Structure self-decoupling four-point layout three-dimensional force piezoelectric sensor

Abstract

The invention provides a structure self-decoupling four-point layout three-dimensional force piezoelectric sensor, which comprises an upper pressing plate, an outer sleeve, a piezoelectric material, a lower pressing plate and a radio frequency adapter, and is characterized in that the upper pressing plate, the outer sleeve and the lower pressing plate define an accommodating space, the piezoelectric material is arranged in the accommodating space, the radio frequency adapter penetrates through the outer sleeve, and the radio frequency adapter is arranged in the accommodating space. The sensor is used for transmitting an electric signal generated by the piezoelectric material to external electronic equipment or a measuring instrument; the piezoelectric material is four combined quartz plates which are uniformly arranged on the accommodating space and have different output polarities, each combined quartz plate comprises five electrode plates and six quartz plates which are respectively stacked at intervals, when the piezoelectric material is stressed, the electrode plates in the stress axis direction output negative charges, and the charges in other axis directions are mutually counteracted, so that structural decoupling is realized, and the output polarity of the piezoelectric material is different. The invention provides the four-point layout three-dimensional force piezoelectric sensor which is high in sensitivity, high in precision and reliable in signal transmission.

Description

Technical Field

[0001] The present invention relates to the field of sensor technology, and in particular to a four-point layout three-dimensional force piezoelectric sensor with a self-decoupling structure. Background Art

[0002] In modern industry and scientific research, accurate measurement of multi-dimensional forces and torques is a key requirement, especially in the fields of robotics, aerospace, automotive engineering, and biomedicine. Traditional single-axis force sensors can only measure forces in one direction and cannot meet the needs of multi-dimensional force measurement under complex working conditions. Therefore, the development of multi-dimensional force sensors has become an important research direction.

[0003] At present, multi-dimensional force piezoelectric sensors usually use a single group of crystals, usually a quartz sheet that is processed and formed in one piece. However, this method has the following defects and shortcomings: large-sized quartz crystals take longer to grow, and the crystal structure is prone to change and distortion during the process, resulting in a decrease in crystal quality or surface defects, and the growth cycle is long and the cost is high; the whole quartz sheet needs to be cut from a large piece of quartz raw material, which is limited in size and difficult to manufacture oversized quartz sheets; one-piece molding requires the use of larger quartz raw materials, and large-sized quartz sheets are more prone to cracks and defects, resulting in higher manufacturing costs; special packaging and handling are required during transportation, and the transportation cost is relatively high.

[0004] However, piezoelectric sensors composed of multiple crystals have some problems, such as complex structure, difficulty in signal decoupling, and low measurement accuracy. Especially in multi-dimensional force measurement, forces and torques in different directions are coupled with each other, resulting in inaccurate measurement results.

[0005] Therefore, it is necessary to improve the prior art. Summary of the invention

[0006] The piezoelectric sensors composed of multiple groups of crystals in the prior art have problems such as complex structure, difficulty in signal decoupling or low measurement accuracy. Therefore, the present invention provides a four-point layout three-dimensional force piezoelectric sensor with self-decoupling structure to solve the above problems.

[0007] The present invention provides a structural self-decoupling four-point layout three-dimensional force piezoelectric sensor, which comprises an upper pressing plate, an outer sleeve, a piezoelectric material, a lower pressing plate and a radio frequency adapter, wherein the upper pressing plate, the outer sleeve and the lower pressing plate enclose a receiving space, the piezoelectric material is arranged in the receiving space, and the radio frequency adapter is arranged through the outer sleeve, and is used to transmit the electrical signal generated by the piezoelectric material to an external electronic device or a measuring instrument; the piezoelectric material is four combined quartz plates evenly arranged on the receiving space and having different output polarities, each combined quartz plate comprises five electrode plates and six quartz plates which are stacked at intervals, wherein the five electrode plates comprise two grounding electrode plates, an X-direction electrode plate, a Y-direction electrode plate and a Z-direction electrode plate, and the six quartz plates respectively comprise two X-direction quartz plates, two Y-direction quartz plates and two Z-direction quartz plates, when subjected to force, the electrode plates in the direction of the force axis output negative charges, and the charges in the other axis directions cancel each other out, thereby achieving structural decoupling.

[0008] In one implementation, the combined quartz plate includes, from top to bottom, a first X-direction quartz plate, an X-direction electrode plate, a second X-direction quartz plate, a first grounding electrode plate, a first Y-direction quartz plate, a Y-direction electrode plate, a second Y-direction quartz plate, a second grounding electrode plate, a first Z-direction quartz plate, a Z-direction electrode plate, and a second Z-direction quartz plate.

