JPS6049745B2 - vibrator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vibrator used for uniformly compacting concrete in concrete placing work and the like.

A conventional vibrator of this type, as shown in Fig. 1,
A flexible shaft 3 is built in a flexible tube 1 that is connected to a prime mover (not shown) and a vibrating cylinder 2, and has one end connected to the prime mover and the other end to a flexible joint 4, and via the flexible joint 4, The power of the prime mover is transmitted to a rotating shaft 5 built in the vibrating cylinder 2.

One end of this rotating shaft 5 is connected to the flexible joint 4, and
It is supported by a self-aligning bearing 6, and a rolling portion 7 is formed at the other end. This rolling part 7 has a part cut out, so when the rotating shaft 5 rotates, centrifugal force acts in the opposite direction to the notched part of the rolling part 7, and the rotating shaft 5 is rotated by the self-aligning bearing 6.
Due to the self-aligning action of It comes into contact with the provided rolling surface 9. Then, as shown in FIG. 2, a frictional force F acts on the contact portion. Now, rotation axis 5
Assuming that is rotating counterclockwise, the rolling portion 7 also rotates counterclockwise, and the frictional force F acts on the rolling portion 7 in a clockwise direction. Because of this frictional force F, the center s of the rolling part 7
, a moment that tries to reduce the rotation of the rolling part 7,
A force acts to swing the rolling portion 7 clockwise around the center o of the rolling surface 9 on the inner surface of the tip fitting 8, and the rolling portion 7 rotates counterclockwise with respect to the rotational direction of the rotating shaft 5. As a result, a whirling motion occurs in the vibrating cylinder 2, which generates vibrations at a frequency higher than the rotational speed of the rotating shaft 5. The frequency of vibration of the vibrating tube 2 can be calculated from the following formula (see FIG. 2).
N=n×- ・・・・・・ (1) Here, N ■ Frequency of vibration tube 2, n ■ Number of rotations of rotating shaft 5, d ■ Outer diameter of rolling part 7, D ■ Rolling surface It has an inner diameter of 9.

However, the self-aligning bearing 6 is not designed to be suitable for the large whirling motion of the rotating shaft 5, and when the rotating shaft 5 makes a large whirling motion, the retainer of the self-aligning bearing 6 becomes too large. This causes the cage to break early.

In addition, if oil or fat adheres to the rolling portion 7 or the rolling surface 9, the frictional force at the contact area between the rolling portion 7 and the rolling surface 9 will decrease, and the vibration of the vibrating tube 2 may become weaker or the vibrating tube 2 may To prevent vibrations from occurring, install an oil seal 10 adjacent to the lower part of the self-aligning bearing 6, and the grease inside the self-aligning bearing 6 may leak downward and cause damage to the rolling parts 7 and rolling surfaces 9. It is designed to prevent it from adhering to the surface. However, if the whirling motion of the rotating shaft 5 is increased, the displacement of the lip of the oil seal 10 in the direction perpendicular to the axis becomes larger than the allowable value, which deteriorates the function of the oil seal and eventually causes it to break. Become. Therefore, in conventional vibrators, in order to prevent damage to the self-aligning bearing 6 and deterioration and damage to the oil seal 10,
The whirling angle of the whirling motion of the rotary shaft 5 must be made as small as possible, and for this purpose, the length of the rotary shaft 5 must be increased or the gap T between the rolling surface 9 and the rolling D-d moving part 7 must be made small. We have to make D-d smaller.

However, when -i- is made smaller, (4)-d) becomes smaller, and the frequency of the vibrating cylinder 2 increases according to the above-mentioned equation (1). However, in general, for concrete compaction, the optimum vibration frequency of the vibrating tube 2 is approximately 12,000 vpm, and if the frequency is higher or lower than this, the effect will be poor.
(D-d) cannot be made too small. Therefore, since the gap between the rolling surface 9 and the rolling portion 7, D-d, cannot be made too small, in order to reduce the whirling angle of the whirling motion of the rotary shaft 5, The length must be made as long as possible, which would increase the length of the vibrating tube 2, increase the weight of the vibrator, and have disadvantages such as making it difficult to handle when used for pouring concrete, etc. .

