JP3006153B2 - Vibrating drum - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vibrating drum suitable for use in, for example, mixing, drying and cooling of bulk materials, and particularly suitable for separating sand from castings.

[0002]

2. Description of the Related Art FIGS. 8 and 9 show a conventional vibrating drum used for separating sand from castings. In FIG. A drive unit mounting frame 72 is fixed to a support base 75 via a driving spring 74 for resonance on the side of the drum main body 71, and the support base 75 is connected to the drum main body 71 via a plurality of mounting ribs 86. It is fixed to.

A supply port 85 for supplying a casting to be sanded is provided at the left end of the drum body 71 in FIG. 8, and a discharge port for discharging the sanded casting is provided at the right end. An outlet 84 is formed. Drum body 7
Both sides of 1 are closed by end walls 82a and 82b.

[0004] The entire drum body 71 is made up of vibration isolating springs 76a, 7a.
6b, 77a, and 77b support the ground E so that it can vibrate. A vibrating unit 73 including a pair of vibration motors 79a and 79b as a driving unit is fixed to the frame 72. The vibrating motors 79a and 79b are configured in a known manner, but have substantially semicircular unbalanced weights 80a and 80b fixed to their rotating shafts 81a and 81b. 72
But the unbalance weights 80a, 80
b is fixed to the rotation shafts 81a and 81b with the same rotation phase. A dust collecting duct 78 is provided on the upper wall of the drum body 71.
Is fixed, and communicates with the inner space 87 so as to guide dust generated due to sand separation of the casting in the drum main body 71 to the outside as described later. The entire vibration drum 70 is inclined several degrees downward toward the discharge port 84.

[0005] The vibration drum 70 of the conventional example is configured as described above. When the vibrating section 73 is driven, the vibration motors 79a and 79b rotate synchronously. The pair of vibration motors 79a and 79b are driven to rotate at a frequency close to the resonance frequency determined by the constant, the mass of the entire drum body 71, the mass of the vibrating section 73, and the like. This rotation generates a linear vibration force in the direction in which the spring 74 extends, and this is transmitted to the drum main body 71 via the spring 74 and the mounting rib 86. Since the drum body 71 is supported by the vibration-proof springs 76a, 76b, 77a, and 77b so as to be able to vibrate, the drum body 71 vibrates in a diagonal direction in the direction indicated by the arrow. Perform a circulating motion as indicated by the arrows. Since the drum body 71 is inclined downward by several degrees toward the discharge port 84, the sand S and the casting M move toward the discharge port 84 together with the circulating motion indicated by the arrow in FIG. In this process, sand is separated, and the separated casting M and sand S are separated and discharged from the discharge port 84.

The conventional vibrating drum 70 has the above-described structure and operates. However, other types of casting-type sand removers, for example, for supplying a casting to be sanded to a scaly floor. Then, the separated sand is discharged downward by linear vibration, and the sand is transferred over the floor by linear vibration.However, in this type of casting sand remover, impact is applied to the casting. Therefore, there is a disadvantage that the sand does not fall off depending on the shape of the casting because there is not much change in the posture (reversal, etc.) of the casting. Is removed, but a pair of vibration motors 79
a and 79b are not always synchronized, and when they are out of synchronization, an irregular vibration force is applied to the drum main body 71, so that the above-described operation is not performed and sufficient sanding cannot be performed. Of course, it will have the same disadvantages as the other types of sand removers described above. For example, the casting M may be damaged. In order to cope with this, strict setting standards are required for the mounting positions of the vibration motors 79a, 79b with respect to the drum main body 71 and the arrangement of the springs 74 so that the vibration motors 79a, 79b rotate synchronously. Therefore, not only is the vibration drum 70 shown in FIGS. 8 and 9 expensive, but also a resonance state can be obtained depending on the total weight and the mass distribution of the casting M and the sand S to be sanded in the drum main body 71. In some cases, synchronous rotation cannot be performed.

[0007] As another type of casting sand remover, there is a so-called rotary drum in which a drum is rotated at a predetermined speed in a fixed direction. When the sand is separated, the casting is lifted by scratching. When it is hit, it goes to a certain height and falls, and this impact may damage it. In addition, since the contact time with the casting is long, the sand and the additives are aged. Further, as described above, noises are generated because drops due to scratching or the like occur periodically. Although this conventional example is excellent for such difficulties, it still has the points to be improved as described above.

