DE4439170A1 - Ram vibrator to produce harmonised vibrations - Google Patents

Abstract

The vibrator system has the total maximum centrifugal moment (M) is divided into two out-of-balance body groups. The total centrifugal moment MG1 and MG2 of the two groups is distributed over three axes having three partial out-of-balance bodies. The minimal position stop is produced by the hydraulic positioning process of a hydraulic cylinder of an adjustment device to a preset third position lying between two piston end points. The adjustment of the relative position angle beta is actuated by an overlay drive (55).

Description

The invention relates to a ram vibrator for generating directional vibrations by means of rotating unbalance bodies, in which the size of the total centrifugal moment M _Res resulting from the partial centrifugal moments M _{T of} the individual partial unbalance bodies can be adjusted. The adjustment technology to be used in this case includes the principle of action in which the adjustment of M _{Res is} achieved by adjusting relative adjustment angles β, which can be defined between partial unbalance bodies running at the same rotational speed. In addition, the Gat device of the vibrators affected here should be characterized in that the vibrators are equipped with at least three unbalanced rotation axes arranged in a plane parallel to the direction of vibration.

In the latter three unbalance vibrators, the simplest types of embodiment that cannot be adjusted with regard to the resulting centrifugal moment have three instead of usually two unbalanced shafts equipped with partial centrifugal moments. The maximum resulting total centrifugal moment M is divided in such a way that the middle shaft has a share of M / 2 and the two outer waves have shares of M / 4 each.

The direction parallel to the plane common to the three axes However, only then does the directional oscillating movement take place if the three partial unbalance bodies are synchronized in this way (approx by a gear transmission) that at that angle of rotation at which the vectorial sum of all partial centrifugal moments, and thus also the result centrifugal force has the value zero, and at which the three partial Centrifugal moments are aligned perpendicular to the direction of vibration, the two external partial centrifugal moments on the one hand and the average partial centrifugal moment are aligned in opposite directions.

Due to the arrangement and dimensioning of the three parts due to the balancing body, this is the at least 6 bearings of the necessary three Shaft-absorbing vibrator housing is functional in its design predetermined that it has a clear longitudinal extension, and inevitably takes the form of a shoebox, the Longitudinal extension in the direction of vibration.  

This type of vibrator is well suited to the combination of a corresponding vibrating ram with a leader serving as a carrier device, where at the center of gravity of the mainly defined by the housing mass vibrating "dynamic mass" m _Dyn can be kept relative to the leader of the leader with the desired low projection .

If a change in the resulting centrifugal moment is desired in these known simple three-unbalance vibrators, it is still necessary to manipulate the individual partial centrifugal moments by hand when the vibrator is stopped. However, there is a desire on the part of the user to provide these ramming vibrators with an adjusting device, by means of which the resulting total centrifugal torque M _{Res can be changed} during the rotation of the unbalanced shafts from the value M _Res = 0 to the value M _Res = M.

Such an adjustability is to be used according to the usual practical requirements already today with other types of ram vibrators to practice an operating mode in which the ram vibrator can be used with a working vibration frequency f _o which is above the resonance frequency of the ground without it having to pass through the Rotational frequency range between the rotational frequency f = 0 and the rotational frequency f _o leads to an inadmissible resonance excitation of the floor. The avoidance of a resonance excitation when starting and lowering the rotational frequency is achieved in that the resulting centrifugal torque is set to the value M _Res = 0 during this operating phase, which is synonymous with the adjustment of the relative setting angle β by the adjusting device the value β = 0 °.

Adjustment devices for adjusting the resulting centrifugal moment M _Res of ramming vibrators using the principle of adjusting relative setting angles β between partially rotating partial centrifugal elements have become known in a wide variety of designs, e.g. B. demonstrably the publications EP-PS 0 506 722 B1, DE-OS 41 18 069 A1 and DE-OS 43 01 368 A1.

The described by the aforementioned publications, as well as in Adjustment devices described in other publications are all However, all tailored to another genus by Richtschwin gladly, namely to those in which the non-adjustable directional rocker  simplest design over two of the same size and synchronously in opposite directions running unbalance body, the direction of which is directed Vibration perpendicular to one of the at least two axes of rotation legible level, and here is an essential distinction Characteristic to the genus of vibrators according to the invention.

