Processing apparatus and processing method

A processing apparatus that forms a half member of an acceleration cavity portion by processing a hollow object-to-be-cut, one end of which serves as a large-diameter portion and the other end of which serves as a small-diameter portion, the processing apparatus comprising:

• a securing jig having a curved outer surface that secures the object-to-be-cut by sucking an inner surface of the object-to-be-cut, which is an opposite surface of a portion-to-be-cut, so that the portion-to-be-cut of the object-to-be-cut is exposed;
• a rotational drive portion that rotates the securing jig;
• and
• a cutting tool that cuts the object-to-be-cut,
• wherein, on the outer surface, two O-rings are provided, one of which is provided at a portion which comes into contact with the large-diameter portion and the other of which is provided at a portion which comes into contact with the small-diameter portion, and an opening portion that sucks the object-to-be-cut is formed between the two O-rings.

A processing method employing a processing apparatus that forms an acceleration cavity member by processing a hollow object-to-be-cut, one end of which serves as a large-diameter portion and the other end of which serves as a small-diameter portion, the processing method comprising:

• a step of securing the object-to-be-cut with a securing jig formed of a plurality of members;
• a step of rotating the securing jig with a rotational drive portion;
• and
• a step of cutting the object-to-be-cut with a cutting tool,
• wherein the step of securing the object-to-be-cut includes:
• a step of, when cutting a first portion-to-be-cut of the object-to-be-cut, combining the plurality of members in a first pattern so that the first portion-to-be-cut is exposed, and
• a step of, when cutting a second portion-to-be-cut of the object-to-be-cut, combining the plurality of members in a second pattern, which is different from the first pattern, so that the second portion-to-be-cut is exposed, and
• wherein the combination of the plurality of members is changed from the first pattern to the second pattern without removing the object-to-be-cut from the securing jig.

A processing method employing a processing apparatus that forms a half member of an acceleration cavity portion by processing a hollow object-to-be-cut, one end of which serves as a large-diameter portion and the other end of which serves as a small-diameter portion, the processing method comprising:

• a step of securing the object-to-be-cut with a securing jig by bringing a curved outer surface of the securing jig, which comes into contact with the object-to-be-cut, into contact with an inner surface of the object-to-be-cut, which is an opposite surface of a portion-to-be-cut so that the portion-to-be-cut of the object-to-be-cut is exposed;
• a step of rotating the securing jig with a rotational drive portion;
• a step of cutting the object-to-be-cut with a cutting tool and
• a step of providing, on the outer surface, two O-rings, one of which is provided at a portion which comes into contact with the large-diameter portion and the other of which is provided at a portion which comes into contact with the small-diameter portion,
• wherein the step of securing the object-to-be-cut secures the object-to-be-cut by sucking the inner surface of the object-to-be-cut by means of an opening portion formed between the two O-rings on the outer surface.