JPS5963539A - Torque detector - Google Patents

Abstract

PURPOSE:To detect torque applied to a torque transmission shaft by arranging two permanent magnets having numbers of magnetic poles on their circumferences on the torque transmission shaft at a specific interval, and detecting the composite magnetic field of magnetic fields produced by those two permanent magnets. CONSTITUTION:When no torque is applied because of the position relation between the magnetic pole array of the annular magnets 7 and 8 and an amorphous magnetic material ribbon 10, the N poles and S poles of the annular magnets 7 and 8 face each other, so when one terminal of the amorphous magnetic material 10 faces an N pole of the annular magnet 8, the other terminal of the amorphous magnetic material 10 faces an N pole of the annular magnet 8. The shaft 1 rotates and the N poles and S poles face both ends of the amorphous magnetic material 10 alternately. When torque is applied to the shaft 1, the magnetic poles of the annular magnets 7 and 8 shifts position corresponding to the value of the torque owing to the torsion of the shaft 1 and a difference in magnetic position between both ends of the amorphous magnetic material 10 is generated.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a l-lux detector, and more particularly to a torque detector that detects l-lux in a torsional direction applied to a torque transmission shaft.

Torsion occurs in the torque transmission shaft 1, for example, the shirt 1 that connects the output of the transmission and the propeller shaft, depending on the driving force and load. Therefore, by measuring the degree of this twist, it is possible to know the 1-rook applied to the torque transmitting shirt 1-.

Conventionally, the following method has been used for this type of torque detection.

(a) A strain gauge is fixed to the torque transmission shaft, and changes in the resistance value of the gauge caused by twisting of the shirts 1 to 1 are converted into electrical signals and detected.

(b) Two rotational signal generators that emit signals in response to the rotation of the shaft are placed a predetermined distance apart from each other, and the torsion of the shirt I- is determined from the phase difference between the signals obtained by the two signal generators. Detect.

However, in the former case, the mechanical strength of the gauge itself is small, and the resistance value changes (i.e., the output signal
Because of its small size, it has the disadvantage of requiring a highly sensitive amplifier, making it extremely difficult to use in some applications. Moreover, since it is necessary to attach the strain gauge directly to the shaft, special electrical connection devices such as slip rings and brushes are required to extract the signal in order to detect the 1 to 1 torque of the shirt 1-, which continues to rotate in one direction. is necessary. In addition, the latter method requires an electric circuit such as a complicated logic circuit for determining the phase difference of the signals, and has the disadvantage that it cannot be made small and one-to-one.

For example, in automobiles, it is necessary to detect a fairly large 1-lux, but there are few strain gauges that can detect large 1-lux, and there are many noise sources, so it is difficult to amplify the signal with a sufficient S/N ratio. Because of this, the strain gauge detects 1-lux every time. However, the smaller the size of this type of detector, the more preferable it is, and it is desirable that it can at least be integrated with the detected part. This type of detector also
It is desirable to have one that outputs a high-level signal without having to draw a long line so as not to be affected by sound.

The primary purpose of the present invention is to provide a compact torque detector that can be used even in applications that require durability, and also has a special purpose for extracting signals even when detecting the torque of a shaft rotating in a direction. The second objective is to provide a 1-lux detector that does not require a special mechanism, and the third objective is to provide a torque detector that can extract high-level signals with a high S/N ratio even in environments with many noise sources. The purpose of

In order to achieve the above object, in the present invention, two permanent magnet plates having a large number of magnetic poles formed on the circumference are placed on a torque transmission shaft with a predetermined distance apart, and the output of the two permanent magnet plates is Torque applied to the shaft is detected by detecting the composite magnetic field.

In other words, when the torque transmission shaft is twisted in response to the applied torque, the relative position (angle) between one permanent magnet plate and the other permanent magnet plate shifts accordingly. If we detect magnetism, we can detect the magnitude of 1-luk.For example, when 1-luk is a force of
If the pole and the south pole are opposed to each other, the difference in magnetic potential in the 1-axis direction of the 1-luke transmission shaft caused by the two magnetic poles becomes zero when the 1-luke is zero, but the difference in magnetic potential in the 1-axis direction becomes zero; When the shaft is twisted, an axial magnetic potential difference corresponding to 1-lux appears.