FIGS. 10 and 11 show other conventional examples. The parts corresponding to the above-mentioned conventional examples are denoted by the same reference numerals, and the detailed description thereof will be omitted. That is, in the conventional example, the vibration mechanism 73 for generating the linear vibration force is attached to the peripheral wall portion of the drum main body 71 as described above, and this is a pair of vibration motors 82A and 82A.
2B, which are fixed to the mounting base 95
I have. Gears 89a and 89b of the same diameter and the same number are fixed to one end of each of the rotating shafts 83a and 83b, and the gears 90a and 90b of the same diameter and the same number are fixed to the bearing housing 88 '. The shaft is rotatably mounted . By the vibration motors 82A and 82B is that the AC power supply to each of the power cord 1 85, 1 85 are connected, although being driven respectively opposite directions, they gears 90a, 90b meshing and large-diameter gear The drive shafts 83a, 83b are meshed with 89a, 89b.
The semi-circular unbalance weights 84a and 84b fixed to one end of the motor 1 rotate synchronously at the same speed in opposite directions. As a result, a linear vibration force is generated in the X direction as shown in FIG.

The other conventional example has a simpler structure than the above conventional example, but has the following disadvantages.

Also in this conventional example, the drum main body 71 has a cylindrical shape, and the casting that separates sand is transferred along the axis C of the drum main body.
a and 77b, and also in this conventional example, a vibrator 73 also composed of two vibrating motors 82A and 82B.
Is attached to the peripheral wall of the drum main body 71.

In this conventional example, each of the vibration motors 82A, 82B
Semi-circular unbalance weights 84a, 84b are fixed to the drive shafts 83a, 83b, respectively.
A gear having the same shape and the same number of teeth is fixed to one end of 83b, and these gears mesh with each other, so that the two vibration motors 82A and 82B rotate at the same speed in synchronization with different directions. . As a result, as shown in FIG. 12, a linear vibration force is generated in the direction of arrow P, which crosses the axis C almost at right angles. Thus, when the casting to be sanded has not yet been introduced into the drum main body 71, that is, when there is no load, each point on the peripheral wall of the drum main body 71 performs a linear vibration as indicated by an arrow. However, this direction is substantially parallel to the direction of the linear vibration force P, and is substantially equal to the angle α with respect to the horizontal line to which the vibration mechanism 73 is attached. That is, when there is no load, the drum vibrates at substantially uniform amplitude and vibration angle at each point of the peripheral wall portion of the drum main body 71. It is conceivable to perform a circulating motion as shown by an arrow R in FIG. Therefore, in practice, it is difficult to perform the circulating motion as shown in the figure, and the oscillating speed is small because the amplitude is small, and the fluidity is inferior to that of the conventional example. This is because the casting M to be sanded is driven to vibrate together with the drum body 71 in the direction of the vibration P at no load, and at the bottom wall of the drum body 71, a ₁
The vibration direction is almost equal to the direction of P as shown by
Thus is substantially parallel to the direction of P as described above in which from the angular position a ₂ in the no-load of 45 degrees counterclockwise, the angle of the vibration relative to the inner circumferential wall surface of the drum body 71 at this point, Approximately parallel, and therefore, as is evident from vibration theory, 1 g
The following accelerations do not make a jumping movement, and therefore have no transfer action by vibration. Furthermore, from the counterclockwise direction which, in a larger angular position, for example the inner wall surface of the transfer action drum body 71 by vibration on the inner wall surface of the drum body 71 relative to the at point a _3, since the transfer of the counterclockwise direction is desirable However, in the clockwise direction, which is opposed to the transfer force in the counterclockwise direction from the lowermost point a ₁ , the casting M in the drum main body and the sand S that has been separated from the drum main body are moved around the inner circumference of the drum main body 71. By pressing the wall surface, it vibrates integrally as if it were an integral rigid body. Therefore, the amplitude at each point by the fixed exciter 73 is naturally small, and thus fluidization is prevented as described above.

