WO2015086687A1

WO2015086687A1 - Linear bearing with vibration damping

Info

Publication number: WO2015086687A1
Application number: PCT/EP2014/077241
Authority: WO
Inventors: Johannes Goetz; Markus Behn; Thomas Deigner; Jochen Dusel; Fred Menig; Dieter Schaefer; Sascha Vorbeck; Thomas Will
Original assignee: Aktiebolaget Skf; SKF ECONOMOS Deutschland GmbH
Priority date: 2013-12-10
Filing date: 2014-12-10
Publication date: 2015-06-18
Also published as: DE102013225328A1

Abstract

The invention relates to a linear bearing (2) with a first bearing body (4) and a second bearing body (6). At least one active vibration damping unit (16), in particular a piezoelement, is arranged on and/or in the first bearing body (4) and/or on and/or in the second bearing body (6). The invention also relates to a linear bearing arrangement comprising said type of linear bearing (2) and to a method for damping vibrations in said type of linear bearing (2).

Description

Linear bearing with vibration damping

The present application relates to a linear bearing with a first bearing body and a second bearing body, and a method for damping vibrations in a linear bearing.

In linear bearings, vibrations or vibrations are known to be often introduced during operation. These vibrations have been taken into account so far that the components of the linear bearing are designed such that they are not damaged by the vibrations or vibration as possible. However, for this purpose, the materials and components that can be used in the linear bearing must meet high requirements. Nevertheless, the vibrations and vibrations lead to increased wear and again to a direct damage to the affected linear bearing.

Object of the present invention is therefore to provide a linear bearing, which is as resistant to vibration as possible.

This object is achieved by a linear bearing according to claim 1, a linear bearing assembly according to claim 6, and a method according to claim 10.

According to the invention, a linear bearing is provided with a first bearing body and a second bearing body, which are designed to be movable relative to one another and are designed to be connectable to elements to be supported. In this case, the invention is based on the idea, on or in the first bearing body and / or on or in the second bearing body at least one active vibration damper unit, in particular a piezoelectric element to arrange.

In this case, the active vibration damper unit according to the invention makes it possible actively to act on the linear bearing with a counter-vibration, with which a registered in the linear bearing vibration can be compensated. For this purpose, the registered oscillation is preferably detected, a compensating countervibration calculated and the active vibration damping element driven in such a way that it executes the corresponding countervibration. Although passive vibration damping elements are known from the prior art, they can dampen the vibrations and vibrations only to a limited extent. In addition, the installation of linear bearings itself is difficult, so that the linear bearing itself undergoes no vibration damping, but only through the linear bearing against each other movable elements.

The active vibration damper unit according to the invention on the linear bearing itself, however, not only reduces a vibration input to the connected via the linear bearing elements, but at the same time allows vibration damping of the bearing itself, which leads to a particularly great smoothness. At the same time damage to the linear bearing due to vibrations are reliably prevented.

According to a further advantageous embodiment, the at least one active vibration damper unit is formed integrally with the first bearing body and / or the second bearing body. Since vibrations are transmitted, in particular, from the first bearing body to the second bearing body or vice versa, an active introduction of countervibrations on the first bearing body or second bearing body can directly reduce or compensate the vibrations arising on the linear bearing.

According to a further advantageous embodiment, the active vibration damper unit has at least one actuator for generating a vibration, wherein the actuator is preferably a piezoactuator. The actuator arranged in the vibration damper unit actively ensures the generation of the countervibration of the linear bearing component with the vibration damper unit. This means, for example, that, upon detection of a vibration in a first bearing body with an active vibration damper unit, the actuator of the vibration damper unit to the vibration generates appropriate counter-vibration in the first bearing body, so that compensate for the two oscillations. Preferably, piezoactuators are particularly suitable for this, since corresponding countervibrations can be formed quickly and precisely with them.

According to a further advantageous embodiment, the entire active vibration damper unit is designed as a piezoelectric element, which is preferably arranged in vibration-induced deformation of force-transmitting connection on / in the first bearing body and / or on / in the second bearing body. Piezoelectric elements have the advantage that they can be arranged directly in the components, for example, the first or second bearing body, and this can act on a counter-vibration. Furthermore, they are easy to control and offer a wide range of executable vibrations. In addition, the oscillations can be actively "switched on" or "switched off", so that no undesirable oscillation entry takes place via a ringing of the vibration damper unit.

