JPS608758A - Measuring device of electric charge distribution of toner particle - Google Patents

Abstract

PURPOSE:To introduce toner particles, which are required for one measurement, at a time by providing an electrode, which generates an alternating electric field, in the flow passage of toner particles which are discharged to the outside of a developer vessel and go toward a suction tube and constituting a means which introduces toner particles to the suction tube of an electric charge distribution measuring device. CONSTITUTION:Toner particles are separated from a developer in a developer vessel 51 and start dropping by the action of a blow-off device 50 consisting of the developer vessel 51 where a mesh part 51a which is so coarse that only toner particles pass through is formed in the lower part, a gas introducing hole 52 which introduces compressed gas (gaseous nitrogen), and a compressed gas supply source. Toner particles pass the alternating electric field due to an electrode 54, and clusters of toner particles are separated to individual toner particles, and they are introduced to a suction tube 1 as toner particle units continuously and automatically. The developer vessel 51 has a capacity to store the quantity of the developer required for one measurement.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention produces an electric field of substantially uniform strength and an air flow of substantially uniform velocity flowing through the electric field in an internal chamber of a housing, and The present invention relates to a toner particle charge distribution measuring device for introducing toner particles into a toner particle and measuring the charge distribution of the toner particles.

(Prior Art) FIG. 1 is a block diagram showing the main parts of this type of device. In the figure, 1 is a suction pipe, which is a glass tube with a narrowed middle part.
Moreover, its inner surface is coated with tin oxide, and the tin oxide is grounded. An annular conductive air filter material 2 is disposed around the opening of the suction pipe 1, allowing air to flow into the suction pipe 1 from the surrounding area. The air filter material 2 is used to form an air layer coaxially surrounding the toner particles (sample) entering the suction pipe 1 in the direction of the arrow. It is a porous member that exhibits resistance and removes dust, etc., and is electrically conductive around the pores. 3 is a nylon filter for introducing the main air flow into the internal chamber 5 of the housing 4, which is then passed through a nylon mesh screen 6, a honeycomb straight air flow former 7. It passes through the nylon filters 8 and 9 and flows downward in FIG. 1 with a substantially flat flow velocity distribution and at substantially the same flow velocity as the air flowing out from the suction pipe 1. Reference numeral 10 denotes a side wall electrode for deflection, which is made of a large number of substantially rectangular tin oxides coated on the glass wall surface of the housing 4. Different voltages are applied to the side wall electrodes 10 so that a uniform electric field is formed within the interior chamber 5 of the housing 4. Reference numeral 11 has an air permeable structure composed of electric wires spaced at approximately equal intervals and nylon wires spaced at approximately equal intervals in a direction perpendicular to the wires.
A grid-shaped bottom electrode is disposed downstream of the filter 12 and forms a smooth potential gradient so as not to distort the particle pattern collected and attached to the filter 12. The resistance to the bottom electrode 11 is formed by coating one edge of the grid with a slurry of colloidal graphite and molybdenum disulfide to create a coated resistor with an end-to-end resistance of, for example, 20 MΩ. This bottom electrode 11 is supported by a glass frit filter 14 attached to a pedestal 13.

In this device, the toner particles are guided through the suction pipe 1 into the internal chamber 5 of the housing 4 by toner particle introducing means, and while descending, the toner particles are transported by electrodes 10 and 11 in a direction perpendicular to the central axis of the suction pipe 1 ( direction of the electric field),
The toner adheres to the filter 12 for detecting toner adhesion. This displacement in the deflection direction is a function of the size and charge of the toner particles.

By the way, as shown in FIG. 2, the means for introducing toner particles into the suction tube 1 in a conventional device of this type is to magnetically attract the developer 20 to a support member 22 attached to a magnetic chuck 21. Approximately 5 mm to 1 Q mm at the edge of suction pipe 1
Air needle 2 is held at a 45° angle.
3, the toner particles are separated from the developer 20 (carrier particles) by blowing air and introduced into the suction pipe 1.

3 and 4 respectively show the support member 22. This is a detailed view showing the ff near needle 23. In FIG. 3, reference numeral 25 is a horseshoe-shaped magnet, and the developer 20 is supported near the tips (poles) of thin wires 26 which are attached to this magnet and are separated by -1.

Further, in FIG. 4, numeral 28 is a Pyrex glass tube provided with a thin nozzle for forming an air jet, and the glass tube 28 is inserted into two stainless steel tubes and fixed with an adhesive 30.

This conventional means for introducing toner particles has the following problems. That is, since the amount of toner that can be held by the magnetic chuck is small, developer must be replenished several times for one measurement of the charge distribution of toner particles. Therefore, measurement is time-consuming. In addition, since the technology for introducing only toner particles into the suction pipe without scattering carrier particles is sophisticated, only an experienced person can operate it.

