Four-Degree-of-Freedom Parallel Active Fine-Tuning Device for Vibration Isolation of Shipboard Equipment

Abstract

The present invention relates to a four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation, which comprises a fixed base, a moving branch chain, a driving push rod, a rotating branch chain and a supporting platform. A moving branch chain is arranged at the center of the fixed base, and a supporting platform is arranged above the moving branch chain. The driving push rod is arranged between the fixed base and the supporting platform. The lower end of the driving push rod is connected to the fixed base through a universal hinge pair, and its upper end is connected to the limit connecting block on the supporting platform through a spherical pair. The rotating branch chain is arranged between adjacent driving push rods and is fixedly connected to the second disc flange on the moving branch chain. The upper end of the second slider in the rotating branch chain is connected to the limit connecting block on the supporting platform through a spherical pair. The supporting platform of the present invention can realize the vibration isolation fine-tuning movement of shipboard equipment through three-dimensional rotation in space and vertical movement, so as to meet the requirement of maintaining a stable working state of shipboard equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of vibration isolation, and particularly relates to a four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation. Background Art

[0002] Shipboard equipment uses a variety of precision instruments, and these precision instruments usually need to be on a stable platform to achieve more accurate testing, sensing, calibration, etc. For example, the communication system is a communication device fixed on the ship's deck for encrypted communication, and it needs to accurately aim at the satellite under harsh sea conditions and complex vibrations of the ship. The communication system's own ability to stabilize its attitude is not sufficient to compensate for the large swings of the hull, and the vibration requirements for the system's service environment are high, especially for the low-frequency resonance peak.

[0003] Currently, some precision equipment such as scanning electron microscopes, grating ruling machines, quantum communication and other high-precision large-scale equipment have high requirements for stability accuracy and vibration attenuation. Traditional passive vibration damping cannot meet the requirements of high-precision low-frequency vibration damping. Active vibration damping is required to use actuators to provide external energy. On the one hand, it reduces the peak value at low frequencies of the system, and on the other hand, it does not affect the high vibration attenuation rate at medium and high frequencies.

[0004] Waves, strong winds, etc. will cause large attitude changes of the hull and the shipboard communication system to encounter instability. Therefore, the present invention adopts a parallel mechanism and a four-degree-of-freedom parallel active fine-tuning device to compensate for the vibration in four directions of the hull, that is, to compensate for the rotational angles of the three degrees of freedom of roll, pitch, and yaw of the hull and the up and down movement caused by the hull bumping, so that the shipboard equipment can maintain a sufficient stable state on the hull. Summary of the Invention

[0005] Aiming at the problems existing in the prior art, the present invention provides a four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation. The support platform can realize free rotation around three degrees of freedom directions in space. The moving chain is slidably connected through a linear guide rail and a linear chute, and can accurately realize the movement in the vertical direction. At the same time, the rotating chain is a rigid member and can bear a large rotational load, and the moving chain is an elastic member and can play a role in unloading. When the system senses an external disturbance, the driving push rod can actively control the support platform to offset the external excitation so as to achieve the effect of vibration isolation. In addition, the spring is arranged between the second platform and the second disc flange, which can provide a supporting force to balance the self-weight of the device and the influence of external loads, and can also play a role in vibration isolation in the vertical direction. Moreover, the driving push rod only needs a small driving force to realize active fine-tuning vibration isolation, reducing the loss of the driving force of the driving push rod, and can also realize passive vibration isolation in the vertical direction when the driving push rod does not work, thereby reducing energy consumption.

