JP2902188B2 - Shaft sealing device for kneader rotor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft sealing device for a kneader rotor for kneading a material in which powder and granules are mixed.

[0002]

2. Description of the Related Art In general, a powder seal (shaft seal) is different from a liquid seal in that when a powder (especially a hard powder) enters a seal surface, the seal material is greatly damaged. is necessary. Conventionally, as a rotor shaft sealing device of a kneader for kneading a powder material such as a synthetic resin kneading material (hereinafter simply referred to as a material), there is one shown in FIG. 3 (for example, see Japanese Utility Model Publication No. 60-115). The shaft sealing device includes a sleeve 44 externally fitted to a drive shaft portion 42A of a kneading rotor 42 rotatably fitted in a housing 41 having a material supply port 40 in an upward opening shape, and a shaft sealing housing 43 ( The drive end frame includes an oil seal 45 and a synthetic resin ring 46.

In the shaft sealing housing 43, a space 47 is formed between the oil seal 45 and the synthetic resin ring 46, and a gas supply path 48 communicating with the space 47 is provided. A gas (air or N ₂ gas) flows from the gap 49 between the ring 46 and the sleeve 44 toward the material supply port 40 as shown by an arrow in FIG. 3, and the gap C between the kneading rotor 42 and the front end of the shaft sealing housing 43. Therefore, the material, especially the powder, is prevented from flowing.

The oil seal 45 is used without lubrication, and its lip 45A is pressed against the outer peripheral surface of the sleeve 44 by a ring-shaped spring 50.
Is adjusted by adjusting the power of

[0005]

In the above conventional example, the powder of the material can be prevented from flowing into the drive shaft portion 42A, but the oil seal 45 is used in a manner different from the original use. Therefore, the lip 45A or the lip contact portion of the sleeve 44 wears quickly, so that the spring force of the spring 50 of the oil seal 45 must be properly adjusted, and the oil seal 45 and the sleeve 44 are severely damaged. There are problems such as frequent replacement.

SUMMARY OF THE INVENTION The present invention has been made in view of the above situation, and has as its object to reduce the wear of the seal portion, adjust the spring pressure of an oil seal or the like, and frequently change the oil seal or the like. It is an object of the present invention to provide a shaft sealing device for a kneading rotor which is unnecessary and has high durability.

[0007]

According to the present invention, the following technical measures have been taken in order to achieve the above object. That is, according to the present invention, a kneading rotor is rotatably fitted in a housing having a powdery and granular material supply port in an upward opening shape, and a drive shaft portion of the rotor is supported by a shaft-sealing housing and driven. In a kneader in which the material is prevented from flowing into the shaft portion, a sleeve is fixed to the outer periphery of the drive shaft portion, and an annular space is formed between the sleeve and the inner periphery of the shaft sealing housing. At the same time, a fixing ring having a ventilation gap between the sleeve and the material supply port is fitted, and an axial run-out follow-up ring composed of a plurality of divided bodies is slidably contacted with the plurality of rows of sleeves in the space. The gas supply passage is provided so as to form a gas conduction gap between the divided bodies in the direction, and a gas supply path is communicated with the outer peripheral side space of the shaft run-out following ring.

Further, according to the present invention, the shaft sealing housing is provided with an auxiliary gas supply passage communicating with the outer periphery of the sleeve between the fixed ring and the shaft run-out follower ring, and the auxiliary gas supply passage and the gas supply passage are provided. Are characterized in that the gas supply pipes are connected via respective regulators.

[0009]

According to the present invention, the gas supplied from the gas supply path into the annular space of the shaft sealing housing is supplied to the sleeve and the follow-up ring from the gaps formed between the circumferential divisions of the respective shaft run-out follow-up rings. The gas flowing axially forward and backward through the gap between the inner peripheral surface of the shaft sealing housing located in the axial front and rear direction and flowing forward in the axial direction passes through the gap between the fixed ring and the sleeve, and the kneading rotor and the inside of the shaft sealing housing are separated. It flows into the housing through a gap with the peripheral surface.

Therefore, the material introduced into the housing from the material supply port does not flow into the gap between the kneading rotor and the inner peripheral surface of the shaft sealing housing, and the sealing portion is protected. Then, even if the inner peripheral surface of the split shaft follow-up ring that is in contact with the outer peripheral surface of the sleeve is worn, the split body is urged by a spring in the axial center direction to follow and contact, so the gap is automatically adjusted. The sealing function is maintained.

