A force and acceleration composite sensor and adjustment method

Abstract

The present invention is a force and acceleration composite sensor and adjustment method, belonging to the field of sensors. Its technical solution is as follows: a force and acceleration composite sensor includes a sensor housing, an acceleration detection component includes an acceleration detection core, the sensor housing has a first positioning surface and a first pressure block, the acceleration detection core is located between the first positioning surface and the first pressure block, a tightening screw is provided on the first pressure block, the sensor housing has a first threaded hole, and the tightening screw is threadedly connected to the first threaded hole; the force detection component includes a force detection core, the sensor housing also has a second positioning surface and a second pressure block, the force detection core is located between the second positioning surface and the second pressure block, and a jack assembly is provided on the side of the second pressure block facing away from the force detection core. This solution adds an adjustable pressure block structure to achieve preload adjustment; the rigid connection form of the threaded connection avoids the rebound phenomenon, making the preload more stable and accurate.

Description

Technical Field

[0001] The present invention relates to the field of sensors, in particular to a force and acceleration composite sensor and an adjustment method for the force and acceleration composite sensor. Background Art

[0002] Piezoelectric accelerometers and piezoelectric force sensors use piezoelectric materials as their sensitive elements. An accelerometer is a sensor capable of measuring acceleration and typically consists of a mass, an elastic element, and a sensitive element. During acceleration, the sensor measures the inertial force acting on the mass under the action of an external force and uses Newton's second law to determine the acceleration value. A force sensor is a device or apparatus that can sense tension or compression signals and convert them into a usable output electrical signal according to a specific pattern. Both types of sensors are used in numerous industries, including water conservancy and hydropower, railway transportation, intelligent buildings, production automation, aerospace, military industry, petrochemicals, oil wells, power generation, shipbuilding, machine tools, pipelines, and more.

[0003] Specifically, the detection components of piezoelectric force sensors and acceleration sensors are composed of multiple layers of lithium niobate crystals and electrode sheets stacked together, and a certain pre-pressure is applied. When a vibration signal is generated on the sensor surface, the tensile, compressive or shear stress generated by the mass block will directly act on the lithium niobate crystal element, causing the piezoelectric element to generate an electric charge, thereby outputting an electrical signal.

[0004] Therefore, the size of the pre-stress determines the performance of the sensor. However, during the current production of sensors, the pressurized components are welded and fixed after the pre-stress is applied. On the one hand, the pre-stress is fixed after welding and can only be used in specific environments, with poor versatility. On the other hand, since the pre-stress is usually in the tons level, the weld can hardly withstand a large pre-stress, and the pressurized components are prone to rebound after welding, resulting in pre-stress distortion. Summary of the Invention

[0005] The present invention aims to solve the problem that the pre-pressure of the current force and acceleration composite sensor is fixed and easily distorted due to the rebound of the pressurized component, and provides a force and acceleration composite sensor and its adjustment method.

[0006] To solve the above problems, the technical solution adopted by the present invention is: a force and acceleration composite sensor, comprising a sensor housing, an acceleration detection component and a force detection component installed inside the sensor housing: the acceleration detection component comprises an acceleration detection core, the sensor housing has a first positioning surface and a first pressure block, the acceleration detection core is located between the first positioning surface and the first pressure block, a tightening screw is fixedly arranged on the first pressure block, the sensor housing has a first threaded hole, the tightening screw passes through the acceleration detection core and is threadedly connected to the first threaded hole of the sensor housing, and the end of the tightening screw located outside the sensor housing is provided with a first rotating operating structure; the force detection component comprises a force detection core, the sensor housing also has a second positioning surface and a second pressure block, the force detection core is located between the second positioning surface and the second pressure block, a jack assembly is provided on the side of the second pressure block facing away from the force detection core, and the operating end of the jack assembly is located outside the sensor housing. This solution adds an adjustable pressure block structure to the force and acceleration composite sensor. The pressure of the first pressure block on the acceleration detection core is adjusted by twisting the tightening screw, and the tightening force of the second pressure block on the force detection core is adjusted by the jack assembly, thereby realizing the adjustment of the pre-pressure of the two and improving the versatility of the sensor. At the same time, the rigid connection form of the threaded connection avoids the rebound phenomenon and makes the pre-pressure more stable and accurate.

