KR101581134B1 - Sensor device - Google Patents

Abstract

(PROBLEM TO BE SOLVED) To provide a sensor device capable of obtaining stable detection accuracy even when the environmental temperature changes.
A magnetic sensor 3 (sensor) mounted on a circuit board 50; a micro-sensor 3 (sensor) mounted on a circuit board 50; And a computer 91 (first electronic component). The temperature of the magnetoresistive element used for the magnetic sensor 3 is set so that the temperature of the magnetoresistive element used for the magnetic sensor 3 becomes constant, Thereby heating the resistance element. Slits 52 and 53 are formed in the circuit board 50 with a part of the circuit board 50 around the magnetic sensor 3 and the slit 53 is formed between the magnetic sensor 3 and the microcomputer 91 And extend in a direction intersecting with a virtual line to be connected.

Description

[0001]

The present invention relates to a sensor device in which a sensor is mounted on a circuit board.

In the sensor device, the sensor is mounted on the circuit board, and the detection result in the sensor is outputted through the circuit board. In a magnetic sensor device having a magnetoresistive element, a magnetoresistive film (magnetosensitive film) made of a magnetoresistive film is formed on one surface of the element substrate, and a two-phase (A-phase and B-phase) The angular velocity, the angular position, and the like of the rotating body are detected based on the output of the bridge circuit of the first embodiment (see, for example, Patent Document 1).

Japanese Laid-Open Patent Publication No. 2012-118000

In many cases, the detection result changes depending on the temperature of the sensor. For example, in a magnetoresistive element used in a magnetic sensor device or a magnetoresistive film used in a Hall element, the resistance value changes depending on the temperature. Therefore, even if a change in the resistance value due to the temperature change occurs due to the constitution of the bridge circuit by the thin film, if the change is equal, no change occurs in the output. However, in a magnetic sensor device using a magnetoresistive film formed on a substrate, even when a bridge circuit is constituted by a magnetoresistive film, a detection error occurs when temperature changes. Although the cause of this phenomenon is not clearly understood, the influence of the stress due to the difference in thermal expansion coefficient between the element substrate and the thin film depends on the position of the element substrate, but the film quality of the thin film depends on the position of the element substrate. .

In view of the above problems, an object of the present invention is to provide a sensor device capable of obtaining stable detection accuracy even when environmental temperature changes.

According to an aspect of the present invention, there is provided a sensor device including a circuit board, a sensor mounted on the circuit board, and a first electronic component mounted on the circuit board, And a heater for heating the sensor element so that the temperature of the sensor element becomes constant based on the detection result at the sensing part, And a slit extending in a direction intersecting a virtual line connecting the sensor and the first electronic component.

In the present invention, a sensor is provided with a warming unit and a heater, and the heater heats the sensor element so that the temperature of the sensor element becomes constant based on the detection result at the warming unit. For this reason, the detection result of the sensor is not well affected by the environmental temperature. The first electronic component is also mounted on the circuit board on which the sensor is mounted, and the circuit board is provided with a slit extending in a direction intersecting a virtual line connecting the sensor and the first electronic component. Therefore, since the heat shield portion (heat shield portion) using the slit is formed between the region where the sensor is mounted on the circuit board and the region where the first electronic component is mounted, The heat conduction between the regions where the first electronic component is mounted is suppressed. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change well, so that the temperature of the sensor element can be precisely controlled by the heater. Therefore, according to the sensor device to which the present invention is applied, stable detection accuracy can be obtained even when the environmental temperature changes.

The present invention is effective when the sensor element has an element substrate and a potentiometer film formed on the element substrate. When the sensor element is a magnetic sensor element having a magnetoresistive film formed on the element substrate, the resistance value of the magnetoresistive film itself changes depending on the temperature, and the stress caused by the difference in thermal expansion coefficient between the element substrate and the magnetoresistive film However, according to the present invention, the influence of such a temperature change can be suppressed.

In the present invention, it is preferable that the slit extends so as to surround the sensor, leaving a part of the circuit board around the sensor. With this configuration, the heat conduction between the region where the sensor is mounted and the region where the first electronic component is mounted is further suppressed. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change very well, so that the temperature of the sensor element can be precisely controlled by the heater.

The circuit board according to the present invention has a holder for holding the circuit board at one end in the axial direction, and the other end of the circuit board is projected toward the one side in the axial direction, And a plurality of circuit board supporting portions for supporting surfaces facing the other side in the axial direction. According to this configuration, the contact area between the holder and the circuit board is narrower than a structure in which the circuit board is supported by the entire one end face in the axial direction of the holder. Therefore, since the heat conduction between the circuit board and the holder can be suppressed, the temperature of the region where the sensor is mounted on the circuit board does not change well. Therefore, the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, the plurality of circuit board support portions may include a first circuit board support portion having an outer dimension smaller than an outer dimension of the circuit board support portion and having a shaft portion projecting from the end face toward the one side in the axial direction, And the circuit board is preferably provided with a first penetrating portion through which the shaft portion is fitted. According to this structure, even when the circuit board is positioned by the shaft portion and the first penetrating portion, heat conduction between the circuit board and the holder can be suppressed. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change well, so that the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, it is preferable that a plurality of the shaft portion and the first penetrating portion are provided, and the position of the circuit board is determined such that the front and back of the circuit board are in a predetermined direction, The plurality of the shaft portions can be fitted to the first penetrating portion, and the predetermined rotational position is only one place within a range of 360 degrees, and at the rotational position excluding the predetermined rotational position, It is preferable that at least one of the shaft portions of the first through-hole can not be fitted with the first through-hole. As described above, in the present invention, the plurality of circuit board support portions and the first penetrating portion are arranged so as not to be rotationally symmetric at a rotation angle except 360 degrees. According to this configuration, when the circuit board is fixed to the holder, the front and back sides thereof are not mistaken. Further, it is possible to fix the circuit board to the holder only when it is positioned at the correct rotational position around the axis. Therefore, it is possible to fix the circuit board with high positional accuracy without fear of fixing the circuit board in a wrong posture. Further, since the management items at the time of production can be reduced, it is possible to produce the material at low cost.

In the present invention, the plurality of circuit board support portions may include a third circuit board support portion that does not protrude from the one end side end face of the shaft portion, and the circuit board includes a first circuit board support portion It is preferable that an abutting portion abutting against the cross section from the other side in the axial direction is formed. According to such a configuration, a point not supported by the first circuit board support portion can be supported by the third circuit board support portion. Therefore, even if the shaft portion is offset from the circumferential direction around the axis to prevent the shaft portion and the first penetration portion from rotationally symmetrical, it is possible to support the load on the circuit board in the circumferential direction around the axis Do. Therefore, deformation of the circuit board at the time of fixation can be suppressed, and a change in the shape of the circuit board due to the release of the residual stress over time can be suppressed. Therefore, deterioration of detection accuracy due to deformation of the circuit board can be suppressed.

In the present invention, it is preferable that the shaft portion fitted to the first penetration portion is adhered to the circuit board with an elastic adhesive. According to such a configuration, when vibration at the time of motor rotation or external vibration is applied, the influence of vibration on the circuit board can be reduced. Therefore, the influence of the vibration on the detection output of the sensor can be reduced, and deterioration of the detection accuracy can be suppressed.

In the present invention, the plurality of circuit board support portions may include a second circuit board support portion having an outer dimension smaller than an outer dimension of the circuit board support portion and having a cylindrical portion projecting toward the one side, Wherein the circuit board is fixed to the holder by a screw which is fixed to the circuit board through the second penetrating portion from the opposite side of the circuit board to the circuit board, Can be adopted. According to such a configuration, it is possible to prevent the screw head from being inserted into the circuit board more than necessary when the screw is fixed. Therefore, breakage of the circuit board and breakage of the thread can be suppressed.

In the present invention, it is preferable that a gap between the shaft portion and the inner circumferential surface of the first penetrating portion is larger than a gap between the tube portion and the inner circumferential surface of the second penetrating portion. With this configuration, the circuit board can be positioned with the second circuit board support portion as a positioning reference.