Further, the gas of the pressure adjusted from the auxiliary gas supply path is supplied to the outer periphery of the sleeve between the fixed ring and the shaft run-out following ring, and the gas flowing out of the gap between the kneading rotor and the inner peripheral surface of the shaft sealing housing is removed. The pressure is properly controlled and an optimal sealing function is ensured.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2, reference numeral 1 denotes a kneader housing;
2 is a kneading rotor whose screw portion 2A is the housing
1, a sleeve 3 is externally fitted and fixed to the drive shaft 2B at the rear end, and a shaft seal housing fixed to the rear end of the housing 1 or the front end of a drive end frame (not shown). 4 is provided with four sets of shaft run-out tracking rings 5, 6, 7, and 8.

In the shaft sealing housing 4, an annular space 9 in which the shaft runout follow-up rings 5 to 8 are fitted is provided in the rear half of the inner periphery thereof.
Are formed, and ventilation gaps 10 and 11 are formed before and after that, and a fixing ring fitting groove 12 is formed at an intermediate position of the front half, and the ventilation gap is formed between the groove 12 and the outer peripheral surface of the sleeve 3. A fixing ring 14 is fitted so as to form an annular gap 13 for use, and an auxiliary gas supply space 15 is provided between the fixing ring 14 and the ventilation gap 10.

The ventilation gap 10, the auxiliary gas supply space 15, and the ventilation annular gap 13 are formed by a gas formed between the outer periphery 2 C of the blade rear end of the kneading rotor 2 and the inner peripheral surface of the front end of the shaft sealing housing 4. It communicates with an outflow gap 16 which is close to an upwardly open material supply opening 17 in the housing 1. Further, the shaft seal housing 4 is provided with a gas supply path 18 and an auxiliary gas supply path 19 communicating with the spaces 9 and 15, respectively, and the gas supply paths 18 and 19 are provided with respective pressure regulators. Two
Gas supply pipes 22 and 23 are connected to each other via the gas supply pipes 0 and 21, and the pressure of the gas supplied to the space 9 and the space 15 is individually controlled. Powder can be effectively prevented from flowing from the gap 16 to the outer periphery of the drive shaft portion 2B.

Reference numerals 24 and 25 denote on-off valves, 26 and 27 denote pressure gauges, and the gas supply pipes 22 and 23 are connected to a main supply pipe 28. As shown in FIG. 2, each of the shaft runout follow-up rings 5 to 8 comprises a divided body 29 divided into three in the circumferential direction, and a predetermined gas conduction gap is provided between the circumferential end faces of each divided body 29. The inner peripheral surface of each divided body 29 is pressed against the outer periphery of the sleeve 3 with a predetermined pressure by a coil spring 31 wound around the outer periphery, and the two are always kept in a state of surface contact, that is, a sealed state. It has become so. The divided body
The number of divisions of 29 is not limited to three, but may be two or other.

The following rings 5, 6, 8 are locked by locking pins 32, 33 so as not to rotate with respect to the shaft sealing housing 4, and are movable in the radial direction. In each of the divided bodies 29, a coil-shaped biasing spring 35 is fitted in a hole 34 formed in the axial direction from the follower ring 6 side, and the other rings 5 except the adjoining surfaces of the follower rings 6 and 7 are fitted. ,
6 and 7, 8 and the axial end face of the space 9 maintain a sealed state with an appropriate pressure.

In the above embodiment, the shaft runout follower ring 5
8 and the fixing ring 14 are preferably made of synthetic resin such as Teflon mixed with a reinforcing agent such as glass fiber. Note that the pressure of the gas introduced into the auxiliary gas supply path 19 is set to be lower than the pressure of the gas introduced into the gas supply path 18 so as not to obstruct the flow of the gas flowing out of the ventilation gap 10 into the space 15. In addition, the purpose is to optimize the gas flow flowing out of the ventilation gap 10 only. To this end, separate regulators 20, 21 are provided for each tube 22, 23.

According to the present invention, the space 9 is
The gas (air or N ₂ gas) supplied to the inside is separated by the gap 30 between the divided bodies 29 of the shaft run-out following rings 5 to 8 and the rings 6 and 7.
Between the front ventilation gap 10 and the rear ventilation gap 11
The gas that has flowed out from the front and back in the axial direction, respectively, and
An annular gap 13 between the sleeve 3 and the fixed ring 14 via the auxiliary gas supply space 15 and a gap between the outer periphery 2C of the blade rear end of the kneading rotor 2
It flows through the housing 16 and into the housing 1 at a predetermined pressure.

