A waterproof stick-type impact hammer

Abstract

The present invention discloses a waterproof rod-type impact hammer, which relates to the field of sensor technology, and comprises a rod-type hammer body; the front end of the rod-type hammer body is connected to a force sensor, and the front end of the force sensor is connected to a buffer head; the end face of the buffer head is in contact with the front end of the force sensor; the force sensor comprises a support body, an inner cavity passing through both ends of the support body, the tail end of the support body is sealed and connected to the rod-type hammer body, and the front end of the support body is provided with a sealing structure; the rod-type hammer body is provided with a cable channel, and a cable line is arranged in the cable channel, one end of the cable line is connected to the force sensor, and the other end of the cable line is connected to an impedance converter. The present scheme can be used for dynamic characteristic testing of elastic structures immersed in liquid in a closed container.

Description

Technical Field

[0001] The invention relates to the technical field of sensors, and in particular to a waterproof rod-type impact hammer. Background Art

[0002] For the dynamic characteristics test of the elastic structure immersed in liquid in a closed container, the traditional impact hammer cannot excite the elastic structure. The current implementation method is basically to open a hole in the closed container and install a sealing structure, and then use an exciter to vibrate the elastic structure to complete the modal test.

[0003] However, for some small structures and small container installation space, the use of the exciter becomes extremely difficult or even impossible. The present invention proposes a new solution to the above problems. Summary of the invention

[0004] The present invention aims to solve the deficiencies of the prior art and to provide a waterproof rod-type impact hammer. The present invention can be used for dynamic characteristic testing of elastic structures immersed in liquid in a closed container.

[0005] The present invention is achieved through the following technical solutions:

[0006] A waterproof stick-type impact hammer, comprising a stick-type hammer body;

[0007] The front end of the rod-type hammer is connected to a force sensor, and the front end of the force sensor is connected to a buffer head; the end surface of the buffer head is in contact with the front end of the force sensor;

[0008] The force sensor comprises a support body, an inner cavity extending through both ends of the support body, a rear end of the support body and the rod-type hammer body being sealed and connected, and a sealing structure being provided at the front end of the support body;

[0009] The rod-type hammer body is provided with a cable channel, in which a cable is arranged, one end of the cable is connected to the force sensor, and the other end of the cable is connected to an impedance converter.

[0010] Compared with the prior art, the use of exciters becomes extremely difficult or even impossible to use in some situations where the structure is small and the container installation space is narrow. The present invention provides a waterproof rod-type impact pulse hammer for dynamic characteristics testing of elastic structures immersed in liquid in a closed container. The specific scheme includes a rod-type hammer, a force sensor and a buffer head. The force sensor is arranged at the front end of the rod-type hammer, and the buffer head is arranged at the front end of the force sensor. The buffer head can adopt a low-frequency buffer head, a medium-frequency buffer head, a medium-high frequency buffer head and a high-frequency buffer head; the lower end of the buffer head is in direct contact with the front end surface of the force sensor; the force sensor includes a support body, which is similar to a hollow cylinder with a cavity inside. The internal parts of the force sensor are all located in the cavity, and a waterproof sealed space is formed through a sealed connection between the rear end of the support body and the rod-type hammer seal, and a sealing structure at the front end of the support body; the rod-type hammer is made of stainless steel metal material and has a hollow design. The hollow part is a cable channel, which should be as small as possible while ensuring that the cable can pass through, so as to ensure the rigidity of the rod-type hammer; the cable is connected to an impedance converter, which is installed near the tail of the hammer and connected to the SMA connector, and the output signal of the impedance converter is transmitted by the SMA. In the specific operation process, the device is installed in a special sealing structure on a closed container, and the waterproof rod-type impact hammer passes through the sealing hole to ensure that the front half of the hammer is in the closed container, and the buffer head can contact the structure to be tested. By striking the rear end of the hammer body, the dynamic characteristics test of the structure to be tested immersed in the liquid in the closed container can be achieved. The present invention can replace the exciter to a large extent to perform the dynamic characteristics test of the structure.

[0011] Further optimization, the internal parts of the force sensor include a membrane body, a connecting column is provided in the middle of one end of the membrane body, a connecting block is provided inside the support body, the end of the connecting column extends outward and is connected to the connecting block; the other end of the membrane body is connected to the buffer head; an annular clamping space is provided between one end of the membrane body and the connecting block, a clamping piece is provided in the annular clamping space, the clamping piece includes a plurality of crystal rings and conductive ring sheets, and the plurality of crystal rings and conductive ring sheets are alternately and closely arranged in sequence along the axial direction in the annular clamping space; one end of the cable is connected to a plurality of conductive ring sheets; it is used to achieve a compact arrangement of the internal parts of the force sensor.

