JPH0680230A - Sprocket mounting structure on the driven shaft - Google Patents

Abstract

(57) [Summary] (Corrected) [Purpose] Providing a sprocket mounting structure for a driven shaft that can absorb abnormal loads and enable continuous operation for a long period of time, and can be suitably used in bucket elevators for powder and granular material transportation. To do. The diameter of the inner peripheral surface of the sprocket 10 is made larger than that of the outer peripheral surface of the driven shaft 2 so that the sprocket 10 has a small gap g and is immovable in the axial direction.
The small gap g in the circumferential groove formed on the inner peripheral surface or the outer peripheral surface near both axial ends of the sprocket 10.
And a guide hole 23 for grease injection extending to the small gap g between the seal members 22 is provided in the end face and the center of the driven shaft 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for mounting a sprocket on a driven shaft, which can absorb an abnormal load and can be continuously operated for a long period of time and which can be suitably adopted in a bucket elevator for transporting powder and granular material.

[0002]

2. Description of the Related Art A so-called bucket elevator, which circulates a large number of buckets containing powder particles while vertically moving them by an endless transportation chain, is often used as a powder particle transportation device. To be

In this bucket elevator, a two-strand chain is usually used in order to mount the bucket while straddling it.

Further, as shown in FIG. 3, these two chains are arranged at the folded portion of the chain at the upper end of the frame B of the bucket elevator A and are usually called a top wheel. It is wound around a sprocket S2 to be driven, which is usually called a tail wheel, which is arranged at a folded-back portion at the lower end of the chain, and sprockets S3 to S6 to be driven which are arranged at other turning portions of the chain.

The drive sprocket S1 is attached to the drive shaft D, and the chain of the two threads is wound around the drive shaft D.
The two driving sprockets S1 and S1 are fixed to the driving shaft by using a fixing means such as a key or a spline so that their phases are aligned with each other. The drive shaft D is rotated by a drive machine such as a reduction motor.

However, the driven sprocket S2
~ S6 (In the description of the prior art, the sprocket S
That is, one sprocket for winding a two-strand chain is fixed to the driven shaft by using a fixing means, and the other sprocket has a small gap so that the sprocket can relatively slide and rotate on the driven shaft. It turned out to be good to let it fit loosely.

This is a large force generated when the sprockets on both sides of one driven shaft are fixed together due to partial uneven wear elongation of one of the two strands of the chain, biting of foreign matter, or the like. Operation stop due to twisting or damage of the driven shaft due to abnormal loads such as forces in different directions, or malfunction due to poor rotation due to this, is caused by relative sliding rotation between the sprocket and the driven shaft, that is, between the sprockets S, S on both sides. It has the function of absorbing, buffering and releasing by relative sliding rotation.

During normal operation, the sprocket and the driven shaft rotate together with the frictional force between them.

However, such small gaps are spilled from the bucket during transportation, such as corrosion and seizure that sometimes occur due to use, especially when transporting industrial raw material powders having a particle size on the order of microns. When the powder or granular material enters the small gap and solidifies, the small gap is lost and the play disappears, resulting in the above-mentioned malfunction.

When such a malfunction occurs, it is necessary to repair the sprocket by removing the sprocket and polishing the driven shaft with a file or the like, which requires a lot of labor and is inferior in maintainability.

Therefore, in order to solve the above-mentioned problem, a boss portion of the sprocket is provided with a guide hole communicating with the small gap,
A method of injecting grease into the small gap through the guide hole to prevent lubrication and seizure as well as to prevent intrusion of powder or granular material can be considered.

[0012]

However, in this method: Since the rotating boss has a guide hole, the device must be stopped once when the grease is injected. 2. When injecting grease, it is necessary to remove a sprocket and a cover body for preventing scattering that covers the chain, which are generally provided. 3. It is preferable to fill the small gap with grease in order to prevent the intrusion of the powder or granular material, but at this time, the grease flows out from the small gap, and it takes time and effort to wipe off the grease that has flowed out. 4. Even if grease is injected, the grease tends to disappear prematurely during operation, often necessitating a shutdown of the device for reinjection. Issues such as these are possible.