[0009] In one implementation, the four combined quartz plates include a first combined quartz plate, a second combined quartz plate, a third combined quartz plate and a fourth combined quartz plate which are evenly spaced in a clockwise direction. When subjected to force, the X-direction electrode plate, the Y-direction electrode plate and the Z-direction electrode plate of the first combined quartz plate all output negative charges; the X-direction electrode plate of the second combined quartz plate outputs positive charges, and the Y-direction electrode plate and the Z-direction electrode plate thereof output negative charges; the X-direction electrode plate and the Y-direction electrode plate of the third combined quartz plate output positive charges, and the Z-direction electrode plate thereof outputs negative charges; the Y-direction electrode plate of the fourth combined quartz plate outputs positive charges, and the X-direction electrode plate and the Z-direction electrode plate thereof output negative charges.

[0010] In one implementation, the four-point layout three-dimensional force piezoelectric sensor further includes an upper cover plate and a lower cover plate, wherein the upper cover plate is disposed between the upper pressure plate and the piezoelectric material, and the lower cover plate is disposed between the piezoelectric material and the lower pressure plate.

[0011] In one implementation, the upper pressure plate, the upper cover plate and the lower cover plate are annular structures, and the four-point layout three-dimensional force piezoelectric sensor also includes connecting screws, which sequentially connect the upper pressure plate, the upper cover plate, the lower cover plate and the lower pressure plate.

[0012] In one implementation, the number of the connecting screws is eight, four of which are used to fix the piezoelectric material, and the remaining four connecting screws are respectively disposed between two adjacent piezoelectric materials.

[0013] In one implementation, the four-point layout three-dimensional force piezoelectric sensor also includes a screw sleeve that is arranged in cooperation with the connecting screw, the screw sleeve is fixedly arranged in the receiving space, and the combined quartz plate is sleeved on the screw sleeve.

[0014] In one implementation, the number of the radio frequency adapters is three, and the three radio frequency adapters are all arranged on the outer surface of the outer sleeve.

[0015] Beneficial effects: The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor provided by the present invention is made into a four-point layout multi-dimensional force sensor by providing four groups of combined quartz plates with different polarities, so as to obtain a structural self-decoupling three-dimensional force piezoelectric sensor, which reduces external interference, enables the sensor to maintain stable performance during long-term operation, and improves the accuracy and reliability of the sensor; compared with a single group of combined quartz piezoelectric sensors, the piezoelectric sensor composed of four groups of combined quartz plates provided by the present invention has a smaller size and is easier to process when making a large-size piezoelectric sensor, and has a lower cost; the contact area of ​​a single quartz group of the four groups of combined quartz plates becomes smaller, the yield strength of the four groups of combined quartz will be higher, and the plane error will be smaller; smaller quartz raw materials can make the sensor size larger, shorten the quartz crystal cultivation time, and reduce costs; the present invention provides a structural self-decoupling four-point layout three-dimensional force piezoelectric sensor, which realizes independent measurement of multi-dimensional force and structural self-decoupling, has the advantages of high sensitivity, high precision, reliable signal transmission, good mechanical stability, etc., and is suitable for various application scenarios that require precise measurement of multi-dimensional force, such as industrial robots, precision instruments, aerospace and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the overall structure of the four-point layout three-dimensional force piezoelectric sensor with structural self-decoupling provided by the present invention; Figure 2 yes Figure 1 The schematic diagram of the decomposed structure of the four-point layout three-dimensional force piezoelectric sensor with self-decoupling structure shown; Figure 3 yes Figure 1 The cross-sectional structure diagram of the self-decoupling four-point layout three-dimensional force piezoelectric sensor shown; Figure 4 yes Figure 1 The shown structure is a partial structural schematic diagram of a four-point layout three-dimensional force piezoelectric sensor with self-decoupling.

[0017] The numbers in the figure are as follows: 10. Upper pressure plate; 20. Upper cover plate; 30. Outer sleeve; 40. Piezoelectric material; 41. First combined quartz plate; 42. Second combined quartz plate; 43. Third combined quartz plate; 44. Fourth combined quartz plate; 401. First X-direction quartz plate; 402. X-direction electrode plate; 403. Second X-direction quartz plate; 404. First grounding electrode plate; 405. First Y-direction quartz plate; 406. Y-direction electrode plate; 407. Second Y-direction quartz plate; 408. Second grounding electrode plate; 409. First Z-direction quartz plate; 410. Z-direction electrode plate; 411. Second Z-direction quartz plate; 50. Lower cover plate; 60. Lower pressure plate; 70. RF adapter; 80. Connecting screws; 90. Screw sleeve.

