JPH04110168A - Image forming apparatus - Google Patents

Abstract

PURPOSE:To record additional information always with a constant image density regardless of the type of paper by a method wherein a conduction time to a thermal head is controlled in accordance with the type of paper when the additional information is recorded. CONSTITUTION:Thermal transfer times suitable for every type of paper are prestored in a control ROM 102. The thermal transfer times stored in the control ROM 102 are so set that a longer thermal transfer time is assigned to paper having lower transfer properties. Various types of copying paper are ranked into several levels in accordance with their thermal transfer properties, and these data are manually inputted from an input key Cl. The aforesaid data are previously empirically found. With the input of the type of paper from the input key Cl, a CPU 100 makes an additional information recording means T record additional information on the paper by selecting an optimum thermal transfer time stored in the control ROM 102 in accordance with the inputted data of the type of paper.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an image forming apparatus such as an electrostatic copying machine or a laser beam printer, and more particularly, to an image forming apparatus such as an electrostatic copying machine or a laser beam printer. The present invention relates to an image forming apparatus equipped with a recording means.

<Prior art and problems to be solved by the invention> Conventionally, in addition to the image forming function of developing an electrostatic latent image formed on the surface of a photoreceptor into a toner image and then transferring it to paper, a thermal head and An image forming apparatus has been proposed that has an additional information recording function that records additional information such as page number and date on the paper using a thermal transfer ribbon (for example, Japanese Patent Application Laid-Open No.
(See Publication No. 977459).

The paper used in image forming apparatuses is not always constant, and in addition to copy paper specified by the manufacturer, papers with poor surface smoothness, such as rough paper, recycled paper, and business paper, are often used.

However, paper with poor surface smoothness has poor thermal transfer efficiency by additional information recording means using a thermal head and a thermal transfer ribbon. For this reason, if an image is recorded using the same thermal transfer time as the copy paper specified by the manufacturer, the density of the recorded image may be insufficient, making it difficult to read.

The present invention has been made in view of the above circumstances, and
It is an object of the present invention to provide an image forming apparatus that can always record additional information at a constant image density regardless of the type of paper.

<Means for Solving the Problems> In order to solve the above problems, an image forming apparatus of the present invention has the following features:
A manual means for inputting the type of paper, a storage means for storing a thermal transfer time suitable for the paper type, and a manual means for inputting a paper type, a storage means for storing a thermal transfer time suitable for the paper type, and a paper input means for inputting the paper type at the thermal transfer time stored in the storage means according to the paper type input to the manual means. The apparatus is characterized by comprising a control means for recording additional information on the apparatus.

Effect> In the image forming apparatus of the present invention having the above configuration,
When the type of paper is input to the input means, the control means records additional information on the paper at the thermal transfer time stored in the storage means in accordance with the type of paper input to the input means.

<Example> An image forming apparatus of the present invention will be described below with reference to drawings showing an electrostatic copying machine as an example.

As shown in FIG. 8, the electrostatic copying machine of this embodiment includes an optical system 11, an image processing section 12, a fixing means, and 13,
Paper transport section 14, additional information recording means T, and perforation section P
It is equipped with

The optical system 11 forms an image of the original placed on the original placing plate 10 on the surface of the photoreceptor 12a of the image processing section 12, and forms an electrostatic latent image corresponding to the original image on the photoreceptor 12a. to form.

The image processing section 12 visualizes the electrostatic latent image into a toner image, and transfers this toner image onto the surface of the paper.

The fixing unit 13 heats the toner image transferred to the surface of the paper,
Apply pressure to fix it on the paper surface.

The paper transport unit 14 sequentially transports the paper fed from the manual paper feed unit 1.5a or the paper feed cassettes 15b and 15c through the image processing unit 12, the fixing unit 13, the additional information recording unit T, and the perforation unit P. After passing through the discharge roller 14
a, 14a to discharge onto the discharge tray 16.

As shown in FIGS. 4 and 5, the perforation section P is disposed between the additional information recording means T and the ejection rollers 14a, 14a, and the perforation section P is arranged between the additional information recording means T and the ejection rollers 14a, 14a, and is used to punch the trailing edge of the paper that has passed through the additional information recording means T. The punch blade P1 is pushed into the side by the cam P2, and a plurality of punch holes for binding are punched in the paper.

This perforation part P is arranged on a unit U whose portions other than the cam P2 rotate outward of the casing 1 about an axis U1 at the lower end, as shown in FIG. When unit U is rotated outward of casing 1, punch blade P1
Since the engagement between the punch blade P1 and the cam P2 is released, and the punch blade P1 becomes free, it becomes easy to clear a jam in a state where the bunch blade P1 is pushed into the paper. Also, unit U
When the additional information recording means T is rotated outward of the casing 1, the additional information recording means T located deep therein is exposed, so that maintenance of the additional information recording means T becomes easier.

As shown in FIG. 7, the additional information recording means T is detachably attached to the casing 2, and
A ribbon cassette 3 containing a band-shaped thermal transfer ribbon R therein, a support member 4 rotatably attached to the casing 2, and a thermal head 5 supported by the support member 4.
and a thermal head moving means 9 for pushing out the thermal head 5 in the direction of the platen roller 7 disposed oppositely across the paper path.

The casing 2 includes a box 21 with an open top and side plates 22a fixed to both ends of the box 21.

