KR20100041679A - Damper - Google Patents

Abstract

PURPOSE: A damper is provided to optimally set each damper characteristic value according to various driving conditions by controlling a valid transverse section of a by-pass fluidic channel using a covering disc. CONSTITUTION: A damper includes a damper cylinder in which a piston ram(30) is guided through a piston rod. A flow of a damper fluid is controlled through one or more fluid channels(42,44,52,54) using one or more valve. One or more valve is arranged inside the piston ram. One or more valve controls a damper characteristic value. One or more valves(40,50) includes by-pass fluidic channels(44,54). Covering discs(48,58) control a valid transverse section of the by-pass fluidic channel. The variable damper characteristic value is set in advance.

Description

Damper {DAMPER}

The invention relates to a damper according to the preamble of the independent claim 1.

In conventional passive impingement damper pistons, a spring set, typically consisting of a plurality of leaf springs, is used to form a specific damping force special curve. In a conventional impingement damper piston, the spring rate of the spring set is set once during the design and can no longer be adjusted afterwards. This principle enables the design of economic and robust damper pistons and a very good and practically proven damper characteristic curve.

Also known in the prior art are vehicle dampers comprising an adjustable damper piston, which generally operates according to the principle of a variable open cross section. These dampers can adjust the corresponding impact damper characteristic values via hydraulic proportional valves and adapt to different driving situations. The proportional valve continuously controls the fluid flow in the damper by, for example, a control piston moving by an excitation coil. Proportional valves are flanged to the damper or integrated in the piston ram of the damper. An additional sensor placed on the wheel suspension conveys information about the ingress of the damper. As a sensor, an acceleration sensor or a distance sensor may be used. Associated evaluation and control devices are arranged centrally in the vehicle or around a proportional valve connected by flanged joints. The proportional valve can, for example, indirectly control the main fluid flow, ie the small sub flow is directly regulated by the small control piston, forming a pressure differential with the main valve. The regulated pressure differential regulates the main fluid flow at the main valve. In this way, a relatively large pressure can be adjusted with a relatively low adjustment force. The response time of the damper is limited by the transient response of the proportional valve.

In DE 10 2006 037 172 A1 a damper is known which comprises a damper cylinder in which the piston ram is guided through the piston rod and in which the flow of damper fluid is adjusted to adjust the damper characteristic value. In the damper cylinder, adjusting means or valves are arranged having two independent regulating circuits for the tensioning step and the compressing step, wherein the adjusting means direct the flow of the damper fluid in the first flow direction by the first adjusting means during the compressing step. And during the tensioning step the flow of the damper fluid is regulated in the second flow direction by the second adjusting means. The adjustment value of the first adjustment means for use in the subsequent compression step can be adjusted by the associated first preset means during the tension step given before the compression step, and the second adjustment for use in the subsequent tension step. The adjustment value of the means can be adjusted during the compression step given before the tensioning step, by means of an associated second preset means.

It is an object of the present invention to provide a damper whose damper characteristic value can be adjusted well.

An advantage of the damper according to the features of the independent claim 1 is that at least one valve is arranged in the piston ram and regulates the flow of the damper fluid through the at least one fluid channel to adjust the damper characteristic values. And a rotatably supported covering disc adjusts the effective cross section of the bypass fluid channel to preset the variable damper characteristic value. The covering disc is guided in the housing of the piston ram, for example by thread. Variable damper characteristic values include, for example, the damping factor of the damper that can be used in a vehicle as a collision damper. In this way, the damping factor is changed by changing the flow resistance of the damper fluid through the bypass fluid channel by a change in the cross section of the bypass fluid channel. When the covering disc completely closes the bypass fluid channel, the damper constant is set to maximum hardness. When the bypass fluid channel is fully open, the damper constant is set to the minimum hardness. In the implementation of the damper according to the invention, the assembly cost can be advantageously reduced by a small number of parts. The covering disc is disposed substantially perpendicular to the bypass fluid channel and can be rotated by an electric motor to close or open the bypass fluid channel. By using a covering disc which opens or closes the bypass fluid channel by rotational movement, the cross section of the bypass fluid channel can be changed under a certain load and stick-slip phenomenon is prevented. The damper according to the invention also has a high dynamics.