(Objective of the Invention) The present invention has been made in view of the above points, and its object is to be able to introduce toner particles necessary for -times of charge distribution measurement of toner particles at once, and to An object of the present invention is to provide a toner particle charge distribution measuring device that does not cause scattering and can automate the introduction of toner particles.

(Structure of the Invention) The seventh invention that achieves this object generates an electric field of substantially uniform strength and an air flow of substantially uniform velocity flowing through the electric field in the internal chamber of the housing, and also generates toner particles in the internal chamber. A toner particle charge distribution measuring device that measures the charge distribution of the toner particles by introducing a blow-off device that includes a developer container with a mesh portion formed at the bottom and blows compressed gas into the container; A means for introducing the toner particles into the suction pipe is configured by an electrode that generates an alternating electric field in a flow path of toner particles discharged from the mesh portion to the outside of the developer container and heading toward the suction pipe. It is something to cover.

(Example) Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 5 is a configuration diagram showing the main parts of one embodiment of the present invention.
The same parts as in FIGS. 4 to 4 are given the same reference numerals. In FIG. 5, reference numeral 50 denotes a blow-off device, which includes a developer container 51 in which a mesh portion 51a having a roughness that allows only toner particles to pass through is formed in the lower part, and a compressed gas (for example, nitrogen gas) is introduced into the container 51. It consists of an inlet 52 and a compressed gas supply source (not shown). 53 is a cylindrical tube whose upper part is attached to the developer container 51 and whose lower part is attached to the peripheral part of the suction pipe 1;
The inner wall surface of the cylindrical tube 53 is provided with electrodes 54 made up of at least a pair of opposing conductor plates. This electrode 54
A high-voltage AC voltage is applied from an AC power source (not shown).

Next, the operation of the above embodiment will be explained.

First, by the action of the blow-off device, toner particles are separated from the developer 20 in the developer container 51, and the mesh part 51
It exits the developer container 51 from a point a and starts descending. During this descent, the toner particles pass through an alternating electric field produced by the electrode 54, so that the cluster of toner particles is separated into individual toner particles.

After passing through this electric field, the toner particles are sucked into the suction pipe 1. Therefore, the toner particles in the developer 20 are continuously and automatically introduced into the suction pipe 1 in units of toner particles.

Note that the hole in the mesh portion 51a of the developer container 51 is the main hole 119.
The developer container 51 may have any size as long as it allows the toner particles to pass through without passing through the toner particles, and the capacity of the developer container 51 is such that it can contain the amount of developer required for one measurement. Good to have. Further, the electrode 54 may be formed of a conductive film. Furthermore, it goes without saying that the configuration of the apparatus of the present invention corresponding to that shown in FIG. 1 does not have to be the same as that shown in FIG. 1.

(Effects of the Invention) As described above, according to the present invention, the toner particles necessary for one measurement can be supplied at once, and the measurement does not take much time. In addition, due to the function of the blow-off device and electrodes,
Toner particles can be introduced into the suction port automatically and in units of toner particles. Of course, there is no scattering of carrier particles.

[Brief explanation of drawings]

1 to 4 are configuration diagrams showing a conventional toner particle charge distribution measurement device, and FIG. 1 shows the main configuration of the measurement section,
Figure 2 shows the structure of the toner particle introducing section, Figures 3 and 4
Each figure shows the detailed structure of the support member and air needle in FIG. 2. Further, FIG. 5 is a configuration diagram showing the main parts of an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1...Suction pipe 2...Air filter material 4...Housing 5...Internal chamber 15...Compressed air inlet path 50...Blow-off device 51...Developer container 51a...Mesh Part 52・
...Inlet port 53...Cylindrical tube 54...Electrode plate patent applicant Roku Konishi Photo Industry Co., Ltd. Representative Patent attorney Fuji Ijima Yasuo 2, 3, 2, 4, 7, 5

Claims (1)

[Claims] An electric field of substantially uniform strength and an air flow of substantially uniform velocity flowing through the electric field are generated in the internal chamber of the housing, and toner particles are introduced into the internal chamber and the charge distribution of the toner particles is measured. The charge distribution measuring device includes a blow-off device that includes a developer container with a mesh portion formed at the bottom and blows compressed gas into the container; and a blow-off device that blows compressed gas from the mesh portion to the outside of the developer container and into a suction pipe. An apparatus for measuring charge distribution of toner particles, characterized in that a means for introducing the toner particles into the suction pipe is constituted by an electrode that generates an alternating electric field in a flow path of the toner particles.