A sensor having an out-of-plane sensitive MEMS accelerometer

Abstract

The application discloses a sensor with an out-of-plane sensitive MEMS accelerometer, which comprises a sensor body, a cable and a cable locking mechanism for locking the cable on the sensor body. The sensor body comprises a base, a collection plate and a conditioning plate. The collection plate is arranged horizontally, with a front surface attached to the front end surface of the inner cavity of the base and a rear surface attached to the out-of-plane sensitive MEMS accelerometer. The conditioning plate is arranged longitudinally, with a front end abutting against the rear surface of the collection plate. The cable extends from the rear end of the sensor body and is connected to the conditioning plate. The cable locking mechanism comprises a gland seat, a gland and a sealing ring. The gland seat is provided with a through hole. The sealing ring is sleeved on the outer periphery of the cable and arranged in the through hole. The gland is arranged in the through hole and used for pressing the sealing ring against the cable. Compared with the prior art, the application can effectively improve the reliability of vibration impact signal collection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of detection, in particular to a sensor with a face-out sensitive MEMS accelerometer. BACKGROUND

[0002] In the rail transit industry, the vehicle runs at high speed, and the rotating parts of the running gear are prone to high temperature and excessive vibration and impact, and the motor, gear box and other rotating parts are prone to failure, affecting the safety of train operation. In order to ensure the safety of train operation, the temperature, vibration and impact signals of the axle box, motor and other rotating parts of the running gear prone to failure need to be monitored, and timely warning is needed when abnormal signals occur to prevent the vehicle from running with disease.

[0003] In the field of vibration and impact signal detection and fault diagnosis, foreign comb MEMS accelerometers are now commonly used as the core sensitive device of the sensor, with the sensitive axis in the in-plane direction. The MEMS accelerometer is horizontally attached to the PCB, and then installed inside the sensor shell with the PCB vertical and in the same direction as the signal. Only the cutting edge is in contact with the shell in the signal direction. This installation method has a complex signal transmission path, and in addition, the sensor structure has a packaging stress effect on the MEMS accelerometer, resulting in low detection accuracy of low-frequency and weak vibration and impact signals.

[0004] MEMS accelerometers based on capacitance detection principle do not require additional material effects compared to other piezoresistive and tunnel MEMS, have low temperature sensitivity, high sensitivity, good linearity and excellent low-frequency performance, and are gradually used for vibration and impact sensor detection and have achieved nationalization. The basic structure of capacitive MEMS accelerometers mainly includes comb, sandwich and torsional pendulum types. The comb type has an in-plane (XOY plane) acceleration sensitive direction, while the sandwich and torsional pendulum types have a face-out (Z-axis) acceleration sensitive direction. The torsional pendulum type and capacitive structure MEMS accelerometer with face-out direction has the characteristics of small size, light weight, high detection accuracy, impact resistance and easy batch processing, and has become the focus of domestic research, development and application.

[0005] In summary, how to provide a sensor that meets the requirements of the rail transit industry, can monitor temperature, vibration and impact, and has good signal reliability is a problem that needs to be solved by the technical personnel in the field. Practical new type content

[0006] To solve the above technical problems, the purpose of the present application is to provide a sensor with a face-out sensitive MEMS accelerometer with reliable detection.

[0007] The technical solutions provided by the present application are as follows:

[0008] A sensor with an out-of-plane sensitive MEMS accelerometer, comprising a sensor body, a cable and a cable locking mechanism for locking the cable to the sensor body; the sensor body comprises a base, a collection plate and a conditioning plate, the collection plate is arranged transversely, the front surface is attached to the front end surface of the inner cavity of the base, and the back surface is attached to the out-of-plane sensitive MEMS accelerometer, the conditioning plate is arranged longitudinally, the front end abuts against the back surface of the collection plate, and the collection plate and the conditioning plate are electrically connected through a flexible circuit board; the cable extends into the conditioning plate from the rear end of the sensor body; the cable locking mechanism comprises a gland, a gland cover and a sealing ring, the gland is arranged in the sensor base and connected to the inner wall of the sensor base, and the rear end of the conditioning plate abuts against the gland to press the collection plate against the front end surface of the inner cavity of the base, the gland is provided with a through hole, the sealing ring is sleeved on the outer periphery of the cable and arranged in the through hole, and the gland cover is arranged in the through hole to press the sealing ring against the cable.

[0009] Preferably, an elastic member is arranged between the gland and the conditioning plate, the elastic member is provided with a wire passing hole for the cable to pass through, and the gland presses the conditioning plate through the elastic member.

[0010] Preferably, the conditioning plate is fixed above the collection plate by a mortise and tenon method, the collection plate and the conditioning plate each have N layers, and M layers of the N layers are flexible layers, and the M flexible layers are connected one by one with corresponding layers of the flexible circuit board; wherein M and N are positive integers, respectively representing the number of layers of the flexible circuit board and the collection plate and the conditioning plate, and M≤N.

