JPH08131870A - Toner pulverizing device - Google Patents

Abstract

PURPOSE: To provide a toner pulverizing device capable of making a toner pulverizing capacity much higher than theretofore. CONSTITUTION: This toner pulverizing device has a pulverizing chamber 107 which pulverizes toners to be pulverized, a hopper 106 which is disposed substantially above this pulverizing chamber 107 and supplies the toners to be pulverized into the pulverizing chamber 107 and a dispersion plate 1 which is disposed in the upper part of this hopper 106 and executes, dispersedly in time, the supply of the coarse powder returned at one time to the hopper 106 from a post-stage classifying machine 105 for dividing at least the pulverized toners to be pulverized to the coarse powder and fine powder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner crushing device for crushing a toner raw material into a toner having a desired particle size as a toner used in an image forming apparatus or the like.

[0002]

2. Description of the Related Art Toner is generally known as an image forming powder material used in an image forming apparatus such as a copying machine.

There is a toner crushing device as a device for crushing the toner raw material to a predetermined particle size or less for producing this toner.

As a conventional toner fine pulverization equipment, as shown in FIG. 4, there are two series of pre-stage classifiers 102, 1 in addition to a collision type air flow pulverizer 101 as an example of a toner pulverizer.
03 and a rear stage classifier 1 equipped with a double damper section 104
It is common to use a system combining 05.

The structure of a conventional toner crushing device will be described below with reference to FIG. 4, which is a block diagram of the toner fine crushing equipment, and the operation of each part will be described.

In the figure, a collision type airflow crusher 101
Has a hopper 106 at the top and a crushing chamber 1 at the bottom.
It is configured to include 07.

The hopper 106 is in the form of a bowl for supplying a toner raw material to be crushed (hereinafter referred to as a crushed toner) to the crushing chamber 107. Further, the crushing chamber 107 is provided internally with a collision plate (not shown) for crushing the toner to be crushed supplied from the hopper 106 into finer particles. This grinding chamber 107
Is connected to the inlet side of the former stage classifiers 102 and 103 by a pipe 108.

In the crushing chamber 107, the crushed toner is crushed into finer particles by being conveyed at high speed by the jet air of crushing air blown from a nozzle (not shown) and hitting the collision plate. Usually, the grinding air pressure is set to 6.0 kg / cm ² . The toner particles pulverized in this way are conveyed to the former stage classifiers 102 and 103 through the pipe 108.

The former stage classifiers 102 and 103 are provided in the crushing chamber 1
The toner raw material crushed in 07 is separated into a coarse powder and a fine powder according to the particle size, and the coarse powder is returned to the hopper 106 again, and is connected to the pipe so that the recycle pulverization can be performed. In the former stage classifiers 102 and 103, the latter stage classifier 105
Since it does not require the classification accuracy to the extent required by, the double damper part described later is not provided.

The recycle pipe 111 is a return pipe connected to the pre-stage classifier 102 for the recycle pulverization, and the recycle pipe 112 is a return pipe connected to the pre-stage classifier 103 for the recycle pulverization. .

The rear-stage classifiers 105 are each of the front-stage classifiers 10
The fine powders classified by 2, 103 are collected and subjected to classification treatment again, and finally the central particle diameter set corresponding to the desired particle diameter (the central particle diameter means the central value of the particle diameter distribution). The toner particles satisfying the condition (4) are selected as crushed products. Therefore, the latter-stage classifier 105 is required to have high classification accuracy. Double damper recycling pipe 113
It is a return pipe for returning the toner particles selected as coarse powder by the latter-stage classifier 105 to the hopper 106 again.

The double damper section 104 is a rear stage classifier 1.
This is for maintaining the classification accuracy of 05. That is, the double damper unit 104 has two dampers (not shown) inside in order to maintain the value of the negative pressure in the latter stage classification 105 required to maintain the above classification accuracy at a predetermined value or less.
And the opening and closing operations thereof are staggered in time so that they are not simultaneously opened.
Therefore, of the two dampers in the double damper section 104, the damper closer to the hopper 106 is 1 in 20 seconds.
The coarse powder is returned to the hopper 106 each time the periodic opening and closing is repeated.