Further, in this conventional example, for example, 60H
z, 894r. p. m. , But 89
4r. p. m. Belongs to the very low frequency in the technical field of so-called vibration, which causes the building near the place where this vibrating drum is disposed to be in resonance with the vibration due to this very low frequency, and a part of the building, for example, a shoji or a door, etc. Is vibrating rattling. Therefore, residents living near the factory where the vibrating drum is provided suffer from vibration pollution. Further, FIG.
In the prior art, since the gears are fixed to one ends of the drive shafts 83a and 83b, they rotate while meshing with each other. However, no matter how precisely this meshing is designed, this meshing noise can be zero. No, it belongs to the treble, and this noise adds to the noise of nearby residents.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problem, and has a small settling when the load is changed from no load to a load even with the same rotational driving force. When a casting material to be sanded, for example, is injected, a vibrating drum capable of promoting fluidization of the casting and also preventing extremely low frequency pollution to a nearby building and also preventing noise pollution. The purpose is to provide.

[0014]

SUMMARY OF THE INVENTION It is an object of the present invention to generate a circular excitation force on a peripheral wall of a drum body supported on the ground by an anti-vibration spring by generating a circular excitation force by rotation of an unbalanced weight. The machine is directly attached so that the angle formed by a straight line vertically connecting the center of the circular excitation force and the axis of the drum body with respect to the horizontal line is 0 to 90 degrees above the axis. This is achieved by a vibrating drum.

[0015]

The circular vibrating force generator has a straight line connecting the center of the vibrating force and the axis of the drum body vertically with respect to a horizontal line at 0 degree or less.
Directly on the peripheral wall of the drum body so as to form an angle of 90 degrees ,
Since it is fixed, the peripheral wall of the drum body performs an elliptical vibration at each point, especially when the drum is mounted so as to be at 20 to 30 degrees. Vibrates in the same direction as the fixed angle of the circular excitation generator against the inner peripheral wall of the main body,
Further, as the angular position is advanced clockwise or counterclockwise in the drum, the amplitude also increases in the direction perpendicular to the straight line, that is, in the short axis direction, and the short axis ratio of the elliptical vibration increases. Thereby, for example, the casting which is put into the drum body, for example, the casting to be sanded is efficiently circulated, but even if the circular exciting force is constant under no load and in the loaded state, the change in the amplitude, that is, There is almost no "fall",
The fluidity of the casting is greatly increased than before. This is because the settling of the amplitude at each point is small, but in the short axis direction of the elliptical vibration, at each point on the inner wall of the drum body,
Since it has a component perpendicular to its tangential direction, it receives a certain acceleration in this direction, so that the drum main body and the casting to be sanded into it as in the past are integrated as if by a drum. There is no vibration phenomenon that increases the mass of the casting, and the casting to be sanded receives a jumping force from each point on the peripheral wall of the drum body, and also receives a transfer force in the major axis direction of the elliptical vibration, and its circulation speed Can be much larger than before. Therefore, the casting to be sanded circulates in the same manner as in the prior art, but the circulation speed is high and the castings circulate at a uniform speed over the entire area. Therefore, although the casting is hot, the chance of contact with the separated sand increases, that is, heat exchange can be performed efficiently, and since the casting to be separated contains moisture, this is the heat. The latent heat is taken off when evaporated by the exchange, and is effectively cooled, and the sanded casting is cooled and discharged from one end of the drum body.

Further, according to the vibrating drum of the present invention, it is possible to greatly reduce the extremely low frequency pollution to the neighboring buildings. In this case, elliptical vibration is performed at each point of the drum body. When this short-axis component is viewed from a distance, the vibration with respect to the projection surface becomes a main source of noise. The amplitude is small because of the vibration of the amplitude in the short axis direction. In the conventional vibrating drum, since linear vibration is performed at each point on the peripheral wall portion of the drum body with a substantially constant amplitude, the vector is aligned in this direction, and the projection surface vibrates with a large amplitude. It causes extremely low frequency pollution.

Further, according to the present invention, since a circular exciting force is generated, no gear that meshes with each other is used as in the conventional example shown in FIG. 11, so that no noise pollution occurs.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A vibration drum according to an embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 to 5 show this embodiment. In the drawings, the vibration drum is indicated as 1 as a whole, and a vibrator 3 according to the present invention is provided on one side of a peripheral wall of a drum body 2. I have. The drum main body 2 is supported by vibration-proof springs 6a, 6b, 7a, and 7b disposed on the columns 4a, 4b, 5a, and 5b so that the drum main body 2 can be vibrated at an angle of several degrees downward in the drawing. In FIG. 1 of the drum body 2, a supply port 8 for supplying a casting to be sanded is formed at the left end, and a discharge port 9 for discharging the sanded casting is provided at the right end. ing.