In the present invention, the plurality of circuit board support portions may include a second circuit board support portion having a fixing hole formed in one end face thereof, and the circuit board is screwed to the fixing hole from the opposite side of the holder A second penetrating portion through which a screw is inserted is formed, and the circuit board is fixed to the holder by the screw. In this configuration, it is preferable that the gap between the shaft portion and the inner circumferential surface of the first penetrating portion is smaller than the gap between the screw and the inner circumferential surface of the second penetrating portion. According to such a configuration, since the opening area of the second through portion can be reduced, the area for accommodating the screw head can be increased. Therefore, it is possible to prevent the screw head from being pushed into the circuit board by the force applied during the screwing. In addition, since the contact area between the second circuit board support portion and the circuit board is wide, the circuit board can be stably supported. In addition, since the circuit board can be positioned with the first circuit board support portion as a positioning reference, the positional accuracy of the circuit board can be prevented from being lowered due to deformation of the screwing point.

In the present invention, it is preferable that the second penetrating portion is a notch formed on an outer edge of the circuit board. According to this configuration, even if the circuit board is fixed by screws, since the fixing position is the outer edge of the circuit board, the fixing position by the screw is separated from the area where the sensor is mounted. Therefore, it is possible to suppress the heat conduction between the region where the sensor is mounted on the circuit board and the holder. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change well, so that the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, it is preferable that a protruding portion for fixing the sensor device protruding to the other side in the axial direction at a plurality of points in the circumferential direction is formed at the other end in the axial direction of the holder. According to this configuration, even when the sensor unit is fixed to the motor case or the like by using the protrusion for fixing the sensor unit, the contact area with the holder and the motor case is small. Therefore, it is possible to suppress the heat conduction between the circuit board and the motor case through the holder. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change well, so that the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, it is preferable that the holder is made of a resin. According to this configuration, since the heat conductivity of the holder is low, it is possible to suppress the heat conduction between the circuit board and the motor case or the like through the holder. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change well, so that the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, it is preferable that the holder has a tubular body portion, and a detection target portion in which a physical quantity is detected by the sensor is disposed inside the tubular body portion. According to this configuration, the air in the tubular body can be stirred by the movement of the detection subject. Therefore, it is possible to suppress the occurrence of the slanting of the temperature distribution, so that the sensor element can be uniformly heated by the heater. Therefore, the temperature of the sensor element can be precisely controlled by the heater.

According to the present invention, in the circuit board, a second electronic component with a heat generation is mounted on the side where the sensor is disposed with respect to the slit, and the second electronic component is mounted on the side of the circuit board on which the sensor is mounted And is preferably mounted on the surface opposite to the surface. According to such a configuration, even when there is a restriction that the second electronic component having a heat generating property must be mounted on the side where the sensor is disposed with respect to the slit, heat transfer between the sensor and the second electronic component can be suppressed. Therefore, since the temperature of the sensor does not change well, the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, in the circuit board, a plurality of through holes are arranged between the sensor and the first electronic component along a direction crossing a virtual line connecting the sensor and the first electronic component desirable. According to such a configuration, thermal conduction can be suppressed by using a through hole, so that the heat conduction between the region where the sensor is mounted and the region where the first electronic component is mounted is suppressed. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change very well, so that the temperature of the sensor element can be precisely controlled by the heater.

In the present invention, the first electronic component is a microcomputer, and the through hole is for writing information on the microcomputer, for example. When such a through hole is used, the lead wire or the like is not connected, so that the through hole can be used to perform the heat shielding.

In the present invention, it is preferable that a plurality of test terminals are disposed between the sensor and the first electronic component in the circuit board along a direction crossing a virtual line connecting the sensor and the first electronic component Do. According to such a configuration, the area where the sensor is mounted and the area where the first electronic component is mounted can be separated. Thus, the heat conduction between the sensor and the first electronic component can be suppressed.

According to the present invention, a sensor is provided with a warming unit and a heater, and the heater heats the sensor element so that the temperature of the sensor element becomes constant based on the detection result at the warming unit. For this reason, the detection result of the sensor is not well affected by the environmental temperature. The first electronic component is also mounted on the circuit board on which the sensor is mounted, and the circuit board is provided with a slit extending in a direction intersecting a virtual line connecting the sensor and the first electronic component. Therefore, since a car heat part using a slit is formed between the area where the sensor is mounted and the area where the first electronic part is mounted on the circuit board, the area where the sensor is mounted and the first electronic part are mounted And the heat conduction between the regions where the heat is generated is suppressed. Therefore, the temperature of the region where the sensor is mounted on the circuit board does not change well, so that the temperature of the sensor element can be precisely controlled by the heater. Therefore, stable detection accuracy can be obtained even when the environmental temperature changes.

1 is an explanatory diagram of a motor equipped with a rotary encoder to which the present invention is applied.
2 is a perspective view of a magnetic sensor device to which the present invention is applied.
3 is an exploded perspective view of a magnetic sensor device to which the present invention is applied.
4 is an explanatory diagram of a rotary encoder provided with a magnetic sensor device to which the present invention is applied;
5 is an explanatory diagram showing a detection principle and the like of an encoder to which the present invention is applied.
6 is an explanatory diagram of a magnetic sensor used in a magnetic sensor device to which the present invention is applied.
Fig. 7 is an explanatory view showing a schematic configuration of a temperature control unit constituted in a control unit of a magnetic sensor device to which the present invention is applied; Fig.
8 is an explanatory diagram of a circuit board used in a magnetic sensor device to which the present invention is applied.
9 is an explanatory diagram of a holder used in a magnetic sensor device to which the present invention is applied.
10 is a plan view of a circuit board used in a magnetic sensor device to which the present invention is applied.
11 is an explanatory diagram of another circuit board used in the magnetic sensor device to which the present invention is applied.
12 is an exploded perspective view of a magnetic sensor device having another type of second circuit board support;
13 is a cross-sectional view of an attachment point of the first circuit board support and the circuit board.

Hereinafter, a magnetic sensor device used for a magnetic rotary encoder in a motor will be described as a sensor device to which the present invention is applied, with reference to the drawings. In the following description, the direction of the axis L of the motor is set to one side L1 on the side opposite to the side on which the output shaft 120 is projected (half output side) and on the side where the output shaft 120 protrudes (Output side) is the other side L2.

(Configuration of motor)

1 (a), 1 (b) and 1 (c) are explanatory diagrams of a motor 100 equipped with a rotary encoder 1 to which the present invention is applied, (Semi-output side) opposite to the output side and a state in which the encoder case 140 is detached from the motor 100 as viewed from the half-output side. 2 is a perspective view of the magnetic sensor device 10 viewed from one side L1 in the axial direction L, and Fig. 3 is an exploded perspective view thereof. 1 (c), components and the like mounted on one side (L1) of the circuit board 50 in the direction of the axis L are omitted. 2 and 3, components and the like mounted on one side (L1) of the circuit board 50 in the direction of the axis L are omitted, except for the connector 94 which will be described later.

The motor 100 shown in Figure 1 has a motor main body 110 and a magnetic rotary encoder 1 formed on the half output side of the motor main body 110. The rotary encoder 1 is connected to the encoder case 140 . In this embodiment, the rotary encoder 1 includes a magnet (not shown) that rotates integrally with the output shaft 120 of the motor 100, and a magnetic sensor device 10 (not shown) facing the magnet on the half- ).

The magnetic sensor device 10 includes a holder 6 fixed to the motor case 130 and a circuit board 50 fixed to the holder 6, And the magnetic sensor 3 is mounted on the other side L2 of the circuit board 50 in the direction of the axis L. In this case, The detailed configuration of the magnetic sensor device 10 and the holder 6 will be described later.

(Configuration of rotary encoder)

4 is an explanatory diagram of a rotary encoder 1 provided with a magnetic sensor device 10 to which the present invention is applied. 5 (a), 5 (b), 5 (c) and 5 (d) illustrate the principle of detection of the rotary encoder 1 to which the present invention is applied, An explanatory diagram showing an electrical connection structure of a B-phase sensitive film, an explanatory diagram of a signal outputted from the magnetic sensor 3, and an explanatory diagram showing the relationship between such signals and the magnitude of the signal of the magnet 20 (output shaft 120) Fig. 7 is an explanatory diagram showing the relationship of the angular position (electrical angle). Fig.