[0006] The technical solution adopted by the present invention is a four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation, which includes a fixed base, a moving branch chain, a driving push rod, a rotating branch chain and a supporting platform. The moving branch chain is arranged at the center of the fixed base, and the supporting platform is arranged above the moving branch chain. The moving branch chain includes a first disc flange, a linear guide rail, a linear sliding groove, a second platform, a spring and a second disc flange. The first disc flange is fixedly arranged on the first platform of the fixed base. The second platform is arranged above the first disc flange, and the linear guide rails are evenly distributed and surrounded between the first disc flange and the second platform. The second disc flange is arranged above the second platform, and the linear sliding grooves are evenly distributed and surrounded in the circumferential direction at the bottom of the second disc flange. The lower end of the linear sliding groove is slidably connected with the linear guide rail, and the spring is arranged between the second platform and the second disc flange. The driving push rod is arranged between the fixed base and the supporting platform, and the driving push rod includes a push rod and a second U-shaped support arranged at the lower end of the push rod. The second U-shaped support at the lower end of the push rod is connected with the first U-shaped support on the fixed base through a cross pin shaft by a universal hinge pair, and the upper end of the push rod is connected with the limit connecting block on the supporting platform through a spherical hinge by a spherical pair. The rotating branch chain is arranged between adjacent driving push rods and is located between the second disc flange and the supporting platform. The rotating branch chain includes a cross support plate, a branch chain support, a sliding connecting plate, a first slider and a second slider. The cross support plate is fixedly connected with the second disc flange, and the branch chain supports are evenly distributed and surrounded on the cross support plate. The upper ends of the branch chain supports are symmetrically provided with arc connecting plates, and the outer sides of the arc connecting plates are provided with first arc guide rails. The first sliders are symmetrically arranged on both sides of the sliding connecting plate, and the first sliders are slidably connected with the first arc guide rails. The upper end surface of the sliding connecting plate is provided with a second arc guide rail, and the second slider is slidably arranged on the second arc guide rail. The upper end of the second slider is connected with the limit connecting block on the supporting platform through a spherical hinge by a spherical pair.

[0007] Further, the fixed base includes a support block, a cross platform, a first U-shaped support and a first platform. The support blocks are evenly distributed and surrounded on the bottom surface of the fixed base, and the cross platform is arranged on the fixed base. The first platform is arranged at the center of the cross platform, and the first U-shaped supports are evenly distributed and surrounded on the fixed base.

[0008] Preferably, the first U-shaped support includes four first U-shaped supports, and the angle between adjacent two first U-shaped supports is 90°. The notch direction of the first U-shaped support faces the center of the fixed base, and the connection line between the center of the fixed base and the central axis of the first U-shaped support is perpendicular to the central axis of the first U-shaped support.

[0009] Furthermore, the support platform includes a driving connection block, a limiting connection block, and a third disc flange. Four driving connection blocks and four limiting connection blocks are arranged around the side surface of the support platform, and the four driving connection blocks and the four limiting connection blocks are arranged alternately at intervals. A third disc flange for installing external equipment is also provided at the middle position of the support platform.

[0010] Preferably, the driving push rods include four groups of driving push rods, the rotating link chains include four groups of rotating link chains, and the four groups of driving push rods and the four groups of rotating link chains are arranged alternately at intervals.

[0011] Preferably, short notch openings and round holes for heat dissipation are respectively provided on the side surface and the back surface of the linear sliding groove.

[0012] Preferably, limiting baffles are provided at both ends of the first arc-shaped guide rail and the second arc-shaped guide rail.

[0013] Preferably, an upper spring clamping groove and a lower spring clamping groove are respectively provided on the upper end surface of the second platform and the lower end surface of the second disc flange, and the lower end of the spring is fixedly connected to the upper spring clamping groove, and the upper end of the spring is fixedly connected to the lower spring clamping groove.

[0014] Preferably, the central axes of the first platform, the first disc flange, the second platform, and the second disc flange coincide.

[0015] The characteristics and beneficial effects of the present invention are as follows:

[0016] 1. A four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation provided by the present invention. The rotating link chain is a rigid member that can bear a large rotating load, and the moving link chain is an elastic member that can play a role in unloading. When the system senses external disturbances, the driving push rods can actively control the support platform to offset external excitations, thereby achieving the effect of vibration isolation.

[0017] 2. A four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation provided by the present invention. The spring is arranged between the second platform and the second disc flange to provide a supporting force, balance the influence of the device's own weight and external loads, and can also play a role in vibration isolation in the vertical direction. Moreover, the driving push rods only need a small driving force to achieve active fine-tuning vibration isolation, reducing the loss of the driving force of the driving push rods. When the driving push rods do not work, passive vibration isolation in the vertical direction can also be achieved, thereby reducing energy consumption.

[0018] 3. A four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation provided by the present invention. The support platform can realize free rotation in three degrees of freedom directions in space. The moving chain is slidably connected through a linear guide rail and a linear chute, and can accurately realize vertical movement. In addition, while the spring realizes unloading, it can also passively offset external excitation disturbances of a certain frequency.

