JPS6311532B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating shaft bearing device, and more particularly to a bearing device that achieves stable rotation of a rotating shaft by adjusting a gap in a bearing portion caused by friction between bearing members.

Stirring equipment in chemical plants and water treatment equipment,
In equipment having a rotating shaft that is rotationally driven by a drive device, such as a sedimentation device (clarifier, shaker, etc.) or a screw conveyor, the end of the shaft on the opposite side of the drive device is supported by a bearing.

In particular, bearings at the end of an overhanging shaft such as a stirring shaft in a stirring device, a scraper rotating shaft in a settling device such as a clarifier, or a shaker are important for preventing deflection of the shaft end, that is, for preventing shaft vibration. Further, the above-mentioned bearing is often installed internally within the main body of the device. This is because when a bearing is installed outside the equipment body, a shaft seal for the rotating shaft is required, but even if such a shaft seal is provided, a complete seal cannot be achieved due to the influence of fine solid particles in the internal liquid of the equipment body. This can be difficult, especially due to internal liquid leakage, and depending on the installation position of the shaft seal, the shaft seal may come into contact with the gas phase instead of the liquid phase as described above. This is because gas leakage may pose a danger, so it is necessary to prevent leakage of internal liquid or internal gas by installing the bearing internally and eliminating shaft seals as much as possible.

Figures 1A to 1C are diagrams showing the structures of the stirring device, sedimentation device, and screw conveyor. In each figure, A is a drive device such as a motor, B is a coupling, C is a rotating shaft, and D is a drive device. The bearing on the side, E is the shaft seal, and F or F' is the bearing on the side opposite to the drive device.

The structure of the bearing F or F' will be explained with reference to FIG. 2, taking a foot bearing in a stirring device as an example.

That is, in FIG. 2, 1 is a rotating shaft, 2 is a sleeve fitted and fixed on the outer periphery of the shaft end, and 3 is a bearing member that slides on the outer peripheral surface of the sleeve 2 and supports the sleeve 2 in a rotatable manner. With the bearing bush,
It is fitted and fixed to the inner periphery of the cylindrical bearing housing 4. Reference numeral 5 designates a bearing mount for fixedly supporting the bearing housing 4 on the bottom portion 6 of the stirring device main body.

In such a bearing device 3, foreign matter such as fine solid particles contained in the internal liquid of the stirring device body enters the sliding contact surface between the outer circumferential surface of the sleeve 2 and the inner circumferential surface of the bearing bushing 3, and the inner circumferential surface of the bearing bushing 3. The surface gradually wears out and a gap is created in the sliding contact surface,
The following problems arise.

In other words, the deflection of the shaft end caused by the play at the shaft end and the unbalanced load applied to the shaft as described above is related to the critical speed of the shaft system, and as a result, the shaft vibrates violently. .

The vibrations cause damage to the gears of the drive unit, the packing of the shaft seal, the labyrinth packing, the mechanical seal, etc.

In particular, in chemical plant equipment such as stirring equipment, it can cause damage to the rotating shaft and bearings, and there is a risk of unexpected accidents such as dangerous internal liquid or gas leaking from the shaft seal. be.

Therefore, for the above-mentioned reasons, the bearing members such as the bearing bush 3 must be constantly checked for wear or not and replaced, which makes maintenance and inspection troublesome. Another disadvantage was that it had a short life as a bearing device.

In order to solve these problems, conventional
Techniques disclosed in Japanese Patent Publication No. 35-15313, Japanese Patent Publication No. 27-211, and Japanese Patent Publication No. 37083-1983 are known.

This technique involves forming the sliding surface between the rotating shaft and the bearing member into a tapered surface, pressing the rotating shaft or the bearing member in the direction of sliding contact with the other side, and adjusting the gap between the sliding surfaces of these two members. This device is equipped with a gap adjustment means.

To briefly explain the gap adjusting means in such prior art, first, the one disclosed in Japanese Utility Model Publication No. 35-15313 uses a bearing that is provided to be movable in the vertical and axial directions with respect to a bearing holding member. The bearing is screwed into the bearing and moved upward or downward by inserting and removing the screw, thereby maintaining an appropriate gap between the bearing and the bearing.