As shown in Fig. 4, the magnet 20 has a magnetized surface 21 magnetized by one pole in the circumferential direction of the N pole and the S pole toward one side L1 of the axis L direction. The magnetic sensor device 10 is provided with a magnetic sensor (magnetic sensor) having a magnetoresistive element 4 (sensor element) opposed to one side L1 of the magnet 20 in the direction of the axis L 3). The magnetic sensor device 10 includes an amplifier section 90 (amplifier section 90 (+ A), an amplifier section 90 (-A), an amplifier section 90 + B), an amplifier section 90 (-B), and an A / D conversion section 97. The magnetic sensor device 10 is also provided with a microcomputer 91 having a signal processing section for detecting the rotational angular position and the rotational speed of the magnet 20 based on the A / D-converted signal from the semiconductor device 92, Respectively. The magnetic sensor device 10 further includes a first Hall element 81 at a position facing the magnet 20 and a second Hall element 81 at a position apart from the machine angle by 90 degrees in the circumferential direction with respect to the first Hall element 81 And the semiconductor device 92 is provided with an amplifier unit 95 for the first Hall element 81 and an amplifier unit 96 for the second Hall element 82. [ Respectively.

The magnetic sensor 3 has a magnetoresistive element 4. The magnetoresistive element 4 includes a device substrate 40 and a two-phase thin film (phase A (SIN) thin film and phase B (COS) having a phase difference of 90 degrees with respect to the phase of the magnet 20, Of the light-shielding film). In this magneto-resistive element 4, the potato film on the A phase is composed of a + A phase (SIN +) thin film 43 and a -A phase (SIN-) which have a phase difference of 180 degrees and detect the movement of the output shaft 120, The B-phase potato film has a + B-phase (COS +) thin film 44 and a -B-phase (COS +) phase shifter having a phase difference of 180 ° and performing movement detection of the output shaft 120, (42).

5A, the one end is connected to the power supply terminal VccA, the other end is connected to the ground (ground), and the other end is connected to the ground And is connected to the terminal GNDA. An output terminal +A for outputting the + A phase is formed at the midpoint position of the active layer 43 on + A, and an output terminal -A for outputting the -A phase is formed at the midpoint position of the active layer 41 on -A have. The + B-phase thin film 44 and the -B-type thin film 42 constitute the bridge circuit shown in FIG. 5 (b) in the same manner as the + A-phase thin film 43 and the -A thin film 41 And one end thereof is connected to the power supply terminal VccB and the other end thereof is connected to the ground terminal GNDB. An output terminal (+ B) for outputting the + B phase is formed at the midpoint position of the + B phase-sensitive film 44, and an output terminal (-B) for outputting the -B phase is formed at the midpoint position of the on- have. 5A and 5B, each of the power supply terminal VccA for the A phase and the power supply terminal VccB for the B phase is described in common. However, the power supply terminal VccA for the A phase and the power supply terminal VccB for the B phase are common . 5, the ground terminal GNDA for the A phase and the ground terminal GNDB for the B phase are described for convenience. However, the ground terminal GNDA for the A phase and the ground terminal GNDB for the B phase are common .

4, the magnetic sensor 3 is disposed on an axis L (rotation center axis) passing through the centers of the magnets 20 and the output shaft 120, and each of the magnetic sensitive films 3, In the in-plane direction of the magnetized surface 21 with the magnetic field strength of the saturation sensitivity region or more of the resistance value of the resistance value of the magnetization direction.

In the magnetic sensor device 10 of this embodiment, a microcomputer 91 for performing signal processing for performing interpolation processing and various arithmetic processing on the sinusoidal signals (sin, cos) output from the magnetic sensor 3 is formed The rotational angle position of the magnet 20 (output shaft 120) is obtained on the basis of the output from the first Hall element 81, the magnetoresistive element 4, the first Hall element 81 and the second Hall element 82. [

More specifically, in the rotary encoder, when the magnet 20 (output shaft 120) makes one rotation, the magnetosensitive element 4 of the magnetic sensor 3 outputs the sinusoidal signal (Fig. 5 sin, cos) are output for two cycles. Therefore, after the sine wave signals sin and cos are amplified by the amplifier section 90 (amplifier sections 90 (+ A), 90 (-A), 90 (+ B), 90 (-B) And outputs such a digital signal to the microcomputer 91, the microcomputer 91 obtains the Lisa ledness shown in Fig. 5 (d). Therefore, the angular position (?) Of the magnet 20 (output shaft 120) can be known by obtaining? = Tan ^-1 (sin / cos) from the sinusoidal signals sin and cos. In the present embodiment, the first Hall element 81 and the second Hall element 82 are arranged at a position deviated by 90 degrees from the rotation center axis (axial line L) of the magnet 20 (output shaft 120) . Therefore, the combination of the outputs of the first Hall element 81 and the second Hall element 82 can determine which section of the sinusoidal wave signal (sin, cos) the current position is located. Therefore, the rotary encoder 1 is capable of detecting the magnet 20 (20) based on the detection result of the magnetoresistive element 4, the detection result of the first hall element 81, and the detection result of the second hall element 82 (Output shaft 120) can be generated, and an absolute operation can be performed.

(Plane configuration of the magnetoresistive element 4)

6 (a), 6 (b) and 6 (c) illustrate a plan view of the magnetic sensor 3 used in the magnetic sensor device 10 to which the present invention is applied, An explanatory diagram showing a sectional configuration, and an explanatory diagram showing a modified example of the sectional configuration. 6 (b) and 6 (c), the layer structure of the magnetoresistive element 4 (the magnetoresistive films 41 to 44), the temperature monitoring resistive film 47, and the heating resistive film 48 is And is represented schematically. 6 (a), right-downward oblique lines are given to the temperature-monitoring resistive film 47 and right oblique lines are given to the resistive film 48 for heating.

6A, in the magnetic sensor 3, the magnetoresistive element 4 includes an element substrate 40, a thin film 41 (not shown) formed on the side 40a of the element substrate 40, 44 and 44 constitute a circular potato region 45 at the center of the element substrate 40 by portions extending back and forth from each other. In the present embodiment, the element substrate 40 is a silicon substrate having a rectangular planar shape.

The power supply terminal VccA for the A phase, the ground terminal GNDA for the A phase, and the output terminal + A (for A phase output) are connected to the end portions of the wiring portions integrally from the power source films 41 to 44, -A phase output terminal (-A), B phase power terminal VccB, B phase ground terminal GNDB, + B phase output terminal (+ B), and -B phase output terminal (-B) are formed.

In the magnetic sensor 3 of this embodiment, a temperature monitoring resistive film 47 (warming portion) and a heating resistive film 48 (heater) are formed on one surface 40a of the element substrate 40 have. Here, the heating resistive film 48 surrounds the entirety of the region in which the resistive films 41 to 44 are formed in a state of extending in the shape of a rectangular frame along the sides of the element substrate 40 to constitute a closed loop . Therefore, the heating resistive film 48 and the insulating films 41 to 44 are formed in regions deviated from the in-plane direction of the element substrate 40, and do not overlap in plan view. The wiring portion 481 is extended from one of the two opposing sides of the heating resistive film 48 and a power supply terminal VccH for the heating resistive film 48 is formed at the end thereof. Respectively. On the other hand, the end portion of the wiring portion 482 extending from the other of the two side portions is connected to the ground terminal GNDA for the A phase. Therefore, the ground terminal GNDA for the A phase is also used as the ground terminal GNDH for the heating resistive film 48. The connecting position of the wiring portion 481 and the heating resistive film 48 and the connecting position of the wiring portion 482 and the heating resistive film 48 are in point symmetrical positions with respect to the potato region 45. [ The resistive film 48 for heating when turned toward the connection position between the wiring portion 482 and the heating resistive film 48 from the connecting position of the wiring portion 481 and the resistive heating film 48 Of the resistive film 48 and the connection position of the wiring portion 482 and the heating resistive film 48 from the connecting position of the wiring portion 481 and the resistive film 48 for heating, (48) are the same.