[0007] As a preferred implementation scheme for a force and acceleration composite sensor, the jack assembly includes a forward and reverse rotating screw, and a connecting block is respectively installed on the two sections of the thread of the forward and reverse rotating screw through a thread. Two connecting rods are hingedly installed on each connecting block and are respectively located on the upper and lower sides of the forward and reverse rotating screw. The two connecting rods located above the forward and reverse rotating screw are hingedly installed with an upper top block, and the two connecting rods located below the forward and reverse rotating screw are hingedly installed with a lower top block. The upper top block contacts the second pressure block, and the lower top block contacts the inner wall of the sensor housing. The outer wall of the sensor housing is provided with a long hole, and one end of the forward and reverse rotating screw passes through the long hole and is located outside the sensor housing. The end is provided with a second rotating operating structure. The jack assembly can achieve accurate and stable adjustment of the pre-pressure of the force detection core. Compared with the traditional welding fixing method, its adjustment is more flexible.

[0008] As a preferred implementation scheme of a force and acceleration composite sensor, the sensor housing includes an upper base, the upper base includes an upper cover plate, a mounting seat is provided on the bottom surface of the upper cover plate, a mounting cavity is provided on one side of the mounting seat, and in the depth direction of the mounting cavity, the bottom surface of the mounting cavity is the first positioning surface and is provided with a second threaded hole, the acceleration detection core and the first pressure block are both located in the mounting cavity, the tightening screw passes through the second threaded hole and is threadedly engaged with the second threaded hole. The upper base provides a stable installation space and a precise positioning reference for the acceleration detection component, which can ensure the accuracy of the installation position of the acceleration detection core and ensure that the preload is evenly applied to the core. At the same time, the threaded engagement of the tightening screw with the second threaded hole realizes the adjustability of the preload and is convenient for installation and disassembly.

[0009] As a preferred implementation scheme for a force and acceleration composite sensor, the acceleration detection core includes a first electrode sheet, two first lithium niobate crystal sheets, and two mass blocks. The two first lithium niobate crystal sheets are located on either side of the first electrode sheet, and the mass block is located on the side of the first lithium niobate crystal sheet facing away from the first electrode sheet. The first electrode sheet, the first lithium niobate crystal sheet, and the mass block are all annular. An insulating sleeve is provided on the tightening screw. The first electrode sheet, the first lithium niobate crystal sheet, and the mass block are sleeved on the outer circumference of the insulating sleeve. The use of the annular first electrode sheet, the first lithium niobate crystal sheet, and the mass block makes force transmission more uniform, improving the sensitivity and stability of the sensor for acceleration detection. The provision of the insulating sleeve avoids problems such as electrical short circuits, ensuring the normal operation of the sensor. It also enhances the integrity and reliability of the core structure and reduces detection errors caused by component displacement.

[0010] As a preferred implementation of a force and acceleration composite sensor, the bottom surface of the mounting base is flat and serves as the second positioning surface. The force detection core includes two second electrode sheets and two second lithium niobate crystal sheets, which are stacked at intervals, with the second electrode sheet located at the bottom layer and in contact with the second pressure block. The second pressure block is made of an insulating material, and the upper surface of the second pressure block has a positioning post. The second electrode sheet and the second lithium niobate crystal sheet are both annular and sleeved on the positioning post. A positioning hole is provided in the center of the bottom surface of the mounting base, and the upper end of the positioning post is inserted into the positioning hole. This achieves precise positioning and stable installation of the force detection core, allowing the force signal to be accurately transmitted to the lithium niobate crystal sheet, enhancing the safety and stability of the sensor.

[0011] As a preferred implementation of a combined force and acceleration sensor, the upper surface of the upper push block is provided with a spherical bowl, which houses a top ball. The upper end of the top ball's outer surface contacts the bottom surface of the second pressure block. This ensures that the tightening force acts evenly and stably on the second pressure block and the force detection core, improving the stability and reliability of the force detection core.

[0012] As a preferred implementation of a combined force and acceleration sensor, the sensor housing includes a lower base having a positioning slot defined in its upper surface, into which the lower portion of the lower ejector block is positioned. This provides a stable mounting position for the lower ejector block, enhancing the stability and reliability of the jack assembly. This prevents inaccurate preload adjustment caused by deviations in the lower ejector block's movement, ensures the force detection core operates under accurate and stable preload, and improves the accuracy and stability of the sensor's force detection.

[0013] As a preferred implementation of a combined force and acceleration sensor, the sensor housing further comprises a left shell and a right shell. The left and right shells are joined to form a cylindrical or prismatic barrel, with the upper and lower bases respectively snapping onto the upper and lower ends of the barrel. The first threaded hole and the slotted hole are defined in the right shell, while the left shell is fitted with a dual-core connector for wiring. The split sensor housing design facilitates installation, removal, and maintenance of internal components, improving the overall performance and practicality of the sensor. It also facilitates connection to external devices, enhancing its applicability.

