JPH11237395A - Rotary sensor and magnetic detection ic for rotary sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the productivity of a rotary sensor by improving the yield of a Hall element, at the same time by easily arranging the Hall element corresponding to the size, the shape, or the like of a rotator. SOLUTION: A rotary sensor is provided with first and second Hall elements H1 and H2 being arranged near a mission gear and an amplification part 200 for amplifying the difference of output voltages from the first and second Hall elements H1 and H2 on a magnetic detection IC 12. The rotary sensor detects the speed of the mission gear with a plurality of cogs in a circumferential direction. In this case, the first Hall element H1, the second Hall element H2, and the amplification part 200 are separately arranged on a GND substrate 100 consisting of a lead frame, and the first and second Hall elements H1 and H2 and the amplification part 200 are electrically wired for connecting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rotation sensor for detecting at least the number of rotations of a rotating body having a plurality of teeth in a circumferential direction, and a magnetic detection IC for the rotation sensor.
The present invention relates to a rotation sensor and a magnetic sensor IC for a rotation sensor using a Hall element that detects a magnetic flux that changes with the rotation of a rotator to detect a rotation speed, a rotation angle, and the like of the rotator.

[0002]

2. Description of the Related Art It is known to detect the number of revolutions of a rotator based on a difference between output voltages of two Hall elements provided along a rotator such as a gear (for example, Japanese Patent Laid-Open No. 6-273).
No. 437).

[0003] The specific configuration example is as follows: (1) A structure in which two Hall elements and an amplifying section for amplifying a detection signal from each Hall element are formed on the same semiconductor substrate. (2) A device in which two Hall elements are formed on one semiconductor substrate and a voltage difference between these Hall elements is detected (see, for example, JP-A-6-164015). (3) Two Hall elements are formed on one semiconductor substrate, and an amplifying unit for amplifying a detection signal from the two Hall elements is provided on, for example, a circuit board provided separately from the semiconductor substrate. (See, for example, Japanese Patent Publication No. 64-52789). Etc. are known.

[0004]

In this type of rotation sensor, it is necessary to change the distance between the two Hall elements according to the size and shape of the rotating body to be detected. Specifically, the distance between the two Hall elements is determined by the distance between the teeth of the rotating body. In the differential detection type, the distance is generally set to approximately の of the distance between the teeth.

However, in the conventional rotation sensor, two Hall elements are formed on one semiconductor substrate. Therefore, when changing the interval between the two Hall elements, it is necessary to change the mask pattern. .

That is, a number of mask patterns are prepared in accordance with the size and shape of the rotating body, and different mask patterns are used for different types (sizes and the like) of the rotation sensor determined by the size and shape of the rotating body. One Hall element must be formed, and there is a problem that the versatility of the mask is low.

Further, since the interval between the teeth of the rotating body is very large as compared with the chip size of a general semiconductor, when two Hall elements are formed on the same semiconductor substrate, 1 is required.
One chip must be very large,
The number of chips manufactured from one wafer is reduced.

In particular, in the configuration of (3), since an amplification section is provided outside a chip having a large size (a semiconductor chip on which two Hall elements are formed), it is inevitable that two amplifiers are provided. There is a possibility that the wiring length between the Hall element and the amplifying unit becomes long, and the wiring becomes weak to noise.

The present invention has been made in view of such a problem, and can improve the yield of Hall elements, and furthermore, the arrangement of the Hall elements in accordance with the size and shape of the rotating body is, for example, described later. An object of the present invention is to provide a rotation sensor and a magnetic detection IC for the rotation sensor, which can be easily performed in a die bonding step in the process and can improve the productivity of the rotation sensor.

Another object of the present invention is to provide a rotation sensor and a magnetic detection IC for a rotation sensor which can suppress noise contamination and improve detection accuracy in addition to the above conditions. It is in.

