JPH0733131Y2 - Non-contact type angle sensor unit and its application products - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a high-performance non-contact angle sensor unit that can be used for multiple purposes and its application product.

[Conventional technology]

The non-contact type angle sensor that combines a magnetoresistive element and a permanent magnet has zero sliding noise compared to the contact type (sliding type) and is superior in durability and explosion proof. It is widely used for various purposes, and various structures have been proposed according to the application.

15 to 19 show an example of a conventional general-purpose angle sensor. This angle sensor has a bearing member at the center of the lid 1.
A shaft 4 rotatably supported via 2, 2, a permanent magnet 3 attached to the inner end of the shaft 4, and a magnetoresistive element arranged concentrically with the shaft 4 and close to the permanent magnet 3. The magnetoresistive element portion 5 is fixed to the central portion of the main body 6 coupled to the lid 1.

In addition, 7 is a screw for attaching the sensor to a fixing portion (not shown), 8, 9 and 10 are terminal plates, 11 is a casing, and 12, 13, 14 are terminals led from the terminal plates 8, 9 and 10. When a part to be measured (not shown) rotates the shaft 4, the magnetoresistive element part 5 outputs a voltage corresponding to the angular displacement of the shaft 4, and the output voltage is displayed on a meter (not shown).

20 and 21 show an example of a conventional inclinometer,
This inclinometer is a closed container 15 containing damping oil.
And a gate-shaped hanging plate 17 that is swingably hung inside the closed container 15 via pins 16 and 16, and a pair of permanent magnets 18 and 18 attached to the inside of the hanging plate 17, Permanent magnet 18,
The mounting plate 2 is composed of magnetoresistive element portions 5a, 5a, etc. mounted on the lower part of the mounting plate 20 so as to face one of the 18
The top of 0 is fixed to the lower surface of the lid 19.

Incidentally, 21 and 21 in the figure are terminals led from the magnetoresistive element portions 5a and 5a, and when the closed container 15 is tilted by the tilting operation of the DUT (not shown), the hanging plate 17 pulls the pins 16 and 16. As a fulcrum, it relatively swings in the direction of arrow a, the magnetoresistive element section outputs a voltage corresponding to the inclination angle of the hanging plate 17, and this output voltage is displayed on a meter (not shown).

[Problems to be Solved by the Invention] However, the conventional angle sensor has the following problems.

[I] The angle sensor or inclinometer, etc., has a completely different structure of the sensor each time the application is different, so the basic performance and quality of the product will be uneven, and in preparation for the customer's order, Since it is necessary to stock various types of parts, it is inconvenient in terms of production management.

[Ii] Since the angle sensor shown in FIG. 15 is equipped with only one permanent magnet 3, the magnetic flux density acting on the magnetoresistive element 5a is small, and when an unreasonable load is applied to the shaft 4, The magnetic flux distribution fluctuates. Therefore, the output sensitivity of the sensor is low, and the temperature characteristics are insufficient.

In view of the above-mentioned problems, the present invention provides an angle sensor unit that can be used for various purposes as an angle sensor for various purposes and has good performance, and also provides various products to which the angle sensor unit is applied. Is an issue.

[Means for Solving the Problems]

In order to solve the above problems, the present invention comprises the following four means.

1. A non-contact type angle sensor unit that measures the angle of the yoke that rotates in conjunction with the object to be measured. A yoke to which permanent magnets are attached opposite to each other and a large number of magnetoresistive elements are laminated on a concentric circle composed of a plurality of magnets, and they are formed so as to form two axisymmetric element parts on both sides of the diameter of the concentric circle. And the like are connected in series, and the yoke is supported by the main body so as to rotate within a predetermined angle range through bearings provided at both ends of the yoke. The element portion is fixed to the main body so as to be concentric with the rotation axis of the yoke and close to the permanent magnet so as to be interposed between the pair of permanent magnets, and when the yoke is at the middle angular position, The magnetic flux generated from the permanent magnet is One non-contact type angle sensor unit, wherein the pair of permanent magnets to the formation at each end of the yoke to be about to cross and equally in half of the element portion.