[0011] Preferably, the conditioning plate is fixed above the collection plate by a mortise and tenon method, specifically, the collection plate is provided with a groove, the conditioning plate is fixed on the collection plate through the groove, and the groove provided on the collection plate comprises a first groove and a second groove; the conditioning plate has a first connecting end and a second connecting end, the first connecting end is inserted into the first groove, and the second connecting end is inserted into the second groove.

[0012] The first connecting end has an L-shaped structure in the thickness direction for cooperating with the first groove, and the second connecting end has an L-shaped structure in the thickness direction for cooperating with the second groove.

[0013] Or;

[0014] The first connecting end has an L-shaped structure in the length direction for cooperating with the first groove, and the second connecting end has an L-shaped structure in the length direction for cooperating with the second groove.

[0015] Preferably, it further comprises a stress isolation cover arranged on the accelerometer for isolating the stress of the potting glue filled in the inner cavity of the base from the accelerometer.

[0016] Preferably, the middle of the front end of the conditioning plate is provided with a first groove for avoiding the accelerometer, and the middle of the rear end is provided with a second groove for avoiding the cable.

[0017] Preferably, the outer side of the front end face of the inner cavity corresponding to the placement of the acquisition plate is an annular tapered surface, so that the vibration impact signals generated by the measured device are transmitted to the front end face of the inner cavity through the annular tapered surface on the base; the front end of the base is provided with a stud for rigid installation on the measured device; the sensor body further comprises a temperature sensitive device, and the stud is internally provided with a temperature sensitive device accommodating cavity in communication with the inner cavity; the temperature sensitive device is accommodated in the temperature sensitive device accommodating cavity and electrically connected with the acquisition plate.

[0018] Preferably, the front end of the conditioning plate is provided with a clearance cut for avoiding the annular tapered surface.

[0019] Preferably, the front end of the gland is sleeved on the outer periphery of the sealing ring to press the sealing ring tightly on the outer periphery of the cable, and the rear end of the gland is used to sleeve on the outer periphery of the cable; a wire protection spring is arranged between the gland and the cable, the front end of the wire protection spring is arranged between the gland and the sealing ring, and the rear end of the wire protection spring extends along the rear end of the gland; the through hole of the gland seat is a stepped through hole, the stepped through hole comprises a first annular stepped surface and a second annular stepped surface arranged on the inner periphery of the stepped through hole, the first annular stepped surface is arranged on the front side of the second annular stepped surface, the outer diameter of the first annular stepped surface is equal to the inner diameter of the second annular stepped surface, the sealing ring is arranged on the first annular stepped surface, and the gland is arranged on the second annular stepped surface; the outer side of the gland is provided with a nylon hose and a pressing mechanism for locking the nylon hose, the pressing mechanism comprises a cap and a rubber sleeve arranged on the inner wall of the cap; the cap is arranged on the inner wall of the gland seat; the inner periphery of the through hole of the gland seat is provided with a third annular stepped surface, the third annular stepped surface is arranged on the rear side of the second stepped surface, and the outer diameter of the second stepped surface is equal to the inner diameter of the third annular stepped surface; the cap is arranged on the third stepped surface; the rear end of the gland seat is flush with the rear end of the cap, so as to be flush with the rear end of the sensor base; the middle of the inner wall of the base is provided with a stepped surface for placing the gland seat.

[0020] Preferably, the inner wall of the rear end of the cap is provided with an annular reverse hook for extruding the rubber sleeve; the inner wall of the rubber sleeve is provided with at least one second annular protrusion for cooperating with the nylon hose; when the number of the second annular protrusions is greater than one, all the second annular protrusions are arranged in sequence along the axial direction of the rubber sleeve.

[0021] Preferably, the elastic member is made of insulating material, and the elastic member is used to insulate and isolate the conditioning plate and the gland seat.

