JPH0224579A - Securing method of electric conduction of rotating shaft - Google Patents

Abstract

PURPOSE:To eliminate a disadvantage due to a potential difference between a rotating shaft and the outside by putting the rotating shaft in conduction to the outside through the intermediary of a needle being in contact with a pivot bearing element. CONSTITUTION:A rotating shaft 95 of a motor 94 is inserted in a noncontact manner into a hole 96 made in the central part of an electrostatic induction detecting plate 90. A conical pivot bearing element 97 is formed in the upper end part of the rotating shaft 95 of the motor 94, and the fore end part of a needle 99 formed of a conductor is brought into contact with the bearing element 97. The needle 99 is pressed downward by an elastic plate 100, while the elastic plate 100 is earthed by a conductor 101. When the motor 94 rotates, a shield plate 91 is rotated and therefore the detecting plate 90 having the same shape as the shield plate in a plan view is induced alternately by a charged body positioned below. Accordingly, a charging voltage is taken out as an alternating current matched with the amplitude thereof and is supplied to a motor processing element. Thereby a disadvantage due to a potential difference between the rotating shaft 95 and the outside is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application in Industry A] The present invention relates to a method for electrically conducting a rotating shaft used in a charged voltage sensor for OA type equipment and the like.

[Prior Art] The rotating shaft of electrical equipment, such as office automation equipment such as copy machines, facsimile machines, and computers, and rotating sector-type charged voltage sensors that detect the charged voltage of objects, is supported by bearings such as rolling bearings.

[Problems to be solved by the invention] In the equipment having the above-mentioned rotating shaft, the rotating shaft is insulated from external members such as the machine frame by the oil film of the bearing during operation, which often causes unfavorable performance problems. .

[Means for Solving the Problems] The present invention solves the above problems by providing a practically excellent electrical conduction method, that is, the electrical conduction method for a rotating shaft according to the present invention. is characterized in that a pivot bearing part is formed at the end of the rotating shaft 4), and by bringing a conductive fixed needle into contact with the pivot bearing part, electrical continuity is established with the outside via the needle.

[Operation] Since the rotating shaft is electrically connected to the outside via the needle that contacts the pivot bearing, no potential is generated between the rotating shaft and the outside.

[Example] Hereinafter, an example in which the present invention is applied to a rotating sector type electrostatic voltage sensor in a frictional electrostatic voltage measuring device for fabrics, etc. will be described.

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, and this Ff, friction voltage measuring device 1 includes a measuring device 2 that applies friction to a sample and measures the charged voltage, and a measuring device 2 that applies friction to a sample and measures the charged voltage. It is composed of a data processing device 3 that controls the operation of the printer and processes the obtained data, and a plotter 4.

As shown in FIGS. 2 and 3, the measuring device 2 measures the sample S.
The sample holding section 7 that holds the sample holding section 7 , the pedestal 9 , the friction device 10 , and the charged voltage sensor 13 are provided. The sample holding section 7 is
As shown in FIG. 4, it is equipped with a sliding sample table 16 provided with a circular hole I5 through which the surface of the sample S is exposed on the top surface, and a sample plate 17 to which the sample S is attached and fixed.
A sample plate 17 is placed on the side of the sample table 16.
The insertion port 19 for inserting is open. Further, inside the sample table 16, there are legs 22, . Pressing plates 24 and 24 are provided that press the sample plate 17 against the ceiling of the sample table 16 with a pressing force of... The entrance side portions of the press plates 24, 24 are inclined downward and face the insertion opening 19. The sample plate 17 has a circular hole 26 formed in the center of the plate bent in a stepwise manner, and when the sample plate 17 is mounted on the sample table 16, this hole 26 aligns exactly with the hole 15 on the table side. It's supposed to be. The sheet-shaped sample S is fixed under tension to the upper surface of the sample plate 7 using fixing means such as Scotch tape. Note that samples with low elasticity such as textiles and films can be measured by directly attaching them to the sample table 16 with tape or the like without using the sample plate 17. In addition, it is preferable to fix highly elastic samples such as knits with a plurality of bottles without using Scotch tape or the like.