2. A yoke made by bending an elongated plate-like member having magnetic permeability and having a pair of permanent magnets attached opposite to each other inside both ends, and a large number of magnetoresistive elements laminated on a concentric circle composed of a plurality of layers. And a magnetoresistive element portion in which they are connected in series so as to form two element portions that are line-symmetrical on both sides of the diameter of the concentric circle, and the yoke is a bearing provided at both ends thereof. Is supported by the main body so as to be rotated within a predetermined angle range via, and the magnetoresistive element portion is located between the pair of permanent magnets in a state of being concentric with the rotation axis of the yoke and being close to the permanent magnets. Is fixed to the main body so that the magnetic flux generated from each permanent magnet intersects approximately half and evenly of the two element portions when the yoke is in the middle angular position. A pair of permanent magnets on each end of the yoke A non-contact type angle sensor formed of a strip-shaped driving member attached to the outside of the yoke and having an acute angled portion at its tip, a casing fixed to the main body so as to surround the driving member and the yoke, and a yoke. A plate shape provided with a drive shaft that is rotatably supported by the casing so as to be concentric with the rotation axis of the drive shaft, and an engaging portion that is fixed to the tip end portion of the drive shaft and that engages with an acute angle portion of the drive member. The general-purpose angle sensor, characterized in that the acute angle portion of the drive member engages with the engaging portion in a state where the elastic member is elastically deformed.

3. A yoke made by curving a long and thin plate-like member having magnetic permeability and having a pair of permanent magnets mounted inside each end opposite to each other, and a large number of magnetoresistive elements stacked on a concentric circle composed of a plurality of layers. And a magnetoresistive element portion in which they are connected in series so as to form two element portions that are line-symmetrical on both sides of the diameter of the concentric circle, and the yoke is a bearing provided at both ends thereof. Is supported by the main body so as to be rotated within a predetermined angle range via, and the magnetoresistive element portion is located between the pair of permanent magnets in a state of being concentric with the rotation axis of the yoke and being close to the permanent magnets. Is fixed to the main body so that the magnetic flux generated from each permanent magnet intersects approximately half and evenly of the two element portions when the yoke is in the middle angular position. A pair of permanent magnets on each end of the yoke A non-contact type angle sensor formed by bending a metal strip into a substantially L shape, having a mounting portion and a rising portion, and providing a driving member having a slit at the tip of the rising portion. The driving member is attached to the outside of the yoke via the attaching portion so that the rising portion projects to the outside of the yoke,
The main body of the angle sensor unit is fixed to the fixed portion so that the yoke stands upright in the vertical plane when the yoke is in the middle angular position, and the slit of the driving member is displaced horizontally to be measured. Angle sensor for light torque, characterized by being fitted to the pin of the object.

4. A long and thin plate-shaped member having magnetic permeability is formed by bending, and a pair of permanent magnets are attached to the inside of both ends opposite to each other, and a large number of magnetoresistive elements are laminated on a concentric circle. And a magnetoresistive element portion in which they are connected in series so as to form two element portions that are line-symmetrical on both sides of the diameter of the concentric circle, and the yoke is a bearing provided at both ends thereof. Is supported by the main body so as to be rotated within a predetermined angle range via, and the magnetoresistive element portion is located between the pair of permanent magnets in a state of being concentric with the rotation axis of the yoke and being close to the permanent magnets. Is fixed to the main body so that the magnetic flux generated from each permanent magnet intersects approximately half and evenly of the two element portions when the yoke is in the middle angular position. A pair of permanent magnets on each end of the yoke An inclinometer made up of: a weight attached to the outside of a yoke via a suspending member; and a casing enclosing the yoke and the weight so as to be swingable and containing damping oil inside, The main body of the inclinometer is attached to the fixed portion so that the yoke is in the middle angular position when the yoke and the weight are suspended in the vertical plane.

[Action]

[I] Since the magnetoresistive element portion is interposed between the magnetic poles of the pair of permanent magnets attached to the yoke, the magnetoresistive element portion has a large magnetic flux density and operates in a stable magnetic circuit. Therefore, it is possible to provide an angle sensor unit having high output sensitivity and good temperature characteristics.

[Ii] By attaching a drive member to the yoke and transmitting the movement of the object to be measured to the yoke via the drive member, it is possible to easily provide an angle sensor for various applications.