In addition, the one disclosed in Japanese Patent Publication No. 27-211 has a cone attached to the rotating shaft that is integral with the rotational direction and movable in the axial direction, and a tapered surface that contacts the tapered surface of the outer surface of this cone is formed on the inner surface. By moving the hollow body serving as a bearing by rotating a cap nut screwed onto the end of the hollow body, the contact gap between the cone and the hollow body can be adjusted.

Furthermore, in the device disclosed in Japanese Patent Publication No. 45-37083, a spring is interposed between the end of the sleeve that carries and supports the bearing device and the bearing device, and the elastic force of the spring causes the bearing device to be attached to the shaft end. By pressing against the tapered surface, wear and tear on the contact surface with the shafted sleeve is automatically compensated for.

However, in such a conventional example, foreign matter gets into the sliding contact surface between the shaft and the bearing, and the bearing gradually wears out, and although it is a solution to the case where a play occurs in the sliding contact surface, the shaft This technology cannot be said to be completely satisfactory because it does not solve the fundamental problem of foreign matter getting into the sliding contact surface between the bearing and the bearing.

In view of the above-mentioned conventional circumstances, the present invention provides a sliding contact surface between a sleeve provided on a rotating shaft and a bearing member that freely rotates by slidingly contacting the sleeve with its inner peripheral surface or outer peripheral surface. , while forming a tapered surface, at least one of the sleeve and the bearing member is configured to be movable in the axial direction,
A space is provided between the member and a holding member that movably holds the member, and a pressurized fluid supply device is provided for supplying pressurized fluid to the space, and the fluid pressure causes the sleeve or bearing member to A pressurizing device that constantly presses and urges at least one member in the axial direction to slide into contact with the other member, and a part of the pressurized fluid supplied to the space between the sleeve and the bearing member. A foreign matter intrusion prevention device that prevents foreign matter from entering between the sliding surfaces by introducing the foreign matter into a space formed in the space and having a smaller area in the axial transverse direction than the space, prevents foreign matter from entering the bearing due to wear of the bearing member. To adjust the gap between the parts and eliminate all the various defects that arise due to the gap, thereby easing the maintenance of the bearing member and improving the life of the bearing member, and further simplifying the structure. Another object of the present invention is to provide a bearing device that prevents foreign matter from entering between the sliding surfaces and, even if foreign matter enters between the sliding surfaces, can easily discharge the foreign matter.

Embodiments of the present invention will be described below with reference to FIGS. 3 to 6.

In FIG. 3 showing an embodiment of the present invention, 1
1 is a rotating shaft; 12 is a cylindrical sleeve pivotally attached to the lower end of the rotating shaft; the sleeve 12 is fitted on the outer periphery of a small diameter portion 11a provided on the outer periphery of the lower end of the rotating shaft 11; 11b, the rotary shaft 11 is pressed and fixed by an end plate 14 fastened with bolts 13 to the lower end surface of the rolling shaft 11.

Reference numeral 15 denotes a bearing bush as a bearing member that slides on the outer peripheral surface of the sleeve 12 and supports the sleeve 12 freely in rotation, and has a cylindrical shape with a bottom.

The sliding surface between the outer circumferential surface of the sleeve 12 and the inner circumferential surface of the bearing bush 15 is formed into a tapered surface having a truncated conical outer circumferential shape that widens upward.

In this embodiment, the material of the sleeve 12 is mainly a metal material whose tapered surface 12a in sliding contact is surface-hardened, and the material of the bearing bush 15 is a copper alloy, an aluminum alloy, or a synthetic resin material. It is not limited.

