Device for vibration decoupling between two systems and a working machine

Abstract

Device for vibration decoupling between two systems (2, 4) in the form of spring-mass oscillators, one system (2) of which is assigned to a motion machine and the other system (4) to an operator acting on the motion machine, which at least partially performs movements about a transverse axis (Q) during traversing movements of the motion machine and thereby vertical movements in the direction of a vertical axis (z) with an absolute vertical velocity (v) z1,1 ) is subject to, which serves as an input variable for control and / or regulating devices that control a damping system (8) of one (2) and / or other (4) system to compensate for the vibrations, characterized in that the respective pitching movement of the other system (4) is detected by means of at least one gyroscope, the respective measured value (ω1), preferably amplified only by a predefinable factor (L1), the absolute vertical velocity (v z1,1) as an input variable.

Description

[0001] The invention relates to a device for vibration decoupling between two systems in the form of spring-mass oscillators, one of which is assigned to a motion machine and the other to an operator acting on the motion machine, which at least partially performs movements about a transverse axis during the motion machine's traversing movements and is subject to vertical movements in the direction of a vertical axis with an absolute vertical velocity, which serves as an input variable for control and / or regulating devices that control a damping system of one and / or the other system to compensate for the vibrations.

[0002] From EP 1 018 445 A2, an assembly is known that comprises a first element, a second element, and a controllable suspension system. The suspension system includes a controllable damper arranged between the first and second elements and a control system comprising an accelerometer for detecting acceleration values ​​of the first element and a displacement sensor for detecting values ​​of the distance between the first and second elements. The values ​​detected by the accelerometer are integrated by means of an integrator, thereby calculating the absolute velocity v. abs of the first element, and the values ​​detected by the displacement sensor are differentiated using a filter, which determines the relative velocity v. rel between the first and the second element.

[0003] The control system also features a control unit which, using a control strategy, inputs the absolute velocity v. abs and the relative velocity v rel a desired damping force F is supplied desired of the controllable damper. According to the control strategy, in particular, when the signal v is a product of the signal v abs and the signal v rel of greater than or equal to 0 the desired damping force F desired equivalent to a product of an amplification G, the signal v abs and a function that depends on the absolute velocity v abs and the relative velocity v rel is dependent.

[0004] In a preferred embodiment, the first element comprises a seat and the second element comprises a frame to which the seat is connected.

[0005] Accelerometers regularly exhibit a so-called offset, which is integrated when the values ​​recorded by the accelerometer are integrated and results in a drift of the signal of the determined absolute velocity v. aps This results in an error in this signal. Furthermore, the signal is the relative velocity v. rel The absolute velocity v, which is determined by deriving the signal from the displacement sensor, is regularly subject to noise. When using a faulty signal, the absolute velocity v... abs and a noisy signal of relative velocity v rel The signal is accordingly the desired damping force F determined from these signals. desired equally faulty and / or noisy.

[0006] In practice, the drift or error of the absolute speed is corrected by high-pass filtering, and noise reduction of the relative speed is achieved by suppressing noise using low-pass filtering. However, each filtering of the respective speed, regardless of the other filtering, leads to a distortion of the signal for that speed in the form of a phase shift of the determined speed signal, which must be corrected in each case.

[0007] Based on this state of the art, the invention aims to improve the known device in such a way that, with a simple design, it decouples one system from another system in such a way that, in the event of vibrations in one system, the other system remains vibration-free by compensating for these vibrations with high accuracy.

[0008] This problem is solved by a device for vibration decoupling with the features of claim 1.

[0009] According to the characterization of claim 1, the respective pitching movement of the other system is detected by means of at least one gyroscope, the respective measured value of which, preferably amplified only by a predefinable factor, yields the absolute vertical velocity as an input variable for the subsequent system control.

[0010] Because the device according to the invention uses a gyroscope to determine the angular velocity of the other system, the angular velocity can be obtained directly from the sensor, without any prior complex calculations. Furthermore, according to the invention, the absolute vertical velocity is derived directly from the angular velocity detected by the gyroscope, particularly with only a predefinable factor applied, so that only a minimal amplification is necessary. In contrast to the prior art, obtaining the absolute velocity does not require integration of the measured values ​​acquired by the accelerometer, which introduces the accelerometer's offset and results in a drift in the absolute velocity.