According to this arrangement, there is no need to fix the magnetic detection means to the 1-lux transmission shaft, and therefore no special mechanism is required to take out the signal.

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a one-herk transmission mechanism with an example one-luk detector. Referring to FIG. 1, reference numeral 1 indicates a 1-transmission output shaft 1 of an automobile, and normally a propeller shirt 1- is connected to the right side in the drawing.

Reference numeral 2 denotes a torque detector, which is constructed integrally with the shaft 1 and the bearing 3.

4 and 5 are sleeves placed over the shaft 1, and are fixed to the output shaft 1 by projections 4a and 5a formed at one end of each sleeve. The other ends of the sleeves 4 and 5 are movably supported by supports 6.

7 and 8 are annular magnets each having a large number of N poles and S poles alternately formed at equal intervals on the circumference. The annular magnetic door, the magnetic pole shapes and arrangement of 7 and 8 are the same,
In this embodiment, the positions of the N pole of the annular magnet 7, the N pole of the annular magnet 8, and the S poles of both magnets are adjusted so that they face each other, and then they are fixed to the sleeves 4 and 5, respectively. Inside the housing 9 of the torque detector 2, there is a shirt 1-
An amorphous magnetic ribbon 10 with both ends facing the magnetic poles of the annular magnets 7 and 8 in the axial direction of the magnet 1 is fixed to the amorphous magnetic ribbon 10.
1 is wound. A lead wire drawn out from the electric coil 11 is connected to a printed circuit board 12. An electric circuit, which will be described later, is constructed on the printer 1 to the substrate 12. 9a is a lid of the housing 9. Note that 13 is a gear that drives the speedometer.

Fig. 2a shows a plan view of the torque detector 2 of Fig. 1, and Fig. 2b shows the state where the rose 9a of Fig. 2a has been removed. Referring to FIGS. 2a and 2b, the printed circuit board 12 and M9a are fixed to the housing 99 with screws 4 and 15, respectively, and the housing 9 is connected to the bearing 3 with bolts 16. It sticks to. Printed circuit board】2
Glue-1-wires 17a, 17b and 1 from the electrical circuit above
7c is a drawer outside the housing sink 9 via the bushing J8.

3a and 3b schematically show the positional relationship between the magnetic pole arrangement of the annular magnets 7 and 8 and the amorphous magnetic ribbon [0. When no torque is applied, the N poles and the S poles of the annular magnets 7 and 8 are opposed to each other as shown in FIG.
When facing the ON pole, the other end of the amorphous magnetic body 10 faces the N pole of the annular magnet 8, but as the shirts 1 to 1 rotate, the N pole and S pole are formed at both ends of the amorphous magnetic body 10. The poles are alternately facing each other. When torque is applied to the shafts 1 to 1, the torsion of the shaft 1 causes a positional shift between the magnetic poles of the annular magnets 7 and 8 according to the magnitude of 1-lux. Therefore, when this positional shift occurs, the amorphous magnetic material 1
A difference occurs in the magnetic potential between both ends of 0.

The configuration of the electric circuit on the printed circuit board 12 in FIG.
As shown in the figure. The circuit shown in FIG. 4a is composed of a Royer oscillation circuit including the amorphous magnetic ribbon IO and the electric coil 11 wound around it, and an AC-DC conversion circuit consisting of a diode bridge and a smoothing circuit. Briefly, the Royer oscillation circuit oscillates due to the magnetic field applied to the amorphous magnetic ribbon 10, and an alternating current signal is obtained between the emitters of the transistors Qa and Qb.

The amplitude of this signal is proportional to the magnitude of the applied magnetic field,
The change occurs as shown in FIG. 4b. Therefore, a DC voltage proportional to the magnitude of the magnetic field is generated at the output terminal our of the AC-DC conversion circuit.