[0019] 4. A four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation provided by the present invention. The rotation center of the support platform is the centroid of the object to be vibration-isolated, and it can realize vibration isolation movement in three degrees of freedom rotation directions in space. At the same time, it avoids the influence of the time-varying gravity when the object to be vibration-isolated rotates, and then reduces the transient amplitude of the moment of inertia of the vibration-isolated equipment caused by external excitation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is the overall structural schematic diagram of the four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation of the present invention;

[0021] Figure 2 is the installation state schematic diagram of the fixed base and the moving chain of the present invention;

[0022] Figure 3 is the structural schematic diagram of the driving push rod of the present invention;

[0023] Figure 4 is the structural schematic diagram of the rotating chain of the present invention;

[0024] Figure 5 is the partial cross-sectional view of the rotating chain of the present invention;

[0025] Figure 6 is the top view of the support platform of the present invention.

[0026] MAIN REFERENCE MARKS:

[0027] Fixed base 1; Support block 11; Cross platform 12; First U-shaped support 13; First platform 14; Moving chain 2; First disc flange 21; Linear guide rail 22; Linear chute 23; Second platform 24; Spring 25; Second disc flange 26; Driving push rod 3; Cross pin 31; Second U-shaped support 32; Push rod 33; Rotating chain 4; Cross support plate 41; Chain support 42; Arc-shaped connecting plate 421; First arc-shaped guide rail 422; Sliding connecting plate 43; Second arc-shaped guide rail 431; First slider 44; Second slider 45; Support platform 5; Driving connection block 51; Limit connection block 52; Third disc flange 53. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0028] To elaborate on the technical content, structural features, achieved objectives and effects of the present invention in detail, the following will be described in detail with reference to the accompanying drawings of the specification.

[0029] The present invention provides a four-degree-of-freedom parallel active fine-tuning device for vibration isolation of shipborne equipment, as Figure 1 shown, which includes a fixed base 1, a moving link 2, a driving push rod 3, a rotating link 4 and a support platform 5.

[0030] As Figure 1 and Figure 2 shown, the fixed base 1 includes a support block 11, a cross platform 12, a first U-shaped support 13 and a first platform 14. Support blocks 11 are evenly distributed and surrounded on the bottom surface of the fixed base 1, and a cross platform 12 is provided on the fixed base 1. A first platform 14 is provided at the center of the cross platform 12, and first U-shaped supports 13 are evenly distributed and surrounded on the fixed base 1. The first U-shaped support 13 includes four first U-shaped supports 13, and the interval between two adjacent first U-shaped supports 13 is 90°. The notch direction of the first U-shaped support 13 faces the center of the fixed base 1, and the connection line between the center of the fixed base 1 and the central axis of the first U-shaped support 13 is perpendicular to the central axis of the first U-shaped support 13.

[0031] As Figure 2 shown, a moving link 2 is provided at the center of the fixed base 1, and a support platform 5 is provided above the moving link 2. The moving link 2 includes a first disc flange 21, a linear guide rail 22, a linear chute 23, a second platform 24, a spring 25 and a second disc flange 26. The first disc flange 21 is fixedly provided on the first platform 14 of the fixed base 1. The second platform 24 is provided above the first disc flange 21, and linear guide rails 22 are evenly distributed and surrounded between the first disc flange 21 and the second platform 24. The lower end of the linear guide rail 22 is connected to the first disc flange 21, and the upper end of the linear guide rail 22 is connected to the second disc flange 26. The second disc flange 26 is provided above the second platform 24, and linear chutes 23 are evenly distributed and surrounded in the circumferential direction at the bottom of the second disc flange 26. The lower end of the linear chute 23 is slidably connected to the linear guide rail 22, and the spring 25 is provided between the second platform 24 and the second disc flange 26. Short notch openings and round holes for heat dissipation are respectively provided on the side and back of the linear chute 23.

[0032] In a preferred manner, an upper spring slot and a lower spring slot are respectively provided on the upper end surface of the second platform 24 and the lower end surface of the second disc flange 26, and the lower end of the spring 25 is fixedly connected to the upper spring slot, and the upper end of the spring 25 is fixedly connected to the lower spring slot.