[0022] The utility model discloses a sensor with out-of-plane sensitive MEMS accelerometer relative to the prior art, provide the downward pressure through the gland seat in the cable locking mechanism and fix the board card assembly firmly in the base, and the collection board is tightly attached to the inner chamber of base, can effectively improve the reliability of vibration impact signal collection, and at the same time, through the elastic piece provides insulation and buffering effect, guarantee the reliability of sensor. Further, the out-of-plane sensitive MEMS accelerometer is attached on the collection board, and the collection board is attached on the base, which simplifies the signal transmission path, increases the contact area of the base and the MEMS accelerometer, makes the MEMS accelerometer more easily receive vibration and impact signals, can truly and sensitively feel vibration and impact signals, and can minimize the transmission attenuation of impact signals, improves the reliability of sensor signals. Further, the conditioning board and the collection board are vertically installed through the mortise and tenon structure, which can effectively reduce the volume of the sensor and meet the installation needs of narrow space. The design of the shape and structure of the sensor meets the installation needs of the monitoring position of the axle box, motor and other running parts of urban rail transit vehicles (subway). BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments described in the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0024] Figure 1 The utility model discloses a sensor with out-of-plane sensitive MEMS accelerometer relative to the prior art, provide the downward pressure through the gland seat in the cable locking mechanism and fix the board card assembly firmly in the base, and the collection board is tightly attached to the inner chamber of base, can effectively improve the reliability of vibration impact signal collection, and at the same time, through the elastic piece provides insulation and buffering effect, guarantee the reliability of sensor. Further, the out-of-plane sensitive MEMS accelerometer is attached on the collection board, and the collection board is attached on the base, which simplifies the signal transmission path, increases the contact area of the base and the MEMS accelerometer, makes the MEMS accelerometer more easily receive vibration and impact signals, can truly and sensitively feel vibration and impact signals, and can minimize the transmission attenuation of impact signals, improves the reliability of sensor signals. Further, the conditioning board and the collection board are vertically installed through the mortise and tenon structure, which can effectively reduce the volume of the sensor and meet the installation needs of narrow space. The design of the shape and structure of the sensor meets the installation needs of the monitoring position of the axle box, motor and other running parts of urban rail transit vehicles (subway).

[0025] Figure 2 For Figure 1 The sectional view of the front end part of the sensor shown in the figure.

[0026] Figure 3 For Figure 1 The sectional view of the base in the sensor shown in the figure.

[0027] Figure 4 For Figure 1 The perspective view of the circuit board module in the sensor shown in the figure.

[0028] Figure 5 For Figure 4 The expanded perspective view of the circuit board module shown in the figure. DETAILED DESCRIPTION

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] like Figures 1 to 5 As shown, this embodiment of the present invention provides a sensor with an out-of-plane sensitive MEMS accelerometer, mainly comprising a sensor body 1, a cable 2, and a connector 3 connected in sequence. A cable locking mechanism 4 is provided between the sensor body 1 and the cable 2 to lock the cable 2 onto the sensor body 1.

[0031] In this embodiment, the sensor body 1 mainly includes a housing 11, a data acquisition board 12, a conditioning board 13, a flexible circuit board 14, a temperature-sensitive device 15, etc.

[0032] In this embodiment, the housing 11 includes a base 111 with an inner cavity. The acquisition plate 12, conditioning plate 13, and flexible circuit board 14 are accommodated in the inner cavity.

[0033] In this embodiment, the acquisition board 12 is used to acquire vibration and impact signals. It is horizontally positioned, with its front surface attached to the front end face of the inner cavity of the base 111, and its rear surface attached to an out-of-plane sensitive MEMS accelerometer 16. The out-of-plane sensitive MEMS accelerometer 16 can be a butterfly-wing MEMS accelerometer, a Colibrys capacitive accelerometer, or a single torsion pendulum MEMS accelerometer. A stress isolation cover 17 is provided above the accelerometer 16 to isolate the accelerometer 16 from the potting compound filling the inner cavity of the base 111. The stress isolation cover 17 is a rectangular box-shaped structure with one open end, which can prevent the potting compound from deforming due to temperature changes and causing stress on the accelerometer 16, thereby stabilizing the zero-point output (stress on the accelerometer 16 will cause zero-point output drift, resulting in inaccurate low-frequency or low-amplitude signals). The acquisition board 12 has an opening 121 in the middle for connecting the lead wire 151 of the temperature-sensitive device 15.

[0034] In this embodiment, the conditioning plate 13 is used to condition and output the collected vibration and impact signals. It is arranged longitudinally, with its front end abutting against the rear surface of the acquisition plate 12 and its rear end abutting against the cable locking mechanism 4. The cable extends from the rear end of the sensor body 1 and connects to the conditioning plate 13. The conditioning plate 13 has a first groove 131 at the middle of its front end to avoid the accelerometer 16 and a second groove 132 at the middle of its rear end to avoid the cable 2, forming an H-shape overall. The two sides of the front end of the conditioning plate 13 have clearance edges 133 to allow the annular conical surface of the base 111 to pass.

[0035] In the embodiment, the conditioning plate 13 is fixed above the collection plate 12 in a mortise and tenon manner, and has an inverted T shape. The collection plate 12, the conditioning plate 13 and the flexible circuit board 14 are preassembled to form a circuit board module. The inverted T shape can effectively increase the stability of the circuit board module.