[0014] As a preferred implementation scheme for a force and acceleration composite sensor, the first rotational operating structure is a first bolt head located at the end of the tightening screw, and the second rotational operating structure is a second bolt head located at the end of the forward and reverse rotation screw; a first sealing gasket is provided between the first bolt head and the sensor housing, and the first sealing gasket covers the first threaded hole; a second sealing gasket is provided between the second bolt head and the sensor housing, and the second sealing gasket covers the long hole. The first and second bolt heads are used as rotational operating structures, which are easy to operate and facilitate pre-pressure adjustment by staff. At the same time, the bolts can be directly used as integral components; the provision of the first and second sealing gaskets effectively improves the protective performance of the sensor, prevents external environmental factors from damaging the internal components of the sensor, ensures that the sensor can operate stably and reliably even in harsh environments, extends the service life of the sensor, and also improves the detection accuracy and stability of the sensor.

[0015] On the other hand, the present invention also provides an adjustment method for the above-mentioned force and acceleration composite sensor, comprising: twisting a tightening screw to cause a first pressure block to press or loosen the acceleration detection core; when the first pressure block presses the acceleration detection core, close contact between the piezoelectric element, the mass block, and the base can be ensured, signal distortion or resonant frequency shift caused by looseness can be avoided, and the piezoelectric element can maintain a linear response under dynamic load, ensuring that the charge output within the range is proportional to the acceleration; when the first pressure block relaxes the acceleration detection core, the long-term mechanical fatigue of the piezoelectric element is reduced, and the influence of thermal stress is reduced;

[0016] And / or, by turning the screw forward and backward, the second pressure block can be pressed or loosened to the force detection core. When the second pressure block presses the force detection core, the pre-pressure increases, which can cause the piezoelectric element to bear additional stress in advance, the charge output to be saturated in advance, the actual measurable range to be reduced, and the upper limit of the sensor range to be saturated in advance; when the pre-pressure decreases, the sensor range increases.

[0017] The advantages of the present invention are as follows: Through an adjustable pressure block structure and threaded connection, this solution enables flexible adjustment of the preload of the acceleration and force detection components, preventing rebound, improving the stability and accuracy of the preload, and significantly enhancing the sensor's versatility. The jack assembly, based on a forward and reverse screw and connecting rod mechanism, enables precise and stable adjustment of the force detection core's preload, with flexible adjustment, force dispersion, and reduced risk of structural damage. The upper base provides a stable installation space and precise positioning reference for the acceleration detection assembly, ensuring accurate core installation and uniform preload, while also facilitating installation, disassembly, maintenance, and calibration. The annular component in the acceleration detection core ensures uniform force transmission, improving detection sensitivity and stability, while the insulating sleeve ensures proper operation and enhances structural reliability. The force detection core and related components work together to achieve precise positioning and stable installation, enhancing force detection accuracy and safety. The ball bowl and ball-tightening structure ensure uniform tightening force and enhance operational stability of the force detection core. The positioning grooves in the lower base enhance the stability of the jack assembly and ensure force detection accuracy. The split housing facilitates component installation and maintenance, protects internal components, optimizes the structural layout, and facilitates connection to external devices. The bolt head serves as a rotating operating mechanism for easy adjustment, and the sealing gasket enhances protection, ensuring stable operation in harsh environments, extending the sensor's service life, and improving detection accuracy. Furthermore, the sensor's adjustment method is simple and intuitive, enabling quick and precise adjustment of the sensor's range. Flexible preload adjustment allows the sensor to adapt to diverse working environments and measurement requirements, significantly improving its versatility and practicality, reducing operating costs, and improving work efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for the description. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a structural schematic diagram of a specific embodiment of the present invention.

[0020] Figure 2 It is an exploded schematic diagram of a specific embodiment of the present invention.

[0021] Figure 3 It is a structural schematic diagram of the jack assembly in a specific embodiment of the present invention.

[0022] Figure 4 Schematic diagram of the structure of the sensor housing in a specific embodiment of the present invention.

[0023] Figure 5 It is a structural schematic diagram of the upper seat body in a specific embodiment of the present invention.

[0024] Figure 6 It is a structural schematic diagram of the lower seat body in a specific embodiment of the present invention.

[0025] Figure 7 It is a structural schematic diagram of the right shell in a specific embodiment of the present invention.

[0026] Figure 8 Schematic diagram of the structure of the second pressing block in a specific embodiment of the present invention.

