JPH09221753A - Eccentric weight type vibration-generation control method and eccentric weight type exciter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set force working so as to incline a center line to zero by installing and rotating a fixed eccentric weight and a movable eccentric weight to one shaft center line, controlling the rotational phase difference of the fixed eccentric weight and the movable eccentric weight and improving technique, by which exciting force is varied and adjusted. SOLUTION: A virtual plane s-s crossed at a right angle with a shaft X is assumed, and the center of gravity G of a fixed eccentric weight 16 and the center of gravity G' of a movable eccentric weight 17 are placed on the virtual plane s-s. Since the points of the application of force to an X-axis of centrifugal force working to the centers of gravity G, G' coincide, turning moment working so as to tilt the X-axis is not generated. Accordingly, the so-called 'miso' braying motion of the shaft is not generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for generating vibration and controlling the intensity of the vibration for civil engineering construction work such as pile driving, pile removing work and ground rolling work. The present invention relates to an eccentric weight type vibration exciter for carrying out the method.

[0002]

2. Description of the Related Art Vibrating devices (also called exciters) used in civil engineering construction work are roughly classified into an eccentric weight type and a piston type. Among the above, the eccentric weight type vibration generator generally has a structure in which a plurality of pairs of rotary shafts to which the eccentric weight is attached are arranged in parallel. According to such a configuration, the centrifugal vibrating force of the eccentric weight rotating in the opposite direction can be added in a desired direction and can be offset in an unnecessary direction. FIG. 3 is a schematic explanatory view of this type of rotary exciter, in which four rotary shafts 2 are provided with respect to the case 1.
A, 2B, 2C, 2D are arranged, and eccentric weights 3 are provided, respectively.
A, 3B, 3C, and 3D are attached, and gears 4A, 4B, 4C, and 4D are attached and meshed with each other to rotate synchronously.

[0003] When a pile driving operation is performed using the above-described exciter, prevention of vibration pollution and prevention of noise pollution are important issues. Next, technical problems relating to vibration pollution will be described with reference to FIGS. FIG. 4 is a schematic diagram for explaining vibration pollution in a pile driving operation. This figure shows a state in which the vibration device 6 is suspended by the crane boom 5, the upper end of the pile 7 is gripped by the chuck 6 a of the vibration device 6, and the pile 7 is vibrated and driven into the ground. Is drawn. Pile 7
When the pile driving work is started with the lower end of the pile touching the ground surface, if the vibration device 6 is fully operated from the beginning, the surface wave a generated on the ground surface at the pile driving point reaches the neighboring private house 8 with almost no attenuation. This causes vibration pollution problems. Here, if the vibrating force of the vibrating device 6 can be adjusted arbitrarily, the pile driving operation is started while giving a slight vibration in addition to the weight of the pile 7, and after driving several meters, the vibration may be gradually increased. . If the hypocenter position corresponding to the lower end of the pile 7 becomes deeper, the underground wave b is attenuated on the way to the private house 8, so that vibration pollution is slight.

FIG. 5 is a table showing changes in the vibration frequency at the time of starting operation and at the time of stopping the operation of the vibration device. The horizontal axis represents time. Start of operation time t _0, between time t ₁ to reach the rated operating state, frequency rises sharply as shown by arrow c. During the above frequency rise, the natural frequency of the ground n ₁ and the natural frequency of the crane boom n ₂ are passed. However, since the rotational speed increase period T ₁ at the start operation is generally short (e.g., about 3 seconds), the resonance problem when frequency of the vibration device matches the natural frequency, can be usually ignored it can. However, between the time t ₂ of stopping the energization of the motor of the vibrating device 6 (not shown) to the time t ₃ when the rotary shaft is stopped is gradually decelerated as indicated by the arrow d while continuing to rotate at a rotational axis of inertia .

Since the rotation speed reduction period T ₂ is a relatively long time (for example, about 50 seconds), the crane boom resonates and is damaged when passing through the natural frequency n ₂ of the crane boom on the way. There is a risk of suffering. Further, when passing through the natural frequency n ₁ of the ground, there is a possibility that vibration pollution may occur due to resonance of the ground. It stops the energization of the motor in said time t _2, the if it is possible to zero the vibratory force by changing the rotational phase of the eccentric weight of the vibrating device, issues resonance during shutdown operation of the vibration device Can be prevented.

Next, looking at the amount of energy supplied to the vibrating device, the vibrating device 6 from the time t ₀ to t ₁ described above.
If the speed is increased while the vibration is generated by the eccentric weight (not shown) of the vibration device while the rotation speed of the vibration device is increasing, a large-capacity motor or a large-capacity power supply facility is required to drive the vibration. . In this case, if the vibrating device starts the operation in a state where the vibrating force is reduced to zero by changing the rotation phase of the eccentric weight, if the vibrating force can be exerted after reaching the rated number of operations,
It is economical because the motor capacity and power supply capacity can be reduced.
This is because, after reaching the rated operation number, there is no need to store any more rotational energy in the rotating member, and the operation can be continued by replenishing energy sufficient to compensate for the attenuation of vibration.

[0007] In view of the above circumstances, an adjustment technique for increasing or decreasing the vibrating force of a vibrator has been developed and is known. Next, the principle of increasing and decreasing the vibrating force of the vibrator will be described. FIG. 6 is a schematic view for explaining the operation of the four-shaft, four-weight type exciter shown in FIG. 3 described above. FIG. 6A shows a case where the eccentric weight is lowered as in FIG. State,
(B) shows a state rotated by about 90 degrees, and (C) shows a state in which the weight is further rotated by about 90 degrees. In FIG. 6B, as compared with FIG. 6A, four eccentric weights 3
The positions of the centers of gravity of A to 3D are raised by the dimension h. For this reason, the case 1
Is depressed. Although the center of gravity of each of the four eccentric weights rises in this way, when observing the eccentric weights 3A and 3B in contrast and the eccentric weights 3C and 3D in comparison, Compared to the state, in the state of FIG. (B), the eccentric weights 3A and 3B are separated from each other by a distance L ₂
The distance between the eccentric weights 3C and 3D is close to each other, and the distance is L ₁
However, the total center of gravity position of the eccentric weights 3A and 3B does not move to the left and right, and is the same as the eccentric weight 3C.
The total center of gravity with D has not moved to the left or right. Therefore, no vibrating force is generated in the left-right direction. As described above, the oscillating device is configured to provide a plurality of eccentric weights and to take out the oscillating force in the vertical direction while canceling the oscillating force in the lateral direction, but as described above. Since the exciting force is controlled to be increased or decreased in order to prevent vibration pollution, it is possible to partially or completely cancel the upward and downward exciting forces of the pair of eccentric weights. FIG. 7 is a view for explaining a known technique of changing an exciting force by a combination of two eccentric weights, and (A) shows two eccentric weights exhibiting maximum exciting force. A schematic diagram showing a state, (B) a schematic diagram showing a state where the exciting force is medium, (C) a schematic diagram showing a state where the exciting force is slightly small, (D) a state where the exciting force is zero It is a schematic diagram showing. Of the two eccentric weights shown in FIG. 7, 9 is the rotary shaft 2
A fixed eccentric weight fixed to B ', 10 is a rotary shaft 2
It is a movable eccentric weight that can rotate relative to C '.
In the present invention, the fixed eccentric weight is an eccentric weight that is locked with respect to the rotation axis and is a member that rotates together with the rotation axis. . The relative position of the two eccentric weights 9 and 10 in FIG. 7A is the same as the eccentric weight 3 in FIG. 6A described above.
This is the same as the relative position of B and 3C. Therefore, in the state of FIG. 7A, the two eccentric weights 9 and 10 are connected to the gear 4
When the components B'and 4C 'are rotated in synchronization with each other, an exciting force is generated as described with reference to FIG. In the state of FIG. 7D, the center of gravity of each of the two eccentric weights 9 and 10 is always the reference line MM (vertical bisector of a line segment connecting the two rotating shafts 2B 'and 2C'). ), The vertical excitation force is zero. 7 (B) and 7 (C) are intermediate states of the above (A) and (D), respectively (A)
A vertical motive force smaller than that in the case of (D) and larger than that in the case of (D) is generated. And (B) figure is (C)
Since the state is closer to the state of (A) than the figure, when listed in descending order of vibration force, (A), (B), C), and (D) are obtained. In order to show the principle of the vibration force increasing / decreasing control in FIG. 7 described above, the two rotary shafts 2B ′ and 2C ′ are connected to the synchronous transmission gear 4.
Although it is drawn so as to rotate synchronously by B ', 4C', two eccentric weights may be arranged on one rotary shaft to simplify the structure. FIG. 8 is a schematic diagram of a mechanism in which a fixed eccentric weight is fixed to a common rotating shaft and the movable eccentric weight can adjust the relative rotation angle position with respect to the common rotating shaft. The fixed eccentric weight 9 is fixed to the rotating shaft 2 and rotates together. The movable eccentric weight 10 can be adjusted by changing the mounting angle position with respect to the rotary shaft 2 as indicated by arc arrows i-j, and can be maintained in the adjusted state. The state illustrated in FIG. 8 corresponds to the state illustrated in FIG. 7B described above, and the vibrating force is moderate. From this state, when the movable eccentric weight is rotated and fixed in the direction of arrow i, the state of FIG. 7D is approached and the vibrating force decreases. Further, when it is rotated in the direction of arrow j, as shown in FIG.
The vibration force increases as the state (A) approaches. The vibrating force is adjusted as described above. FIG. 9 shows a vibration generator in which a fixed eccentric weight and a movable eccentric weight are arranged on a common single shaft so that the vibration force can be adjusted to be increased or decreased as shown in FIG. 8 above. It is a perspective view which shows a prior art example. Two rotating shafts 2A, 2
B is arranged in the horizontal direction and is synchronously rotated in the opposite direction (clockwise and counterclockwise) by the drive pulley 11 and the synchronous rotation transmission gears 4A and 4B in order to cancel the horizontal exciting force. Is. The fixed eccentric weight 9A is fixed to the rotating shaft 2A. The movable eccentric weight 10A is rotatably supported on the rotary shaft 2A, and can adjust and fix the rotation with respect to the fixed eccentric weight 9A. That is, the movable eccentric weight 10A has a plurality of adjusting female screw holes 12 (only one is shown in the figure). When the set bolt 14 is screwed into the female screw hole 12 and tightened with the hexagon wrench 15 and detented with the knock pin 13, the angular position of the movable eccentric weight 10A is fixed. FIG. 10 is a view for explaining the relationship between the rotary shaft, the fixed eccentric weight, and the movable eccentric weight in the vibration oscillating machine equipped with the conventional adjustment mechanism shown in FIG. FIG. 3A is an external perspective view drawn by partially cutting, and FIG. 3B is a schematic view drawn as seen in a direction parallel to the rotation axis. 23a, 23b shown in FIG.
23c is a scale, and the unit is kg · cm. By aligning the scale and screwing the set bolt,
As shown in (B), the movable eccentric weight takes three angular positions and relatively rotates like 10a, 10b, and 10c to change the vibration force. The vibration generator according to the related art shown in FIGS. 7 to 10 can increase / decrease the vibration force as described above.