[0033] As Figure 3As shown in the figure, the driving push rod 3 is arranged between the fixed base 1 and the support platform 5. The driving push rod 3 includes a push rod 33 and a second U-shaped support 32 arranged at the lower end of the push rod 33. The second U-shaped support 32 at the lower end of the push rod 33 is connected to the first U-shaped support 13 on the fixed base 1 through a cross pin shaft 31 by means of a universal hinge pair, and the upper end of the push rod 33 is connected to the limit connection block 52 on the support platform 5 through a ball hinge by means of a ball pair.

[0034] As Figure 4 and Figure 5 shown in the figure, the rotating chain 4 is arranged between adjacent driving push rods 3 and is located between the second disc flange 26 and the support platform 5. The rotating chain 4 includes a cross support plate 41, a chain support 42, a sliding connection plate 43, a first slider 44 and a second slider 45. The cross support plate 41 is fixedly connected to the second disc flange 26, and the chain supports 42 are evenly arranged around the cross support plate 41 in a circumferential manner. The upper ends of the chain supports 42 are symmetrically provided with arc connection plates 421, and the outer sides of the arc connection plates 421 are provided with first arc guide rails 422. The two sides of the sliding connection plate 43 are symmetrically provided with first sliders 44, and the first sliders 44 are slidably connected to the first arc guide rails 422. The upper end surface of the sliding connection plate 43 is provided with a second arc guide rail 431, and a second slider 45 is slidably arranged on the second arc guide rail 431. The upper end of the second slider 45 is connected to the limit connection block 52 on the support platform 5 through a ball hinge by means of a ball pair.

[0035] In a preferred embodiment, the driving push rod 3 includes four groups of driving push rods 3, the rotating chain 4 includes four groups of rotating chains 4, and the four groups of driving push rods 3 and the four groups of rotating chains 4 are arranged alternately at intervals in sequence.

[0036] In a preferred embodiment, limit baffles are provided at both ends of the first arc guide rail 422 and the second arc guide rail 431.

[0037] As Figure 6 shown in the figure, the support platform 5 includes a driving connection block 51, a limit connection block 52 and a third disc flange 53. Four driving connection blocks 51 and four limit connection blocks 52 are arranged around the side surface of the support platform 5 in a circumferential manner, and the four driving connection blocks 51 and the four limit connection blocks 52 are arranged alternately at intervals in sequence. A third disc flange 53 for installing external equipment is further provided at the middle position of the support platform 5.

[0038] In a preferred embodiment, the central axes of the first platform 14, the first disc flange 21, the second platform 24 and the second disc flange 26 coincide.

[0039] The specific operation steps of the present invention are as follows:

[0040] As Figures 1 to 6As shown in the figure, a four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation. The fixed base 1 is fixedly installed on the shipboard workbench, and the vibration-isolated instrument is fixedly installed on the third disc flange 53 of the support platform 5. When the instrument is in a static state, the load of the instrument is absorbed by the spring 25, and the driving push rod 3 does not provide driving force. When the external excitation received by the instrument is a vertical excitation and the excitation frequency is greater than a multiple of the natural frequency of the spring 25, the spring 25 can play a passive vibration isolation effect while balancing the equipment load. The driving push rod 3 can provide a certain driving force to the support platform 5 according to the feedback signal of the sensor to offset the residual excitation to keep the equipment stable. When the hull is affected by waves, strong winds, etc. resulting in large attitude changes of the hull, the device needs to compensate for the rotation of the hull in three degrees of freedom, namely roll, pitch, and yaw, and the up and down movement caused by the hull bump. The driving push rod 3 offsets the external excitation by controlling the different elongation amounts of the four push rods 33 according to the signal real-time feedback by the sensor; the four driving push rods 3 are helically and obliquely distributed uniformly between the fixed base 1 and the support platform 5. The control methods of the driving push rod 3 in different situations are as follows:

[0041] (1) When the support platform 5 is horizontally stationary, the telescopic lengths of the four push rods 33 are equal and unchanged.

[0042] (2) When the support platform 5 needs to offset the bump excitation, the driving push rod 3 can be realized by controlling the four push rods 33 to extend or shorten the same length according to the real-time feedback signal of the sensor.

[0043] (3) When the support platform 5 needs to offset the yaw excitation, the driving push rod 3 can be realized by controlling the different elongation or shortening lengths of each push rod 33 according to the real-time feedback signal of the sensor.