[0027] Description of main reference numerals

[0028] 01. Sensor housing, 01-1. First positioning surface, 01-2. Second positioning surface, 02. Acceleration detection core, 03. Force detection core, 1. Upper base, 1-1 Upper cover, 1-2. Mounting base, 1-3. Second threaded hole, 1-4. Mounting cavity, 1-5. Positioning hole, 2. Left housing, 3. First lithium niobate crystal plate, 4. First electrode plate, 5. Insulating sleeve, 6. Tightening screw, 6-1. First bolt head, 7. First pressure block, 8. Mass block, 9. Dual-core nozzle, 10. Lower base, 10-1 . Positioning groove, 11. Jack assembly, 11-1. Forward and reverse rotation screw, 11-2. Connecting block, 11-3. Connecting rod, 11-4. Upper top block, 11-5. Lower top block, 11-6. Ball bowl, 11-7. Second bolt head, 12. Second sealing gasket, 13. Top ball, 14. Second pressure block, 14-1. Positioning column, 15. Second electrode plate, 16. Second lithium niobate crystal plate, 17. First sealing gasket, 18. Right shell, 18-1. First threaded hole, 18-2. Long hole, 18-3. Limiting protrusion. DETAILED DESCRIPTION

[0029] In order to make the purpose, features, and advantages of the present invention more obvious and easy to understand, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in this specific embodiment. Obviously, the embodiments described below are only part of the embodiments of the present invention, not all of them. Based on the embodiments in this patent, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this patent.

[0030] Example 1

[0031] This embodiment provides a force and acceleration composite sensor, which includes a sensor housing 01, such as Figure 4 As shown, the sensor housing 01 is composed of four parts, including an upper base 1, a lower base 10, a left shell 2 and a right shell 18. The left shell 2 and the right shell 18 are connected to form a rectangular cylindrical structure that runs through the top and bottom (in other embodiments, it can also be a cylinder or a polygonal prism). The upper base 1 and the lower base 10 are respectively buckled at the upper and lower ends of the cylinder. Specifically, the lower surface of the upper base 1 and the upper surface of the lower base 10 are provided with positioning steps. The outer contour of the positioning steps is adapted to the inner cross-sectional shape of the cylindrical structure formed by the left shell 2 and the right shell 18. The positioning steps are embedded in the upper and lower ends of the cylindrical structure and welded and fixed. A double-core connector 9 for external wiring is installed on the left shell 2. Two copper needles are left at the center position of the double-core connector 9 for outputting acceleration signals and force signals respectively.

[0032] The acceleration detection component and force detection component are installed inside the sensor housing 01:

[0033] like Figure 1 、 2 As shown, the acceleration detection component includes an acceleration detection core 02, and the interior of the sensor housing 01 has a first positioning surface 01-1 and a first pressing block 7. In this embodiment, as shown in FIG. Figure 5 As shown, the upper seat body 1 includes an upper cover plate 1-1, and a mounting seat 1-2 is provided on the bottom surface of the upper cover plate 1-1. Figure 1 In the direction shown, a mounting cavity 1-4 is provided on one side of the mounting seat 1-2. The mounting cavity 1-4 is a cylindrical cavity. Figure 1 The left-right direction (lateral direction) is the depth direction of the installation cavity 1-4. In the depth direction of the installation cavity 1-4, the bottom surface of the installation cavity 1-4 is the first positioning surface 01-1. The acceleration detection core 02 and the first pressure block 7 are both located in the installation cavity 1-4. The acceleration detection core 02 is located between the first positioning surface 01-1 and the first pressure block 7. Figure 1 The direction shown is the reference, the center of the right end face of the first pressing block 7 is provided with a tightening screw 6, the center of the first positioning surface 01-1 is provided with a second threaded hole 1-3, the second threaded hole 1-3 is provided through the mounting seat 1-2, and at the same time Figure 1 、 7 As shown, a first threaded hole 18-1 is provided on the right side wall of the right shell 18, and the acceleration detection core 02 is a ring structure. The acceleration detection core 02 includes a first electrode piece 4, two first lithium niobate crystal pieces 3 and two mass blocks 8. The two first lithium niobate crystal pieces 3 are respectively located on both sides of the first electrode piece 4, and the mass block 8 is located on the side of the first lithium niobate crystal piece 3 facing away from the first electrode piece 4; the first electrode piece 4, the first lithium niobate crystal piece 3 and the mass block 8 are all annular, and an insulating sleeve 5 is provided on the tightening screw 6. The first electrode piece 4, the first lithium niobate crystal piece 3 and the mass block 8 are sleeved on the outer periphery of the insulating sleeve 5. After the right part of the tightening screw 6 passes through the acceleration detection core 02 and the insulating sleeve 5, it is connected to the second threaded hole 1-3 and the first threaded hole 1-3. The hole 18-1 is threadedly connected, and the right end of the tightening screw 6 is located outside the sensor housing 01, and is provided with a first rotation operating structure. In this embodiment, the first rotation operating structure is the first bolt head 6-1 located at the end of the tightening screw 6. Furthermore, the tightening screw 6 can directly use a bolt. When assembling the sensor, first assemble the upper base 1 and the right shell 18, and then screw the tightening screw 6 into the first threaded hole 18-1 and the second threaded hole 1-3 from left to right in turn and enter the installation cavity 1-4, and then put the insulating sleeve 5 and the acceleration detection core 02 on the tightening screw 6, and install the first pressure block 7 at the left end of the tightening screw 6 through threads (at this time, a threaded hole is opened in the center of the first pressure block 7, preferably a through threaded hole) and weld the first pressure block 7 to the tightening screw 6, and finally install the left shell 2.