The sample table 16 is integrally provided with a leg portion loosely fitted to the front end portion of the sample table 16, and rollers 33, 33 are attached to this leg portion. The rollers 33, 33 are adapted to move on a rail 34 provided directly below the groove 32 when the table 16 is moved. Further, a guide member 36 that extends horizontally is provided at the rear end of the sample table 16, and its tip is connected to the rail 40 within the groove 39 of the rising portion 37 provided in the main body case 30. It is designed to motivate people.

Pulleys 42 and 42' are provided at both ends of the rising portion 37 on the surface side.
A wire 43 is stretched between the stiff pulleys 42 and 42'. One end of the sample table 16 is locked to this wire 43.

The other pulley 42 is fixed to the rotating shaft of a pulse motor 45, and rotates as the motor rotates in the forward and reverse directions.
It is designed to move 3. When the wire 43 moves, the sample table 16 becomes grooved: 12. :19, the surface moves smoothly from the measurement position A to the friction position B. Note that the motor 45 is equipped with a rotary encoder 47.
is attached to detect the amount of rotation of the motor. The rotary encoder 47, which is a means for detecting the amount of rotation of the rotary motor 45 and the rotary motor, is connected to the data processing device 3, which also serves as a control device.

The pedestal 9 is made of wood and has a cylindrical shape with a smooth upper end, and is supported by a rod 53 attached to the core 52 of the solenoid 50 as shown in FIG. core 52
is normally pulled down by the spring 55, but moves up when the solenoid is energized, and the receiver 9 moves up and down in accordance with this action. When the pedestal 9 is in the lowered position,
Sample S with its L side set on the sample table 16
, but is adjusted so that it lightly touches the back surface of the sample S when the solenoid 50 is energized and is in the raised position. This solenoid 50 is also connected to the data processing device.

As shown in FIG. 6, the friction device 10 includes a crank mechanism in which a bin 59 is eccentrically provided on a rotary table 57, and a swinging arm 62 having an elongated hole 60 into which the bin of the crank mechanism is slidably fitted. In addition, there is a cylinder 63 at the base of the swinging arm.
are integrated. The cylinder 63 is rotatably fitted to the support shaft 64, and the upper end of the cylinder 63 is connected to the support 11!
It is pressed downward by a coil spring 65 fitted onto the dI64. The strength of the pressing force of the coil spring 65 can be adjusted as appropriate with a nut 66 screwed onto the threaded portion 64a at the top of the support shaft 64.

A protrusion 69 having an inclined surface 69a at the end is integrally provided on the lower surface side of the swinging arm 62.
A roller 70 provided at 7 pushes up this protrusion 69 at a predetermined rotational position of the rotary table. That is, as the rotary table 57 rotates in the direction of arrow Y, the swing arm 62 is rotated in the direction of arrow X and anti-X by the crank mechanism.
However, when moving in the direction of arrow X, the roller 70 comes off the protrusion 69, so the swinging arm 62 is pushed down by the coil spring 65, and when moving in the counter-X direction, the swinging arm 62 is pushed down by the coil spring 65. 62 is lifted by rollers 70. When the swinging arm 62 is lifted, the a! When the sliding pad 11 is lifted from the sample surface and the swing arm 62 is lowered, the pad I+ comes into contact with the sample surface. Therefore, the pad 11 rubs against the sample surface only when moving in the direction of the arrow X, and separates from the sample surface when returning in the opposite direction. In addition, a! The Sakekin Bad 11 is made by packing 5 to 10 g of absorbent cotton into a rectangular main body, covering it with washed gold cotton cloth or wool, and fixing it with rubber bands, adhesive tape, etc., giving it the appearance of a blackboard eraser. have This pad 11 is attached to a stepped tip 72 of the swing arm 62 with a screw 73. It is easy to attach and detach.

A bevel gear 76 is attached to the rotating shaft 75 of the rotating table 57.
is fixed, and a hevel gear 79 of a pulse motor 77 meshes with this bevel gear 76. This motor 77
A rotary encoder 80 is also attached to the rotary encoder 80, and the rotary encoder 80 is connected to the data processing device 3.