The drum body 2 has ribs 1 on its peripheral wall.
The right end is partially closed by a lid 11.

Next, the details of the vibrator 3 will be described with particular reference to FIGS.

The vibrator 3 according to the present invention is a circular vibrator that generates a circular vibration force, and an electric motor 24 is fixed on a gantry 23 disposed on the side of the drum body 2. It is a driving source. A first shaft coupled to a universal joint mechanism at both ends of a rotating shaft 24a of the electric motor 24
Link 25 is connected. That first supporting and rotating shaft 24a of the electric motor 24 is coupled to the first link 25 through a universal joint 26 b, also left <br/> end of the first support shaft 25 via a universal joint 26 a It is connected to a shaft 29. The first support shaft 29 is fitted to inner races of a pair of bearings 28a and 28b fixed to both sides of a mounting plate 27 attached to the drum main body 2, and one end of the first support shaft 29 is substantially fixed as shown in FIG. A semicircular unbalance weight 30a is fixed, and the first
An unbalance weight 30b having the same shape as the unbalance weight 30a is fixed to the other end of the support shaft 29.

The first support shaft 29 is further connected with a second link 31 and a second support shaft 35 via universal joints 32a and 32b, which are connected to a mounting plate 33 mounted on the peripheral wall of the drum body 2. An unbalanced weight 36 having the same shape as the unbalanced weights 30a, 30b is fitted at both ends of the inner race of a pair of bearings 34a, 34b provided on both sides.
a and 36b are fixed.

According to the present invention, the center of the circular exciting force, that is, the straight line LL which is perpendicularly connected to the first link 25 and the axis C of the drum body 2 is an angle β with respect to the horizontal line HH. Is set to 25 degrees. The height position of the gantry 23 and the shape of the mounting plate 27 are set so as to obtain this angle of 25 degrees. Furthermore, the first phosphorus according to the present example
The motor 24 that drives the motor 25 is driven so as to rotate clockwise in FIG.

The vibrator 3 according to the present invention is constructed as described above, but a pair of inspection windows 2 are further provided on the upper wall of the drum body 2.
1a and 21b are provided, and an arc-shaped dam plate 22 is fixed to a part of the inner wall near the discharge port 9 of the drum body 2 as shown in FIG.

The vibration drum main body 1 according to the embodiment of the present invention is configured as described above. Next, this operation will be described.

Although not shown, it is assumed that a casting to be sanded is fed from the material supply port 8. When the electric motor 24 is driven, the rotational force of the rotating shaft 24a drives the pair of unbalanced weights 30a and 30b to rotate via the universal joints 26a and 26b and the first link 25,
Further, the first support shaft 29 and the universal joint 32, which fix the unbalance weights 30a and 30b,
a, 32b, an unbalanced weight 36 fixed to both ends of a second support shaft 35 connected via the second link 31
a and 36b are similarly driven to rotate. Note unbalanced weight 30a, the rotation of 30b, 36 a, 36 b, the centrifugal force about the axis of its rotation axis or shaft 29, 35, i.e. although the circular exciting force is generated,
The drum main body 2 vibrates due to the excitation force in a mode to be described later. The rotating shaft 24a of the motor 24 is connected to the unbalance weight 3 via universal joints 26a and 26b.
0a, 30b, and the first support shaft 29 is connected to the unbalance weights 36a, 36b via universal joints 32a, 32b, so that the vibration of the drum body 2 is almost transmitted to the electric motor 24. Rotation driving can be stably continued without being performed.

FIG. 5 shows the relationship between the axis C of the drum main body 2, the center of gravity G of the entire drum, and the center P of the above-mentioned vibrating force of the vibrator 3. A circular exciting force F as shown in FIG. 5 is generated. A rotational moment is generated around the circular exciting force F and the center of gravity G, and the drum main body 2 is moved in accordance with the distance from the center P of the exciting force F. Is indicated by a circle as a line, and a vibration mode as shown is performed on this circumference. I.e. the closest drum body 2 of the peripheral wall portion on the vibrator 3 is performed elliptic vibration as shown by _{a 1, a 2, a 3} , a 4, its major and minor axes other peripheral wall portion And its major axis is sequentially inclined in a counterclockwise direction from a substantially vertical direction. The bottom wall of the drum body 2 performs linear vibration and elliptical vibration as indicated by b ₁ , b ₂ , b _3, and b ₄ , but its major axis is tangential to the inner wall surface of the drum and is counterclockwise. It is inclined to have a vibration transfer force in the direction.