The present invention is based on the fact that a small gap is sealed with a sealant and a guide hole for grease injection is provided at the center of the end face of the driven shaft, so that the play can be maintained for a long period of time, resulting in abnormalities. It is an object of the present invention to provide a sprocket mounting structure for a driven shaft that absorbs and buffers loads, enables smooth operation, and reduces maintenance work.

[0014]

SUMMARY OF THE INVENTION The present invention is a sprocket mounting structure for mounting a sprocket on a driven shaft, wherein the diameter of the inner peripheral surface of the sprocket is greater than the diameter of the outer peripheral surface of the driven shaft. With this, the sprocket is attached to the driven shaft so as to have a small gap and is immovable in the axial direction, and the sprocket is recessed in the inner peripheral surface or the outer peripheral surface in the vicinity of both axial ends of the sprocket. A sealing material for sealing the small gap is arranged in the groove, and a guide hole for grease injection extending to the small gap between the seal members is provided at an end face and a central portion of the driven shaft. It is a sprocket mounting structure for the driven shaft.

[0015]

The grease can be injected from the substantial center of the axial end surface of the main shaft, so it is not necessary to stop the device and the end surface is exposed in advance to cover the sprockets and chains. It becomes possible to inject grease without removing it. 2. Can solve the problem of.

Further, since the seal members for sealing the small gap between the sprocket and the driven shaft at both ends are provided, the grease does not flow out from the small gap due to the injection of grease, the amount of grease used is reduced, and the grease overflows. Therefore, it does not contaminate the transported product. Further, the seal member also plays a role of a dust seal for the powder and granules, prevents the powder and granules from flowing into and adhering to the small gaps, and the above-mentioned 3. 4. The problem of is solved. Further, there is no increase in size as compared with the case where no sealing material is used.

INDUSTRIAL APPLICABILITY The structure for mounting a sprocket on a driven shaft according to the present invention can be suitably used for various devices such as bucket elevators, which mount two or more sprockets on a single driven shaft, particularly for a powder and granular material transportation device. The bucket elevator can be used for various transportation devices such as centrifugal discharge type, complete discharge type, induction discharge type, and the bucket itself for interval mounting, continuous mounting, and the like. Also, naturally there is no limitation depending on the type and length of the chain.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the entire driven shaft 2. The driven shaft 2 is a shaft on which a sprocket for driving other than a drive shaft D to which a so-called top wheel at the upper end of a frame B is mounted is mounted in a bucket elevator A shown in FIG. 3, for example. Make up.

The driven shaft 2 has bearings 4 at both ends of a base shaft portion 3,
Small diameter parts 5 and 5 for mounting 4 are formed.

The bearings 4 and 4 are bearing units such as a plummer block with a flange.
It is attached to the frame B that also serves as the cover. As the frame B, various types such as a frame body using a so-called shaped steel member in which dust is protected by a separate cover body are used.

The driven shaft 2 is fitted with two driven sprockets 9 and 10 around which two chains are wound around both ends of the base shaft portion 3. One of the sprockets 9 is, for example, a key 13. The boss portion 14 is attached to the base shaft portion 3 so as not to rotate relative to it, and the other sprocket 10 constitutes the sprocket attachment structure according to the present invention together with the driven shaft 2.

In this embodiment, the sprockets 9 and 10 are arranged on both sides of the bosses 14 and 15, respectively, and are provided with collars 16 and 17 which can be fixed to the driven shaft 2 in an axially adjustable manner by using set screws or the like. Positional deviation in the axial direction is prevented.

The diameter of the inner peripheral surface of the boss portion 15 of the sprocket 10 is 0.05 to 10 times larger than the diameter of the outer peripheral surface of the base shaft portion 3.
By making it about 0.10 mm, a small gap g is formed between the boss portion 15 and the driven shaft 2.

The small gap g is sealed near both ends of the boss portion 15 with sealing materials 22 and 22, and
At the center of the end surface of the driven shaft 2, the sealing material 2 is provided in the small gap g.
A guide hole 23 communicating between the two and 22 is provided.

The seal members 22, 22 are, for example, O-rings, and in the present embodiment, a groove 24 extending in the circumferential direction is provided on the outer peripheral surface of the driven shaft 2 and near both ends of the boss portion 15.
It is fitted within 24. As the sealing material 22, if a small gap g between the boss portion 15 and the driven shaft 2 is sealed to prevent the grease from flowing out and the intrusion of powder or granules from the outside, for example, a so-called oil seal is used. Other sealing materials can also be used.