The temperature monitoring resistive film 47 is formed in the vicinity of the edge of one of the four corners of the heating resistive film 48 in the inner region of the heating resistive film 48, Resistance film 48 as shown in Fig. The temperature-monitoring resistive film 47 has a planar shape elongated while being turned back a plurality of times. Therefore, even if the occupied area is small, the temperature monitoring resistive film 47 can be formed long. Here, the temperature monitoring resistive film 47 is partially overlapped with the wiring portion of the tunable film 44, but is formed in a region deviated from the in-plane direction of the element substrate 40 with respect to the tunable region 45, (45) are not overlapped with each other. At one end of the temperature-monitoring resistive film 47, a power supply terminal VccS for temperature monitoring is formed. The other end of the temperature monitoring resistive film 47 is connected to the ground terminal GNDB for the B phase. Therefore, the ground terminal GNDB for the B phase is also used as the ground terminal GNDS for the temperature monitoring resistive film 47.

(Sectional configuration of the magnetic sensor 3)

The magnetic sensor 3 of the present embodiment has a sectional structure shown in Fig. 6 (b) or a sectional structure shown in Fig. 6 (c). Specifically, as shown in FIG. 6B, a first insulating film 401 made of a silicon oxide film, a second insulating film 402 made of a silicon oxide film, and a second insulating film 403 are formed on one surface 40a of the element substrate 40, And a third insulating film 403 made of polyimide resin or the like are formed. In this embodiment, the thin film resistors 41 to 44 are permalloy films formed by a sputtering method or the like, and the temperature monitoring resistive film 47 and the heating resistive film 48 are all formed of a magnetic film such as a titanium film formed by a sputtering method, And is a conductive film which does not exhibit a resistance effect.

It is to be noted that among the thin film resistors 41 to 44, the temperature monitoring resistive film 47 and the heating resistive film 48, the thin film resistors 41 to 44 are closest to the element substrate 40 (lower side) As shown in Fig. More specifically, the passivation films 41 to 44 are formed between the element substrate 40 and the first insulating film 401. The temperature monitoring resistive film 47 is formed between the first insulating film 401 and the second insulating film 402. The heating resistive film 48 is formed between the element substrate 40 and the first insulating film 401 in the same manner as in the case of the active elements 41 to 44. Therefore, the thin film resistors 41 to 44 are formed on the same layer as the heating resistive film 48, and the resistive film 47 for temperature monitoring is formed on the other layer with the first insulating film 401 therebetween .

6 (c), the active matrix films 41 to 44 are formed between the element substrate 40 and the first insulating film 401. The temperature monitoring resistive film 47 is formed between the first insulating film 401 and the second insulating film 402. The heating resistive film 48 is formed between the first insulating film 401 and the second insulating film 402 in the same manner as the temperature monitoring resistive film 47. Therefore, the thin film resistors 41 to 44 are formed on the other layer with the first insulating film 401 interposed between the temperature monitoring resistive film 47 and the heating resistive film 48, The film 47 and the heating resistive film 48 are formed in the same layer.

(Temperature control of the magnetic sensor 3)

Fig. 7 is an explanatory diagram showing a schematic configuration of a temperature control unit constituted in the semiconductor device 92 of the magnetic sensor device 10 to which the present invention is applied. As shown in Fig. 7, the magnetic sensor device 10 of this embodiment is provided with a temperature control section for controlling the power supply to the heating resistive film 48 based on the resistance change of the temperature monitoring resistive film 47 have. More specifically, the resistor 84 is connected to the temperature monitoring power supply terminal VccS of the temperature monitoring resistive film 47, and the resistance monitoring film 47 is connected to the resistor 84 And the other side is connected to the power supply terminal VccS0. A temperature monitoring ground terminal GNDS is formed on the temperature monitoring resistive film 47 on the side opposite to the side to which the resistor 84 is connected and the temperature monitoring resistive film 47 and the resistor 84 , And is connected in series between the power supply terminal VccS0 and the ground terminal GNDS.

A switching element 83 composed of a bipolar transistor is connected to the heating power supply terminal VccH of the heating resistive film 48. The opposite side of the switching element 83 on which the heating resistive film 48 is connected And is connected to the power supply terminal VccH0. A heating ground terminal GNDH is formed on the heating resistive film 48 on the side opposite to the side to which the switching device 83 is connected and the heating resistive film 48 and the switching element 83 are connected, And is connected in series between the power supply terminal VccH0 and the ground terminal GNDH.

The connecting portion of the temperature monitoring resistive film 47 and the resistor 84 is connected to one terminal of the operational amplifier 85 and the other terminal of the operational amplifier 85 is connected to the switching element 83 And a voltage Vo that is a threshold value for on-off is input. In this state, when the temperature of the element substrate 40 is lowered, the resistance value of the temperature monitoring resistive film 47 is lowered, and the voltage of the connection point divided by the resistor 84 is lowered. The operational amplifier 85 is turned on and the switching element 83 is turned on when the threshold voltage Vo is lower than the threshold value Vo input to the other terminal of the operational amplifier 85 at that time. .

In this state, when the temperature of the element substrate 40 rises, the resistance value of the temperature monitoring resistive film 47 rises and the voltage at the connection point with the resistor 84 rises. The operational amplifier 85 is turned off and the switching element 83 is turned off so that the resistance of the heating resistive film 48 is lower than the threshold value Vo inputted to the other terminal of the operational amplifier 85. [ Is stopped. Therefore, the temperature of the magnetic sensor 3 (the thin film 41 to 44) is maintained at a predetermined temperature defined by the resistance value of the temperature monitoring resistive film 47 and the resistance 84, and the like.

(Detailed configuration of the circuit board 50)

8A and 8B illustrate the circuit board 50 used in the magnetic sensor device 10 according to the present invention and the circuit board 50 on one side in the direction of the axis L (L1), and a bottom view of the circuit board (50) viewed from the other side (L2) in the direction of the axis (L).

8, the circuit board 50 is provided with a magnetic sensor 3, a microcomputer 91 (first electronic component), a semiconductor device 92 (second electronic component), a transistor 93, A connector 94 and the like are mounted. In the present embodiment, the microcomputer 91, the semiconductor device 92, the transistor 93, and the connector 94 are mounted on the side 501 of the circuit board 50 And the magnetic sensor 3 is mounted on the other surface 502 of the circuit board 50 (surface facing the output side of the motor 100).

The circuit board 50 is a printed wiring board on which wirings are formed, such as a phenol substrate or a glass-epoxy substrate. Two slits 52 and 53 are formed in the circuit board 50 around the central region of the circuit board 50 so as to extend leaving portions 50e and 50f of the circuit board 50, The central region of the substrate 50 is an inner mounting region 50a surrounded by the slits 52 and 53. [ In this embodiment, the slits 52 and 53 have two side portions 52a and 53a extending in the X direction and two side portions 52c and 53c extending in the Y direction so as to face each other, And side portions 52b and 53b which extend obliquely, and the inside mounting region 50a is substantially hexagonal.

In this embodiment, the magnetic sensor 3 and the semiconductor device 92 are mounted in the inside mounting area 50a, and the magnetic sensor 3 and the semiconductor device 92 are overlapped in the direction of the axis L. The area of the circuit board 50 sandwiched between the outer edge 50c of the circuit board 50 and the slits 52 and 53 is the outer mounting area 50b. A microcomputer 91 (first electronic component), a transistor 93, a connector 94, and the like are mounted on the outside mounting area 50b. The slit 53 extends in a direction intersecting a virtual line connecting the magnetic sensor 3 and the microcomputer 91. [

More specifically, in the outer mounting area 50b, the connector 94 is mounted along one end in the Y direction of the circuit board 50, and on the opposite side of the inner mounting area 50a to the connector 94 , And the microcomputer 91 and the transistor 93 are disposed at positions separated from each other in the X direction. A plurality of through holes 54 are formed in the region on the side opposite to the inside mounting region 50a with respect to the region sandwiched by the microcomputer 91 and the transistor 93 in the X direction in the outside mounting region 50b, Are arranged in the X direction. The through hole 54 is for writing information on the microcomputer 91. [ The outer mounting region 50b of the circuit board 50 is provided with a plurality of side portions 53b and 53c on the opposite side of the inner mounting region 50a to the side portions 53b and 53c of the slit 53 An inspection terminal 55 is formed.