When an attempt is made to increase or decrease the exciting force in the conventional exciter described with reference to FIGS. 7 to 10, the operation will be easily understood from the structure shown in FIG. Stop, the knock pin 13 is pulled out, the set bolt 14 is pulled out, the movable eccentric weight 10 is manually turned to align the scales (reference numerals 23a to 23c in FIG. 10), and then the set bolt 14 is screwed again and tightened. The knock pin 13 must be used to stop the rotation. In the prior art, the above operations are required to adjust the increase and decrease of the vibrating force. As described above with reference to FIG. 4, since the vibrating device 6 is attached to the upper end of the pile 7, it is suspended and lowered by the crane boom 5, and then lifted by the crane boom 5 again to move the upper end of the pile 7. A lot of time and effort must be spent on the work. As shown in FIG. 7, which has been previously lifted as a principle diagram, a fixed eccentric weight 9 and a movable eccentric weight 1
It is conceivable that the structure in which 0 and 0 are attached to different rotating shafts is configured by actual members, and that the increase / decrease of the exciting force is adjusted while continuing the operation of the exciter.
Since the movable eccentric weight 10 must be rotated 180 degrees (relative to the fixed eccentric weight 9) between the state of (A) and the state of FIG. It has not been put to practical use because it has a poor responsiveness of operation and requires a large rotational torque for the rotational operation for adjustment.

In view of the above-mentioned circumstances, a vibration oscillating machine having a structure in which a movable eccentric weight and a fixed eccentric weight are arranged with respect to a common rotation center axis is applied. Good responsiveness of the vibrating force increase / decrease adjustment operation. To provide an eccentric weight oscillating force control method and an eccentric eccentric weight mechanism for oscillating, which requires a small drive torque for adjusting the increase / decrease of the oscillating force. Two eccentric weights are provided, and one of the two eccentric weights is attached by locking relative rotation with respect to the rotary shaft member to form a fixed eccentric weight. The other eccentric weight is attached to the fixed eccentric weight so that the other eccentric weight can rotate relative to the rotation center axis to form a movable eccentric weight, and the center of gravity of each of the two eccentric weights is The state of being symmetrically positioned with respect to the rotation center axis is called a reference state, and the movable eccentric weight is rotated relative to the fixed eccentric weight within a range of an acute angle θ from the reference state. , Adjust the magnitude of the vibration force of the vibration mechanism consisting of the two eccentric weights And, with respect to the movable eccentric weight fixed eccentric weight, it is effective to phase control so as not to rotate over a relatively acute angle theta. According to the above-mentioned technique, it is sufficient to relatively rotate the movable eccentric weight by an acute angle between the state where the excitation force is maximum and the state where the excitation force is zero. Moreover, within the range of the acute angle θ around the reference state, the driving torque required for adjusting and rotating the movable eccentric weight during operation is small, so that the adjusting operation can be performed while continuing the operation.

The above-mentioned technique relating to the increase / decrease adjustment of the exciting force is separately applied by the present applicant (Japanese Patent Application No. 7-159479).
No.) prior invention.

[0011]

According to the invention of the above-mentioned prior application, since the oscillating force of the eccentric weight type can be continuously increased / decreased, the oscillating force can be increased / decreased to prevent the vibration pollution. There are many places that contribute to mitigation, and moreover,
Since the two eccentric weights (the fixed eccentric weight and the movable eccentric weight) are supported by the common rotation center axis, the vibration oscillating machine as a whole can be made compact. However, in the invention of the above-mentioned prior application, attention is paid to the point that "the rotational phase of two eccentric weights attached to one shaft is adjusted to increase or decrease the excitation force,""Keeping the dynamic balance of the rotating member composed of the two eccentric weights" was not taken into consideration. To be precise, the invention according to the prior application did not lose the dynamic balance, but the embodiment according to the invention according to the earlier application maintained the dynamic balance. However, the invention was not conscious of achieving dynamic balance, and did not specify a configuration that is indispensable for achieving dynamic balance. The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technique for balancing the dynamics of a rotary system when the vibration force control technique according to the invention of the prior application is implemented. .

[0012]

The basic principle of the present invention created to achieve the above object will be briefly described with reference to FIG. 1B corresponding to the embodiment. The center of gravity G and the center of gravity G ′ of the fixed eccentric weight 16 and the movable eccentric weight 17 having an eccentric moment are positioned on a virtual plane s−s orthogonal to the X axis. The fixed eccentric weight 16 and the movable eccentric weight 17 rotate about the X axis and change the mutual phase difference, but the centers of gravity G and G'are always on the virtual plane s-s. . Therefore, when the centers of gravity G and G'rotate about the X axis, a centrifugal load is generated, but no force acting to incline the X axis is generated.

According to the structure of the invention of claim 1 created based on the principle described above, the center line of the rotating shaft is defined as the X axis, and two eccentric weights having the same eccentric moment with respect to the X axis are arranged. , The center of gravity of each of the above two eccentric weights,
It is characterized in that the two eccentric weights are rotated about the X axis while being positioned on the same plane perpendicular to the X axis and controlling the rotational phase difference between the two eccentric weights.
According to the invention of claim 1 described above, since the two eccentric weights having the same eccentric moment are rotated around the X axis and the rotational phase difference is controlled, the two eccentric weights are controlled. The total eccentric moment of changes with the phase difference. Therefore, the exciting force can be changed regardless of the change of the rotation speed, which is effective for reducing or preventing the vibration pollution. Moreover, since the center of gravity of each of the two eccentric weights rotates on the plane perpendicular to the center axis of rotation, no force for tilting the rotation axis in the X-axis direction is generated. The reason is that, assuming three orthogonal axes including the X axis, the Y axis and the Z axis are the virtual planes (planes orthogonal to the X axis).
When positioned above, the center of gravity G and the center of gravity G ′ of the two eccentric weights respectively rotate on the YZ plane, and the centrifugal force due to this rotation is the force within the YZ plane. For this reason, a centrifugal force is generated in the direction in which the rotation axis in the X-axis direction is translated, but the force in the direction in which the X-axis is rotated about the Z-axis or the X-axis is rotated about the Y-axis. The force to try does not occur. That is, a force that causes a so-called miso-grip motion is not generated on the rotation axis in the X-axis direction. Therefore, the supporting condition of the rotary shaft is improved and the bearing load is reduced,
Noise generation from bearings is reduced. In addition, the effects of reducing the heat generation of the bearing and extending the service life can be obtained.

In addition to the configuration of the invention of claim 1, the configuration of the invention of claim 2 limits the maximum angle at which the two eccentric weights can relatively rotate with respect to the X axis to about 60 degrees. It is characterized in that the phase difference between the two eccentric weights is changed within a range of about 30 degrees from the reference state, with a state in which both eccentric weights are symmetrically positioned with respect to the X axis as a reference state. According to the invention of claim 2 described above, the vibration force is minimized in the reference state, and the phase difference in the reference state is set to zero, and the phase difference between the two eccentric weights is changed within 30 degrees. Therefore, the operating torque required for the phase control is relatively small, and it is relatively easy to exert a desired vibration force. Here, there is a close correlation between the width of the range for changing the oscillating force of the eccentric weight type vibrator and the magnitude of the operating force required to change the oscillating force. If so, a large operation force is required. Therefore, by applying the invention of claim 2 and limiting the phase difference change within 30 degrees, it is possible to obtain an exciter force change range that is sufficient for practical use and that is sufficient for practical use. it can. In the invention of claim 2, since the control range of the phase difference is treated as an independent variable, the maximum value of the exciting force that can be generated is restricted as a dependent variable. However, even if the phase difference is fixed to a certain fixed value, the vibration force can be increased in direct proportion to the square of the rotation speed by increasing the rotation speed of the eccentric weight. The restriction on the maximum value of the excitation force due to the application of the invention of claim 2 does not become a drawback that reduces the practical value of the present invention.