The transferability of the known adjustment techniques measured on a three-unbalance vibrator will:

With an adjusting device for the relative setting angle β according to the EP PS 0 506 722 B1 are practically a first and a second two-shaft The simplest directional transducer with parallel alignment of the shafts both directional swings arranged one above the other. When adjusting the Relative pitch angle β becomes the complete first two-shaft directional oscillator against the complete second two-shaft directional oscillator relatively by one Adjustment angle β adjusted. An exact directional oscillation results. The Load on the bearings remains unchanged (assuming a constant speed) depending on the set relative positioning angle β constant.

The partial unbalance bodies of each two-shaft directional oscillator are over tooth wheels synchronized, such that this gear connection Reaction torque MR and the torque for the useful work little at least one of the partial centrifugal moments must be supported. (To the formation and effect of the reaction torque MR see explanations in the mentioned EP-PS).

The transfer of this adjustment principle of the stacked arrangement two simple designs on a three-shaft vibrator is possible, what but because of the 6 waves lying in a row to one not ak acceptable large longitudinal extension of the vibrator housing leads.

The publication DE-OS 41 18 069 A1 teaches the partial centrifugal moments or they embody partial unbalance bodies of two simple two-shaft alignments to arrange the vibrators next to each other, in such a way that the ent speaking part unbalance coaxial and arranged on a shaft are. When adjusting the relative setting angle β is also in this Trap the complete first two-shaft directional oscillator against the complete one second relatively adjusted by an adjustment angle β.  

In this case, a true directional oscillation results for the setting M _Res = M, however, as the value of M _Res <M decreases, a wobble moment occurs. This wobble moment can be easily explained for the setting M _Res = 0 or relative setting angle β = 0 °, in the situation in which the partial centrifugal moments are aligned in the direction of vibration.

In this case too, the reaction torque of at least one part Centrifugal torque and the torque for the net power over the toothed wheels which also synchronizes the two partial unbalance body of each gear shaft gear serving every two-shaft directional oscillator be transmitted.

The transfer of the described adjustment principle of the side by side Arrangement of two simple versions of a two-shaft directional oscillator on a three-shaft vibrator is also possible. In compliance with the Adjustment position β = 0 ° indicates the swinging movement with the Main vibration direction omitted component also the value zero on what is also used to suppress the excitation of the ground Leads resonance frequency. The tumbling moment occurring in this situation leaves a swinging motion component in the direction of the axis direction of the unbalance body arise, which affects the leader transmits and thus looks very disadvantageous.

The route shown in DE-OS 43 01 368 A1 dispenses with any Torque transmission through gears. In contrast, every partial unbalance is body with its own actuator and drive motor, of which the useful torque required for the respective unbalance body and reaction torque is applied, for which it is of a special kind the interconnection of the motors.

The gears 204 and 204 'shown in Figs. 2 and 3' serve only egg ner safety function in the event that external interference forces should occur, which are greater than those derived from the inertial forces of the dynamic mass and transferred to the unbalanced masses self-synchronization forces.

From Fig. 3 it can be seen that the unbalanced masses 203 (and 204 ) assigned to the motors are divided into two equal parts 201 a, 201 b, which che with an axial distance from each other on the half shaft 217 (or 217 ') are arranged. In this axial clearance between the two same parts, a further average unbalanced mass 205 (or 205 ') is rotatably mounted on the half shaft 217 (or 217 ').

The two middle unbalanced masses have 3 special functional properties assigned to units:

• - Each mean unbalanced mass 205 ( 205 ') is driven by its own motor, by which the relative angular position to the two sliding parts 201 a and 201 b ( 201 a', 201 b ') is determined,
• - The coaxial arrangement is chosen in order to limit the relative Setting angle β between the unbalanced masses of two motors by mecha to be able to bring about attacks at all, and
• - The direction of rotation of the unbalanced mass 205 ( 205 ') and the two identical parts 201 a, 201 b ( 201 a', 201 b ') is in the same direction, which is predetermined by the impact function.