[0011] The simple design of the device and the few necessary components result in an easy-to-manufacture device and, by providing only a simple amplification if necessary, a less error-prone determination of the absolute vertical velocity, which increases the accuracy of the vibration compensation.

[0012] The gyroscope according to the invention can be designed as a micro-electro-mechanical system (MEMS), i.e., as a micromechanical sensor, with in particular at least one plate that is selectively excited to vibration and is based on the Coriolis principle. In such sensors, the Coriolis force acts on the MEMS when the gyroscope rotates, and the MEMS's response to this excitation is individually detected in three dimensions. Micromechanical sensors have the advantage of being readily available and inexpensive. Preferably, the gyroscope integrated into the "HIT 1500" product from HYDAC Electronic GmbH is used.

[0013] In a preferred embodiment, the other system can perform rolling movements about its longitudinal axis during the traversing movements of the moving machine and is subject to further vertical movements in the direction of the vertical axis with a further absolute vertical velocity, which serves as a further input variable for the control and / or regulating devices. In this way, in addition to the pitching movements of the other system about its transverse axis, rolling movements of the other system about its longitudinal axis can also be compensated by the device according to the invention. The further absolute vertical velocity can be superimposed on the absolute vertical velocity, and both velocities can, in particular, add up to a total absolute vertical velocity.

[0014] The specified factor can be derived from the minimum distance of the transverse axis to a point in the other system, whose absolute vertical velocity is determined, and / or from the minimum distance of the longitudinal axis to another point in the other system, whose further absolute vertical velocity is determined; preferably, the factor corresponds to the respective minimum distance. The point can also correspond to the further point. The respective point of the other system, in the sense of a location of the other system, is fictitious and is an integral part of the other system.To determine the product of the factor and the angular velocity measured by the gyroscope, a hardware- or software-implemented amplifier is used. The amplifier receives the angular velocity measured by the gyroscope as its input signal and amplifies it by the respective factor, resulting in the absolute vertical velocity or the further absolute vertical velocity in the direction of the vertical axis. In this way, the absolute or further absolute vertical velocity can be determined in a particularly simple manner using cost-effective hardware- or software-implemented technical means.

[0015] The point of the other system whose absolute vertical velocity is determined, and / or the further point of the other system whose further absolute vertical velocity is determined, can be located at a respective end of the other system that moves in the direction of the vertical axis. Such positioning of the point at the respective, particularly the outermost, end that moves in the direction of the vertical axis during a pitching or rolling motion has the advantage that the distance between the transverse or longitudinal axis and this respective point is maximized. This maximizes the factor by which the respective angular velocity detected by the yaw rate sensor is amplified, i.e., by which the respective angular velocity is multiplied. As a result, the highest possible values, and thus meaningful values, for the absolute and further absolute vertical velocity can be obtained.An amplifier may be provided to determine the absolute vertical velocity and / or a further amplifier to determine the other absolute vertical velocity.

[0016] The damping system is controlled based on positive and negative absolute, or further absolute, vertical velocity values. When the end of the other system, where the respective point is located, moves away from the first system along its vertical axis, the angular rate sensor detects a positive angular velocity, resulting in a positive absolute vertical velocity. Conversely, when the end of the other system, where the respective point is located, moves towards the first system along its vertical axis, the angular rate sensor detects a negative angular velocity, resulting in a negative absolute or further absolute vertical velocity.

[0017] The other system can be pivotally connected to the first system about the transverse or longitudinal axis, preferably at one end, and preferably at its other end connected to the first system via at least one damping system. It is also conceivable that the other system is connected to the first system exclusively via, in particular, four damping systems. If only damping systems are provided, the transverse and longitudinal axes of the other system pass through a center of gravity of the other system and of the device to which the other system may be attached.

[0018] A damping system can be designed as a spring-mass damper system, characterized by the presence of a damper and a spring between a mass and another mass or a fixed point. The spring provides passive damping, while the damper can be designed as a semi-active or active damper.