[0036] The mortise and tenon manner is that the collection plate 12 is provided with a groove, and the conditioning plate is fixed on the collection plate 12 through the groove. The groove provided on the collection plate 12 includes a first groove 122 and a second groove 123 located on the two sides respectively. The conditioning plate has a first connecting end 134 and a second connecting end 135. The first connecting end 134 is inserted into the first groove 122, and the second connecting end 135 is inserted into the second groove 123. The first connecting end 134 has an L-shaped structure in the thickness direction for cooperating with the first groove 122, and the second connecting end 135 has an L-shaped structure in the thickness direction for cooperating with the second groove 123. In other embodiments, the L-shaped structure can also be arranged in other directions, for example, it can be in the length direction, that is, the first connecting end has an L-shaped structure in the length direction for cooperating with the first groove, and the second connecting end has an L-shaped structure in the length direction for cooperating with the second groove.

[0037] In the embodiment, the collection plate 12 and the conditioning plate 13 are connected through the flexible circuit board 14. The collection plate 12 and the conditioning plate 13 are designed as a combination of soft and hard boards, that is, the flexible circuit board 14 is an M-layer soft board, and the collection plate 12 and the conditioning plate 13 have N layers, M≤N. M layers in the N layers are flexible layers, so that the M-layer flexible layers in the collection plate 12 and the conditioning plate 13 can be connected one by one with the corresponding layers of the flexible circuit board 14.

[0038] In actual application, the flexible circuit board 14 will adopt a soft board with flexibility, high temperature resistance and high insulation, and the thickness is generally less than 0.2 mm. It is usually arranged as one layer or two layers, and it is usually connected to the top or bottom of the collection plate 12 and the conditioning plate 13. For example, in one occasion, M=2, that is, the flexible circuit board 14 is a 2-layer soft board. The two layers of the flexible circuit board 14 can be connected with the first layer and the second layer of the collection plate 12 and the conditioning plate 13 respectively. The first layer and the second layer of the collection plate 12 and the conditioning plate 13 are flexible layers, and the first layer of the collection plate 12 and the conditioning plate 13 is the top layer. For another example, the two layers of the flexible circuit board 14 can be connected with the first layer and the second layer of the collection plate 12 and the conditioning plate 13 respectively. At this time, the first layer and the second layer of the collection plate 12 and the conditioning plate 13 are flexible layers, and the first layer of the collection plate 12 and the conditioning plate 13 is the bottom layer. Of course, in addition to being connected to the top or bottom of the collection plate 12 and the conditioning plate 13, in other embodiments, according to the needs, the appropriate M layers in the N layers can be selected as flexible layers and connected one by one with the corresponding layers of the flexible circuit board 14.

[0039] Therefore, due to the adoption of the soft and hard combined plate design of the collection plate 12 and the conditioning plate 13, the collection plate 12 and the conditioning plate 13 can be directly connected with the flexible circuit board 14 without the need of setting a special interface, and the connection position is not easy to be damaged due to bending, thus ensuring the reliability.

[0040] The outer side of the base 111 corresponding to the inner cavity front end surface where the collection plate 12 is attached is a ring-shaped conical surface 115, so that the vibration impact signal generated by the measured equipment is transmitted to the inner cavity front end surface on the base 111 through the ring-shaped conical surface 115. In the embodiment, the included angle of the ring-shaped conical surface 115 is 90 degrees.

[0041] In the embodiment, the base 111 is provided with a stud 112 at the front end, which is used for rigid installation on the measured equipment through the stud 112. The stud 112 is internally provided with a temperature sensitive device accommodating cavity 113 which is in communication with the inner cavity. The temperature sensitive device 15 is accommodated in the temperature sensitive device accommodating cavity 113 and is electrically connected with the collection plate 12. The stud 112 is provided with an opening at the front end, and the opening is closed by a round cover plate 18. The inner wall of the base 111 is further provided with a stepped surface 114 for placing a gland seat.

[0042] The cable locking mechanism 4 includes a gland seat 41 for connecting with the sensor base 111. The gland seat 41 is arranged in the sensor base 111 and is connected with the inner wall of the sensor base 111, and abuts against the rear end of the conditioning plate 13 to press the collection plate 12 against the inner cavity front end surface of the base 111. The gland seat 41 is provided with a through hole, and a sealing ring 42 for sleeving the outer periphery of the cable 2 is arranged in the through hole. A gland 43 for pressing the sealing ring 42 against the cable 2 is also arranged in the through hole. The elastic member 44 is arranged between the gland seat 41 and the conditioning plate 13, so that the gland seat 41 can press the conditioning plate 13 through the elastic member 44. The elastic member 44 can play a certain buffering role in the process of pressing the conditioning plate 13.

[0043] It should be noted that the gland seat 41 is a base for installing the sealing ring 42 and the gland 43. The outer side of the gland seat 41 is connected with the sensor base 111, and the sealing ring 42 and the gland 43 are connected with the inner side of the gland seat 41.