The advantage described in column 12, line 50 ff. Of a complete load relief of the shaft bearings with a set value of zero for the relative setting angle β cannot, however, be realized with the roller bearings shown in the drawing, because experience has shown that these bearings relieve pressure below a certain minimum Radial force F _{R, M} quickly become unusable. The construction shown in FIG. 3 is also disadvantageous in that the two partial shafts 216 and 217 have to be supported one inside the other via two roller bearings. With regard to the type of stress that occurs, this leads to dimensioning problems in the case of a design for permanent operation of the bearing.

A transferability of the adjustment principle of DE-OS 43 01 368 A1, ge characterized by a transmission of both the adjustment torques as also the reaction torques while keeping the angle β constant counteracting actuating torques, as well as the working torque elements directly from the actuator and drive motor to the assigned imbalance body per, on three-wave directional oscillator is not given. Against it speaks especially:

• - The division of the parts required for a three-shaft directional oscillator Centrifugal moments with different proportions on three shafts with various resulting physical effects and consequences, such as B. Tue. dimensioning regulations for the motors to be used,  
• - the previously unknown behavior of a three-wave direction schwingers on the question of whether, and if so, with what effects Reaction torques occur, as well
• - The fact that a total of 6 actuators and drive motors are installed should be.

The transferability of the adjustment principle is also not given if the conditions specified by the angle stop are not should be accepted.

The invention is therefore based on the following object: It is to create a ro bustte and durable adjusting device for adjusting the resulting centrifugal torque M _Res on three-shaft ram vibrators by changing the relative setting angle β between several partial imbalance bodies. The possible disadvantages described above, such as the occurrence of wobble moments, the occurrence of inaccurate directional vibrations, the occurrence of harmful bearing loads and the forced formation of vibrator housings with an extremely large longitudinal extension, are to be avoided, and at the same time the prerequisite for the use of Roller bearings are created.

Furthermore, the solution with its basic mechanical structure should do so be suitable to alternatively make the adjustment of the relative setting angle β men, on the one hand through the use of a superposition gear, about, as shown in DE-OS 41 18 069 A1, and on the other hand by An use of at least two adjustment and drive motors, which at Maintaining a predetermined relative setting angle β always one Have to implement apparent power, such as in EP-PS 0 506 722 B1 Are defined.

The solution to this problem is through the teaching of claim 1 de finishes. Advantageous developments of the invention are the Un Described claims.

The feature contained in claim 1, according to which both Unwuchtkör per groups should have the same direction of rotation not obvious. Due to the special mode of action of a three-wave Dirtschwingers conditional, there is also the possibility that at to let the unbalance body groups rotate in opposite directions. This even has  the advantage that a setting to bring about a zero Vibration amplitude no problems of insufficient minimum radial forces for Result in roller bearings.

The invention nevertheless prefers the alternative solution with the same direction Rotation of the unbalance body groups, since this is done in several ways better conditions in terms of bearing friction losses can be, although additional measures to ensure a the minimum radial force acting on the bearings must be accepted sen.

The development of the invention according to claim 2 creates, among other things, the prerequisite for the use of roller bearings, which should be preferred because of their egg property of a high load-bearing capacity and at the same time a high permissible speed at ramming vibrators according to the invention operating at their rotational frequency above the ground resonance frequency. The use of these bearings requires that a minimum radial force F _{R, M} depending on the bearing capacity of the bearing is not less than the minimum load on the bearings. In the case of vibrators that are not regulated with respect to the resulting centrifugal torque and in other applications of these bearings, where sufficient shaft weights or other loads are always present, this question does not matter.

In ram vibrators because of the low masses (weights) he generated high centrifugal forces and because of the bearings to be used with high load ratings, the weight forces borne by the bearings of Wel len and gears are far from sufficient to the minimum radial force F _{R, M} to create. On the other hand, however, in a mass distribution according to claim 1, the reduction of the resulting centrifugal element M _Res to the value zero also means that the centrifugal bearing load assumes the value zero.

According to the teaching of claim 2, an artificial minimum radial force F _{R, M} is therefore provided. In the alternative solution, according to which it is provided that the minimal resulting centrifugal moment M _Res provided in practical use of the ramming vibrator does not drop below the value M _{R, M} , in order to increase the value of M _{R, M} with that for F _R, To be able to generate _M required centrifugal force, the invention draws on the knowledge that with residual vibration amplitudes generated by M _{R, M there} is no longer any danger of a noticeable excitation of resonance vibrations of the ground.

