JP2013130260A5 - Liquid guide device - Google Patents

Description

The present invention relates to a liquid guide device including a liquid hydrostatic bearing, which is used in, for example, an ultraprecision machine.

As the linear guide apparatus, a liquid guide device provided with a liquid hydrostatic bearing (liquid electrostatic圧直dynamic guiding apparatus) is known. The hydrostatic bearing forms a lubricating fluid film by forcibly supplying a pressurized fluid to the bearing gap between the bearing surface of the movable body and the guide surface of the guide member, and the pressure of the lubricating fluid film This is a bearing that floats a movable body in a non-contact manner. In a liquid hydrostatic bearing that uses a liquid as a working fluid, in many cases, as shown in FIG. 8 (a), the movable body 2 is formed with a recess 4 that opens to the bearing surface 3 (oblique lattice region). . In addition, as shown in FIG.8 (b), the part remove | excluding the opening surface 5 (satin surface area | region) of the recessed part 4 from the bearing surface 3 is called the land 6 (lattice area | region). Therefore, the bearing surface 3 is composed of the opening surface 5 of the recess 4 and the land 6.

The present invention has a guide member having a guide surface and a bearing surface that constitutes a hydrostatic bearing between the guide surface and is arranged in a state where a pressurized pressure is applied toward the guide surface, a movable body that moves along the guide member, the liquid guide apparatus having a liquid supply means for supplying a liquid, the between the bearing surface and the guide surface, said the movable body, the bearing surface is moved It is arranged plurality in the direction, wherein the plurality of bearing surfaces, respectively, from the guide surface to the liquid supply hole which is disposed in a recess that opens toward, liquid is supplied by the liquid supply means, the center of gravity of said movable member In the recess in front of the moving direction, the liquid supply hole is formed in the moving direction forward of the center of the recess, and in the recess in the moving direction rearward of the center of gravity of the movable body, the recess How to move than the center of Sometimes the liquid guiding device, characterized in that the liquid supply hole to the rear is formed.

<First Embodiment>
A first embodiment of the present invention will be described with reference to FIGS. First, a schematic configuration of the liquid guide device will be described with reference to FIG.

[ Liquid guide device ]
As shown in FIG. 1A , the liquid guide device of the present embodiment (hereinafter referred to as a liquid static pressure linear motion guide device ) includes a guide member 1a, a movable body 2, and a pressurized liquid that is a liquid supply means. And a supply device 9. The guide member 1a is a rail-shaped member, for example, and has a guide surface 1 parallel to the moving direction of the movable body 2 on one side. The movable body 2 is, for example, a stage on which a workpiece of an ultra-precision processing machine is placed, and is movable along the guide member 1a in the arrow direction (left-right direction) in FIG. Is arranged. Examples of the driving mechanism include a ball screw mechanism. That is, a male screw is arranged in parallel with the guide member 1a, and this male screw is screwed into a female screw portion provided on the movable body 2 via a ball. And by driving a motor and rotating a male screw, the movable body 2 moves along a male screw based on the screwing of a male screw and a female screw part.

The pressurized liquid supply device 9 supplies a liquid having a constant pressure between the bearing surface 3 and the guide surface 1 with, for example, a pump. In the case of this embodiment, liquid (pressurized fluid) is supplied between the bearing surface 3 and the guide surface 1 from the pressurized liquid supply device 9 via the fluid path 9 a of the movable body 2. Further, a throttle (not shown) is provided upstream of the fluid path 9a so that the pressure of the pressurized liquid sent from the pressurized liquid supply device 9 is once lowered and then sent to the fluid path 9a.

In the present embodiment, the plurality of liquid supply holes 7 are arranged so that the liquid supply point P satisfies the following conditions. That is, the sum of the distances in the movement direction between the liquid supply point P in each recess and the center of gravity G of the movable body 2 is the distance in the direction of movement between the center N of the recess and the center of gravity G of the movable body 2. Each liquid supply hole 7 is arranged so as to be larger than the total sum. In the case of this embodiment, a plurality of bearing surfaces 3, a plurality of recesses 4, and a plurality of liquid supply holes 7 are perpendicular to the moving direction of the movable body 2 and pass through the center of gravity G of the movable body 2. They are arranged symmetrically against the.

