JPS59178383A - Magnetic access detector - Google Patents

Abstract

PURPOSE:To secure a stable detecting operation for a long time with all of component parts fixed in the arrangement by detecting changes in a magnetic flux depending on an electromotive force generated in a coil when a mobile magnetic body approaches a gap in a magnetic path member. CONSTITUTION:A magnetic flux phi is generated in a magnetic path member 2 with a permanent magnet 1. As a mobile magnetic body 7 is inserted into a gap 3 or amply approach it, the magnetic resistance of a magnetic path adapter 2A decrease to increase the magnetic flux phi in the magnetic path 2. In interlinkage with the change in the magnetic flux, a coil 4 generate a positive pulse to allow the detection of an access of the mobile magnetic body 7, namely, a mobile member 5. When the mobile member 5 approaching is separated from the gap 3, the magnetic flux phi in the magnetic path 2 decrease and a pulse in the opposite polarity is generated in the coil 4 thereby enabling detection of the separation of the mobile member 5.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic proximity detector, and more particularly to a proximity detector that utilizes the fact that the magnetic flux formed by a permanent magnet changes with the proximity of a magnetic body.

Conventional Technique 11 With the recent development of automatic control, especially robot technology, the need to reliably detect the proximity of moving mechanical elements is increasing. Conventionally, in order to detect the proximity of an object, methods using an electrical proximity switch, methods using changes in physical components such as electricity and magnetism caused by iJf moving coils and other moving elements have been used. However, devices using a proximity switch inevitably have drawbacks such as the risk of malfunction due to contact deterioration and a limited lifespan. On the other hand, those that utilize changes in physical parts have the disadvantage of having a complicated structure.

In addition, in order to monitor and control six types of events, especially for monitoring and controlling multiple correlated phenomena, at least two different types of
It is often necessary to detect the occurrence of an event. Conventionally, 2
Horn! Two detectors are used to detect the occurrence of jS-elements, which has the disadvantage that the measurement equipment becomes complicated.

OBJECTS OF THE INVENTION Accordingly, one object of the present invention is to provide a magnetic proximity detector which overcomes the above-mentioned drawbacks of the prior art.

In order to achieve the objective of ``Structure 1 of the Invention 1'', in the present invention, a permanent magnet is connected to a magnetic path member having a gap, a magnetic flux is formed within the C magnetic path member, and changes in the magnetic flux and interlinkage are The coils are arranged so that the magnetic flux changes when the movable magnetic body approaches the air gap, and the change in magnetic flux is detected by the repulsive force generated in the 17th coil.

When detecting proximity due to rotational pressure, 1-i+J
The dynamic magnetic body is configured to rotate in conjunction with the rotational movement, and the first movable magnetic body and the -1 magnetic path member are appropriately coupled, so that the space between the first and second movable magnetic bodies is The magnetic path member may be formed by opposing surfaces of the magnetic path member and the magnetic path member.

Two events, for example, the application of an electric value to drive the i+1 moving magnetic body and the approach of the moving magnetic body to a desired position, etc.
For detection with a detector, the present invention also provides a magnetic detector with two output coils. That is, a human-powered coil is wound around a part of a magnetic path member forming a closed magnetic path, and permanent magnets are attached at two points of the L magnetic path member such that the magnetic path member is divided into a part where the input coil is located and another part. are coupled through a gap, and a detector is constructed by providing a movable magnetic body that can freely approach the gap, and 1 - an output coil is provided in each of the leg rigid parts, and a movable magnetic body is provided in the above gap so that an One detector detects two events, and an event related to the movable magnetic body, and the detection results are taken out from the L input coil.

Embodiment In FIGS. 1 and 2, which schematically show an embodiment of the invention, a permanent magnet 1 is connected in series to a magnetic path member 2. FIG.

The magnetic path member 2 of this embodiment includes a magnetic path adapter 2A having an air gap 3. The coil 4 is provided so as to interlink with the magnetic flux change in the magnetic path member 2. This coil 4 is sufficient to be interlinked with the above magnetic flux change, and the number of turns may be one.