[0034] The preload adjustment process of the acceleration detection core 02 is as follows: Figure 1 , turn the tightening screw 6, and under the action of the first threaded hole 18-1 and the second threaded hole 1-3, the tightening screw 6 drives the first pressure block 7 to move left and right. When the first pressure block 7 moves to the right, the pre-pressure increases, and in the opposite direction, it decreases. In terms of acceleration detection, when a vibration signal is generated on the surface of the sensor, the shear stress generated by the mass block 8 will directly act on the first lithium niobate crystal piece 3, causing the first electrode piece 4 to generate an electric charge, thereby outputting an electrical signal, thereby simultaneously realizing the monitoring of the acceleration signal. In the acceleration detection component, the pre-pressure is used to change the initial stress state of the first lithium niobate crystal piece 3 and the first electrode piece 4, and then adjust the frequency response and linearity within the appropriate range. When the pre-pressure increases, the rigidity is enhanced, which is suitable for measuring high-amplitude dynamic loads; when the pre-pressure decreases, the sensor is more sensitive to small pressure changes and can be used for low-load measurement.

[0035] The force detection component includes a force detection core 03, and the interior of the sensor housing 01 also has a second positioning surface 01-2 and a second pressure block 14. The force detection core 03 is located between the second positioning surface 01-2 and the second pressure block 14. In this embodiment, it can be seen from the above that the mounting seat 1-2 is located inside the sensor housing, and the bottom surface of the mounting seat 1-2 is set as the second positioning surface 01-2. The force detection core 03 is located below the mounting seat 1-2, and the second pressure block 14 is located below the force detection core 03 and presses the force detection core 03 upward. Specifically, the force detection core 03 includes The mounting base 1-2 includes two second electrode sheets 15 and two second lithium niobate crystal sheets 16, which are stacked at intervals, and the second electrode sheet 15 is located at the bottom layer and contacts the second pressing block 14; the second pressing block 14 is made of insulating material, and the upper surface of the second pressing block 14 has a positioning column 14-1, the second electrode sheet 15 and the second lithium niobate crystal sheet 16 are both annular and are sleeved on the positioning column 14-1, and a positioning hole 1-5 is opened in the center of the bottom surface of the mounting base 1-2, and the upper end of the positioning column 14-1 is inserted into the positioning hole 1-5.

[0036] A jack assembly 11 is provided on the side of the second pressing block 14 facing away from the force detection core 03 (i.e., the bottom surface of the second pressing block 14). Figure 3As shown, the jack assembly 11 includes a forward and reverse rotating screw 11-1, which has two sections of threads with opposite rotation directions in the length direction. Connecting blocks 11-2 are respectively installed on the two sections of threads of the forward and reverse rotating screw 11-1 through threads. It can be seen that when the forward and reverse rotating screw 11-1 rotates, the two connecting blocks 11-2 will move synchronously relative to or opposite to each other. Two connecting rods 11-3 are hingedly installed on each of the connecting blocks 11-2 and are respectively located on the upper and lower sides of the forward and reverse rotating screw 11-1. The two connecting rods 11-3 located above the forward and reverse rotating screw 11-1 are jointly hingedly installed with an upper top block 11-4, and the two connecting rods 11-3 located below the forward and reverse rotating screw 11-1 are jointly hingedly installed with a lower top block 11-5. The four connecting rods 11-3 form a rhombus, and the two connecting blocks 11-2, the upper top block 11-4 and the lower top block 11-5 are respectively located at the four vertices of the rhombus.