Therefore, the material supply port 17 to the housing
In particular, the powder of the material supplied in 1 cannot enter the drive shaft portion 2B from the gap 16 between the rear end outer periphery 2C of the kneading rotor 2 and the shaft sealing housing 4 and sufficiently exerts a sealing function. . Even if the inner peripheral surfaces of the shaft run-out follow-up rings 5 to 8 and the outer peripheral surface of the sleeve 3 are worn, the inner peripheral surfaces of the shaft run-out follow-up rings 5 to 8 are pressed against the outer peripheral surface of the sleeve 3 by the coil spring 31. Then, the sealing state is automatically secured. Further, the gas from the supply path 18 is supplied to the following rings 5 to
The cooling action of 8 is performed. The gap 30 functions not only for gas conduction but also for the ring to be worn down to a certain amount of wear by the outer peripheral spring so that the shaft can follow the shaft runout.

The present invention is not limited to the above-described embodiment, and the design can be changed as appropriate.

[0021]

According to the present invention, as described above, a kneading rotor is rotatably fitted in a housing having a powdery or granular material supply port in an upward opening shape, and a drive shaft portion of the rotor is a shaft sealing housing. In a kneader that is supported by the shaft and prevents the material from flowing into the drive shaft, a sleeve is fixed to an outer periphery of the drive shaft, and a sleeve is fixed to an inner periphery of the shaft sealing housing. An annular space is formed therebetween, and a fixing ring having a ventilation gap between the sleeve and the material supply port is fitted to the material supply port side. A gas supply passage is provided so as to be in sliding contact with the sleeve and so as to form a gas conduction gap between the divided bodies in the circumferential direction, and a gas supply path is communicated with the outer peripheral side space of the shaft run-out following ring. Because it is Portion becomes surface contact, a clearance of wear is small and the seal surface is adjusted automatically and properly,
This eliminates the need for any manual adjustment work, improves durability, and simplifies maintenance management.

Further, according to the present invention, the shaft sealing housing is provided with an auxiliary gas supply passage communicating with the outer periphery of the sleeve between the fixed ring and the shaft run-out follower ring, and the auxiliary gas supply passage and the gas supply passage are provided. Are characterized in that the gas supply pipes are connected via individual regulators, respectively, so that the pressure of the sealing gas can be properly adjusted and perfect sealing can be performed.

[Brief description of the drawings]

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

FIG. 2 is a side view of the shaft run-out tracking ring.

FIG. 3 is a longitudinal sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Housing 2 Kneading rotor 2B Drive shaft part 3 Sleeve 4 Shaft sealing housing 5 Axis run-out follow-up ring 6 Axis run-out follow-up ring 7 Axis run-out follow-up ring 8 Axis run-out follow-up ring 9 Space 13 Vent gap 14 Fixed ring 15 Space 17 Material supply port 18 Gas supply path 19 Auxiliary gas supply path 20 Regulator 21 Regulator 22 Gas supply pipe 23 Gas supply pipe 29 Divided body 30 Gas conduction gap

Claims (2)

(57) [Claims] 1. A kneading rotor is rotatably fitted in a housing having a powdery material supply port in an upward opening shape,
In a kneader in which a drive shaft portion of the rotor is supported by a shaft sealing housing and the material is prevented from flowing into the drive shaft portion, a sleeve is fixed to an outer periphery of the drive shaft portion, On the inner circumference of the shaft sealing housing, an annular space is formed between the sleeve and the sleeve, and a fixing ring having a ventilation gap between the sleeve and the material supply port is fitted on the material supply port side. The shaft follow-up ring composed of the divided bodies is disposed so as to slide in contact with the plurality of rows of sleeves and a gas conduction gap is formed between the divided bodies in the circumferential direction. A shaft sealing device for a kneader rotor, wherein a supply path is communicated. 2. The shaft sealing housing is provided with an auxiliary gas supply passage communicating with the outer periphery of the sleeve between the fixed ring and the shaft run-out follower ring, and the auxiliary gas supply passage and the gas supply passage are individually provided. 2. The shaft sealing device for a kneader rotor according to claim 1, wherein a gas supply pipe is connected via an adjuster.