[0012] Further optimization is that the connecting column is provided with threads, a threaded hole is opened in the middle of the connecting block, and the membrane body is threadedly connected to the connecting block through the connecting column; so as to realize the detachable connection of the membrane body.

[0013] For further optimization, the connecting column is also provided with a limiting groove, and the limiting groove prevents the membrane body from rotating.

[0014] Further optimization, the internal parts of the force sensor also include an insulating ring, which is circumferentially arranged along the outer end of the clamp; wherein the insulating ring is circumferentially arranged along the circumferential outer side of the crystal ring and the conductive ring sheet, thereby separating the crystal ring and external parts to achieve insulation.

[0015] Further optimized, the sealing structure includes a sealing metal sheet, the other end of the membrane body has a reduced diameter section, and the sealing metal sheet is arranged between the annular end of the reduced diameter section and the front end of the support body; it is used to achieve sealing while having a certain rigidity.

[0016] Further optimized, the sealing structure also includes a rubber membrane, which is arranged between the annular outer side of the membrane step and the inner side of the support body, and the rubber membrane is connected to the inner side of the support body through a sealing ring; so as to achieve a double sealing effect.

[0017] Further optimization, the other end of the membrane body is provided with a stud bolt, and the membrane body is connected to the buffer head via the stud bolt; and is used to realize a variety of dynamic characteristic testing methods.

[0018] Further optimization is that the other end of the membrane body and the end of the buffer head are both provided with a thread groove connected to the stud bolt; by arranging a thread groove at the end of the reduced diameter section of the membrane body and the lower end of the buffer head, the installation and replacement of the stud bolt can be achieved.

[0019] Further optimization is that the rear end of the support body and the front end of the rod-type hammer body are connected by welding; the waterproofness of the front end part of the hammer is ensured by the welding connection.

[0020] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0021] 1. The waterproof rod-type impact hammer provided by the present invention can be applied to some closed containers that cannot use an exciter for dynamic characteristic testing due to their small structure volume and narrow container installation space. Through the corresponding sealing and waterproof structure, it can be used for dynamic characteristic testing of elastic structures immersed in liquid in closed containers.

[0022] 2. The waterproof rod-type impact hammer provided by the present invention has two usage modes through a detachable buffer head: (1) through a special sealing structure installed on a closed container, the waterproof rod-type impact hammer of the present invention is passed through a sealing hole to ensure that the front half of the hammer is in the closed container, and the buffer head is in contact with the structure to be tested. By striking the rear end of the hammer body, the dynamic characteristics test of the structure to be tested immersed in liquid in the closed container is achieved; (2) the buffer head is removed, and the waterproof rod-type impact hammer of the present invention is passed through the sealing hole through a special sealing structure installed on the closed container, and the hammer is connected to the structure to be tested using a stud bolt. By striking the rear end of the hammer body, the dynamic characteristics test of the structure to be tested immersed in liquid in the closed container is achieved. The present invention can replace the exciter to a large extent to perform dynamic characteristics test of the structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0024] Figure 1 A cross-sectional view of a waterproof rod-type impact hammer provided by the present invention;

[0025] Figure 2 A cross-sectional view of the force sensor provided by the present invention.

[0026] Marks and corresponding parts names in the attached drawings:

[0027] 1- rod-type hammer, 2- force sensor, 21- support body, 22- membrane body, 23- crystal ring, 24- conductive ring sheet, 25- insulating ring, 26- sealing metal sheet, 27- rubber membrane, 28- sealing ring, 29- locking nut, 3- buffer head, 4- stud bolt, 5- cable, 6- impedance converter, 7- SMA connector. DETAILED DESCRIPTION

[0028] In the following description, a large number of specific details are set forth in order to provide a thorough understanding of the present invention. However, it is apparent to one of ordinary skill in the art that these specific details are not necessarily employed to practice the present invention. In other embodiments, in order to avoid obscuring the present invention, well-known structures, circuits, materials, or methods are not specifically described.

