CN113719543B - Dry friction variable damping vibration damper - Google Patents
Dry friction variable damping vibration damper Download PDFInfo
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- CN113719543B CN113719543B CN202111084798.9A CN202111084798A CN113719543B CN 113719543 B CN113719543 B CN 113719543B CN 202111084798 A CN202111084798 A CN 202111084798A CN 113719543 B CN113719543 B CN 113719543B
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- damping
- damping ring
- movable
- flange seat
- fixed
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16C—SHAFTS; FLEXIBLE SHAFTS; ELEMENTS OR CRANKSHAFT MECHANISMS; ROTARY BODIES OTHER THAN GEARING ELEMENTS; BEARINGS
- F16C35/00—Rigid support of bearing units; Housings, e.g. caps, covers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
- F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
- F16F15/02—Suppression of vibrations of non-rotating, e.g. reciprocating systems; Suppression of vibrations of rotating systems by use of members not moving with the rotating systems
Abstract
The invention discloses a dry friction variable damping vibration damper, comprising: the clamping cover and the base are internally provided with a fixed damping ring, a movable damping ring, a flange seat and a reset spring, the fixed damping ring is fixedly arranged on two sides of the inner walls of the clamping cover and the base, the movable damping ring is arranged close to the fixed damping ring, the flange seat is arranged between the movable damping rings, the reset spring is arranged in a clamping position between the movable damping ring and the flange seat, two ends of the reset spring are respectively and fixedly connected with the movable damping ring and the flange seat, the initial state of the reset spring is a pre-stretching state, and a piezoelectric actuator is arranged in the flange seat; a pair of bearings and shaft sleeves are arranged between the movable damping ring and the rotating shaft and between the flange seat and the rotating shaft. The dry friction variable damping device can realize active control of dry friction damping, and can be adapted to rotating machinery adopting rigid support and rotating machinery adopting elastic support.
Description
Technical Field
The invention relates to the technical field of damping vibration attenuation devices, in particular to a dry friction variable damping vibration attenuation device.
Background
Rotary machines such as helicopter tail shafts induce severe self-excited vibration near and above critical rotational speeds, and there is a pressing need for vibration damping and isolation devices. At present, rotary machines such as helicopter tail shafts mainly adopt dry friction dampers, squeeze film dampers and magneto-rheological dampers. The squeeze film damper can be subjected to high nonlinear influence of oil film rigidity under the condition that the unbalance amount of a rotor system is too large to cause dynamic problems such as locking, bistable state and the like, and the installation of an oil way by the tail space of a machine body is limited. The temperature rise phenomenon caused by long-time work of the magneto-rheological damper can affect the mechanical property and the stability of the magneto-rheological damper, and the control effect on transverse bending vibration is not ideal. Relatively speaking, because the structure is simpler, the dry friction damper is still a hot point of the current damping vibration attenuation device research, and the dry friction damping vibration attenuation device which can be actively controlled by using intelligent materials such as piezoelectric ceramics and the like is widely concerned by domestic and foreign scholars. However, the existing active-control dry friction damping vibration attenuation devices all adopt a piezoelectric actuator one-way output design, the adjustable friction damping is small, and the vibration attenuation effect is limited.
In recent years, damping techniques based on piezoceramic materials have been developed. The patent "an intelligent structure bullet props up dry friction damper" (ZL 201510873150.8) has designed squirrel-cage elastic support structure, controls the attenuator according to its strain fluctuation condition, consequently leads to overall structure complicacy, bulky, and utilizes the degree of the indirect detection vibration of meeting an emergency can not guarantee the accuracy of control. Secondly, its component that is used for the support all adopts integrative annular design like the bearing, is unfavorable for later maintenance and overhaul. Finally, because the dynamic friction plate is fixedly connected with the elastic support of the inner squirrel cage, the dynamic friction plate rotates along with the shaft, so that high-speed rotation motion exists between the dynamic friction plate and the static friction plate, and the load torque of the rotor system is increased. The patent "piezoelectric type self-balancing elastic support dry friction damper of a rotating machinery rotor supporting structure" (application number 201911015747.3) adopts and moves, the static friction piece is placed in the middle, the design overall arrangement that the piezoelectric actuator of both sides is exerted power to the centre to lead to hugging closely the force sensor of static friction piece and need set up in the middle of the damper, be unfavorable for the wiring and take place the winding with other movable parts easily. Secondly, due to the design of the axial split belleville spring and the bracket thereof, the whole structure is not compact enough and is complex. Finally, since each flap of the disc-shaped split spring needs to be provided with a piezoelectric actuator, the manufacturing cost is high, and the problem of synchronous control of a plurality of piezoelectric actuators needs to be considered, so that the requirement on control is relatively high. In addition, the two patents adopt the design of unidirectional output of the piezoelectric actuator, the adjustable friction damping is small, and the vibration damping effect is limited.