A pressure device 16 supports the bearing bush 15 so as to be movable in the axial direction and constantly presses the bearing bush 15 in a direction in which it comes into sliding contact with the sleeve 12. That is, 17 is provided on the outer periphery of the bearing bush 15 and
This is a cylindrical bearing housing with a bottom that supports the bearing housing.
The bearing bush 15 is fitted into the inner periphery of the bearing housing 17 so as to be able to slide in the axial direction, and a tapered surface 15a on the inner periphery of the bearing bush 15 is constantly pressed against a tapered surface 12a on the outer periphery of the sleeve 12 by pressurized fluid, which will be described later. It is biased in the direction of sliding contact. A key groove 15b is formed in the vertical direction on the outer peripheral surface of the bearing bush 15, and a bearing housing 17 is formed in the key groove 15a.
The head of a rod-end set screw 19 screwed into the peripheral wall is inserted to stop the rotation of the bearing bush 15.

Further, although not shown, a slip key may be used instead of the bar end set screw 19. Reference numeral 20 denotes an O-ring as a sealing member interposed between the sliding contact surface between the inner circumferential surface of the upper end of the bearing housing 17 and the outer circumferential surface of the bearing bush 15.

The space A formed in the bearing bush 15 is connected to the bearing housing 1 through a pressurized fluid supply port 15c, which will be described later, and which is formed through the bottom wall of the bearing bush 15.
7, and the space B communicates with the airtight space K via a pressurized fluid supply port 17a formed in the bottom wall of the bearing housing 17. This space A is
The space B has a smaller area in the axial transverse direction than the space B.

The airtight space K is fixedly supported by bolts 23 fastened to the front bottom part 22 of the device, and a support member 24 attached to the outer periphery of the upper end of the bearing housing 17 at the upper end.
The bearing mount 21, which is fastened and fixedly supported by bolts and nuts 25, has a cylindrical shape, and the support member 24 has an annular shape.
1. The support member 24 and the bottom portion 22 of the device body form an airtight partition from the space C within the device body. Air, inert gas,
Sending a pressurized fluid such as a liquid common to the internal liquid, and sending this pressurized fluid and the pressurized fluid supply port 17a to the internal space B of the bearing housing 17 to pressurize the space B,
It is configured to press the bearing bush 15 directionally against the sleeve.

On the other hand, pressurized fluid is supplied to the internal space A of the bearing bushing 15, which is formed between the sleeve 12 and the bearing bushing 15 and has a smaller area in the axial transverse direction than the space B, so that the outer circumferential tapered surface 12a of the sleeve 12 and the bearing bushing are A foreign matter intrusion prevention device is provided to prevent foreign matter from entering between the sliding contact surfaces with the inner circumferential tapered surface 15a of 15.

This foreign matter intrusion prevention device supplies a portion of the pressurized liquid such as air, inert gas, and liquid common to the internal liquid supplied from the pressurized fluid supply device 60 shown in FIG. By supplying pressurized fluid to the space A through a pressurized fluid supply port 15c formed in and maintaining the space A at a pressure higher than the internal pressure of the device body, the pressure between the sliding surfaces of the tapered surface 12a and the tapered surface 15a is increased. The structure is designed to prevent foreign matter such as fine solid particles from entering, that is, from being bitten by foreign matter.

The pressurized fluid supply device 60 is configured to supply pressurized air from the pressurized air supply circuit 57, for example. In this pressurized air supply circuit 57, 57a is a pressurized air source including an air compressor, 57b is a pressure regulating valve, 57c is a check valve, 57b is a relief valve, 57e is a pressure gauge, 56
is a pressurized fluid supply pipe, and pressurized air whose pressure is constantly adjusted is supplied to the airtight space K by such a pressurized air supply circuit 57.

In addition, as the pressurized gas source in the above embodiment, in addition to normal air, an inert gas such as N2 gas may be used. In the above embodiment, air was used as the pressurized fluid in the airtight space K, but a liquid common to the internal liquid of the device body may also be used as the pressurized fluid. In this case, as shown in FIG. Fluid supply circuit and airtight space K
A tank 58 containing a liquid common to the internal liquid of the device body is interposed between the two and converts the pressurized air pressure into liquid pressure to apply the liquid pressure to the airtight space K. When a common liquid as a pressurized fluid has many fine solid particles in the internal liquid such as slurry, the liquid from which the fine solid particles have been removed is used.