It can be shown that if the highest operating speed is observed, the necessary residual centrifugal torque M _{R, M can be} limited to approximately 5% of the maximum centrifugal element M, which also means that the vibration amplitude A _{R, M} = M _{R, M} / m _{Dyn is} reduced to 5%.

The special mode of operation of a three-shaft directional vibrator known to the person skilled in the art results in a directional oscillation symbolized by arrow 70 with an oscillation direction perpendicular to the axes of rotation (for example 20 ) and parallel to a plane which can be laid through all axes of rotation. This directional oscillation movement remains constant with regard to its oscillation direction even with all changes in the resulting centrifugal moment M _Res .

The invention is illustrated by an example with the help of a drawing explained. The drawing shows a schematic of a vibrator cell in the Longitudinal section through all three unbalance axes with equipment which is suitable for performing two different adjustment techniques.

The vibrator housing 1 has six roller bearings 2/2 '; 3/3 'and 4/4 ', in which the three unbalanced shafts 5 , 6 and 7 are mounted. Each unbalance shaft carries a one-piece part unbalance body 8 ; 9 ; 10 and each have a two-part partial unbalance body 12/12 '; 13/13 ′; and 14/14 ', the items part-part eccentric body can be mentioned. On each unbalance shaft is a partial unbalance body 12/12 '; 13/13 ′; 14/14 'rotatably connected to the Un balancing shaft, while the other part unbalance body 8 ; 9 ; 10 by means of a needle bearing 15 ; 16 ; 17 is rotatably mounted relative to the unbalanced shaft or relative to the other partial unbalanced body.

The centrifugal moments represented by the partial unbalance bodies are of equal magnitude on one and the same unbalanced shaft. If one sets the sum of all partial centrifugal moments of all partial unbalance bodies = M, then the centrifugal torque components are distributed over the unbalanced shafts in such a way that the average unbalanced shaft (central axis 19 ) accounts for the M / 2 component and the two outer unbalanced shafts ( outer axes 20 ; 21 ) have proportions of M / 4 each.

The axial distances between the partial and unbalanced bodies are on each unbalance  shaft chosen such that the gravity definable during rotation point planes of the two partial unbalanced bodies in axial extension equally far from the center of gravity level of the middle unbalance body are removed. Depending on which mode of operation will be explained later comes into question, the centrifugal moments of the partial unbalance body The unbalance shaft must be the same size or the same size.

The total maximum centrifugal moment M is distributed over two imbalance body groups. The three sub-unbalance bodies belonging to an unbalance body group are divided between the three unbalanced shafts and connected or synchronized with one another by a gear train with the three gear wheels 22/23/24 or 25/26/27 . The synchronization of the partial unbalance bodies carried out by the gear train causes the partial centrifugal moments of the outer axes, which can be understood as vectors, to always be rectified, while in comparison the partial centrifugal moment of the central axis is aligned in exactly the opposite direction.

The rotationally fixed connections between gear wheels and unbalanced bodies on the one hand and between unbalanced bodies and unbalanced shafts on the other hand are indicated by dash-dot lines 30 and 32, respectively.

The resulting centrifugal force F _Res acting on the vibrator housing 1 or on the entire associated dynamic mass m _Dyn is (apart from the speed) dependent on the resulting centrifugal torque M _Res which can be understood as a vectorial sum of all partial centrifugal moments. The resultant centrifugal torque M _Res can be continuously adjusted in its value between a maximum value M _Res = M and a minimum value by changing the relative setting angle β of the gears of the two gear trains to one another or the two partial centrifugal moments of an unbalanced shaft to one another.

The unbalanced shafts 5 and 6, which are connected in a rotationally fixed manner with partial unbalance bodies of different group membership, can be driven by hydraulic motors 40 and 42 , whereby in addition to the series connection shown here, a parallel connection of the motors is also possible.

In an additional housing 61 fastened to the vibrator housing 1 by means of screws 50 , a superposition gear 55 is rotatably supported in bearings 52/53 , with an input gear 56 meshing with the gear 25 of the one gear train and with one meshing with the gear 22 of the other gear train Output gear 57 .