[0044] (4) When the support platform 5 needs to offset the roll and pitch excitations, the driving push rod 3 can be realized by controlling two push rods 33 to extend or shorten and keeping the lengths of the other two push rods 33 unchanged according to the real-time feedback signal of the sensor.

[0045] The above-described embodiments are only descriptions of the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various deformations and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. A four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation, characterized in that It includes a fixed base, a moving chain, a driving push rod, a rotating chain and a supporting platform. The moving chain is arranged at the center of the fixed base, and the supporting platform is arranged above the moving chain. The moving chain includes a first disc flange, a linear guide rail, a linear chute, a second platform, a spring and a second disc flange. The first disc flange is fixedly arranged on the first platform of the fixed base. The second platform is arranged above the first disc flange, and the linear guide rails are evenly distributed and surrounded between the first disc flange and the second platform. The second disc flange is arranged above the second platform, and the linear chutes are evenly distributed and surrounded in the circumferential direction at the bottom of the second disc flange. The lower end of the linear chute is slidably connected with the linear guide rail, and the spring is arranged between the second platform and the second disc flange. The driving push rod is arranged between the fixed base and the supporting platform. The driving push rod includes a push rod and a second U-shaped support arranged at the lower end of the push rod. The second U-shaped support at the lower end of the push rod is connected with the first U-shaped support on the fixed base through a cross pin shaft by a universal hinge pair, and the upper end of the push rod is connected with the limit connection block on the supporting platform through a spherical hinge by a spherical pair. The rotating chain is arranged between adjacent driving push rods and is located between the second disc flange and the supporting platform. The rotating chain includes a cross support plate, a chain support, a sliding connecting plate, a first slider and a second slider. The cross support plate is fixedly connected with the second disc flange, and the chain supports are evenly distributed and surrounded on the cross support plate. The upper ends of the chain supports are symmetrically provided with arc connecting plates. The outer side of the arc connecting plate is provided with a first arc guide rail. The first sliders are symmetrically arranged on both sides of the sliding connecting plate, and the first sliders are slidably connected with the first arc guide rail. The upper end surface of the sliding connecting plate is provided with a second arc guide rail. The second slider is slidably arranged on the second arc guide rail, and the upper end of the second slider is connected with the limit connection block on the supporting platform through a spherical hinge by a spherical pair.

2. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, characterized in that, The fixed base includes a support block, a cross platform, a first U-shaped support and a first platform. The support blocks are evenly distributed and surrounded on the bottom surface of the fixed base. The cross platform is arranged on the fixed base. The first platform is arranged at the center of the cross platform, and the first U-shaped supports are evenly distributed and surrounded on the fixed base.

3. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 2, wherein The first U-shaped support includes four first U-shaped supports, and the interval between adjacent two first U-shaped supports is 90°. The notch direction of the first U-shaped support is facing the center of the fixed base, and the connection line between the center of the fixed base and the central axis of the first U-shaped support is perpendicular to the central axis of the first U-shaped support.

4. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, characterized in that, The support platform includes a driving connection block, a limiting connection block, and a third disc flange. Four driving connection blocks and four limiting connection blocks are arranged in a circular manner on the side surface of the support platform, and the four driving connection blocks and the four limiting connection blocks are alternately arranged at intervals. A third disc flange for installing external equipment is also provided at the middle position of the support platform.

5. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, characterized in that, The driving push rod includes four groups of driving push rods, the rotating chain includes four groups of rotating chains, and the four groups of driving push rods and the four groups of rotating chains are alternately arranged at intervals.

6. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, characterized in that Short notch openings and round holes for heat dissipation are respectively provided on the side surface and the back surface of the linear sliding groove.

7. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, wherein Limit baffles are provided at both ends of the first arc-shaped guide rail and the second arc-shaped guide rail.

8. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, characterized in that An upper spring clamping groove and a lower spring clamping groove are respectively provided on the upper end surface of the second platform and the lower end surface of the second disc flange. The lower end of the spring is fixedly connected to the upper spring clamping groove, and the upper end of the spring is fixedly connected to the lower spring clamping groove.

9. The four-degree-of-freedom parallel active fine-tuning device for shipboard equipment vibration isolation according to claim 1, characterized in that, The central axes of the first platform, the first disc flange, the second platform, and the second disc flange coincide.

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