[0011]

According to the present invention, there is provided a rotation sensor for detecting at least the number of rotations of a rotating body having a plurality of teeth in a circumferential direction, wherein two Hall elements arranged close to the rotating body are provided. And an amplifying unit for amplifying a difference between output voltages from the two Hall elements, wherein the two Hall elements and the amplifying unit are individually arranged on a substrate formed of a lead frame, and The two Hall elements and the amplifying unit are electrically connected to each other by wiring.

That is, the two Hall elements and the amplifying unit are separately formed, and are individually arranged on the substrate.

In this case, as a method of arranging the two Hall elements, for example, a method of arranging them at predetermined intervals in a direction along the rotation direction of the rotator is effective. In particular, the rotator is a helical gear. In some cases, in addition to the above arrangement, it is desirable to arrange according to the helical angle of the rotating body.

As described above, in the rotation sensor according to the present invention, since one Hall element is formed on one semiconductor substrate, the mask pattern is determined by the size and shape of the rotating body. Type (size, etc.)
A single mask pattern suffices, irrespective of the variability. Further, it is not necessary to provide a dead space in the semiconductor substrate according to the interval between the teeth of the rotating body, so that the number of chips manufactured on one wafer can be increased.

In a die bonding process in a subsequent process (a process from assembling a chip as a final product to selecting / inspection), when arranging two Hall elements on a substrate, the size, shape, etc. Can be arranged at intervals according to the previous process (IC in the wafer)
It is possible to standardize the manufacturing process until the pattern is formed, and it is possible to effectively improve the productivity of the rotation sensor.

Further, the present invention is used for a rotation sensor for detecting at least the number of rotations of a rotating body having a plurality of teeth in a circumferential direction, and a magnetic detection IC for a rotation sensor disposed close to the rotating body. Wherein two Hall elements and an amplifier for amplifying a difference between output voltages of the two Hall elements are provided, and the two Hall elements and the amplifier are individually arranged on a substrate formed of a lead frame. The two Hall elements and the amplifier are sealed with a mold resin in a state where they are electrically connected to each other.

Thus, the mask pattern for forming the Hall element is not dependent on the type (size or the like) of the rotation sensor determined by the size or shape of the rotating body.
It requires only one mask pattern, and is versatile. Further, it is not necessary to provide a dead space in the semiconductor substrate according to the interval between the teeth of the rotating body, so that the number of chips manufactured on one wafer can be increased.

Further, for example, in the subsequent die bonding step, when the two Hall elements are arranged on the substrate, they can be arranged at intervals according to the size and shape of the rotating body. Therefore, the productivity of the rotation sensor can be effectively improved.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment in which a rotation sensor according to the present invention is applied to, for example, a rotation sensor for detecting a rotation speed and a rotation speed of a transmission gear in an automatic transmission of an automobile (hereinafter simply referred to as an embodiment). Will be described with reference to FIGS. 1 to 17.

As shown in FIG. 1, the rotation sensor 10 according to the present embodiment outputs, for example, two Hall elements H1 and H2 (see FIG. 2) for outputting a detection signal corresponding to a change in magnetic flux, and these two Hall elements. A magnetic detection IC 12 having a built-in amplification unit 200 (see FIG. 2) for amplifying a difference between output voltages of the elements H1 and H2, and each Hall element H of the magnetic detection IC 12
Magnetic circuit 14 for applying magnetic flux to H1 and H2
And a housing 16 that houses the magnetic detection IC 12 and the magnetic circuit 14.

The housing 16 is made of a synthetic resin, and a hole 22 of a wall 20 is formed in the transmission case 18.
Cylindrical first housing member 24 inserted through
A cylindrical second housing member 26 extending to one side along a wall 20 of the transmission case 18 from a rear portion of the first housing member 24, and a transmission case 18 from a rear portion of the first housing member 24;
Integrally has a mounting member 28 extending to the other side along the wall 20.

A metal cap 30 is fixed to the distal end of the first housing member 24 by, for example, caulking.

