JPS6022349Y2 - Diazo copying machine developing device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a developing device for a diazo copying machine.

In a diazo copying machine, the photosensitive paper that has been printed is held under pressure between a developing roller and a coating roller, and the photosensitive paper is conveyed by both rollers, so that the developing solution on the circumferential surface of the developing roller is transferred to the photosensitive paper. It is applied to paper and developed.

FIG. 1 shows a conventional example of a developing device for a diazo copying machine, in which a developer is stored in a developer tank 1.
A portion of the circumferential surface of the application roller 2 is immersed in this developer.

The application roller 2 is designed to be able to rotate in the direction of the arrow, and the excess developer drawn up by this rotational action is
It is squeezed by the developing roller 3 rotating in contact with the application roller 2, and the required amount is supplied and adhered to this peripheral surface.

The developing roller 3 and the pressure roller 4 convey the printed photosensitive paper S in the direction of the arrow while applying pressure thereto. Develop the photosensitive image.

The uppermost pressure roller 5 presses the next pressure roller 4 against the developing roller 3 and this roller 3 against the applicator roller 2 with a predetermined pressure, and presses the next pressure roller 4 against the developing roller 3 with a predetermined pressure. The pressure clamping force between the rollers 2 and 3 and the pressure contact force between the rollers 2 and 3 are determined.

The applicator roller 2 is made of stainless steel, for example, and the developing roller 3, pressure roller 4, pressure roller 5, etc. are made of rubber, stainless steel, and rubber, respectively. ing.

Usually, this type of diazo copying machine is provided with a copying speed adjustment dial that can be operated from outside the machine, and by rotating this dial, the copying speed can be changed.

For example, the rotation speed of each roller in FIG. 1 changes.

The copying speed is changed by, for example, controlling the speed of a DC motor as a drive source using a variable resistance system linked to the dial.

By the way, in the conventional developing device, the pressure applied by the pressure roller 5 is always constant, and the pressure cannot be changed depending on the copying speed.

On the other hand, it is known that the amount of developer supplied to the photosensitive paper, so to speak, the amount of developer attached to the photosensitive paper is proportional to the amount of developer on the developing roller 3.

Furthermore, when the developing speed increases, that is, when the rotational speeds of the application roller 2, the developing roller 3, etc. increase, the amount of developer that adheres to the developing roller also increases.

This is because as the development speed increases, the amount of developer pumped up by the application roller 2 increases.

That is, as shown in FIG. 2, as the development speed increases, the amount of developer attached to the photosensitive paper gradually increases.

Further, the excess developer drawn up by the coating roller 2 is squeezed by the developing roller 3, and the required amount is supplied to the developing roller 3, which is then supplied and coated onto the photosensitive paper. The amount of developer applied, that is, the amount of adhesion, depends on the squeezing force of the developing roller 3.

This squeezing force is determined by the pressurizing force from the pressure roller 5, and as the pressurizing force increases, the squeezing force also increases, and therefore,
The amount of developer that adheres to the photosensitive paper is reduced.

Conversely, as the pressing force decreases, the squeezing force also decreases, and therefore the amount of developer attached increases.

FIG. 3 shows such a relationship.

In view of this, it is possible to make the amount of developer adhering to the photosensitive paper constant by changing the above-mentioned pressure according to the development speed, but in conventional developing devices, the above-mentioned pressure is It is not possible to change the pressure according to the development speed,
Since it is constant, the amount of developer attached to the photosensitive paper will increase as the development speed increases. For example, in a high speed range, a large amount of developer will adhere, and as a result,
There are drawbacks such as so-called poor fading properties, increased curling, and poor tactility.

On the other hand, as shown in FIG. 4, in this type of developing device, blades 6 and 7 are brought into contact with the coating roller 2 and the developing roller 3, respectively, and the blades remove excess developer and develop the required amount. There is one in which a liquid is supplied and applied to photosensitive paper.

Conventionally, in this developing device, the blade pressure applied to each roller is constant regardless of the developing speed.

By the way, as shown in FIG. 5, it is known that as the blade pressure increases, the amount of developer attached gradually decreases.In the conventional developing device, as mentioned above, the blade pressure is constant, so the development speed is As a result, the amount of developer adhering to the photosensitive paper increases.