[Iii] As described in [ii], since various sensors share the angle sensor unit, the basic performance and quality of the sensor are made uniform, and the types of parts to be stocked for each product are The production system can be rationalized because it drastically decreases.

[Iv] A general-purpose angle sensor using this angle sensor unit is provided with an engaging portion on an elastic member fixed to a drive shaft, and further, an acute angle portion is provided at the tip of the drive member attached to the yoke, and the acute angle portion is engaged with the engaging portion. Since it is engaged with the joint, backlash does not occur between the drive member and the elastic member. Therefore, the angular displacement of the drive shaft can be accurately transmitted to the yoke, and the measurement accuracy is improved.

[V] In the angle sensor for light torque using this angle sensor unit, the driving member is attached to the yoke, and the tip of the driving member can be driven while the yoke is erected in the vertical plane. It is possible to accurately detect a weak movement of an object.

[Vi] Since the inclinometer using this angle sensor unit grasps the inclination angle of the weight as the rotation angle of the yoke, the inclination angle of the object to be measured can be accurately detected.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings. First
1 to 6 show an embodiment of the present invention, the main part of the present invention is a U-shaped yoke 31 made of magnetically permeable material.
And a pair of permanent magnets 32, 32 attached to the insides of both ends of the yoke 31 so as to face each other, and a large number of magnetoresistive elements (not shown) as shown in FIG. Formed of a magnetoresistive element portion 33, a synthetic resin main body 34, etc., and the yoke 31 has shafts 35, 35 protruding outward from both ends thereof.
Further, it is rotatably supported by the main body 34 via bearing members 36, 36 fitted onto the shafts 35, 35. The rotation range α of the yoke 31
Is regulated to about 120 degrees by the walls 37, 37 provided on the main body 34, and as will be described later, the output voltage changes substantially linearly within the rotation range α (Fig. 6). reference).

As shown in FIG. 5, the magnetoresistive element part 33 is composed of two element parts 33a and 33b arranged in a semicircular shape, and its input terminals 38 and 39 are provided.
And the intermediate terminal 40 are respectively connected to the terminal plates 43, 42, 44, and the magnetoresistive element section 33 is connected via the terminal plates 42, 43, 44.
The center 45 is supported by the main body 34 so as to be concentric with the rotation axis 46 of the yoke 31. Then, three terminals 47, 48, 49 led from the ends of the terminal plates 42, 43, 44 penetrate the main body 34 and project outward.

As shown in FIG. 1, the end faces (pole faces) of the permanent magnets 32, 32 are close to the upper surface of the magnetoresistive element part 33 and the lower surfaces of the terminal plates 42, 43, 44. Further, its cross section forms a rectangle as shown in FIG. 4 to cover half of the magnetoresistive element portion 33, and when the yoke 31 is at the angular position in the middle of the rotation range α, the magnetic force lines are semicircular. The element portions 33a and 33b of the above are evenly penetrated.

Note that the yoke 31 may be formed in a desired shape such as a U shape or an arc shape instead of forming the U shape, and the permanent magnets 32, 32 may be formed.
Instead of forming a rectangular cross section, it may be semicircular.

Next, the operating principle and operation of this angle sensor unit will be described. When the input voltage E is applied between the input terminals 38 and 39, the output voltage e between the terminals 38 and 40 changes as shown in FIG.

Referring to FIG. 6 in detail, in FIG. 6A, since the permanent magnet 32 is on the element portion 33b side, the resistance value (Ra) of the element portion 33a is smaller than the resistance value (Rb) of the element portion 33b. <E, the output voltage ratio is small.

Next, when the angle of the yoke 31 (see FIG. 3) is turned clockwise to bring the permanent magnet 32 to the position B, the magnetic field is generated in the element portion 33.
Evenly applied to a and 33b, Ra = Rb, e = 1/2 · E
Becomes That is, the output voltage ratio becomes 50%.

Similarly, in C, since Ra> Rb, e increases and the output voltage ratio increases.

In this way, when a DC voltage is applied between the terminals 38 and 39 and the yoke is rotated, an output voltage e close to a positive strong wave is obtained from the terminals 38 and 40 as shown in FIG.