A movable magnetic body 7 is attached to a part of the movable member 6 whose proximity is to be detected using an adhesive 6, and the movable magnetic body is made to face the gap 3 described in 1-. When the movable member 5 itself is a magnetic material, a separate +
It is clear that the +f dynamic magnetic body 7 is not required. A holding member 8 shown in FIG. 2 holds the permanent magnet 1, magnetic path member 2, and magnetic path adapter 2A together.

In the embodiment shown in FIG. 3, the magnetic path member 2 is composed of a movable portion 2B, a fixed portion 2D having a long groove 2C, and a contact portion 2E. One end of the arm 9 that holds the movable part 2B of the magnetic path member 2 is pivoted by a pin 10, and the end of the arm 9 (1r) is fitted into the L leg long groove 2C, and the other end is connected to the 8i part 2E with a gap. 3. The armature portion 2E of the magnetic path member 2 is provided with a coil 4 so as to interlink with the magnetic flux change in the magnetic path member 2. Preferably, the movable portion 2B of the magnetic path member 2 is covered with a coil 4. It is operatively coupled to a sensing element, such as a rotating arm member (not shown) of a Roht.

FIG. 4 schematically shows an embodiment for detecting both electrical and mechanical inputs. An input coil 11 is inserted into the - section of the magnetic path member 2 forming a closed magnetic path. A permanent magnet 1 is connected through a gap 3 between two points X1 and X2 such that the magnetic path member 2 is divided into two parts, a part 2F where the human-powered coil 11 is located and another part 2G. In the illustrated example, 1- a magnetic path adapter 2A is inserted between the closed magnetic path of the magnetic path member 2 and the permanent magnet 1;
A gap 3 is formed in this magnetic path adapter 2A. A first output coil 4A is wound around a certain portion 2F of the magnetic path member 2, and a second human-powered coil 4B is wound around the other portion 2G of the magnetic path member 2. A movable member 5 shown in FIG. 1B faces the gap 3 in a freely accessible manner.

)--The operation of the magnetic detector according to the present invention having the above configuration will be explained. In the embodiment shown in FIG. 1, the permanent stone resistant l generates a magnetic flux Φ in the magnetic path member 2.

The movable magnetic body 7 that is in contact with the movable member 5 is iβ in the gap 3.
; When someone approaches or approaches 1 minute, the magnetic path adapter 2A
The magnetic resistance in the magnetic path 2 decreases, and the magnetic flux Φ in the magnetic path 2 increases. The coil 4 interlinks with this change in magnetic flux when the magnetic flux increases, and generates a positive pulse shown, for example, at the 51st Δp1. By generating this pulse p1, the approach 1p of the movable magnetic body 7, that is, the approach of the movable member 5, is detected. On the contrary, ['' When the approaching movable member 5 leaves the gap 3, the magnetic resistance of the magnetic path attachment 2A increases and the magnetic flux Φ in the magnetic path 2 decreases.
The pulse p in Fig. 5 is applied to the coil 4 (o) with the opposite polarity to that when the magnetic flux increases.

occurs. By the generation of this pulse P2, detachment of the Ilf dynamic magnetic body, that is, detachment of the movable member 5 is detected.

In the embodiment shown in FIG. 3, the rif movement 8 movement 8 minutes 2B of the magnetic path member 2 is linked to the rotating arm of the robot (not shown in FIG. 4), and this 1i (moving part 2B reaches a predetermined position The setting is made so that the gap 3 becomes sufficiently narrow when the magnetic flux Φ of the magnetic path member 2 increases.
When the f moving part 2B approaches and leaves the polarized part 2E,
For example, the coil 4 (not shown in FIG. 5) receives pulses I)1. P2
occurs, and its approach/departure is detected. Pulse P1.
It is clear to those skilled in the art that the polarity and υ waveform of p2 are determined by the specifications of the permanent magnet 1 and the coil 4.

