JPH05126883A - Calibration device of particle electric charge measuring equipment - Google Patents

Abstract

PURPOSE:To obtain a particle electric charge measuring equipment which can calibrate an actual measurement value of a particle electric charge measuring equipment more accurately without causing conductive particles which are dropped from a dropping port of a particle pad to contact a measuring tube part of the particle electric charge measuring equipment. CONSTITUTION:A calibration device 1 of a suction-type Faraday cage 10 is constituted of a funnel part 6 and a straight-pipe part 7 which is formed in a straight-pipe shape in vertical direction and is provided with a particle pad 5 for keeping a specified amount of conductive particle 2, a cylindrical grounding electrode 3 which opposes the straight-pipe part 7, and a power-supply device 18 which applies a specified voltage between the grounding electrode 3 and the particle pad 5. A dropping port 4 at a tip of the straight-pipe part 7 is placed at a position which substantially passes through the axis of a measurement pipe part 17a. Therefore. the conductive particles 2 which are dropped from the dropping port 4 do not contact an inner wall of the above measuring pipe part 17a and can calibrate a measurement value which is measured by a suction-type Faraday carve 10 extremely accurately.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calibrating device for correcting a measurement error of a measuring instrument for measuring a charged electric charge of a conductive powder such as a developer used in a copying machine or the like.

[0002]

2. Description of the Related Art Basics for measuring the amount of electrified charge of conductive powder
As a typical device, a standard Faraday cage as shown in Fig. 4 is used.
There is page 12. This is a grounded shield conductor 16
Insulated conductor container 17 is placed inside the
The powder 2 is placed in the conductor container 17, and the opening 17 of the shield conductor is formed._c
Grounding of the conductor container 17 when passing through without contact
The inter-potential is measured by the electrometer 8. This reference file
That the Laday cage 12 is a practical charge measuring device
Then, the suction type Faraday cage 10 shown in FIG.
There is a blow-off device 11 shown in FIG. However, above
Suction type Faraday cage 10, blow-off device
Depending on the difference in the equipment configuration of each measuring device such as the storage device 11,
Even though there is an error in the measured load value, this
There was no good way to calibrate. So, for example, electronic
In fields such as photography, research and development of developers such as toner
And quality control, or by standardizing the charge amount value
There was inconvenience in clarifying it. Therefore, products such as developers
Inviting quality instability and improving the reliability of product quality
I couldn't. Therefore, the present inventors have described above.
To solve the problem, the calibration device 1 shown in FIG. _aDevelop
However, prior to the present invention, Japanese Patent Application No. 3-105393
Applied. Calibration device 1 for the powder charge measuring instrument_aBye
For example, if the powder receiver 25 is inclined by an angle θ with respect to the horizontal plane,
A high voltage from a power supply device (not shown) is connected to the ground electrode 23.
Conductivity stored in powder receiver 25 with voltage applied
When dropping the conductive powder 2 little by little from the powder receiver 25,
The applied high voltage causes the conductive powder 2 to have a fixed amount of electricity.
It takes a load and falls. Fixed in the powder receiver 25
In order to drop the amount of conductive powder 2 little by little,
A vibrating element 26 (powder dropping means) is attached to a required portion of the scale 25.
The powder receiver 25 is attached by the vibrating element 26.
Shake and drop the conductive powder 2 little by little by this vibration.
It is designed to be sieved off from No. 4. The powder receiver 25
The conductive powder 2 contained in the
It is relatively small, and the inclination of the powder receiver 25 with respect to the horizontal plane
The angle θ is also relatively small enough to accommodate this conductive powder 2.
Since it is a small angle, the guide dropped from the above drop port 24
The horizontal inertial force of the electric powder 2 is small and
It falls in the direction close to the direct direction. Such a calibration device 1_aIs based
It is supported by a column 22 standing upright on a board 27 so as to be movable up and down.
And the powder charge measuring instrument to be calibrated is installed on the base 27.
Then, a certain amount of electrically conductive powder 2 is dropped into it.
To be done.