By accommodated in the superposition gear 55 , via rotary feedthroughs 58 and 59 bilaterally pressurized with a pressure fluid hydraulic piston with two mechanical position end stops, the gears 56 and 57 are adjustable in their relative angular position even during the rotation of the superposition gear in a manner known to the person skilled in the art . With the relative adjustment of the gears 56 and 57 , the resulting centrifugal torque M _{Res is} proportional with adjustable bar.

On the partial unbalance body 8 , a nose 63 is attached, against which, in a position in which the resulting centrifugal moment is minimal, the front part of a stop pin 65 pressed into the gear 22 strikes and thus prevents a further change in the relative setting angle β . This stop function is only provided as an alternative and can be omitted or can also be replaced by the position end stop of the hydraulic piston contained in the superposition gear 55 . The proposed stop function also indicates that the rotation of the partial unbalance body which serves to generate the centrifugal force is in the same direction.

The following applies in common to the two possible operating modes to be described below: As already described, the invention provides for the possibility of setting a residual centrifugal torque M _{R, M} , with the aid of which a sufficiently large minimum radial force F _{R, M} can be generated. The relative setting angle β (z. B. β = 0 °), at which the residual centrifugal element M _{R, M is} set, is produced by inducing a "minimum position stop".

For both modes of operation, the minimum position stop can be a mechanical fixed stop, as previously described. Alternatively, in the operating modes, the minimum position stop can also be brought about by a positioning operation carried out with the actuating actuator or with the actuating actuators. When using a Verstelleinrich device with the participation of the superposition gear 55 is hen hen, that the existing in the superposition gear hydraulic piston except in the end positions can still be held in a third predetermined position, which z. B. bewerkstel by using two pistons.

Operating mode 1

The drive for rotation of the partial unbalance body is carried out by a suitable, known to the person skilled in the art hydraulic supply of the two hydraulic motors 40 and 42 , which, for. B. also - as shown in the drawing - can be connected in series. The services implemented in the hydraulic motors cover the need for the useful power to be delivered by the ram vibrator, as well as the requirements for all power losses that occur.

A change in the resulting centrifugal moment is done by moving the hydraulic piston contained in the overlap transmission 55 in different positions by different bilateral action and thus the gears 56 and 57 are brought into a different relative angular position. To move to a piston end position or the stop 63/65 , it is also sufficient to open the hydraulic piston only via one of the rotary unions 58 or 59 .

Operating mode 2

In this mode of operation, the superposition gear 55 is not required and is assumed to be removed by imagining the entire additional housing 61 as being removed from the vibrator housing 1 .

Hydraulic motors 40 and 42 also cover the requirements of the vibrator with regard to useful power and power loss in operating mode 2. While in mode 1, the apparent power tapped from the gear 25 of one unbalance body group was passed through the superposition gear 55 and via the gear 57 of the other unbalance body group (with the opposite sign for the direction of the torque) was fed back, the one must be set at a Relative setting angle 0 ° <β <180 ° apparent power of both imbalance groups can be additionally applied by the hydraulic motors 40 and 42 . Thus, the hydraulic motor 40 and the hydraulic motor 42 must additionally apply the apparent power for the gear units 22/23/24 and 25/26/27 assigned to the partial unbalance body.

The change in the relative setting angle β or the change in the resulting centrifugal torque M _Res takes place in operating mode 2 in that, in a manner known to the person skilled in the art, the rotation angles of the two hydraulic motors also during the operating rotation of the unbalanced shafts according to predetermined values for the Relative position of both angles of rotation can be regulated or controlled.

In the shown series connection of the motors, the influencing of the relative position can be made very simply by influencing the pressure in the pressure line between the two motors by an external grip (symbolized by arrow 80 ).

A minimum position stop can also be produced here by using the mechanical stop 63/65 . This is particularly recommended if the same (or comparable) stop elements can also be used to limit the relative setting angle β _max responsible for the maximum resulting centrifugal torque M _{Res, max} .

