Vacuum pump
There is obtained a vacuum pump which suppresses an influence on external piping caused by a contact failure of a rotor during rotation of the rotor. A temperature rise ring 301 is provided in the vacuum pump, an outlet port 133 to which the external piping is connected is connected to the temperature rise ring 301 , and a rotational force is directly or indirectly applied to the temperature rise ring 301 due to the contact failure of the rotor during the rotation of the rotor. In addition, a rotation suppression means (a hole 301 a and a bolt 305 ) for suppressing rotation of the temperature rise ring 301 by the above-described rotational force is provided separately from a connection portion between the temperature rise ring 301 and a casing (outer tube 127 a ).
1 . A vacuum pump comprising:
a rotor;
a stator;
a casing which houses the rotor and the stator, the casing including a first hole;
a base portion disposed at a bottom portion of the casing;
an annular member to which a rotational force of the rotor is directly or indirectly applied when the rotor contacts the annular member during rotation of the rotor, the annular member including a second hole;
a piping connection portion which is connected to the annular member and to which external piping is connected;
a fixing bolt provided along an axial direction of the vacuum pump and for fixing the casing and the annular member; and
a rotation suppression means including a rotation suppression bolt disposed in the second hole, the rotation suppression means being for suppressing rotation of the annular member by the rotational force separately from a connection portion between the annular member and the casing, wherein:
the annular member is not fixed directly to the base portion,
the rotation suppression bolt disposed in the second hole is provided along a radial direction of the vacuum pump,
the rotation suppression bolt is fixed to the first hole by screw connection,
when the rotor contacts the annular member, the rotation suppression bolt disposed in the second hole contacts with an inner surface of the second hole, and
when the rotor does not contact the annular member, a gap is provided between the rotation suppression bolt disposed in the second hole and the inner surface of the second hole.
2 . The vacuum pump according to claim 1 , wherein:
the rotation suppression means includes a rotation regulation portion which is formed in the annular member and a rotation regulation member which is fixed to the casing and comes into contact with the rotation regulation portion by the rotational force.
3 . The vacuum pump according to claim 2 , wherein:
the annular member is a temperature rise ring which raises a temperature of a gas flow path by heat generation of a heater.
4 . A vacuum pump comprising:
a rotor;
a stator;
a casing which houses the rotor and the stator;
an annular member to which a rotational force of the rotor is directly or indirectly applied when the rotor contacts the annular member during rotation of the rotor;
a piping connection portion which is connected to the annular member and to which external piping is connected;
a rotation suppression means for suppressing rotation of the annular member by the rotational force separately from a connection portion between the annular member and the casing; and
a base portion disposed at a bottom portion of the casing, the base portion including a first hole, wherein:
the rotation suppression means includes a rotation regulation portion which is formed in the annular member and a rotation regulation member which protrudes in an axial direction from the base portion and comes into contact with the rotation regulation portion by the rotational force,
the annular member includes a flange and a second hole or a notch formed in the flange,
the rotation regulation portion is the second hole or the notch,
the rotation regulation member is a bolt fixed to the first hole of the base portion by screw connection along the axial direction,
when rotor contacts the annular member, a portion of the bolt protruding from the base portion contacts with an inner surface of the second hole or the notch of the flange, and
when the rotor does not contact the annular member, a gap is provided between the portion of the bolt protruding from the base portion and inner surface of the second hole or the notch of the flange.
5 . The vacuum pump according to claim 1 , wherein:
the annular member is a temperature rise ring which raises a temperature of a gas flow path by heat generation of a heater.
6 . The vacuum pump according to claim 1 , wherein
the piping connection portion is an outlet port.
7 . The vacuum pump according to claim 1 , wherein the gap is a first gap, and wherein:
the annular member is spaced from the base portion such that a second gap is formed between the annular member and the base portion, and
the second gap is provided with a sealing.