In addition to the configuration of the invention of claim 2, the configuration of the invention of claim 3 makes the phase difference of the two eccentric weights closer to the standard state, and the total eccentric moment of the two eccentric weights. It is characterized in that the vibration acceleration generated when the amount is reduced is made almost gravitational acceleration or smaller than the gravitational acceleration. According to the third aspect of the invention described above, since the vicinity of the lower limit of the phase difference control range can be reduced, the phase difference control operation becomes correspondingly easier. By applying this technology, the lower limit of the range in which the magnitude of the excitatory force can be adjusted does not necessarily become "excitatory force zero", but even if the exciting force cannot be completely reduced to zero, vibration pollution cannot be prevented. There is no fear of impeding the reduction effect. The reason is as follows. That is, the gravitational acceleration (g = 980 cm / sec · sec) always acts downward on the civil engineering equipment (for example, steel sheet pile or steel pipe pile) that is the target member of the present invention. Therefore, when the vibration acceleration in the vertical direction is superimposed on this, if the value of the vibration acceleration does not exceed the gravitational acceleration, the above-mentioned equipment (object to which vibration is applied) does not generate vertical vibration. If this state is metaphorically described, the weight of the above-mentioned equipment (for example, a pile) changes without vertically vibrating. More specifically, the vibration value fluctuates between a value within twice the original weight and zero. Therefore, the self-weight subsidence force into the ground is almost doubled without propagating the vibration wave to the ground, so if the bearing capacity of the ground surface is not large, the penetration of the pile to a certain extent without vibration is pollution. You can do it if you can. Whether or not such effects can be exhibited is not always effective because it depends on the soil quality near the surface, but it is an exceptional special case that construction such as pile punching and rolling compaction is performed on hard ground. Since, in general, the soft ground is targeted for construction, there are many cases where the invention of claim 3 is a working condition in which the practical value can be exhibited. This technology can be widely applied not only to punching out piles, but also to compaction work such as rolling compaction.

According to a fourth aspect of the present invention, a tubular outer shaft having an eccentric weight different from the above is fitted to the inner shaft having the eccentric weight attached so as to be relatively rotatable. The eccentric moments of the two eccentric weights are equal to each other, and the center of gravity of each of the two eccentric weights is located on the same plane perpendicular to the inner axis and the outer axis. And According to the invention of claim 4 described above, the center line of the inner shaft and the center line of the outer shaft necessarily coincide with each other, and the two eccentric weights of the eccentric weight and the eccentric weight different from the eccentric weight. Are rotated about a common axis, the exciting force can be increased or decreased by adjusting the phase difference between the eccentric weights. In this case, since one of the eccentric weights is attached to the inner shaft, the tubular outer shaft to which the other eccentric weight is attached becomes structurally difficult to support in a cantilevered shape, and thus the inevitable The eccentric weights must be supported in a fixed shape (outer shaft), but most of the period (for example, 99% or more) in which both the eccentric weights rotate and generate vibrations is the same in both directions. In addition, the inner shaft and the tubular outer shaft rotate together because they can be rotated at the same number of rotations. The relative rotation between the inner shaft and the tubular outer shaft is only for a short time to control the phase difference, and in this case, the relative rotation speed between the inner shaft and the tubular outer shaft is extremely low (for example, vibration is generated). Therefore, it is structurally easy to support the centrifugal force on the tubular outer shaft via the inner shaft. Therefore, it is structurally easy to support the centrifugal force on the tubular outer shaft. In the case of carrying out the above, there is no possibility of technical difficulties in supporting centrifugal force due to rotation driving, transmitting operating force for phase control, and lubricating between the inner shaft and the outer shaft.

According to a fifth aspect of the present invention, the two gears to which the eccentric weights are fixed are rotatably supported by the same gear shaft, and fixed to each of the two gears. The eccentric moments of the two eccentric weights with respect to the gear shaft are equal to each other, and the rotation loci circles of the centers of gravity of the two eccentric weights are located on the same plane. . According to the invention of claim 5 described above, since each of the two eccentric weights is fixed to the gear, the two eccentric weights can be rotationally driven via the respective gears, It is also easy to control the phase difference between the two eccentric weights. The locus circles of the centers of gravity of these two eccentric weights are originally located on a plane perpendicular to the gear axis, but the rotation locus circles of the two eccentric weights are located on the same plane. This means that the rotation locus circles of these two centers of gravity coincide or are concentric circles. Therefore, the resultant force of the centrifugal forces generated by the two eccentric weights intersects the center line of the gear shaft and is perpendicular to the center line of the gear shaft. Therefore, the resultant force of the centrifugal force acts so as to move the gear shaft in parallel, and does not generate a rotational moment that tends to tilt the gear shaft. As a result, the load of the bearing that supports the gear shaft is relatively light, and the generation of noise is reduced.

The structure of the invention of claim 6 is the same as that of claims 4 and 5 above.
In addition to the configuration of the invention described above, two motors for individually rotating and driving each of the two eccentric weights are provided,
Further, it is characterized in that means for controlling the mutual rotational phase difference between the two motors is provided. According to the invention of claim 6 described above, the inner shaft and the tubular outer shaft of the invention of claim 4 or the two gears of the invention of claim 5 are individually driven to rotate by two motors. Therefore, it is possible to rotate the two eccentric weights in the same direction at the same rotation speed to generate an exciting force, and by controlling the rotation speeds of the two motors, Since the phase difference can be adjusted to increase or decrease the exciting force, it is effective for preventing or reducing vibration pollution. Since the eccentric weight can be rotationally driven and the phase can be controlled by operating the two motors as described above, the transmission mechanism between each of the two motors and the eccentric weight can be provided. A simple one is sufficient, and there is no need to install a clutch in the middle of the transmission system or to install another prime mover, and the operation is easy.

The structure of the invention of claim 7 is the same as in claims 4 and 5 above.
In addition to the configuration of the invention described above, one motor for rotationally driving the two eccentric weights is provided, and means for controlling a rotational phase difference between the two eccentric weights is provided. It is characterized by being According to the invention of claim 7 described above, since the two eccentric weights are driven to rotate by one motor, the two eccentric weights are stable unless trouble occurs in the middle of the transmission system. Then, they are rotated at the same rotation speed. Generally, the vibration exciter used in civil engineering construction works is basically operated in a steady state in which the maximum vibration force is generated, and since the work efficiency mainly depends on this steady operation state, the vibration in this steady state is generated. The practical value of stable machine performance is extremely high.
Further, according to the invention of claim 7, the rotation phase difference control means is provided in addition to the motor which is the driving force of the rotation drive, so that the phase difference between the two eccentric weights is controlled to increase or decrease the excitation force. The operation system for adjusting is simple. If the operation system is simple, the failure rate of the operation system is low, the operation reliability is high, the maintenance is easy, the service life of the operation system is long, and the phase difference control is easy and highly accurate. Can be done.

According to the structure of the invention of claim 8, in addition to the structure of the invention of claim 7, there is an even number of sets of fixed eccentric weights and movable eccentric weights having equal eccentric moments and sharing a rotating shaft. The fixed eccentric weights of each set are connected to each other so as to rotate synchronously via gears, and the movable eccentric weights of each set are also connected to each other synchronously rotate via gears. And a means for relatively rotating the fixed eccentric weight connected to each other and the movable eccentric weight connected to each other, and means for preventing the relative rotation. It is characterized by According to the invention of claim 8 described above, basically, as an effect inside the group of one fixed eccentric weight and one movable eccentric weight, By virtue of the action of the invention, the exciting force can be controlled to increase or decrease without the force of tilting the rotary shaft. Furthermore, since the above-mentioned groups are provided in even numbers, the vibrations in the desired direction can be generated between the groups. Can be added and strengthened, and the vibration in the unnecessary direction can be canceled out so that only the exciting force in the desired direction can be exerted. In this case, since the plurality of fixed eccentric weights and the plurality of movable eccentric weights are rotated synchronously via the respective gears,
The phase difference control of a plurality of sets of eccentric weights can be controlled and operated by a control system of one system, and there is no possibility that the rotational phase is deviated between the respective sets, and reliable control can be easily performed. it can.

According to a ninth aspect of the present invention, there are provided two eccentric weights having the same eccentric moment, and one eccentric weight having an eccentric moment equal to the sum of the eccentric moments of the two eccentric weights. A total of three eccentric weights are arranged with their central axes of rotation aligned, and the position of the total center of gravity of the two eccentric weights and the position of the center of gravity of the one eccentric weight are It is characterized by being located on the same plane perpendicular to the central axis. According to the invention of claim 9 described above, it is not necessary to position the center of gravity of each of the three eccentric weights in the same plane. Thereby, the structure for supporting each eccentric weight becomes mechanically very easy. That is, when the center of gravity of each of the two eccentric weights that are individually rotationally driven is to be positioned on the same plane perpendicular to the rotation axis, the location where the eccentric weight is attached to the rotation axis is the same as the above. It is impossible to place on a plane. On the other hand, when the invention of claim 9 is applied, for example, when one fixed eccentric weight and two movable eccentric weights are used, the centers of gravity of these three eccentric weights are on the same plane. The total center of gravity of the two movable eccentric weights and the center of gravity of the one fixed eccentric weight may be positioned on the same plane (perpendicular to the rotation axis) without needing to position them. Therefore, the position where each of these three total eccentric weights is attached to the rotary shaft can be set for each eccentric weight in the vicinity of a plane including the center of gravity and perpendicular to the axis. As a result, the mechanical condition of the structural portion for attaching each eccentric weight to the rotary shaft is easy, the degree of freedom in design is great, and the manufacturing cost is low.