[0029] Furthermore, in a point near the top of the vibrating drum body 2, as shown by _{d 1, d 2, d 3} ····, but of performing elliptical vibration, the major and minor axes are sequentially The vibrations b ₂ , b ₃ , b ₄ , c ₁ , c _2.
.. is an elliptical vibration rotating clockwise in FIG. The vibrations d ₁ , d ₂ , and d ₃ are also elliptical vibrations, and are vibrations that rotate clockwise, but the direction of the long axis is almost parallel to the tangent to each point on the peripheral wall surface of the drum body 2, and The transfer force due to the vibration is such that the material does not rise to this point, but hardly. And in FIG.
About 1 as viewed from the vibration a ₁ relates axis C in the counter-clockwise direction
At an angle position of 70 degrees, linear vibration is performed as indicated by vibration e. From this angular position, the elliptical vibrations f ₁ , f ₂ ,
f _3, f ₄ is, its major and minor axes are for successively increasing a rotation in the counterclockwise direction, again linear vibration b ₁ becomes the lowest portion of the vibrating drum body 2, counterclockwise from the angular position The elliptical vibration is performed again in the direction as described above, but the rotation direction is clockwise.

In the above vibration mode, the origin of the XY rectangular coordinates is the same as the center C '(axis C) of the drum cross-section circle, and the results of calculation by a computer when each dimension is as follows: It is.

Drum diameter D (CM) 120.0 Total weight W (Kg) 1970.0 Moment of inertia AI (KgSqCM) 8820000.0 around the entire center of gravity Total weight center position X coordinate XM (CM) 18.3 Total weight center Position Y coordinate YM (CM) 7.6 Exciting force position X coordinate S (CM) 92.4 Exciting force position Y coordinate SS (CM) 38.3 Frequency N (RPM) 900.0 Lower end amplitude AT (mm) 9.0 Exciting force F (Kg) 5664.7

The casting M supplied from the material supply port 8 is tilted downward by about 2 to 3 degrees in FIG. 1 while receiving the above-described vibration from the inner wall of the drum body 2 so that the casting M moves to the right. During the transfer, the casting M receives a force rising in the counterclockwise direction in FIG. 5 along the inner peripheral wall surface of the drum main body 2 as shown in FIG. Becomes larger and the casting M moves downward.
Is moved down to the right in FIG. 1 while performing the movement shown by the trajectory Q receiving the ascending force again along the inner peripheral wall surface while receiving the sufficient agitation force. In the example, the sand is separated and the cooling action is applied to discharge from the outlet 9 to the outside. As shown in FIG. 3, an arc-shaped weir plate 22 is formed near the outlet 9 along the inner peripheral wall surface. Since it is provided, it can be sufficiently sanded to receive the above-described stirring force and discharged from the discharge port 9 to the outside. If there is no weir plate 22 and the filling rate of the casting M to be sanded into the drum body 2 is small, the drum body 2 will be discharged to the outside from the discharge port 9 without receiving a sufficient stirring force. Therefore, the effect of the weir plate 22 is significant when the filling rate of the casting in the drum body 2 is reduced.

As described above, the casting M to be sanded is introduced into the vibrating drum body 2 and is subjected to the stirring action. The vibrations b ₁ , b ₂ , b ₃ , b ₄ , c ₁ , c ₂ ...
Represents a state in which the casting M to be sanded is not put into the drum main body 2, that is, a vibration state in a no-load state, but a casting to be sanded at a filling rate as shown in the figure. In the case where M is supplied and the circulating motion is performed as shown in the figure, the amplitude of the amplitude is almost smaller than before, and the above-described b ₁ , b ₂ , b _3.
There is almost no change in the vibration mode, and the amplitude is only slightly smaller. Therefore, the casting M receives a transfer force as described below.