In this configuration, when rotational driving force is transmitted to the rotating shaft 11 from a drive device such as a motor (not shown), the rotating shaft 11 is rotated while being supported by the bearing bush 15 via the sleeve 12.

Here, foreign matter such as fine solid particles contained inside the main body of the device is bitten from the boundary between the outer circumferential surface of the sleeve 12 and the upper end surface of the bearing bushing 15, as shown by the arrow in the figure. As a result, the taper 15a on the inner circumference of the bearing bush 15 gradually wears out.

However, according to the bearing device configured as described above, since the bearing bushing 15 is urged upward by the pressurized fluid, even if the tapered surface 15a on the inner circumference of the bearing bushing 15 is worn, this wear will be suppressed. The bearing bush 15 slides upward within the bearing housing 17 by the same amount, and the tapered surface 15a is pressed against the tapered surface 12a on the outer periphery of the sleeve 12, causing both tapered surfaces 12
Since the states of a and 15a are maintained, both tapered surfaces 12
There is no play between a and 15a.

Further, according to the bearing device having the above configuration, the airtight space K
By sending a pressurized fluid such as air, an inert gas, or a liquid common to the internal liquid, and sending this pressurized fluid to the space A to maintain the space A at a pressure higher than the internal pressure of the device body, the tapered surface It is possible to prevent foreign matter such as fine solid particles from entering between the sliding contact surfaces of the tapered surface 12a and the tapered surface 15a, and even if foreign matter enters between the sliding contact surfaces, the foreign matter can be easily pressurized. The fluid can be discharged, and the fundamental cause of wear on the tapered surface 15a on the inner circumference of the bearing bush 15 can be eliminated.

Furthermore, with this configuration, even if foreign matter such as slurry in the internal liquid enters the space A, the foreign matter can be easily discharged.

That is, a drain port (not shown) that communicates the space A between the bearing bush 15 and the sleeve 12 with the outside air, and a drain valve (not shown) that opens and closes the drain port are provided.

In this case, as described above, the space A and the pressurized fluid supply port 15c, the space B and the pressurized fluid supply port 17
An airtight space K is provided which communicates through the
The drain port and drain valve are provided at the bottom 22 of the device body in the airtight space K.

If a foreign substance such as a slurry in the internal liquid enters the space A, this foreign substance reaches the airtight space K via the space B and accumulates at the bottom of the device main body.

Therefore, when the drain valve is opened in this state, the pressurized fluid is present in the airtight space K, and foreign matter such as slurry can be easily discharged to the outside by the pressurized fluid, eliminating the need for troublesome work such as scraping out foreign matter. Furthermore, it is hygienic and can be used in equipment that handles food and the like, and it is possible to prevent the bearing from being affected by the accumulation of foreign matter. In particular, since the slurry is forcibly discharged by using a pressurized fluid for preventing the intrusion of foreign matter, there is no need for new means and there is an advantage that the structure can be simplified.

Moreover, if the daily drain valve is opened regularly and the amount of slurry discharged at that time is checked, abnormalities in the bearing can be easily determined. That is, if the amount of foreign matter discharged is large, it can be determined that there is an abnormality in the bearing section, and if the amount of foreign matter discharged is small, it can be determined that there is no problem.This is convenient for periodic maintenance and inspection of the bearing section, and no complicated work is required.

Also, the rotating shaft 11 expands and contracts due to temperature changes,
This expansion and contraction is absorbed by the pressure fluid through the bearing bush 15.

The embodiment shown in FIG. 3 above shows an example in which the present invention is applied to a bearing device having a structure in which the outer circumferential surface of the sleeve and the bearing bush, that is, the inner circumference of the bearing member are in sliding contact, but the inner circumferential surface of the sleeve and the bearing member The present invention may also be applied to a bearing device having a structure in which the present invention makes sliding contact with the outer circumferential surface.

This embodiment is shown in FIG. 6. In this case, a bearing member 55 is formed in the shape of a shaft on the inner circumference of a cylindrical sleeve 42 fitted on the outer circumference of the tip end of the rotating shaft 11.
is inserted, and the inner peripheral surface of the sleeve 42 and the bearing member 5
The sliding contact surface with the outer circumferential surface of 5 is a tapered surface forming a truncated conical outer circumferential surface shape that expands downward.

