JPS585523A - Static pressure fluid slide apparatus - Google Patents

Abstract

PURPOSE:To prevent foreign matter from entering into a slide portion from the outside by providing a groove on the outside of a third oil duct having means for sucking fluid which is adapted to reclaim fluid, the groove being supplied with air. CONSTITUTION:A second oil duct 18 mounted on the outside of a pocket 15 of a fluid bearing is adapted to return most of operating oil to a hydraulic unit 23. The operating oil which is leaked out in a third oil duct 19 disposed on the outside of the second oil duct is compulsorily returned to the unit by a pump 30. Thus, the operating oil is prevented from leaking out of a slide apparatus. A groove 20 positioned outside of the third oil duct 19 is supplied with clean air from the outside, so that even if the third oil duct 19 is subjected to negative pressure by suction of the pump 30, foreign matter is prevented from entering between a guide 13 and a slide block 14.

Description

[Detailed Description of the Invention] The present invention relates to a slide device using a hydrostatic fluid bearing metal, and in particular provides a slide device that does not leak hydraulic oil, 2. and is compact in its entirety. .

Conventional slide mechanisms using hydrostatic fluid bearings have the following advantages, and have been used in many devices in recent years.

i　Frictional resistance of the sliding part is small.

11　Long life with no wear on the sliding part.

111 Bearing rigidity is greater than balls or rollers.

1v Due to the average effect of the fluid, straightness with higher accuracy than the processing accuracy of the guide can be obtained.

Although hydrostatic fluid bearings have excellent fLk points as described above, they have the disadvantage that when used in slide mechanisms, hydraulic oil tends to leak, and it is difficult to handle when used in devices. For this reason, it has been difficult to use hydrostatic fluid bearings in -C for relatively small dimensions.

The conventional example will be fully explained below with reference to FIGS. 1 to 6. 1 to 3 show a general slide mechanism, in which a slide block 2 slides along a guide 1. FIG. 4 is a circuit diagram of the hydraulic unit 3 part 3 for supplying all the hydraulic oil to the hydrostatic fluid bearing.

A slide block 2 slidably fitted into the guide 1 has a groove 4 on its inner surface, and hydraulic pressure is supplied from a first oil passage 5 through a throttle 6. Arrow P indicates the supply of hydraulic pressure, and arrow T indicates return to the tank 12. There is a second oil pipe 7 outside the pocket 4. The pattern of the O pocket 4 and the second oil pipe 7 is shown in FIG. There is a gap 10 between the surface 8 of the guide 1 facing the pocket 4 and the land portion 9 in place of the pocket 4.
There is. Generally, this gap is about 10-20 [μm].

Now, as shown in FIG. 4, when hydraulic oil pressurized by the pump 11 of the hydraulic unit 3 is supplied to the pocket 4 through the first oil pipe 6 and the throttle 6, the slide block 2 and guide 1 are connected to each other. During this period, there is a state of fluid lubrication. Pocket 4 to gap 1
The hydraulic oil that has flowed out through all seven second oil passages returns to the tank 12 of the hydraulic unit 3. Tank 1 of hydraulic unit 3
2 is atmospheric pressure, but since there is piping loss between the tank 12 and the slide block 2, the hydraulic pressure of the hydraulic oil in the second oil passage 7 of the slide pro 2 is higher than the atmospheric pressure. Therefore, the hydraulic oil leaks from the gap between the slide block 2 and the guide 1.

The present invention eliminates all of the above drawbacks, namely, provides a slide device that completely prevents leakage of hydraulic oil in a hydrostatic fluid bearing.

Below is an example? This will be explained in detail with reference to FIGS. 6 to 8.

FIG. 6 is a sectional view of the embodiment, and FIG. 8 is a hydraulic and pneumatic circuit diagram.

In FIG. 6, the slide block 14 slides along the guide 13. A pocket 15 is provided on the inner surface of the slide block 14 which is slidably fitted into the guide 13.
Hydraulic pressure is supplied from an oil pipe 16 through 17 throttles. On the outside of the pocket 16 there is a second oil pipe 18, a third oil pipe 19, and on the outside there is a #! There is 0. Here, arrow pH indicates oil pressure supply, arrow T-D indicates return of hydraulic oil to tank 24, arrow A. indicates full air supply.

Bokeh 1. G16. 2nd oil road 18. No. 3 oil road 19 and 5 -
.

The pattern of the grooves 20 is shown in FIG.