In particular, in a high speed range, a large amount of developer adheres, and even in a developing device using a blade, similar to the conventional example described above, it may cause poor fading, increased curling, or poor feel. There were some drawbacks, such as:

The purpose of this invention is to reduce or increase the amount of developer supplied from the applicator roller to the developing roller to the photosensitive paper in response to an increase or decrease in the developing speed of the copying machine, thereby preventing the developer from adhering to the photosensitive paper. The objective is to eliminate the above-mentioned conventional drawbacks by always keeping the amount constant.

The present invention will be explained below with reference to illustrated embodiments.

FIG. 6 shows a developing device of a diazo copying machine according to an embodiment of the present invention.

In addition, in the drawings, parts that are distantly related to the same functions as those of the conventional device are denoted by the same reference numerals for convenience in the present invention, and a description of the functions of each member will be omitted here.

In the figure, the pressurizing arm 10 has an arm 10a and an arm 10b, and these arms are substantially integrally constructed.

The pressure arm 10 is pivotally connected to the side plate 12 by a shaft 11, and a pressure roller 5 and a cam follower 13 are rotatably mounted on both ends of the arms 10b and 10a, respectively.

The copy speed adjustment dial (hereinafter referred to as dial) 14 is
It is possible to rotate the copying machine from the outside, and when the dial 14 is turned clockwise as indicated by the arrow, the rotational speed of the DC motor that is the drive source is increased by a variable resistance system, and the rotational speed is accordingly increased. Therefore, the developing speed, that is, the rotational speed of each roller from roller 2 to roller 5 in FIG. 6 increases.

Conversely, when the dial 14 is turned counterclockwise from the maximum clockwise position, the rotational speed of each roller decreases.

That is, the conveyance speed of the photosensitive paper is increased or decreased depending on the direction of rotation of the dial 14.

On the shaft 15 on which the dial 14 is fixedly attached, a pressurizing force adjusting cam 16 is also fixedly attached, and the cam follower 13 is in contact with this cam 16 at the position shown in the figure.

Now, when the dial 14 is turned in the direction of the arrow, the development speed increases as mentioned above, and the pressure adjustment cam 16 rotates in the same direction, pushing up the cam follower 13 and pushing up the pressure arm 10. is rotated counterclockwise around the shaft 11 through a relatively small angle.

Then, the pressing force from the pressure roller 5 to the pressure roller 4 increases, the developer squeezing force of the developing roller 3 to the coating roller 2 increases, and the amount of developer attached to the photosensitive paper S decreases.

Furthermore, when the dial 14 is turned from a certain rotational position in the direction opposite to the direction of the arrow, the developing speed decreases and at the same time the cam follower 13 falls along the cam edge of the cam 16, so the above-mentioned pressing force decreases and the developing roller The squeezing force of the developer applied to the coating roller 2 of No. 3 decreases, and the amount of developer attached to the photosensitive paper S increases.

In this way, since the developer squeezing force changes depending on the development speed, that is, the rotational speed of the application roller 2, the development roller 3, etc., the amount of developer attached to the photosensitive paper can be kept constant regardless of the development speed. can do.

Therefore, it is possible to eliminate the drawbacks of conventional devices, such as poor fading, increased curling, and poor tactility.

Note that the amount of change in the pressing force corresponding to the development speed can be arbitrarily set by changing the cam diagram of the pressing force adjustment cam 16.

FIG. 7 shows a blade-type developing device that can maintain a constant amount of the developer attached to the photosensitive paper as described above.

In the figure, a copying speed adjustment dial 20 can be rotated from outside the machine.

The swing arm 21 is fixedly attached to a shaft 22 located at the swing fulcrum, and the shaft 22 is rotatably supported by a side plate (not shown).

A shaft 23 of the dial 20 and a shaft 24 extending in the direction of extension thereof are connected via a link 25, and a drive gear 26 is mounted on one shaft 24.

The shaft 24 is attached to the swing arm 21 via a member 27 that rotatably supports it.

On the other hand, an adjustment shaft 29 having a blade pressure adjustment gear 28 mounted on the -shaft end is fitted into the shaft 22 of the swing arm 21.
In addition, the other end of the adjustment shaft 29 has a left-hand thread.

Note that the blade pressure adjustment gear 28 meshes with the drive gear 26.

A link rod 32 and a connecting rod 3 are rotatable with respect to a fixed shaft 31.
3 by a rivet pin 34, and a pin 35 is rotatably provided at the end of the connecting rod 33.

This pin 35 has an internal thread, into which the threaded portion of the adjustment shaft 29 is screwed.