[0037] The upper block 11-4 conflicts with the second pressing block 14. Figure 3 The upper surface of the upper top block 11-4 is provided with a ball bowl 11-6, and the ball bowl 11-6 is provided with a top ball 13. The upper end of the outer surface of the top ball 13 contacts the bottom surface of the second pressing block 14; the lower top block 11-5 contacts the lower seat body 10, referring to Figure 2 、 6 The upper surface of the lower base 10 is provided with a positioning groove 10-1, and the lower portion of the lower ejector block 11-5 is located in the positioning groove 10-1. The right shell 18 of the sensor housing 01 also has a long hole 18-2. The right end of the forward and reverse rotation screw 11-1 serves as the operating end of the jack assembly 11. This end passes through the long hole 18-2 and is located outside the sensor housing 01. This end is provided with a second rotation operating structure, which is a second bolt head 11-7 located at the end of the forward and reverse rotation screw 11-1.

[0038] The preload adjustment process of the force detection core 03 is as follows: by turning the screw 11-1 forward and backward, the upper block 11-4 will rise and fall slightly. When the upper block 11-4 rises, the preload increases, and vice versa. In terms of force detection, threaded holes are respectively provided on the upper surface of the upper seat 1 and the lower surface of the lower seat 10, which are installed in the use position through the threaded holes. When tension or pressure is generated between the upper seat 1 and the lower seat 10, it is transmitted to the force detection core 03 through the jack assembly 11. Due to the compression effect of the second lithium niobate crystal sheet 16, a piezoelectric signal is output through the second electrode sheet 15, thereby realizing force signal monitoring. In order to prevent the left connecting block 11-2 from detaching from the forward and reverse rotation screw 11-1 during the descent of the jack assembly 11, a limiting protrusion 18-3 protruding to the left is provided on the inner bottom of the right shell 18. When the right connecting block 11-2 moves to the right limit position, it abuts against the limiting protrusion 18-3. At this time, the left connecting block 11-2 is restricted to the left limit position on the forward and reverse rotation screw 11-1.

[0039] The overall assembly process of this sensor is:

[0040] Splice the right shell 18 and the lower base 10 and weld them together at the joint;

[0041] Install the jack assembly 11 on the lower base 10, insert the right end of the forward and reverse screw 11-1 through the long hole 18-2, install a nut and weld it to form the second bolt head 11-7;

[0042] Place the top ball 13 in the ball bowl 11-6 on the top surface of the upper top block 11-4, and place the stacked second pressing block 14 and the force detection core 03 on top. Weld a signal line for signal output to the second electrode sheet 15 between the two second lithium niobate crystal sheets 16. Weld a wire to the bottom second electrode sheet 15 and connect it to the sensor housing 01 for grounding.

[0043] Then, install the upper body 1 and the acceleration detection assembly in the same manner as described above, and weld the signal wires to the first electrode sheet 4;

[0044] Finally, the left shell 2 is installed, the signal line is connected to the copper core of the double-core connector 9, and the left shell 2 is welded to the upper base 1, the lower base 10 and the right shell 18 along the joint seam.

[0045] Furthermore, in order to improve the sealing performance of the composite sensor, a first sealing gasket 17 is provided between the first bolt head 6-1 and the sensor housing 01, and the first sealing gasket 17 covers the first threaded hole 18-1. A second sealing gasket 12 is provided between the second bolt head 11-7 and the sensor housing 01, and the second sealing gasket 12 covers the long hole 18-2. The first sealing gasket 17 and the second sealing gasket 12 are made of phosphor bronze.

[0046] Example 2

[0047] Based on the composite sensor structure of the first embodiment, this embodiment further provides a method for adjusting a force and acceleration composite sensor, including:

[0048] Tightening screw 6 causes first pressing block 7 to compress or loosen acceleration detection core 02, thereby adjusting frequency response and linearity within a suitable range. When first pressing block 7 compresses acceleration detection core 02, close contact between the piezoelectric element, mass block 8, and base can be ensured, avoiding signal distortion or resonant frequency shift caused by looseness. Appropriate preload can enable the piezoelectric element to maintain a linear response under dynamic load, ensuring that the charge output within the range is proportional to the acceleration. When first pressing block 7 loosens acceleration detection core 02, long-term mechanical fatigue of the piezoelectric element is reduced, and the influence of thermal stress is reduced.

[0049] And / or, by turning the forward and reverse screw 11-1, the second pressure block 14 presses or relaxes the force detection core 03. When the second pressure block 14 presses the force detection core 03, the pre-pressure increases, which can cause the piezoelectric element to bear additional stress in advance, the charge output is saturated in advance, the actual measurable range is reduced, and the upper limit of the sensor range is saturated in advance; when the second pressure block 14 relaxes the force detection core 03, the pre-pressure decreases, and the sensor range increases.