[0029] Throughout the specification, references to "one embodiment," "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "one embodiment," "an embodiment," "an example," or "an example" appearing in various places throughout the specification do not necessarily all refer to the same embodiment or example. In addition, particular features, structures, or characteristics may be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. In addition, it will be appreciated by those of ordinary skill in the art that the figures provided herein are for illustrative purposes and that the figures are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0030] In the description of the present invention, the directions or positional relationships indicated by terms such as “front”, “rear”, “left”, “right”, “up”, “down”, “vertical”, “horizontal”, “high”, “low”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the scope of protection of the present invention.

[0031] Example

[0032] This embodiment provides a waterproof rod-type impact hammer, such as Figure 1 and Figure 2 As shown, it includes a rod-type hammer body 1;

[0033] A force sensor 2 is connected to the front end of the rod-type hammer body 1, and a buffer head 3 is connected to the front end of the force sensor 2; the end surface of the buffer head 3 is in contact with the front end of the force sensor 2;

[0034] The force sensor 2 includes a support body 21, an inner cavity extending through both ends of the support body 21, a rear end of the support body 21 and a rod-type hammer body 1 being sealed and connected, and a front end of the support body 21 having a sealing structure;

[0035] The rod-type hammer body 1 has a cable channel in it. A cable 5 is arranged in the cable channel. One end of the cable 5 is connected to the force sensor 2 , and the other end of the cable 5 is connected to the impedance converter 6 .

[0036] Compared with the prior art, the use of exciters becomes extremely difficult or even impossible to use in some situations where the structure is small and the container installation space is narrow. The present invention provides a waterproof rod-type impact pulse hammer for dynamic characteristics testing of elastic structures immersed in liquid in a closed container. In the specific scheme, a rod-type hammer 1, a force sensor 2 and a buffer head 3 are included. The force sensor 2 is arranged at the front end of the rod-type hammer 1, and the buffer head 3 is arranged at the front end of the force sensor 2. The buffer head 3 can adopt a low-frequency buffer head 3, a medium-frequency buffer head 3, a medium-high frequency buffer head 3 and a high-frequency buffer head 3; the lower end of the buffer head 3 is in direct contact with the front end surface of the force sensor 2; the force sensor 2 includes a support body 21, and the support body 21 is similar to a hollow cylinder with a cavity therein. The internal parts of the force sensor 2 are all located in the cavity, and a waterproof sealed space is formed through the sealed connection between the rear end of the support body 21 and the rod-type hammer 1, and the sealing structure at the front end of the support body; the rod-type hammer 1 is made of stainless steel metal material and has a hollow design. The hollow part is a cable channel, which should be as small as possible while ensuring that the cable 5 can pass through, so as to ensure the rigidity of the rod-type hammer 1; the cable 5 is connected to an impedance transformer 6, which is installed near the tail of the hammer and connected to the SMA connector 7, and the output signal of the impedance transformer 6 is transmitted by the SMA. In the specific operation process, the device is installed in a special sealing structure on a closed container, and the waterproof rod-type impact hammer passes through the sealing hole to ensure that the front half of the hammer is in the closed container, and the buffer head 3 can contact the structure to be tested. By striking the rear end of the hammer body, the dynamic characteristics test of the structure to be tested immersed in the liquid in the closed container can be achieved. The present invention can replace the exciter to a large extent to perform the dynamic characteristics test of the structure.

[0037] See also Figure 2 As a specific implementation method for realizing the compact arrangement of the internal parts of the force sensor 2, it is set as follows: the internal parts of the force sensor 2 include a membrane body 22, a connecting column is provided in the middle of one end of the membrane body 22, a connecting block is provided on the inner side of the support body 21, and the end of the connecting column extends outward and is connected to the connecting block; the other end of the membrane body 22 is connected to the buffer head 3; an annular clamping space is provided between one end of the membrane body 22 and the connecting block, a clamping member is provided in the annular clamping space, and the clamping member includes a plurality of crystal rings 23 and conductive ring pieces 24, and the plurality of crystal rings 23 and conductive ring pieces 24 are alternately and closely arranged in sequence along the axial direction in the annular clamping space; one end of the cable 5 is connected to the plurality of conductive ring pieces 24;

[0038] It can be understood that, in the present embodiment, the force sensor 2 includes a membrane body 22, one end of the membrane body 22 is connected to a connecting block on the inner side of the support body 21 through an outwardly extending connecting column, thereby leaving an annular clamping space between the membrane body 22 and the connecting block, in which a plurality of crystal rings 23 and conductive ring pieces 24 are arranged, and the present scheme preferably arranges two crystal rings 23 and two conductive ring pieces 24, the crystal ring 23 and the conductive ring piece 24 are coaxially sleeved on the connecting column, and in the annular clamping space, they are closely arranged in the order of crystal ring 23-conductive ring piece 24-crystal ring 23-conductive ring piece 24, and the two conductive ring pieces 24 are both connected to the cable 5, thereby outputting the signal of the force sensor 2 to the impedance converter 6 through the cable 5.

