JPH0454090B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bearing device with an axial adjustment mechanism. The present invention particularly relates to a bearing device with an axial position adjustment mechanism capable of correcting axial positional deviation due to thermal deformation or the like during rotation of a rotating shaft.

Axial positioning or position adjustment of rotating mechanical parts supported by bearings has conventionally been performed by adjusting dimensional tolerances or shims during processing. In most cases, sufficient accuracy can be obtained using this method, and there are no particular problems in use, but dynamic accuracy may be a problem, such as the center being misaligned due to axial elongation due to thermal expansion during operation. This method cannot be used for such devices. For example, if the rotating wheel position moves in the axial direction with respect to the fixed shoe during operation of a rotating wheel type continuous extruder, not only will a good formed product not be obtained, but the wheel will fit into the groove on the outer circumference of the wheel. The clearance between the shoe and the seal block or the protrusion with the orifice changes, making extrusion unstable. Moreover, in some cases, this may lead to accidents such as damage to the tool due to seizure. In order to prevent this, it is necessary to automatically restore the center deviation during operation of the device according to the amount of deviation.

The present invention was made in order to deal with such problems, and an object of the present invention is to provide a bearing device that can easily center a pivotally supported mechanical component in the axial direction during operation. do.

A bearing device with an axial position adjustment mechanism according to the present invention includes a threaded driven annular gear mounted on the outer periphery of a rotating shaft via a shaft support so as to be able to move in the axial direction integrally with the shaft; a fixed housing that threadably engages the threaded portion of the threaded driven annular gear; a drive gear that meshes with the threaded driven annular gear; a motor that rotates the drive gear; The apparatus includes a detector for detecting positional deviation, and a control device for controlling the amount of rotation of the motor using a detection signal from the detector as a feedback signal.

Embodiments of the present invention will be described below with reference to the drawings.

The illustrated embodiment is one in which the present invention is applied to a rotary wheel type continuous extruder. Fig. 1 is a longitudinal sectional view of the bearing device of the present invention, and Fig. 4 is a cross sectional view of the rotary wheel type continuous extruder. be. Note that although FIG. 4 is a cross-sectional view taken along line A--A in FIG. 1, the fixed shoe portion of the continuous extruder is omitted from FIG. 1 for clarity. To briefly explain the rotary wheel type continuous extruder with reference to FIG. 4, an annular groove 3 is formed on the outer peripheral surface of a wheel 1 fixed to a rotating shaft 2, and a groove 3 is formed in contact with a part of the outer peripheral surface of the wheel. A protrusion 5 and a seal block 9 that fit into the groove 3 are formed on the lower surface of the curved fixing shoe 4. An opening 8 is formed in the upper part of the fixed shoe 4 into which the raw material 10 to be extruded is introduced. In the illustrated example, the protrusion 5 is formed with an orifice 6 for extruding the molded product. The raw material 10 supplied through the opening 8 of the fixed shoe 4 is filled between the lower surface of the fixed shoe 4, the groove 3 of the wheel 1, the projections 5 on both ends of the fixed shoe 4, and the seal block 9, and the wheel 1 rotates in one direction. Pressure is applied by the frictional resistance of the wall surface accompanying this movement, and the extrusion molded product is continuously obtained by being extruded through the orifice 6 of the protrusion 5.

If the center position of the concave groove of the wheel 1 (position C in Fig. 1) deviates in the axial direction with respect to the fixed shoe due to thermal expansion or other causes during operation of such a rotating wheel type continuous extruder, the above-mentioned As a result, accidents such as burn-in and damage to the shoe may occur. The bearing device of the present invention corrects this axial deviation of the rotating portion.

Referring to FIGS. 1 to 3, wheel 1
The rotating shaft 2 holding the bearings 1 on both sides of the wheel 1
1 and 18, and one shaft end 2a thereof is connected to a rotational drive device (not shown) via a coupling ring 7. As shown in Fig. 3, the driving side shaft end 2a of the rotating shaft 2 is a spline shaft, and is engaged with the coupling ring 7 by spline, and the shaft end 2b on the opposite side to the driving side (Fig. 1)
is supported freely in the axial direction, thereby making the rotating shaft 2 movable in the axial direction. A bearing device according to the present invention is provided at a shaft support portion between the wheel 1 and the coupling ring 7 (drive side shaft support portion).

In the drive side shaft support portion, the rotating shaft 2 includes:
A driven ring gear 12 having a threaded portion 12a on a portion of its outer periphery is attached via a bearing 11 capable of receiving forces in radial and thrust directions. 12b is a tooth portion of the gear 12. Driven ring gear 12
is pivotally supported by a fixed housing 14 that is threadedly engaged with the threaded portion 12a of the gear, and the gear 12 is
is connected to a drive gear 16 provided at the shaft end of a position adjustment drive motor 17 via an intermediate gear 15 mounted on the housing 14 . The position adjustment drive motor 17 is attached to the housing 14, and a reduction gear, a brake device, etc. are used in combination as the case requires. A detector (not shown) for detecting a deviation of a suitable reference position on the rotating shaft 2, such as the position of the center of the wheel 1 fixed to the shaft 2 (concave groove center position C) with respect to the fixed shoe, is installed on the rotating shaft 2. It is placed on the outside.

In such a configuration, when the position adjustment drive motor 17 is driven, the driven annular gear 12 rotates via the driving gear 16 and the intermediate gear 15, and the driven annular gear 12, The bearing 11 and the rotating shaft 2 move together in the axial direction. This also causes the wheel 1 fixed to the rotating shaft 2 to move in the axial direction.
Therefore, when the center of the concave groove 3 of the wheel 1 shifts in the axial direction with respect to the fixed shoe 4 (Fig. 4) due to thermal deformation of the wheel 1 and its vicinity, the position will change by an amount corresponding to the amount of shift. The adjustment drive motor 17 is rotated to rotate the rotating shaft 2 in the opposite direction to the direction of deviation.
By moving , the center position can be corrected. In such centering, the detector detects the deviation of the reference position on the rotating shaft 2, for example, the center position of the wheel 1 fixed to the shaft, and this detection signal is used as a feedback signal to control the position adjustment drive motor, etc. The amount of rotation is controlled by a control device.

The present invention can be applied not only to rotary wheel type extruders as in the above embodiments, but also to support mechanisms for rolls in rolling mills, straightening machines, etc. In such cases, the axial centering of the rolls can be achieved by using shims, etc. This can be done easily and during operation without using any tools.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical sectional view of a bearing device with an axial position adjustment mechanism according to an embodiment of the present invention, FIG. 2 is a partial front view as seen from arrow F in FIG. 1, and FIG. FIG. 4 is a longitudinal cross-sectional view of the driving side shaft end of the rotary shaft, and FIG. 4 is a schematic cross-sectional view of the rotary wheel type continuous extruder. DESCRIPTION OF SYMBOLS 1... Wheel, 2... Rotating shaft, 11... Bearing, 14... Fixed housing, 12... Driven ring gear, 15... Intermediate gear, 16... Drive gear, 1
7...Motor.

Claims (1)

[Claims] 1. A threaded driven annular gear mounted on the outer periphery of a rotating shaft via a shaft support so as to be able to move in the axial direction integrally with the shaft, and threadedly engaged with the threaded portion of the threaded driven annular gear. a fixed housing, a drive gear that meshes with the threaded driven annular gear, a motor that rotates the drive gear, a detector that detects axial positional deviation of the rotation shaft during operation of the rotation shaft, and the detector. A bearing device with an axial position adjustment mechanism, comprising: a control device that controls the amount of rotation of the motor using a detection signal of the motor as a feedback signal.