As shown in Figs. 3 and 8, a plurality of first penetrating portions 56a, 56b, and 56d are formed in the outer mounting region 50b of the circuit board 50. As shown in Fig. The first penetrating portion 56b is formed at a position spaced apart from the first penetrating portion 56a in the X direction and the first penetrating portion 56d is formed at a position spaced apart from the first penetrating portion 56a in the Y direction As shown in Fig. In the present embodiment, the plurality of first penetrating portions 56a, 56b, 56d are formed as holes which are spaced apart from the outer edge 50c of the circuit board 50.

A second penetrating portion 57a is formed between the first penetrating portions 56a and 56d in the outer mounting region 50b of the circuit board 50 and a second penetrating portion 57b is formed between the second penetrating portions 56a and 56d with respect to the inner mounting region 50a. And a second penetrating portion 57b is formed on the side opposite to the second penetrating portion 57a. In the present embodiment, the plurality of second through-holes 57a and 57b are formed as a notch recessed in an arc on the outer edge 50c of the circuit board 50.

The first through holes 56a, 56b and 56d and the second through holes 57a and 57b are used for positioning and fixing the circuit board 50 to the holder 6 described below.

(Configuration of holder 6)

9 (a), 9 (b) and 9 (c) illustrate the holder 6 used in the magnetic sensor device 10 according to the present invention, A bottom view of the holder 6 seen from the other side L2 in the direction of the axis L and a sectional view taken along the line AA 'of the holder 6. Fig. 3 and 9, the holder 6 has a cylindrical body portion 60 having a circular hole concentric with the axial line L, and the holder body 6 has a cylindrical body portion 60, RTI ID = 0.0 > L1. ≪ / RTI > Here, on one end L1 of the tubular body 60 of the holder 6, the circuit board 50 is projected toward one side L1 in the direction of the axis L, A plurality of circuit board support portions 66a, 66b, 66c, and 66d that support the other surface 502 of the circuit board support portion 502 are formed. The circuit board support portions 66a, 66b, 66c, and 66d are formed at approximately equal angular intervals around the axis L.

The one end side L1 of the cylindrical body portion 60 of the holder 6 is also protruded toward one side L1 of the axis L direction between the circuit board support portions 66a and 66d A circuit board support portion 68a for supporting the other surface 502 of the circuit board 50 is formed at the end face of the one side L1 and also between the circuit board support portions 66b and 66c, A circuit board support portion 68b protruding toward the side L1 is formed on the end face of the one side L1 to support the other side 502 of the circuit board 50. [

The circuit board support portions 66a, 66b, and 66d of the circuit board support portions 66a, 66b, 66c, and 66d and the circuit board support portions 68a and 68b are connected to the circuit board support portions 66a 67b and 67d protruding toward one side L1 of the axial line L from the end face 661 are formed on the first circuit board 66a, 66b, 66d, And is a supporting portion. The shaft portions 67a, 67b, 67d are provided on the first penetration portions 56a, 56b, 56d of the circuit board 50 in the circuit board support portions 66a, 66b, 66d (the first circuit board support portion) Is inserted. The circuit board support portions 66a, 66b and 66d are brought into contact with the other surface 502 of the circuit board 50 to support the circuit board 50 at the other side L2 in the direction of the axis L, 67b and 67d position the circuit board 50 in a direction orthogonal to the axis L. [

The circuit board support portion 66c is a third circuit board support portion that does not protrude from the end face 661 toward the axis L direction. Therefore, no penetrating portion is formed at a position overlapping the circuit board supporting portion 66c (third circuit board supporting portion) in the circuit board 50. [ The one side L1 of the circuit board support portion 66c in the direction of the axis L is connected to the circuit board support portion 66c in the other surface 502 of the circuit board 50, And only the circuit board 50 is supported on the other side L2 in the direction of the axis L by abutting against the circuit board 503.

The circuit board support portions 68a and 68b are provided with cylindrical portions 69a and 69b which have external dimensions smaller than the external dimensions of the circuit board support portions 68a and 68b and protrude toward one side L1 of the axis L direction And the cylindrical portions 69a and 69b are located inside the second through-holes 57a and 57b (notch) of the circuit board 50. The second circuit board support portion includes a second circuit board support portion.

As shown in Fig. 3, the cylindrical portions 69a and 69b are formed with second through-holes 57a (57a and 69b) on the side opposite to the holder 6 (one side L1 in the axial direction L) The screw heads 58a and 59a of the screws 58 and 59 press the circuit board 50 firmly against the circuit board support portions 68a and 68b . The shaft portions 58b and 59b of the screws 58 and 59 are sandwiched by the second through portions 57a and 57b (notch) to position the circuit board 50 on both sides in the X direction, And the substrate 50 is positioned in the Y direction.

The first penetration portions 56a, 56b, and 56d of the circuit board support portions 66a, 66b, and 66d formed in the holder 6 and the circuit board 50 formed at the positions overlapping the circuit board support portions 66a, Thereby constituting three sets of engaging portions. These fitting portions are arranged at three places among four corners of the circuit board 50 (four places set at an approximately constant angular spacing around the axis L). The other one of the four corners of the circuit board 50 is not provided with a through portion because there is no shaft portion on the circuit board support portion 66c and the other end portion of the circuit board support portion 66c is in contact with the end face 661 of the circuit board support portion 66c, (503). The circuit board support portions 68a and 68b formed on the holder 6 and the second penetration portions 57a and 57b (notch) of the circuit board 50 formed at the positions overlapping the circuit board support portions constitute two sets of fitting portions , And these are arranged at the end edges of both sides of the circuit board 50 in the X direction. The above-described five fitting portions align the circuit board 50 with respect to the holder 6 in the direction orthogonal to the axial line L.

10 is a plan view of the circuit board 50 used in the magnetic sensor device 10 to which the present invention is applied and shows a state viewed from one side L1 of the axis L direction. The gap between the shaft portions 67a, 67b and 67d of the circuit board support portions 66a, 66b and 66d formed in the holder 6 and the inner circumferential surfaces of the first penetration portions 56a, 56b and 56d formed in the circuit board 50 Are all dimension D1. The clearances between the cylindrical portions 69a and 69b of the circuit board support portions 68a and 68b and the inner peripheral surfaces of the second through holes 57a and 57b are both dimension D2. In this embodiment, the dimensions of both gaps are set so that D1 > D2. Therefore, the positioning of the circuit board 50 is performed with the circuit board supporting portions 68a and 68b (second circuit board supporting portion) as a positioning reference.

In the holder 6, the sensor unit fixing projecting portions 63a and 63b protruding from the plurality of points in the circumferential direction to the other side L2 in the axial direction L are formed at the other end L2 of the axis L direction, 63b and 63c are formed in the cylindrical body 60. The protrusions 63a, 63b and 63c also protrude outward in the radial direction from the cylindrical body 60. Holes 64a, 64b and 64c are formed in the projecting portions of the projecting portions 63a, 63b and 63c outwardly in the radial direction from the cylindrical body portion 60. [

The protrusions 63a, 63b and 63c and the protrusions 63a and 63b and 63c and the protrusions 63a and 63b and 63c are used for fixing the sensor 6 to the motor case 130 shown in Fig. . More specifically, in the projecting portions 63a, 63b and 63c, the other end L2 in the direction of the axis L is in contact with the motor case 130. In this state, the motor case 130 is provided with holes 64a (See Fig. 1 (c) and Fig. 2) are stopped through the screws 64, 64b, 64c. A concave portion 62 is formed on the other side (L2) of the holder 6 in the direction of the axis L to suppress the sink marks when the holder 6 is resin molded.

