JP2579416Y2 - Air spindle - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air spindle used for a spinning machine or the like.

[0002]

2. Description of the Related Art Conventionally, an air spindle of this kind is shown in FIG.
As shown in the figure, an impeller 32 and a flat disk 37
Are fixed, and radially blows air to the rotating shaft 31 to support the rotating shaft 31 in the radial direction. A wind receiving portion provided on the outer periphery of the impeller 32 Nozzle 35 for rotating the impeller 32 by blowing air to 38 and blowing air from both sides in the axial direction to the flat disk 37 to support the flat disk 37 and the rotating shaft 31 in the axial direction. And a static pressure axial bearing 36 for positioning.

In the air spindle, air blown from a hydrostatic radial bearing 33 supports the rotating shaft 31 in a radial direction.
The air blown out from the nozzle 35 rotates the impeller 32, and the air blown out from the static pressure axial bearing 36 supports and positions the rotating shaft 31 in the axial direction.

[0004]

However, the conventional air spindle requires a dedicated hydrostatic axial bearing 36 and a flat disk 37 in order to position the rotary shaft 31 in the axial direction. In addition, there is a problem that the number of parts is large and the cost is high.

Accordingly, an object of the present invention is to provide a compact and low-cost air spindle which does not require a dedicated component for positioning the rotating shaft in the axial direction.

[0006]

In order to achieve the above object, an air spindle according to the present invention has a rotary shaft provided with an impeller supported by a hydrostatic radial bearing and is provided on the outer periphery of the impeller. In an air spindle configured to blow air from a nozzle to a wind receiving portion to rotate the impeller, a predetermined gap is provided between each end face of the impeller and an end face of the hydrostatic radial bearing, The wind receiving portion is characterized by being formed by a substantially V-shaped concave portion in which the facing distance of the facing surface in the axial direction gradually decreases in the rotation direction of the impeller.

[0007]

According to the above construction, the axially opposed surface of the wind receiving portion is tapered so that the axially opposed distance gradually decreases in the direction of rotation of the impeller. The air blown to the wind receiving portion and hitting the axially facing surface of the wind receiving portion not only rotates the impeller, but also makes the axial position of the tip of the axially facing surface correspond to the position of the nozzle. When it is deviated from the air blowing position, an axial force is applied to the impeller to move the axial position of the tip of the axially facing surface toward the air blowing position of the nozzle, and the axial position of the tip is The impeller is moved in the axial direction so as to come to the position where the nozzle blows air.

That is, since the impeller is rotated by the air blown out from the nozzle and the axial positions of the impeller and the rotating shaft are restrained, a dedicated component for positioning the rotating shaft in the axial direction is provided. Is unnecessary, and a compact and low-cost air spindle is realized.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments.

As shown in FIG. 1, in the air spindle of this embodiment, an impeller 2 is fixed to a rotating shaft 1 movable in an axial direction, and air is blown radially to the rotating shaft 1. A hydrostatic radial bearing 3, 3 for supporting the rotating shaft 1 in the radial direction is provided. In addition, the impeller 2
A nozzle 5 for rotating the impeller 2 by blowing air in a radial direction to a wind receiving portion 6 provided on an outer periphery of the impeller 2. The side wall surfaces of the static pressure radial bearings 3, 3 are arranged so as to sandwich the side end surface of the impeller 2 from both sides with a small gap t.

As shown in FIG. 2A, the wind receiving portion 6 of the impeller 2 has an axially opposing distance D of the opposing surface 6A gradually shortened toward the rotation direction J of the impeller 2. It is formed by a concave portion having a substantially V-shaped curved shape.

In the air spindle having the above structure, the rotating shaft 1 is radially supported by air blown radially from the hydrostatic radial bearings 3, while the air blown out from the nozzle 5 is blown by the wind receiving surface 6. To rotate the impeller 2 and the rotating shaft 1 in the rotation direction J.

Further, the axially facing surface 6A of the wind receiving portion 6 has a tapered shape in which the axially facing distance D gradually decreases toward the rotation direction J of the impeller 2, so that the nozzle 5 The air blown to the wind receiving portion 6 of the impeller 2 and hitting the axially facing surface 6A of the wind receiving portion 6 not only rotates the impeller 2, but also the air shown in FIG.
As shown by a virtual line, when the axial position of the tip end S of the axial facing surface 6A is displaced from the air blowing position K from the nozzle 5, the axial facing surface 6A
An axial force F that causes the axial position of the tip S of the nozzle 5 to move toward the air blowing position K of the nozzle 5 is applied to the impeller 2 so that the axial position of the tip S comes to the air blowing position K of the nozzle 5. Then, the impeller 2 is moved in the axial direction.

That is, the impeller 2 is rotated by the air blown from the nozzle 5 and the axial positions of the impeller 2 and the rotating shaft 1 can be restrained. No special parts for positioning are required, and a compact and low-cost air spindle can be realized.

That is, according to the above embodiment, as shown in FIG. 1, the air is blown out from the hydrostatic radial bearings 3, 3 and travels along the rotating shaft 1 toward the impeller 2 side. In addition to the axial support force of the impeller 2 due to the airflow R that pressurizes the side end surface of the above, the air blown out from the nozzle 5 can be used for the axial support, and the support force can be improved.

In the above embodiment, the axially facing surface 6A of the wind receiving portion 6 of the impeller 2 is formed into a substantially V-shaped curved surface as shown in FIG. 2 (A). ), A substantially V-shaped bent surface may be used, and as shown in FIG.
A substantially V-shaped pine needle-shaped curved surface may be used. The point is that the opposing distance in the axial direction should be shorter in the rotation direction J.

[0017]

As is clear from the above description, in the air spindle of the present invention, the wind receiving portion provided on the outer periphery of the impeller has the air bearing portion facing the axially facing surface in the rotation direction of the impeller. It is formed by a substantially V-shaped concave portion whose distance gradually decreases.

Therefore, according to the present invention, the air blown from the nozzle to the wind receiving portion of the impeller and hitting the axially opposed surface of the wind receiving portion can be obtained only by rotating the impeller. When the axial position of the tip of the axial facing surface is displaced from the air blowing position of the nozzle, the axial position of the tip of the axial facing surface is directed to the air blowing position of the nozzle. An axial force is applied to the impeller, and the impeller is moved in the axial direction such that the axial position of the tip comes to the air blowing position of the nozzle.

That is, according to the present invention, the air blown out from the nozzle not only rotates the impeller but also
Because the axial position of the impeller and rotating shaft is restricted,
Unlike the conventional example, components such as a dedicated hydrostatic axial bearing for positioning the rotary shaft in the axial direction become unnecessary, and a compact and low-cost air spindle can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an air spindle according to the present invention.

FIG. 2 is a view showing a wind receiving portion of the impeller of the air spindle according to the present invention.

FIG. 3 is a sectional view showing a conventional air spindle.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Rotary shaft 2 Impeller 3 Static pressure radial bearing 5 Nozzle 6 Wind receiving part 6A Axial facing surface

Claims (1)

(57) [Scope of request for utility model registration] 1. A rotating shaft provided with an impeller is supported by a static pressure radial bearing, and air is blown from a nozzle to a wind receiving portion provided on an outer periphery of the impeller to rotate the impeller. In the air spindle described above, a predetermined gap is provided between each end face of the impeller and the end face of the hydrostatic radial bearing, and the wind receiving portion faces in the axial direction in the rotation direction of the impeller. An air spindle, wherein the air spindle is formed by a substantially V-shaped concave portion in which a facing distance of a surface is gradually shortened.