Edwards Japan Limited

Nahoko Yoshihara

Yoshiyuki Sakaguchi

Tooru Miwata

Kengo Saegusa

Yohei Ogawa

Yoshinobu Ohtachi

A main-body casing having an inlet port or an outlet port, a rotatable rotor shaft, and a rotor coupled to the rotor shaft are provided. A recess portion opened toward the inlet port is formed in the rotor and a fastening portion (a first shaft portion and a second shaft portion) of the rotor shaft is exposed to the recess portion. A cover portion, which is fastened to the fastening portion by a cover-portion fixing bolt and covers at least a part of the recess portion, is formed having a container shape and has a reinforcing portion located in a periphery of the fastening portion that prevents deflection by increasing rigidity. The cover portion also has a contact-pressure generating portion which is pressed by fastening to the fastening portion in a fastening direction and causes a contact pressure to be generated in the fastening direction.

Vacuum pump and vacuum pump component

To provide a vacuum pump which separates and constructs an inlet port flange and a casing (outer cylinder) as two components to reduce weight while retaining required strength and which is consequently capable of reducing manufacturing cost. In a vacuum pump, an inlet port flange and a casing (outer cylinder) are separated from each other and constructed as different members. The inlet port flange uses stainless steel as a material thereof and the casing (outer cylinder) use aluminum as a material thereof. The components are fastened to each other by bolts and sealed by an O-ring in order to maintain a vacuum property during assembly of the vacuum pump. Accordingly, a weight of the vacuum pump can be reduced while maintaining strength of the inlet port flange.

Vacuum pump, casing, and inlet port flange

A vacuum pump which can prevent lowering of an exhaust performance of the vacuum pump, even if a linked-type thread groove spacer is fastened by a fixing bolt, is provided. The linked-type thread groove spacer according to an embodiment of the present invention includes a structure for linking a Siegbahn pump portion and a thread-groove pump portion. When this linked-type thread groove spacer is to be fastened, a countersunk hole is provided in advance in an exhaust channel portion, and the linked-type thread groove spacer is fastened to a base by a fixing bolt. As a result, a head part of the fixing bolt does not protrude to the exhaust channel, and the head part of the fixing bolt does not make resistance against an exhaust gas. Thus, lowering of the exhaust performance of the vacuum pump can be suppressed.

Vacuum pump and linked-type thread groove spacer

A vacuum pump reduces a stress without reducing the rotation speed of a rotating cylindrical body. In an outlet port-side lower portion of a rotor cylindrical portion included in the vacuum pump, a smaller diameter portion having an outer diameter smaller than that of an inlet port-side portion of the rotor cylindrical portion is provided. A lowermost end portion (outlet port-side end portion) of the rotor cylindrical portion is designed longer than a thread groove exhaust element to provide an extending portion. In the extending portion, a smaller diameter portion having an outer diameter smaller than that of the inlet port-side portion of the rotor cylindrical portion which is opposed to the thread groove exhaust element is provided.

Vacuum pump and rotating cylindrical body included in vacuum pump

A thread groove pump portion, which is an exhaust element, is structured such that a Siegbahn structure is attached onto a cylindrical thread, and such that respective parts are connected to each other at this attachment section. A flow channel of the Siegbahn portion and a flow channel of the cylindrical thread (the thread groove pump portion) are connected to each other so as to substantially form a right angle when viewed from an axis direction of the vacuum pump, thus, the flow channel of the Siegbahn portion and the flow channel of the thread groove pump portion are connected to each other. the length of a compression flow channel of the thread groove pump portion can be increased in a radial direction due to the connected Siegbahn portion.

Growing community of inventors

Chiba, Japan

Nahoko Yoshihara