Lifting rotation positioning device for vector hydrophone calibration

Abstract

The utility model discloses a lifting rotary positioning device for vector hydrophone calibration, and belongs to the field of underwater acoustic calibration. The device comprises a lifting motion mechanism, a rotary motion mechanism and a calibration cavity. The lifting motion mechanism comprises a motor driving module, a trapezoidal lead screw pair, a linear track bearing pair, an upper plate, a bottom plate and a lifting plate. The rotary motion mechanism comprises a motor driving module, a right-angle reversing module, a thin-wall bearing, a hook and a thin-wall bearing supporting frame. The thin-wall bearing comprises a small gear, a large gear, an inner ring, an outer ring and balls. The calibration cavity is a hollow cylinder and is used for obtaining an experimental environment for vector hydrophone calibration and test data; the lifting motion mechanism is mounted on the upper surface of the calibration cavity, and the rotary motion mechanism is mounted on the lifting motion mechanism; the lifting motion mechanism is used for moving the rotary motion mechanism up and down. The device has two mechanical motion freedom degrees of lifting and rotation, can realize high-precision automatic position positioning control, and realizes automatic adjustment of an underwater test angle.

Description

Technical Field

[0001] This invention belongs to the field of underwater acoustic calibration and relates to a test device for calibrating vector hydrophones, which is used to accurately position the vector hydrophone being calibrated in the lifting and angular directions during the calibration test. Background Technology

[0002] With the development of underwater acoustic technology, vector hydrophones are increasingly being used in underwater acoustic measurement and are gradually being applied to military equipment. A typical vector hydrophone consists of vector sensors (accelerometers, displacement sensors, sound pressure gradient sensors, etc.) and a sound pressure sensor. This allows the vector hydrophone to simultaneously obtain scalar (sound pressure) and vector (particle velocity, acceleration, sound pressure gradient, etc.) information at a point in the sound field. Vector hydrophones significantly expand the database of sound field characteristic parameters, making vector sensors a promising candidate for applications in marine information measurement systems, underwater acoustic navigation equipment, marine geological surveys, and sound intensity measurements.

[0003] The commonly used method for calibrating vector hydrophones is the comparison method employed in underwater acoustic standing wave tubes. The schematic diagram of the calibration device can be found here. Figure 5 The transmitting transducer is located at the bottom of the calibration tube and is excited by a power amplifier to emit sound waves vertically upwards within the tube, establishing a standing wave sound field. The standard hydrophone and the vector hydrophone under calibration are placed at known positions above the water surface as shown in the diagram. Because the sound field within the tube is a standing wave, the sound pressures measured by the standard hydrophone and the vector hydrophone under calibration satisfy a certain functional relationship. By measuring the sound pressure at the location of the standard hydrophone, the sensitivity of the vector hydrophone under calibration can be calculated. Since the sound field within the tube is vertically distributed, if the vector hydrophone under calibration is rotated along the horizontal axis, and the rotation angle and the open-circuit voltage of the vector hydrophone are recorded, the directivity pattern of the vector hydrophone can be obtained.

[0004] As can be seen from the above calibration principle, the calibration process of a vector hydrophone requires an experimental testing auxiliary device to accurately position and angle the vector hydrophone being calibrated in order to obtain accurate test data. At the same time, because the steel structure will reflect sound waves in the underwater environment, this will affect the accuracy of the underwater acoustic test (the amount of influence is basically proportional to the volume of the steel structure). Therefore, the mechanical structure, especially the metal structure that is submerged in water, should be as small and compact as possible to minimize the impact on the sound field test.

[0005] As a non-standard, specialized testing device, there are currently no standard lifting and rotating auxiliary devices or specifications in the industry. Some of the devices commonly used by scientific researchers are simple structures with fully manual adjustment, relying entirely on manual operation to measure height and angle positions; some automated devices use a wire rope pulling drive for lifting and rotating structures, but the disadvantages are low positioning accuracy and the inability to achieve a full 360° rotation.