[0003]

[SUMMARY OF THE INVENTION However, in the calibration apparatus 1 _a, receiving suction type Faraday cage 10 and the blow-off device 11 and the powder which is placed on the base 27 2
5, the conductive powder 2 dropped from the dropping port 24 may be the inner wall of the measuring tube portion _17a (FIG. 6), _17b (FIG. 7) of each charge measuring device. May come into contact with. Thus, when the conductive powder 2 given a predetermined charge amount is in contact with the measurement pipe section 17 _a, 17 _b,
Can not be carried out properly calibrated by each powder charge measuring instrument measurement error accurately calibrated to so created has been the calibration apparatus 1 _a. Therefore, an object of the present invention is to perform more accurate calibration without the conductive powder dropped from the drop port of the powder receiver coming into contact with the measuring tube portion of the powder charge measuring instrument. It is to provide a calibration device for a powder charge measuring instrument.

[0004]

In order to achieve the above-mentioned object, the present invention is to charge charged conductive powder into a conductor container shielded by a ground conductor and to charge the conductive container and the ground. In a calibration device for a powder charge measuring instrument, which applies a given charge amount to a given amount of conductive powder, puts it into the measuring tube section of the powder charge measuring instrument that measures the amount of charge per contact. A powder receiver for containing the powder, a powder dropping means for dropping the conductive powder contained in the powder receiver little by little, and a ground electrode provided at a position close to the dropping port of the powder receiver. And a power supply device for applying a predetermined voltage between the ground electrode and the powder receiver, wherein the dropped conductive powder is placed at the tip of the drop port of the powder receiver. It is characterized in that it is arranged at a position that passes through the shaft core. Further, in the configuration of the invention described above, the tip of the dropping port of the powder receiver may be formed in a vertical straight tube shape.

[0005]

According to the present invention, the quantified amount of the conductive powder 2 is added to the powder charge measuring instrument to be calibrated from the calibration device equipped with the power supply device for applying the predetermined amount of electric charge to the predetermined amount of conductive powder. Can be supplied by giving a fixed amount of electric charge. Moreover, the conductive powder dropped from the tip of the dropping port does not come into contact with the measuring pipe portion because it passes through the substantial axis of the measuring pipe portion of the powder charge measuring instrument. Therefore, if the measured value of the amount of electric charge of the powder charge measuring instrument to be calibrated at that time is compared with the value measured by the reference Faraday cage, and the error is calibrated in advance for each charge measuring instrument, Even if the charge amount of the above-mentioned conductive powder is measured using a charge measuring device, an extremely correct measured value can be obtained. That is, the conductive powder used in the calibration device is brought into contact with and housed in a powder receiver, for example, as an electrode, to which a predetermined voltage is applied by the power supply device, so that the conductive powder has the same potential as the electrode. Therefore, in the constant electric field formed between the opposing ground electrode and the electrode to which the predetermined voltage is applied, the conductive powder particles are separated from the powder receiver to which the predetermined voltage is applied by separating from the powder receiver. A charge commensurate with the capacitance will be given. Therefore, by using the above-mentioned conductive powder to which a fixed amount of electric charge has been applied to the measuring tube part of the powder charge measuring instrument to be calibrated without contact, it can be used as an extremely excellent reference material for calibration. You can

[0006]