(Main effect of this embodiment)

As described above, the magnetic sensor device 10 (sensor device) of the present embodiment includes the circuit board 50, the magnetic sensor 3 (sensor) mounted on the circuit board 50, and the circuit board 50 And a microcomputer 91 (a first electronic component) The resistive film 47 for temperature monitoring and the resistive film 48 for heating are formed on the magnetic sensor 3 and the resistive film 48 for heating is formed on the surface of the resistance- The magnetoresistive element 4 is heated so that the temperature of the magnetoresistive element 4 becomes constant based on the detection result of the magnetostrictive element 47. [ Therefore, the detection result of the magnetic sensor 3 is not well affected by the environmental temperature.

Here, the circuit board 50 is formed with a slit 53 extending in a direction intersecting a virtual line connecting the magnetic sensor 3 and the microcomputer 91. Therefore, on the circuit board 50, a car heat part using the slit 53 is formed between the area where the magnetic sensor 3 is mounted and the area where the microcomputer 91 is mounted. Therefore, the heat conduction between the area where the magnetic sensor 3 is mounted and the area where the microcomputer 91 is mounted is suppressed. The circuit board 50 is extended around the magnetic sensor 3 so as to surround the magnetic sensor 3 with a part of the circuit board 50 left. This further suppresses the thermal conduction between the inside mounting area 50a on which the magnetic sensor 3 is mounted and the outside mounting area 50b on which the microcomputer 91 is mounted. Therefore, since the temperature of the inside mounting area 50a on which the magnetic sensor 3 is mounted on the circuit board 50 is not well affected by the outside mounting area 50b, the temperature of the magnetoresistive element 4 is heated The resistive film 48 can be precisely controlled. Therefore, according to the magnetic sensor device 10 of the present embodiment, stable detection accuracy can be obtained even when the environmental temperature changes. In the magnetic sensor 3, even when the magnetoresistive element 4 is heated by the heating resistive film 48, such heat is hardly transmitted to the microcomputer 91. Therefore, the reliability of the microcomputer 91 such as malfunction can be prevented from deteriorating.

Particularly in this embodiment, the sensor device is a magnetic sensor device 10 having a magnetoresistive element 4 as a sensor element. In the magnetoresistive element 4, the resistance value of the magnetoresistive films 41 to 44 itself changes with temperature, and the stress caused by the difference in thermal expansion coefficient between the element substrate 40 and the magnetoresistive films 41 to 44 Is influenced by the temperature due to the difference in the position of the element substrate 40 and the like. However, according to this embodiment, the influence of the temperature change can be suppressed.

The portion of the holder 6 that supports the circuit board 50 includes a plurality of circuit board support portions 66a, 66b, 66c, 66d, 68a, 68b. The circuit board 50 is positioned by the shaft portions 67a, 67b, 67d of the circuit board support portions 66a, 66b, 66d. Therefore, since the contact area between the holder 6 and the circuit board 50 is narrow, the heat conduction between the holder 6 and the circuit board 50 can be suppressed. Since the second penetration portions 57a and 57b where the screws 58 and 59 are stopped on the circuit board 50 are notches formed in the outer edge 50c of the circuit board 50, And the fixing position by the screws 58 and 59 is spaced apart from the inner mounting area 50a. This makes it possible to suppress the heat conduction between the inner mounting area 50a on which the magnetic sensor 3 is mounted and the holder 6 on the circuit board 50. [ Therefore, since the temperature of the inner mounting area 50a on which the magnetic sensor 3 is mounted on the circuit board 50 does not change well, the temperature of the magnetoresistive element 4 is changed by the heating resistive film 48 Precise control is possible. Therefore, according to the magnetic sensor device 10 of the present embodiment, stable detection accuracy can be obtained even when the environmental temperature changes.

Here, the magnetic sensor device 10 is provided with the circuit board 50 on which the magnetoresistive elements 4 having terminals 41 to 44 and terminals are mounted on the element substrate 40, 50 are fixed to the holder 6, the shape of the circuit board 50 changes as time elapses so as to release the residual stress. When the shape of the circuit board 50 changes, There is a problem that the detection output changes with time.

For such a problem, it is desirable to improve the accuracy of the fixing surface on which the circuit board 50 is fixed and the accuracy of the fixing position of the circuit board 50. For example, in this embodiment, since the contact area between the holder 6 and the circuit board 50 is narrow (small), the accuracy of the fixing surface for supporting the circuit board 50 is small. Therefore, it is possible to manufacture the holder at a low cost, which facilitates the accuracy control of the fixing surface and the precision of the fixing surface.

The circuit board support portions 66a, 66b, 66c, and 66d are disposed at substantially equal angular intervals around the axis L to evenly support the circuit board 50 at four places. The circuit board support portions 68a and 68b serving as screw tightening points are also arranged symmetrically on both sides of the circuit board 50. [ By this equal arrangement, deformation of the circuit board 50 at the time of fixation can be suppressed, and a change in the shape of the circuit board 50 due to the release of residual stress due to deformation at the time of fixation over time is suppressed . Therefore, deterioration of detection accuracy due to deformation of the circuit board 50 can be suppressed. It is preferable that the circuit board support portions 66a, 66b, 66c, and 66d are disposed at substantially equal angular intervals around the axial line L. However, It may be dispersed. Even in this arrangement, since the load of the circuit board 50 can be dispersed and supported in the circumferential direction around the axis L, the shape change of the circuit board 50 can be suppressed.

The circuit board 50 has a plurality of shaft portions (shaft portions 67a, 67b and 67d) and a plurality of first penetration portions (first penetration portions 56a, 56b and 56d) with respect to the holder 6 And is positioned in a direction orthogonal to the axial line L by being fitted in three places. These three sets of fitting portions are formed in three of the four corners of the circuit board 50, and the remaining one of the four corners is not formed with a penetrating portion, but is a simple abutment portion 503. Therefore, only when the front and back surfaces of the circuit board 50 are in the correct direction and the rotational position around the axis L of the circuit board 50 is a predetermined correct rotational position, all three of the shaft portions are connected to the first through- It is possible to engage it. In addition, the rotational positions at which all the three shaft portions are fitted to the first penetrating portion are only one in the range of 360 degrees. Therefore, when the circuit board 50 is fixed with respect to the holder 6, the front and rear positions and the rotational position of the circuit board 50 are not wrong. Therefore, it is possible to fix the circuit board 50 at a high positional accuracy without fear of fixing the circuit board 50 in a wrong posture. Further, since the management items at the time of production can be reduced, it is possible to produce the material at low cost.

Cylinders 69a and 69b are formed on the circuit board support portions 68a and 68b (second circuit board support portion) of the holder 6 and the circuit board 50 is positioned on the basis of the positioning reference, Screw tightened. The screws 58 and 59 are stopped at the position where the screw heads 58a and 59a abut against the cylinder portions 69a and 69b and the screw heads 58a and 59b are stopped further than the screw heads 58a and 59b, 59a do not dig into the circuit board 50. Therefore, it is possible to prevent the circuit board 50 from being broken or the screw thread to be broken when the screw is temporarily tightened without tight torque control when tightening the screw.

The contact area between the holder 6 and the motor case 130 is narrow because the holder 6 is fixed to the motor case 130 by the projecting portions 63a, 63b and 63c for securing the sensor device. The holder 6 is made of resin. Therefore, heat conduction between the circuit board 50 and the motor case 130 through the holder 6 can be suppressed. Therefore, since the temperature of the inner mounting area 50a on which the magnetic sensor 3 is mounted on the circuit board 50 does not change well, the temperature of the magnetoresistive element 4 is changed by the heating resistive film 48 Precise control is possible. Therefore, according to the magnetic sensor device 10 of the present embodiment, stable detection accuracy can be obtained even when the environmental temperature changes.

The magnet 20 (detection subject) whose magnetic flux density (physical quantity) is detected by the magnetic sensor device 10 is rotated with the rotation of the output shaft 120, The air in the tubular body 60 can be agitated. Therefore, it is possible to suppress the occurrence of the slanting of the temperature distribution, so that the heat of the resistive film for heating 48 can be widely spread to the magnetoresistive element 4. Therefore, since the temperature of the inner mounting area 50a on which the magnetic sensor 3 is mounted on the circuit board 50 does not change well, the temperature of the magnetoresistive element 4 is changed by the heating resistive film 48 Precise control is possible. Therefore, according to the magnetic sensor device 10 of the present embodiment, stable detection accuracy can be obtained even when the environmental temperature changes.

