JPH0321465Y2 - - Google Patents

Description

[Detailed explanation of the invention] Purpose of the invention (industrial application field) This invention is designed to improve the balance of rotating workpieces such as grindstones and circular saws, mechanical parts such as gears, impellers, and flywheels, and various other rotating products. The present invention relates to a rotational balance detection device used for detection.

(Prior Art) Conventionally, this type of rotational balance detection device attaches a workpiece to one end of a spindle that is rotatably supported by a frame, rotates the workpiece together with the spindle, and measures vibrations of the spindle. This allows the balance of the workpiece to be detected.

(Problem to be solved by the invention) However, in this conventional device, since the spindle is supported by a frame via a bearing, etc., vibrations of the spindle include vibrations occurring in the bearing part in addition to unbalance of the workpiece. There was a problem in that the balance of only the workpiece could not be accurately detected because it included vibrations or vibrations of the motor for rotating the spindle.

Structure of the invention (Means for solving the problem) This invention was made by focusing on the problems mentioned above.
A spindle 4 equipped with a mounting portion 13 for integrally rotatably mounting a workpiece W is rotatably supported in a bearing hole 2 of a frame 1, and a bearing surface 5 of this bearing hole 2 has a mounting portion 13 attached thereto for integral rotation. A first static pressure generating section 21 for applying static pressure in orthogonal directions, and a second static pressure generating section 2 for applying static pressure along the axis of the spindle 4.
3 to generate static pressure between the bearing surface 5 and the spindle 4, and a detected object detected by the vibration detector 18 near the work W attachment part 13 of the spindle 4. 14 is fitted externally so as to be relatively rotatable, and this detected object 1
4 is provided with a third static pressure generating section 24 that generates static pressure between the detected object 14 and the spindle 4.

(Function) Therefore, in the rotational balance detection device of this invention, the spindle 4 is rotated in a nearly non-vibration state due to the static pressure of the static pressure generators 21 and 23, so the vibration of the workpiece W is suppressed by the attachment. The vibration of the object to be detected 14 fitted around the portion 13 via static pressure is detected accurately by the vibration detector 18 .

(Example) Hereinafter, an example that embodies this invention will be described based on the drawings.

As shown in FIG. 1, a frame 1 is formed with a bearing hole 2 extending vertically, and a large diameter portion 3 is provided in the middle of the bearing hole 2. As shown in FIG. A spindle 4 is installed in the bearing hole 2.
is inserted therethrough and rotatably supported by the bearing surface 5 of the bearing hole 2. A collar portion 6 that fits into the large diameter portion 3 is formed in the middle portion of the spindle 4, and a connecting shaft portion 8 that projects downward through the through hole 7 of the frame 1 is formed on the lower end surface of the spindle 4. It is provided. The connecting shaft 8 is connected to a drive motor 10 via a vibration-absorbing coupling 9, and as the drive motor 10 rotates, the spindle 4
is rotated at high speed within the bearing hole 2.

Further, a chuck 13 as a mounting portion is attached to the small diameter shaft portion 12 protruding from the upper end of the spindle 4, and the chuck 13 is used to attach rotating workpieces, mechanical parts, or various rotating products that require balance detection. A work W is attached to the spindle 4 so that it can rotate integrally with the spindle 4.

On the other hand, as shown in FIG. 2, a detection object 14 is fitted onto the small-diameter shaft portion 12 through an insertion hole 15 at one end of the small-diameter shaft portion 12 so as to be relatively rotatable. This detected object 14
A rod-shaped sliding portion 17 is integrally formed at the other end, and the sliding portion 17 is slidably inserted into a sliding hole 16 horizontally extending through the upper end of the frame 1. There is. Then, the sliding portion 17 of the detected object 14
A vibration detector 18 such as an acceleration pick-up or gap sensor is arranged near the vibration detector 18, and the vibration detector 18 is connected to a vibration display device 19 having a built-in microcomputer and a numerical display section.

Incidentally, in the rotational balance detection device of this embodiment, a plurality of first oil pockets 21 are recessed so as to surround the outer surface of the spindle 4 on the bearing surface 5 of the bearing hole 2, and a plurality of first oil pockets 21 are recessed so as to surround the outer surface of the spindle 4. The pressure of the pressurized oil 22 supplied by the device into each first oil pocket 21 causes static pressure to be generated between the bearing surface 5 and the spindle 4 in a direction perpendicular to the axis of the spindle 4. ing. Furthermore, a plurality of second oil pockets 23 are arranged in an annular row on the upper and lower surfaces of the large diameter portion 3 of the bearing hole 2 so as to face the upper and lower surfaces of the flange 6 of the spindle 4. The pressure of the pressure oil 22 supplied to the oil pocket 23 of the spindle 4
The static pressure is adapted to act along the axis of.

