CN2083740U

CN2083740U - Magnetic displacement transducer

Info

Publication number: CN2083740U
Application number: CN 91201112
Authority: CN
Inventors: 赵阳; 凌保明; 唐琼; 陈大军
Original assignee: GAOLIAN SENSING TECHNOLOGY Co HANGZHOU
Current assignee: GAOLIAN SENSING TECHNOLOGY Co HANGZHOU
Priority date: 1991-01-18
Filing date: 1991-01-18
Publication date: 1991-08-28

Abstract

The utility model relates to a magnetic effect displacement transducer, which uses the action of a movable axial permanent magnetic field and an axial pulse magnetic field formed by electric current pulses in a waveguide tube to vitalize the torsion oscillation of the waveguide tube, and then the oscillation echo is received by a magnetoelectric sensor, the displacement of an object which is measured and drives the motion of a permanent magnet can be measured by measuring the period of the echo and emission electric current pulses. The magnetic effect displacement transducer has compact structure and easy installation. The magnetic effect displacement transducer is indicated by analog digitals The utility model has the advantages of large displacement range from submillimetre to thousands millimetre for measuring, unlimited resolution, better linearity and repeatability, high precision, anti oil stain, and proof vibration. The magnetic effect displacement transducer has practical value in the measuring aspects of the displacement of the motion of the piston of a hydraulic oil cylinder, etc.

Description

Magnetic displacement transducer

The utility model belongs to the sensor that mechanical shift is carried out electrical measurement.

Utilize the magnetic effect principle to carry out the instrument of displacement measurement, existing magnetoelectricity low coverage meter is mainly used in the displacement measurement that range is a submillimeter level; The magnetic-grid-type detector for displacement measuring is used for large displacement measurement.It is made up of magnetic scale and magnetic head, and its resolution is limited by magnetic grid pitch and magnetic head structure.Volume is big, the installation requirement height.Be limited in open environment and use.But in some scientific researches and engineering field, often need measurement mechanical displacement in the sealing body, for example measurement of throw of poston in the hydraulic jack, magnetic-grid-type displacement instrument is helpless, and this type of measurement will need day by day.

Problem to be solved in the utility model provides a kind of sensor of magnetic effect detector for displacement measuring, and it can be to the displacement in the sealing body, and particularly big displacement carries signal to realize measurement.Sensor construction compactness, easy for installation, resolution is unlimited, the measuring accuracy height.

Organization plan of the present utility model:

Article one, waveguide is fixed in the mount pad of front and back end, in pipe, penetrate a lead, being provided with one outside pipe can be axially movable and produce the permanent magnet of axial permanent-magnetic field, magneto-electric induction receiver coupling in waveguide and the rear end mount pad, lead is connected with pulse-generator circuit on the printed circuit board (PCB), and the received signal that the magneto-electric induction receiver produces is transported to display device through socket.

Tens millimeters, during large displacement measurement is used more than several thousand millimeters; for making the not contaminated and mechanical damage of waveguide; one protection tube is arranged between waveguide and permanent magnet, and the protection tube rear end is fixed in the rear end mount pad of waveguide, and its front end and waveguide front end mount pad match.

Produce the magnet of axial permanent-magnetic field, structurally can adopt annular or other than ring type permanent magnet, also can adopt the parts that permanent magnet is housed on the part of annular or other than ring type.This permanent magnet or is connected and fixed with testee outside the protection tube of waveguide outside waveguide, and it just moves with the axial displacement of testee.

Description of drawings:

Fig. 1: the utility model magnetic effect displacement transducer general structure scheme synoptic diagram;

Fig. 2: I part analyses and observe enlarged diagram among Fig. 1;

Fig. 3: the enlarged drawing of II part among Fig. 1 is the enlarged diagram of waveguide and inner lead thereof;

Fig. 4: unload the inner structure synoptic diagram that shows behind the barrel shrond of rear end mount pad of waveguide among Fig. 1;

Fig. 5: Fig. 4 A-A is to cut-open view;

Fig. 6: permanent magnet is the permanent magnet block diagram that four cylindric permanent magnets are housed on ring-shaped work pieces;

Fig. 7: permanent magnet is the permanent magnet block diagram that three cylindric permanent magnets is housed having on the ring-shaped work pieces of breach;

Fig. 8: permanent magnet is the permanent magnet parts that a cuboid permanent magnet is housed on the other than ring type part.

Further specify the embodiment of technical scheme with reference to accompanying drawing.

As shown in Figure 1, waveguide 16 is arranged in protection tube 5, penetrate lead 15 in the waveguide, waveguide is fixed in the front and back ends mount pad.Blind nut 10, screw 11, lead rail cylinder 12, register pin 13 in holder 2 by Fig. 1, spring 1 and the front end mount pad shown in Figure 2 and pull and support the effect of the governor motion that part 14 forms makes waveguide be tense situation.Screw 11 is owing to be subjected to the axial restriction of blind nut 10 and lead rail cylinder 12, only can rotate and can not move axially.An axial groove is arranged pulling and supporting on the part 14, an end of register pin 13 is inserted in this groove just, and restriction pulls and supports part 14 and rotates, and only allows to move axially with the rotation of screw 11.Lead rail cylinder 12 rear ends press fit in the protection tube 5.Like this, as long as rotating screw 11 can drive and pull and support part 14 and axially move forward and backward, just can regulate the tensioning degree of waveguide 16.Rear end mount pad such as Fig. 1, Fig. 4, shown in Figure 5, by bearing 7, barrel shrond 8 and be fixed on grip block 17 on the bearing 7, rubber slab 18, screw 19, printed circuit board (PCB) 20, dielectric film 21, clamping plate 22,

printing weldering plate

23 and 24, printed circuit board (PCB) 25, dielectric film 26, supporting plate 27, rubber slab 28 is formed.

