JP3453605B2 - Rotary shaft sealing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary shaft seal mechanism, and as a seal mechanism formed for the purpose of dustproofing and waterproofing the rotary shaft portion of various mechanisms, it is an advantageous seal mechanism with low resistance especially under high speed rotation conditions. Is to provide.

[0002]

2. Description of the Related Art Sealing is performed between a rotary shaft body and a fixed body such as a bearing portion thereof when such a mechanism is operated in an environment where dust or the like exists. . That is, since dust and the like enter and adhere to the bearing mechanism, smooth rotation operation is hindered, wear on both the shaft body and the bearing body is increased, and the durability thereof is reduced. It is essential to seal the bearings to avoid disadvantages. Particularly, in recent years, rolls and other rotating bodies often reach speeds of 10 m or more per second, and since a large amount of dust and the like also cause great wear due to intrusion and adhesion thereof, sealing of the bearing is indispensable.

However, in the conventional sealing mechanism as described above, it is common to fill the voids with a rubber material or a porous material. That is, when the filling material press-fitted into the void portion is attached to the rotating member, centrifugal force acts, and the solid filling state at the corner is relaxed. Therefore, a fixing material such as rubber is attached to the fixing member, and the filling material is It is common to make contact with the rotating member.

Further, a liquid sealing mechanism is partially used, and in particular, a sealing mechanism using a liquid film formed by discharging from a nozzle portion is also used, that is, in this case, sealing is performed without sliding between solid members. The purpose can be achieved. Further, a labyrinth mechanism is also known as a non-contact type seal system.

[0005]

The conventional rotary shaft seal mechanisms as described above are industrially preferable, even though each of them has a sealing effect and has a definite disadvantage. I can't do it.

That is, according to the above-mentioned general method, in order to enhance the sealing performance, it is required to fill the elastic or porous material in a solid state, while the filling material in such a solid state is made of the material. However, no matter how good the lubricity is, the abrasion resistance to the rotary member is increased and the wear cannot be avoided, and the rotational driving force in such a state is inevitably large. Of course, the life of the sealing material is extremely short, and the sealing action is greatly reduced except for the initial setting due to fire cracking, and often does not serve as the sealing material. Therefore, there is no choice but to put them in an intermediate state, but in this case, both of these disadvantages are provided even if they are to a low degree.

Even if there is no such disadvantage, the liquid sealing mechanism using the liquid film discharged and formed by the nozzle requires the liquid pressure forming means for discharging from the nozzle, and the equipment structure becomes complicated. Further, the labyrinth mechanism cannot achieve the sealing purpose at all when the rotating body such as the roll body is stationary.

Further, in order to obtain a sealing effect even when the applied mechanism is in an operation stop condition, a liquid film by nozzle discharge or a special sealing mechanism in place of it is always formed in either the liquid sealing or the labyrinth mechanism. Therefore, the operating cost or equipment cost for sealing is significantly increased.

[0009]

Means for Solving the Problems The present invention has been studied to solve the technical problems of the conventional ones described above, and has a preferable function by adopting a sealing means utilizing centrifugal force. It has been successful and is as follows.

(1) A rotary shaft portion sealing device between a rotary shaft portion body and a fixed portion body such as a bearing portion thereof, which is attached to the rotary shaft portion body and rotates the rotary shaft portion body. A centrifugal force sealing mechanism utilizing centrifugal force is provided, and the centrifugal force sealing mechanism is an elastic seal material formed by inserting an inner cavity. A water draining hole is formed in the inner cavity, and the water draining hole is formed. A rotary shaft seal device in which a valve body having a check function that can be opened and closed is provided in the valve body, and the drainage hole is opened by a centrifugal force generated by rotation of the rotary shaft.

[0011]

(2) The rotary shaft seal mechanism of the above (1), which is an elastic member having an L-shaped cross section, which is provided with a free end side lip portion that is tilted by centrifugal force action on the inner circumference side of the rotation radius. .

[0013]

A centrifugal seal provided on the rotary shaft body as a seal structure between the rotary shaft body and a fixed body such as a bearing portion thereof and utilizing centrifugal force generated by rotation of the rotary shaft body. By using the mechanism, the sealing force is exerted by utilizing the rotating force of the rotating shaft body, and the seal is formed under the condition of low resistance or driving force.

A cross-section L provided with a free end side lip portion on the inner circumference side of the radius of gyration in which the centrifugal force seal mechanism is tilted by centrifugal force.
-Shaped elastic member, the fixing mechanism is formed on the outer peripheral side of the rotation radius of the centrifugal seal mechanism so that the seal mechanism can rotate under the action of centrifugal force due to the rotation of the rotary shaft body. The seal is effectively joined to the body, and the free end side lip portion formed on the inner peripheral side of the rotating inner diameter reduces or separates the seal joining force from the fixed portion body.