The housing 16 is provided with the magnetic detection IC 12
And a coupling portion (recess) 38 for connecting an output terminal plate 36 for taking out an electric signal from the magnetic detection IC 12 to the outside and an external circuit system. Have.

The recess 32 is provided in the first housing member 2.
The coupling portion 38 is formed from the front end of the second housing member 26 to the rear portion of the first housing member 24.

The rotation sensor 10 is mounted on the wall 20 of the transmission case 18 at the center thereof.
There is formed a through hole 40 through which a bolt member (not shown) for screwing is inserted.

The housing 16 has a first O-ring 50 for attaching a first O-ring 50 to a portion of the outer peripheral surface of the first housing member 24 which is in contact with the inner wall surface of the hole 22 of the wall 20 of the transmission case 18. Are formed, and a second annular groove 56 for attaching the second O-ring 54 is formed on the surface in contact with the cap 30.

The magnetic circuit 14 includes a magnet 60 for generating a magnetic flux.
And a yoke 62 for guiding the magnetic flux generated from the magnet 60 to the magnetic detection IC 12. And
The magnetic circuit 1 is provided in the recess 32 of the first housing member 24.
The magnetic detection IC 12 is inserted in the order of the yoke 62 and the magnet 60 that make up the magnet 4, and the front surface of the magnet 60, that is, the position facing the cap 30.

Therefore, when the transmission gear 64 in the transmission case 18 rotates, the magnetic flux applied to the two Hall elements H1 and H2 of the magnetic detection IC 12 changes, and from the Hall elements H1 and H2, for example, As shown in FIG. 5A, an AC signal (voltage signal) Vi1 having a frequency corresponding to the rotation speed of the transmission gear 64
And Vi2 are output.

On the other hand, as shown in FIG. 2, for example, the magnetic detection IC 12 is a GND substrate 100 made of a lead frame.
The first Hall element H1, the second Hall element H2, and the amplifying unit 200 are individually mounted thereon, and the GN
The entire circuit element including the D substrate 100 and the three terminals 102, 104 and 106 is sealed with a mold resin 108. Therefore, this molding resin 108
, Three terminals 102, 104 and 106 are led out.

These three terminals 102, 104 and 10
6, the terminal 104 at the center is a GND terminal, and FIG.
The upper and left terminals 102 are, for example, power terminals, and the remaining terminals 106 are output terminals. The three terminals 102, 104, and 106 are electrically connected to the output terminal board 36 (see FIG. 1) by soldering.

Here, the positional relationship between the two Hall elements H1 and H2 is, for example, as shown in FIG. 3, when the peak 64a of the transmission gear 64 faces one Hall element H1 and the other Hall element H2. The valleys 64b adjacent to the ridges 64a have a positional relationship such that they are substantially opposed to each other. That is, the first Hall element H1 and the second Hall element H
2 is set so that the pitch P between the gears 2 is approximately ２ of the tooth pitch of the transmission gear 64. Therefore, as shown in FIG. 5A, the voltage signals Vi1 and Vi2 output from the two Hall elements H1 and H2 have waveforms that are out of phase with each other.

The housing 16 made of synthetic resin is manufactured by insert molding so that the output terminal plate 36 is sealed in the housing 16.

As shown in FIG. 4, the amplifying section 200 mounted on the magnetic detection IC 12 has a power supply Vcc (for example, +5 V).
Power supply line 202 supplied through power supply terminal 102
And two amplifiers 204 and 206 for amplifying AC signals Vi1 and Vi2 (see FIG. 5A) output from the two Hall elements H1 and H2 with predetermined gains, respectively, and amplified AC signals from these amplifiers 204 and 206. aVi
1 and aVi2, a differential amplifier 208 that amplifies the difference with a predetermined gain to obtain a difference signal Vd (see FIG. 5B), and a difference signal Vd from the differential amplifier 208.
A trigger circuit 210 that compares d with a reference voltage (for example, a ground voltage) and shapes it into a trigger pulse signal Pv for operating a transistor circuit (amplifier 212) at a subsequent stage; and a trigger pulse signal Pv from the trigger circuit 210. It has, for example, an open-collector-type amplifier 212 that amplifies the output signal Vo (see FIG. 5C). Note that a comparator, a Schmitt trigger circuit, or the like can be used as the trigger circuit 210.