[0044] The sealing ring 42 is a sealing rubber ring. After the gland 43 is interference-fitted with the gland seat 41, the sealing rubber ring is compressed and deformed. Since the sealing rubber ring is sleeved on the outside of the cable 2, the sealing rubber ring can tightly hold the cable 2, reduce the stress of the circuit board 8 pad, and achieve the effect of waterproof and dustproof.

[0045] The grommet seat 41 can be fixedly connected with the sensor base 111, the front end of the grommet 43 is pressed into the through hole of the grommet seat 41, the inner wall of the through hole and the grommet 43 are in interference fit, and welding can also be performed at the connection to improve the fastening force between the grommet 43 and the grommet seat 41. In order to prevent the sealing ring 42 from moving axially, the sealing ring 42 can be pressed between the grommet 43 and the grommet seat 41, and the grommet 43 can press the outer periphery of the sealing ring 42 to provide radial fastening force for the sealing ring 42, so that the sealing ring 42 can tightly hold the cable 2, not only improving the waterproof and dustproof effect, but also improving the fixing effect of the cable 2.

[0046] After connecting the grommet seat 41 of the present application to the sensor base 111, the sealing ring 42 is sleeved on the outside of the cable 2 and is pressed into the through hole, and then the sealing ring 42 is fastened by the grommet 43, which can improve the fixing effect of the cable 2 and prevent the cable 2 from being broken due to excessive stress. In addition, since the sealing ring 42 is arranged between the through hole and the cable 2, water vapor, dust and the like can be prevented from entering the inside of the sensor, and the reliability of the sensor can be improved.

[0047] On the basis of the above-mentioned embodiments, as a further preferred, the front end of the grommet 43 is sleeved on the outer periphery of the sealing ring 42 to press the sealing ring 42 against the outer periphery of the cable 2, and the rear end of the grommet 43 is used to be sleeved on the outer periphery of the cable 2.

[0048] It should be noted that the length of the grommet 43 extending along the sealing ring 42 to the rear end can be set according to actual application, in the present embodiment, the rear end of the grommet 43 is basically flush with the rear end of the sensor base 111, in this way, appropriate extension of the grommet 43 can make the part of the cable 2 inside the grommet 43 not be bent too much, but only be bent slightly, thereby increasing the distance from the part of the cable 2 that can be bent greatly to the front end of the cable 2, and reducing the risk of disconnection of the cable 2 at the connection with the collection board 12.

[0049] On the basis of the above-mentioned embodiments, as a further preferred, the through hole is a stepped through hole, the stepped through hole includes a first annular stepped surface and a second annular stepped surface arranged on the inner periphery of the stepped through hole, the first annular stepped surface is arranged on the front side of the second annular stepped surface, the outer diameter of the first annular stepped surface is equal to the inner diameter of the second annular stepped surface, the sealing ring 42 is arranged on the first annular stepped surface, and the grommet 43 is arranged on the second annular stepped surface.

[0050] It should be noted that the outer periphery of the sealing ring 42 is provided with an annular fitting portion 421, the front end surface of the annular fitting portion 421 is an annular plane, and the annular fitting portion 421 is fitted with the first annular stepped surface. The outer surface of the annular fitting portion 421 is an annular surface, and is fitted with the inner wall of the through hole on the rear side of the first annular stepped surface. This arrangement can prevent the sealing ring 42 from moving axially towards the front end. Alternatively, the outer diameter of the annular fitting portion 421 can be slightly larger than the outer diameter of the first annular stepped surface, so that the annular fitting portion 421 is in interference fit with the inner wall of the through hole on the rear side of the first annular stepped surface, thereby increasing the fastening force between the sealing ring 42 and the gland seat 41.

[0051] The front end surface of the gland 43 is fitted with the second annular stepped surface, the front end outer periphery of the gland 43 is pressed into the inner wall of the through hole on the rear side of the second annular stepped surface, and the front outer periphery of the gland 43 is welded with the inner wall of the gland seat 41, thereby facilitating the direct connection of the gland seat 41 and the gland 43. This not only limits the axial movement of the gland 43 towards the front end, but also improves the stability of the connection between the gland 43 and the gland seat 41.

[0052] The rear end surface of the annular fitting portion 421 is a first circular stepped surface, the front end outer diameter of the first circular stepped surface is larger than the rear end outer diameter, and the first circular stepped surface is located on the rear side of the second annular stepped surface. The front end inner wall of the gland 43 is provided with a second circular stepped surface fitted with the first circular stepped surface, and the front end inner diameter of the second circular stepped surface is larger than the rear end inner diameter. When the front end surface of the gland 43 is completely fitted with the second annular stepped surface, the second circular stepped surface will press the first circular stepped surface, and the first circular stepped surface will be subjected to a pressing force towards the front end and radially inward, thereby pressing the sealing ring 42 against the first annular stepped surface and the cable 2.