[0006] In summary, there is currently no fully automated auxiliary positioning device in the industry that meets the requirements for lifting and rotating operations, and is of high precision, for vector hydrophone calibration testing. Utility Model Content

[0007] To meet the calibration requirements of vector hydrophones, the purpose of this invention is to provide a lifting and rotating positioning device for vector hydrophone calibration. This device, used for auxiliary positioning of vector hydrophones in underwater acoustic standing wave tubes, has two degrees of freedom: lifting and rotation, enabling high-precision automated position control. This invention achieves automatic adjustment of the water depth by mounting the vector hydrophone to be calibrated in a circular clamp on a vertical plane and driving its lifting motion within the calibration chamber, and automatic adjustment of the underwater testing angle by performing full or multiple rotations around a horizontal axis within the vertical mounting plane.

[0008] The objective of this utility model is achieved through the following technical solution:

[0009] This utility model discloses a lifting and rotating positioning device for vector hydrophone calibration, comprising a lifting mechanism, a rotating mechanism, and a calibration chamber. The calibration chamber is a hollow cylinder, used as the experimental environment for vector hydrophone calibration and for acquiring test data; the lifting mechanism is mounted on the upper surface of the calibration chamber, and the rotating mechanism is mounted on the lifting mechanism. The rotating mechanism can enter and exit the hollow part of the calibration chamber and can also rotate within the calibration chamber; the lifting mechanism is used for the up-and-down movement of the rotating mechanism.

[0010] The lifting mechanism includes a motor drive module, a trapezoidal lead screw pair, a linear guide bearing pair, an upper plate, a base plate, and a lifting plate. The base plate forms the foundation of the lifting mechanism, with four linear guide rail pairs mounted on it. The upper plate is mounted on top of the linear guide rail pairs, together supporting the entire frame structure. The trapezoidal lead screw pair is installed in the center of the lifting mechanism, and its rotation is driven by the motor drive module mounted on the upper plate, thereby driving the lifting plate to move up and down. The motor drive module mainly consists of a motor and a worm gear reducer.

[0011] The rotary motion mechanism includes a motor drive module, a right-angle reversing module, a thin-walled bearing, a hook, and a thin-walled bearing support frame. The motor drive module is connected and installed to the thin-walled bearing via the thin-walled bearing support frame; the driving force is transmitted from the motor drive module to the thin-walled bearing through the right-angle reversing module; the hook is used to install the vector hydrophone.

[0012] The thin-walled bearing consists of a pinion, a large gear inner ring, an outer ring, and balls. The outer ring has two ball tracks on its inner wall, and the large gear inner ring has two corresponding ball tracks. The balls are fitted into the tracks of the outer ring and the large gear inner ring to guide the rotational motion. The outer ring is fixed on the thin-walled bearing support frame. The pinion is connected to a right-angle reversing module, and the rotation of the pinion drives the rotation of the large gear inner ring.

[0013] The right-angle reversing module transmits motion and power to two intersecting shafts that are 90° apart. The reversing function is achieved internally by installing a pair of small bevel gears. A small gear can be installed on the output shaft section of the right-angle reversing module to mesh with the inner ring of the large gear in a thin-walled bearing for transmission.

[0014] Beneficial effects:

[0015] 1. This utility model discloses a lifting and rotating positioning device for vector hydrophone calibration. The rotating mechanism adopts a thin-walled bearing structure. The thin-walled bearing is based on a standard four-point contact thin-walled bearing, with the inner ring designed as a large gear ring. This integrates the rotating motion guide structure—the thin-walled bearing body (grooves of inner and outer rings, cage, rolling elements, etc.)—with the transmission structure (large and small gears) into one, resulting in high rotational guiding transmission positioning accuracy and good repeatability. It also allows for a compact structure, thin walls and width, and the use of corrosion-resistant materials to adapt to underwater working environments.

[0016] 2. The present invention discloses a lifting and rotating positioning device for calibrating a vector hydrophone. The driving transmission path of the rotating motion is as follows: the motor transmits the driving force to the pinion through a worm gear reducer and then through a right-angle reversing mechanism. Finally, the inner ring of the bearing (large gear ring) on ​​which the vector hydrophone to be calibrated is installed is driven to rotate. In this way, the power is transmitted from the surface to the underwater. The rotating motion can realize the reciprocating rotation of the vector hydrophone to be calibrated for a full circle or multiple circles, without any dead angles in the test.