Here, an example of a method of manufacturing the magnetic detection IC 12 will be described with reference to FIGS. First,
As shown in FIG. 6, two types of semiconductor chips (a first Hall element H1, a second Hall element H2, and an amplifier 200) are manufactured in a process before the semiconductor chip.

Thereafter, as shown in FIG. 7, the first Hall element H1, the second Hall element H2, and the amplifier 200 are bonded to the die 222 of the lead frame 220 (die bonding step). In this die bonding step, the first and second Hall elements H
1 and H2 are fixed to the amplifying section 200 using, for example, a positioning device using a laser beam.
1, H2 and the amplification unit 200 are fixed on the die 222 using a silver epoxy paste.

Later, three terminals 102, 104 and 106
Frame portions 224, 226 and 228 are fixed by tie bars 230. This is because the frame portion 22 serving as the terminal in the die bonding step, the next wire bonding step, and the resin molding step is used.
4, 226 and 228 are not dispersed.

Thereafter, as shown in FIG. 2, the semiconductor device is put into a wire bonding step, in which the first Hall element H1 is connected to each terminal of the amplifier 200, and the second Hall element H2 is connected to the amplifier 20.
0, between the first Hall element H1 and the die 222,
Between the second Hall element H2 and the die 222, between the amplifier 200 and the die 222, between the amplifier 200 and each frame portion 224,
The wires 226 and 228 are electrically connected by wires 232 (wires of aluminum, gold, or the like).

Thereafter, as shown in FIG.
2. Circuit elements (each Hall element H1, H2 and amplifying unit 20)
0) is mounted in a resin molding process, and a die 222 and a circuit element (frame 1) including frame portions 224, 226, and 228 serving as three terminals are formed.
And the second Hall elements H1 and H2 and the amplifier 20
0) The whole is sealed with a mold resin 108.

Thereafter, the lead frame 220 is put into a cutting step, and the frame portions 224 and 22 serving as terminals of the lead frame 220 are formed.
6 and 228 are cut. The cutting position is, for example, a position slightly closer to the mold resin 108 from the tie bar 230 as shown by a two-dot chain line L in FIG. Of course, the tie bar 230 is connected to the frame portions 224, 226 and 22.
8 may be cut along the length direction. By performing this cutting process, as shown in FIG.
The magnetic detection IC 12 of the form from which the reference numeral 6 is derived is manufactured. At this point, as shown in FIG.
22 is a GND substrate 100 connected to the GND terminal 104
Will function as

As described above, in the rotation sensor 10 according to the present embodiment, the two Hall elements H1 and H2 and the amplifying section 200 are separately formed, and the GND substrate 10
Since the individual Hall elements are individually arranged on the semiconductor substrate, a configuration in which one Hall element is formed for one semiconductor substrate can be adopted. As a result, the mask pattern does not depend on the type (size, etc.) of the rotation sensor 10 determined by the size, shape, and the like of the transmission gear 64, and only one mask pattern suffices, resulting in high versatility.

Further, it is not necessary to provide a dead space in the semiconductor substrate in accordance with the interval between the teeth of the transmission gear 64, so that the number of chips (Hall elements) manufactured on one wafer can be increased.

In a die bonding process in a subsequent process (a process from assembling a chip as a final product to selecting / inspection), when disposing the two Hall elements H1 and H2 on the die 222, the transmission gear 6
4 can be arranged at intervals according to the size, shape, etc. of the rotation sensor 10.
Can be effectively improved.