[0019] In a semi-active damper, the desired damping effect is achieved by changing its damping coefficient. Active and semi-active damping systems have the advantage over passive damping systems that the damper's damping can be adapted to the specific operating state of the system in which the damper is used. Semi-active damping systems offer the advantage over active damping systems, where energy must be supplied to a damper designed as an actuator, of reduced energy consumption and a less complex control system for the damper. The control strategy for actuating the damper can be based, at least partially, on the skyhook approach. However, the damping system is preferably designed as a semi-active damping system controlled by a skyhook-based control strategy.However, it is also possible to implement an active spring-damper system.

[0020] A single yaw rate sensor can be used to detect both pitch and roll motion. Alternatively, one yaw rate sensor could be used for pitch and another for roll. In any case, each yaw rate sensor would detect at least the angular velocity of the other system's pitch about its transverse axis and / or the roll about its longitudinal axis.

[0021] One system can be connected to the motion machine, and the other system can be connected directly or indirectly to a "cockpit" usable by the operator to control the motion machine.

[0022] According to claim 9, the invention also relates to a working machine, in particular an agricultural working machine, preferably a tractor, with a moving machine, a “cockpit” usable by an operator for controlling the moving machine and a device for vibration decoupling between the system associated with the moving machine, in particular connected with the moving machine, and the other system associated with the cockpit, in particular directly or indirectly connected with the cockpit, according to one of the preceding claims.

[0023] The device according to the invention effectively decouples vibrations and shocks emitted by the machine from the machine's cockpit, particularly the driver's cab, so that the cockpit remains largely free of vibrations and shocks during operation. This ensures that the vibrations and shocks do not negatively affect the health of the machine's operator.

[0024] The physical background of the device according to the invention is explained in more detail below:

[0025] The present invention is based on the physical relationship that when a point moves on a circle, the orbital or rotational velocity v of the point on the circle is equal to the product of the angular velocity ω and the radius of the circle r, where the angular velocity ω is equal to the derivative of the rotation angle φ with respect to time t: v=ω∗r=dφdt∗r=φ˙∗r

[0026] Applied to the present invention, the point, in the case of a pitching movement about the transverse axis, is a point of the other system located outside the transverse axis, or in the case of rolling movements about the longitudinal axis, a point located outside the longitudinal axis. If the device according to the invention is inactive or not provided, this point, excited by vibrations of the other system, performs a pitching movement about the transverse axis or a rolling movement about the longitudinal axis in the form of movement along a partial circular path of the circle around the respective transverse or longitudinal axis, in which the center of the circle lies. However, these vibrations have a small amplitude compared to the radius r of the circle, which describes the distance between the center of the circle and the point of the other system on the circle, so that the point moves back and forth along a very short circular path segment, whereby the absolute vertical velocity v is, in this case,z,1 in the direction of the vertical axis z can be approximated by the orbital or rotational velocity v of the point, where L corresponds to the radius r and describes the distance between the center of the circle on the transverse or longitudinal axis and the point of the other system on the circle: vz,1≈v=ω∗L=dφdt∗L=φ˙∗L

[0027] In the following, a device according to the invention and a machine with a corresponding device will be explained in more detail with reference to the drawing. The drawing shows, in a non-scale representation, the Fig. 1a, b in a schematic, perspective principle representation, the device according to the invention is provided with different designations.

[0028] How Fig. As shown in Figures 1a and b, the device according to the invention comprises two systems 2 and 4 in the form of spring-mass oscillators. One system 2 is connected to a drive unit of a working machine, and the other system 4 is connected to a driver's cab of the working machine, which includes a cockpit for controlling the drive unit. The working machine, the drive unit, the driver's cab, and the cockpit are not shown in the figures. The other system 4 is pivotally connected at its end facing the front of the working machine about a transverse axis Q to two pivot points 6 on one system 2. At its end facing the rear of the working machine, it is connected to one system 2 via two damping systems 8, each in the form of a semi-active spring-damper system. Each spring-damper system comprises a spring 10 and a damper, which is not shown in the figures.On the other system 4 or on the driver's cab, a gyroscope (not shown in the figures) is arranged to detect angular velocity values.

[0029] Fig. Figure 1a shows the device according to the invention in an object-related coordinate system (body frame) x, y, z, the origin of which lies in the center of gravity S of the other system and the driver's cabin.