The magnitude of the magnetic field applied between both ends of the amorphous magnetic ribbon 10 is zero when the shirt 1-1 is not twisted (that is, no 1-lux is applied to the shirt 1-1); The potential of OUT becomes OV. When 1~l is applied to shirt 1~1 and 1 is twisted to shirt), the phase J position between annular magnet 7 and annular magnet 8 is displaced, and (
-The magnetic field proportional to the amorphous magnetic ribbon IO
is applied to Therefore, an output voltage corresponding to the torque is obtained at the output terminal OUT of the electric circuit.

Another embodiment of the invention is shown in Figures 5a and 5b. This will be explained with reference to FIGS. 5a and 5b. In this embodiment, an integrated circuit 19 incorporating a pole element is used as a means for detecting magnetism. integrated circuit 1
9 can output a signal at a sufficient level without adding any special electric circuit, so the printer 1 and board 12 are made very small and used as a terminal board for mounting. Further, since a rear amorphous magnetic material different from the previous embodiment is not used, the gap between the annular magnets 7 and 8 is made small, and the Hall element of the integrated circuit 19 is positioned in the gap between them.

In this embodiment as well, the fifth
As shown in Figure b, the N poles and S poles of the annular magnets 7 and 8 are opposed to each other.

In the above embodiment, the two sets of annular magnets 7°8 have the same polarity or are opposite to each other without the torque transmission shaft (1) being interposed so that the signal becomes zero when no torque is applied. However, if the shaft is not twisted and the two sets of annular magnets 7 and 8 are arranged so that they face each other with different polarities, the signal level will be maximum when the torque is zero, and the torque will increase. It is possible to configure a lux sensor having the characteristic that the signal level decreases as the value increases.

As described above, according to the present invention, since a complicated electric circuit is not required, the size can be reduced, and the torque detector can be integrated with a small mechanical element such as a bearing.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing the vicinity of a 1-transmission output shaft equipped with a torque detector according to an embodiment. FIGS. 2a and 2b are a plan view of the 1-lux detector 2 shown in FIG. 1 and a plan view showing the dispensing state with the lid 9a removed, respectively. Figure 3a shows the 1-lux detector 2 in Figure 1.
Fig. 3b is a plan view schematically showing a main part of the magnet, and Fig. 3b is a perspective view showing one annular magnet. FIGS. 4a and 4b are graphs showing the electrical circuit diagram and characteristics of the 1-lux detector 2 of FIG. 1, respectively. FIG. 5a is a longitudinal sectional view showing another embodiment, and FIG. 5b is a plan view of the main part of FIG. 5a. ■ = Transmission output shaft 2: 1-Lux detector 3: Bearing 4.5 Ni sleeve 4a+5a: Protrusion 6: Support 7: Annular magnet (first magnetic pole array) 8: Annular magnet (second magnetic pole array) 9: Housing 10: Amorphous magnetic ribbon 11: Electric coil (torque detector) 12 Niblint board 14, 15: Screw 16: Pole 1~17a, 17b, 17c: Riet wire 18: Push 19: Integrated circuit (1~Lux detector) ) Figure 2a Helmet 48 Figure 1 Figure 4b

Claims (5)

[Claims] (1) A first magnetic pole array fixed to a part of the torque transmission shaft, in which N poles and S poles are arranged alternately in the direction of the shaft; From the first magnetic pole array on the torque transmission shaft a second magnetic pole array having N poles and S poles arranged alternately in the circumferential direction, the second magnetic pole array being fixed to the 1-lux transmission shaft so as to face the first magnetic pole array at a predetermined distance apart; arranged within the magnetic field of the magnetic pole array and the second magnetic pole array,
Magnetic detection means: a 1-lux detector comprising: (2) The first magnetic pole array and the second magnetic pole array have one end connected to the i-
The other end of each sleeve is fixed to the torque transmission shaft. A torque detector according to claim (1). (3) The 1-lux detector according to claim (1), wherein the magnetic detection means is a Hall element. (4) The torque detector according to claim (1), wherein the magnetic detection means includes a magnetic body and an electric coil wound around the magnetic body. (5) The torque detector according to claim (4), wherein the magnetic material is an amorphous magnetic material.