In the circuit board 50, the semiconductor device 92 (second electronic component) is mounted on the inside mounting area 50a, and the semiconductor device 92 has heat generation. However, the semiconductor device 92 is mounted on the circuit board 50 on the side opposite to the side where the magnetic sensor 3 is mounted. Therefore, heat transfer between the semiconductor device 92 and the magnetic sensor 3 can be suppressed. Therefore, the temperature of the magnetoresistive element 4 can be precisely controlled by the heating resistive film 48 since the temperature of the magnetic sensor 3 does not change well. Therefore, according to the magnetic sensor device 10 of the present embodiment, stable detection accuracy can be obtained even when the environmental temperature changes.

(Evaluation result on the heat effect)

First, in a state where the magnetic sensor device 10 was turned off, hot air was blown from the hot air toward the side surface of the motor 100, and the temperature after the heating was stopped was measured at each site. The results are shown in Table 1. The environmental temperature is 30 占 폚.

0 minutes After 10 minutes 20 minutes later The temperature of the side surface of the motor case 130 51.7 DEG C 48.8 DEG C 47.0 DEG C The temperature of the side surface of the holder 6 37.7 DEG C 40.5 DEG C 39.0 DEG C The temperature of the semiconductor device 92 35.6 ° C 37.5 DEG C 36.4 DEG C

As shown in Table 1, the temperature of the motor case 130 was 51.7 占 폚 while the temperature of the holder 6 was 37.7 占 폚 and the temperature of the semiconductor device 92 was 35.6 占 폚. Therefore, it can be seen that the thermal conductivity from the motor case 130 to the magnetic sensor device 10 is low. The same results were obtained after 10 minutes and 20 minutes from the end of heating.

Next, the semiconductor device 92, the transistor 93, and the microcomputer (not shown) in a state in which the resistance film 48 for heating the magnetic sensor device 10 is energized to set the temperature of the magnetic sensor 3 to 70 deg. 91) were measured. The results are shown in Table 2. The environmental temperature is 30 占 폚.

The temperature of the magnetic sensor 3 70 ℃ The temperature of the semiconductor device 92 68.1 DEG C The temperature of the transistor 93 50.0 DEG C The temperature of the microcomputer 91 51.6 ° C

As can be seen from Table 2, the temperature of the semiconductor device 92 was 68.1 캜, which was 1.9 캜 lower than the temperature of the magnetic sensor 3. The temperature of the transistor 93 mounted on the outside mounting area 50b was 50.0 캜 and was 20.0 캜 lower than the temperature of the magnetic sensor 3. The temperature of the microcomputer 91 mounted on the outside mounting area 50b was 51.6 deg. C, which was 18.4 deg. C lower than the temperature of the magnetic sensor 3.

(Another embodiment of the circuit board 50)

11 is an explanatory diagram of another circuit board 150 used in the magnetic sensor device 10 to which the present invention is applied. Since the basic configuration of this embodiment is the same as that described with reference to Fig. 7, the same reference numerals are given to common portions, and a description thereof will be omitted.

11, in this embodiment, between the magnetic sensor 3 and the microcomputer 91 (first electronic component) in the outer mounting area 50b of the circuit board 150, a magnetic sensor 3 And a plurality of through holes 54 are arranged along the X direction crossing a virtual line connecting the microcomputer 91 (first electronic component). The through hole 54 is used for writing information to the microcomputer 91, and no lead wire or the like is connected.

With this configuration, the thermal conduction between the region where the magnetic sensor 3 is mounted and the region where the microcomputer 91 is mounted can be suppressed by the through hole 54. [

A magnetic sensor 3 and a microcomputer 91 (not shown) are provided between the magnetic sensor 3 and the microcomputer 91 (first electronic component) in the outer mounting area 50b of the circuit board 150 A plurality of inspection terminals 55 are arranged along the X direction crossing the imaginary line connecting the two electronic components (one electronic component). Such inspection terminals 55 are not connected to leads or the like for inspection in the magnetic sensor device 10 alone. The other configuration is substantially the same as that of the circuit board 50 described with reference to Fig. With this configuration, since the area where the magnetic sensor 3 is mounted and the area where the microcomputer 91 is mounted can be separated, the area where the magnetic sensor 3 is mounted and the area where the microcomputer 91 is mounted The thermal conduction between the mounted regions can be suppressed by the through holes 54. [

(Another embodiment in which the fixing structure of the circuit board 50 is different)

(1) In each of the above-described configurations, the shaft portions 67a, 67b, 67d of the circuit board supporting portions 66a, 66b, 66d (first circuit board supporting portion) and the inner peripheries of the first penetrating portions 56a, 56b, 56d The dimension D1 of the gap and the dimension D2 of the gap between the cylindrical portions 69a and 69b of the circuit board supporting portions 68a and 68b (second circuit board supporting portion) and the inner peripheral surfaces of the second through holes 57a and 57b The dimensions of both gaps may be set such that the relationship D1 < D2, which is the opposite of the above-mentioned form. In this case, the circuit board 50 is positioned with the circuit board supporting portions 66a, 66b, 66d (first circuit board supporting portion) as a positioning reference. Therefore, it is possible to suppress the positional accuracy of the circuit board 50 from being lowered due to deformation of the screw fastening point of the screw fastening.

(2) FIG. 12 is an exploded perspective view of a magnetic sensor device having another type of second circuit board support portion. The holder 206 is provided with circuit board support portions 268a and 268b (second circuit board support portions) of a shape that is formed by removing the cylindrical portions 69a and 69b of the circuit board support portions 68a and 68b of the above- Respectively. Fixing holes 269a and 269b are opened at the distal end face 270 (one end side (L1) end face in the direction of the axis L) of the circuit board support portions 268a and 268b. On the other hand, on the circuit board 250, second through holes 257a and 257b (notches) are formed at positions overlapping with the fixing holes 269a and 269b.

The second through-holes 257a and 257b have a smaller notch width than the second through-holes 57a and 57b of the above-described shape. The second penetrating portions 257a and 257b may be notch wide enough to allow the shaft portions 58b and 59b of the screws 58 and 59 to be inserted therethrough when the cylindrical portions 69a and 69b are not formed. With such a configuration, the area occupied by the screw heads 58a and 59a can be increased as the notch widths of the second through-holes 257a and 257b are narrowed. Therefore, it is possible to prevent the screw heads 58a, 59a from being pushed into the circuit board 250 by the force applied during the screwing. In addition, since the front end surface 270 of the circuit board support portions 268a, 268b abuts against the circuit board 250, the circuit board 250 can be stably supported.

12, when the dimension of the clearance between the inner peripheral surface of the second through-holes 257a, 257b and the shaft portions 58b, 59b of the screws 58, 59 is D3 (not shown), D3> D1. That is, the positioning of the circuit board 250 is performed with the circuit board supporting portions 66a, 66b, and 66d (first circuit board supporting portion) as a positioning reference. Therefore, it is possible to suppress the positional accuracy of the circuit board 250 from being lowered due to deformation of the screw fastening point or the like.

(3) In each of the above embodiments, the shaft portions 67a, 67b, 67d of the circuit board supporting portions 66a, 66b, 66d (first circuit board supporting portion) may be bonded to the circuit board 50 with an elastic adhesive. The bonding point may be at least one of the three points. 13 is a cross-sectional view of an adhesion point between the first circuit board support and the circuit board 50. Fig. In Fig. 13, the position of the shaft portion 67a is shown, but the other shaft portions 67b and 67d can be bonded in the same manner. The elastic adhesive 300 flows from the top of the circuit board 50 around the tip end of the shaft portion 67a inserted in the first penetrating portion 56a and bonded. As the elastic adhesive 300, for example, a resin such as a potting material is used. In Fig. 13, the elastic adhesive 300 does not flow into the gap between the inner peripheral surface of the first penetrating portion 56a and the outer peripheral surface of the shaft portion 67a, but may flow.