The preferred improvement of the damper set forth in the independent claim 1 is achieved by the measures and the embodiments set forth in the dependent claims.

Particularly preferably, at least one valve comprises a main fluid channel, the main fluid channel being arranged parallel to the bypass fluid channel, closed by at least one leaf spring, the at least one leaf spring being The elasticity fixedly regulates a predetermined damper characteristic value, and the predetermined damper characteristic value is the maximum hardness value of the damper. The hardness of the damper may vary between the maximum hardness value and the minimum hardness value by means of a damper characteristic value that actively varies through the bypass fluid channel. By the use of two fluid channels, it is possible to simply apply the damper according to the invention to certain passive properties of the damper, for example in case of failure of the electronic device. The passive properties of the damper previously defined by the main fluid channel in connection with the leaf spring can be changed by active adjustment of the cross section of the bypass fluid channel. The covering disc is preferably arranged in the flow path of the damper fluid such that the cross section of the bypass fluid channel varies with the rotational position of the covering disc and the cross section of the main fluid channel does not change regardless of the covering disc rotational position. The variable damper characteristic value can also be structurally influenced by the opening structure of the bypass fluid channel and / or the edge structure of the first through recess of the covering disc.

In an embodiment of the damper according to the invention, the rotatably supported covering disc is driven by an electric motor, preferably an electronically rectified direct current motor, and in the absence of current the covering disc is connected to the cross section of the bypass fluid channel. Cover half. By using an electronically rectified direct current motor, noise minimized operation is possible. The starting position without current of the covering disc can be started even when the ignition lock position is changed and then used as a zero-position to the position regulator. From the zero position, damper characteristics can be adjusted to higher or lower hardness depending on the direction of rotation of the electric motor, the damper characteristics being adjusted to higher hardness by reduction of the cross section of the bypass fluid channel and bypass fluid By extension of the cross section of the channel it can be adjusted to a lower hardness. The electric motor may preferably be integrated into the piston ram, and the ram cover and / or ram with at least one permanent magnet mounted to the covering disc for implementation of the electric motor, the openings of the bypass fluid channel and the main fluid channel being arranged. The base is equipped with a corresponding flat winding and / or hall sensor.

In another embodiment of the damper according to the invention, the piston ram comprises a first valve having a first main fluid channel and a first bypass fluid channel for carrying out the compression step, and a second for carrying out the tensioning step. A second valve having a main fluid channel and a second bypass fluid channel. The first covering covering disc changes the cross section of the first bypass fluid channel to adjust the damper hardness during the compression step, and the second covering disc changes the cross section of the second bypass fluid channel to adjust the damper hardness during the tensioning step. Change. In order to ensure that the compression and tension steps do not affect each other, the first covering disc comprises a first through recess and a second through recess, the recesses being in the flow path of the damper fluid, the first vias. Although the cross section of the pass fluid channel may vary depending on the rotational position of the first covering disc, the cross section of the first main fluid channel, the second main fluid channel and the second bypass fluid channel is independent of the rotational position of the first covering disc. It is arranged not to change. Similarly, the second covering disc comprises a third through recess and a fourth through recess, wherein the recesses, in the flow path of the damper fluid, have a cross section of the second bypass fluid channel rotating in the second covering disc. The position of the first main fluid channel, the second main fluid channel and the first bypass fluid channel can be varied depending on the position, so that the cross-sections of the second covering disc are arranged so as not to change. By this design, the shorter dead time is preferably achieved since the higher or lower hardness properties of the damper are individually adjustable during the tensioning or compression step.

Embodiments of the invention are shown in the drawings and described in more detail in the following description.

According to the present invention, a damper is provided in which adjustment of damper characteristic values is satisfactorily achieved.

Elements or parts which perform the same or similar functions in the drawings are denoted by the same reference numerals.