In this way, the recycled coarse powder is supplied again from the hopper 106 to the crushing chamber 107 and crushed into finer particles.

[0014]

However, in the structure of the conventional toner crushing device as described above, the rear stage classifier 105 classifies the double damper portion 104 while the damper closer to the hopper 106 is closed. The disadvantage is that the coarse powder temporarily stored inside the double tamper unit 104 exceeds a predetermined amount and is supplied to the crushing chamber 107 at one time each time the damper is periodically opened. there were. Therefore, there is a problem that the toner crushing ability of the toner crushing device is lowered.

An object of the present invention is to provide a toner crushing device capable of further improving the toner crushing capacity as compared with the conventional toner crushing device in consideration of the above problems of the conventional toner crushing device.

[0016]

According to a first aspect of the present invention, there is provided a crushing unit for crushing toner to be crushed, and the crushing unit is provided substantially above the crushing unit and supplies the crushable toner to the crushing unit. It is a toner crushing device provided with a hopper and a plate-like dispersion member for dispersing and supplying the crushed toner to the crushing means.

According to a second aspect of the present invention, the dispersing means has a plurality of holes, and the plate-shaped surface portion in which the holes are formed is 40 ° to 6 ° with reference to the horizontal plane of the upper edge of the hopper.
The toner crushing device is positioned at an inclination angle of 0 °.

[0018]

According to the present invention, the crushing means crushes the toner to be crushed, and the hopper is provided substantially above the crushing means. The crushing means is supplied with the toner to be crushed. The pulverized toner is supplied to the pulverizing means in a dispersed manner.

[0019]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a toner finely pulverizing equipment using a toner pulverizing apparatus according to an embodiment of the present invention. The configuration of the present embodiment will be described with reference to FIG. 2, FIG. 2 and FIG.

In FIG. 1, the same components as those used in FIG. 4 are designated by the same reference numerals, and their description will be omitted.

In FIG. 1, the dispersion plate 1 is a hopper 106.
It is a stainless steel plate having a plurality of holes, which is arranged so as to project obliquely downward in the inside of the container, and corresponds to the dispersion means of the present invention. The crushing means of the present invention corresponds to the crushing chamber 107 of FIG.

FIG. 2 is a schematic plan view of the hopper 106 to which the dispersion plate 1 is attached when the hopper 106 to which the dispersion plate 1 is attached is looked down from the double damper recycling pipe 113 side.

As shown in FIG. 2, at the upper part of the hopper 106, 800 mm × 1 for collecting the toner particles returned as coarse powder from the recycle pipes 111, 112 and the double damper recycle pipe 113.
200 rectangular openings 2 are provided. At the end edge of the opening 2, horizontally 50 m to the outside of the opening 2.
A flange portion 3 protruding to a length of m is provided on the entire circumference. Three dispersion plate fixing holes 4 to which the dispersion plate 1 can be attached are formed in a part of the flange portion 3 (downward in the drawing).

The dispersion plate 1 is fixed to a part of the flange portion 3 by using the dispersion plate fixing hole 4. FIG.
(A), (b), (c) is a figure showing the shape of the dispersion plate 1, the same figure (a) is the top view at the time of seeing the dispersion plate 1 from a back surface side, the same figure (b). Is a side view of the dispersion plate 1, and FIG. 6C is a view as seen from the arrow A in FIG.

When viewed from the side, the dispersion plate 1 is an elongated plate bent in a substantially "V" shape, and the bending angle of the bending portion 34 is θ + 90 ° (where the mounting angle θ is
θ> 0 °) (see FIG. 3 (b)). Incidentally, FIG. 3 (a)
In (c), the case of θ = 45 ° is shown.
The description will focus on the case of θ = 45 °.

The long side of the "he" character of the dispersion plate 1 is 3
It has a rectangular flat plate shape of 60 mm × 800 mm, and L-shaped bent portions 33 for preventing deformation are provided at both end portions (upper and lower end portions of FIG. 3A) of the flat plate shape to prevent deformation. Only the length projects toward the back surface (Fig. 3 (a),
(B)). Also, the inner diameter is φ
A total of 44 toner drop through holes 31 of 40 mm are provided (see FIG. 3A).