A sealed pressure chamber H is formed between the lower end surface of the bearing part cleaner 55 and the inner space of the bearing housing 47, and a tip pressurized fluid supply port 56a penetrates the peripheral wall of the bearing housing 47 into this pressure chamber H. The pressure chamber H is pressurized by supplying pressurized fluid from a pressurized fluid supply circuit 57 of a pressurized fluid supply device 60 as shown in FIG. It is configured to press the bearing member 55 in the direction of the sleeve 42. On the other hand, sleeve 4
2 and the bearing member 55
5. A foreign matter intrusion prevention device is provided that supplies pressurized fluid to the internal space G to prevent foreign matter from entering between the sliding contact surfaces of the inner circumferential tapered surface 42a of the sleeve 42 and the outer circumferential tapered surface 55a of the bearing member 55. It will be done.

This foreign matter intrusion prevention device is formed in the bearing member 55 so that a part of the pressurized fluid such as air, inert gas, and liquid common to the internal liquid is supplied to the pressure chamber H from the pressurized fluid supply device 60. By sending the bearing member 55 through the pressurized fluid passage 62 to the space G where the cross-sectional area is smaller than the pressure chamber H and maintaining the space G at a pressure higher than the internal pressure of the device body, the tapered surface 42a and the tapered surface 55a are The structure is such that foreign matter such as fine solid particles is prevented from entering between the sliding surfaces of the slider, that is, from being caught.

Note that when a liquid common to the internal liquid of the device main body is used as the pressurized fluid, there is no problem even if the liquid leaks from the pressure chamber H into the device main body.

The structure shown in FIG. 3 has a structure in which the bearing bush 15 is placed on the outer circumferential side of the sleeve 12.
The end surface of the bearing bushing on the sleeve side faces upward, and the fine solid particles contained in the internal liquid tend to settle on the upper end surface of the bushing, and the fine solid particles are bitten and enter from the boundary between the sleeve and the bearing bushing. Since it has a structure that is easy to use, it is preferable to use it in devices with a small amount of fine solid particles contained in the internal liquid.

Moreover, since the structure shown in FIG. 6 is such that the sleeve 42 is placed over the outer circumferential side of the bearing member 55, the end surface of the sleeve 42 on the bearing member 55 side faces downward, and the lower end surface of the sleeve 42 is covered with fine solids. Since the structure makes it difficult for particles to settle and for the fine solid particles to get caught and enter, it is effective if used in equipment in which the internal liquid contains a large amount of fine solid particles.

In the embodiments shown in FIGS. 3 and 6 above, the bearing bush 15, that is, the bearing member side, is always pressed against the sleeve side as a pressurizing device, but the sleeve side is conversely pressed against the bearing member side. It's okay.

For example, the sleeve is formed into a cylindrical shape with a partially opened inner surface, and is slidably fitted onto the outer circumference of the small diameter portion at the tip of the rotating shaft, and the outer circumferential surface of the small diameter portion of the rotating shaft and the inner circumferential surface of the sleeve are connected. A sliding key is interposed on the sliding surface to make the sleeve unrotatable with respect to the rotating shaft.

A space is provided between the tip of the rotating shaft and the inner plane of the sleeve, and the sleeve and the bearing member are arranged in such a way that the space between the bearing member and the sleeve has a smaller area in the axial transverse direction than the space. The sliding contact surface may be formed into a tapered shape.

By doing this, the pressurized fluid reaches the space between the tip of the rotating shaft and the inner plane of the sleeve through the space between the bearing member and the sleeve, and the tapered surface of the sleeve is always aligned with the tapered surface of the bearing member. is pressed in the direction of sliding contact.