That is, the centrifugal force sealing mechanism described above forms a sealing state between the fixed portion body on the inner peripheral side of the rotation radius by the restoring force of the rubber or other sealing material under low speed or stop condition, and the rotating shaft portion By releasing the sealing state due to the restoring force of the sealing material by the centrifugal force action due to the high speed rotation condition of the body, a joint seal is formed under low speed or stop condition with less friction resistance or wear, and friction resistance or wear The joint seal is loosened or released at the time of high speed rotation at a high speed, so that the seal state is always formed, and the seal is formed without requiring a special driving force such as at the time of stop and the seal mechanism. And, the durability of the bearing component body is sufficiently enhanced.

[0016]

Further, the centrifugal force sealing mechanism is an elastic sealing material formed by inserting the inner cavity, and a water drain hole is formed in the inner cavity, and the water drain hole has a check function capable of opening and closing. By providing a valve element and opening the water draining hole by the centrifugal force action by the rotation of the rotating shaft, the water draining hole is closed under stop or low rotation speed condition, and the centrifugal force action by the high speed rotation is performed. Open the water drain hole to drain the water that has penetrated inside.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A concrete embodiment of the present invention as described above will be described with reference to the accompanying drawings. As shown in FIG. 1, a rotary shaft body 16 and a fixed body 18 such as a bearing portion thereof are provided. The centrifugal force seal mechanism 1 is adopted between the rotating shaft body 16 and the centrifugal force seal mechanism 1 for mounting the centrifugal force seal mechanism 1.
An annular mounting seat 4 is formed over the entire circumference of the mounting seat 4, and a joint seat 5 located inside the mounting seat 4 is projectingly provided on the fixing portion body 18.

The centrifugal force seal mechanism 1 is made of an elastic material such as rubber having a L-shaped cross section, and a metal piece 1a such as a ring-shaped steel piece is attached to the attachment end surface and is stably set on the attachment seat 4. However, it is a weight portion 11 in which the free end side lip portion is formed as a thick portion on the inner circumference side of the rotation radius of the seal mechanism 1, and the thickened weight portion 11 is the weight portion of the joint seat 5 described above. A fixing portion 12 for the mounting seat 4 is formed so as to face the outer surface and on the outer peripheral side of the rotation radius of the seal mechanism 1.

[0020]

In the centrifugal force sealing mechanism 1 according to the present invention, the mounting seat 4 and the joining seat 5 have a relatively large space,
Alternatively, under a use condition in which a relatively large centrifugal force acts, a limiting portion is provided on the fixed side to adjust and limit the operating range of the thick portion 11 when the rotating centrifugal force acts. That is, the action of the centrifugal force by the thick portion 11 is appropriately controlled to suppress the generation of the gap between the free end of the seal mechanism 1 and the joint seat 5 at the time of high speed rotation, and the limiting portion is appropriately made of a porous material or the like. Under the conditions of rotational centrifugal force, cushioning is used to limit the occurrence of play between the joint seat 5 and the free end side of the seal mechanism to form an effective dustproof and moistureproof seal relationship.

That is, the present inventors have specifically made the inner diameter of the thickened lip portion 11 on the free end side of the seal mechanism 1 13
Manufacture a rubber seal member of about 0 to 140 mm,
Lip part 11 when this is installed and driven as shown in FIG.
According to the result of studying the behavior of the
It was confirmed that the lip portion 11 floated away from the joint seat 5 at a speed of about m / sec, and the gap rapidly expanded after such lift-off, for example, a rotational peripheral speed of 14 m.
At / sec, the gap is about 2 to 7 times larger than when floating.

The generation of the above-mentioned gap means that dust, water and the like enter the inside of the bearing and the like.
While forming a detached state from the fixed part, the rapid expansion of the gap is controlled by forming a limiting part in the fixing part 12, and there is no floating even under a high-speed rotation condition exceeding 20 m / sec. It is possible to effectively control the intrusion of dust and the like.

In any case, the seal mechanism 1 according to the present invention as described above has an elastic restoring action (tension margin) of the seal mechanism 1 itself under a stop condition or a low speed rotation condition.
Although the lip portion 11 is joined and sealed to the joining seat 5, the rotating portion such as a roll is rotated at a high speed so that a centrifugal force acts on the thick lip portion 11 to overcome the tension. As a result, the joining seal portion with respect to the joining seat 5 can be detached or the joining force can be reduced.
The joint sealing force between and is reduced, the frictional resistance increase in the joint seal portion is avoided, and the wear of each member is reduced or eliminated.

In the embodiment of the present invention, as is apparent from FIG. 1, the gap between the mounting seat 4 and the fixed part 18 is reduced as much as possible, and the end faces of the parts 16 and 18 are tapered. Water such as cooling water that has entered the upper clearance 14 in FIG. 1 is guided to the lower portion and discharged from the lower tapered surfaces 13a and 14a. A drainage hole 17 as shown in FIG. 2 and below can be provided in the portion, and the water that has entered the joint seat 5 portion of the fixed body 18 is led out from the drainage hole 17 particularly in the lower side of FIG. Can be dropped appropriately.