[0018] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0019] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0020] Those skilled in the art will appreciate that, unless expressly stated otherwise, the singular forms "a", "an", "said", "above", and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present invention refers to the presence of the features, integers, steps, operations, elements, units, modules, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, units, modules, components, and / or groups thereof. It should be understood that when we refer to an element as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intermediate elements. In addition, the "connection" or "coupling" used herein may include wireless connection or wireless coupling. The term "and / or" used herein includes all or any unit and all combinations of one or more associated listed items.

[0021] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the field to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless specifically defined as here.

[0022] Combined with reference Figure 1-Figure 4 , Figure 1 It is a schematic diagram of the overall structure of the four-point layout three-dimensional force piezoelectric sensor with self-decoupling structure provided by the present invention. Figure 2 yes Figure 1 The schematic diagram of the decomposed structure of the self-decoupled four-point layout three-dimensional force piezoelectric sensor shown in the figure. Figure 3 yes Figure 1 The cross-sectional structure diagram of the self-decoupling four-point layout three-dimensional force piezoelectric sensor shown in the figure. Figure 4 yes Figure 1 The shown structure is a partial structural schematic diagram of a four-point layout three-dimensional force piezoelectric sensor with self-decoupling.

[0023] The present invention provides a four-point layout three-dimensional force piezoelectric sensor with a self-decoupling structure, which includes an upper pressing plate 10, an upper cover plate 20, an outer sleeve 30, a piezoelectric material 40, a lower cover plate 50, a lower pressing plate 60 and a radio frequency adapter 70. The upper pressing plate 10, the outer sleeve 30 and the lower pressing plate 50 enclose a receiving space, the piezoelectric material 50 is arranged in the receiving space, and the radio frequency adapter 70 is arranged through the outer sleeve 30, and is used to transmit the electrical signal generated by the piezoelectric material 40 to an external electronic device or measuring instrument; the upper cover plate 20 is arranged between the upper pressing plate 10 and the piezoelectric material 40, and the lower cover plate 50 is arranged between the piezoelectric material 40 and the lower pressing plate 60. The upper pressing plate 10 is used to apply a preload and is provided with a mounting hole. The piezoelectric material 40 is used to sense mechanical stress and generate electric charge. The receiving space can effectively protect the internal piezoelectric material 40 and ensure the mechanical strength and stability of the sensor. The upper cover plate 20 and the lower cover plate 50 provide additional mechanical protection and help distribute the stress applied to the piezoelectric material 40 .

[0024] Further, the piezoelectric material 40 is four combined quartz plates evenly arranged on the receiving space and having different output polarities, each combined quartz plate includes five electrode plates and six quartz plates stacked at intervals, wherein the five electrode plates include two grounding electrode plates, one X-direction electrode plate, one Y-direction electrode plate and one Z-direction electrode plate, and the six quartz plates include two X-direction quartz plates, two Y-direction quartz plates and two Z-direction quartz plates, respectively. When subjected to force, the electrode plates in the direction of the force axis output negative charges, and the charges in the other axis directions cancel each other out, thereby achieving structural decoupling. In the present invention, by setting different combined quartz plates to output charges of different polarities, the decoupling of forces in each direction can be achieved through polarity differences.

[0025] Specifically, the combined quartz plate includes, from top to bottom, a first X-direction quartz plate 401, an X-direction electrode plate 402, a second X-direction quartz plate 403, a first grounding electrode plate 404, a first Y-direction quartz plate 405, a Y-direction electrode plate 406, a second Y-direction quartz plate 407, a second grounding electrode plate 408, a first Z-direction quartz plate 409, a Z-direction electrode plate 410, and a second Z-direction quartz plate 411. By arranging the X, Y, and Z-direction quartz plates and electrode plates from top to bottom, independent measurement of forces in different directions is ensured. At the same time, by adjusting the polarity setting of the electrode plates, effective decoupling of forces can be achieved to ensure the accuracy of the measurement results.

[0026] Specifically, the four combined quartz plates include a first combined quartz plate 41, a second combined quartz plate 42, a third combined quartz plate 43 and a fourth combined quartz plate 44 which are evenly spaced in a clockwise direction. When subjected to force, the X-direction electrode plate, the Y-direction electrode plate and the Z-direction electrode plate of the first combined quartz plate 41 all output negative charges; the X-direction electrode plate of the second combined quartz plate 42 outputs positive charges, and the Y-direction electrode plate and the Z-direction electrode plate thereof output negative charges; the X-direction electrode plate and the Y-direction electrode plate of the third combined quartz plate 43 output positive charges, and the Z-direction electrode plate thereof outputs negative charges; the Y-direction electrode plate of the fourth combined quartz plate 44 outputs positive charges, and the X-direction electrode plate and the Z-direction electrode plate thereof output negative charges.