According to a further advantageous embodiment, the vibration damper unit further comprises a sensor which is designed to detect a vibration, wherein preferably the sensor is designed as a voltage detector, which detects a voltage arising during deformation of the piezoelectric element.

In order to specify a counter vibration, it is advantageous to first analyze the registered vibration. This is advantageously carried out by means of the sensor element. In this case, for example, the vibration induced deformation of the piezoelectric element can be measured via the voltage generated by the piezoelectric element, which in turn is used as the basis for the calculation of the countervibration. Alternatively, another element for vibration detection can be used.

According to another aspect of the present invention, there is provided a linear bearing assembly having a linear bearing as described above and an active vibration damper unit, wherein the active vibration damper unit is operatively connected to a control unit. In this case, the control unit allows both an evaluation of the measured quantities of the sensor element and thus of the detected oscillation, as also setting the complementary counter-vibration thereto, as well as driving the active vibration damper element for generating the predetermined counter-vibration.

In this case, it is furthermore advantageous if the control unit controls the actuator of the vibration unit such that a vibration in the active vibration damping unit can be induced via the control unit. In this case, the control unit can in particular have a voltage source which applies a voltage to the piezoelectric element according to the invention, so that this is deformed and thereby counteracts the oscillation.

According to a further advantageous embodiment, the voltage source can also be designed as a voltage s memory, for example as a capacitor, which is not only designed to generate a voltage but also to store a voltage. As a result, the active vibration damper unit, in particular the piezoelectric element, can alternatively be used to transform an oscillation entered into the linear bearing into current or voltage, which is then stored in the capacitor. It can be provided in particular that, for example, only a counter-vibration is generated when an amplitude or frequency of the registered oscillation is within a certain critical range. Thus, for example, the linear bearing may be formed as a current-producing element during non-critical vibration states, while at critical vibration states, for example in the region of resonant vibrations, an active vibration damping is provided via the generation of a countervibration.

In addition, the energy generated can be made available elsewhere, for example, to operate the various sensors.

Another aspect of the present invention relates to a method for damping a vibration in a linear bearing or a linear bearing arrangement, as described above, wherein the method in a first step, a vibration of the linear bearing, preferably detected by means of the sensor element, then a counter-vibration, preferably by means of Control is determined, and by driving, for example, an actuator of the active vibration unit, a counter-vibration is generated, which is registered as a counter-vibration in the linear bearing. It is particularly advantageous if the linear bearing is equipped with a designed as a piezoelectric element vibration damper unit. In this case, an active vibration damping according to the invention is generated in that a deformation force caused by a vibration of the first bearing body and / or the second bearing body acts on the piezoelectric element. The voltage generated by the deformation force is detected, preferably by means of the voltage detector detected, passed to the control, which determines therefrom the registered vibration and determines a counter-vibration. Subsequently, a counter-deformation of the piezoelectric element is in turn generated by applying to the piezoelectric element belonging to the counter-vibration, so that this counter-deformation force of the piezoelectric element is transmitted to the first bearing body and / or the second bearing body, and thus counteracts the counter-vibration.

It is particularly advantageous if the generation of the countervibration is performed only when vibrations are detected, their frequency and / or

Amplitude over a certain threshold and / or fall below and / or are within a certain range. As already mentioned above, thereby resonant vibrations can be prevented, while registered in the linear bearing uncritical vibrations for generating current due to the voltage change on the piezoelectric element can be used.

Further advantages and advantageous embodiments are defined in the claims, the description and the figures.

In the following, the principle of the invention will be described in more detail with reference to embodiments shown in the figures. The embodiments are purely exemplary in nature and are not intended to determine the scope of the application. This is defined solely by the appended claims.

Show it:

1 shows a schematic diagram of a first embodiment of the linear bearing according to the invention;

2 shows a schematic basic illustration of a second embodiment of the linear bearing according to the invention; and 3 is a schematic diagram of a third embodiment of the linear bearing according to the invention.

Hereinafter, the same or functionally equivalent elements are identified by the same reference numerals.

Fig. 1 shows a schematic representation of a linear bearing assembly 1 with a linear bearing 2, which has a first bearing body 4 and a second bearing body 6, which are mutually linear, ie in the illustrated embodiment, perpendicular to the plane movable. It can be arranged between the first and second bearing body 4, 6 rolling elements 8, which provide for a relative mobility of the bearing body 4, 6 to each other. According to the first embodiment shown in Fig. 1, a fiction, contemporary active vibration damper unit 16 is further arranged on the first bearing body 4 and the second bearing body 6. According to the principle, an active vibration damper unit 16, such as an active vibration, is constructed more stably with a mass element 18, a spring element 20, an actuator 22 and a damper 24. Preferably, however, the active vibration damper unit 16 is designed as a piezo element which, due to its inherent properties, performs the functions of FIG Mass element, spring element, damper and actuator united in it. As is known, a piezoelectric element can be deformed upon application of a voltage, or generate a voltage upon deformation. This can be used according to the invention to generate a pulsating deformation of the piezoelectric element by applying a specific voltage sequence or specific voltage pulses, which in turn leads to the generation or the entry of a vibration in the component of the linear bearing, or in which the piezoelectric element is arranged.

Furthermore, FIG. 1 shows that the active vibration damper unit 16 furthermore has a sensor 26 which is designed to detect a vibration registered on the vibration damper unit 16. When using a piezoelectric element, the sensor unit 26 may be designed in particular as a voltage detector. Since a piezoelectric element experiences a deformation force due to vibrations, which in turn leads to a voltage change on the piezoelectric element, this voltage can be detected. Furthermore, the linear bearing arrangement 1 according to the invention has a control 28, which is in operative connection with the sensor unit 26 and receives information about a registered oscillation from the sensor unit 26. The information about the vibration can be processed, for example, in the control unit 28, which in turn calculates a counter-vibration which is suitable for compensating the registered vibration. In order to generate this countervibration, the control unit 28 in turn controls the actuator 22 of the active vibration damper unit 16 or the piezoelement in such a way that it induces a counteroscillation in the vibration damper unit 16. This can be done analogously, for example, by driving the mass 18, which in turn transmits the oscillation via the spring element 20 to the first bearing body 4 and / or the second bearing body 6. In the preferred embodiment of a piezoelectric element, however, the countervibration can be generated by applying a corresponding voltage sequence to the piezoelectric element, which in turn causes a corresponding deformation of the piezoelectric element, so that generates a vibration-compensating counter vibration on the first and / or second bearing body 4, 6 becomes.

In this case, provision may in particular be made for the countervibration to be generated only when the vibration registered in the linear bearing 2 moves in a resonance range or critical range. If the active vibration damper unit 16 is designed as a piezoelectric element, the deformation of the piezoelectric element caused by the vibration can also generate a voltage which is output to a voltage source (not shown) connected to the control unit. As a result, the linear bearing system 1 according to the invention can be used, on the one hand, to generate electrical energy by means of the uncritical vibrations registered during operation. However, if the registered oscillation is in a critical range, the piezoelectric element, instead of generating electrical energy, can be used to actively damp the vibrations, so that damage to the linear bearing and the surrounding components is actively counteracted.

Fig. 2 shows another preferred embodiment of a linear bearing assembly 1 with a linear bearing 2 and an active vibration damper unit 16, wherein the vibration damper unit 16 is arranged in the embodiment shown on the first bearing body 4 of the linear bearing 2. Between the first bearing body 4 and the second bearing body 6, an element 10 to be supported is sketched. Instead, as shown in FIGS. 1 and 2, that the linear movement takes place along rail-shaped bearing bodies 4, 6, as shown in FIG. 3, a round element 10 to be supported can also be encompassed by the linear bearing. Also in this case, the arrangement of the fiction, contemporary active vibration damper unit 16 is preferred, this being arranged in particular in the inner second bearing body.

Of course, the vibration damper unit 16 can be arranged multiple along the circumference of the first and / or second bearing body 4, 6, so that a particularly good vibration damping is achieved. This is analogous to a configuration in another component of the linear bearing 2. It may be sufficient to arrange an active vibration damping only in the axial direction of the linear bearing 2 perpendicular aligned X and Y direction of the bearing body 4, 6. Upon oscillation of the vibration damper element 16 in the X direction and in the Y direction, all vibrations registered on the bearing rings 4, 6 can be represented and compensated in the X or Y direction. In addition, a vibration damper unit 16 may also be provided in the Z direction, so that not only vibrations in the plane of the drawing but also perpendicular to the plane of the drawing can be compensated.

Of course, the provision of the active vibration damper unit 16 is possible not only on the illustrated linear bearings, but also on bearing combinations or other designed bearings.

Advantageously, the inventive active vibration damper element 16 allows a particularly good vibration damping and at the same time also a vibration damping only in certain applications.

LIST OF REFERENCE NUMBERS

1 linear bearing arrangement

2 linear bearings

4 First bearing body

6 Second bearing body

8 rolling elements

10 component to be stored

16 active vibration damper unit

18 mass element

20 spring element

22 actuator

24 dampers

26 sensor element

28 control

Claims

P atentansprü che linear bearing with vibration damping

1. linear bearing (2) having a first bearing body (4) and a second bearing body (6), which are designed to be movable against each other and are adapted to be connected with elements to be stored (10), characterized in that on and / or in the first and / or second bearing body (4; 6) at least one active vibration damper unit (16), in particular a piezoelectric element, is arranged.

2. Linear bearing (2) according to claim 1, wherein the at least one active vibration damper unit (16) integral with the first bearing body (4) and / or the second bearing body (6) is formed.

3. Linear bearing (2) according to claim 1 or 2, wherein the active vibration damper unit (16) comprises an actuator (22) for generating a vibration, wherein the actuator (22) is preferably a piezoelectric actuator.

4. Linear bearing (2) according to any one of the preceding claims, wherein the vibration damper unit (16) is designed as a piezoelectric element, preferably in vibration sbedingter deformation of force transmitting connection to and / or in the first and / or second bearing body (4, 6) is arranged ,

5. Linear bearing (2) according to any one of the preceding claims, wherein the vibration damper unit (16) further comprises a sensor (26) which detects a vibration, wherein preferably the sensor (26) is designed as a voltage detector, the one in deformation of the Piezo element detected voltage detected.

6. Linear bearing arrangement (1) with a linear bearing (2) according to one of the preceding claims and a standing with the active vibration damper unit (16) in operative connection control unit (28).

7. Linear bearing arrangement (1) according to claim 6, wherein the control unit (28) the actuator (22) of the vibration damper unit (16) controls such that via the control unit (28) a vibration in the vibration damper unit (16) is inducible.

8. Linear bearing arrangement (1) according to claim 6 or 7, wherein the control unit (28) further comprises a voltage source, in particular a capacitor, wherein the voltage source is adapted to generate a voltage and / or to store a voltage.

9. Linear bearing arrangement (1) according to claim 8, wherein the active vibration damper element (16) is a piezoelectric element and an induced on the piezoelectric element via a vibration of the first bearing body (4) and / or the second bearing body (6) voltage in the voltage source can be stored ,

10. A method for damping a vibration in a linear bearing (2) according to one of the preceding claims, comprising the following steps:

- Detecting a vibration of the linear bearing (2), preferably by means of the sensor element (26);

- determining a countervibration, preferably by means of the control element (28); and

- Driving the active vibration damper unit (16) for generating the counter-vibration, preferably by means of the control element (28).

11. The method according to claim 10, wherein the linear bearing (2) is equipped with a piezoelectric element designed as a vibration damper unit (16), comprising the following steps:

- Entering a by a vibration of the first bearing body (4) and / or the second bearing body (6) caused deformation force on the piezoelectric element; - Detecting the deformation of the piezoelectric element generated by the deformation force, preferably by means of a voltage detector (26);

- Determining a voltage to be applied to the piezoelectric element for generating a counter-deformation, preferably by means of the control element (28);

- Applying the determined voltage to the piezoelectric element for generating the counter-deformation of the piezoelectric element and a counter-deformation force, preferably by means of the control element (28); and

- Entering the counter-deformation generated by the counter-deformation of the piezoelectric element skraft on the first bearing body (4) and / or the second bearing body (6) of the linear bearing (2).

12. The method of claim 11, wherein a damping of the vibration over

rhythmic generation of counter-deformation forces on the first bearing body (4) and / or the second bearing body (6) of the linear bearing (2).

13. The method according to any one of the preceding claims 10 to 12, wherein the step of generating a counter-vibration is carried out at oscillations whose frequency and / or amplitude exceed a certain threshold and / or fall below and / or are within a certain range.