In the embodiment shown in FIG. 4, assuming that the direction of the magnetic flux Φl in the magnetic path member 2 due to the current in the direction of the arrow i in the input coil 11 is one direction, referring to the solid line in FIG. 6, the magnetization curve is A permanent magnet 1 is installed in the magnetic path section 2F where the input coil 11 is located.
Let B be the magnetic flux density of the magnetic flux Φ generated by the magnetic path member 2
If the magnetomotive force acting on the closed magnetic path is H, then the magnetic flux density generated in the other magnetic path member 2G by the permanent magnet 1 can be expressed as -B. Magnetic flux increment Φ that occurs in the magnetic path section 2F where the human-powered coil 11 is located when the movable magnetic body 7 approaches the gap 3
Assuming that the direction of □ is the stopping direction, the magnetic flux increment generated in the other magnetic path portion 2G of 1-2 when the movable magnetic body 7 approaches the gap 3 is 1Φ in the negative direction. becomes.

The magnetization characteristic of the magnetic path member 2 has a hysteresis characteristic as shown by the chain line in FIG. The change in magnetic flux can be approximately represented by the change in magnetic flux in the case of the magnetization curve shown by the solid line in Figure 6, that is, the magnetization curve passing through the point where the magnetomotive force H = 0 and the magnetic flux density B = O. Since this can be done, the explanation will be given below with reference to the solid line in FIG.

At time 1 = 1 o, if the human-powered coil 11 approaches the dynamic magnetic gap 3 at 1:1 of the line f1 with no current, then the force acts on the magnetic path member 2 as shown in FIG. The magnetomotive force H increases by +ΔH as the magnetic resistance of the gap 3 decreases. At this time, the magnetic path section 2 with the human-powered coil l]
At F, this magnetomotive force increment +△I (Ji, and the magnetic flux density is +△B from point P to point P according to the differential permeability at point P, which is opposite to the magnetic flux density B of the solid line magnetization 1111). According to the magnetic flux change corresponding to this magnetic flux density increment, a pulse +1, for example, schematically shown in FIG. 7A is generated in the first output coil 4A. Although the actual pulse has a more complex waveform than that shown in No. 7A1A, here: ii: Since a sexual comparative explanation is sufficient, a rectangular pulse is assumed for convenience. At the same time, -2 other magnetic path parts 2G
In this case, the magnetic flux density -B is the solid line 1. in FIG. point Q empty point Q
2, and a reverse polarity pulse -1 as shown in FIG. 7A, for example, is generated in the second output coil 4B. Therefore, the approach of the movable magnetic body 7, that is, the approach of the movable member 5, can be detected by noting the simultaneous occurrence of opposite polarity pulses in both output coils 4A, 4B. The movable magnetic body 7 is 1
It is clear that when the heel 11ia is released from the gap 3, the pulse polarity in FIG. 7A is reversed.

Finally, time 1=1. Under the condition that the movable magnetic body 7 is separated from the gap 3, the input coil 11 has an arrow ITIJ
When the input current flows in the direction of i, the magnitude of the current increases the magnetomotive force increment in the magnetic path section 2F where the input coil 11 is located by +Δ
If it is such as H, the magnetic path portion 2F
The magnetic flux density increases by +ΔB from point P to point P in FIG. 6, and therefore, a pulse +1 as shown in FIG. 7B, for example, is generated in the negative current output coil 4A. At the same time, in the magnetic path portion 2G on the above side, the magnetic flux density B increases by one point ΔB from point Q to point Q+ in FIG. occurs.

Therefore, by noting the simultaneous occurrence of pulses of the same polarity in both output coils 4A and 4B, it is possible to detect the application of the input terminal to the human-powered coil 11. It is clear that when the orientation of the input terminals is reversed, the polarity of the pulses in Figure 7B are reversed.

Furthermore, the approach of the movable magnetic body 7 to the gap 3 and the human-powered coil 1
If the application of 1 to 1 and the input terminal occurs simultaneously, the magnetomotive force will be +2△H in the magnetic path section 2F where the human coil is located.
The magnetic flux density increases by +2ΔB, and a pulse +2 as shown in FIG. 7C, for example, is generated in the first output coil 4A. At the same time, in the I-bending/extending magnetic path portion 2G, the magnetic flux density increases by, for example, +ΔB from point Q in FIG. No change occurs, and the second output coil 4B receives, for example, 1=t9. as shown in FIG. 7C.
No pulse is generated. Therefore, the first output coil 4A
By noting the simultaneous occurrence of the presence of pulse +2 at and the absence of pulse at the second output coil 4B,
tj) It is possible to detect the simultaneous occurrence of the approach of the dynamic magnetic body 7 to the gap 3 and the application of the input terminal to the input coil 11. It is clear that the polarity of the pulse in FIG. 7C is reversed when the 1Qli theory of the movable magnetic body 7 and the interruption of the input current occur simultaneously [7].