As shown in FIG. 1, a damper 1 according to the invention, preferably implemented as a collision damper of a vehicle, comprises a damper cylinder 2, in which a piston 10 is movably disposed, The piston includes a piston ram 30 and a piston rod 12. The piston ram 30 divides the damper cylinder 2 into an upper damper chamber 4 and a lower damper chamber 6. By means of the sensor unit, for example, the pressure Poben in the upper damper chamber 4 and the pressure Punten in the lower damper chamber 6 can be detected. As an adjustment value for adjusting the damper characteristic and adjusting the damper characteristic value, a force F acting as the piston 10 of the damper 1 is used. The acting force F can be derived directly from the detected pressures Poben, Punten.

As shown in FIGS. 2 to 5, the piston ram 30 is embodied as a compact unit comprising a ram tube 31, which is implemented as a thin walled steel tube, for example as a housing. The first covering disc 48 and the second covering disc 58 are disposed in the ram tube 31, and the upper portion of the ram tube 31 is press-fitted by the ram cover 32, and the lower portion of the ram tube 31 is press-fitted. 33). As shown in more detail in FIG. 4, the piston ram 30 has a first valve 40 having a first main fluid channel 42 and a first bypass fluid channel 44 for the implementation of the compression step. Include. For carrying out the tensioning step, the piston ram 30 comprises a second valve 50 having a second main fluid channel 52 and a second bypass fluid channel 54. The compression stage and the tension stage are independent actuation stages of the damper 1. During the compression step, the damper fluid flows in the first flow direction, from the lower damper chamber 6 to the upper damper chamber 4, and during the tensioning step, the damper fluid flows in the second flow direction, from the upper damper chamber 4 to the lower damper chamber. Flows into (6).

As shown in FIGS. 2-5, the two valves 40, 50 each comprise one bypass fluid channel 44, 54, the effective cross section of the bypass fluid channels being a variable damper characteristic value. Can be adjusted by rotatably supported covering discs 48, 58 to preset them. Main fluid channels 42, 52 of each valve 40, 50 are arranged parallel to the corresponding bypass fluid channels 44, 54 and are closed by leaf springs 46, 56. As the piston ram 30 moves, two leaf springs affect the flow of damper fluid through the two main fluid channels 43, 53. Thus, during the compression step, the second leaf spring 56 inhibits the flow movement of the damper fluid in the second main fluid channel 52, and the first leaf spring 46 damps in the first main fluid channel 42. Provides resistance to the flow movement of the fluid, which resistance depends on the elasticity of the first leaf spring 46. During the tensioning step, the first leaf spring 46 inhibits the flow movement of the damper fluid in the first main fluid channel 42, and the second leaf spring 56 prevents the damper fluid in the second main fluid channel 52. Provides resistance to the flow motion, which resistance depends on the elasticity of the second leaf spring 56. The elasticity of the leaf springs 46, 56 allows certain damper characteristic values to be fixed in advance. These predetermined damper characteristic values are the maximum hardness values of the damper for the compression stage or the tension stage. The hardness of the damper 1 can be actively changed during the compression or tensioning step through the bypass channels 44, 54, whereby the damper characteristic values can vary between the maximum and minimum hardness values.

In order to set the damper characteristic value, the flow of damper fluid can be regulated by the corresponding covering disks 48, 58 through respective bypass fluid channels 44, 54. The covering disks 48, 58 are arranged perpendicularly to the corresponding bypass fluid channels 44, 54, respectively. The covering disks 48, 58 are rotatably supported and guided in the piston housing 31 by threads. The first covering disk 48 lies under the ram cover 32 in the ram tube 31 and the second covering disk 58 lies above the ram base 33 in the ram tube 31. The first covering disk 48 changes the cross section of the first bypass fluid channel 44 to set the damper hardness during the compression step, and the second covering disk 58 is used to set the damper hardness during the tensioning step. 2 Change the cross section of the bypass fluid channel 54. In the ram cover 32, a first main channel opening 3. 1 for the first main fluid channel 42, a first bypass opening 332. for the first bypass fluid channel 44, and a second main fluid channel 52. Third main channel opening (32.3), and third bypass opening (32.4) for second bypass fluid channel (54). In the ram base 33 a second main channel opening 33.1 for the first main fluid channel 42, a second bypass opening 33.2 for the first bypass fluid channel 44, a second main fluid channel 52 A third main channel opening (33.3) for the second and fourth bypass opening (33.4) for the second bypass fluid channel 54 is provided.