There is a gap 22 between the surface 21 of the guide 13 facing the pocket 16 and the slide plate 14. Generally, this gap is about 10 to 20 (μm).

Next, a hydraulic and pneumatic circuit diagram will be explained with reference to FIG.

The hydraulic unit 23 is for supplying all hydraulic pressure to the hydrostatic bearings. The hydraulic oil in the tank 24 is sucked up through a filter 27 by a pump 26 driven by a motor 26 and pressurized. The hydraulic pressure discharged from the pump 26 passes through the switching valve 28, the first oil pipe 16, the throttle 17, and the pocket 1.
Reach 6. Most of the hydraulic oil that has flowed out from the pocket 15 through the entire gap 22 returns to the tank 24 through the second oil passage 18.

The hydraulic oil leaking from the second oil pipe 18 to the third oil pipe 19 located further outside is forcibly sucked by a pump 30 driven by a motor 29 and returned to the tank 24 . Therefore, the hydraulic oil does not leak further outward from the third oil pipe 19. Air is supplied from an external air source 31 to the groove 20 on the outside of the third oil pipe 19. Since the hydraulic oil in the pipe 19 is sucked by the pump 30, the third oil pipe becomes negative pressure, and from the outside. Atmospheric air enters the machine and foreign objects, especially all machine tools with the slide device of the present invention,
When the slide device is assembled into a device such as the like, cutting or cutting oil may enter between the guide 13 and the slide block 14 and damage the slide device.

However, by supplying clean air to the groove 20 and making the pressure in the groove 2o higher than the total atmospheric pressure, the intrusion of foreign matter is reduced.

Also, the operating pump 30 of the second oil pipe is not provided with the third oil pipe 19.
Although it is conceivable to recover the oil in a strong and limited manner, it is not practical because the flow rate of the hydraulic oil is large and a large pump 3o is required.

As described above, in the slide device of the present invention, most of the hydraulic fluid is returned to the full hydraulic unit 23 through the second oil passage 18 provided outside the pocket 16 of the fluid bearing, and the second oil passage 18 provided outside the pocket 16 of the fluid bearing returns most of the hydraulic oil to the full hydraulic unit 23. 3 The hydraulic oil that leaked into the oil pipe 19 is forcibly returned to the hydraulic unit page 237 by the pump 3o, so the hydraulic oil is supplying clean air to the outside of the slide device, so foreign objects can be removed from the guide 13 and the slide block. There is no possibility of intrusion between 14 and 14. Therefore, there is no damage to the slide device due to foreign objects.

Furthermore, in general, when a slide device using a hydrostatic bearing is downsized, the leakage of hydraulic oil increases significantly, but with the slide device of the present invention, there is no risk of leakage, so the device can be designed compactly.

As described above, the present invention provides a compact slide device with a hydrostatic fluid bearing structure that does not leak hydraulic fluid.

[Brief explanation of the drawing]

Figure 1 is a front view of the slide mechanism, Figure 2 is the AR of Figure 1.
3 is a sectional view taken along the line B B' of FIG. 1;
A cross-sectional view of a slide mechanism using a conventional hydrostatic fluid bearing structure. Figure 4 is a hydraulic circuit diagram of a slide mechanism using a conventional hydrostatic fluid bearing structure. Figure 5 is a hydraulic circuit diagram of a slide mechanism using a conventional hydrostatic fluid bearing structure. FIG. 6 is a sectional view of a hydrostatic fluid slide device according to an embodiment of the present invention, FIG. 7 is a putter diagram of the same device, and FIG.
The figure is a hydraulic and pneumatic circuit diagram of the same device. 1.13...Guide, 2.14...Slide block, 4.15...Fist/pocket, 6.
17...Aperture, 5.16...1st oil road, 7,18...2nd oil road, 19...3rd oil road, 20 ...Groove, 31...Air source.

Claims (1)

[Claims] A hydrostatic fluid slide device comprising a guide and a slide block that slides along the guide with all of the pressure fluid flowing between the guide, a pocket provided on a surface facing the guide; A first oil pipe is provided to guide the pressure fluid through the entire throttle means into the pocket, a second oil pipe is provided outside the pocket to collect all the fluid that has flowed out from the pocket, and A third oil pipe provided on the outside of the road, a means for sucking all the fluid spilled into the third oil pipe, a groove provided on the outside of the third oil pipe, and a means for completely supplying air to the groove. A hydrostatic fluid slide device comprising: