Electronic expansion valve

Abstract

The invention discloses an electronic expansion valve. The electronic expansion valve comprises a valve seat, a valve needle, an external threaded shaft, a connecting piece and a compression spring, wherein the compression spring is installed outside the connecting piece; both ends of the connecting piece are respectively connected with the external threaded shaft and the valve needle, and the compression spring is located between the external threaded shaft and the valve needle and is configured, so that the connecting piece can be driven to move in an axial direction by the external threadedshaft, the external threaded shaft and the valve needle can relatively move in the axial direction, when a valve port is in the early stage of the full-closed state, spring force which is used for pushing the valve needle to the valve port cannot be generated by the compression spring, and when the valve port is in the late stage of the full-closed state, elastic load which is used for closing the valve is generated on the valve needle by the compression spring; the early stage is from the beginning of closing the valve port by the valve needle until the external threaded shaft moves for a preset value in the valve closing direction relative to the valve needle; and the late stage is that the external threaded shaft moves for more than the preset value in the valve closing direction relative to the valve needle. According to the electronic expansion valve, the wear of the valve needle and the valve port can be reduced, so that the valve port is prevented from leaking when the valve port is fully closed.

Description

technical field [0001] The invention relates to the technical field of flow regulating valves, in particular to an electronic expansion valve. Background technique [0002] As an important part of the refrigeration system, the electronic expansion valve is widely used in large-scale refrigeration units, large-scale cold storage, supermarket freezers, etc. [0003] Please refer to Figure 1-2 , figure 1 It is a structural schematic diagram of a typical electronic expansion valve in the prior art; figure 2 for figure 1 Partial enlarged view of the middle I site. [0004] As shown in the figure, in the existing electronic expansion valve, the rotor 1' of the motor drives the externally threaded shaft 2', and the externally threaded part of the externally threaded shaft 2' is connected to the internally threaded part 3' fixed on the valve seat 4'. The threaded hole is threaded, and through the threaded engagement, the external threaded shaft 2' can move along the axis dir...

AI Technical Summary

Problems solved by technology

[0008] Since the valve needle 6' is located at the valve port 51' until the valve needle 6' is fully pushed to the valve port 51', the contact position between the valve needle 6' and the valve port 51' will always slide and rotate. , causing the contact surfaces of the two to be worn, especially in the case of repeated movements of the valve needle 6', the wear of the contact surface between the valve needle 6' and the valve port 51' will be further aggravated, causing the valve port 51' to be fully closed. The phenomenon of leakage under the state, resulting in poor valve performance

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