According to a tenth aspect of the invention, in addition to the configuration of the ninth aspect of the invention, a total of three eccentric weights including the two eccentric weights and one eccentric weight are arranged in the same direction. A driving mechanism for rotating the two eccentric weights, and the two eccentric weights are driven in conjunction with each other so as to rotate while maintaining the same rotation phase, and the one eccentric weight and the two eccentric weights are also driven. Is provided with a control mechanism for adjusting the phase difference with the eccentric weight. According to the invention of claim 10 described above, a total of three eccentric weights, one eccentric weight and two eccentric weights, can be rotated together to generate an exciting force, Moreover, the rotational phase difference can be adjusted with the total center of gravity of the two eccentric weights kept on the same plane (perpendicular to the rotation center axis) with respect to the center of gravity of one eccentric weight, so that the rotation center axis can be adjusted. The vibrating force can be adjusted up or down without generating a force that tends to tilt, exhibiting a reliable vibrating function and a reliable vibrating force adjusting function, and the unique effect of the invention of claim 9 (eccentricity Vibration pollution can be effectively prevented or reduced without hindering the support of the weight.

The structure of the invention of claim 11 is the same as that of claim 10.
In addition to the structure of the invention of claim 1, it is provided with one inner shaft and two tubular outer shafts fitted to the inner shaft so as to be rotatable relative to the inner shaft. A weight is attached to the one inner shaft, and the two eccentric weights are respectively supported by the two tubular outer shafts. According to the eleventh aspect of the invention described above, when a total of three eccentric weights are formed by applying the invention of the ninth aspect, a drive for supporting and rotating each of the three eccentric weights. The difficulty of the mechanical conditions of the system can be eliminated,
In particular, the bending stress of the rotary shaft can be reduced. That is, when the center lines of the rotation shafts of the three eccentric weights are made to coincide with each other, and the three eccentric weights are rotationally driven while controlling the rotation phase, the centrifugal force received by the rotation shafts is It becomes a problem that it is difficult to withstand the bending deformation of the rotating shaft caused by the bending deformation. Therefore, according to the structure of claim 11, one eccentric weight is attached to one inner shaft to support / rotatably drive, and two outer shafts are fitted to the one inner shaft. When the eccentric weights are attached one by one and are supported and driven to rotate, the bending stress of the rotary shaft member that supports these three eccentric weights can be reduced, and each of the three eccentric weights can be reduced. It is possible to support individually and rotate them individually, and to easily and reliably control the rotational phase difference between one eccentric weight and two eccentric weights.

The structure of the invention of claim 12 is the same as that of claim 11.
In addition to the configuration of the invention, the rotational phase difference between the one eccentric weight and the two eccentric weights or the rotational phase difference between the inner shaft and the tubular outer shaft does not exceed 60 degrees. It is characterized in that it is mechanically constrained and the phase difference is controlled between 0 and 30 degrees. According to the twelfth aspect of the invention described above, the rotational phase difference between "one eccentric weight" and "two eccentric weights keeping the same rotational phase" is changed between 0 and 30 degrees. Therefore, it is possible to increase / decrease the exciting force with a relatively small operating force. Moreover,
Rotational phase difference should not exceed 60 degrees, ie ± 30
Since it is mechanically constrained so as not to exceed the degree, there is no possibility that the phase difference is erroneously controlled and the phase difference is made larger than 30 degrees. If the phase difference exceeds 30 degrees, the operating force required for the phase control will be remarkably large and the control may be lost. Therefore, it is guaranteed that the phase difference does not exceed 30 degrees. Is high, and there is no risk of accidentally causing vibration pollution.

According to a thirteenth aspect of the invention, a plurality of A-group eccentric weights are arranged with respect to a common rotation center line X, and a plurality of B-groups are arranged with respect to the rotation center line X. Of the plurality of eccentric weights of the group A and the total eccentric moment of the plurality of eccentric weights of the group B with respect to the X axis are equal to each other. , Or almost equal. According to the invention of claim 13 described above, the general eccentric moment of the plurality of eccentric weights of the A group and the total eccentric moment of the plurality of eccentric weights of the B group are equal or almost equal. Within the constraint, individual eccentric weights can be arbitrarily configured, so that the degree of freedom in design is large. Then, if the total eccentric moment of the A group and the total eccentric moment of the B group are configured to be equal to each other, by controlling the phase difference between the two groups, the exciting force is made equal to the rated value and zero. Although it can be changed between time, in actual work it is not often the case that the exciting force does not have to be completely zero (for example, it is sufficient if the vibration acceleration is equal to the gravitational acceleration). In such a case, by setting the total eccentric moments of both the A and B groups to be substantially equal, it is possible to construct a vibrating machine having practical value.

The structure of the invention of claim 14 is the same as that of claim 13.
In addition to the configuration of the invention described above, a plurality of eccentric weights of the A group are fixed to a rotary shaft and are rotationally driven by a drive means of the A system. The weight is rotatably supported relative to the rotary shaft and is rotationally driven by the drive means of the B system, and the rotational phase difference between the drive means of the A system and the drive means of the B system. It is characterized by being able to control. According to the fourteenth aspect of the invention described above, the rotational drive and the phase control of the plurality of eccentric weights can be easily performed by a simple mechanism. That is, when the invention of claim 13 is applied to configure two groups A and B each including a plurality of eccentric weights, the degree of freedom in designing the eccentric weights in each group increases. As described above, since the number of eccentric weights is large (at least four), the drive mechanism and the phase difference control mechanism for these many eccentric weights tend to be complicated.
Therefore, in addition to the configuration of the invention of claim 13, claim 14
When the eccentric weight is rotationally driven for each group and the phase is controlled for each group by applying the invention described in (1), a simple mechanism conforming to the rotational drive / phase control mechanism of the exciter consisting of two eccentric weights is used. It becomes possible to drive and control.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a main part of an eccentric weight type vibration oscillating device according to the present invention. FIG. 1A shows the center line X--X of an eccentric weight gear in one embodiment about the Z axis. FIG. 6 is an exploded perspective view schematically drawn by bending by an angle φ, and FIG. 6B is a partial cross-sectional view illustrating an eccentric weight and its supporting / transmission member in an embodiment different from the above. (See FIG. 1A) The eccentric weight gear shaft 21 is drawn in a shape bent at a right angle, but the substance is straight and is arranged along the XX axis. A fixed eccentric weight gear 20 and a movable eccentric weight gear 22 are supported by the shaft 21. One of the two eccentric weight gears 20 and 22 may be fixed to the gear shaft 21, but both gears (20, 22) are rotatably supported. A gear boss 26 is integrally connected to each of the eccentric weight gears 20 and 22,
These gear bosses 26 are fitted onto the eccentric weight gear shaft 21. The fixed eccentric weight 9 and the movable eccentric weight 10 have the same shape and the same size, and are integrally connected to the fixed eccentric weight gear 20 and the movable eccentric weight gear 22, respectively. 1 above
The pair of eccentric weights 9 and 10 has a cross-sectional shape of a plane perpendicular to the X axis similar to a fan shape, and the angle Ψ formed by the two surfaces corresponding to the two radial sides of the fan shape is basically Ψ = 180 ° −α, and in the present embodiment, the angle α is 30 °. When practicing the present invention, the angle α is not necessarily 30.
However, it is preferably about 30 degrees or less as described later with reference to FIG. This is because the rotational torque (operating force) required for the operation for controlling the phase difference of the eccentric weight significantly increases when the angle α exceeds 30 degrees. The fixed eccentric weight 9 and the movable eccentric weight 10 are formed with a center hole (concave cylindrical surface) having a radius dimension r along the X-axis which is the center line, and with respect to the gear boss 26 having the radius dimension r. Are fitted so that they can rotate relative to each other. Further, the length dimension of the gear boss 26 in the X-axis direction is L while the length dimension of the eccentric weights 9 and 10 in the X-axis direction is L.
The center hole (concave cylindrical surface) of the fixed eccentric weight 9 is fitted to the counterpart gear boss 26, and the center hole of the movable eccentric weight 10 is also fitted to the counterpart gear boss 26. It is like this. As a result, in the assembled state, the fixed eccentric weight 9 and the movable eccentric weight 10 are symmetrical with respect to the X axis, and the X coordinate values of the center of gravity of the respective eccentric weights are equal. That is, both center of gravity are located on the same plane perpendicular to the X-axis, and loci circles of both centers of gravity coincide or become concentric circles. Therefore, even if a centrifugal force acts on each of the center of gravity of both, there is no possibility that the centrifugal forces of both intersect at the same point on the X-axis and the eccentric weight gear shaft 21 is tilted to cause a miso-grip motion. As a result, the load condition of the bearing that supports the eccentric weight gear shaft 21 is good, and noise generation is reduced.