[0017] 3. The present invention discloses a lifting and rotating positioning device for vector hydrophone calibration. The lifting motion mechanism drives the lead screw to rotate through the motor drive module. The four sets of linear track bearing pairs serve as both guides and transmission structures. The lifting motion mechanism has the advantages of compact structure and high guiding and transmission accuracy.

[0018] 4. The present invention discloses a lifting and rotating positioning device for calibrating a vector hydrophone. The lifting motion mechanism is directly installed on the calibration cavity and can drive the vector hydrophone being calibrated to move up and down along the central axis of the calibration cavity, thereby achieving high-precision positioning inside the cavity (underwater). Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the lifting and rotating positioning device for vector hydrophone calibration according to this utility model;

[0020] The attached diagram is labeled as follows: 1-lifting mechanism, 2-rotation mechanism, 3-calibration cavity.

[0021] Figure 2 This is a schematic diagram of the lifting mechanism of this utility model;

[0022] The attached diagram is labeled as follows: 4-motor drive module A, 5-trapezoidal lead screw pair, 6-linear track bearing pair, 7-upper plate, 8-bottom plate, 9-lifting plate.

[0023] Figure 3 This is a schematic diagram of the rotary motion mechanism of this utility model;

[0024] The attached diagram is labeled as follows: 10-motor drive module B, 11-right-angle reversing module, 12-thin-walled bearing, 13-hook, 14-thin-walled bearing support frame.

[0025] Figure 4 This is a schematic diagram of the thin-walled bearing structure of this utility model;

[0026] The attached diagram is labeled as follows: 15-small gear, 16-inner ring of large gear, 17-outer ring, 18-ball bearing.

[0027] Figure 5 This is a block diagram illustrating the principle of vector hydrophone calibration.

[0028] The attached figures are labeled as follows: 3-calibration cavity, 12-thin-walled bearing, 19-vector hydrophone, 20-standard hydrophone, 21-transmitting transducer. Detailed Implementation

[0029] To better illustrate the purpose and advantages of this utility model, the following description, in conjunction with the accompanying drawings and examples, will further explain the content of the utility model.

[0030] Example 1:

[0031] This embodiment discloses a lifting and rotating positioning device for vector hydrophone calibration, including a lifting motion mechanism 1, a rotating motion mechanism 2, and a calibration chamber 3. Figure 1As shown, calibration cavity 3 is a hollow cylinder, used as the experimental environment for vector hydrophone calibration and for acquiring test data; lifting mechanism is installed on the upper surface of calibration cavity 3, and rotary mechanism 2 is installed on lifting mechanism 1. Rotary mechanism 2 can enter and exit the hollow part of calibration cavity 3, and can also rotate inside calibration cavity 3; lifting mechanism 1 is used for the up and down movement of rotary mechanism 2.

[0032] The lifting mechanism 1 includes a motor drive module A4, a trapezoidal lead screw pair 5, a linear track bearing pair 6, an upper plate 7, a base plate 8, and a lifting plate 9. For example... Figure 2 As shown, the base plate 8 is the foundation of the lifting mechanism 1. Four linear guide rail pairs 6 are installed on the base plate 8, and the upper plate 7 is installed on top of the linear guide rail pairs 6, together supporting the entire frame structure. The trapezoidal lead screw pair 5 is installed in the middle of the lifting mechanism 1, and is driven to rotate by the motor drive module installed on the upper plate 7, thereby driving the lifting plate 9 to move up and down. The motor drive module A4 mainly consists of a motor and a worm gear reducer.

[0033] The rotary motion mechanism 2 includes a motor drive module B10, a right-angle reversing module 11, a thin-walled bearing 12, a hook 13, and a thin-walled bearing support frame 14. For example... Figure 3 As shown, the motor drive module is connected and installed to the thin-walled bearing 12 via a thin-walled bearing support frame; the driving force is transmitted from the motor drive module B10 to the thin-walled bearing 12 via the right-angle reversing module 11; the hook 13 is used to install the vector hydrophone.