As described above, since the pair of permanent magnets 32, 32 are attached inside the both ends of the yoke 31, a closed magnetic circuit is formed and a strong magnetic field is formed between the magnetic poles.

Therefore, the temperature characteristic is good, and when the yoke 31 rotates, the output voltage (see FIG. 6) changes steeply, so the output sensitivity is large.

Next, a general-purpose angle sensor using this angle sensor unit will be described. This angle sensor is shown in Figs.
As shown in FIG. 10, the angle sensor unit described above, a casing 52 that rotatably surrounds the yoke 31 of the angle sensor unit, and a bearing member 5 at the center of the casing 52.
A drive shaft 54 rotatably supported via 3, 53, a highly elastic plate member 55 fixed to the inner end of the drive shaft 54, and a strip-shaped drive member 56 fixed to the outside of the yoke 31. Etc.

An acute angle portion 57 is formed at one end of the drive member 56, and the acute angle portion 57 is a notch provided on the outer periphery of the plate member 55.
The plate member 55 is engaged with the plate member 58 in a state of being elastically deformed to the left in the drawing.

According to this engagement structure, backlash does not occur between the acute angle portion 57 and the notch 58, so that the angular displacement of the drive shaft 54 can be accurately transmitted. According to the above-mentioned engagement structure,
Even if an undesired external force is applied to the drive shaft 54 by a measured part (not shown), the deformation of the drive shaft 54 is absorbed by the deformation of the plate member 55, so that the angular displacement can be accurately transmitted.

In the figure, 59 is a screw part for attaching the angle sensor to a fixing part (not shown), and 60 is a stopper for restricting the rotation angle of the yoke to a small range (about 100 degrees) via the plate member 55. This is a set screw that fixes the main body 34 to the casing 52 while it is finished.

Next, an angle sensor for light torque using this angle sensor unit will be described. As shown in FIGS. 11 to 12, this angle sensor has the same structure as the angle sensor unit described above (all the same except that the terminals are taken out as three cables 62, 63, 64). , A casing 65 that rotatably surrounds the yoke 31, and a mounting hardware 67 that is mounted on the rear side of the main body 34 via a push bolt 66.
And a driving member 56a fixed to the outside of the yoke 31.

The driving member 56a has a mounting portion 56b and a rising portion 56c formed by bending a metal strip into a substantially L shape as shown in the drawing. An object to be measured (not shown) is formed at the tip of the rising portion 56c. A slit 68 for interlocking with the pin 71 from is provided. In the figure, 69 is a set screw for fixing the casing 65 to the main body 34, and 70, 70 are bolt holes for fixing the mounting hardware 67 fixed to the main body 34 to a fixing portion (not shown).

When using this angle sensor, the yoke 31 and the drive member 56
Drive member 56a so that a stands upright in the vertical plane.
The tip end of the main body 34 is locked to the object to be measured, the posture of the main body 34 is adjusted so that the yoke 31 divides the turning range α into approximately two equal parts, and then the mounting hardware 67 is fixed to the fixing portion.

In this state, the driving force for driving the tip of the drive member 56a is minimal (as if driving the tip of the balance needle in the lateral direction), so it is possible to accurately detect weak movements of the measured object. can do.

Next, an inclinometer using this angle sensor unit will be described. As shown in FIGS. 13 and 14, this inclinometer includes an angle sensor unit (see FIG. 1) described above, a weight 73 suspended from the yoke 31 via a suspension member 72,
The yoke 31 and the weight 73 are swingably surrounded by an oil-tight casing 74 and the like, and damping oil is enclosed in the casing 74.

When using this inclinometer, the yoke 31 is suspended downward in the vertical plane and the posture of the main body 34 is adjusted so as to divide the rotation range α into approximately two equal parts, and then fixed to the fixing portion.
In this state, the inclination angle of the weight 73 becomes equal to the rotation angle of the yoke 31, so that the inclination angle of the measured object can be accurately measured.

It should be noted that the present invention is not limited to the above-described embodiments, and for example, the present angle sensor unit may be applied to another type of sensor other than the angle sensor and the inclinometer, and other deviations from the gist of the present invention. It goes without saying that various modifications can be made within the range not covered.