[0053] The structure provided in the embodiment can improve the stability of the installation of the sealing ring 42, improve the stability of the installation of the gland 43, and improve the gripping force of the sealing ring 42 on the cable 2, thereby improving the sealing performance, reducing the deformation of the front end of the cable 2, and further preventing the cable 2 from being broken due to excessive stress.

[0054] On the basis of the above embodiment, as a further preferred embodiment, a wire protection spring 45 is arranged between the gland 43 and the cable 2, and the front end of the wire protection spring 45 is arranged between the first circular stepped surface and the second circular stepped surface.

[0055] It should be noted that the front end of the wire protection spring 45 is arranged between the first circular stepped surface and the second circular stepped surface, the wire protection spring 45 is pressed against the first circular stepped surface through the second circular stepped surface, and the rear end of the wire protection spring 45 is sleeved on the outer periphery of the cable 2. When the cable 2 is bent, the wire protection spring 45 can bend together with the cable 2 to ensure that the cable 2 does not interfere with the gland 43, and limits the bending degree of the cable 2, further preventing the cable 2 from being broken due to wear, and improving the service life of the cable 2.

[0056] The wire protection spring 45 has strong elasticity, and can be deformed with the cable 2 to a large extent after the cable 2 is bent, and can restore the original state, can be repeatedly bent, has a long service life, and is low in cost.

[0057] On the basis of the above embodiment, as a further preferred, the rear end of the wire protection spring 45 extends along the rear end of the gland 43. The embodiment can prevent the cable 2 from contacting the rear end of the gland 43 when bending, the wire protection spring 45 is between the cable 2 and the rear end of the gland 43, can increase the stress area of the cable 2, further prevent the cable 2 from breaking due to abrasion with the rear end of the gland 43, and improve the service life of the cable 2.

[0058] On the basis of the above embodiment, as a further preferred, the outer side of the gland 43 is provided with a compression mechanism for locking the nylon hose 48, the compression mechanism includes a cap 46 and a rubber sleeve 47 arranged on the inner wall of the cap 46; the cap 46 is arranged on the inner wall of the gland seat 41, or the front end of the cap 46 is sleeved on the outside of the rear end of the gland seat 41.

[0059] It should be noted that the cable 2 extends into the nylon hose 48, and the nylon hose 48 is compressed on the outer periphery of the gland 43 by the compression mechanism, and the compression mechanism is arranged on the gland seat 41, so that the compression mechanism is connected with the nylon hose 48 and the gland seat 41 respectively, to stably install the nylon hose 48.

[0060] The rear end of the gland seat 41 is interference-fitted into the front end inner wall of the cap 46, and then the connection between the gland seat 41 and the cap 46 is welded, and after installation, the cap 46 will radially extrude the rubber sleeve 47, so that the rubber sleeve 47 tightly holds the nylon hose 48, to prevent the nylon hose 48 from coming out.

[0061] Since the nylon hose 48 is directly connected with the gland seat 41 through the compression mechanism, and the cable 2 is wrapped with the nylon hose 48 when bending, the stress borne by the cable 2 is reduced, so that the cable 2 is not easy to break due to fatigue in a harsh operating environment.

[0062] On the basis of the above embodiment, as a further preferred, when the cap 46 is arranged on the inner wall of the gland seat 41, the third annular stepped surface is arranged on the inner periphery of the through hole of the gland seat 41, the third annular stepped surface is arranged on the rear side of the second stepped surface, the outer diameter of the second stepped surface is equal to the inner diameter of the third annular stepped surface; the cap 46 is arranged on the third stepped surface; the rear end of the gland seat 41 is flush with the rear end of the cap 46, to be flush with the rear end of the sensor base 111.

[0063] In this embodiment, the third annular stepped surface is parallel to the first annular stepped surface and the second annular stepped surface, the front end of the cap 46 is attached to the third annular stepped surface, and the outer periphery of the cap 46 is attached to the inner wall of the gland seat 41. The third annular stepped surface can prevent the gland seat 41 from moving axially towards the front end.

[0064] The rear end of the gland seat 41 is flush with the rear end of the cap 46, and at this time, the rear end of the sensor base 111 is arranged flush with the rear end of the gland seat 41, which not only allows the sensor base 111 to protect the internal structure such as the gland 43, but also reduces the overall length of the front end to the rear end of the sensor base 111, and can reduce the outer diameter of the sensor base 111, further reducing the occupied space of the sensor base 111.

[0065] On the basis of the above embodiment, as a further preferred, the inner wall of the rear end of the cap 46 is provided with an annular barb 461 for extruding the rubber sleeve 47.