As explained above, the present invention provides pressurized fluid supply.
a pressurizing device that constantly presses and urges at least one of the sleeve or the bearing member in the axial direction using the fluid pressure to slide into sliding contact with the other member; and a pressurizing device that applies a portion of the pressurized fluid to the sleeve. and a foreign matter intrusion prevention device that prevents foreign matter from entering between the sliding surfaces by guiding the foreign matter into a space airtightly maintained between the bearing member and the bearing member. It is possible to eliminate the play that occurs between the bearing member and the sleeve when the shaft is rotated, and to prevent the shaft runout of the rotating shaft as much as possible, and to ensure stable rotation of the shaft. It can effectively prevent damage to the bearing part, damage to the drive mechanism part and shaft seal part, and leakage of internal liquid or internal gas from the shaft seal part caused by these, and is especially dangerous to the internal liquid or internal gas. Safety can be increased by using

In addition, due to the above effects, even if the bearing member wears out, its function can be maintained, so the life of the bearing member can be extended, and maintenance and inspection such as checking the wear condition of the bearing member can be simplified. Therefore, it is suitable for use in internal type bearing devices where maintenance and inspection are troublesome.In this case, the shaft seal of the rotating shaft can be made unnecessary, so the fluid inside the equipment due to the shaft seal can be reduced. This has the advantage of minimizing the risk of leakage.

Furthermore, it is advantageous when a spring cannot be used as a pressurizing device due to problems such as corrosion resistance, and
Since the pressurized fluid that brings the bearing member and sleeve into sliding contact is directly used as pressurized fluid to prevent foreign matter from entering, the fundamental cause of wear on the tapered surface of the bearing member can be eliminated. In addition, a single device called a pressurized fluid supply device can constitute a pressurizing device and a foreign matter intrusion prevention device, and there is no need to provide completely separate devices to configure these devices, simplifying the device. This is advantageous in terms of production.

[Brief explanation of the drawing]

Figures 1A to 1C are schematic diagrams showing the stirring device, sedimentation device, and screw conveyor, respectively, and Figure 2 is the same as Figure 1A.
FIG. 3 is a vertical cross-sectional view showing the structure of an embodiment of the bearing device of the present invention, and FIGS. 4 and 5 respectively show modifications in the above embodiment. A schematic view showing the configuration of the pressure fluid supply device, and FIG. 6 is a longitudinal sectional view showing another embodiment. 11... Rotating shaft, 12, 42... Sleeve, 1
5... Bearing bush, 12a, 15a... Tapered surface, 15c... Pressurized fluid supply port, 16... Pressurizing device, 17, 47... Bearing housing, 17a...
Pressurized fluid supply port, 55... Bearing member, 56... Pressurized fluid supply pipe, 57... Pressurized fluid supply circuit, 60
... Pressurized fluid supply device, A, B, G ... Space, H
...Pressure chamber, K...Airtight space.

Claims (1)

[Scope of Claims] 1. A sliding surface between a sleeve provided on a rotating shaft and a bearing member that freely rotates and bears the sleeve by slidingly contacting the inner or outer peripheral surface of the sleeve is formed into a tapered surface, At least one of the sleeve and the bearing member is configured to be movable in the axial direction,
A space is provided between the member and a holding member that movably holds the member, and a pressurized fluid supply device is provided for supplying pressurized fluid to the space, and the fluid pressure causes the sleeve or bearing member to A pressurizing device that constantly presses and urges at least one member in the axial direction to slide into contact with the other member, and a part of the pressurized fluid supplied to the first space between the sleeve and the bearing member. A bearing device comprising: a foreign matter intrusion prevention device that guides foreign matter into a space that is formed and has a smaller area in the axial transverse direction than the space and prevents foreign matter from entering between the sliding surfaces. 2. The outer peripheral surface of the sleeve is in sliding contact with the inner peripheral surface of the bearing member, and the outer peripheral shape of the sleeve is tapered,
2. The bearing device according to claim 1, wherein the inner peripheral shape of the bearing member is formed such that the diameter increases toward the tip. 3 The inner circumferential surface of the sleeve is in sliding contact with the outer circumferential surface of the bearing member, and the inner circumferential shape of the sleeve has a diameter that increases toward the tip, and the outer circumferential shape of the bearing member has a tapered shape. The bearing device according to scope 1.