Embodiments of the present invention will now be described with reference to the accompanying drawings.
Examples will be described to provide an understanding of the present invention. In addition,
The following example is an example of embodying the present invention.
It does not limit the technical scope of Ming. Figure 1
Shows the schematic configuration of the calibration device according to the present invention and the installation of this calibration device.
Figure 1 shows a suction Faraday cage installed and in schematic side section
Configuration diagram, Figure 2 shows the above calibration device and this calibration device installed
Blow-off device and a schematic side sectional view, FIG.
Reference Faraday cage and suction Faraday cage or
It is a graph which shows the comparative measurement example with a low-off apparatus. However
However, the reference Faraday cage 12 shown in FIGS.
With suction type Faraday cage 10 and blow-off device 11
For common components, use the same symbols
The detailed description is omitted here. Calibration according to this embodiment
The device 1 is, as shown in FIG. 1, a funnel part having a funnel-shaped cross section.
6 and the vertical formed by connecting to the lower end opening of the funnel portion 6
Consisting of straight pipe part 7 with axial direction axis
Conductor powder receiver 5 for containing powder 2 and conductive and cylindrical
Is formed in a shape and has electrical insulation on its top, for example
Of the powder receiver 5 via the insulator 13 made of synthetic rubber.
It supports the straight pipe portion 7 and is paired with the dropping port 4 at the lower end of the straight pipe portion 7.
The grounding electrode 3 that is polarized, the grounding electrode 3 and the powder receiver 5
And a power supply device 18 that applies a predetermined high voltage between
It is mainly composed. In particular, the straight pipe of the powder receiver 5
The portion 7 penetrates the insulator 13 coaxially with the ground electrode 3 described above.
Is supported and therefore the tip of the drop port 4 of the powder receiver 5
Will be located at the axis of the ground electrode 3. In the figure
Then, the calibration device 1 having the above-mentioned configuration is a suction type Faraday cage.
Measuring pipe part 17 which is vertically installed in 10_aTop edge of
The straight pipe portion 7 is the measurement pipe portion 17 _aAnd almost coaxial core
It is installed in a position where Such straight pipe part 7 and measuring pipe
Part 17 _aThe arrangement relationship with the blow-off device 1 shown in FIG.
1 measuring tube section 17_bAnd the standard Faraday cage shown in Fig. 4
12 shield conductor openings 17_cAnd the straight pipe section 7
The same applies to the arrangement relationship. In addition, the straight pipe section 7
The inner diameter is such that the conductive powder 2 contained in the funnel portion 6 is dropped into the dropping port 4
The diameter is set so that it can be dropped little by little. That is, above
The straight pipe portion 7 of the powder receiver formed with a predetermined inner diameter is
For dropping conductive powder put in a body receiver little by little
It is an example of a powder dropping means according to the present invention.

Therefore, the calibration device 1 having the above-mentioned configuration is used.
The method of calibrating each powder charge measuring instrument will be described below.
First, the calibration device 1 has a reference Faraday cage 12
It is installed on the upper surface of Fig.
The powder receiver 5 with a predetermined amount of conductive powder
2 are accommodated. In the powder receiver 5, the funnel part 6
The stored conductive powder 2 is charged until the measurement of the charge amount is started.
Is stored in the funnel part 6 by a fall prevention mechanism (not shown).
It is still there and is prevented from falling from the drop port 4 above.
There is. Therefore, the calibration device 1 uses the powder receiver 5 with a fixed
A predetermined charge is applied to the amount of the conductive powder 2 by the power supply device 18.
While giving this conductive powder 2, the Faraday cage 16 (Fig.
4) Drop inside and guide the Faraday cage 16 at that time.
The ground potential of the body container 17 is measured by the electrometer 8. This base
Conductive powder 2 measured by quasi-Faraday cage 12
Of the charge amount per unit weight of the powder receiver 5 and the ground electrode 3
The relationship with the applied voltage is as shown in FIG. This
, Measured by the above standard Faraday cage 12
The relationship between the measured charge amount Q and the amount x of the conductive powder 2 dropped
It is shown by the solid straight line of 3. In the figure, for example, conductive
Q is the measured value of the amount of charge when the amount x of powder 2 dropped is a.₁When
Then, this is the reference value for calibration of the measured value of each powder charge measuring instrument.
Becomes Continuing, the suction type Faraday cage shown in Fig. 1
10 (Measuring instrument A), the above standard Faraday cage
The same charge amount as in the case of No.
Of electric charge when conductive powder 2 is dropped by applying
The value is Q based on the linear relationship shown by the broken line in FIG.₂Met
At this time, the calibration value QA of this measuring instrument A is QA = (Q₁/
Q₂) ・ It can be expressed by the calibration formula of Qa, and it is measured at the time of actual measurement.
The value Qa is calibrated to the measured value of the above standard Faraday cage 12.
To be done. The above measured value Qa is the suction type Faraday cage 1
0 (measuring device A) was used, and
Suck the one-component developer from the developing roller (not shown) of the copying machine.
Is a value obtained by measuring the charge amount of. Moreover, the measuring instrument B is shown in FIG.
This is based on the blow-off method as shown below.
The measured value Qb at the time of actual measurement by the measuring device B is shown by the one-dot chain line in FIG.
Q based on a linear relationship ₃Even if it was, the above measured value Q
b is calibrated against a reference value as described above. This measurement
The calibration value QB of the instrument B is QB = (Q₁/ Q₃) ・ Qb school
It can be officially expressed. The measured value Qb is shown in FIG.
Using the blow-off device 11 (measuring instrument B), actually
Remove the two-component developer from the developer in the copier using the developer.
It is the value measured by the protrusion. Therefore, according to the above calibration device 1,
In this way, the same unified measurement can be made with any kind of measuring instrument.
You can get a fixed result. Moreover, the embodiment of the present invention
According to the arrangement, the tip of the dropping port 4 of the powder receiver 5 is
Conductive powder 2 dropped from each is a powder charge measuring device
Measuring tube part 17_a, 17_bOr opening of shield conductor
Part 17_cIs located at a position that passes through the axis of
Then, the dropped conductive powder 2 is added to each measuring tube portion 17_a，
17_bAlternatively, the opening 17 of the shield conductor_cContact with
It is possible to calibrate the measured values extremely accurately.
Wear. Also, the conductive powder 2 is formed into a straight tube in the vertical direction.
From the drop port 4 at the tip of the straight pipe portion 7 of the formed powder receiver 5
Since it is dropped, it drops vertically from the time it is dropped.
It Therefore, the conductive powder 2 is passed through the substantially axial core of the measuring tube section.
The calibration device 1 and each powder charge measuring device
The positional relationship can be easily set.