These holes are arranged in consideration of the positional relationship with a return pipe opening 113a described later when the dispersion plate 1 is attached. When the dispersion plate 1 is attached to the hopper 106, a portion corresponding to a position where the return pipe opening 113a is located almost right above, that is, 140 mm away from the bent portion 34 and a central portion P having a width of 360 mm, Only one through hole 31 for dropping toner is provided. And 70m to the left and right in the figure of the central portion P
3 to 5 toner drop through holes 3 per row at m row intervals
1 are provided at a pitch of 35 mm (see FIG. 3A).

On the other hand, the short side portion of the "he" shape of the dispersion plate 1 has a rectangular flat plate shape of 360 mm × 150 mm,
One rectangular through hole 32 of 150 mm × 50 mm is provided at the substantially central portion (see FIG. 3C). Furthermore,
Three B holes 35 for fixing the dispersion plate having a diameter of 15 mm are formed at a pitch of 120 mm at a position 25 mm away from the bent portion 34 on the short side. The positions of these three B holes 35 for fixing the dispersion plate correspond to the A holes 4 for fixing the dispersion plate described in FIG.

Referring again to FIG. 2, the fixed dispersion plate 1 and the double damper recycle pipe 113 are shown in FIG.
Return pipe opening 113a facing the hopper 106 side of the
(Indicated by a chain double-dashed line in the figure). Here, the outer diameter dimension of the return pipe opening 113a is about φ140 mm, and the return pipe opening 113a
The reference character a is fixed to a portion where a through hole 31 for dropping toner is formed and which is raised from the flat plate-shaped portion of the dispersion plate 1 by a predetermined dimension (to the front side in the drawing).

As is clear from the figure, the positions of the center of the return pipe opening 113a and the above-mentioned central portion P are as follows.
It almost agrees. In order to avoid complication of the drawing, the display of the toner dropping through hole 31 on the dispersion plate 1 is omitted. In addition, in FIG. 2, the long side portion of the “he” shape of the dispersion plate 1 is below the plane of the flange 3 (inward direction in the figure).
Shows a state in which it is attached at an angle of θ = 45 °. This state is the same as the attached state of the dispersion plate 1 shown in FIG. Further, the return pipe openings 111a, 1 facing the hopper 106 side of the recycle pipes 111, 112.
12a (indicated by a chain double-dashed line in the figure) is in the vicinity of both end portions of the upper part of the dispersion plate 1 in the figure as a planar positional relationship with the dispersion plate 1, and an area portion of the hollow half thereof is Dispersion plate 1
It overlaps with the plane part of. The return pipe openings 111a and 112a are provided with the toner drop through holes 3.
It is fixed to a portion that is raised by a predetermined dimension (on the front side in the drawing) from the flat plate-shaped portion on which 1 is formed.

The operation of the present embodiment in the case of θ = 45 ° in the above configuration will be described with reference to FIG. 1, and at the same time, an experimental example in the case of changing the mounting angle θ will be described using Table 1. .

In FIG. 1, the pulverized toner is conveyed to the two-stage pre-stage classifiers 102 and 103 and classified, and the coarse powder passes through the recycle pipes 111 and 112 and the return pipe openings 111a and 112a. Are substantially continuously returned into the opening 2 of the hopper 106.

On the other hand, for the fine powders classified by the former classifiers 102 and 103, the upper classifier 10 on the further downstream side is used.
It is transported to No. 5 and classified again. The toner particles selected as fine powder by this classification process are sent to the final step as pulverized products. However, the toner particles selected as coarse powder are stored in the double damper unit 104, and
Every time the damper is opened at a cycle of once every 0 seconds, a large amount of the liquid drops through the double damper recycle pipe 113 to the central portion P (see FIG. 2) above the dispersion plate 1 and its peripheral portion at one time. Come on.

The toner particles falling around the central portion P in this way are dispersed by the impact of falling and the own weight.
Is gradually moved obliquely downward on the surface of the dispersion plate 1 along the inclination of. In this way, a large amount of toner particles that have fallen at one time move once on the surface of the dispersion plate 1 and, before the new toner particles fall again in the next cycle, the toner drops. The powder is divided into appropriate amounts by the through holes 31 and dispersed in time, and falls into the crushing chamber 107.