[Effect of device]

As described above, the present invention exhibits the following excellent effects.

[I] Since the magnetoresistive element portion is interposed between the magnetic poles of the pair of permanent magnets attached to the yoke, the magnetoresistive element portion has a large magnetic flux density and operates in a stable magnetic circuit. Therefore, it is possible to provide an angle sensor unit having high output sensitivity and good temperature characteristics.

[Ii] A sensor for various purposes can be easily provided by attaching a drive member to the yoke and transmitting the movement of the object to be measured to the yoke via the drive member.

[Iii] As described in [ii], since various sensors share the angle sensor unit, the basic performance and quality of the angle sensor are made uniform, and the types of parts to be stocked for each product. The production system can be rationalized because the number is drastically reduced.

[Iv] A general-purpose angle sensor using this angle sensor unit is provided with an engaging portion on an elastic member fixed to a drive shaft, and further, an acute angle portion is provided at the tip of the drive member attached to the yoke, and the acute angle portion is engaged with the engaging portion. Since it is engaged with the joint, backlash does not occur between the drive member and the elastic member. Therefore, the angular displacement of the drive shaft can be accurately transmitted to the yoke, and the measurement accuracy is improved.

[V] The angle sensor for light torque using this angle sensor unit is configured such that the drive member is attached to the yoke and the tip of the drive member can be driven in a state where the yoke and the drive member are erected in the vertical plane. It is possible to accurately detect a weak movement of the object to be measured.

[Vi] Since the inclinometer using this angle sensor unit detects the inclination angle of the weight as the rotation angle of the yoke, the inclination angle of the measured object can be accurately measured.

[Brief description of drawings]

1 to 6 show an embodiment of the present invention, FIG. 1 is a partially cut side view, and FIGS. 2 and 3 are II in FIG.
-II direction and III-III direction arrow view, FIG. 4 is an enlarged arrow view from IV-IV direction in FIG. 1 (showing the magnetoresistive element portion and terminals, etc.), and FIG. Fig. 6 is a conceptual diagram showing the structure of Fig. 6, Fig. 6 is a characteristic diagram of the angle sensor unit, and Figs. 7 to 10 are examples of general-purpose angle sensors.
FIG. 7 is a partially cutaway side view, and FIGS. 8 and 9 are views as seen from arrows VIII-VIII and IX-IX in FIG.
FIG. 10 is a plan view showing the engagement state of the drive member and the elastic member, and FIGS. 11 and 12 show an angle sensor for light torque.
Figure is a partially cut side view, Figure 12 is XII-XII in Figure 11.
FIG. 13 and FIG. 14 show an example of the inclinometer, FIG. 13 is a partially cut side view, and FIG. 14 is a view from the direction XIV-XIV in FIG. , 15 to 19 show a conventional general-purpose angle sensor,
FIG. 15 is a sectional side view, FIGS. 16 and 17 are arrow views from the XVI-XVI direction and the XVII-XVII direction in FIG. 15, and FIG.
Figure is a view from XVIII-XVIII in Figure 17, Figure 19 is a plan view of the magnetoresistive element part and terminal plate, Figures 20 and 21 show a conventional inclinometer, and Figure 20 is cut. The front view and FIG. 21 are sectional side views. 31 …… Yoke, 32 …… Permanent magnet 33 …… Magnetic resistance element, 34 …… Main body 54 …… Drive shaft, 55 …… Elastic member 56,56a …… Drive member 57 …… Acute corner, 58 …… Off Notch 73 …… Weight, 74 …… Casing

Claims (4)

