CN203323864U

CN203323864U - High-sensitivity piezoelectric vibration sensor

Info

Publication number: CN203323864U
Application number: CN201320339717XU
Authority: CN
Inventors: 栗合营; 俞梅; 朱玉芳
Original assignee: Nanjing Normal University
Current assignee: Nanjing Normal University
Priority date: 2013-06-13
Filing date: 2013-06-13
Publication date: 2013-12-04
Anticipated expiration: 2023-06-13

Abstract

The utility model provides a high-sensitivity piezoelectric vibration sensor including a weight self-unloading device and a preload balancing device. The weight self-unloading device includes a sensor pedestal, a steel ball, a support rod and an inertia mass block. The steel ball is disposed between a conical pit of a boss on the sensor pedestal and a conical pit of the lower end of the support rod. The upper end of the support rod is screwed in a threaded hole in the lower end of the inertia mass block, so that the mass block is supported by the steel board and the gravity force is not applied to a piezoelectric sheet directly. Therefore, the size of the mass block is not limited. Besides, the spring preload balancing device is arranged on a piezoelectric assembling trunk line arranged along a main force measuring direction and includes forcing screws, spring supports and a preload spring. The preload spring is pressed between the two spring supports tightly through the forcing screws. The compression volume of the preload spring can be adjusted by screwing the forcing screws. That a preload static force is applied to the piezoelectric ceramic sheet is guaranteed and the inertia mass block is disposed in the middle position in a static state. The high-sensitivity piezoelectric vibration sensor provided by the utility model is suitable for measuring main forces in the horizontal direction.

Description

The high sensitivity piezoelectric vibration pickup

Technical field

The utility model relates to a kind of high sensitivity piezoelectric vibration pickup, relates in particular to a kind of high sensitivity piezoelectric vibration pickup with piezoelectric sensing device of self-unloading gravity installation and pretightning force function, belongs to field of mechanical technique.

Background technology

The sensitivity of piezoelectric vibration pickup is one of key parameter, the mass of general piezoelectric vibration pickup directly vertically acts on piezoelectric ceramics, so the size of mass is restricted, and mass is larger, inertial force is larger, and the sensitivity of piezoelectric vibration pickup is just higher.For the tested machine measuring vibrations of difference, a main dynamometry direction is arranged in addition, general piezoelectric vibration pickup specific aim is not strong, and measurement result is not accurate enough.

Summary of the invention

The technical problems to be solved in the utility model is to provide a kind of novel piezoelectric formula vibration transducer, it has adopted the self-unloading gravity installation, mass is not acted directly on piezoelectric patches, and its gravity direction is vertical with horizontal direction master dynamometry, so the size of mass is unrestricted.Piezoelectric sensing assembly line along main dynamometry direction setting is provided with spring preloading device in addition, guarantee to have on piezoelectric ceramic piece the static force of a pretension, and making inertial mass when static state be in centre position, the utility model is applicable to measuring the main dynamometry of horizontal direction.

The technical solution of the utility model is:

The high sensitivity piezoelectric vibration pickup, comprise self-unloading gravity installation and the piezoelectric sensing device with pretightning force function, wherein the self-unloading gravity installation comprises sensor base, steel ball, pole and inertial mass, steel ball is arranged between the upper boss taper hole and pole lower end taper hole of sensor base, and makes between boss and pole a gap is arranged; The lower end of inertial mass is provided with a threaded hole, and the upper end of pole is connected with inertial mass by described threaded hole; Piezoelectric sensing device with pretightning force function comprises square steel tube housing, piezoelectric sensing device, output line, housing screw, protective cover, spring suppport and preloading spring, the square steel tube housing is welded on described sensor base, and described self-unloading gravity installation is arranged in the square steel tube housing; Preloading spring and spring suppport form the pretightning force device, and are fixed on an outside of described square steel tube housing by the first housing screw, and the end of the first housing screw screws in a side of inertial mass; The piezoelectric sensing device comprises copper backing, piezoelectric ceramic piece, insulation tube, elastomeric pad, conducting strip and the second housing screw, piezoelectric ceramic piece and conducting strip alternately join in groups successively, two copper backings lay respectively at the group two ends, wherein copper backing and elastomeric pad join, insulation tube is through in the center pit of described two copper backings, piezoelectric ceramic piece, conducting strip and elastomeric pads, be fixed on another outside of described square steel tube housing by the second housing screw, the end of the second housing screw screws in the opposite side of inertial mass again; Two protective covers are separately positioned on the outside of pretightning force device and piezoelectric sensing device, and output line is connected with conducting strip, and pass from the protective cover of that side of piezoelectric sensing device.

Sensor of the present utility model can be arranged on various precision optical machinery process equipments, as on surface grinding machine, cylindrical grinder, semiconductor silicon (germanium) slicing machines, as high-sensitivity vibration sensor, with dynamic-balance measuring system, match, rotary part to equipment carries out dynamic balancing measurement and correction, the vibration values of equipment is reduced, reach the purpose of improving the quality of products.

