JPS60175825A - Fixing method of drum in magnetic detecting encoder - Google Patents

Abstract

PURPOSE:To enable a stable output to be obtained from a sensor, by interposing an eccentric boss between a shaft and a magnetic drum so as to adjust a peripheral deflection of the magnetic drum, fixed to the shaft, to be decreased. CONSTITUTION:A magnetic drum 3, in order to adjust its deflection by interposing an eccentric boss 9, intentionally formed in an eccentric shape by eccentrically dislocating its internal and external diameters by a distance delta, between a shaft 2 and the magnetic drum 3 and rotating the eccentric boss leaving the magnetic drum as relatively fixed to the shaft, is fixed to the shaft from its end by a stopper screw 10. Then the eccentric distance delta, if the internal and external diameters of the eccentric boss 9 are dislocated by a distance 50-100mum, is sufficient as an adjusting margin, and the eccentric boss 9, if it is turned as much as half a turn, enables the peripheral deflection of the magnetic drum to be decreased to zero.

Description

[Detailed description of the invention] [The invention is based on the 111th version of the 111-purpose encoder.
41' is suitable for encoders having a drum-shaped cover and a φ projecting body). '3- That is, the detection body is fixed to the shutter 2 of the seven-torque J (the magnetic drum 3 has a magnetic qIXJ coated with a coating 1 consisting of a magnetic phase on its outer periphery, On its surface, a magnetic pole proportional to the encoder's power is magnetized.
! +'f1- Changes in magnetic flux caused by rain are detected by a magnetic sensor 5 fixed opposite to this, and a processing circuit converts the output multiplier into a waveform f (fi) as an encoder output.The processing circuit is connected to the board 6 and integrated with sensor 5)
At t, fix the fixing member 7 to the mold body side.

In a magnetically structured encoder having such a structure, the fluctuations of the sensor key V knob are caused by the deflection of the model shaft 2, the deflection of the drum 3, and the clearance between the shaft 2 and the mating part of the drum 30. If the accuracy of each individual component is not kept in check, the length gap will change greatly, and if it is extreme, it will become undetectable.Second
The figure shows the characteristics of the sensor gap' and sensor height output' tortoise pressure (relative value) when the magnetic pole's gradual magnetic pitch λ is used as a harameter. Even if the resolution is 400 to 600 P P t, Chengho's standard λ can be realized at 250 to 150 μm, but if the resolution is 1
If it exceeds 000PPl, λ will be less than 100μm,
The sensor gap range in which a stable sensor output voltage can be obtained becomes extremely small. Therefore, in order to realize an encoder with high performance, it is necessary to suppress fluctuations in the sensor gap even more severely. In other words, the surface resolution encoder will not work unless the 4n degrees and the combination precision jW of the H61+ product are managed 2 to 3 times more strictly.

[Purpose of the sixth light] The second purpose of the light is to provide a high-resolution IJ encoder by suppressing fluctuations in the sensor gap to obtain a stable sensor output pressure. It is in.

[J of invention! Earth - Chivalry] The present invention has the following features: 1. Yljl single coffin) regulation/silk combination 4#I
Since there is a limit to the improvement of AI, the accuracy remains at the conventional level, and by adjusting it by interposing 1 flat boss between Yanoto and 1 Liao Flea Drum, the l is finally identified on the shaft. This is an attempt to reduce the size of the outer drum of the 'ζ118 drum.

[Fruit of invention//iii example]

1・, Hon・(One implementation of Kushiri 1tall f:i@3
This will be explained using figures. Shaft 2, which was conventionally fitted directly
An eccentric boss 9 in which the inner and outer casings are intentionally eccentric by δ is interposed between the shaft end and the magnetic drum 3, as shown in FIG. 161 is fixed. The reason why we fix it from the shaft end with a set screw is because the eccentric boss can be moved around while the shaft and magnetic drum are fixed relatively to each other to adjust the deflection, so the 1ml from the lateral direction cannot be fixed as in the conventional method. It's only 1. The I-type is also more convenient than the conventional type in that it does not become eccentric due to force due to the clearance. If the eccentricity δ of the same outer diameter of the eccentric boss 9 is 50 μm to 100 μm, it is sufficient as an adjustment allowance.If the eccentric boss 9 is rotated half a turn, The blur can be reduced to 0.

〔Effect of the invention〕

According to the present invention, (1) Although the number of parts is 1 (since it is a pure part, the cost will not increase), the ejaculation of the cheap parts is as good as before, and the high It is possible to realize a high-performance encoder with a 1IIIi rating comparable to that of a standard encoder.

(2) With the drum fixing screw in one position, the gear does not move due to force, and stable 4-pod ejection is possible.

[Brief explanation of the drawing]

・Figure 1 is a vertical curved view showing the encoder structure of a conventional example, Figure 2 is a detection characteristic diagram of a sensor that uses a sensor gap with a 1-spoon pole pitch as a parameter, and Figure 3 is a diagram of the detection characteristics of a sensor that uses the sensor gap as a parameter. Encoder according to the invention 1) A vertical sectional view showing the construction of the encoder 1) Figure 4 is a sectional view perpendicular to the axis of the lower part of the shaft in Figure 3. 1...7-Tono 2...Modle/Gift, 3.
... Magnetic tram, 4... Magnetic film, 5... Magnetic sensor, 6... Substrate, 7... Fixing member, 8... Set screw,
9... Eccentric drum, $ 1 Fig. 2 m 0 5θ /l)

Claims (1)

[Claims] [A shaft 1 is formed by a circular member having an inner diameter inscribed in the shaft outer periphery and an outer diameter circumscribed in the inner periphery of the city air drum boss.
The drum of the magnetic detection type encoder with 11 (the drum is fixed between the front and the center of the shaft with a screw) (4 (foot method)).