FIG. 11 is a cross-sectional view showing the entire rotating system including the drive system of the eccentric weight type vibrator shown in FIG. 1 (B), and the components of the phase difference control mechanism are indicated by chain lines. FIG. 7 is a configuration / operation explanatory view additionally shown. FIG. 1B shows one fixed eccentric weight 9, one movable eccentric weight 10, one fixed eccentric weight gear 20, and one movable eccentric weight gear 22. Although one set of vibration generating units attached to the eccentric weight gear wheel shaft 21 is illustrated, two sets of the above vibration generating units are shown in FIG. 11. That is, two fixed eccentric weights 9A and 9B and two movable eccentric weights 10A and 10B.
And the two fixed eccentric weight gears 20A and 20B and the two movable eccentric weight gears 22A and 22B, respectively, are assembled to the two eccentric weight gear shafts 21A and 21B to form two sets. The vibrating units [A] and [B] are formed. FIG.
Although the gear boss 26 shown in (B) is also provided in FIG. 11, the reference numeral “2” is provided to facilitate the reading.
Only "6" is entered, and the entry of member names is omitted.

In the embodiment shown in FIG. 11, the seven gears shown in the drawing have the same number of teeth, the same module and the same diameter. The drive gear 51 rotated by one drive motor 52 is meshed with the fixed eccentric weight gear 20A, and the fixed eccentric weight gear 20A is meshed with the same 20B.
As a result, the fixed eccentric weight 9A and the fixed eccentric weight 9B of each of the two sets of vibration generating units are always rotated at the same rotational speed in opposite directions. The fixed eccentric weight gear 20B
Is meshed with the phase control gear / instep 24A. The phase control gear / instep 24A and the phase control gear / Otsu 24B are X
A phase control gear shaft 25 installed parallel to the shaft is rotatably supported so that the phase control gear / B 24B sequentially moves the movable eccentric weight 10B and the movable eccentric weight 1
It is meshed with 0A. The two eccentric weight gear shafts 21
Fixed eccentric weight gear 20 for each of A and 21B
Each of A and 20B is linked by a key k. The movable eccentric weight gears 22A and 22B are fitted to the two eccentric weight gear shafts 21A and 21B, respectively, so as to be rotatable relative to each other. As a result, the movable eccentric weight 10A of each of the two sets of vibration generating units is
The same 10B and the phase control gear / Otsu 24B are always rotated at the same rotation speed.

The phase control gear / instep 24A and the phase control gear shaft 25 are connected by a key k. The phase control gear / Otsu 24B is rotatably fitted relative to the phase control gear shaft 25, and between the two,
"Clutch means 53 capable of braking and releasing relative rotation of both" and "fluidic reversible rotation mechanism (for example, vane motor) 5 for relatively rotating both.
4 ”is installed. When the drive motor 52 is rotating, the phase control gear / instep 24A is always rotated in the opposite direction to the drive motor 52 at the same rotation speed as the drive motor 52. When the clutch means 53 is in the "contact" state, the Otsu 24B is caused to rotate in the same direction as the phase control gear / instep 24A and at the same rotational speed. Further, when the clutch means 53 is “disengaged”, the fluid type reversible operation mechanism 54 can be operated to advance or retard the rotational phase with respect to the phase control gear / instep 24A. When the rotation phase of the phase control gear B 24B is advanced or delayed as described above, the fixed eccentric weights 9A, 9
The phase difference between the movable eccentric weights 10A and 10B with respect to B is changed.

The phase difference between the movable eccentric weight and the fixed eccentric weight is limited by the rotation stroke angle of the fluid type reversible rotation mechanism 54. Further, the angle θ shown in FIG.
Is also constrained by. This restriction has not only the negative meaning of narrowing the change range of the excitation force, but also the positive meaning of not increasing the operation required force (rotational moment) of the phase control. FIG. 2 is shown for explaining the phase control of the eccentric weight in one embodiment of the present invention. (A) shows the fixed eccentric weight and the movable eccentric weight in symmetrical positions with respect to the rotation axis. It is a schematic diagram which drew the reference state in which an exciting force becomes zero, and (B) is a schematic diagram which drew the movable eccentric weight from the reference state by an acute angle θ to maximize the exciting force. Yes, (C) is a schematic diagram depicting a state in which the excitation force is moderately adjusted. The fixed eccentric weight 16 and the movable eccentric weight 17 have a fan shape having substantially the same shape and size when viewed in a direction parallel to the rotating shaft 2, and have a thickness in the depth direction of the paper surface. It has a flat plate shape. However, since it has a thickness dimension larger than the fan-shaped radius dimension, the appearance impression is columnar rather than plate-like.

In the state of FIG. 3A in which both eccentric weights 16 and 17 are symmetrical with respect to the rotation shaft 2, the total center of gravity of the eccentric gravity centers G and G'is located on the center line of the rotation shaft 2. doing. Therefore, even if the two eccentric weights 16 and 17 rotate around the rotation axis 2 while maintaining the relative positional relationship, no centrifugal force acts and the vibrating force is zero. This state is the reference state described above.

Fixed eccentric weight 16 and movable eccentric weight 17
The apex angle ψ of the fan-shaped end face is set to Ψ = 180 degrees −θ. The above-mentioned angle θ needs to be an acute angle, but is preferably 30 degrees as shown in the figure. However, in addition to the actual manufacturing error,
I also want the degree of freedom in design, so it is practical to set it to 30 degrees ± 10 degrees.

The fan-shaped surface of the fixed eccentric weight 16 on the front side of the paper surface of the fixed eccentric weight 16 and the fan-shaped surface of the movable eccentric weight 17 on the front side of the paper surface are substantially flush with each other (parallel to the paper surface). )
Are aligned. Similarly, the fan-shaped surface on the depth side of the paper is also aligned on the same surface. Thereby, the fixed eccentric weight 16
And the center of gravity G ′ of the movable eccentric weight 17 are
Are aligned on the same plane perpendicular to (parallel to the paper surface).

When the movable eccentric weight 17 rotates with respect to the fixed eccentric weight 16 by the angle θ from the reference state as shown in FIG. 2B, the planes corresponding to the fan-shaped sides come into contact and rotate. Is locked so that it cannot rotate beyond the angle θ. In the state of FIG. 2 (B), the centers of gravity G and G ′ of both eccentric weights are
Since the total center of gravity is eccentric with respect to the center line of the rotating shaft 2, when rotating in the state of this figure (B), a centrifugal force acts and an exciting force is generated. Since the movable eccentric weight 17 cannot rotate any more (greater than the angle θ) with respect to the fixed eccentric weight 16, the state shown in FIG. It is.

The reason why the movable eccentric weight is not rotated beyond the acute angle θ is as follows. Assuming that the rotation speed of the rotary shaft 2 is constant, the rotational energy is small in the state of FIG. (A) and large in the state of (B). Therefore, the movable eccentric weight 1 with respect to the fixed eccentric weight 16
Regarding the holding of the position of 7, the state of FIG. 7A is unstable, and the state of FIG. 7B is stable. For this reason, the operation for changing the reference state of FIG. 7A to the state of the maximum vibrating force of FIG. 7B requires only a small required torque (sufficient to overcome the frictional force), but the operation of FIG. The operation of changing from the state of maximum vibration to the reference state shown in FIG. 3A requires a corresponding drive torque. However, since the deviation angle from the reference state is limited to within the acute angle θ, the required torque for setting the reference state is significantly smaller than that in the conventional technique rotated 180 degrees. If θ ≒ 30 degrees, the required torque is even smaller. As shown in FIG. 2C, when the movable eccentric weight 17 is rotated from the reference state by an angle φ satisfying φ <θ, a vibration force smaller than that in the state of FIG.

Since the angle φ can be changed steplessly within the range of 0 <φ <θ, the exciting force can be arbitrarily adjusted steplessly from zero to the maximum. it can.

In carrying out the present invention, the minimum value of the increase / decrease adjustment of the excitation force does not necessarily have to be zero. The reason is that even if the vibration force is not completely zero, if the vertical vibration acceleration is smaller than the gravitational acceleration (980 cm / sec · sec), the equipment for civil engineering construction (eg, piles) that has been vibrated is used. Does not vibrate in appearance, so there is no risk of causing vibration pollution. A concrete means for completely eliminating the vibration force will be described with reference to FIG. 2. One of them is to provide a difference between the eccentric moment of the fixed eccentric weight 16 and the eccentric moment of the movable eccentric weight 17. It is to keep. With this configuration, the position of the total center of gravity of both eccentric weights 16 and 17 does not come to the center line of the rotating shaft 2 even if both eccentric weights are set to the standard state. Another means is that the eccentric moment of the movable eccentric weight 17 and the eccentric moment of the fixed eccentric weight 16 are made equal, and when the phase difference control is brought close to the reference state, the reference state is completely reached. The thing is not to do. Which of the above two means is selected is arbitrary.

A concrete supporting / driving mechanism for rotationally driving and phase controlling the eccentric weight as shown in FIG. 2 is shown in FIG.
It can also be configured as in (B). This Figure 1 (B)
2A corresponds to a plan view drawn by cutting a part of the mechanism drawn as a schematic side view in FIG.

One inner shaft 30 is arranged along the X axis,
Two tubular outer shafts 18, 18 ′ are fitted onto the inner shaft 30 so as to be relatively rotatable. The fixed eccentric weight 16 is connected to the inner shaft 30 via a key 34, and the movable eccentric weight 17 is fixed to the tubular outer shafts 18 and 18 '. The tubular outer shafts 18, 18 'are supported by bearing brackets 28 via bearings 29. The center of gravity G ′ of the movable eccentric weight 17 and the center of gravity G of the fixed eccentric weight 16 are located on an imaginary plane ss perpendicular to the X axis. Therefore, even if a centrifugal force acts on the center of gravity G, G ′, the lines of action of these centrifugal forces intersect at a point O on the X axis, and the inner shaft 30 arranged along the X axis. Also, there is no effect of inclining the tubular outer shafts 18 and 18 'to cause the miso movement.