[0034] While in the lowest portion of the drum body 2 is performed the linear vibration b _1, with respect to the tangent at the point of the peripheral wall surface of the main body 2 in this respect, it has a right upward direction line, known As described above, such a linear vibration receives a large transfer force. Therefore, the casting M to be sanded on this
Receives a large transfer force and is transferred counterclockwise in the figure. Further, in b ₂ , b ₃ , and b ₄ in the counterclockwise direction, the amplitude in the long axis and the short axis increases. The direction of the major axis is the tangential direction at one point on the peripheral wall of the drum body,
Since the casting M and the sand S also receive a large transfer force at these points and receive a force transferred in a counterclockwise direction, they have a vibration angle at which they receive a transfer force due to vibration. Further, c ₁ ,
In c _2, c _3, the direction of the long axis you to each point of the peripheral wall
Has only a slight vibration angle with respect to the tangent line at which the transfer speed is very small due to the vibration force along the surface. To give a transfer force in the counterclockwise direction. And it vibrates at a ₁ at a position rotated about 90 degrees counterclockwise from the bottom,
At this point, the major axis is substantially parallel to the tangent at one point on the peripheral wall and does not receive any transfer force due to vibration. Vibrations a ₂ , a ₃ , a ₄ at angular positions further advanced in the counterclockwise direction
, The vibration angle of the direction of the long axis with respect to the tangent to each point on the peripheral wall surface is reversed, and the transfer direction is reversed with respect to the above-mentioned vibrations c ₁ , c ₂ , c ₃ . That is, since the casting is transferred in the clockwise direction, if the casting is transferred by such vibration force (actually, the casting falls), the above-mentioned c ₁ , c ₂ ,
reducing the transport speed due to vibration of the c ₃ would become.

As described above, the casting M to be sanded supplied at the filling rate as shown in FIG. 5 receives the stirring force indicated by the arrow Q while receiving the shaft center C of the vibrating drum main body 2.
Is transported to the right in FIG.
Dimensionally, the sand is sufficiently sanded while receiving the spiral stirring power, and the latent heat is released as the moisture from the casting evaporates, so it is cooled efficiently and goes outward from the outlet of the drum body. Is discharged.

In this embodiment, the mode of the elliptical vibration from the bottom of the drum main body to the position rotated by 90 degrees counterclockwise changes as described above. Since this is the direction in which the vibration transfer force is received, and the rotational direction of the elliptical vibration is clockwise, it receives a larger transfer force, and therefore receives the circulation operation efficiently. Further, as described above, according to the present embodiment, the vibration at each point of the peripheral wall portion of the vibration drum main body 2 in the no-load state is changed to the load state, that is, the casting M to be sanded.
, The amplitude, that is, the amplitude of the major axis and the minor axis of the elliptical vibration hardly changes. Therefore, the vibration force is applied to the casting to be sanded in the vibration mode as shown in FIG. You can think of it as being given. It should be noted that there is little sag in the amplitude because of the elliptical vibrations c ₁ , c ₂ , c ₃ , a
₁ In, the vibration angle of the long axis is very small, but the amplitude in the short axis direction is sufficiently large, so that a large acceleration is applied in this direction, and if this is 1 G or more,
As a matter of course, by receiving a jumping force in a direction perpendicular to a tangent at each point on the inner peripheral wall surface, the casting M to be sanded more efficiently receives a stirring force in the drum body. In the conventional example shown in FIG. 10, a linear vibration force is applied to the drum main body 2. On the peripheral wall portion, the linear vibration in the above-described mode is performed, and an angle of 90 degrees in a counterclockwise direction from the bottom is obtained. in position, not only it has small in the direction in which the vibration angle transferring casting, in the angular position in a counterclockwise direction about 45 degrees from the lowest portion, the vibration direction of the linearly reverses, thus the castings in this respect Provides a clockwise transfer force. Therefore, the transfer force in the counterclockwise direction is given at the bottom, and the casting at this point and the casting at about 45 degrees press against each other, resulting in a pressing force against the peripheral wall surface of the drum body.
Therefore, as described above, with respect to the net mass of the drum main body, it becomes as if it vibrates integrally as a rigid body, the effective mass increases, and even if the magnitude of the linear vibration force is the same, there is no load and no load. Then, the amplitude changes greatly. Therefore, in order to obtain the vibration as shown in FIG. 10 under the load, the magnitude of the linear excitation force must be further increased. However, in this embodiment, not only does the amplitude hardly change, but also the driving force can be reduced.