By bonding in this way, the circuit board 50 is supported by the elastic body (elastic adhesive 300). 67b / 67d, the end portion of the circuit board 50 other than the screwing point may cause resonance if vibration or external vibration is applied to the magnetic sensor device 10. However, The circuit board 50 can be fixed to other than the screws. Therefore, the influence of the vibration on the circuit board 50 can be reduced, and the influence on the detection output of the sensor can be reduced. Therefore, it is possible to suppress deterioration in detection accuracy due to vibration.

(Evaluation result on fixed structure)

In the case of a beta attachment structure (conventional structure) in which the circuit board 50 is mounted on and fixed to a plane, a change over time of the sensor detection output value due to the fact that the circuit board is deformed when fixed and the residual stress is released over time is 20 mV or more. On the other hand, in the embodiment of the present invention shown in Fig. 3 and others, it has been confirmed that the change over time of the sensor detection output value is about 0.5 mV.

(Other forms)

In the above embodiments, the magnetic sensor device 10 is exemplified as the sensor device, but the present invention may be applied to other sensor devices such as an optical sensor device.

1: rotary encoder
3: magnetic sensor
4: Magnetoresistance element (sensor element)
6: Holder
10: Magnetic sensor device
20: Magnet
21:
40: element substrate
40a: one side
41 to 44:
45: Potato area
47: Resistance film for temperature monitoring (warming part)
48: Resistance film for heating (heater)
50: circuit board
50a: inner mounting area
50b: outer mounting area
50c: outer edge of the circuit board
52, 53: slit
54: Through hole
55: inspection terminal
56a, 56b, and 56d:
57a, 57b: second penetrating portion (notch)
58, 59: Screw
58a, 59a: screw head
58b, 59b:
60: Tongue
62:
63a, 63b, 63c:
64a, 64b, 64c: holes
66a, 66b, 66d: circuit board support portion (first circuit board support portion)
66c: circuit board supporting portion (third circuit board supporting portion)
67a, 67b, 67d:
68a, 68b: circuit board support portion (second circuit board support portion)
69a, 69b:
81, 82: Hall element
83: Switching element
84: Resistance
85: Op Amp
90:
91: Microcomputer (first electronic component)
92: Semiconductor device (second electronic part)
93: transistor
94: Connector
95, 96: amplifier section
97:
100: motor
110: motor body
120: Output shaft
130: Motor case
140: Encoder case
150: circuit board
190: Screw
206: Holder
250: circuit board
257a, 257b:
268a, 268b: circuit board support portion (second circuit board support portion)
269a, 269b: Fixing hole
270:
300: Elastic adhesive
401, 402, 403: insulating film
481, 482: wiring part
501: one side
502:
503:
661: section
L: Axis
L1: One side
L2: the other side

Claims (22)

A circuit board,
A sensor mounted on the circuit board,
And a first electronic component mounted on the circuit board,
Wherein the sensor has a sensor element, a sensor section for detecting the temperature of the sensor element, and a heater for heating the sensor element so that the temperature of the sensor element is constant based on the detection result at the sensor section,
Wherein the circuit board is provided with a slit extending in a direction intersecting with a virtual line connecting the sensor and the first electronic component. The method according to claim 1,
Wherein the sensor element has an element substrate and a potantium film formed on the element substrate. 3. The method of claim 2,
Wherein the slit extends so as to surround the sensor, leaving a part of the circuit board around the sensor. The method of claim 3,
And a holder for holding the circuit board at an end on one side in the axial direction,
The end of the one side has a plurality of circuit board support portions projecting toward the one side in the axial direction and supporting a surface of the circuit board facing the other side in the axial direction on an end surface of the one side Characterized in that 5. The method of claim 4,
Wherein the plurality of circuit board support portions include a first circuit board support portion having outer dimensions smaller than the outer dimensions of the circuit board support portion and having a shaft portion projecting from the end face toward the one side in the axial direction,
Wherein the circuit board has a first penetrating portion in which the shaft portion is fitted. 6. The method of claim 5,
A plurality of the shaft portions and the first penetrating portions,
When the front and back sides of the circuit board are positioned in a predetermined direction with respect to the holder and the circuit board is positioned so as to be at a predetermined rotational position around the axis, all of the plurality of the shaft portions are engaged with the first through- As a result,
Wherein the predetermined rotation position is only one place within a range of 360 degrees and at least one of the plurality of the shaft portions can not be fitted with the first penetration portion at a rotation position other than the predetermined rotation position Device. The method according to claim 6,
The plurality of circuit board support portions include a third circuit board support portion in which the shaft portion is not protruded from the one end side end face,
Wherein the circuit board is provided with an abutment portion abutting against the one end surface of the third circuit board support portion from the other side in the axial direction. 8. The method of claim 7,
And the shaft portion fitted to the first penetrating portion is bonded to the circuit board by an elastic adhesive. 9. The method according to any one of claims 4 to 8,
Wherein the plurality of circuit board support portions include a second circuit board support portion having an outer size smaller than an outer dimension of the circuit board support portion and having a barrel protruding toward the one side,
Wherein the circuit board has a second penetrating portion through which the barrel is fitted,
Wherein the circuit board is fixed to the holder by a screw which is stopped from the cylinder through the second penetrating portion from the side opposite to the holder with respect to the circuit board. 9. The method according to any one of claims 5 to 8,
Wherein the plurality of circuit board support portions include a second circuit board support portion having an outer size smaller than an outer dimension of the circuit board support portion and having a barrel protruding toward the one side,
Wherein the circuit board has a second penetrating portion through which the barrel is fitted,
Wherein the circuit board is fixed to the holder by a screw which is stopped from the tube through the second penetrating portion from the side opposite to the holder with respect to the circuit board,
And the gap between the shaft portion and the inner circumferential surface of the first penetrating portion is larger than the gap between the tube portion and the inner circumferential surface of the second penetrating portion. 11. The method of claim 10,
And the second penetrating portion is a notch formed on an outer edge of the circuit board. 9. The method according to any one of claims 4 to 8,
Wherein the plurality of circuit board support portions include a second circuit board support portion having a fixing hole formed in one end face thereof,
A second penetrating portion through which a screw screwed into the fixing hole is inserted is formed in the circuit board from the side opposite to the holder,
Wherein the circuit board is fixed to the holder by the screw. 9. The method according to any one of claims 5 to 8,
Wherein the plurality of circuit board support portions include a second circuit board support portion having a fixing hole formed in one end face thereof,
A second penetrating portion through which a screw screwed into the fixing hole is inserted is formed in the circuit board from the side opposite to the holder,
Wherein the circuit board is fixed to the holder by the screw,
And the gap between the shaft portion and the inner circumferential surface of the first penetrating portion is smaller than the gap between the screw and the inner circumferential surface of the second penetrating portion. 14. The method of claim 13,
And the second penetrating portion is a notch formed on an outer edge of the circuit board. 5. The method of claim 4,
And a protruding portion for fixing the sensor device protruding from a plurality of points in the circumferential direction to the other in the axial direction is formed at the other end of the holder in the axial direction. 16. The method of claim 15,
Wherein the holder is made of resin. 17. The method of claim 16,
The holder includes a tubular body portion,
And a detection target portion in which a physical quantity is detected by the sensor is disposed inside the tubular body portion. The method according to claim 1,
In the circuit board, a second electronic component with a heat generating property is mounted on the side where the sensor is arranged with respect to the slit,
Wherein the second electronic component is mounted on a surface of the circuit board opposite to the side on which the sensor is mounted. The method according to claim 1,
Wherein a plurality of through holes are arranged between the sensor and the first electronic component in the circuit board along a direction crossing a virtual line connecting the sensor and the first electronic component. . 20. The method of claim 19,
The first electronic component is a microcomputer,
Wherein the through hole is for writing information on the microcomputer. The method according to claim 1,
Wherein a plurality of test terminals are disposed between the sensor and the first electronic component along a direction crossing a virtual line connecting the sensor and the first electronic component in the circuit board. . The method according to claim 1,
The circuit board includes two slits extending around a central region of the circuit board while leaving a part of the circuit board. The center region of the circuit board has the sensor disposed in an area surrounded by two slits And the sensor device.

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