[0027] Specifically, the upper pressure plate 10, the upper cover plate 20 and the lower cover plate 50 are annular structures, and the four-point layout three-dimensional force piezoelectric sensor also includes connecting screws 80, and the connecting screws 80 connect the upper pressure plate 10, the upper cover plate 20, the lower cover plate 50 and the lower pressure plate 60 in sequence.

[0028] Specifically, the number of the connecting screws 80 is eight, of which four connecting screws 80 are used to fix the piezoelectric material, and the remaining four connecting screws 80 are respectively arranged between two adjacent piezoelectric materials 40. Furthermore, the four-point layout three-dimensional force piezoelectric sensor also includes a screw sleeve 90 arranged in cooperation with the connecting screw 80, the screw sleeve 90 is fixedly arranged in the receiving space, and the combined quartz plate is sleeved on the screw sleeve 90. The connecting screws 80 and the screw sleeve 90 ensure a reliable connection between the components, further fix the piezoelectric material 40, avoid displacement caused by the action of force, and reduce measurement errors caused by mechanical vibration or impact.

[0029] Specifically, the number of the RF adapters 70 is three, and the three RF adapters 70 are all arranged on the outer surface of the outer sleeve.

[0030] The working principle of the self-decoupling four-point layout three-dimensional force piezoelectric sensor in the structure is as follows: When the force is applied in the Z direction: The quartz plates in the Z direction of the first combined quartz plate 41, the second combined quartz plate 42, the third combined quartz plate 43 and the fourth combined quartz plate 44 are simultaneously subjected to pressure, and the Z axis outputs negative charges; The quartz plates in the X direction of the first combined quartz plate 41 and the fourth combined quartz plate 44 are subjected to pressure to generate negative charges, and the second combined quartz plate 42 and the third combined quartz plate 43 are subjected to pressure to generate positive charges, and the two charges cancel each other out, achieving structural decoupling, and no output on the X axis; The quartz plates in the Y direction of the first and second combined quartz plates 41 and 42 are subjected to pressure to generate negative charges, and the third and fourth combined quartz plates 43 and 44 are subjected to pressure to generate positive charges, and the two charges cancel each other out, resulting in no output on the Y axis.

[0031] When force is applied in the X direction: The first combined quartz plate 41 and the fourth combined quartz plate 44 are subjected to pressure in the Z direction to generate negative charges, and the second combined quartz plate 42 and the third combined quartz plate 43 are subjected to tension to generate positive charges. The two charges cancel each other out, achieving structural decoupling, and no output in the Z axis; The first combined quartz plate 41 and the fourth combined quartz plate 44 are subjected to pressure in the X direction to generate negative charges, and the second combined quartz plate 42 and the third combined quartz plate 43 are subjected to tension to generate positive loads, and the X axis outputs negative charges; The first and fourth quartz plates 41 and 44 are subjected to pressure in the Y direction, one positive and one negative, which cancel each other out. The second and third quartz plates 42 and 43 are subjected to tension, one positive and one negative, which cancel each other out, thus achieving structural decoupling and no output on the Y axis.

[0032] When the force is applied in the Y direction: The first combined quartz plate 41 and the second combined quartz plate 42 are subjected to pressure in the Z direction to generate negative charges, and the third combined quartz plate 43 and the fourth combined quartz plate 44 are subjected to tension to generate positive charges. The two charges cancel each other out, achieving structural decoupling, and no output in the Z axis; When the first and second quartz plates 41 and 42 are compressed in the X direction, the positive and negative cancel each other out. When the third and fourth quartz plates 43 and 44 are pulled, the positive and negative cancel each other out, thus achieving structural decoupling and no output in the X axis.

[0033] The first and second quartz plates 41 and 42 are subjected to pressure in the Y direction to generate negative charges, and the third and fourth quartz plates 43 and 44 are subjected to tension to generate positive loads, and the Y axis outputs negative charges.