Furthermore, as shown in FIG.
A plurality of third oil pockets 24 are formed on the circumferential surface of the insertion hole 15 for applying the static pressure to the small diameter shaft portion 12 of the spindle 4. On the other hand, a fourth oil pocket 25 is provided on the sliding surface of the sliding hole 16 of the frame 1 for generating the static pressure against the sliding portion 17 of the detected object 14.
There are several.

Next, the operation of the rotational balance detection device configured as above will be explained.

Now, when the drive motor 10 is started with no workpiece W attached, the spindle 4 and the workpiece W are rotated together at high speed. At this time, the frame 1 is removed by the first and second oil pockets 21 and 23.
Since static pressure is acting between the bearing surface 5 and the spindle 4, the rotational resistance of the spindle 4 is almost solely due to the shear stress of the pressure oil 22, and the spindle 4 is not affected by vibrations of the drive motor 10, etc. It rotates with almost no vibration. Therefore, check 13
If a vibration occurs in the spindle 4 when the workpiece W is attached to the spindle 4 and the spindle 4 is rotated, the vibration can be considered to be caused only by the unbalance of the workpiece W. Therefore, if the vibration of the object to be detected 14 is detected by the vibration detector 18 and the vibration display device 19 is operated based on the detection signal, the unbalance of the workpiece W can be accurately displayed numerically.

Moreover, the static pressure acts between the detected object 14 and the small diameter shaft portion 12 of the spindle 4, and between the sliding portion 17 of the detected object 14 and the sliding hole 16 of the frame 1. Therefore, the vibration of the spindle 4 due to the unbalance of the workpiece W is transmitted to the detected object 14 with high responsiveness, and the sliding portion 17 of the detected object 14 is
Vibration in the linear direction is detected by the vibration detector 18. Therefore, unlike the case where the vibration of the rotating portion of the spindle 4 is directly detected, the unbalance of the workpiece W can be accurately detected even if the vibration detector 18 with relatively low accuracy is used.

Further, the first and second oil pockets 21,
If the pressure of the pressure oil 22 supplied to the sensor 23 is set high, when the work W is severely unbalanced, the amplitude of the spindle 4 and the detected object 14 can be suppressed within a narrow range, and the amplitude can be detected by the vibration detector 18. can be accurately detected within a predetermined detection area. Conversely, when the unbalance of the workpiece W is small, the first and second oil pockets 21 and 23
By setting the static pressure low, the amplitude of the spindle 4 and the detected object 14 can be expanded, and even minute vibrations of the workpiece W can be accurately detected within the predetermined detection area of the vibration detector 18. I can do it. On the other hand, by adjusting the strength of the static pressure, it is possible to accurately detect minute vibrations and severe vibrations of the workpiece W using one vibration detector 18.

It should be noted that this invention is not limited to the configuration of the above-mentioned embodiments, and it is also possible to embody it by arbitrarily changing the shape and structure of each part without departing from the spirit of this invention.

Effects of the invention As detailed above, this invention has the advantage of being able to rotate the spindle with almost no vibration, and accurately detecting the balance of the workpiece regardless of the vibration of the frame of the motor etc. It has a great effect.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a rotational balance detection device showing an embodiment of this invention, and FIG. 2 is a cross-sectional view taken along the line A--A in FIG. In the figure, 1 is a frame, 2 is a bearing hole, 4 is a spindle, 5 is a bearing surface, 10 is a drive motor, 13
1 is a chuck as a mounting part, 14 is an object to be detected, 1
6 is a sliding hole, 17 is a sliding part, 18 is a vibration detector,
19 is a vibration display device, 21 is a first oil pocket, 22 is pressure oil, 23 is a second oil pocket,
24 is a third oil pocket, 25 is a fourth oil pocket, and W is a workpiece.

Claims (1)

[Scope of utility model registration request] A spindle 4 equipped with a mounting portion 13 for integrally rotatably mounting a workpiece W is rotatably supported in a bearing hole 2 of a frame 1, and a bearing surface 5 of this bearing hole 2 has a mounting portion 13 attached thereto for integral rotation. A first static pressure generating section 21 for applying static pressure in orthogonal directions and a second static pressure generating section 23 for applying static pressure along the axis of the spindle 4 are provided. surface 5 and the spindle 4
In addition, the object to be detected 14 detected by the vibration detector 18 is externally fitted in the vicinity of the workpiece W attachment part 13 of the spindle 4 so as to be relatively rotatable. A rotational balance detecting device characterized in that the detection object 14 is provided with a third static pressure generating section 24 that generates static pressure between the detection object 14 and the spindle 4.