the utility model relates to a pressure regulating valve for preventing O-ring bursting

Comprising a pump head, the pump head is installed with a thimble seat, the thimble seat is provided with a top pinhole, the top pinhole is provided with a thimble jacket with an O-ring, which is characterized in that the thimble jacket is provided with a stop ring under the O-ring. In this scheme, the thimble jacket located under the O-ring has a stop ring. With the stop ring, the friction caused by the thimble moving up and down is borne by the stop ring, which not only eliminates the damage to the extrusion seal ring caused by the large gap between the thimble and the top pin hole of the pump head and the thimble seat, but also ensures the flexibility of the thimble moving up and down. Effectively solve the leakage problem caused by the O-ring being broken, and the inconvenience caused by frequent replacement of the O-ring, easy to install.