Further, according to this embodiment, the sound level of the very low frequency (900 rpm) noise emitted from the vibration drum 1 is compared with that of the prior art vibration drum to which a linear excitation force shown in FIG. 10 can be applied. Then, an experimental result as shown in FIG. 7 is obtained. That is, the distance from the center of the vibration drum 1 is 1
The relationship between each point up to 00 m and the very low frequency noise level dB at that point changes as shown in FIG. In each case, the noise is reduced linearly, but the noise of the related art is about 6 dB higher. Therefore, since this is the degree in dB, the influence of the ultra-low frequency noise on each building at 100 m can be made much smaller. Obviously, as described above, the conventional vibrating drum performs a linear vibration, and when viewed from a distance as a projection surface, the amplitude of the linear vibration is large, thus causing each damage with ultra-low frequency noise.
According to this embodiment, as shown in FIG. 5, each peripheral wall portion of the vibration drum main body 2 performs an elliptical vibration, and the amplitude in the short axis direction is a noise source with respect to a point at a certain distance from the axis C. Therefore, it is expected that the noise level will obviously be reduced. This is illustrated by FIG.

Further, according to the present embodiment, there is no structure in the circular excitation mechanism that synchronizes the gears by fixing the gears fixed to the two rotating shafts, unlike the prior art. There is no noise due to such gear engagement.
That is, the high-frequency noise is also much higher in the prior art, but becomes "0" in the present embodiment.

FIG. 6 shows a vibrating drum 50 according to a second embodiment of the present invention. Parts corresponding to those of the first embodiment are denoted by the same reference numerals, and a detailed description thereof will be omitted.

That is, according to the present embodiment, one vibration motor 51 is provided on the peripheral wall of the drum main body 2 differently from the first embodiment above the axis C, but the horizontal line H-
It is attached at the same angle to H and in the direction of 25 degrees.
That is, an anti-circular balance weight 53 is fixed to the rotating shaft 52, and the rotating shaft 52 becomes the center of the circular excitation force, and connects this to the axis C of the drum main body 2. The angle β 'formed between the straight line LL and the horizontal line HH is set to 25 degrees as in the first embodiment. It is apparent that the same effect as that of the first embodiment can be obtained in such a structure.
In the present embodiment, in FIG. 6, the rotation direction of the rotary shaft 52 is counterclockwise, thus the circumferential wall of the drum body 2, the rotational direction of the elliptical vibration at each point becomes a counter-clockwise direction, the drum From the bottom of the main body 2, it receives a clockwise transfer force, so that the casting M to be sanded into the drum main body 2 circulates as indicated by Q ′.

Although the embodiments of the present invention have been described above, the present invention is, of course, not limited thereto, and various modifications can be made based on the technical concept of the present invention.

For example, in the above-described first embodiment, the circular exciting force generator 3 is disposed on the right side above the axis in the figure with respect to the axis C of the vibrating drum main body as viewed from the direction opposite to the transfer direction. Although the case has been described, it may be disposed on the upper left side instead. In this case, it is only necessary to dispose the gantry and the mounting in the opposite directions from the positions shown, however, as in the second embodiment, in order to obtain a large transfer force, the rotation of the drive shaft is viewed from the same direction. What is necessary is just to drive an electric motor so that a direction may turn counterclockwise.

In the above embodiment, the angle β formed between the horizontal line HH and the straight line LL connecting the axis C and the center of the circular exciting force perpendicular thereto is 25 degrees. Thus, a substantially larger effect can be obtained even when the angle is larger or smaller, for example, 20 degrees or 30 degrees. However, an angle smaller or larger than 10 degrees, 20 degrees, or 45 degrees can be obtained.
Even if the angle is set to 50 degrees, a greater effect can be obtained than in the prior art.

In the above embodiment, a substantially semi-circular unbalanced weight is rotated around a rotation axis to generate a circular excitation force, or a single known vibration motor is attached, so that a circular excitation is provided. Although a mechanism for generating a vibration force is used, a plurality of vibration motors according to the second embodiment may be connected in series and attached. In this case, the respective rotating shafts may be connected by, for example, a coupling so as to rotate coaxially.