The accompanying drawing explanation

Fig. 1 is the front view that the utility model high sensitivity piezoelectric vibration pickup dissects along the front and back plane of symmetry.

Fig. 2 is the cut-open view of the piezoelectric vibration pickup of high sensitivity shown in Fig. 1 along the A-A line.

Embodiment

As shown in Figure 1, the high sensitivity piezoelectric vibration pickup comprises a set of self-unloading gravity installation and a set of pretension balance device, for bearing the gravity of mass, inner chamber at square steel tube housing 2, the self-unloading gravity installation is arranged on sensor base 1, sensor base 1 and 2 welding of square steel tube housing, square steel tube housing 2 tops are provided with top cover 14, pole 4 upper end threaded portions are screwed into inertial mass 6 lower end threaded holes, steel ball 3 is placed between the cone hole of pole 4 cone holes, lower end and sensor base 1 upper end, pole 4 and sensor base 1 are kept apart by steel ball 3, the gravity that this sensor mass piece produces is born by steel ball 3.Because mass does not act directly on piezoelectric patches, so mass can suitably increase in certain limit, can obviously improve the sensitivity of sensor.

Square steel tube housing 2 outer right wall are installed a described protective cover 13, in described protective cover, horizontal direction is being arranged in order a copper backing 7 from left to right, one group of piezoelectric ceramic piece 8 and 12 groups of conducting strips (between every two piezoelectric ceramics, being provided with a conducting strip 12), a copper backing 7 and an elastomeric pad 11, described piezoelectric ceramics 8, conducting strip 12, copper backing 7 and elastomeric pad 11 all are provided with center pit, an insulation tube 9 passes their center pit, and square steel tube housing 2 outer right wall circular holes, pass from right to left the hole of insulation tube by a housing screw 10 again, in the screw on the right side of screw-in mass 6, square steel tube housing 2 left side outer walls are also installed a described protective cover 13, in described protective cover, another housing screw 10 is through spring suppport 15, the center pit of preloading spring 16, in the screw in the left side of screw-in mass 6, owing to by housing screw 10, preloading spring 16 being pressed between two flat spring supports 15, turn housing screw 10 and can regulate the decrement of preloading spring 16, make to have on piezoelectric ceramic piece 8 static force of a pretension, and guarantee that inertial mass 6 is in centre position when static state.The described protective cover 13 on right side is provided with the signal wire delivery outlet, so that output line 5 passes through.

Sensor base 1 is fixedly connected with measured machine, therefore with vibration of machine, when sensor base 1 horizontal direction vibration, produced and swing by the pole 4 of steel ball supporting, connected mass 6 produces larger inertial force, by housing screw 10 and elastomeric pad 11, acts on piezoelectric ceramic piece 8, and piezoelectric ceramic piece 8 is by stressed voltage (electric charge) signal that is transformed into of institute, connect output line 5 by conducting strip 12, electrical measuring device is given in output.

Owing to thering is higher sensitivity, described piezoelectric vibration pickup is arranged on the machine of main measurement transverse vibration, by the centrifugal force that on the rotation parts, amount of unbalance produces, can be clear by the utility model sensor, accurately measure.

Claims

1. the high sensitivity piezoelectric vibration pickup, is characterized in that, comprises self-unloading gravity installation and the piezoelectric sensing device with pretightning force function, wherein,

The self-unloading gravity installation comprises sensor base (1), steel ball (3), pole (4) and inertial mass (6), steel ball (3) is arranged between the upper boss taper hole and pole (4) lower end taper hole of sensor base (1), and makes between boss and pole (4) gap is arranged; The lower end of inertial mass (6) is provided with a threaded hole, and the upper end of pole (4) is connected with inertial mass (6) by described threaded hole;

Piezoelectric sensing device with pretightning force function comprises square steel tube housing (2), piezoelectric sensing device, output line (5), housing screw (10), protective cover (13), spring suppport (15) and preloading spring (16), it is upper that square steel tube housing (2) is welded on described sensor base (1), and described self-unloading gravity installation is arranged in square steel tube housing (2), preloading spring (16) and spring suppport (15) form the pretightning force device, and are fixed on an outside of described square steel tube housing (2) by the first housing screw, and the end of the first housing screw screws in a side of inertial mass (6), the piezoelectric sensing device comprises copper backing (7), piezoelectric ceramic piece (8), insulation tube (9), elastomeric pad (11), conducting strip (12) and the second housing screw, piezoelectric ceramic piece (8) and conducting strip (12) alternately join in groups successively, two copper backings (7) lay respectively at the group two ends, wherein a copper backing (7) joins with elastomeric pad (11), insulation tube (9) is through described two copper backings, piezoelectric ceramic piece (8), conducting strip (12), and in the center pit of elastomeric pad (11), be fixed on again another outside of described square steel tube housing (2) by the second housing screw, the end of the second housing screw screws in the opposite side of inertial mass (6), two protective covers (13) are separately positioned on the outside of pretightning force device and piezoelectric sensing device, and output line (5) is connected with conducting strip (12), and passes from the protective cover of that side of piezoelectric sensing device.