US3643925A

US3643925A - Pneumatic vibrator

Info

Publication number: US3643925A
Application number: US855247A
Authority: US
Inventors: Phillipp Uebel
Original assignee: Wacker Werke GmbH and Co KG
Current assignee: Wacker Werke GmbH and Co KG
Priority date: 1968-09-10
Filing date: 1969-09-04
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22
Also published as: CH493283A; FR1587902A; GB1275147A; DE1810313A1; DE6808084U

Abstract

Method and apparatus for compacting concrete and similar masses according to which the medium to be compacted is, by means of a pressure medium, actuated eccentric mass circulated in a tubular housing with circular cross section, subjected to oscillations.

Description

United States Patent Uebel Feb. 22, 1972 [54] PNEUMATIC VIBRATOR 2,778,612 l/l957 Peterson ..259/l R 2,917,290 12/1959 Peterson ..259/1 R [72] -9 3,259,103 7/1966 Buell et a1 ..1 16/137 A 1 AssigneeI YK I1YYSFBEMKQLMPEG22.,QELTEPX 221 Filed: Sept. 4, 1969 Primary Examiner-Walter A. $611661 Assistant Examiner-Philip R. Coe [21] Appl 855247 Att0rneyWalter Becker [30] Foreign Application Priority Data [57] ABSTRACT Sept. 10, France and apparatus for compacting concrete and Similar masses according to which the medium to be compacted is, by Cl 259/1 43 means of a pressure medium, actuated eccentric mass circu- [51] Int. Cl ..B06b l/l8 lated in a'tubular housing with circular cross section, sub- [58] Field of Search ..116/137 A; 74/87; 259/1, DIG. 43 1 to oscillations [56] References cued 3 Claims, 5 Drawing Figures UNITED STATES PATENTS "1""7221'331259 R PATENTEDFEB 22 I972 SHEET 1 BF 2 (.OMP/FESSED HI)? INVENTOR.

PAIENTEBFEB22 I972 3.643 925 sum 2 0r 2 FIG-3 3 PHIL/PP 05511 PNEUMATIC VIBRATOR The present invention relates to a pneumatic vibrator with an unbalanced mass subjected to a flow of air under pressure.

Vibrators of this general type are used for various purposes, in particular for compacting concrete and similar substances. Depending on the type of employment of such vibrators, a distinction is made between inner vibrators and outer vibrators. Inner vibrators are, as the name implies, introduced into the medium to be compacted so that the vibrating device is completely surrounded e.g., by the concrete to be compacted, and the freed energy is directly transmitted to the concrete. Outer vibrators, as the name implies, are from the outside brought against the medium to be compacted, for instance against the sheathing for concrete walls and the like. The freed energy of the outer vibrator is conveyed to the material to be compacted through the intervention of a baseplate or the like and the sheathing. Consequently, the vibrating device is not in direct contact with the material to be compacted.

Vibrators have become known according to which the stationary shaft is provided which is coaxial with a cylindrical housing, and a roller body is placed upon said shaft and forms a hollow cylindrical roller. The inner diameter of the hollow roller is larger than the diameter of the stationary shaft, and the outer diameter of the hollow roller is so dimentioned with regard to its inner diameter that the outer cylinder surface of the roller can never contact the inner wall of the housing.

Furthermore, designs have become known according to which the roller body is journaled on separate roller paths arranged within the stand, said roller body rolling on said paths. The stand and the roller body are with regard to their dimensions so adapted to each other that between the roller body and the cylindrical inner wall there will always remain a narrow airgap.

According to a further heretofore known design, a vibrator has been suggested in which the movable cylinder has an unbalanced mass which is adapted to displace the center of gravity of the cross section of the cylinder with regard to the geometric center of said circular cross section in the direction toward the cylindrical running surface. Compressed air operable vibrators have become known which have a cylinder with a three-arc trochoid contour and comprising end walls with passages for guiding compressed air while furthermore being equipped with a rotary body having the shape of an elliptic cylinder in which one of the cylinder end faces is provided with an axial compressed air feeding passage and three air discharge passages. The rotary body has two axial passages with subpassages leading to different mantle surfaces.

There has also become known a compressed air operated oscillation producing device with an inner ring having an inner path for a ball which represents the oscillating mass, said ball being rotated on said path by compressed air, while a running path ring forms a single element and the compressed air is fed through tangential nozzles of a head arranged in the center of the ring.

Finally there have become known vibrators in which a ball rolls on a circular running path while for purposes of increasing the air velocity a Venturi tube is provided at the air inlet.

All of the above-mentioned designs of vibrators, inner as well as outer vibrators, have a fixed housing in which the eccentric mass rolls on a circular path or about a fixed shaft. The elements which are subjected to wear are, in order to extend their life, hardened and ground. Furthermore, these vibrators comprise many individual elements which are difficult and expensive to produce and machine so that these known devices are relatively expensive. The running paths, especially with ball vibrators, are bound to a circular shape since with other path designs the airflow will detach itself from the path so that these devices cannot properly operate. With these known devices a purely kinetic energy is produced, for instance, by a rolling ball. An alternating effect of kinetic energy and potential energy for increasing the output of the device is not possible.

It is, therefore, an object of the present invention to provide a vibrator which will overcome the above-mentioned drawbacks.

It is a further object of this invention to provide a device which will make it possible, while employing simple means, to increase the output of vibrators and to permit a more economic production thereof.