[0034] The thin-walled bearing 12 comprises a pinion 15, a large gear inner ring 16, an outer ring 17, and balls 18. (Example) Figure 4 As shown, the inner wall of the outer ring 17 has two rings of ball tracks, and the inner ring 16 of the large gear has two corresponding rings of ball tracks 18. The balls 18 are fitted into the tracks of the outer ring 17 and the inner ring 16 of the large gear to guide the rotational motion. The outer ring 17 is fixed on the support frame of the thin-walled bearing 12, and the pinion 15 is connected to the right-angle reversing module 11. The rotation of the pinion 15 drives the inner ring 17 of the large gear to rotate.

[0035] The thin-walled bearing slewing ring structure is the most critical structure of this invention. Taking a calibration cavity with a diameter of 300mm as an example, the outer diameter of the thin-walled bearing 12 is 290mm, the wall thickness of the slewing ring is 30mm, and the height is 20mm. The dimensions in both directions are reduced by 3-5mm compared to the previous version of the experimental equipment (slewing ring driven by wire rope), and the total volume is reduced by 15%. According to the law that the reflectivity of the water acoustic field is proportional to the volume of the metal structure, this will significantly reduce the influence of the structure on the acoustic field test.

[0036] The right-angle reversing module 11 transmits motion and power to two intersecting shafts that are 90° apart. The reversing function is achieved by installing a pair of small bevel gears inside the right-angle reversing module 11. A small gear 15 can be installed on the output shaft section of the right-angle reversing module 11 to mesh with the inner ring 16 of the large gear of the thin-walled bearing 12 for transmission.

[0037] The calibration chamber 3 is a cylindrical, thick-walled stainless steel water tank, i.e., a water acoustic standing wave tube, which provides a calibration environment for the vector hydrophone. The calibration chamber 3 is filled with pure water.

[0038] To adapt to humid operating environments, the trapezoidal lead screw assembly 5 and the linear track bearing assembly 6 are made of stainless steel.

[0039] To adapt to humid operating environments, the thin-walled bearing support frame 14, right-angle reversing module 11, pinion 15, and thin-walled bearing 12 are made of stainless steel.

[0040] The thin-walled bearing support frame 14 has four positioning threaded holes at the top for connection with the worm gear reducer; the thin-walled bearing support frame 14 has two square connecting plates in the middle for connection with the right-angle reversing module 11; the bottom of the thin-walled bearing support frame 14 is arc-shaped, which can ensure good connection of the outer ring of the thin-walled bearing 12; in addition, the thin-walled bearing support frame 14 has a space inside to install a small gear 15 to transmit power.

[0041] This embodiment discloses a method for operating a lifting and rotating positioning device for vector hydrophone calibration, that is, using this device to assist a vector hydrophone calibration system in calibration work, the working steps of which are as follows:

[0042] First step, according to Figure 5 Water is injected into the calibration chamber 3, and a standard hydrophone 20 and a transmitting transducer 21 are arranged there.

[0043] The second step is to return to the initial state: The initial state of the lifting and rotating positioning device used for vector hydrophone calibration is as follows... Figure 1 As shown. At this time, the lifting mechanism 1 is at its highest point in the lifting direction, that is, the rotary mechanism 2 installed on the lifting plate 9 is completely above the water surface in the calibration chamber 3. If the rotary mechanism 2 is still submerged in water at this time, the motor drive module A4 on the lifting mechanism 1 will operate to return it to its original position. Figure 1 The initial state.

[0044] The second step is to install the vector hydrophone 19 to be calibrated: In the initial state, the lifting mechanism 1 installs the vector hydrophone 19 on the inner ring of the thin-walled bearing 12. The vector hydrophone 19 to be calibrated can be suspended at the center of the inner ring through the hook on the inner ring. The acoustic center of the vector hydrophone 19 coincides with the geometric center of the thin-walled bearing 12.

[0045] The third step involves the vector hydrophone 19 entering the water: The motor drive module A4 on the lifting mechanism 1 operates, causing the lifting plate 9 to lower the thin-walled bearing 12 and the vector hydrophone 19 into the test position below the water surface within the calibration chamber 3. At this point, the vector hydrophone calibration system can operate, collecting data from the vector hydrophone 19 to calibrate its sensitivity. Since the calibration data results are directly related to the lifting and positioning accuracy, this invention can achieve high-precision acoustic calibration.