The recessed groove 24 may be recessed in the inner peripheral surface of the boss portion 15, and the sealing materials 22 and 22 may be formed in the boss portion 15.
By bringing them as close as possible to the both ends of the seal material 22, it is possible to reduce the invasion amount and accumulation amount of the powder or granular material in the small gaps on the outer sides in the axial direction of the sealing material 22.

The guide hole 23 is a vertical hole 25 that opens at the center of the end surface of the driven shaft 2 and extends axially along the center line.
And a horizontal hole 26 extending in the radial direction from the rear end portion of the vertical hole 25.

The diameter of the vertical hole 25 is about 3 to 15 mm, which is suitable for injecting grease, so that the strength of the driven shaft 2 is not deteriorated, and the horizontal hole 26 has the same diameter as the vertical hole 25 or less.
In addition, the vertical hole 25 has a diameter of about 1/8 to 1/5 of the diameter of the small-diameter portion 5, and the horizontal hole 26 has a diameter of about 1/12 to 1/8.

The cross-sectional shape of the guide hole 23 may be other than circular, or the vertical hole 25 may be a through hole that opens at both ends of the driven shaft 2. At that time, for example, the opening on the fixed side sprocket 9 side may be opened. Seal it.

The lateral hole 26 opens in a small gap g between the sealing materials 22 and 22, but preferably the sealing material 2
An opening is made in the central portion in the axial direction between 2 and 22 to facilitate the filling of grease. It is also possible to employ a plurality of lateral holes 26 ....

In this embodiment, a taper screw portion is provided at the opening end of the vertical hole 25 so that the grease nipple 30 can be screwed on to facilitate the grease injection and prevent the injected grease from flowing out.

The grease injected from the guide hole 23 smoothly fills the small gap g by letting out only the air from the sealing material 22.

As a result, lubrication between the sprocket 10 and the moving shaft 2 is prevented, seizure is prevented, and relative rotational sliding due to play is enabled, and relative sliding between the sprockets 9 and 10 causes sprockets, driven shafts, and the like due to abnormal loads. When the end face of the driven shaft 2 is exposed while preventing damage to the chain or the like and stoppage of operation, the provision of the guide hole 23 at the center of the end face enables grease replenishment during operation.

Further, the sealing material 22 is used for the grease outflow,
Prevents intrusion of powder. As shown by the one-dot chain line in FIG. 2, it is also possible to form a grease retaining clasp 31 on the inner peripheral surface of the boss portion 15 of the sprocket 10, and replace the grease nipple with a rubber stopper, a bolt-shaped stopper, or the like. The sprocket mounting structure for the driven shaft of the present invention can be variously modified, such as by being used, and can be adopted in various transportation devices such as bucket elevators in which two or more sprockets are mounted on one driven shaft.

[0035]

As described above, the structure for mounting a sprocket on a driven shaft according to the present invention lubricates between the driven sprocket and the driven shaft to allow relative sliding, so that a large load, load fluctuation, etc. can be prevented. Abnormal load can be absorbed and buffered, damage to the device and operation stop can be prevented, enabling continuous operation for a long time. In addition, the sealing material prevents grease from flowing out and the intrusion of powder and granules, and the guide hole is provided in the center of the end surface of the driven shaft to facilitate grease replenishment during operation, resulting in long-term stability. You will be able to drive the car.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing an enlarged main part thereof.

FIG. 3 is a front view illustrating a bucket elevator.

[Explanation of symbols]

 2 Driven shaft 10 Sprocket 22 Seal material 23 Guide hole g Small gap

Claims (1)

[Claims] 1. A sprocket mounting structure for mounting a sprocket on a driven shaft, wherein a diameter of an inner peripheral surface of the sprocket is made larger than a diameter of an outer peripheral surface of the driven shaft to reduce the size of the sprocket. The small gap is attached to the driven shaft with a gap so as to be immovable in the axial direction and in the circumferential groove formed in the inner peripheral surface or the outer peripheral surface in the vicinity of both axial ends of the sprocket. A sprocket is attached to the driven shaft by arranging a sealing material for sealing and providing a guide hole for grease injection that extends to the small gap between the seal members at the end face and the central portion of the driven shaft. Construction.