But the permanent magnet 6 of axially-movable is housed in the outside of protection tube 5, and this permanent magnet and testee are connected, and move with testee.Require permanent magnet to produce axial constant magnetic field, it structurally can be that annular permanent magnnet is shown in the part among Fig. 16; Also can be on annular nonmagnetic body, to load onto several permanent magnets, as shown in Figure 6; Figure 7 shows that to have breach on non-magnet ring body, it is convenient to mounting or dismounting; Also the acyclic body that can make of non-magnetic material is a support, permanent magnet is housed thereon produces axial permanent-magnetic field, as shown in Figure 8.

The protection tube rear end is fixedly connected on bearing 7.Waveguide 16 passes through bearing 7 and with the magneto-electric induction receiver that is installed on the bearing 7 in the protection tube 5 and is coupled, and then by clamping plate 22 and rubber slab 28 it is fixed.The magneto-electric induction receiver as shown in Figure 5, by with waveguide 16 welding or glued joint fixing waveguide band 32, skeleton 29, permanent magnet 30, coil 31 and clamping plate 17 and rubber slab 18 are formed.Clamping plate 17 and rubber slab 18 are to be used for fixing the afterbody that compresses waveguide band 32 both sides.Also be fixed and clamped at the waveguide front end by sheet rubber 3.

Pulse producer pulsed emission current on the printed circuit board (PCB) 20 and 25 through lead 15, produces the axial permanent-magnetic field interaction that the circumferential pulsed magnetic field be distributed in the waveguide and aforementioned permanent magnet 6 produce, and consequently waveguide is subjected to the pulse twisting resistance.The mechanical wave that reverses of waveguide excites the speed forwards, backwards direction propagation of place (annular permanent magnnet position) with the approximate velocity of sound from reversing.The ripple of backspace (echo) reaches the magneto-electric induction receiver in the mount pad of rear end backward.Because the mechanical wave that reverses of waveguide reaches the waveguide band, be converted into the back and forth flexible stress of waveguide band, then be converted into the variation of waveguide band magnetoconductivity, thus, induction produces frequency, the amplitude induced potential corresponding with reversing mechanical phase of wave in receiver coil 30, through socket 9 signal is transported to the displayed record device.

Because received signal (echoed signal) is relevant with the axial location of permanent magnet 6 on waveguide with the length of the cycle td of pulsed emission current, just can passes through the length of mensuration cycle td, and accurately measure this magnet position.Because of permanent magnet 6 and movable body to be measured are fixedly linked, just can realize displacement measurement thus.

The advantage of magnetic effect displacement transducer of the present utility model:

Can transmit accurately and stably the displacement signal from submillimeter level to several thousand millimeters, the linearity, good reproducibility, stability is high, and resolution ratio is unlimited in theory. Compact conformation, easy for installation. Applicability is wide, is applicable to that especially sealing carries out large displacement measurement in the body, for example is applied to the measurement, respond well of hydraulic cylinder piston displacement, has broad application prospects.

Claims

1, a kind of magnetic effect displacement transducer, it is characterized in that the waveguide [16] that two ends are fixing, a permanent magnet [6] of fixing with measured object and moving is arranged outside pipe, a lead [15] is arranged in pipe, magneto-electric induction receiver coupling in waveguide and the rear end mount pad, lead [15] is connected with pulse-generator circuit on printed circuit board (PCB) [20], [25], and the received signal that the magneto-electric induction receiver produces is exported through socket [9].

2, magnetic effect displacement transducer according to claim 1 is characterized in that the magneto-electric induction receiver is made up of the waveguide band (32) that is connected with waveguide (16), skeleton (29), permanent magnet (30), coil (31) and clamping plate (17) and rubber slab (18).

3, magnetic effect displacement transducer according to claim 1, it is characterized in that waveguide (16) front end is fixed by sheet rubber (3), the rear end is fixed by clamping plate (22) and rubber slab (28), and waveguide band (32) both sides afterbody is fixedly clamped by clamping plate (17) and rubber slab (18).

4, magnetic effect displacement transducer according to claim 1, it is characterized in that screw (11) is arranged in the waveguide front end mount pad (I), by blind nut (10), lead rail cylinder (12) axial location, screw (11) can only pull and support part (14) rotation relatively, pull and support an axial groove is arranged on the part, one end of register pin (13) is inserted in to limit in this groove and pulls and supports the part rotation, displacement before and after can only transferring axially with screw threads is by the tightness of spring (1), holder (2) adjusting waveguide (16).

5, magnetic effect displacement transducer according to claim 1; it is characterized in that between waveguide (16) and the permanent magnet (6) protection tube (5) being arranged; fixedly connected with bearing (7) in the protection tube rear end, the protection tube front end is connected with waveguide front end mount pad (I).

6,, it is characterized in that the rear end cylindrical of protection tube (5) front end endoporus and front end mount pad (I) middle guide tube (12) is press-fitted according to claim 4 or 5 described magnetic effect displacement transducers.

7, magnetic effect displacement transducer according to claim 1 or 5 is characterized in that the outer permanent magnet (6) of protection tube is an annular or other than ring type magnet, or the parts of permanent magnet is housed on annular or other than ring type part.

8, magnetic effect displacement transducer according to claim 1 or 5 is characterized in that described permanent magnet is contained on the support of the acyclic body that non-magnetic material does.