[0034] The present invention provides four groups of combined quartz plates evenly distributed and installed on a circular fixed plate to obtain a four-point layout three-dimensional force piezoelectric sensor with structural self-decoupling. The structural self-decoupling reduces external interference, so that the sensor can maintain stable performance during long-term operation; relative to a single group of combined quartz piezoelectric sensors, the four groups of combined quartz piezoelectric sensors provided by the present invention are smaller and easier to process than a single group when making large-size piezoelectric sensors, and the cost is lower; under the same conditions of the original flatness and load in contact with the quartz plate, due to the increase in area, the greater the error in flatness, the smaller the contact area of ​​a single quartz group of the four groups of combined quartz relative to the single group of combined quartz, and the yield strength of the four groups of combined quartz will be higher; the sensor size can be made larger with smaller quartz raw materials, shortening the quartz crystal cultivation time. The present invention provides a four-point layout three-dimensional force piezoelectric sensor with structural self-decoupling, which realizes independent measurement of multi-dimensional force and structural self-decoupling, has the advantages of high sensitivity, high precision, reliable signal transmission, good mechanical stability, etc., and is suitable for various application scenarios that require accurate measurement of multi-dimensional force, such as industrial robots, precision instruments, aerospace and other fields.

[0035] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A four-point layout three-dimensional force piezoelectric sensor with self-decoupling structure, characterized in that: It includes an upper pressing plate, an outer sleeve, a piezoelectric material, a lower pressing plate and a radio frequency adapter, wherein the upper pressing plate, the outer sleeve and the lower pressing plate form a receiving space, the piezoelectric material is arranged in the receiving space, and the radio frequency adapter is arranged through the outer sleeve, and is used to transmit the electrical signal generated by the piezoelectric material to an external electronic device or a measuring instrument; The piezoelectric material is four combined quartz plates that are evenly arranged on the receiving space and have different output polarities. Each combined quartz plate includes five electrode plates and six quartz plates that are stacked at intervals. The five electrode plates include two grounding electrode plates, an X-direction electrode plate, a Y-direction electrode plate and a Z-direction electrode plate. The six quartz plates include two X-direction quartz plates, two Y-direction quartz plates and two Z-direction quartz plates. When subjected to force, the electrode plates in the direction of the force axis output negative charges, and the charges in the other axis directions cancel each other out, thereby achieving structural decoupling.

2. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 1 is characterized in that: The combined quartz plate includes, from top to bottom, a first X-direction quartz plate, an X-direction electrode plate, a second X-direction quartz plate, a first grounding electrode plate, a first Y-direction quartz plate, a Y-direction electrode plate, a second Y-direction quartz plate, a second grounding electrode plate, a first Z-direction quartz plate, a Z-direction electrode plate, and a second Z-direction quartz plate.

3. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 1 is characterized in that: The four combined quartz plates include a first combined quartz plate, a second combined quartz plate, a third combined quartz plate and a fourth combined quartz plate which are evenly spaced in a clockwise direction. When subjected to force, the X-direction electrode plate, the Y-direction electrode plate and the Z-direction electrode plate of the first combined quartz plate all output negative charges; the X-direction electrode plate of the second combined quartz plate outputs positive charges, and the Y-direction electrode plate and the Z-direction electrode plate thereof output negative charges; the X-direction electrode plate and the Y-direction electrode plate of the third combined quartz plate output positive charges, and the Z-direction electrode plate thereof outputs negative charges; the Y-direction electrode plate of the fourth combined quartz plate outputs positive charges, and the X-direction electrode plate and the Z-direction electrode plate thereof output negative charges.

4. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 1 is characterized in that: The four-point layout three-dimensional force piezoelectric sensor also includes an upper cover plate and a lower cover plate. The upper cover plate is arranged between the upper pressing plate and the piezoelectric material, and the lower cover plate is arranged between the piezoelectric material and the lower pressing plate.

5. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 1 is characterized in that: The upper pressure plate, the upper cover plate and the lower cover plate are annular structures, and the four-point layout three-dimensional force piezoelectric sensor also includes connecting screws, which connect the upper pressure plate, the upper cover plate, the lower cover plate and the lower pressure plate in sequence.

6. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 5 is characterized in that: The number of the connecting screws is eight, four of which are used to fix the piezoelectric material, and the remaining four connecting screws are respectively arranged between two adjacent piezoelectric materials.

7. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 1 is characterized in that: The four-point layout three-dimensional force piezoelectric sensor also includes a screw sleeve that is arranged in cooperation with the connecting screw. The screw sleeve is fixedly arranged in the receiving space, and the combined quartz plate is sleeved on the screw sleeve.

8. The structural self-decoupling four-point layout three-dimensional force piezoelectric sensor according to claim 1 is characterized in that: The number of the radio frequency adapters is three, and the three radio frequency adapters are all arranged on the outer surface of the outer sleeve.

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