The eccentric weight of the embodiment shown in FIG. 1A has a structure in which it is directly driven to rotate by a gear.
The eccentric weight of the embodiment shown in (B) has a structure in which the eccentric weight is rotationally driven by a rotating shaft (inner shaft and tubular outer shaft). These transmission systems can be combined, and FIG. 12 shows an oscillating unit including a fixed eccentric weight fixed to a rotary shaft and a movable eccentric weight rotatably attached to the rotary shaft. It is a horizontal sectional view of the exciter which is equipped. This embodiment has an A system drive motor Ma and its transmission system, and also has a B system drive motor Mb and its transmission system. The A system drive motor Ma rotationally drives the A system fixed eccentric weight 26 through the A system transmission pulley 48, the winding transmission means (belt) 47, the A system driven pulley 45, and the A system rotary shaft 31, and further The A system movable eccentric weight 39 is rotationally driven through the A system drive gear 33 and the A system driven gear 35. The drive motor Mb of the B system is the above A
Similarly to the system, the B system fixed eccentric weight 38 and the B system movable eccentric weight 37 are rotationally driven. When the drive motor Ma of the A system and the drive motor Mb of the B system are rotated at the same rotational speed, the eccentric weight of the A system and the eccentric weight of the B system rotate with a constant phase difference, and the A system Drive motor Ma
When the rotation speed is rotated at a higher speed than the drive motor Mb of the B system, the rotation phase of the eccentric weight of the A system leads the rotation phase of the eccentric weight of the B system, and is delayed when the rotation speed is low.
In this way, the excitation force can be generated and the increase / decrease of the excitation force can be adjusted.

As described above with reference to the embodiments, the center of gravity G of the fixed eccentric weight and the center of gravity G'of the movable eccentric weight are aligned on the surface s perpendicular to the rotation axis center line X. Then, there is an effect that the force in the direction of tilting the rotary shaft does not work, but the mechanical condition of the structure for attaching and supporting the eccentric weight to the rotary shaft is not always easy. FIG. 13 is an explanatory view schematically showing the position of the center of gravity of the eccentric weight with respect to the rotating shaft and the mounting structure. FIG. 13 (A) schematically shows the embodiment shown in FIG. 1 (A), and is movable with the center of gravity G of the fixed eccentric weight on a virtual plane s-s perpendicular to the rotation axis XX. The center of gravity G'of the eccentric weight is arranged. When such a configuration is adopted, the point T at which the fixed eccentric weight is attached to the rotation axis X
And the point T'where the movable eccentric weight is attached to the rotation axis X,
It cannot be placed on said surface s-s. Therefore, the line connecting the center of gravity G and the attachment point T is not perpendicular to the rotation axis X. Therefore, the structure connecting the center of gravity G and the attachment point T not only receives a simple tension (centrifugal force) but also receives a rotational moment in the plane of the drawing to generate a bending stress.
A similar problem exists in the relationship between the center of gravity G'of the movable eccentric weight and the mounting point T '.

As shown in FIG. 13 (B), the fixed eccentric weight is set to 2
Divided and if so, "the center of gravity G ₁ of the first fixed eccentric weight, total center of gravity G ₃ between the center of gravity G ₂ of the second fixed eccentric weight" is balanced with the center of gravity G 'of the movable eccentric weight The eccentric moment of one movable eccentric weight and the total eccentric moment of two fixed eccentric weights can be adjusted (or almost equal) to increase or decrease the exciting force, and The line connecting the centers of gravity G ′, G ₁ and G ₂ of the eccentric weights and the attachment points T ′, T ₁ and T _{2 of} the respective eccentric weights can be made orthogonal to the rotation axis X. If these lines are made orthogonal to each other, when each eccentric weight receives a centrifugal force, it mainly receives only a simple tensile force, and the mechanical condition of the supporting structure is significantly facilitated. In this case, the rotation drive / phase control mechanism mechanically constrains the two divided eccentric weights so that the two eccentric weights always maintain the same rotational phase, or the two divided eccentric weights always keep the same rotational phase. It suffices if they are rotationally driven so as to maintain the same rotational phase. In addition, the structure of the rotary shaft that supports one eccentric weight and the two divided eccentric weights in this way is, for example, one inner shaft 30 according to the embodiment of FIG. And two tubular outer shafts 18, 18 'may be used,
The support structure is not limited to this. Again, 1
In order to reduce the operating force, it is necessary to mechanically constrain the phase difference between each eccentric weight and the two divided eccentric weights to within 60 degrees and control operation between 0 and 30 degrees. desirable.

If the technical idea of dividing the eccentric weight shown in FIG. 13B is applied, the fixed eccentric weight is divided and the movable eccentric weight is also divided, if necessary. The eccentric weights have the same center of gravity s-
It is also possible to balance on s. FIG. 13 (C)
Represents the case where the fixed eccentric weight is divided into two and the movable eccentric weight is divided into three, and G ₄ and G ₅ are the respective centers of gravity of the two divided fixed eccentric weights, G ₆ is the total center of gravity. G ₁ ′, G ₂ ′ and G ₃ ′ are the center of gravity of each of the three divided movable eccentric weights, and G ₄ ′ is the total center of gravity thereof. Also in this example, the total center of gravity G of each
₆ and G ₄ ′ are positioned on the same plane s−s and balanced, and the degree of freedom in designing the individual eccentric weights is great. As a supporting structure for supporting and rotating each of a total of five eccentric weights divided as in the example of FIG. 13C, a structure as shown in FIG.
A heavy pipe structure may be applied, and a triple pipe structure may be used as necessary. Further, the eccentric weight is rotatably fitted to the support shaft (for example, like the support structure of the B system movable eccentric weight 37 by the A system rotary shaft 31 in the embodiment of FIG. 12), Can be rotationally driven via a gear (for example, the B system driven gear 41 in FIG. 12) that is integrally connected.

[0045]

According to the invention of claim 1, the two eccentric weights having the same eccentric moment have the X-axis of the X-axis. Since it is rotated around and the rotational phase difference is controlled, the total eccentric moment of the two eccentric weights changes with a change in the phase difference. Therefore, the exciting force can be changed regardless of the change of the rotation speed, which is effective for reducing or preventing the vibration pollution. Moreover,
Since the center of gravity of each of the two eccentric weights rotates on a plane perpendicular to the rotation center axis, a force that tilts the rotation axis in the X-axis direction does not occur. The reason is that, assuming three orthogonal axes including the X axis, the Y axis and the Z axis are set to the virtual plane (X
(The plane orthogonal to the axis), the center of gravity G and the center of gravity G ′ of the two eccentric weights rotate on the YZ plane,
The centrifugal force due to this rotation is a force in the YZ plane. For this reason, a centrifugal force is generated in the direction in which the rotation axis in the X-axis direction is translated, but the force in the direction in which the X-axis is rotated about the Z-axis or the X-axis is rotated about the Y-axis. The force to try does not occur. That is, a force that causes a so-called miso-grip motion is not generated on the rotation axis in the X-axis direction. Therefore, the supporting condition of the rotary shaft is improved, the bearing load is lightened, and the noise generation from the bearing is reduced.
In addition, the bearing heat generation can be reduced and the service life can be increased.

According to the second aspect of the invention, the vibration force is minimized in the reference state, and the phase difference in the reference state is set to zero, and the phase difference between the two eccentric weights is changed within 30 degrees. Therefore, the operating torque required for the phase control is relatively small, and it is relatively easy to generate a desired exciting force. Here, there is a close correlation between the width of the range for changing the oscillating force of the eccentric weight type vibration oscillating machine and the magnitude of the operating force required to change the oscillating force, so try to increase the range of change. If so, a large operation force is required. Therefore, by applying the invention of claim 2 and limiting the phase difference change within 30 degrees, it is possible to obtain an exciter force change range that is sufficient for practical use and that is sufficient for practical use. it can. In the invention of claim 2, since the control range of the phase difference is treated as an independent variable, the maximum value of the exciting force that can be generated is restricted as a dependent variable. However, even when the phase difference is fixed to a certain degree, by increasing the rotation speed of the eccentric weight, the exciting force can be increased in direct proportion to the square of the rotation speed. The restriction on the maximum value of the excitation force due to the application of the invention of claim 2 does not become a drawback that reduces the practical value of the present invention.

According to the third aspect of the present invention, since the vicinity of the lower limit of the phase control range can be reduced, the phase difference control operation becomes correspondingly easier. By applying this technology, the lower limit of the range in which the magnitude of the excitatory force can be adjusted does not necessarily become "excitatory force zero", but even if the exciting force cannot be completely reduced to zero, vibration pollution cannot be prevented. There is no fear of impeding the reduction effect. The reason is as follows. That is, the gravitational acceleration (g = 980 cm / sec · sec) always acts downward on the civil engineering equipment (for example, steel sheet pile or steel pipe pile) that is the target member of the present invention.
Therefore, when a vertical vibration acceleration is superimposed on this, the above-mentioned equipment (object to be vibrated) does not generate vertical vibration unless the value of the vibration acceleration exceeds the heavy acceleration. If this state is metaphorically described, the weight of the above-mentioned equipment (for example, a pile) changes without vertically vibrating. More specifically, the vibration value fluctuates between a value within twice the original weight and zero. Therefore, the self-weight subsidence force into the ground is almost 2 without propagating the vibration wave to the ground.
Therefore, if the bearing capacity of the ground surface is not large, it is possible to penetrate the pile to some extent without vibration-free pollution. Whether or not such effects can be exhibited is not always effective because it depends on the soil quality near the surface, but it is an exceptional special case that construction such as pile punching and rolling compaction is performed on hard ground. Since it is intended for soft ground in general, the invention of claim 3 is not a few cases where the working conditions are such that practical value can be exerted. This technology can be widely applied not only to punching out piles, but also to compaction work such as rolling compaction.