Further, in the present specification, the term "unbalanced weight" is not limited to one having a substantially semicircular shape as shown in the figure, but may have another shape, and may have another structure such as an annular body having a circular cross section. A configuration in which a steel ball is arranged and compressed air is introduced from a part of the tube to rotate the steel ball at a high speed, thereby generating a circular excitation force, is also described in this "Unbalanced weight. ". In addition, any known structure that generates a centrifugal force due to the rotation of the mass and uses this as a circular excitation force is applicable to the present invention.

In the above embodiment, the case where the axis of the drum main body 2 is inclined downward by several degrees with respect to the direction in which the casting is transported has been described. The present invention is applied even if the inclination is upward. That is, in the case of the upward inclination, in FIG. 1, a casting to be sanded is introduced from the left end portion, but the sanding action and the cooling action as described above are sequentially applied because sufficient casting fluidity is added thereto. To the right and discharged outside through the discharge port.

In the above embodiment, no additional device is provided in the vibrating drum main body. However, there is provided a conventionally known vibrating drum, for example, an auxiliary device provided in a vibrating drum applied to sand removal of a casting. For example, a sprinkler may be attached.

In the above embodiment, a circular vibration mechanism is attached to the right above the axis, as viewed from the direction opposite to the transport direction along the axis of the drum main body, so as to rotate clockwise. However, the rotation direction of the electric motor that drives the rotating shaft can be switched at any time, and the casting removed from the mold upstream from the supply port of the vibration drum 1 is shake-outed, for example, by a preliminary shake-out machine, It is supplied to the vibrating drum of the present embodiment, but when the supply capacity of this shakeout machine is divided into large and small,
Alternatively, when the supply speed of the casting to be sanded temporally in one shake-out machine becomes large and small, it is switched in accordance with these, and when the supply speed is small, the rotation direction of the motor is counterclockwise. The direction may be switched in the clockwise direction if the direction is large, so that a smooth continuous casting can be performed.

[0049]

As described above, according to the vibration drum of the present invention, in addition to having a great advantage as compared with the drums of other processing systems as in the case of the conventional vibration drum, the vibrating mechanism is provided in the conventional vibration drum. Not only is it much simpler than this, so that not only can the cost be greatly reduced, but also
Furthermore, very low frequency pollution can be almost eliminated.

[Brief description of the drawings]

FIG. 1 is a side view of a vibration drum according to an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a front view of the same.

FIG. 4 is a partially enlarged front view of the main part.

FIG. 5 is a simplified front view of the vibrating drum for explaining the operation of the embodiment.

FIG. 6 is a sectional view of a vibration drum according to another embodiment.

FIG. 7 is a graph showing a comparison of a very low frequency noise between a conventional vibration drum and the vibration drum of the present invention.

FIG. 8 is a side view of a conventional vibration drum.

9 is a sectional view taken along the line [9]-[9] in FIG.

FIG. 10 is a sectional view of another conventional vibration drum.

FIG. 11 is an enlarged partial cutaway side view of a main part of the conventional example.

FIG. 12 is a schematic cross-sectional view for explaining the operation of the conventional example.

[Explanation of symbols]

 2 Drum main body 3 Exciter 30a Unbalance weight 30b Unbalance weight 36a Unbalance weight 36b Unbalance weight 51 Vibration motor

Continuation of the front page (56) References JP-A-61-150768 (JP, A) JP-A-4-210864 (JP, A) JP-A-3-193262 (JP, A) JP-A-3-189067 (JP) JP-A-53-28860 (JP, A) JP-A-4-220156 (JP, A) JP-A-4-453 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB Name) B22D 29/00 B06B 1/16

Claims (4)

(57) [Claims] 1. A circular vibrating force generator for generating a circular vibrating force by rotating an unbalanced weight directly on a peripheral wall portion of a drum body supported on the ground by a vibration-proof spring. A straight line connecting the center of force and the axis of the drum body vertically is horizontal.
A vibrating drum, wherein an angle formed with respect to a line is set to be 0 to 90 degrees at a position above the axis. 2. When the circular vibrating force generator is located to the right of the axial center when viewed from a direction opposite to the material transfer direction along the axis of the drum body, the circular vibrating force is reduced. 2. The vibrating drum according to claim 1, wherein the rotation direction is clockwise rotation, and when the rotation is on the left side, the rotation direction is counterclockwise. 3. The vibration drum according to claim 1, wherein the angle is 20 degrees to 30 degrees. 4. The vibrating drum according to claim 1, wherein a casting to be sanded is supplied as a material into said drum body.