In terms of the positional relationship in FIG. 1A, the liquid supply point P is located on the left side of the center N of the concave portion 4 in the concave portion 4 of the liquid hydrostatic bearing located on the left side of the center of gravity G of the movable body 2. On the other hand, in the concave portion 4 of the liquid hydrostatic bearing on the right side of the center of gravity G of the movable body 2, the liquid supply point P is located on the right side of the center N of the concave portion 4. That is, the liquid supply hole 7 is formed ahead of the center N of the recessed portion 4 in the moving direction in the recessed portion 4 ahead of the center of gravity G of the movable body 2. On the other hand, in the recess located behind the center of gravity G of the movable body 2 in the movement direction, the liquid supply hole 7 is formed behind the center N of the depression 4 in the movement direction.

Claims (8)

A guide member having a guide surface;
A movable body that has a bearing surface that constitutes a hydrostatic bearing with the guide surface, is arranged in a state where a pressurized pressure is applied toward the guide surface, and moves along the guide member;
In a liquid guide device comprising: a liquid supply means for supplying a liquid between the bearing surface and the guide surface;
Wherein the movable body, the bearing surface is arranged more to the direction of movement,
A liquid is supplied to the plurality of bearing surfaces by the liquid supply means from a liquid supply hole disposed in a recess opening toward the guide surface ,
The liquid supply hole is formed in the moving direction forward of the recess in the moving direction ahead of the center of gravity of the movable body,
The liquid supply hole is formed at the rear in the moving direction from the center of the concave portion in the concave portion at the rear in the moving direction from the center of gravity of the movable body.
A liquid guide device characterized by that. The liquid supply hole has a total sum of distances in the moving direction between a liquid supply point serving as a geometric center of gravity of the liquid supply hole in each recess and a center of gravity of the movable body, and the center of the recess. It is arranged to be larger than the sum of the distances in the respective moving directions with the center of gravity of the movable body,
The liquid guide apparatus according to claim 1, wherein A guide member having a guide surface;
A movable body that has a bearing surface that constitutes a hydrostatic bearing with the guide surface, is arranged in a state where a pressurized pressure is applied toward the guide surface, and moves along the guide member;
In a liquid static pressure linear motion guide device comprising: a liquid supply means for supplying a liquid between the bearing surface and the guide surface;
A plurality of the bearing surfaces are arranged in the moving direction on the movable body,
The plurality of bearing surfaces are each formed with a recess that opens toward the guide surface, and a liquid supply hole that is disposed on the bottom surface or wall surface of the recess and is supplied with liquid from the liquid supply means.
The liquid supply hole has a total sum of distances in the moving direction between a liquid supply point serving as a geometric center of gravity of the liquid supply hole in each recess and a center of gravity of the movable body, and the center of the recess. It is arranged to be larger than the sum of the distances in the respective moving directions with the center of gravity of the movable body,
A liquid guide device characterized by that. The plurality of liquid supply points are arranged symmetrically with respect to a virtual plane that is perpendicular to the moving direction of the movable body and passes through the center of gravity of the movable body.
The liquid guide device according to claim 2, wherein the liquid guide device is a liquid guide device. The liquid supply means supplies the pressurized fluid supplied from the pressurized fluid supply device to the liquid supply hole via a fluid path.
The liquid guide apparatus according to claim 1, wherein the liquid guide apparatus is a liquid guide apparatus. The liquid supply hole is formed in the bottom surface of the recess.
The liquid guide device according to claim 1, wherein the liquid guide device is a liquid guide device. The liquid supply hole is formed in the wall surface of the recess.
The liquid guide apparatus according to claim 1, wherein the liquid guide apparatus is a liquid guide apparatus. The shape of the opening surface of the concave portion is either a square, a rectangle, a circle or an ellipse.
The liquid guide device according to claim 1, wherein the liquid guide device is a liquid guide device.