Table 1 shows the input and outputs of both output coils 4A and 4B when the movable magnetic body 7 approaches the gap 3 using mechanical force and when the application of the input terminals to the coils 1 to 11 is electrically terminated. Indicates the relationship between As is clear from the table, according to the present invention, logical sum processing and logical product processing can be performed on mechanical input and electrical input using a detector having an extremely simple structure. It is also possible to monitor the response speed of the device by detecting the time difference between electrical input and mechanical input.

In the explanation from Table 1 onwards, it was assumed that the magnetomotive force change ΔH due to the input current of the input coil 11 was equal to the magnetomotive force change ΔH due to the proximity of the movable magnetic body 7 to the air gap 3. They do not necessarily have to be equal, and it is sufficient if they generate a change that can be detected in the output pulses of the output coils 4A and 4B.

Effects of the Invention 1 - Effects of the magnetic detector according to the present invention described above are listed below.

(a) Since all components other than the object to be detected are fixedly arranged, it is possible to have a robust structure and ensure stable detection operation over a long period of time.

(b) Since proximity is detected using the gap provided in the magnetic path member, it is possible to detect not only approach from one direction but also approach from various directions toward this gap and interlocking movement passing through this gap. can.

(c) Since the output is a pulse, it can be easily incorporated into a control device using a computer.

(d) Since the magnetic flux that constantly acts on the detection coil is formed by a permanent magnet and no excitation coil is used, power consumption is extremely low.

(e) For peace of mind, electrical human power and mechanical input can be detected individually with a single detector with a simple structure, and internal inputs can be subjected to logical product processing and logical sum processing.

[Brief explanation of the drawing]

Fig. fiIJ1 is a plan view of one embodiment of the present invention, Fig. 2 is a cross-sectional view taken along line I-II I in Fig. 1, Figs. 3 and 4 are explanatory diagrams of other embodiments, and Fig. 5 , Figures 6 and 7A
-7C is an explanatory diagram of the operation. 1... Permanent magnet, 2... Magnetic path member, 3...
・Air gap, 4...Coil, 4A...First output coil, 4B...Second output coil 7...Movable magnetic body, 11...Human coil special engineering 1 applicant Shin Takei r゛Special;1
Application agent: Patent attorney Tsugube Ichito, 31□
Figure 3 Figure 6 Figure 7A Figure 7B ■ 7C1 Foot 1 Y. i, i, L48"■--ka2

Claims (3)

[Claims] (1) A magnetic path connected in series to the magnetomotive force of a permanent magnet,
1. A gap formed in the magnetic path member in series with the magnetomotive force, 1-
A coil provided so as to interlink with the magnetic flux change in the Ie path section, and 1. A magnetic proximity detector comprising a movable magnetic body that can freely approach a gap. (2) The proximity detector according to claim 1, wherein: (1) a deep groove formed in one end face of the magnetic path member (1) facing the gap; An arm is provided for pivotally supporting the movable magnetic body, and -1, one end of the movable magnetic body is loosely fitted into the deep groove, and the other end of the movable magnetic body is connected to the magnetic path member. A magnetic proximity detector formed by opposing the other of the air gap opposing it'+i. (3) Magnetic path members forming a closed magnetic path, 1: Input coil wound around magnetic path part phase 1-; A permanent magnet magnetically coupled via an air gap between two points of the magnetic path member 1, such as dividing the magnetic path member 1, and a first output wound around a portion of the magnetic path member where the input coil is located. Coil, parallel 1. A magnetic proximity detector comprising a second output coil wound around the other part of the closed magnetic path.