US 5,040,431 AGranted

Movement guiding mechanism

AssigneeCanon Kabushiki Kaisha

InventorsShigeo Sakino, Eiji Osanai, Mahito Negishi, Michio Horikoshi, Mitsuru Inoue, Kazuya Ono

Life of this patent

Estimating the term…

Loading patent…

Abstract

In a movement guiding device, two parallel stationary guides are fixed to a surface plate and plural hydrostatic gas or bearing members are provided for the surface plate and the stationary guides. A Y stage is moved in a Y-axis direction under the influence of these bearing members. Additional hydrostatic gas or air bearing members are provided in relation to the surface plate and the Y stage so as to support an X stage for movement in an X-axis direction orthogonal to the Y-axis direction. Guide of the Y stage in the X-axis direction is made by the stationary guides on the surface plate, while guide thereof in a Z-axis direction perpendicular to an X-Y plane is made by the surface plate. Guide of the X stage in the Y-axis direction is made by the Y stage, while the guide thereof in the Z-axis direction is made by the surface plate, similar to the Y stage. With such structure, any vibration, rolling, or otherwise, of the Y stage is not transmitted to the X stage. Thus, high-precision guide is attainable. Linear motors are used as drive sources for the X and Y stages, so that all movable portions are provided by non-contact structures. Further, suitable brake members are used, which members are operable at a time of an accident of the stage. By this, accidental collision of the stage and/or derailment of the stage from the guide can be prevented.

Claims12

Dependent claims

A movement guiding device, comprising:

a surface plate;
two stationary guides fixed on said surface plate;
a first movable member mounted on said surface plate in an internal space between said stationary guides;
a second movable member mounted on said surface plate so as to straddle said first movable member;
a first drive source for moving said first movable member in a first direction relative to said surface plate;
a second drive source for moving said second movable member, relative to said first movable member, in a second direction perpendicular to the first direction;
first bearing means comprising a first pad disposed between said first movable member and said surface plate and a second pad disposed between said first movable member and said stationary guides, said first bearing means further comprising means for discharging gas from each of said first and second pads for supporting said first movable member relative to said surface plate in a direction perpendicular to said surface plate, and for guiding said first movable member in the first direction relative to said stationary guides;
and
second bearing means comprising a third pad disposed between said second movable member and said surface plate and a fourth pad disposed between said second movable member and said first movable member, said second bearing means comprising means for discharging gas from each of said third and fourth pads for supporting said second movable member relative to said surface plate in the direction perpendicular to said surface plate and for guiding said second movable member in the second direction relative to said first movable member.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 07/299,340Filed 23 Jan 1989
Priority: JP 63-1213722 Jan 1988
Granted: 20 Aug 1991
Term ends: Not estimatedThe source records don’t support an estimate.

Classification13 codes

F16C 29/025
Sliding-contact bearings: hydrostatic or aerostatic
F16C 29/008
Bearings for parts moving only linearly: systems with a plurality of bearings, e.g. four carriages supporting a slide on two parallel rails
F16C 32/06
Bearings not otherwise provided for: with moving member supported by a fluid cushion formed, at least to a large extent, otherwise than by…
G03F 7/70716
Handling of masks or workpieces: stages