manual reversing valve unit 3 is connected to the main oil inlet, and the three-position four-way manual The oil return port of the directional valve unit 3 communicates with the main oil return oil path. In the neutral state, the oil inlet of the three-position four-way manual reversing valve unit 3 is disconnected from the working oil port. In this embodiment, the spool valve performance code of the working position function of the three-position four-way manual reversing valve unit 3 is "Y".

[0027] A hydraulic control neutral unloading valve 2 is arranged between the main oil inlet oil circuit and the main oil return oil channel, and the hydraulic control neutral unloading valve 2 is a two-position two-way valve. The control oil port of the hydraulic control neutral unloading valve 2 is in communication with the working oil port of the three-position four-way electromagnetic reversing valve unit 4. A check valve 5 is arranged between the working oil port of the three-position four-way electromagnetic reversing valve unit 4 and the control oil port of the hydraulic control neutral unloading valve 2. The control oil port of the hydraulic control neutral unloading valve 2 is in communication with the working oil port of the three-position four-way manual reversing valve unit 3. A check valve 5 is provided between the working oil port of the three-position four-way manual reversing valve unit 3 and the control oil port of the hydraulic control neutral unloading valve 2. An overflow valve is provided between the oil inlet of the hydraulic control neutral unloading valve 2 and the main oil return path. A throttle valve 6 is provided between the control oil port of the hydraulic control neutral unloading valve 2 and the main oil return path.

[0028] The hydraulic control neutral unloading valve 2, the three-position four-way electromagnetic reversing valve unit 4, and the three-position four-way manual reversing valve unit 3 are all set in different monomers. Way reversing valve (such as image 3 (Shown), the cartridge structure can improve the versatility of the multi-way directional valve.

[0029] The working principle of this multi-way directional valve is:

[0030] When the three-position four-way solenoid directional valve unit 4 is in the neutral position, there is no load on the working oil ports A2, B2 and T port, the one-way valve 5 does not operate, and the hydraulic control neutral unloading valve 2 has no load sensing area. pressure. When the pressure generated by the pressure oil at the oil inlet P on the spool of the hydraulic control neutral unloading valve 2 exceeds the setting value of the hydraulic control neutral unloading valve 2 spring, it will push the hydraulic control neutral unloading valve 2 valve The rod moves to the right, the spring is compressed, the P port is connected to the T port through the hydraulic control neutral unloading valve 2, the pressure oil is unloaded and the oil is returned, and the overflow valve plays a protective role.

[0031] When the valve stem of the three-position four-way solenoid valve unit 4 moves to the left, the P port hydraulic oil enters the A2 port, and the B2 port communicates with the T port. When the pressure at port A2 exceeds the set value, open the one-way valve 5 and communicate with the spring chamber of the one-way valve 5 and the hydraulic control neutral unloading valve 2. At this time, the hydraulic oil in the left cavity of the hydraulic control neutral unloading valve 2 is opposite to the valve The force of the core is less than the sum of the hydraulic oil in the spring cavity of the hydraulic control neutral unloading valve 2 and the force of the spring on the spool, so the hydraulic control neutral unloading valve 2 valve stem moves to the left, and the hydraulic control neutral position The oil circuit of the unloading valve 2 is disconnected. The pressure oil controls the actuator after passing through the three-position four-way electromagnetic reversing valve unit 4. When the valve stem of the three-position four-way electromagnetic reversing valve unit 4 moves to the right, the principle is the same as when the valve stem of the three-position four-way electromagnetic reversing valve unit 4 moves to the left, and will not be repeated here.

[0032] The working principle of the three-position four-way manual reversing valve unit 3 is similar to the working principle of the three-position four-way electromagnetic reversing valve unit 4, and will not be repeated here.

[0033] Example two

[0034] The structure of the second embodiment is basically the same as that of the first embodiment. The difference is that a shuttle valve 7 is provided between the working oil port of the three-position four-way electromagnetic reversing valve unit 4 and the control oil port of the hydraulic control neutral unloading valve 2. A shuttle valve 7 is provided between the working oil port of the three-position four-way manual reversing valve unit 3 and the control oil port of the hydraulic control neutral unloading valve 2, such as Figure 4 Shown.

[0035] The multi-way reversing valve of the first embodiment and the second embodiment can be used in, but not limited to, harvesting machinery such as corn harvesters. Among them, the oil cylinder of the ear picking table is controlled by the three-position four-way electromagnetic reversing valve unit 4.