Fuel oil supply nozzle method for manufacturing discharge pipe thereof

Abstract

A fuel oil supply nozzle includes a cylindrical discharge pipe and an anchor spring mounted on an outer circumference surface of the discharge pipe. The anchor spring is a spring wire in a spiral shape in a state in which a contact portion having a width and formed on one side in the direction of an axis is situated inside, and is mounted on the discharge pipe in a state in which the contact portion is pit into close contact with the outer circumference surface of the discharge pipe by a contracting force reducing the inside diameter of the spring.

1 . A fuel oil supply nozzle comprising:
 a nozzle body that has an inflow port formed on one end side, the inflow port being connected to an end portion of a fuel oil supply hose via which fuel oil is supplied, has an outflow port formed on the other end side, and has a valve mechanism for flowing the fuel oil, the valve mechanism being disposed in a flow passage formed between the inflow port and the outflow port;   a cylindrical discharge pipe having one end side connected to the outflow port of the nozzle body; and   an anchor spring to be mounted on an outer circumference surface of the discharge pipe,   wherein the anchor spring is formed using a spring wire into a spiral shape in a state in which a contact portion having a width and formed on one side in the direction of the axis of the spiral wire is situated inside, and is mounted in a state in which the contact portion is put into close contact with the outer circumference surface of the discharge pipe by a contracting force reducing the inside diameter of the spring.   
   
   
       2 . The fuel oil supply nozzle according to  claim 1 , wherein the contact portion of the anchor spring is formed with a concave surface and has both end sides of its width with protrusions pressed onto the outer circumference surface of the discharge pipe. 
   
   
       3 . The fuel oil supply nozzle according to  claim 1 , wherein the contact portion of the anchor spring is formed with a flat surface pressed onto the surface of the discharge pipe. 
   
   
       4 . A method for manufacturing a discharge pipe for a fuel oil supply nozzle, the method comprising the steps of:
 forming an anchor spring by winding a spring wire into a spiral shape in a state in which a contact portion having a width and formed on one side in the direction of the axis of the spiral wire is situated inside;   expanding an inside diameter on the contact portion side against a contracting force of the anchor spring;   inserting a straight discharge pipe into an inside diameter side of the expanded anchor spring and thereafter releasing the contracting force to press and mount the anchor spring on an outer circumference surface of the discharge pipe; and   bending the discharge pipe mounted with the anchor spring.   
   
   
       5 . The method for manufacturing a discharge pipe for a fuel oil supply nozzle according to  claim 4 , wherein the step of expanding the inside diameter of the anchor spring comprises fixing one end side of the anchor spring and rotating the other end side against the contracting force of the spring.