Next, the rotation sensor 10 according to the present embodiment
The effect of the present invention will be described in comparison with a comparative example. In the comparative example, for example, as shown in FIG.
In this example, two Hall elements H1 and H2 are formed at 00.

First, when the configuration of the transmission gear 64 to be detected is a spur gear and its size is small, in the comparative example, as shown in FIG.
About 1/2 of the tooth pitch of the transmission gear 64
It is necessary to provide a dead space 402 corresponding to
As a result, there is a problem that the number of semiconductor chips that can be taken out from one wafer is reduced, and the yield is reduced.

On the other hand, the rotation sensor 10 according to the present embodiment
In FIG. 11, as shown in FIG. 11, the semiconductor chip 404 on which the first Hall element H1 is formed is separated from the semiconductor chip 406 on which the second Hall element H2 is formed. There is no need to provide a dead space 402 in the 406 as in the comparative example.
Semiconductor chips 404 and 40 that can be taken out of a single wafer
6 can be greatly increased, and productivity can be improved.

Next, when the configuration of the transmission gear 64 to be detected is a spur gear and its size is large, in the comparative example, as shown in FIG.
It is necessary to provide a very large dead space 408, and the size of the semiconductor chip 400 on which the two Hall elements H1 and H2 are formed inevitably increases.

As a result, the number of semiconductor chips 400 that can be taken out from one wafer is greatly reduced.
Productivity will decrease. That is, in the comparative example, there is a problem that the productivity is affected by the size of the transmission gear 64. In addition, since the amplifying unit 200 needs to be installed near the large semiconductor chip 400, there is a problem that the entire configuration of the magnetic detection IC 12 becomes very large.

On the other hand, the rotation sensor 10 according to the present embodiment
Then, as shown in FIG. 13, it is necessary to provide a large dead space 408 (see FIG. 12) in the semiconductor chip 404 on which the first Hall element H1 is formed and the semiconductor chip 406 on which the second Hall element H2 is formed. And these semiconductor chips 404 and 406 are
0 can be installed with the magnetic detection I
This is very advantageous for reducing the size of C12. Further, the length of the wire wired between each of the semiconductor chips 404 and 406 and the amplifying unit 200 can be shortened, so that the noise can be reduced, and the detection accuracy can be improved. Another advantage is that the productivity of the rotation sensor 10 is not affected by the size of the transmission gear 64.

Next, when the configuration of the mission gear 64 to be detected is a helical gear (helical gear), the installation positions of the first Hall element H1 and the second Hall element H2 are set in the horizontal direction (spur gear). In this case, it is necessary to incline the helical angle θ with respect to the direction determined by the installation position.

In the comparative example, since two Hall elements H1 and H2 are formed in one semiconductor chip 400, it is conceivable to prepare a mask pattern inclined at a helical angle θ, but it is economical. In consideration of such aspects, as shown in FIG. 14, it is more advantageous to adopt a method in which the magnetic detection IC 12 after resin molding is inclined by the helical angle θ.

However, since the housing 16 is manufactured by insert molding the output terminal board 36 (see FIG. 1), the position of the output terminal board 36 cannot be freely changed. It is necessary to incline by helical angle θ in accordance with IC12,
The coupling part 38 is also inclined by the helical angle θ.

In this case, it is very inconvenient especially when the present invention is applied to a mechanism in which various helical gears exist in a narrow space such as an automobile transmission and the direction of the coupling portion 38 cannot be freely set. There is a problem.

On the other hand, the rotation sensor 10 according to the present embodiment
In FIG. 15, as shown in FIG. 15, the first and second Hall elements H1 and H2 can be independently installed at the time of die bonding, so that the die 222 (GND)
The first and second Hall elements H1 and H2 can be easily changed in accordance with the helical angle θ without changing the direction of the substrate 100), that is, without changing the lead-out directions of the three terminals 102, 104 and 106. Can be installed in

In the example of FIG. 15, a line connecting the installation points of the first and second Hall elements H1 and H2 is indicated by an installation line m.
When the installation line when the detection target is a spur gear is particularly defined as a horizontal line n, the first and second angles are set so that the angle between the horizontal line n and the installation line m becomes the helical angle θ. The Hall elements H1 and H2 are connected to the die 222 (G
ND substrate 100).