Therefore, the invention provides a dry friction variable damping vibration attenuation device with compact structure and simple control, which meets the requirement of helicopter tail shafts or other rotating machinery on large damping vibration attenuation and becomes a problem to be solved by the technical personnel in the field.
Disclosure of Invention
The invention aims to solve the technical problem of providing a dry friction variable damping vibration attenuation device which is compact in structure and simple to control and can meet the requirement of a helicopter tail shaft or other rotating machinery on large damping vibration attenuation. In order to solve the above problems, the technical solution provided by the present invention is as follows:
the invention relates to a dry friction variable damping vibration damper, comprising: the clamping cover and the base are hollow and are matched with each other, a fixed damping ring, a movable damping ring, a flange seat and a reset spring are arranged in the clamping cover and the base, the fixed damping ring is fixedly arranged on two sides of the inner walls of the clamping cover and the base, the movable damping ring is arranged close to the fixed damping ring, the flange seat is arranged between the movable damping rings, the reset spring is arranged in a clamping position between the movable damping ring and the flange seat, two ends of the reset spring are respectively and fixedly connected with the movable damping ring and the flange seat, the initial state of the reset spring is a pre-stretching state, and a piezoelectric actuator is arranged in the flange seat; and a pair of bearings and shaft sleeves are arranged among the movable damping ring, the flange seat and the rotating shaft.
Furthermore, a pair of fixed damping rings and a pair of movable damping rings are symmetrically arranged in the clamping cover and the base, and the fixed damping rings and the movable damping rings generate friction damping through end face contact.
Furthermore, the fixed damping ring is fixedly embedded in the clamping cover and two sides of the inner wall of the base through clamping grooves; or the fixed damping ring is fixed on the clamping cover and two sides of the inner wall of the base through pins or rivets.
Furthermore, the flange seat circumference evenly is provided with a plurality of through-holes that are used for along the axial installation piezoelectric actuator, the quantity of through-hole is the even number.
Further, the piezoelectric actuator is used for generating acting force to two ends and pushing the movable damping ring to press the fixed damping ring; the reset spring is used for pulling the movable damping ring away from the fixed damping ring after the piezoelectric actuator is unloaded.
The dry friction variable damping vibration attenuation device provided by the invention has the beneficial effects that:
1. the dry friction variable damping device can realize active control of dry friction damping, and can be adapted to rotating machinery adopting rigid support and rotating machinery adopting elastic support.
2. The dry friction variable damping device realizes the parallel connection of the dry friction damping at two sides through the middle of the piezoelectric actuator, can further amplify the control effect of voltage on the damping, and can provide larger dry friction damping.
3. The dry friction variable damping device enables the movable damping ring not to rotate along with the shaft and only transmits the vibration of the shaft through the bearing arranged between the movable damping ring and the flange seat and between the movable damping ring and the shaft, so that the load torque of a rotor system cannot be increased in the vibration reduction process.