[0050] The user can adjust the pressing force of the force detection core 03 or the acceleration detection core 02 individually or simultaneously as needed.

[0051] The above embodiments demonstrate the beneficial effects of the present invention. Through its adjustable pressure block structure and threaded connection, the present solution enables flexible adjustment of the preload of the acceleration and force detection assemblies, preventing rebound and improving the stability and accuracy of the preload, significantly enhancing the sensor's versatility. The jack assembly, based on a forward and reverse screw and connecting rod mechanism, enables precise and stable adjustment of the force detection core's preload, offering flexible adjustment, force dispersion, and reduced risk of structural damage. The upper base provides a stable installation space and precise positioning reference for the acceleration detection assembly, ensuring accurate core installation and uniform preload, while also facilitating installation, disassembly, maintenance, and calibration. The annular component within the acceleration detection core ensures uniform force transmission, enhancing detection sensitivity and stability, while the insulating sleeve ensures proper operation and enhances structural reliability. The force detection core and related components work together to achieve precise positioning and stable installation, improving force detection accuracy and safety. The ball bowl and top ball structure ensure uniform tightening force, enhancing operational stability of the force detection core. The positioning grooves in the lower base enhance the stability of the jack assembly and ensure force detection accuracy. The split housing facilitates component installation and maintenance, protects internal components, optimizes the structural layout, and facilitates connection to external devices. The bolt head serves as a rotating operating mechanism for easy adjustment, and the sealing gasket enhances protection, ensuring stable operation in harsh environments, extending the sensor's service life, and improving detection accuracy. Furthermore, the sensor's adjustment method is simple and intuitive, enabling quick and precise adjustment of the sensor's range. Flexible preload adjustment allows the sensor to adapt to diverse working environments and measurement requirements, significantly improving its versatility and practicality, reducing operating costs, and improving work efficiency.

[0052] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A force and acceleration composite sensor, comprising a sensor housing (01), wherein an acceleration detection component and a force detection component are installed inside the sensor housing (01), characterized in that: The acceleration detection assembly includes an acceleration detection core (02), a first positioning surface (01-1) and a first pressing block (7) are provided inside the sensor housing (01), the acceleration detection core (02) is located between the first positioning surface (01-1) and the first pressing block (7), a tightening screw (6) is fixedly provided on the first pressing block (7), the sensor housing (01) has a first threaded hole (18-1), the tightening screw (6) passes through the acceleration detection core (02) and is threadedly connected to the first threaded hole (18-1) of the sensor housing (01), and a first rotation operation is provided at one end of the tightening screw (6) located outside the sensor housing (01). Structure; the acceleration detection core (02) includes a first electrode sheet (4), two first lithium niobate crystal sheets (3) and two mass blocks (8), the two first lithium niobate crystal sheets (3) are respectively located on both sides of the first electrode sheet (4), the mass block (8) is located on the side of the first lithium niobate crystal sheet (3) facing away from the first electrode sheet (4), the first electrode sheet (4), the first lithium niobate crystal sheet (3) and the mass block (8) are all annular, the tightening screw (6) is provided with an insulating sleeve (5), and the first electrode sheet (4), the first lithium niobate crystal sheet (3) and the mass block (8) are sleeved on the outer periphery of the insulating sleeve (5); The force detection assembly includes a force detection core (03), and the interior of the sensor housing (01) further includes a second positioning surface (01-2) and a second pressure block (14). The force detection core (03) is located between the second positioning surface (01-2) and the second pressure block (14). A jack assembly (11) is provided on a side of the second pressure block (14) facing away from the force detection core (03). The operating end of the jack assembly (11) is located outside the sensor housing (01). The sensor housing (01) includes an upper seat (1), and the upper seat (1) includes an upper cover (1-1). The bottom surface of the upper cover (1-1) is provided with a mounting seat (1-2). The bottom surface of the mounting seat (1-2) is a plane and serves as the second positioning surface ( 01-2), the force detection core (03) includes two second electrode sheets (15) and two second lithium niobate crystal sheets (16), the two second electrode sheets (15) and the two second lithium niobate crystal sheets (16) are stacked at intervals, the second electrode sheet (15) is located at the bottom layer and contacts the second pressing block (14), the second pressing block (14) is made of insulating material, the upper surface of the second pressing block (14) has a positioning column (14-1), the second electrode sheet (15) and the second lithium niobate crystal sheet (16) are both annular and are sleeved on the positioning column (14-1), a positioning hole (1-5) is opened at the center of the bottom surface of the mounting seat (1-2), and the upper end of the positioning column (14-1) is inserted into the positioning hole (1-5).