Therefore, the present invention can be easily applied to a mechanism in which various helical gears exist in a narrow space such as an automobile transmission, and the direction of the coupling portion 38 cannot be freely set. This is also advantageous.

On the contrary, as shown in FIG. 16, when the configuration of the transmission gear 64 to be detected is a spur gear, the installation line m of the first and second Hall elements H1 and H2 is changed to a horizontal line. n and an arbitrary angle φ with respect to n, the first and second Hall elements H1 and H2 are connected to the die 222 (G
Consider the case where it is installed on the ND substrate 100).

In this case, as shown in FIG. 17, when the magnetic detection IC 12 is mounted, the magnetic detection IC 12 is mounted at an angle so that the installation line m coincides with the horizontal line n. At this time, three terminals 102,
104 and 106 are derived in a state where they are inclined by the angle φ between the installation line m and the horizontal line n on the die 222.

That is, when bonding the first and second Hall elements H1 and H2 to the die 222, three terminals 1
02, 104, and 106 can be freely determined, so that the directions in which the three terminals 102, 104, and 106 are derived, that is, the inclination of the coupling unit 38, depend on the installation conditions of the rotation sensor 10. Can be freely laid out, and the assemblability of the rotation sensor 10 is dramatically improved.

It should be noted that the rotation sensor and the magnetic sensor IC for the rotation sensor according to the present invention are not limited to the above-described embodiment.
Of course, various configurations can be adopted without departing from the gist of the present invention.

[0060]

As described above, according to the rotation sensor according to the present invention, the substrate having the lead frame
Since the two Hall elements and the amplifying unit are individually arranged and the two Hall elements and the amplifying unit are electrically connected to each other, the yield of the Hall elements can be improved, and the rotation speed can be improved. The arrangement of the Hall elements according to the size, shape, and the like of the body can be easily performed in, for example, a die bonding step in a later step, and the productivity of the rotation sensor can be improved.

Further, according to the present invention, in the above configuration, the two Hall elements are arranged at a predetermined interval in a direction along the rotation direction of the rotating body, so that the teeth of the spur gear are detected. As described above, the wiring length between each Hall element and the amplifying unit can be optimized, and it is possible to minimize the mixing of noise.

Further, according to the present invention, in the above configuration, when the rotating body is a helical gear, the two Hall elements are arranged at a predetermined interval in a direction along a rotating direction of the rotating body, and Since the arrangement is made in accordance with the helical angle of the rotating body, it is possible to detect the rotation speed of the helical gear with high accuracy.

Next, according to the magnetic detection IC for a rotation sensor according to the present invention, two Hall elements and an amplifying section are individually arranged on a substrate made of a lead frame, and
Since the three Hall elements and the amplifying unit are electrically connected to each other and sealed with a mold resin,
The yield of the Hall element can be improved, and the Hall element can be easily arranged in accordance with the size and shape of the rotating body, for example, in a die bonding step in a later step, thereby improving the productivity of the rotation sensor. Can be achieved.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a rotation sensor according to the present embodiment.

FIG. 2 is a diagram showing a configuration of the magnetic detection IC with a part cut away.

FIG. 3 is an explanatory diagram showing an arrangement relationship between two Hall elements.

FIG. 4 is a circuit diagram showing a configuration of circuit elements (first and second Hall elements and an amplifier) mounted on the magnetic detection IC.

5A is a waveform diagram showing an AC signal output from two Hall elements of the magnetic detection IC, FIG. 5B is a waveform diagram showing a deviation signal output from the differential amplifier, and FIG. FIG. 3 is a waveform diagram showing an output signal output from the amplifier.