As shown in FIGS. 2-5, the first covering disk 48 comprises a first through recess 48.1 and a second through recess 48.2, which recesses in the flow path of the damper fluid. The cross section of the first bypass fluid channel 42 varies with the rotational position of the first covering disk 48, but the first main fluid channel 42, the second main fluid channel 52, and the second bypass fluid The cross sections of the channel 54 are arranged unchanged regardless of the rotational position of the first covering disk 48. The second cover disk 58 includes a third through recess 58.1 and a fourth through recess 56.2, which recesses in the flow path of the damper fluid, the second bypass fluid channel 52. The cross section changes depending on the rotational position of the second covering disc 58, but the cross sections of the first main fluid channel 42, the second main fluid channel 52 and the first bypass fluid channel 44 are the second covering disc. It is arrange | positioned so that it does not change irrespective of the rotation position of 58. FIG. In the illustrated embodiment, the two bypass fluid channels 44, 54 are fully open, so that a damping factor of minimum hardness is established during the compression step and during the tension step. In the compression step, the first covering disc 48 is rotated counterclockwise to set a higher hardness damping factor, and the shielding area 48.3 of the first covering disc 48 has a first bypass fluid channel. Moved above 44 to reduce the effective cross section of the first bypass fluid channel 44. In the tensioning step, in order to set the damping factor of higher hardness, the second covering disc 58 rotates counterclockwise, and the shielding area 58.3 of the second covering disc 58 becomes the second bypass fluid. Moved over channel 54 to reduce the effective cross section of second bypass fluid channel 54. In addition, the variable damper characteristic value may include an opening structure of the bypass fluid channels 44 and 54 and / or an edge of the first or third through recess 48.1 and 58.1 of the two covering disks 48 and 58. It may be structurally affected by the structure.

The covering disks 48, 58 are each moved by an electric motor, not shown, which is preferably implemented as an electronically rectified direct current motor. The electric motor may for example be integrated into the piston ram 30. At least one permanent magnet may be mounted to the covering disks 48, 58 for the implementation of the electric motor, and the ram cover 32 or the ram base may be equipped with a corresponding planar winding and / or hall sensor. In the absence of current, the two covering disks 48, 58 cover half of the cross section of the corresponding bypass fluid channels 44, 54, respectively. This current-free starting position of the covering discs 48, 58 can be started even in the event of a change in the ignition lock position and then used as a zero-position in the position adjuster. From the zero position, the damper characteristic can be adjusted to a higher or lower hardness depending on the direction of rotation of the corresponding electric motor, the damper characteristic being further reduced by the reduction of the cross section of the corresponding bypass fluid channels 44, 54. It can be adjusted to a higher hardness and to a lower hardness by expanding the cross sections of the corresponding bypass fluid channels 44, 54. If each of the covering disks 48, 58 completely closes the bypass fluid channels 44, 54, the damper constant can be set to the maximum hardness. Once the bypass fluid channels 44, 54 are fully open, the damper constant can be set to the minimum hardness. Thus, the two leaf springs 46, 56 form one application parameter for the adjustment of the passive damper characteristic, but the expansion of the damper characteristic can only be adjusted by the active covering discs 48, 58.

In the embodiment of the damper according to the invention, preferably, the respective damper characteristic values can always be optimally set for various driving situations. Unlike conventional hydraulic proportional valves, the valve according to the invention is capable of directly regulating damper fluid flow without delay or transient state, and is preferably adjustable with less control force even during loading. By way of a very compact embodiment, the damper according to the invention is also suitable for damping of the vehicle cabin of a commercial vehicle, damping of vehicle seats, trailers and the like. The damper according to the invention is also suitable for applications in addition to vehicle technology, for example in applications where an adjustable damper with a compact structure is required.