In the present invention, the valve body 6 can be provided in the water drain hole 17 of the seal mechanism 1 as described above as shown in FIG. That is, in the structure shown in FIGS. 2 and 3, the valve body 6 is provided at the portion where the water drainage hole 17 of the seal mechanism 1 is formed, and the valve body 6 has the fixed portion 7
It is fixed in the inner part of the seal mechanism 1 by means of the seal mechanism 1, and when the rotation is stopped or at low rotation speed, the water drain hole 17 is closed as shown in FIG. The free end of 6 floats up, the water drain hole 17 is opened, and the moisture that has entered inside is discharged.

The valve body 6 shown in FIGS. 2 and 3 can be modified and implemented as shown in FIG. 4 or 5. That is, these FIG. 4 and FIG. 5 are those in which a ring-shaped portion having a small cross-sectional structure similar to the seal mechanism 1 is set as the valve body 8 in the inner cavity 1a of the seal mechanism 1.
A weight portion 11 is formed at the free end portion located on the inner diameter side, and the free end portion is separated from the inner surface of the seal mechanism 1 and drained from the water drain hole 17 by the action of centrifugal force under high speed rotation conditions.

As shown in FIG. 5, the valve body 8 is provided with a projection 10 which fits into the drainage hole 17 in a plug-like manner so as to completely close the rotation or stop the rotation at a low speed.

According to the present invention as described above, the seal member 4 seals when the rotating shaft body 1 is stopped or rotated at low speed, and the sealing by the seal member 4 is frictional when stopped or rotated at low speed. It is clear that there is no or negligible generation of resistance or frictional heat.
In addition, the rotation of the rotating shaft body at a high speed reduces or releases the sealing by the sealing material 4. It is clear that the sealed state can be maintained from the stop condition to the high-speed rotation condition to form a seal having substantially no friction, and that no special power or pressurization is required for the seal.

[0030]

According to the present invention as described above, an appropriate sealing relationship is formed under low speed or stop conditions, and under high speed rotation conditions, frictional resistance of such contact seal is preferably utilized by utilizing centrifugal force. By forming a reduced or released state, avoiding wear and frictional heat of members, and avoiding wear and frictional heat of members under high-speed rotation conditions, always forming a stable sealing relationship under advantageous conditions,
Since it can be maintained and a sufficient reduction of the rotation driving force can be obtained, it is an invention having a great industrial effect.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view showing a main part relationship of a sealing device according to the present invention.

FIG. 2 is an enlarged cross-sectional view showing a modified example of the centrifugal force sealing mechanism.

FIG. 3 is an enlarged cross-sectional view showing a valve body operating state of the one shown in FIG.

FIG. 4 is an enlarged sectional view showing still another example of the centrifugal force sealing mechanism according to the present invention.

FIG. 5 is an enlarged sectional view showing another centrifugal force sealing mechanism according to the present invention.

[Explanation of symbols]

1 Centrifugal force seal mechanism 4 mounting seat 5 joints 6 valve body 7 Fixed part 8 valve 10 Plug-shaped protrusion 11 parts by weight (thickened lip) 12 Fixing part 13 Tapered surface 13a Lower tapered surface 14 Tapered surface 14a Lower tapered surface 16 rotating shaft body 17 Drainage hole 18 Fixed part

Front Page Continuation (72) Inventor Michio Kitawaki 538 Nijoshita, Kawaramachi, Nakagyo-Ku, Kyoto Prefecture, Rouichi No Funairi, Higashiiri 538 (72) Inventor Akio 3-1-1, Kizaki, Akashi-shi, Hyogo 11-503 ( 56) References JP-A-7-55012 (JP, A) Actually open 2-93571 (JP, U) Actually open 59-85460 (JP, U) Actually open 62-156667 (JP, U) (58) ) Fields surveyed (Int.Cl. ⁷ , DB name) F16J 15/32 311 F16J 15/32 301

Claims (2)

(57) [Claims] 1. A rotary shaft portion sealing device between a rotary shaft portion body and a fixed portion body such as a bearing portion thereof, the rotary shaft portion body being attached to the rotary shaft portion body and rotating by the rotation of the rotary shaft portion body. A centrifugal force sealing mechanism utilizing centrifugal force is provided, and the centrifugal force sealing mechanism is an elastic seal material formed by inserting an inner cavity. A water draining hole is formed in the inner cavity, and the draining hole is formed. A rotary shaft seal device, wherein a valve body having a check function that can be opened and closed is provided, and the drainage hole is opened by a centrifugal force caused by rotation of a rotary shaft. 2. The centrifugal force sealing mechanism is an elastic member having an L-shaped cross section, which is provided with a free end side lip portion which is tilted by centrifugal force action on an inner peripheral side of a radius of gyration. Rotary shaft seal device.