These and other objects and advantages of the invention will appear more clearly from the following specification in connection with the accompanying drawings, in which:

FIG. 1 illustrates a section through a vibrator according to the present invention.

FIG. 2 represents a possibility of combining a plurality of vibrators according to the invention.

FIGS. 3, 4 and 5 illustrate further modifications of a vibrator according to the present invention.

The method according to the present invention is characterized primarily in that the medium to be compressed is subjected to oscillations by means of an eccentric mass which is accelerated by means of a pressure medium in a tubular housing of any desired shape and circular cross section.

The method according to the present invention may be carried out by a device which is characterized in that one or more balls are employed as unbalanced mass, and that the said balls are subjected to compressed air in a tubular housing of circular cross section and of any desired shape.

According to a further feature of the invention the housing is provided with a compressed air inlet and a compressed air outlet.

Referring now to the drawings in detail, the arrangement shown in FIG. 1 illustrates a tubular housing I having a circular cross section. Housing 1 has a compressed air inlet 2 adapted to be connected to a source of compressed air, and outlet openings 3. One or more balls 4 are provided in the tubular housing 1.

In view of the compressed air introduced into the housing 1, air will accumulate ahead of the ball 4 the diameter of which is slightly less than the inner diameter of the tubular housing and will cause the ball 4 to roll in the housin g l. The frequency at which the ball 4 will roll in the housing I is dependent on the air pressure and thus can be varied in conformity with the air pressure. As soon as the ball 4 has passed by the outlet openings 3, compressed air behind said ball escapes through said openings 3. The inertia of the ball, however, suffices to move the ball past the compressed air inlet 2 whereupon the ball 4 is again subjected to the effect of the compressed air as described above.

FIG. 2 illustrates a possibility of mounting a plurality of vibrators according to the invention on a baseplate 5 to form an outer vibrator so as to obtain a certain centrifugal force. In this instance, the kinetic energy of the vibrator is through baseplate 5 conveyed to the material to be compacted.

While the housing of the vibrator according-to the present invention and as shown in FIGS. 1 and 2 is of circular shape, it is, of course, also possible to vary the shape of the housing. Thus, FIG. 3 shows a housing of an oval shape with a loop at the bottom. According to FIG. 4 the housing has a somewhat triangular shape with a coil interposed at the wider side. FIG. 5 shows the housing in the form of a coil with the ends interconnected by an S-shaped pipe. While FIGS. 1 to 4 show only one compressed air inlet with an adjacent group of outlets, also more than one compressed air inlet and one group of outlets may be provided as indicated in FIG. 5.

As will be evident from the above, by employing a simple pipe as running path and housing, an extremely simple and low-cost production of such vibrator will be possible. By the arrangement of difi'erent curves of the housing it will be appreciated that, when operating a vibrator of such design, frequency leaps and acceleration leaps will be obtained which, when employing an inner vibrator, for instance, for compacting, for instance, concrete, have an extremely favorable effect upon the material to be compacted. Moreover, the generation, for instance, when the housing is in the form of a helical coil, is

effected in different planes which likewise has a very advantageous effect in connection with the compacting of concrete.

With the vibrator according to the present invention it is possible, in view of the curves of the housing, which may follow each other in a desired manner, to assure an alternate conversion from kinetic energy to potential energy and vice versa. This greatly contributes to an improvement of the output of a device according to the invention.

The design of the vibrator according to the invention can at any time be adapted to the specific conditions of employment inasmuch as any desired shape, for instance, that of a circle, a helical coil, a safety pin, etc., can easily be produced,

The arrangement of the vibrator according to the present invention makes it possible to design the vibrator as a portable implement inasmuch as it can easily be combined with compressed air bottles so that such vibrator can also be employed in areas which are normally not easily reached, as for instance high mountains.

Thus, while only one ball 4 is shown in the drawing, two or more balls 4 may be employed.

It is, of course, to be understood that the present invention is, by no means, limited to the particular constructions shown in the drawings but also comprises any modifications within the scope of the appended claims.

What I claim is:

l. A vibrator for compacting material, especially concrete, which includes: tubular housing means defining a path closed in itself and having a substantially circular cross section, ball means rotatably arranged within said housing means and adapted for circulating around inside said housing means, and means associated with said housing means and connectable to a source of air pressure effective for circulating said ball means in said housing means, said housing means being of an oblong shape and including a coiled section at one end portion thereof.

2. A vibrator for compacting material especially concrete, which includes: tubular housing means defining a path closed in itself and having a substantially circular cross section, ball means rotatably arranged within said housing means and adapted for circulating around inside said housing means, and means associated with said housing means and connectable to a source of air pressure effective for circulating said ball means in said housing means, said housing means having the form of an equilateral triangle with coil means forming the basis of said triangle.

3. A vibrator for compacting material, especially concrete, which includes: tubular housing means defining a path closed in itself and having a substantially circular cross section, ball means rotatably arranged within said housing means and adapted for circulating around inside said housing means, and means associated with said housing means and connectable to a source of air pressure effective for circulating said ball means in said housing means, said housing means having the form of a coil having its ends interconnected by a flat S-shaped tubular section.

Claims

1. A vibrator for compacting material, especially concrete, which includes: tubular housing means defining a path closed in itself and having a substantially circular cross section, ball means rotatably arranged within said housing means and adapted for circulating around inside said housing means, and means associated with said housing means and connectable to a source of air pressure effective for circulating said ball means in said housing means, said housing means being of an oblong shape and including a coiled section at one end portion thereof.