1 is a perspective view of a damper according to the present invention,

FIG. 2 is a first perspective view of the piston ram of the damper according to FIG. 1,

3 is a second perspective view of the piston ram of the damper according to FIG. 1,

4 is a plan view of the piston ram according to FIGS. 2 and 3,

5 is an exploded view of the piston ram according to FIGS. 2 to 4.

Claims (10)

The piston ram 30 comprises a damper cylinder 2, which is guided through the piston rod 12, wherein the flow of damper fluid is at least one fluid channel 42, 44, 52, 54 to adjust the damper characteristic value. In the damper adjustable by at least one valve 40, 50 disposed in the piston ram 30, The at least one valve 40, 50 comprises a bypass fluid channel 44, 54, and the rotatably supported covering discs 48, 58 allow the bypass fluid to preset variable damper characteristic values. Damper, characterized in that for adjusting the effective cross section of the channel (44, 54). The method of claim 1, The at least one valve 40, 50 comprises a main fluid channel 42, 52, the main fluid channel being arranged parallel to the bypass fluid channel 44, 54 and having at least one leaf spring ( 46, 56 closed, the elasticity of the at least one leaf spring 46, 56 is fixed to adjust the predetermined damper characteristic values, the predetermined damper characteristic values are the damper (1) And the hardness of the damper 1 can vary between the maximum hardness value and the minimum hardness value by damper characteristic values that are actively variable through the bypass fluid channels 44, 54. Damper. The method according to claim 1 or 2, The covering discs 48, 58 may be in the flow path of the damper fluid so that the cross-section of the bypass fluid channels 44, 54 may change depending on the rotational position of the covering discs 48, 58, and the main fluid channel. And the cross section of the (42, 52) is arranged such that it cannot be changed irrespective of the rotational position of the covering disc (48, 58). The method according to any one of claims 1 to 3, The variable damper characteristic value is structurally affected by the opening structure of the bypass fluid channels 44, 54 and / or the edge structure of the first through recesses 48. 1, 58.1 of the covering discs 48, 58. Damper characterized in that. The method according to any one of claims 1 to 4, The rotatably supported covering discs 48, 58 are driven by an electric motor, preferably an electronically rectified direct current motor, which covers the bypass fluid channels in the absence of current. A damper, characterized by covering half of the cross section of (44, 54). The method of claim 5, The electric motor is integrated in the piston ram 30, for the implementation of the electric motor, at least one permanent magnet is mounted on the covering disks 48, 58, and the bypass fluid channels 44, 54. ) And the ram cover 32 and / or the ram base 33 of the piston ram 30, in which the openings 3. 1 to 32.4, 33.1 to 33.4 of the main fluid channels 42, 52 are disposed, corresponding flat windings. And / or hall sensors are mounted. 7. The method according to any one of claims 1 to 6, The piston ram 30 comprises a first valve 40 having a first main fluid channel 42 and a first bypass fluid channel 44 for the carrying out of the compression step, for carrying out the tensioning step. And a second valve (50) having a second main fluid channel (52) and a second bypass fluid channel (54). The method of claim 7, wherein The first covering disk 48 changes the cross section of the first bypass fluid channel 44 to adjust the damper characteristic value during the compression step, and the second covering disk 58 adjusts the damper characteristic value during the tensioning step. Damper, characterized in that for changing the cross section of the second bypass fluid channel (54). The method of claim 8, The first covering disk 48 comprises a first through recess 48.1 and a second through recess 48.2, the recesses in the flow path of a damper fluid, the first bypass fluid channel 44 Cross-section of the first main fluid channel 42, the second main fluid channel 52 and the second bypass fluid channel 54 can be varied according to the rotational position of the first covering disc 48. The cross section is characterized in that the damper is arranged invariably regardless of the rotational position of the first covering disk (48). The method according to claim 8 or 9, The second covering disk 58 includes a third through recess 58.1 and a fourth through recess 58.2, the recesses being in the flow path of the damper fluid, the second bypass fluid channel 54 Cross section of the first main fluid channel 42, the second main fluid channel 52 and the first bypass fluid channel 44 can be varied according to the rotational position of the second covering disc 58. Dampers, characterized in that they are arranged invariably regardless of the rotational position of the second covering disc (58).

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