[0066] It should be noted that the annular barb 461 protrudes radially inward along the inner wall of the rear end of the cap 46, and after the cap 46 is fitted around the outer periphery of the rubber sleeve 47, the annular barb 461 can press the rubber sleeve 47 to fit around the outer periphery of the nylon hose 48, preventing the rubber sleeve 47 from coming off the rear side of the cap 46.

[0067] On the basis of the above embodiment, as a further preferred, the outer periphery of the gland 43 is provided with at least one first annular protrusion 431 for cooperating with the nylon hose 48; when the number of first annular protrusions 431 is greater than one, all the first annular protrusions 431 are arranged in sequence along the axial direction of the gland 43.

[0068] It should be noted that since the nylon hose 48 adopts a corrugated tube, the tube wall has protrusions radially inward, and when the cap 46 presses the rubber sleeve 47 to press the tube wall, the tube wall will be pressed inwardly to the gland 43, at this time at least one protrusion of the tube wall will be at the front end of the first annular protrusion 431, and the inner diameter of the protrusion of the tube wall is smaller than the outer diameter of the first annular protrusion 431, the first annular protrusion 431 will limit the protrusion of the tube wall, so that the protrusion of the tube wall cannot easily move towards the rear end, thereby preventing the tube wall from being separated from the gland 43, and improving the stability of the connection between the nylon hose 48 and the gland 43.

[0069] Providing at least two first annular protrusions 431 can allow the protrusions of the tube wall to be at the front end of the first annular protrusion 431 and between adjacent first annular protrusions 431, thereby further increasing the limiting effect of the first annular protrusion 431 and further improving the stability of the connection between the nylon hose 48 and the gland 43.

[0070] On the basis of the above-mentioned embodiments, as a further preferred, the inner wall of the rubber sleeve 47 is provided with at least one second annular protrusion 471 for cooperating with the nylon hose 48; when the number of the second annular protrusions 471 is more than one, all the second annular protrusions 471 are arranged in sequence along the axial direction of the rubber sleeve 47.

[0071] It should be noted that, since the nylon hose 48 adopts a corrugated tube, the tube wall has radially outward protrusions, when the cap 46 presses the rubber sleeve 47, the rubber sleeve 47 will be pressed against the outer periphery of the tube wall, at this time, at least one protrusion of the tube wall will be at the front end of the second annular protrusion 471, and the outer diameter of the protrusion of the tube wall is greater than the inner diameter of the second annular protrusion 471, the second annular protrusion 471 will limit the protrusion of the tube wall, so that the protrusion of the tube wall cannot easily move to the rear end, thereby further preventing the tube wall from being separated from the rubber sleeve 47, and improving the stability of the connection between the nylon hose 48 and the rubber sleeve 47.

[0072] The arrangement of at least two second annular protrusions 471 can make the protrusion of the tube wall be at the front end of the second annular protrusion 471 and between adjacent second annular protrusions 471, thereby further increasing the limiting effect of the second annular protrusion 471, improving the anti-skid property of the rubber sleeve 47, and further improving the stability of the connection between the nylon hose 48 and the rubber sleeve 47.

[0073] In the embodiment, the elastic member 44 is a non-metallic gasket ring that can insulate and separate the conditioning plate 13 from the gland seat 41, which can effectively enhance the insulation between the conditioning plate 13 and the gland seat 41.

[0074] The principles and implementation modes of the present application are described by using specific examples in the present application, and the above-mentioned examples are only used to help understand the method and its core idea. It should be noted that, for ordinary skilled in the art, without departing from the principles of the present application, the present application can be improved and modified in several ways, and these improvements and modifications also fall within the protection scope of the claims of the present application.

Claims

1. A sensor having an out-of-plane sensitive MEMS accelerometer, characterized by, The sensor body includes a base, a collection plate and a conditioning plate, the collection plate is arranged transversely, a front surface is attached to a front end surface of an inner cavity of the base, and a rear surface is attached to a surface-out sensitive MEMS accelerometer, the conditioning plate is arranged longitudinally, and a front end is abutted to a rear surface of the collection plate, the collection plate and the conditioning plate are electrically connected through a flexible circuit board, the cable extends into the conditioning plate from a rear end of the sensor body, and the cable locking mechanism includes a gland seat, a gland and a sealing ring, the gland seat is attached to an inner wall of the base and abuts to a rear end of the conditioning plate to press the collection plate against the front end surface of the inner cavity of the base, the gland seat is provided with a through hole, the sealing ring is sleeved on an outer periphery of the cable and arranged in the through hole, and the gland is arranged in the through hole to press the sealing ring against the cable.

2. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 1, wherein, An elastic member is arranged between the gland seat and the conditioning plate, the elastic member is provided with a wire passing hole for the cable to pass through, and the gland seat presses the conditioning plate through the elastic member.

3. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 1, wherein, The conditioning plate is fixed on the collection plate in a mortise and tenon manner, the collection plate and the conditioning plate each have N layers, M layers of the N layers are flexible layers, and the M flexible layers are connected in one-to-one correspondence with corresponding layers of the flexible circuit board, wherein M and N are positive integers, respectively representing the number of layers of the flexible circuit board and the collection plate and the conditioning plate, and M≤N.

4. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 3, wherein, The conditioning plate is fixed on the collection plate in a mortise and tenon manner, specifically, the collection plate is provided with a groove, the conditioning plate is fixed on the collection plate through the groove, and the collection plate is provided with a first groove and a second groove; the conditioning plate is provided with a first connecting end and a second connecting end, the first connecting end is inserted into the first groove, and the second connecting end is inserted into the second groove. The first connecting end has an L-shaped structure in the thickness direction for matching the first groove, and the second connecting end has an L-shaped structure in the length direction for matching the second groove. Alternatively, the first connecting end has an L-shaped structure in the length direction for matching the first groove, and the second connecting end has an L-shaped structure in the length direction for matching the second groove. Further comprising a stress isolation cover arranged on the accelerometer for isolating the accelerometer from the stress of the filling glue in the inner cavity of the base.

5. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 1, wherein, A first groove is arranged in a middle part of a front end of the conditioning plate for avoiding the accelerometer, and a second groove is arranged in a middle part of a rear end of the conditioning plate for avoiding the cable.

6. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 1, wherein, An outer side surface of a front end of an inner cavity of the base corresponding to the collection plate is an annular conical surface, so that the vibration impact signal generated by the measured device is transmitted to the front end surface of the inner cavity through the annular conical surface on the base, a threaded stud is arranged at a front end of the base for rigidly mounting the sensor body on the measured device, the sensor body further comprises a temperature sensitive device, a temperature sensitive device accommodating cavity is arranged in the threaded stud and communicates with the inner cavity, and the temperature sensitive device is accommodated in the temperature sensitive device accommodating cavity and electrically connected with the collection plate.

7. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 1, wherein, ​ 8. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 7, wherein, The front end of the conditioning plate is provided with a clearance cut edge for allowing the annular conical surface to be positioned.

9. The sensor with an out-of-plane sensitive MEMS accelerometer of claim 1, wherein, The front end of the pressing cover is sleeved with the outer periphery of the sealing ring to press the sealing ring against the outer periphery of the cable, the rear end of the pressing cover is used to be sleeved with the outer periphery of the cable, a wire protection spring is arranged between the pressing cover and the cable, the front end of the wire protection spring is arranged between the pressing cover and the sealing ring, and the rear end of the wire protection spring extends along the rear end of the pressing cover; the through hole of the pressing cover seat is a stepped through hole, the stepped through hole comprises a first annular stepped surface and a second annular stepped surface arranged on the inner periphery of the stepped through hole, the first annular stepped surface is arranged on the front side of the second annular stepped surface, the outer diameter of the first annular stepped surface is equal to the inner diameter of the second annular stepped surface, the sealing ring is arranged on the first annular stepped surface, and the pressing cover is arranged on the second annular stepped surface; the outer side of the pressing cover is provided with a nylon hose and a pressing mechanism for locking the nylon hose, the pressing mechanism comprises a cap and a rubber sleeve arranged on the inner wall of the cap; the cap is arranged on the inner wall of the pressing cover seat; the inner periphery of the through hole of the pressing cover seat is provided with a third annular stepped surface, the third annular stepped surface is arranged on the rear side of the second stepped surface, and the outer diameter of the second stepped surface is equal to the inner diameter of the third annular stepped surface; the cap is arranged on the third stepped surface; the rear end of the pressing cover seat is flush with the rear end of the cap, so as to be flush with the rear end of the sensor base; the inner wall of the base is provided with a stepped surface for placing the pressing cover seat.

10. The sensor with an out-of-plane sensitive MEMS accelerometer according to claim 9, characterized in that, The inner wall of the rear end of the cap is provided with an annular barb for extruding the rubber sleeve; the inner wall of the rubber sleeve is provided with at least one second annular protrusion for cooperating with the nylon hose; when the number of the second annular protrusions is greater than one, all the second annular protrusions are arranged in sequence along the axial direction of the rubber sleeve.

11. The sensor with an out-of-plane sensitive MEMS accelerometer according to claim 2, characterized in that, The elastic member is made of insulating material, and is used to insulate and separate the conditioning plate and the pressing cover seat. The elastic member is made of insulating material, and is used to insulate and separate the conditioning plate and the pressing cover seat.

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