In view of the above points, the present invention provides a difference between the inner diameter D of the rolling surface and the outer diameter d of the rolling part (D -d) is maintained at a predetermined value, the gap between the rolling surface and the rolling part can be made arbitrarily small, and the rotating shaft can be shortened so that even if the rotating shaft swings around, The present invention provides a vibrator that is lightweight and easy to handle without damaging self-aligning bearings or oil seals.

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

FIG. 3 is a front sectional view of one embodiment of the present invention.

In the figure, the vibrator 14 is composed of a vibrating cylinder 12' and a rotating shaft 15 supported by a bearing 16.

The vibration tube 12 consists of a bearing tube 21, a cover 22 screwed onto the upper end of the bearing tube 12, and a tip fitting 16'' attached to the lower end of the bearing tube 21 and having a rolling surface 19 on its inner surface. The flexible tube 11 is screwed onto the cover 22.
This flexible tube 11 has a built-in flexible shaft 13, one end of which is connected to a prime mover (not shown), and the other end connected to a rotating shaft 15. The rotating shaft 15 is connected to the vibration tube 12
One end is supported in a bearing sleeve 21 by a self-aligning bearing 16, and an oil seal 20 is provided adjacent to the lower part of the self-aligning bearing 16.

Further, a rolling portion 17 is formed at the other end of the rotating shaft 15, facing the rolling surface 19 of the tip metal fitting 16''.
The center line 24 of the rotary shaft 15 is eccentric by e with respect to the center line 23 of the rotating shaft 15. Therefore, if the inner diameter of the rolling surface 19 is D1 and the outer diameter of the rolling portion 17 is d, then the rolling surface
The gap between D-Dl9 and the rolling part 17 is (] "-e", and by arbitrarily selecting e, the gap between the rolling surface 19 and the rolling part 17 can be set to (D-d) to a predetermined value. Since it can be arbitrarily reduced in size while being held, when the rotating shaft 15 swings around, excessive force may act on the self-aligning bearing 16 or oil seal 20, or the lip of the oil seal 20 may exceed the allowable value. The length of the rotating shaft 15 can be arbitrarily shortened so as not to be displaced.

Further, the center line of a portion 25 of the rotating shaft adjacent to the rolling portion 17 of the rotating shaft 15 may be eccentric with respect to the center line 23 of the rotating shaft 15. Then, when the rotating shaft 15 rotates, the centrifugal force acting on the rotating shaft 15 increases, and the rolling portion 1
7 and the rolling surface 19 of the end fitting 16'',
This can be made easier and stronger than when only 7 is eccentric. Since the oil seal 20 is installed adjacent to the lower part of the self-aligning bearing 16, the grease inside the self-aligning bearing 16 flows downward and onto the rolling surface 19 and rolling portion 17. It is designed so that it does not stick to the surface and interfere with the vibration-exciting action. Furthermore, when the vibrator 14 is started, the rolling portion 17 contacts the rolling surface 19 with an impact, and due to the reaction, the rolling portion 17 is largely repelled in the opposite direction, and the self-aligning bearing 16
If there is a possibility that an excessive force may act on the oil seal 20, in order to limit the movement of the rolling portion 17, a portion of the rotating shaft 15 that is not eccentric near the self-aligning bearing 16,
For example, the restriction portion 18 may be provided inside the bearing sleeve 21 opposite to the portion of the rotating shaft 15 below the oil seal 20.

This restricting portion 18 also causes the rolling portion 17 and the rolling surface 19 to wear out when the vibrator 14 is used for a long period of time, and the amount of movement of the rolling portion 17 increases. If the angle becomes large, it is possible to prevent excessive force from acting on the self-aligning bearing 16 and the oil seal 20, or to prevent the lip of the oil seal 20 from being displaced beyond an allowable value. Also, instead of the restricting portion 18, a self-aligning bearing 1
6, the limiting portion 18a
may be provided. Next, the action of the vibrator 14 will be explained.