[0039] Please continue reading Figure 2 As a specific implementation method for realizing the detachable connection of the membrane body 22, it is set as follows: the connection column is provided with threads, a threaded hole is opened in the middle of the connection block, and the membrane body 22 is threadedly connected to the connection column and the connection block;

[0040] It can be understood that in this embodiment, the connecting column has its own thread and is threadedly connected to the threaded hole in the middle of the connecting block, thereby achieving quick removal and replacement; the end of the connecting column extends out of the threaded hole and is screwed with a locking nut to fix the membrane body 22.

[0041] As a redundant solution, a limiting groove is further provided on the connecting column; the limiting groove prevents the membrane body 22 from rotating.

[0042] Please continue reading Figure 2 In this embodiment, the internal parts of the force sensor 2 also include an insulating ring 25, which is circumferentially arranged along the outer end of the clamping member; wherein the insulating ring 25 is circumferentially arranged along the outer circumference of the crystal ring 23 and the conductive ring sheet 24, thereby separating the crystal ring 23 from the external parts to achieve insulation.

[0043] Please continue reading Figure 2 As a specific implementation method for achieving sealing and having a certain rigidity, it is set as follows: the sealing structure includes a sealing metal sheet 26, the other end of the membrane body 22 has a reduced diameter section, and the sealing metal sheet 26 is arranged between the annular end of the reduced diameter section and the front end of the support body 21;

[0044] It can be understood that, in the present embodiment, the sealing structure includes a sealing metal sheet 26, and the sealing metal sheet 26 circumferentially seals the gap between the end of the reduced diameter section and the front end of the support body 21, thereby playing a sealing role. By adopting the metal sheet, the front end of the force sensor 2 can have a certain rigidity to avoid deformation due to force, which affects the sealing effect.

[0045] Please continue reading Figure 2As a specific implementation method for achieving a double sealing effect, it is configured as follows: the sealing structure further includes a rubber membrane 27, the rubber membrane 27 is arranged between the outer side of the membrane body 22 at the step and the inner side of the support body 21, and the rubber membrane 27 is connected to the inner side of the support body 21 through a sealing ring 28;

[0046] It can be understood that in this embodiment, the membrane body 22 forms a step in the middle of the side wall through the reduced diameter section at the front end, and a rubber membrane 27 is arranged between the circumferential outer side of the step and the inner side of the support body 21. The rubber membrane 27 can achieve a double sealing effect. If the sealing metal sheet 26 fails, the rubber membrane 27 can further play a protective role.

[0047] See also Figure 1 , as a specific implementation method for realizing multiple dynamic characteristic testing methods, it is set as follows: the other end of the membrane body 22 is provided with a stud bolt 4, and the membrane body 22 is connected to the buffer head 3 through the stud bolt 4;

[0048] It can be understood that in this embodiment, the membrane body 22 and the buffer head 3 are connected by the stud bolt 4, so that the buffer head 3 can be disassembled and assembled. The present invention can realize two dynamic characteristic testing methods through the detachable buffer head 3: (1) through the special sealing structure installed on the closed container, the waterproof rod type impact hammer of the present invention is passed through the sealing hole to ensure that the front half of the hammer is in the closed container, and the buffer head 3 is in contact with the structure to be tested, and the dynamic characteristic test of the structure to be tested immersed in the liquid in the closed container is realized by striking the rear end of the hammer body; (2) the buffer head 3 is disassembled, and the waterproof rod type impact hammer of the present invention is passed through the sealing hole through the special sealing structure installed on the closed container, and the hammer is connected to the structure to be tested using the stud bolt 4, and the dynamic characteristic test of the structure to be tested immersed in the liquid in the closed container is realized by striking the rear end of the hammer body.

[0049] As a redundant solution, the other end of the membrane body 22 and the end of the buffer head 3 are both provided with threaded grooves connected to the stud bolts 4; by providing threaded grooves at the end of the reduced diameter section of the membrane body 22 and the lower end of the buffer head 3, the installation and replacement of the stud bolts 4 can be achieved.