[0046] The fourth step is rotational motion: The motor drive module A4 on the rotational motion mechanism 2 is activated, causing the gear mechanism to drive the vector hydrophone 19 on the inner ring of the thin-walled bearing 12 to rotate around its acoustic center. At this time, the vector hydrophone calibration system can operate, simultaneously collecting data from the vector hydrophone 19 and rotation angle data for calibrating its directivity. Since the calibration data results are directly related to the rotational positioning accuracy, this invention can achieve high-precision acoustic calibration.

[0047] Fifth step: After calibration, control the motor drive module A4 on the lifting mechanism 1 to raise the lifting plate 9 and return it to its initial state. Remove the vector hydrophone 19.

[0048] The above detailed description further illustrates the purpose, technical solution, and beneficial effects of the utility model. It should be understood that the above description is only a specific embodiment of the present utility model and is not intended to limit the scope of protection of the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the scope of protection of the present utility model.

Claims

1. A lifting and rotating positioning device for vector hydrophone calibration, characterized in that: It includes a lifting motion mechanism (1), a rotary motion mechanism (2), and a calibration chamber (3); the calibration chamber (3) is a hollow cylinder used as the experimental environment for vector hydrophone calibration and for acquiring test data; the lifting motion mechanism is installed on the upper surface of the calibration chamber (3), and the rotary motion mechanism (2) is installed on the lifting motion mechanism (1). The rotary motion mechanism (2) can enter and exit the hollow part of the calibration chamber (3) and can also rotate inside the calibration chamber (3); the lifting motion mechanism (1) is used for the up and down movement of the rotary motion mechanism (2).

2. The lifting and rotating positioning device for vector hydrophone calibration as described in claim 1, characterized in that: The lifting mechanism (1) includes a motor drive module A (4), a trapezoidal lead screw pair (5), a linear rail bearing pair (6), an upper plate (7), a base plate (8), and a lifting plate (9). The base plate (8) is the foundation of the lifting mechanism (1). Four linear rail bearing pairs (6) are installed on the base plate (8), and the upper plate (7) is installed on top of the linear rail bearing pairs (6), together supporting the entire frame structure. The trapezoidal lead screw pair (5) is installed in the middle of the lifting mechanism (1). The motor drive module installed on the upper plate (7) drives the lead screw to rotate, thereby driving the lifting plate (9) to move up and down. The motor drive module A (4) is mainly composed of a motor and a worm gear reducer.

3. The lifting and rotating positioning device for vector hydrophone calibration as described in claim 1, characterized in that: The rotary motion mechanism (2) includes a motor drive module B (10), a right-angle reversing module (11), a thin-walled bearing (12), a hook (13), and a thin-walled bearing support frame (14); the motor drive module is connected and installed to the thin-walled bearing (12) through the thin-walled bearing support frame; the driving force is transmitted from the motor drive module B (10) to the thin-walled bearing (12) through the right-angle reversing module (11); the hook (13) is used to install the vector hydrophone; The thin-walled bearing (12) consists of a pinion (15), a large gear inner ring (16), an outer ring (17), and balls (18). The inner wall of the outer ring (17) has two rings of ball tracks, and the large gear inner ring (16) has two corresponding rings of ball (18) tracks. The balls (18) are fitted into the tracks of the outer ring (17) and the large gear inner ring (16) to guide the rotational motion. The outer ring (17) is fixed on the thin-walled bearing (12) support frame. The pinion (15) is connected to the right-angle reversing module (11). The rotation of the pinion (15) drives the rotation of the large gear inner ring (16).

4. The lifting and rotating positioning device for vector hydrophone calibration as described in claim 3, characterized in that: The right-angle reversing module (11) transmits motion and power to two intersecting shafts that are 90° apart. The right-angle reversing module (11) realizes the reversing function by installing a pair of small bevel gears inside. A small gear (15) can be installed on the output shaft section of the right-angle reversing module (11) to mesh with the inner ring (16) of the large gear of the thin-walled bearing (12).

5. The lifting and rotating positioning device for vector hydrophone calibration as described in claim 1, characterized in that: The calibration chamber (3) is a cylindrical thick-walled stainless steel water tank, i.e., a water acoustic standing wave tube, which provides a calibration environment for the vector hydrophone. The calibration chamber (3) is filled with pure water.

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