[0008]

As described above, according to the present invention,
Since it is possible to calibrate a constant amount and a constant charge amount of conductive powder under the same conditions for any powder charge measuring device, it is possible to accurately calibrate the actual measurement value of each measuring device. .. In addition, the dropped conductive powder does not come into contact with the measuring tube portion of the powder charge measuring device or the opening of the shield conductor, for example, so that the measured value can be calibrated more accurately. By calibrating the powder charge measuring device with this calibrating device, the charge amounts of the conductive powder measured by each calibrated measuring device are compared with each other, and the performance comparison of these conductive powders is performed. As a result, for example, it will make a great contribution to research and development of toner in electrophotography and quality control of products. In addition, the quality of powder products such as the toner and the like can be clearly specified and standardized.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a schematic side view of a schematic configuration of a calibration device according to the present invention and a suction-type Faraday cage in which the calibration device is installed.

FIG. 2 is a configuration diagram schematically showing a cross-section of the calibration device and a blow-off device in which the calibration device is installed.

FIG. 3 is a graph showing a comparative measurement example of a reference Faraday cage and a suction type Faraday cage or a blow-off device.

FIG. 4 is an explanatory diagram showing a method of calibrating a reference Faraday cage by a conventional calibration device.

FIG. 5 is a perspective view showing a configuration of the conventional calibration device.

FIG. 6 is an explanatory diagram showing a method of calibrating a suction type Faraday cage by the above-described conventional configuration device.

FIG. 7 is an explanatory view showing a method of calibrating a blow-off device by the above-mentioned conventional calibrating device.

FIG. 8 is a graph of a measurement example using a reference Faraday cage.

[Explanation of symbols]

1, 1 _a ... Calibration device 2 ... Conductive powder 3 ... Ground electrode 4 ... Drop port 5 ... Powder receiver 6 ... Funnel part 7 ... Straight pipe part 10 ... Suction-type Faraday cage 11 ... Blow-off device 12 ... Reference Faraday Cage 13 ... Insulation part _17a , _17b ... Measuring tube part _17c ... Shield conductor opening 18 ... Power supply device

Claims (2)

[Claims] 1. A measuring tube part of a powder charge measuring instrument for charging charged conductive powder into a conductor container shielded by a ground conductor to measure the charge amount per charged amount between the conductor container and ground. In a calibration device for a powder charge measuring instrument, which applies a predetermined charge amount to a predetermined amount of conductive powder, and puts it in a powder receiver into which a predetermined amount of conductive powder is placed, and into the powder receiver. A powder dropping means for dropping the conductive powder little by little and a ground electrode are provided at a position close to the dropping port of the powder receiver, and a predetermined voltage is applied between the ground electrode and the powder receiver. A powder comprising a power supply device for applying a voltage, and the tip of the dropping port of the powder receiver is arranged at a position where the dropped conductive powder passes through substantially the axis of the measuring tube section. Charge meter calibration device. 2. The calibration device for a powder charge measuring instrument according to claim 1, wherein the tip of the dropping port of the powder receiver is formed in a vertical straight tube shape.