By providing the dispersion plate 1 in this manner, it is possible to prevent the recycled coarse powder from returning to the crushing chamber 107 in excess of a predetermined amount at a time.
The crushing capability of the collision type airflow crusher 101 is improved, and the classification accuracy of the classifier does not decrease. Therefore, the latter stage classifier 1
The amount of toner particles selected as fine powder by 05 per unit time, that is, the processing amount per time is also increased.

Next, Table 1 will be used to explain experimental examples in the case where the mounting angle θ of the dispersion plate 1 is changed to other values including the above-mentioned case of θ = 45 °.

Table 1 shows the median particle diameter of the toner particles selected as fine powder by the latter-stage classifier 105 of 9.3 to 9.5 μm.
The relationship between the mounting angle θ of the dispersion plate 1 and the amount of processing per hour when m is set is shown.

However, the crushing air pressures are all the same,
It was set to 6.0 (kg / cm ² ).

..

[Table 1]

Experiments other than those shown in Table 1 were conducted under the following conditions.

That is, when the attachment angle θ is smaller than 40 °, coarse powder remains on the dispersion plate 1 and there is no effect. If the mounting angle θ is larger than 60 °,
The throughput per hour did not increase. Dispersion plate 1
If is not installed, the throughput per hour is 11
It was 0 (kg / hr). This condition corresponds to the conventional case.

As is clear from the above experimental results, when the mounting angle θ of the dispersion plate 1 satisfies the condition of 40 ° ≦ θ ≦ 60 °, the time It can be seen that the effect increases as the amount of processing increases and θ increases.

In the above embodiment, the case where the dispersion plate 1 has the toner dropping through holes 31 formed in its surface has been described, but the present invention is not limited to this, and the toner dropping through holes are provided, for example. It may be a non-plate member.

Further, in the above embodiment, the case where the toner dropping through holes 31 are round holes and the arrangement thereof is as described with reference to FIG. 3 has been described, but the present invention is not limited to this and, for example, The shape of the holes may be a slit shape, a square shape, or the like, or the number of kinds of hole shapes may be not only one but also a plurality of kinds, and the arrangement of the holes may be the opening of the double damper recycling pipe. Of course, a more effective arrangement may be adopted in consideration of the shape, arrangement, and the like.

Further, in the above-mentioned embodiment, the case where the toner particles as the coarse powder is separated from the classifier at a time interval and a large amount is dropped into the hopper each time is explained. Not limited to this, for example, a configuration may be adopted in which toner particles serving as a raw material are temporally spaced from the toner supply device, and a large amount of toner particles are dropped into the hopper each time.

[0047]

As is apparent from the above description, the present invention has an advantage that the toner pulverizing ability can be further improved as compared with the conventional one.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a toner finely pulverizing equipment using a toner pulverizing apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic plan view of a hopper to which a dispersion plate is attached according to this embodiment.

FIG. 3 (a); a plan view of the dispersion plate of the present embodiment as viewed from the back side thereof. FIG. 3 (b); a side view of the dispersion plate of the same embodiment FIG. 3 (c); View of arrow A of the dispersion plate

FIG. 4 is a block diagram of a toner fine pulverization facility using a conventional toner pulverizer.

[Explanation of symbols]

 1 Dispersion plate 2 Opening part 3 Flange part 4 Dispersion plate fixing hole 31 Toner drop through hole 101 Collision type airflow crusher 102, 103 Pre-stage classifier 104 Double damper part 105 Rear stage classifier 106 Hopper 107 Grinding chamber 113 Double damper recycling Piping

Claims (2)

[Claims] 1. A crushing unit for crushing toner to be crushed, a hopper provided substantially above the crushing unit, for supplying the toner to be crushed to the crushing unit, and the toner to be crushed to the crushing unit. And a plate-shaped dispersion member for dispersing and supplying the toner. 2. The dispersing means has a plurality of holes, and the plate-shaped surface portion in which the holes are formed is positioned at an inclination angle of 40 ° to 60 ° with reference to the horizontal plane of the upper end edge of the hopper. The toner crushing device according to claim 1, wherein