Claims (11)

1. ramming vibrator with a partial unbalance body rotating on a rotating middle and two outer axes such that a centrifugal moment M is distributed so that a share of M / 2 on the central axis and a share of M / 4 on each outer axis is omitted, which Partial unbalance bodies embody corresponding partial centrifugal moments, and of which axes of rotation at least two define a plane parallel to the direction of vibration, characterized by the combination of the following features,

• The total maximum centrifugal moment M is distributed over two imbalance body groups,
• - The total centrifugal moments M _{G, 1} and M _{G, 2 of} each unbalance body group are distributed with the three partial centrifugal moments embodying three partial Unwuchtkör bodies on three axes, the partial unbalanced bodies of an unbalanced body group with respect to their angle of rotation by at least one egg n gear train are synchronized positively per imbalance body group,
• - The partial centrifugal torques belonging to a rotation axis belonging to different groups are arranged coaxially on the axis with respect to their pivot points,
• - At least in the middle axis, the partial unbalance bodies are divided on the axis in such a way that the partial unbalance body of the one unbalance body group is divided into two partial partial unbalance bodies, which are arranged coaxially with a space in between, with the space in the space other part-unbalance body of the other unbalance body group is housed coaxially, and the two part-part unbalance body on the one hand and the other part-unbalance body on the other hand are rotatable relative to each other.
• - Both imbalance body groups have the same direction of rotation,
• - The purpose of changing the resulting centrifugal torque M _{Res of} all partial centrifugal forces feasible adjustment of the relative setting angle β is caused in that the coaxially arranged gears of the gear sluggish two different imbalance groups are adjusted relative to each other with a twist angle.

2. ram vibrator according to claim 1, characterized by the combination of the following features,

• - At least in the middle axis, the centrifugal forces of the unbalanced parts are transferred to the vibrator housing, the bearing roller and bearing,
• - At least when a minimum position stop is reached, at least a minimum radial force F _{R, M} acting on the bearings is generated for the bearings of the central axis, either by the centrifugal force of a residual centrifugal torque M _{Res, An} , <0 , or by an auxiliary force applied radially to the bearing shaft via an auxiliary bearing,
• - The minimum position stop is either brought about by mechanical stop forces within the adjusting device for adjusting the relative setting angle β or between two components rotating together on one of the axes, or is brought about by forces generated by hydraulic pressures during hydraulic positioning processes.

3. A ram vibrator according to claim 1 in conjunction with claim 2, characterized characterized in that the minimum position stop by a hydraulic positioning process of a hydraulic cylinder of an adjusting device at a predetermined one lying between two piston end positions third position is brought about. 4. ram vibrator according to one of claims 1 to 3, characterized in net that the adjustment of the relative setting angle β is effected by a Superposition gear, the input of which with a gear train Imbalance body group and its output with a gear train other unbalance body group is connected to transmit torque. 5. ram vibrator according to one of claims 1 or 2, characterized is characterized in that the adjustment of the relative setting angle β is effected by at least two hydraulic actuators and drive motors, one of which is Mo torrotor with a gear train of an imbalance group and de other motor rotor with a gear train of the other imbalance bodies per group is connected to transmit torque.   6. ram vibrator according to claim 1 in conjunction with claims 2 and 5, characterized in that a minimum position stop by a hydraulic positioning process with the participation of two with their Roto ren is always brought with rotating servo and drive motors. 7. Ramming vibrator according to one of claims 2 to 6, characterized in that the residual centrifugal torque M _Res, set when the minimum position stop is reached _{, is} approximately 5% or more of the maximum existing centrifugal torque M. 8. ram vibrator according to one of claims 2 to 6, characterized in net that the idle of the ram vibrator when reaching the minimum digit residual vibration amplitude which occurs about 5% or more of the same dynamic mass with the maximum centrifugal torque set ment M is the resulting oscillation amplitude. 9. A ram vibrator according to any one of claims 2 to 8, characterized in that the residual centrifugal torque M _Res, present when the minimum position stop is reached _{, is set} as a function of the speed of the unbalance body driven. 10. Ramming vibrator according to one of claims 2 to 9, characterized in that at least on the central axis, the residual centrifugal torque M _Res, is generated in that the partial centrifugal moment of a Un imbalance group is greater than the partial centrifugal torque of other unbalanced mass group. 11. Ramming vibrator according to one of the preceding claims 1 to 10, characterized in that the total centrifugal moment M _{G, 1} and M _{G, 2 of} both unbalance body groups half on the partial unbalance body of the central axis and one quarter each on the outer axes is divided.