According to the invention of claim 4, the center line of the inner shaft and the center line of the outer shaft necessarily coincide with each other, and the eccentric weight and the two eccentric weights different from the eccentric weight are different from each other. Since the eccentric weights are rotated about a common axis, the vibration force can be increased or decreased by adjusting the phase difference between the eccentric weights. In this case, since one of the eccentric weights is attached to the inner shaft, the tubular outer shaft to which the other eccentric weight is attached is structurally difficult to support in a double-sided shape,
Inevitably, it must be supported in a cantilever manner (outer shaft), but most of the period (for example, 99% or more) in which both of the eccentric weights rotate and generate vibrations is the eccentric weight of both. Since the weight is rotated in the same direction at the same number of rotations, the inner shaft and the tubular outer shaft rotate together. Relative rotation between the inner shaft and the tubular outer shaft is only for a short time to control the phase difference,
Moreover, in this case, the relative rotation speed between the inner shaft and the tubular outer shaft is extremely low (for example, 1/10 of the rotation speed for vibrating).
Since it is less than 0), it is structurally easy to support the centrifugal force on the tubular outer shaft via the inner shaft, and when the invention of claim 4 is carried out, rotational driving is performed. There is no risk of technical difficulties in supporting the centrifugal force, transmitting the operating force for phase control, and lubricating the inner and outer shafts.

According to the fifth aspect of the invention, since each of the two eccentric weights is fixed to the gear, the two eccentric weights can be rotationally driven via the respective gears. It is also easy to control the phase difference between the individual eccentric weights. The locus circles of the centers of gravity of these two eccentric weights are originally located on a plane perpendicular to the gear axis, but the rotation locus circles of the two eccentric weights are located on the same plane. This means that these two gravity center rotation loci circles are coincident with each other or are concentric circles. Therefore, the resultant force of the centrifugal forces generated by the two eccentric weights intersects the center line of the gear shaft and is perpendicular to the center line of the gear shaft.
Therefore, the resultant force of the centrifugal force acts so as to move the gear shaft in parallel, and does not generate a rotational moment that tends to tilt the gear shaft. As a result, the load of the bearing that supports the gear shaft is relatively light, and the generation of noise is reduced.

According to the invention of claim 6, the inner shaft and the tubular outer shaft of the invention of claim 4 or the two gears of the invention of claim 5 are individually driven to rotate by two motors. Therefore, it is possible to rotate two eccentric weights in the same direction at the same rotational speed to generate an exciting force, and by controlling the rotational speed of the two motors, the phase difference Can be adjusted to increase or decrease the vibrating force, which is effective in preventing or reducing vibration pollution. Since the eccentric weight can be rotationally driven and the phase can be controlled by operating the two motors as described above, the transmission mechanism between each of the two motors and the eccentric weight can be provided. A simple one is sufficient, and there is no need to install a clutch in the middle of the transmission system or to install another prime mover, and the operation is easy.

According to the structure of claim 7, since the two eccentric weights are rotationally driven by one motor, the two eccentric weights are stable unless trouble occurs in the middle of the transmission system. Are rotated at the same rotation speed. Generally, a vibrator used in civil engineering construction work is basically operated in a steady state in which a maximum vibration force is generated, and the work capacity is mainly influenced by the steady operation state.
Practical value of stable excitation performance in this steady state is very high. Further, according to the invention of claim 7, the rotation phase difference control means is provided in addition to the motor which is the driving force of the rotation drive, so that the phase difference between the two eccentric weights is controlled to increase or decrease the excitation force. The operation system for adjusting is simple. If the operation system is simple, the failure rate of the operation system is low, the operation reliability is high, the maintenance is easy, the service life of the operation system is long, and the phase difference control is easy and highly accurate. Can be done.

According to the eighth aspect of the present invention, basically, as an effect inside the set of one fixed eccentric weight and one movable eccentric weight, the fourth or fifth aspect is provided.
By the action of the invention described above, the exciting force can be controlled to increase or decrease without the force of tilting the rotating shaft. Furthermore, since a plurality of the above groups are provided, a desired direction between the groups can be achieved. It is possible to add and intensify the vibrations and cancel out vibrations in unnecessary directions so that only the exciting force in the desired direction can be exerted. In this case, the plurality of fixed eccentric weights and the plurality of movable eccentric weights are rotated in synchronization with each other via gears, so that the phase difference control of the plurality of sets of eccentric weights is controlled by the control means of one system. It is possible to operate, and there is no possibility that the rotational phase will be misaligned between each pair, and reliable control can be easily performed.

According to the ninth aspect of the invention, it is not necessary to position the center of gravity of each of the three eccentric weights in the same plane. Thereby, the structure for supporting each eccentric weight becomes mechanically very easy. That is, when the center of gravity of each of the two eccentric weights that are individually rotationally driven is to be positioned on the same plane perpendicular to the rotation axis, the location where the eccentric weight is attached to the rotation axis is the same as the above. It is impossible to place on a plane. On the other hand, when the invention of claim 9 is applied, for example, when one fixed eccentric weight and two movable eccentric weights are used, the centers of gravity of these three eccentric weights are on the same plane. Without having to position
The total center of gravity of the two movable eccentric weights and the center of gravity of the one fixed eccentric weight may be positioned on the same plane (perpendicular to the rotation axis). Therefore, the position where each of these three total eccentric weights is attached to the rotary shaft is as follows:
It can be set near the plane including the center of gravity and perpendicular to the axis. As a result, the mechanical condition of the structural portion for attaching each eccentric weight to the rotary shaft is easy, the degree of freedom in design is great, and the manufacturing cost is low.

According to the invention of claim 10, a total of three eccentric weights, one eccentric weight and two eccentric weights, can be rotated together to generate an exciting force, and Since the total center of gravity of the two eccentric weights is kept on the same plane (perpendicular to the rotation center axis) with respect to the center of gravity of one eccentric weight, the rotation phase difference can be adjusted, so the rotation center axis can be tilted. The vibrating force can be increased / decreased and adjusted without generating the force to be exerted, and a reliable exciter function and a reliable vibrating force adjusting function are exhibited. Vibration pollution can be effectively prevented or reduced without hindering the support of the weight.

According to the invention of claim 11, said claim 9
When a total of three eccentric weights are configured by applying the invention of (3), it is possible to eliminate the difficulty of the mechanical condition of the drive system that supports and rotates each of the three eccentric weights. The bending stress of the rotating shaft can be reduced. That is,
Align the center lines of the rotation axes of the three eccentric weights with each other,
Moreover, if the three eccentric weights are rotationally driven while controlling the rotational phases, it becomes difficult to endure the bending deformation of the rotary shaft due to the centrifugal force applied to the rotary shaft. Therefore, according to the structure of claim 11, one eccentric weight is attached to one inner shaft to support / rotatably drive, and two outer shafts are fitted to the one inner shaft. When the eccentric weights are attached one by one and are supported and driven to rotate, the bending stress of the rotary shaft member that supports these three eccentric weights can be reduced, and each of the three eccentric weights can be reduced. It is possible to support individually and rotate them individually, and to easily and reliably control the rotational phase difference between one eccentric weight and two eccentric weights.

According to the twelfth aspect of the invention, the rotational phase difference between the "one eccentric weight" and the "two eccentric weights keeping the same rotational phase" can be changed between 0 and 30 degrees. So
It is possible to increase or decrease the excitation force with a relatively small operating force.
Moreover, since the rotational phase difference is mechanically restricted so that it does not exceed 60 degrees, that is, it does not exceed ± 30 degrees, the phase difference control operation is erroneously made larger than 30 degrees. There is no danger of it getting lost. If the phase difference exceeds 30 degrees, the operating force required for the phase control will be remarkably large and the control may be lost. Therefore, it is guaranteed that the phase difference does not exceed 30 degrees. Is high, and there is no risk of accidentally causing vibration pollution.

According to the thirteenth aspect of the present invention, the total eccentric moment of the plurality of eccentric weights of the group A and the total eccentric moment of the plurality of eccentric weights of the group B are equal,
Alternatively, the individual eccentric weights can be arbitrarily configured within the range of the general constraint that they are substantially equal, so that the degree of freedom in design is large. Then, if the total eccentric moment of the A group and the total eccentric moment of the B group are configured to be equal to each other, by controlling the phase difference between the two groups, the exciting force is made equal to the rated value and zero. Although it can be changed between time, in actual work it is not often the case that the exciting force does not have to be completely zero (for example, it is sufficient if the vibration acceleration is equal to the gravitational acceleration). In such a case, by setting the total eccentric moments of both the A and B groups to be substantially equal, it is possible to construct a vibrating machine having practical value.

According to the fourteenth aspect of the present invention, the rotational driving and the phase control of the plurality of eccentric weights can be easily performed with a simple mechanism. That is, when the invention of claim 13 is applied to configure two groups A and B each including a plurality of eccentric weights, the degree of freedom in designing the eccentric weights in each group increases. As described above, since the number of eccentric weights is large (at least four), the drive mechanism and the phase difference control mechanism for these many eccentric weights tend to be complicated. Therefore, in addition to the structure of the invention of claim 13, when the invention of claim 14 is applied to rotate and drive the eccentric weights for each group and the phase control is performed for each group, an eccentric weight composed of two eccentric weights is generated. It becomes possible to drive and control by a simple mechanism similar to the rotation drive / phase control mechanism of the shaker.