The link rod 36 is similarly rotatable about a fixed shaft 37, and is connected to a connecting rod 39 via a stud pin 38, and this connecting rod 39 is connected to the swing arm 21 via a pin 41. ing.

The swinging arm 21 has a spring 42 centered around the fulcrum shaft 22.
The elastic force gives it a tendency to rotate counterclockwise, and this rotation due to this habit is prevented by the stopper pin 43.

In addition, each of the link rods 32 and 36 has a blade 44.
．． 45 is fixedly installed.

A clutch lever 47 pivotally mounted on a shaft 46 is connected to a solenoid 49 via a spring 48.
7 is formed with a pair of locking claws 47a and 47b.

One of the locking claws 47a is engaged with the edge of the locking groove 51a of the sleeve clutch 51.

An operating cam 53 is provided on a shaft 52 located at the center of the sleeve clutch 51, and the rotational action of this cam 53 pushes and moves a cam follower pin 56 for linking link rods 54 and 55. It is now possible to

A pin 55a is installed at the end of the link rod 55,
This pin 55a is inserted into the long hole 57 of the side plate 57 as shown in FIG.
It is fitted in a.

In FIG. 7, the link rod 54 is pivotally connected to a shaft 58, and is normally held in the position shown by a spring 59 and a stopper pin 60.

Now, in FIG. 7, when the main switch of the copying machine is turned on, the solenoid 49 is energized, and the clutch lever 47 is accordingly rotated counterclockwise around the shaft 46. move.

Then, one of the locking pawls 47a of the clutch lever 47 separates from the locking groove 51a of the sleeve clutch 51, and at the same time, the operating cam 53 starts rotating in the direction of the arrow.

While the operating cam 53 rotates, the cam follower 56 is pushed and moved according to the cam shape of the cam 53, and accordingly, the link rod 54 rotates clockwise around the shaft 58, and the other link rod 55 rises.

When the link rod 55 rises, the pin 55a moves toward the swing arm 2.
1, and the arm 21 is rotated clockwise about the shaft 22.

At this time, the shaft 22 also rotates integrally with the arm 21, and the shaft 24 and the adjustment shaft 29 also rotate integrally with the arm 21.

When the link rod 55 reaches its highest point, as shown in FIG.
The operating cam 53 rotates exactly 172 turns from the position shown in FIG. 7, and in this state, the other locking pawl 47b of the clutch lever 47 enters the locking 151a of the sleeve clutch 51, thereby disabling the clutch mechanism. Then, the operating cam 53 is 1n.
It is designed to stop in the rotated state, that is, in the position shown in FIG.

With the operating cam 53 rotated 172 times, the swing arm 21
rotates to the position shown in Fig. 8, and during this rotation, the connecting rod 53
The link rod 32 rotates clockwise around the shaft 31 via the link rod 31, and the blade 44 comes into contact with the circumferential surface of the application roller 2, as shown in FIG.

On the other hand, due to the above-mentioned rotational movement of the swinging arm 21, the connecting rod 5
9, the link rod 36 rotates counterclockwise around the shaft 37 to the position shown in FIGS. 7 to 8, and the blade 45
comes into contact with the developing roller 3.

Note that when the swing arm 21 rotates clockwise together with and around the shaft 22, a pin 35 to which the adjustment shaft 29 is screwed is provided so as to be freely rotatable with respect to the connecting rod 33. Therefore, the rotational movement of the arm 21 is not obstructed.

In this way, after the main switch is turned on, both blades 44 and 45 come into contact with the application roller 2 and the developing roller 3, respectively. In this state, the excess developer is removed by the blades and the required amount is An amount of developer solution is applied to the photosensitive paper.

Next, in FIG. 8, the copying speed adjustment dial 20 is
For example, when viewed from the direction of arrow a and rotated clockwise,
Due to the variable resistance method, the rotational speed of the DC motor serving as the drive source is increased, and the developing speed, that is, the rotational speed of the coating roller 2, the developing roller 3, etc., increases accordingly.

On the other hand, by the above rotation operation of the dial 20, the link 2
5, the shaft 24 rotates, and the drive gear 26 rotates clockwise.

Then, the blade pressure adjustment gear 28 meshing with the gear 26
For example, the rotation speed is increased and the adjustment shaft 29 is also rotated in the counterclockwise direction.