[Scope of utility model registration request] 1. A non-contact type angle sensor unit for measuring an angle of a yoke which rotates in association with an object to be measured, which is formed by curving a slender plate-like member having magnetic permeability. And a plurality of magnetoresistive elements laminated on a concentric circle composed of a plurality of yokes, each of which has a pair of permanent magnets attached to each other, and which form two symmetrical element portions on both sides of the diameter of the concentric circle. As described above, the magnetoresistive element portion is formed by connecting them in series, and the yoke is supported by the main body so as to rotate within a predetermined angle range via bearings provided at both ends thereof, The magnetoresistive element part is fixed to the main body so as to be concentric with the rotation axis of the yoke and close to the permanent magnet so as to be interposed between the pair of permanent magnets, and the yoke is at the middle angular position. When generated from each permanent magnet A non-contact type angle sensor unit, wherein the pair of permanent magnets are formed at each end of the yoke so that the magnetic flux intersects approximately half of the two element portions and equally. 2. A yoke, which is formed by curving a long and thin plate-like member having magnetic permeability, and which has a pair of permanent magnets mounted inside each of its opposite ends, and a large number of magnetoresistive elements on a concentric circle. And a magnetoresistive element portion in which they are connected in series so as to form two axisymmetric element portions on both sides of the diameter of the concentric circle, and the yoke is provided at both ends thereof. The magnetoresistive element portion is supported by a main body via a bearing provided so as to rotate within a predetermined angle range, and the magnetoresistive element portion is concentric with the rotation axis of the yoke and close to the permanent magnets. It is fixed to the main body so as to be interposed between magnets, and when the yoke is in the middle angular position, the magnetic flux generated from each permanent magnet intersects approximately half and equally of the two element parts. The pair of permanent magnets to the yoke A non-contact type angle sensor formed at each end, which is fixed to a main body so as to surround the drive member and the yoke, and a strip-shaped drive member attached to the outside of the yoke and having an acute angle portion at the tip. A casing, a drive shaft that is rotatably supported by the casing so as to be concentric with the rotation axis of the yoke, and an engaging portion that is fixed to the distal end portion of the drive shaft and that engages with an acute angle portion of the drive member. A general-purpose angle sensor, comprising: a plate-shaped elastic member provided, wherein an acute-angled portion of the drive member is engaged with the engaging portion in a state where the elastic member is elastically deformed. 3. A yoke, which is formed by bending a long and thin plate-like member having magnetic permeability and has a pair of permanent magnets mounted inside each of its opposite ends, and a plurality of magnetoresistive elements on a concentric circle. And a magnetoresistive element portion in which they are connected in series so as to form two axisymmetric element portions on both sides of the diameter of the concentric circle, and the yoke is provided at both ends thereof. The magnetoresistive element portion is supported by a main body via a bearing provided so as to rotate within a predetermined angle range, and the magnetoresistive element portion is concentric with the rotation axis of the yoke and close to the permanent magnets. It is fixed to the main body so as to be interposed between magnets, and when the yoke is in the middle angular position, the magnetic flux generated from each permanent magnet intersects approximately half and equally of the two element parts. The pair of permanent magnets to the yoke A non-contact type angle sensor formed at each end, which has a mounting portion and a rising portion formed by bending a metal strip into an approximately L shape, and a slit is provided at the leading end portion of the rising portion. The driving member is provided on the outside of the yoke through a mounting portion so that the rising portion projects outward of the yoke. The yoke is fixed to the fixed portion so as to stand upright in the vertical plane when in the position, and the slit of the drive member is fitted to the pin of the DUT that is displaced in the horizontal direction. An angle sensor for light torque. 4. A yoke, which is formed by curving a long and thin plate-like member having magnetic permeability and has a pair of permanent magnets attached opposite to each other inside both ends, and a large number of magnetoresistive elements on a concentric circle. And a magnetoresistive element portion in which they are connected in series so as to form two axisymmetric element portions on both sides of the diameter of the concentric circle, and the yoke is provided at both ends thereof. The magnetoresistive element portion is supported by a main body via a bearing provided so as to rotate within a predetermined angle range, and the magnetoresistive element portion is concentric with the rotation axis of the yoke and close to the permanent magnets. It is fixed to the main body so as to be interposed between magnets, and when the yoke is in the middle angular position, the magnetic flux generated from each permanent magnet intersects approximately half and equally of the two element parts. The pair of permanent magnets to the yoke An inclinometer formed at each end, including a weight attached to the outside of the yoke via a suspending member, and a casing that swingably surrounds the yoke and the weight and has damping oil enclosed inside. The main body of the inclinometer is attached to the fixed portion so that the yoke is in the middle angular position when the yoke and the weight are suspended in the vertical plane.