FIG. 6 is an explanatory diagram showing two types of semiconductor chips (first and second Hall elements and an amplifying unit) manufactured in a process preceding the semiconductor chip.

FIG. 7 is an explanatory view showing a die bonding step.

FIG. 8 is an explanatory view showing a resin molding step.

FIG. 9 is an explanatory diagram showing a state in which a lead frame is cut into a magnetic detection IC.

FIG. 10 is an explanatory diagram showing an example of arrangement of circuit elements in a comparative example when the configuration of a transmission gear to be detected is a spur gear and the size is small.

FIG. 11 is an explanatory diagram showing an example of the arrangement of circuit elements in the magnetic detection IC of the present embodiment when the configuration of the transmission gear to be detected is a spur gear and its size is small.

FIG. 12 is an explanatory diagram showing an example of arrangement of circuit elements in a comparative example in a case where the configuration of a transmission gear to be detected is a spur gear and its size is large.

FIG. 13 is an explanatory diagram showing an example of the arrangement of circuit elements in the magnetic detection IC according to the present embodiment when the configuration of the transmission gear to be detected is a spur gear and its size is large.

FIG. 14 is an explanatory view showing a state in which a magnetic detection IC according to a comparative example is mounted in a partially broken state when a configuration of a transmission gear to be detected is a helical gear (helical gear).

FIG. 15 is an explanatory diagram showing a state in which the magnetic detection IC according to the present embodiment is mounted in a partially broken state when the configuration of the transmission gear to be detected is a helical gear (helical gear). .

FIG. 16 is an explanatory diagram showing an example of the arrangement of circuit elements on a die when the installation line is at an arbitrary angle with respect to the horizontal line when the configuration of the transmission gear to be detected is a spur gear.

FIG. 17 is an explanatory view showing a case where a configuration of a transmission gear to be detected is a spur gear, and a state in which a magnetic detection IC is attached is partially cut away when a terminal is drawn out at an arbitrary angle. FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Rotation sensor 12 ... Magnetic detection IC 14 ... Magnetic circuit 16 ... Housing 18 ... Transmission case 64 ... Transmission gear 100 ... GND board 102 ... Power supply terminal 104 ... GND terminal 106 ... Output terminal 108 ... Mold resin 200 ... Amplification part 232 ... Wire H1, H2 ...
Hall element

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Ichiro Ishikawa 1-4-1 Chuo, Wako-shi, Saitama Pref. Inside Honda R & D Co., Ltd. (72) Keiji Miura 1-4-1 Chuo, Wako-shi, Saitama Inside the Honda R & D Co., Ltd.

Claims (4)

[Claims] 1. A rotation sensor for detecting at least the number of rotations of a rotating body having a plurality of teeth in a circumferential direction, comprising: two Hall elements arranged close to the rotating body; An amplification unit for amplifying a difference between the output voltages of the two Hall elements and the amplification unit, respectively, on a substrate formed of a lead frame; Has a structure in which is electrically connected by wiring. 2. The rotation sensor according to claim 1, wherein the two Hall elements are arranged at a predetermined interval in a direction along a rotation direction of the rotator. 3. The rotation sensor according to claim 1, wherein when the rotating body is a helical gear, the two Hall elements are spaced from each other by a predetermined distance in a direction along a rotating direction of the rotating body. A rotation sensor, which is arranged according to a helical angle of the rotating body. 4. A magnetic sensor IC for a rotation sensor which is used in a rotation sensor for detecting at least the number of rotations of a rotating body having a plurality of teeth in a circumferential direction, and which is arranged close to the rotating body.
It has two Hall elements and an amplifying part for amplifying a difference between output voltages of the two Hall elements, and the two Hall elements and the amplifying part are individually provided on a substrate formed of a lead frame. Wherein the two Hall elements and the amplifying unit are sealed with a mold resin while being electrically connected to each other.