Along with this, since the threaded portion of the adjustment shaft 29 is a left-handed thread, the pin 35 descends along the elongated hole 21b, and the link rod 32 moves slightly around the shaft 31 via the connecting rod 33. The applicator roller 2 of the blade 44 rotates clockwise.
Increase the contact force against the

That is, as shown in FIG. 5, since the blade pressure increases, the amount of developer adhering to the photosensitive paper can be reduced.

Conversely, if the dial 20 is now rotated counterclockwise, the developing speed is reduced and the blade pressure is weakened, making it possible to increase the amount of developer that adheres to the photosensitive paper.

In this way, even if the development speed changes, the blade pressure changes accordingly, so that the amount of developer adhering to the photosensitive paper can be kept constant regardless of the development speed.

In addition, adjustment of the blade pressure by the upper blade 45 is also possible.
This can be done by a similar mechanism.

In addition, the adjustment range of the blade pressure is determined by the blade adjustment gear 28.
It can be made variable by arbitrarily selecting and setting the number of teeth.

Note that when the main switch of the copying machine is turned off, the excitation state of the solenoid 49 in FIG. 8 is immediately released.
As a result, the clutch lever 47 is rotated clockwise by the elastic force of the spring 61, releasing the sleeve clutch 51 and rotating the actuating cam 53 to the position shown in FIG.

During this time, the link rod 54 is moved to the shaft 5 by the elasticity of the spring 59.
8 in a counterclockwise direction until the stopper pin 60 is engaged.

In this state, the other link rod 55 also assumes the position shown in FIG. 7, and furthermore, the swinging arm 21 also rotates back to the position shown in the same figure due to the elasticity of the spring 42, and both waist blades 44 and 45 are moved to the application rollers. 2. Separate from the developing roller 3.

In this copying machine, when the developing speed changes, the current of the drive motor changes. Taking advantage of this fact, as shown in FIG. The blade pressure by the blade 64 equipped with the permanent magnet 64a may be adjusted and controlled.

By adjusting the amount of developer supplied as described above, even if the development speed changes, the amount of developer attached to the photosensitive paper can always be kept constant, eliminating the conventional drawbacks such as poor fading. be able to.

According to the present invention, depending on the increase or decrease in development speed,
The amount of developer supplied from the application roller to the photosensitive paper via the developing roller can be decreased or increased, respectively, and the amount of developer applied to the photosensitive paper can always be kept constant.
It is possible to prevent the occurrence of poor fading properties and increase in curling, and to obtain copies of good quality with excellent tactility.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the main parts of the developing device of a conventional diazo copying machine, and Fig. 2 is a graph showing the correlation between the developing speed in the developing device and the amount of developer attached to the photosensitive paper. ,
Figure 3 is a graph showing the correlation between the pressure applied by the developing roller to the applicator roller in the developing device and the amount of developer attached to the photosensitive paper. Figure 4 shows an example of the developing device using a blade, showing only the main parts. 5 is a graph showing the correlation between the blade pressure by the blade and the amount of developer attached to the photosensitive paper. FIG. 6 is a front view of the developing device of the present invention-example. The figure is a front view of a developing device according to another embodiment of the present invention, FIG. 8 is an operational view from FIG. 7 showing the state in which the blades of the same developing device are in contact with the application roller and the developing roller, respectively, and FIG. 9 1 is a front view of a link mechanism for rotating a swing arm, which is provided in the developing device, and FIG. 10 is a diagram showing another example of the blade pressure adjustment mechanism using the blade. 1...Developer tank, 2...Applying roller 3
...Developing roller, 4...Pressure roller,
10... Pressure arm, 16... Pressure adjustment cam, 20... Copying speed adjustment dial, 26
... Drive gear, 28 ... Blade pressure adjustment gear, 29 ... Adjustment shaft, 32 ... Link rod, 33 ... Connection rod , 44, 45...
··blade.

Claims (1)

[Scope of utility model registration request] A coating roller that is partially immersed in a developer tank and draws up the developer as it rotates, a developing roller that rotates in contact with the coating roller and causes the developer to adhere to its peripheral surface, and a photosensitive paper. The developing roller that supplies and coats the adhered developer contacts the pressure roller that presses and holds the photosensitive paper and transports the photosensitive paper, and the coating roller and the developing roller that contact at least one of the rollers to remove excess developer. In order to keep the removal blade and the amount of developer attached to the photosensitive paper constant, the blade pressure by the blade or the pressing force by the pressure roller is increased or decreased in accordance with the increase or decrease in the conveyance speed of the photosensitive paper. 1. A developing device for a diazo copying machine, comprising: an adjusting means.