[Brief description of drawings]

FIG. 1 shows a main part of an eccentric weight type vibration oscillating machine according to the present invention,
(A) is the center line XX of the eccentric weight gear in one embodiment.
FIG. 4B is an exploded perspective view schematically illustrating the B of FIG. 3 by bending it by an angle φ around the Z axis, and FIG. 6B is a partial cross-sectional view illustrating an eccentric weight and a supporting / transmitting member thereof in an embodiment different from the above. .

FIG. 2 is shown for explaining the phase control of the eccentric weight in one embodiment of the present invention, in which (A) shows the fixed eccentric weight and the movable eccentric weight in symmetrical positions with respect to the rotation axis. It is a schematic diagram depicting a reference state in which the excitation force is zero,
(B) is a schematic diagram illustrating a state where the movable eccentric weight is rotated from the reference state by an acute angle θ and the excitation force is maximized,
(C) is a schematic diagram illustrating a state in which the vibrating force is moderately adjusted.

FIG. 3 is an explanatory view of a rotary type vibration exciter in which eccentric weights are attached to each of four rotating shafts.

FIG. 4 is an explanatory diagram showing transmission of ground waves and underground waves in a pile driving work using a vibration device.

FIG. 5 is a table showing time-rotation speed for explaining a resonance phenomenon in a vibrating pile driving work.

6A and 6B are schematic views for explaining the operation of the four-shaft, four-weight exciter shown in FIG. 3 described above, and FIG. 6A is a diagram in which the eccentric weight descends as in FIG. Represents the state of
(B) shows a state in which the weight is rotated by about 90 degrees, and (C) shows a state in which the weight is further rotated by about 90 degrees.

FIG. 7 is a view for explaining a known technique of changing the vibrating force by a combination of two eccentric weights, where (A) shows that the two eccentric weights exert the maximum vibrating force. (B) is a schematic diagram showing a state where the vibrating force is medium, (C) is a schematic diagram showing a state where the vibrating force is slightly small, and (D) is a schematic diagram showing a state where the vibrating force is slightly small. It is a schematic diagram showing a state.

FIG. 8 is a schematic diagram of a mechanism in which a fixed eccentric weight is fixed to a common rotation shaft and a movable eccentric weight can adjust a relative rotation angle position with respect to the common rotation shaft.

FIG. 9 shows a fixed eccentric weight and a movable eccentric weight arranged on a common axis so as to increase or decrease the vibrating force as shown in FIG. 8 described above. It is a perspective view which shows the conventional example of a shaker.

10 is a view for explaining the relationship between the rotating shaft, the fixed eccentric weight, and the movable eccentric weight in the conventional exciter having the adjusting mechanism shown in FIG. 9 shown in FIG. 1) is an external perspective view partially cut and drawn, and FIG. 2B is a schematic view illustrating a portion viewed in a direction parallel to the rotation axis.

FIG. 11 is a cross-sectional view showing the entire rotation system including the drive system of the eccentric weight type vibration oscillating machine shown in FIG. 11B described above, in which the components of the phase control mechanism are indicated by chain lines. FIG.

FIG. 12 is a horizontal vibration exciter including two sets of vibration oscillating units each including a fixed eccentric weight fixed to a rotation shaft and a movable eccentric weight rotatably attached to the rotation shaft. FIG.

FIG. 13 is a schematic diagram showing a relationship between a center of gravity of a fixed eccentric weight and a movable eccentric weight with respect to a rotation axis X and an attachment point.

[Explanation of symbols]

1: Exciter case, 2, 2A to 2D: Rotating shaft, 3, 3
A to 3D: eccentric weight, 4, 4A to 4D: transmission gear for synchronous rotation, 5: crane boom, 6: vibrating device (vibrator), 7: pile, 8: private house, 9, 9A, 9B ... Fixed eccentric weight, 10, 10A, 10B ... movable eccentric weight, 10a-1
0c: Adjustable position of movable eccentric weight, 11: Drive pulley,
12 ... Female screw hole, 13 ... Dowel pin, 14 ... Set bolt, 15 ... Hexagon wrench, 16 ... Fixed eccentric weight, 17 ... Movable eccentric weight, 18 ... Tubular outer shaft, 20 ... Fixed eccentric weight gear, 21 ... Eccentricity Weight gear shaft, 22 ... Movable eccentric weight gear,
26 ... Gear boss, 30 ... Inner shaft.

Claims (14)

[Claims] 1. A center line of a rotation axis is defined as an X axis, and two eccentric weights having equal eccentric moments with respect to the X axis are arranged, and the center of gravity of each of the two eccentric weights is perpendicular to the X axis. The two eccentric weights while controlling the phase difference between the two eccentric weights.
An eccentric weight-type vibration generation / control method, characterized in that each eccentric weight is rotated around the X axis. 2. The maximum state in which the two eccentric weights can relatively rotate about the X axis is limited to about 60 degrees, and both eccentric weights are symmetrically positioned with respect to the X axis. The eccentric weight type vibration generation / control method according to claim 1, wherein the phase difference between the two eccentric weights is changed within a range of about 30 degrees from the reference state. 3. A vibration acceleration generated when the phase difference between the two eccentric weights is brought close to a standard state to reduce the total eccentric moment amount of the two eccentric weights, and the gravitational acceleration is defined as substantially gravitational acceleration. Alternatively, the eccentric weight type vibration generation / control method according to claim 1 or 2, wherein the vibration is smaller than the gravitational acceleration. 4. A tubular outer shaft having an eccentric weight different from the above is fitted to an inner shaft having an eccentric weight attached so as to be relatively rotatable, and the two eccentricities are provided. The eccentric weight-type origin is characterized in that the moments of the weights are equal to each other, and the center of gravity of each of the two eccentric weights is located on the same plane perpendicular to the inner and outer axes. Shaker. 5. Two eccentrics, each of which has an eccentric weight fixed thereto, are rotatably supported by the same gear shaft, and the two eccentrics fixed to each of the two gears. The eccentric weight type vibration is characterized in that the eccentric moments of the weights with respect to the gear axis are equal to each other, and the rotation loci circles of the centers of gravity of the two eccentric weights are located on the same plane. Machine. 6. Two motors for individually rotating and driving each of the two eccentric weights are provided, and the two motors are provided with means for controlling mutual rotational phase difference. The eccentric weight type vibration oscillating machine according to claim 4 or 5, wherein 7. A motor for rotating and driving the two eccentric weights is provided, and a means for controlling a rotational phase difference between the two eccentric weights is provided. The eccentric weight type vibration oscillating machine according to claim 4 or 5, which is characterized. 8. An even number of sets of fixed eccentric weights and movable eccentric weights that have equal eccentric moments and share a rotating shaft are provided, and the fixed eccentric weights of each set mutually act as gears. The movable eccentric weights of each set are also connected so as to rotate synchronously via gears, and the fixed eccentric weights connected to each other are also connected to each other. The eccentric weight according to claim 7, further comprising means for relatively rotating the connected movable eccentric weight and means for preventing the relative rotation. Type exciter. 9. A total of three eccentric weights including two eccentric weights having the same eccentric moment and one eccentric weight having an eccentric moment equal to the sum of the eccentric moments of the two eccentric weights. Are arranged with their central axes of rotation aligned, and the position of the total center of gravity of the two eccentric weights and the position of the center of gravity of the one eccentric weight are on the same plane perpendicular to the central axis. Eccentric weight-type exciter characterized by being located above. 10. A drive mechanism for rotating a total of three eccentric weights including the two eccentric weights and one eccentric weight in the same direction, and the two eccentric weights. The weights are driven in conjunction with each other so as to rotate while maintaining the same rotation phase, and a control mechanism for adjusting the phase difference between the one eccentric weight and the two eccentric weights is provided. Characterized by that
The eccentric weight-type exciter according to claim 9. 11. An eccentric weight is provided, comprising one inner shaft and two tubular outer shafts fitted to the inner shaft so as to be rotatable relative to the inner shaft. The eccentric weight type vibration exciter according to claim 10, wherein the two eccentric weights are attached to the one inner shaft, and the two eccentric weights are respectively supported by the two tubular outer shafts. . 12. A mechanical device so that the rotational phase difference between the one eccentric weight and the two eccentric weights or the rotational phase difference between the inner shaft and the tubular outer shaft does not exceed 60 degrees. The eccentric weight type vibration exciter according to claim 11, wherein the eccentric weight type vibration exciter has a structure in which the phase difference is controlled between 0 and 30 degrees. 13. A plurality of eccentric weights of group A are arranged with respect to a common rotation center line X, and a plurality of eccentric weights of group B are arranged with respect to the rotation center line X. The total eccentric moments of the plurality of eccentric weights of the A group with respect to the X axis and the total eccentric moments of the plurality of eccentric weights of the B group with respect to the X axis are equal to or substantially equal to each other. An eccentric weight type vibrator. 14. A plurality of eccentric weights of the A group are fixed to a rotary shaft and are rotationally driven by a drive means of the A system, and the plurality of eccentric weights of the B group are the above. Is rotatably supported relative to the rotation axis of the system A, and is rotationally driven by the drive unit of the B system. The rotational phase difference between the drive unit of the A system and the drive unit of the B system is The eccentric weight-type exciter according to claim 13, which is controllable.