4. The dry friction variable damping device has the characteristics of compact size, symmetrical structure and simplicity in control, and the clamping cover and the base for supporting and positioning are designed in an up-and-down separated mode, so that the dry friction variable damping device is easy to install, adjust and maintain in a later period.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic overall appearance of the dry friction variable damping vibration damping device of the present invention;
FIG. 2 is a schematic view of the structure of the locking cover of the dry friction variable damping vibration damping device of the present invention;
FIG. 3 is a schematic view of the structure of the base of the dry friction variable damping vibration damping device of the present invention;
FIG. 4 is a schematic view of a flange seat structure of the dry friction variable damping vibration damping device of the present invention;
FIG. 5 is a schematic diagram showing the internal structure of the dry friction variable damping vibration damper of the present invention in longitudinal section, wherein only the upper half, i.e., the structure inside the locking cover, is shown.
Detailed Description
In order to make the technical solutions in the embodiments of the present invention better understood and make the above objects, features and advantages of the present invention more comprehensible, specific embodiments thereof will be described in detail below with reference to the accompanying drawings.
It should be noted that the description of the embodiments is provided to help understanding of the present invention, but the present invention is not limited thereto. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
Referring to fig. 1 to 5, a dry friction variable damping vibration damping device of the present embodiment includes: the clamping cover comprises a clamping cover 1 and a base 2 which are hollow and mutually adaptive, wherein a fixed damping ring 3, a movable damping ring 4, a flange seat 5 and a reset spring 6 are arranged inside the clamping cover 1 and the base 2, the fixed damping ring 3 is fixedly arranged on two sides of the inner walls of the clamping cover 1 and the base 2, the movable damping ring 4 is arranged close to the fixed damping ring 3, the flange seat 5 is arranged between the movable damping rings 4, the reset spring 6 is arranged in a clamping position between the movable damping ring 4 and the flange seat 5, two ends of the reset spring 6 are respectively and fixedly connected with the movable damping ring 4 and the flange seat 5, the initial state of the reset spring 6 is a pre-stretching state, and a piezoelectric actuator 7 is arranged in the flange seat 5; a pair of bearings 9 and a shaft sleeve 10 are provided between the movable damping ring 4 and the flange seat 5 and the rotating shaft 8. The outer contour of the clamping cover 1 is in an omega shape and is connected with the base 2 up and down through bolts, the clamping cover 1 is connected and matched with the base 2 to form an annular hollow structure, and other components of the dry friction variable damping vibration attenuation device are arranged in the hollow structure between the clamping cover 1 and the base 2. The movable damping ring 4 is connected with the flange seat 5 through a reset spring 6, the end face of the inner side of the movable damping ring 4 is tightly pressed with the end face of the outer side of the flange seat 5 under the action of the pre-stretched reset spring, and the inner ring of the movable damping ring 4 is in contact with the outer ring of the bearing 9 to realize radial positioning. The installation is striden to flange seat 5, presss from both sides in the middle of two pairs of fixed damping ring 3 and movable damping ring 4, and the outer circumference design of flange seat 5 has the flange to be used for the installation to realize radial positioning with the reset spring 6 that movable damping ring 4 is connected, inner circle through with the contact of bearing 9 outer lane, and radial design has the through-hole for installation hollow locating pin and draw forth the control line.
Preferably, a pair of fixed damping rings 3 and a pair of movable damping rings 4 are symmetrically arranged inside the locking cover 1 and the base 2, and the fixed damping rings 3 and the movable damping rings 4 generate friction damping through end face contact. Thus, the side surfaces of the fixed damping ring 3 and the movable damping ring 4 which are in contact form a working surface which generates frictional damping when pressed against each other, the two constituting a dry friction assembly.
Preferably, the fixed damping ring 3 is fixedly embedded in the clamping cover 1 and two sides of the inner wall of the base 2 through clamping grooves; or the fixed damping ring 3 is fixed on the two sides of the inner walls of the clamping cover 1 and the base 2 through pins or rivets.
Preferably, the flange seat 5 is uniformly provided with a plurality of through holes 51 for axially mounting the piezoelectric actuators 7, and the number of the through holes 51 is even. The piezoelectric actuator 7 is used for generating acting force to two ends and pushing the movable damping ring 4 to tightly press the fixed damping ring 3; the return spring 6 is used to pull the movable damping ring 4 away from the fixed damping ring 3 after the piezoelectric actuator 7 is unloaded.