[0030] Particularly during traversing movements of the moving machine, the other system 4 can perform pitching movements about the transverse axis Q. The angular rate sensor detects values ​​of the angular velocity -ω1, ω1 of the other system 4 about the transverse axis Q, at which the end of the other system 4 facing the rear of the working machine moves towards or away from the first system 2, and in particular a vertical movement in the direction of a vertical axis z with a negative -v z1,1 or positive v z1,1absolute vertical velocity ( Fig. 1b) executes, which is derived from the product of the angular velocity values ​​-ω1, ω1 detected by the angular rate sensor and a factor in the form of the minimum distance L1 ( Fig. 1b) of the transverse axis Q to a point P1 ( Fig. 1a) of the other system 4, whose absolute vertical velocity v z1,1 The result is determined by amplifying the angular velocity ω1 values ​​recorded by the angular rate sensor by a factor of 1 using a hardware- or software-implemented amplifier. Fig. 1a is point P1 of the other system 4, whose absolute vertical velocity v z1,1 The measurement is taken at the outermost end of the machine, facing the rear of the machine.

[0031] The absolute vertical velocity v determined in this way z1,1is fed to a control and / or regulation device not shown in the figures, which controls the damping systems 8 to compensate for the vibrations of the other system 4 by means of a control strategy according to the skyhook approach as a function of the absolute vertical velocity v z1,1 The system controls the vibrations and thus decouples the systems from each other. In an embodiment not shown in detail, the respective pivot point 6 is formed from a spring and / or damper system, comparable to the system designated 8 in the figures. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] EP 1 018 445 A2

[0002]

Claims

[1] Device for vibration decoupling between two systems (2, 4) in the form of spring-mass oscillators, one system (2) of which is assigned to a moving machine and the other system (4) to an operator acting on the moving machine, which at least partially performs movements about a transverse axis (Q) during traversing movements of the moving machine and thereby vertical movements in the direction of a vertical axis (z) with an absolute vertical velocity (v z1,1 ) is subject to, which serves as an input variable for control and / or regulating devices that control a damping system (8) of one (2) and / or other (4) system to compensate for the vibrations, characterized by , that the respective pitching movement of the other system (4) is detected by means of at least one gyroscope, the respective measured value (ω1) of which is preferably amplified only by a predefinable factor (L1), the absolute vertical velocity (v z1,1 ) as an input variable. [2] Device according to claim 1, characterized by , that the other system (4) can perform rolling movements about its longitudinal axis during traversing movements of the motion machine and thereby further vertical movements in the direction of the vertical vertical axis (z) with a further absolute vertical velocity (v z2,1 ) is subject to, which serves as a further input variable for the control and / or regulating devices. [3] Device according to claim 1 or 2, characterized by , that the predefinable factor of the minimum distance (L1) of the transverse axis (Q) to a point (P1) of the other system (4), whose absolute vertical velocity (v z1,1 ) is determined, and / or from the minimum distance (L2) of the longitudinal axis to another point (P2) of the other system (4), whose further absolute vertical velocity (v z2,1 ) is determined, can be derived. [4] Device according to one of the preceding claims, characterized by, that the point (P1) of the other system (4), whose absolute vertical velocity (v z1,1 ) is determined, and / or the further point (P2) of the other system (4), whose further absolute vertical velocity (v z2,1 ) is determined, is arranged at a respective end of the other system (4) that is movable in the direction of the vertical vertical axis (z). [5] Device according to one of the preceding claims, characterized by , that the other system (4), in particular with one end, is pivotally connected to the one system (2) at pivot points (6) about the transverse axis (Q) or the longitudinal axis and that the damping system (8) is provided between the other system (4) and the one system (2). [6] Device according to one of the preceding claims, characterized by, that the respective angular velocity (ω1,ω2) of the respective pitching motion of the other system (4) about the transverse (Q) and / or longitudinal axis can be detected by the respective angular rate sensor. [7] Device according to one of the preceding claims, characterized by , that the damping system (8) is designed as a semi-active or active spring-damper system. [8] Device according to one of the preceding claims, characterized by , that one system (2) is connected to the motion machine and the other system (4) is connected directly or indirectly to a cockpit usable by the operator to control the motion machine. [9] Working machine, in particular agricultural working machine, comprising a propulsion machine, a cockpit usable by an operator for controlling the propulsion machine and a device for vibration decoupling between a system (2) associated with the propulsion machine and another system (4) associated with the cockpit, according to one of the preceding claims.

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