[0050] As a redundant solution, the rear end of the support body 21 and the front end of the rod-type hammer body 1 are connected by welding; the waterproofness of the front end of the hammer is ensured by the welding connection.

[0051] Specific working principle: The present invention provides two main usage modes:

[0052] (1) The hammer head (with a buffer head 3 installed) is aligned with the excitation point of the structure to be measured;

[0053] (2) The hammer body (without the buffer head 3 installed) is connected to the excitation point of the structure under test through the stud bolt 4.

[0054] The above two usage methods are to hammer with the other end of the hammer, and the membrane 22 of the force sensor 2 collides with the excited structure to generate pulse excitation, generate corresponding deformation and transmit it to the piezoelectric quartz chip of the force sensor 2. In terms of electrical performance, the positive piezoelectric effect of piezoelectricity is used to make the piezoelectric quartz chip generate a charge signal, which is transmitted to the impedance converter 6 through the cable 5. The impedance converter 6 converts the charge signal into impedance and outputs a low-impedance voltage signal, which outputs the corresponding electrical signal through the SMA connector 7. The SMA connector 7 provides the signal to a special instrument for signal conditioning and analysis. At the same time, the special instrument provides working power to the impedance converter 6 through the SMA connector.

[0055] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A waterproof rod-type impact hammer, characterized in that: It comprises a rod-type hammer body (1); The front end of the rod-type hammer (1) is connected to a force sensor (2), and the front end of the force sensor (2) is connected to a buffer head (3); the end surface of the buffer head (3) is in contact with the front end of the force sensor (2); The force sensor (2) comprises a support body (21), the support body (21) has inner cavities extending through both ends, the rear end of the support body (21) is sealedly connected to the rod-type hammer body (1), and the front end of the support body (21) is provided with a sealing structure; The rod-type hammer body (1) has a cable channel in it, a cable (5) is arranged in the cable channel, one end of the cable (5) is connected to the force sensor (2), and the other end of the cable (5) is connected to an impedance converter (6); The internal parts of the force sensor (2) include a membrane body (22), a connecting column is provided in the middle of one end of the membrane body (22), a connecting block is provided on the inner side of the support body (21), and the end of the connecting column extends outward and is connected to the connecting block; the other end of the membrane body is connected to the buffer head (3); an annular clamping space is provided between one end of the membrane body (22) and the connecting block, a clamping member is provided in the annular clamping space, and the clamping member includes a plurality of crystal rings (23) and conductive ring sheets (24), and the plurality of crystal rings (23) and conductive ring sheets (24) are alternately and closely arranged in sequence along the axial direction in the annular clamping space; one end of the cable (5) is connected to the plurality of conductive ring sheets (24); The sealing structure comprises a sealing metal sheet (26), the other end of the membrane body is provided with a reduced diameter section, and the sealing metal sheet (26) is arranged between the annular end of the reduced diameter section and the front end of the support body (21); The other end of the membrane body (22) is provided with a stud bolt (4), and the membrane body (22) is connected to the buffer head (3) via the stud bolt (4).

2. A waterproof rod-type impact hammer according to claim 1, characterized in that: The connecting column is provided with threads, a threaded hole is provided in the middle of the connecting block, and the membrane body (22) is threadedly connected to the connecting block via the connecting column.

3. A waterproof rod-type impact hammer according to claim 2, characterized in that: The connecting column is also provided with a limiting groove.

4. A waterproof rod-type impact hammer according to claim 1, characterized in that: The internal parts of the force sensor (2) further include an insulating ring (25), wherein the insulating ring (25) is arranged in a circumferential direction along the outer end of the clamping member.

5. A waterproof rod-type impact hammer according to claim 1, characterized in that: The sealing structure further comprises a rubber membrane (27), wherein the rubber membrane (27) is arranged between the annular outer side of the step of the membrane body (2) and the inner side of the support body (21), and the rubber membrane (27) is connected to the inner side of the support body (21) via a sealing ring (28).

6. A waterproof rod-type impact hammer according to claim 1, characterized in that: The other end of the membrane body (22) and the end of the buffer head (3) are both provided with a threaded groove connected to the stud bolt (4).

7. A waterproof rod-type impact hammer according to claim 1, characterized in that: The rear end of the support body (21) and the front end of the rod-type hammer body (1) are connected by welding.

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