In order not to restrict the radial vibration displacement of the rotation shaft 8, the inner diameters of the locking cover 1, the base 2, and the fixed damping ring 3 are larger than the diameter of the rotation shaft 8, and the outer diameters of the movable damping ring 4 and the flange seat 5 are smaller than the inner diameters of the middle sections of the locking cover 1 and the base 2.
The working principle of the dry friction variable damping vibration attenuation device is as follows:
when the dry friction damping device works, driving voltage is applied to the piezoelectric actuator 7, the two ends of the piezoelectric actuator 7 extend outwards to apply force, the movable damping rings 4 on the two sides are pushed to the fixed damping ring 3 to enter a contact state, and dry friction damping is generated. The pressing degree of the movable damping ring 4 and the fixed damping ring 3 can be changed by controlling the driving voltage, so that the contact force is changed to further play a role in adjusting the damping. Because the piezoelectric actuator 7 is arranged in the middle, a set of fixed damping ring 3 and a set of movable damping ring 4 can be arranged on both sides of the piezoelectric actuator, so that the original unidirectional output of the piezoelectric actuator 7 is changed into bidirectional output, and the control action of voltage on damping can be further amplified. After the electrification is cancelled, the movable damping ring 4 and the end surface of the fixed damping ring 3 are quickly restored to a non-contact state under the action of the return spring 6.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from other embodiments.
The embodiments of the present invention are described in detail above with reference to the drawings, but the present invention is not limited to the described embodiments. Various changes, modifications, substitutions and alterations to these embodiments will occur to those skilled in the art without departing from the spirit and scope of the present invention.
Claims (2)
1. A dry friction variable damping vibration damping device, comprising: the clamping cover comprises a clamping cover (1) and a base (2) which are hollow and matched with each other, wherein a fixed damping ring (3), a movable damping ring (4), a flange seat (5) and a return spring (6) are arranged inside the clamping cover (1) and the base (2), the fixed damping ring (3) is fixedly arranged on two sides of the inner wall of the clamping cover (1) and the inner wall of the base (2), the movable damping ring (4) is arranged close to the fixed damping ring (3), the flange seat (5) is arranged between the movable damping rings (4), the return spring (6) is arranged in a clamping position between the movable damping rings (4) and the flange seat (5), two ends of the return spring (6) are respectively and fixedly connected with the movable damping rings (4) and the flange seat (5), the initial state of the return spring (6) is a pre-stretching state, a piezoelectric actuator (7) is arranged in the flange seat (5), and a pair of bearings (9) and a shaft sleeve (10) are arranged between the movable damping rings (4) and the flange seat (5) and a rotating shaft (8);
a pair of fixed damping rings (3) and a pair of movable damping rings (4) are symmetrically arranged in the clamping cover (1) and the base (2), and the fixed damping rings (3) and the movable damping rings (4) are in end surface contact to generate friction damping; the fixed damping ring (3) is fixedly embedded on the clamping cover (1) and two sides of the inner wall of the base (2) through clamping grooves; or the fixed damping ring (3) is fixed on the clamping cover (1) and two sides of the inner wall of the base (2) through pins or rivets;
the flange seat (5) circumference evenly is provided with a plurality of through-holes (51) that are used for along the axial installation piezoelectric actuator (7), the quantity of through-hole (51) is the even number.
2. The dry friction variable damping vibration attenuation device according to claim 1, characterized in that the piezoelectric actuator (7) is used for generating acting force to two ends to push the movable damping ring (4) to press the fixed damping ring (3); the return spring (6) is used for pulling the movable damping ring (4) away from the fixed damping ring (3) after the piezoelectric actuator (7) is unloaded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111084798.9A CN113719543B (en) | 2021-09-16 | 2021-09-16 | Dry friction variable damping vibration damper |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111084798.9A CN113719543B (en) | 2021-09-16 | 2021-09-16 | Dry friction variable damping vibration damper |
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| CN113719543A CN113719543A (en) | 2021-11-30 |
| CN113719543B true CN113719543B (en) | 2022-10-04 |
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