When the prime mover is energized and the flexible shaft 13 rotates, the rotation is transmitted to the rolling portion 17 of the rotating shaft 15. Since the rolling part 17 is eccentric with respect to the rotating shaft 15 by e, centrifugal force is generated in the rolling part 17, and this centrifugal force and the self-aligning bearing 1
Due to the self-aligning action of 6, the rolling portion 17 moves toward the rolling surface 19. In this case, since the center line 24 of the rolling part 17 is eccentric by e with respect to the center line 23 of the rotating shaft 15, the amount of movement of the rolling part 17 toward the rolling surface 19 is small as described above. As a result, the whirling angle of the rotating shaft 15 becomes smaller,
The rolling portion 17 rolls on the rolling surface 19 without excessive force acting on the self-aligning bearing 16 and the oil seal 20, and the rotating shaft 15 performs whirling motion around the self-aligning bearing 16. . In this case, the inner diameter D of the rolling surface 19 and the rolling portion 1
Since the difference (D-d) in the outer diameter d of the vibrator 14 is maintained at a predetermined value, the vibrating cylinder 12 of the vibrator 14 has the above-mentioned (1
) Vibrations of a predetermined frequency are generated by the equation. As described above, the present invention arbitrarily selects the eccentricity e between the center line of the rotating shaft and the center line of the rolling part, thereby preventing excessive deviation or displacement of the self-aligning bearing and oil seal. , the length of the rotating shaft can be arbitrarily shortened. Further, if necessary, the centrifugal force can be increased by making the center line of a part of the rotating shaft adjacent to the rolling portion of the rotating shaft eccentric with respect to the center line of the rotating shaft. In addition, by providing a restricting part, the whirling angle of the rotating shaft can be reduced even when the vibrator is started or when the rotating part of the rotating shaft and the rolling surface of the vibrating tube are worn out, so self-aligning can be achieved. The rolling part of the rotary shaft rolls on the rolling surface of the vibrating tube to generate vibration at a predetermined frequency in the vibrating tube of the vibrator without causing excessive stress or displacement in the bearing or oil seal. Can be done. Therefore, the vibrating tube can be shortened, and a vibrator that is small, lightweight, and easy to handle can be provided.
It has great industrial effects, such as making concrete pouring work easier.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view of a conventional vibrator, FIG. 2 is a sectional view taken along the line AA in FIG. 1, and FIG. 3 is a front sectional view of an embodiment of the present invention. 12... Vibration tube, 13... Flexible shaft, 14...
... Vibrator, 15 ... Rotating shaft, 1
6...Self-aligning bearing, 16''...Tip fitting, 17...Rolling part, 18, 18a...
・・Restriction part, 19 ・・Rolling surface, 20 ・・・
Oil seal, 21... Bearing tube, 22...
・Cover, 23... Center line of rotating shaft 15, 24.
. . . Center line of rolling portion 17, 25 . . . Part of rotating shaft 15.

Claims (1)

[Scope of Claims] 1. A vibrating tube to which a tip metal fitting having a rolling surface on its inner surface is attached, and a vibrating tube that is built in the vibrating tube and supported by a bearing, and a vibrating tube that has a tip that is mounted on the rolling surface of the tip fitting. 1. A vibrator comprising a rotating shaft on which a rolling part is formed, the center line of the rolling part being eccentric with respect to the center line of the rotating shaft. 2. A vibrating tube to which a tip fitting with a rolling surface provided on its inner surface is attached, and a rolling section that is built into the vibrating tube, is supported by a bearing, and rolls on the rolling surface of the tip fitting at its tip. , and a limiting portion provided on a vibrating cylinder opposite to the rotating shaft in the vicinity of the bearing that supports the rotating shaft, the center line of the rolling portion being aligned with the center line of the rotating shaft. A vibrator characterized by being eccentric with respect to the center line.