The charged voltage sensor 13 is arranged so that it is located just above the sample when the sample table 16 is located at the measurement position A.
It is attached to the tip of a support case 83 attached to a shaft 82 provided on the rising portion 37 of the main body case. This sensor 13 is a rotating sector type sensor, and as shown in FIG. 7, a sector-shaped electrostatic induction detection plate 90 and a shielding plate 91 of the same shape as the detection plate are provided vertically at intervals. The electrostatic induction detection plate 90 located on the upper side is fixedly supported by an arm 92, and the shielding plate 9■ located on the lower side is attached to a rotating shaft 95 of a brushless motor 94. A rotating shaft 95 of the motor 94 is inserted into a hole 96 formed in the center of the electrostatic induction detection plate 90 without contacting it. motor 94
A bell-shaped pivot bearing part 97 is formed at the upper end of the rotation lllllI95, and the tip of a needle 99 made of a conductor is in contact with this pivot bearing part 97. This needle 99 is pressed downward by an elastic plate +00, and the conductive elastic plate +00 is grounded by a conducting wire +01. Charge voltage sensor 13
With the charged sample S positioned directly below the motor 9
When the shielding plate 4 rotates, the shielding plate 91 rotates, so that the detection plate 90, which has the same shape in plan view, may or may not be dielectrically charged by the charged body below. Therefore, the charged voltage is taken out as an alternating current commensurate with its magnitude, amplified by the preamplifier, and supplied to the data processing section. In a bearing such as a rolling bearing, as the shaft rotates, an oil film is formed on the surface of the rolling body (pole or roller), and the bearing rolls through this. For this reason, the shaft and the outer side of the bearing have high electrical resistance, and the shielding plate is not completely grounded, so that the rotating shielding plate has a potential. Furthermore, since the high resistance on the outside of the shaft and the bearing fluctuates as the shaft rotates, the shaft potential also changes, thereby inducing noise in the electrostatic induction detection plate. Although there is a possibility that measurement accuracy may be reduced due to this influence, in this device, since the rotating shaft 95 of the motor 94 is grounded via the needle 99, measurement errors due to the causes listed in -F do not occur.

Directly below the charged voltage sensor 13, as shown in FIG. 3, a disc-shaped calibration electrode 110 having the same shape as the hole I5 of the sample table 16 is provided so as to be movable up and down.

The calibration electrode +10 is connected to a high-voltage power supply circuit for calibration that can load a constant charged voltage, and is normally pulled in to the -F surface level of the main body case 30, but when the electrode raising lever Ill is operated. By this, the charged voltage sensor 13
can be raised to a predetermined height approaching . This calibration electrode 110 allows the sensitivity of the charged voltage sensor 13 to be calibrated.

The data processing device 3 is configured as shown in FIG. That is, the synchronization signal from the motor 94 of the charged voltage sensor 13 and the charged voltage analog signal from the preamplifier +21 are
A/D converter 12 including a motor synchronization signal detection circuit 120, a main amplifier 122, and a one-chip microcomputer 123
5, and the digital signal from the A/D converter is supplied to an arithmetic unit (computer) +26. Arithmetic unit 12
In step 6, the measurement data is processed, and the results are displayed on the display! 27 and plotter 4.

The calculation unit 128 also includes a motor 45° solenoid 50 of the measuring device 2. A control relay part +30 for driving the motor 77 and the like is connected to a setting switch group +31, so that the operation of the entire apparatus can be controlled, measurement conditions can be set, etc. Note that the calibration high-voltage power supply 133 is connected to the calibration electrode +10 as described above. 1 in the diagram
35 is a power supply circuit connected to AClooV to obtain a constant DC voltage.

As shown in Fig. 9, the plotter 4 records the change in the charged voltage of the sample over time in a graph, and also records the peak voltage in the - measurement at the recording position +40 above each graph, for example, at -3, 42V. Record it as follows. In the same figure,
The vertical axis is the charged voltage, and the horizontal axis is time (seconds or minutes). This coordinate scale is also drawn as a chart on the recording paper P by the plotter 4 according to setting conditions. In addition, when one sample is measured the tth set number of times (for example, 5 times), the average peak value, the fluctuation rate of the peak value, and the time after the first set time (for example, 10 seconds) have elapsed since the start of measurement. The average and fluctuation rate of the charge value, the second set time (e.g. 3
0 seconds), the average and fluctuation rate of the charge value after the elapse of 0 seconds, if necessary,
Furthermore, the statistical processing results such as the average and fluctuation rate after the n-th set time elapse, the average half-life and fluctuation rate, etc. are displayed in the right column 1 of the chart.
It is designed to be recorded along with 41. in this way,
Since the measurement data is statistically processed and displayed at the same time,
It is extremely convenient in practice.