2. The force and acceleration composite sensor according to claim 1, characterized in that: The jack assembly (11) comprises a forward and reverse rotating screw (11-1), and connecting blocks (11-2) are respectively installed on the two threads of the forward and reverse rotating screw (11-1) through threads. Two connecting rods (11-3) are hingedly installed on each connecting block (11-2) and are respectively located on the upper and lower sides of the forward and reverse rotating screw (11-1). The two connecting rods (11-3) located above the forward and reverse rotating screw (11-1) are jointly hingedly installed with an upper block (11-4), which is located on the forward and reverse rotating screw (11-1). 1) The two lower connecting rods (11-3) are hingedly mounted with a lower top block (11-5), the upper top block (11-4) contacts the second pressure block (14), and the lower top block (11-5) contacts the inner wall of the sensor housing (01). The outer wall of the sensor housing (01) is provided with a long hole (18-2), one end of the forward and reverse rotation screw (11-1) passes through the long hole (18-2) and is located outside the sensor housing (01), and the end is provided with a second rotation operation structure.

3. The force and acceleration composite sensor according to claim 2, characterized in that: A mounting cavity (1-4) is provided on one side of the mounting seat (1-2); in the depth direction of the mounting cavity (1-4), the bottom surface of the mounting cavity (1-4) is the first positioning surface (01-1) and is provided with a second threaded hole (1-3); the acceleration detection core (02) and the first pressing block (7) are both located in the mounting cavity (1-4); the tightening screw (6) passes through the second threaded hole (1-3) and is threadably engaged with the second threaded hole (1-3).

4. The force and acceleration composite sensor according to claim 1, characterized in that: A ball bowl (11-6) is provided on the upper surface of the upper top block (11-4), a top ball (13) is provided in the ball bowl (11-6), and the upper end of the outer surface of the top ball (13) contacts the bottom surface of the second pressing block (14).

5. The force and acceleration composite sensor according to claim 3, characterized in that: The sensor housing (01) comprises a lower seat body (10), a positioning groove (10-1) is provided on the upper surface of the lower seat body (10), and the lower part of the lower top block (11-5) is located in the positioning groove (10-1).

6. The force and acceleration composite sensor according to claim 5, characterized in that: The sensor housing (01) further comprises a left shell (2) and a right shell (18), wherein the left shell (2) and the right shell (18) are butted together to form a cylindrical or prismatic barrel, and the upper seat (1) and the lower seat (10) are respectively engaged with the upper and lower ends of the barrel; the first threaded hole (18-1) and the long hole (18-2) are provided on the right shell (18), and a double-core connector (9) for wiring is installed on the left shell (2).

7. The force and acceleration composite sensor according to claim 2, characterized in that: The first rotation operation structure is a first bolt head (6-1) located at the end of the tightening screw (6), and the second rotation operation structure is a second bolt head (11-7) located at the end of the forward and reverse rotation screw (11-1); a first sealing gasket (17) is provided between the first bolt head (6-1) and the sensor housing (01), and the first sealing gasket (17) covers the first threaded hole (18-1); a second sealing gasket (12) is provided between the second bolt head (11-7) and the sensor housing (01), and the second sealing gasket (12) covers the long hole (18-2).

8. A method for adjusting the force and acceleration composite sensor according to any one of claims 1 to 7, characterized in that: include: The tightening screw (6) is twisted to make the first pressing block (7) press or loosen the acceleration detection core (02). When the first pressing block (7) presses the acceleration detection core (02), close contact between the piezoelectric element, the mass block (8), and the base can be ensured, thereby avoiding signal distortion or resonance frequency shift caused by looseness. Appropriate pre-pressure can enable the piezoelectric element to maintain a linear response under dynamic load, ensuring that the charge output within the range is proportional to the acceleration. When the first pressing block (7) loosens the acceleration detection core (02), the long-term mechanical fatigue of the piezoelectric element is reduced, and the influence of thermal stress is reduced. And / or, the forward and reverse rotation screw (11-1) is turned to make the second pressing block (14) press or release the force detection core (03); when the second pressing block (14) presses the force detection core (03), the pre-pressure is increased, so that the piezoelectric element can bear the additional stress in advance, the charge output is saturated in advance, the actual measurable range is reduced, and the upper limit of the sensor range is saturated in advance; when the second pressing block (14) releases the force detection core (03), the pre-pressure is reduced and the sensor range is increased.

Images