Recording of each measurement data by the plotter 4 is performed by sampling the data at predetermined time intervals and plotting it on recording paper, but as shown in Figure 9, the change in the charge value immediately after the start of recording is particularly rapid. Therefore, the sampling interval of the plotter is made shorter (for example, 1/2) for a predetermined period of time (for example, 10 seconds) from the start than for the subsequent portion (for example, 1/2). For this reason, it is able to fully adapt to sudden changes in data and draw a graph with a high degree of rust.

Next, how to use this frictional charge voltage measuring device 1 will be explained with reference to the flowchart showing the measurement operation shown in FIG.

First, a sample cut into a substantially square shape is placed on the sample plate 17 so as to cover the hole 26, and fixed with Scotch tape. At this time, make sure that there are no wrinkles on the sample surface.

Insert the sample plate 17 with the sample attached into the insertion opening 19 of the sample table 16, and push it in so that both holes 15 and 26 overlap.

After confirming that the power of the measuring device 2 is turned on, turn on the power of the data processing device 3 and plotter 4, and turn on the buzzer +
Wait until 50 rings. This buzzer indicates whether the plotter 4 is ready or not, and when this buzzer goes off, the measuring device 2 is turned on. Thereafter, each switch in the setting switch group, such as a voltage range setting switch, a measurement count setting switch, a measurement time setting switch, etc., is selected and set. When performing calibration, a calibration switch is operated to perform the calibration operation described below, but normally calibration is not necessary.

Once the above settings have been made, the plotter 4 is used to draw chart plots along the X and Y axes on the recording paper P.

When the start switch of the measuring device with the sample set is turned on, the sample table 16 moves to the friction position B, the pedestal 9 rises to support the back side of the sample, and the friction pad H of the friction device IO moves the sample table 16 to the friction position B. The sliding friction is performed a predetermined number of times (for example, 12 times). When the friction is finished, the pedestal 9 is lowered one step, the sample table 16 returns to the measurement position A, and the charged voltage is detected by the charged voltage sensor 1. This detection signal is processed by the data processing bag j43 and recorded by the plotter 4. After this operation is performed a set number of times (for example, 5 times), the obtained statistical values are printed. After completing a predetermined number of measurements for one sample, repeat the same measurements using a different sample.

Next, the method for calibrating the charged voltage sensor will be described. First, the sample plate 17 is removed from the sample table 16 at the measurement position A, and the lever 111 is pulled up to raise the calibration electrode 110 to the position of the hole I5. In this state, a predetermined calibration voltage (e.g. -5kv) is applied to the calibration electrode, and detection is performed by the charged voltage sensor 13. This detection result is recorded by the plotter 4, but the value deviates from the set voltage. If so, adjust the sensitivity and calibrate.

[Effects of the Invention] As is clear from the above description, the method of electrically conducting a rotating shaft according to the present invention provides electrical connection to the outside via a pivot bearing formed at the end of the rotating shaft and a needle that contacts the stiffness. Since the rotating shaft is electrically connected to the outside, there is no insulation between the rotating shaft and the outside, and problems caused by potential differences between the rotating shaft and the outside do not occur.

Note that since the contact area between the pivot bearing and the needle is small, an oil film is unlikely to form on the contact area.

[Brief explanation of the drawing]

Fig. 1 is an external view of one embodiment of the present invention, Figs. 2 and 3 are perspective views of the measuring device in different states, Fig. 4 is a perspective view of the sample holding section, and Fig. 5 is a receiving part. An explanatory diagram of the stand, Fig. 6 is an explanatory diagram of the friction device, Fig. 7 is an explanatory diagram of the charged voltage sensor,
FIG. 8 is a block diagram showing the overall configuration, FIG. 9 is an explanatory diagram of the contents recorded by the plotter, and FIG. 10 is a flowchart of the operation. 1... Hokkaido charged voltage measuring device 2... Measuring device 3...
・Data processing device 4...Plotter 7...Sample holder 9...Case lO...a! Rubbing device Eye...Sliding friction bat 13...Charged voltage sensor 16...Sample table 17...Sample plate

Claims (1)

[Claims] (1) Rotation characterized by forming a pivot bearing at the end of the rotating shaft, and bringing an electrically conductive fixed needle into contact with the pivot bearing to establish electrical continuity with the outside via the needle. Electrical conduction method of shaft.