22b. The side plates 22a and 22b have a substantially triangular shape, and are attached directly or indirectly to the copying machine main body 1 by a support shaft 24 at the lower end. Casing 2
is rotatable about the support shaft 24 between a set position shown by a two-dot chain line in FIG. 6 and an open position from which the ribbon cassette 3 can be taken out, shown by a solid line in the same figure.

The ribbon cassette 3 consists of a body 31, a feed-out reel 32 rotatably attached to the body 31, around which the thermal transfer ribbon R is wound, and a take-up reel 33. Thermal transfer ribbon R
is wound up by the take-up reel 33. The body 31 has an opening 31a between both reels 3233, and the bottom plate 21 of the box body 21 of the casing 2. a is the opening 31
It has an opening 23 that coincides with a. Thermal head 5
As shown in FIG. 4, the thermal transfer ribbon R can be brought into contact with the paper on the platen roller 7 by protruding downward from the casing 2 through the opening 31a and the opening 23.

Inside the box 21 of the casing 2, the ribbon cassette 3, a driving means 6 for driving the take-up reel 33 of the ribbon cassette 3 to wind up the thermal transfer ribbon R, and a drive means 6 for winding the thermal transfer ribbon R, and a drive means 6 for driving the take-up reel 33 of the ribbon cassette 3 to wind up the thermal transfer ribbon R, and a drive means 6 for winding the thermal transfer ribbon R, and a drive means 6 for driving the take-up reel 33 of the ribbon cassette 3 to wind up the thermal transfer ribbon R, and For installation, a locking member 8 is provided to maintain the state.

The driving means 6 includes a motor 61 and a torque limiter mechanism 62 that transmits the driving force of the motor 61 to the take-up reel 33.
It has When the ribbon cassette 3 is attached to the casing 2 , a connecting shaft (not shown) at the end of the torque limiter mechanism 62 is engaged with the take-up reel 33 .

The locking member 8 consists of a shaft 81 and an L-shaped member 82 that is rotatable about the shaft 81.
The end portion 82a of the ribbon cassette 3 is brought into contact with one side 31a of the body 31 of the ribbon cassette 3 to maintain the ribbon cassette 3 in a predetermined position and prevent it from falling off.

The thermal head 5 is equipped with a plurality of minute resistors, and generates heat by energizing the resistors corresponding to the pattern of additional information to be recorded, melts the thermal transfer ribbon R, and thermally transfers the information to the paper. Record additional information on paper. Further, the thermal head 5 has a built-in thermistor S as a temperature sensor for measuring the temperature of the thermal head 5.

The support member 4 includes a support shaft 41 that is rotatably attached to either end or side plates 22a and 22b, and a plate 42 that is fixed to the lower end or the center of the support shaft 41 and has a thermal head 5 attached to the upper part. It is made up of. This support member 4 has two positions: a recording position (see FIG. 4) where the thermal head 5 is pressed against the thermal transfer ribbon R, and a retraction position (sixth position) where the thermal head 5 is retracted so that the ribbon cassette 3 can be taken out of the casing 1. (see Fig. 7 and Fig. 7).

Further, the support member 4 is moved by the thermal head moving means 9 between the recording position, the retracted position, and a release position located between the two positions (see FIG. 5). The release position is such that when the mode in which additional recording is not performed is selected, the thermal transfer ribbon R is evacuated from the paper path, and the thermal transfer ribbon R accidentally comes into contact with the paper heated by the fixing means 13. is set to prevent it from being contaminated.

The thermal head moving means 9 includes a shaft 91 and a biasing roller 92.
, a bias spring 93, leaf springs 94, 95, and a tension spring 96.

Both ends of the shaft 91 are directly or indirectly supported by the casing 1. The biasing roller 92 has a shaft 91 extending through an elongated hole 92a, and the biasing spring 93 is disposed within the elongated hole 92a.

Due to the action of the biasing spring 93, the biasing roller 92 is biased and rotated with respect to the rotation of the shaft 91.

The leaf spring 94 is attached to one end 94a of the support shaft 41, and the other end 94b extends in the radial direction of the support shaft 4 to abut against the bottom plate 21a of the casing 2 and press the casing 2. Due to the reaction force against this pressing, the plate spring 94 rotationally biases the shaft 41 so that the thermal head 5 can smoothly move from the recording position to the release position.

The plate spring 95 is attached at one end 95 a to the support shaft 41 , and the other end 95 b extends in the radial direction of the support shaft 41 and can be pressed against the biasing roller 92 .

The tension spring 96 is disposed between the plate 42 and the casing 13a of the fixing means 13, and pulls the plate 42 in a direction approaching the casing 13a.

When no additional recording is performed, the biasing spring 93 is located on the upper right side of the shaft 91 as shown in FIG. 5, and no pressing force is generated between the biasing roller 92 and the leaf spring 95. . Therefore, the support member 4 is urged to rotate clockwise by the tensile force of the tension spring 96 and the reaction force of the leaf spring 94, and the thermal head 5 is located at the release position.

On the other hand, when the mode for performing additional recording on paper is selected, by rotating the shaft 91 by half a turn, the biasing spring 93 is placed at the lower left of the shaft 91, as shown in FIG. As a result, the shaft 41 is rotated counterclockwise in FIG. 4 against the reaction force of the pressing of the leaf spring 95 or the biasing roller 92 against the bottom plate 21a, mainly by the leaf spring 94. From the plate 42 fixed to the shaft 41
rotates counterclockwise, and the thermal head 5 is moved to the recording position. Then, when the paper is discharged from the fixing means 13, the limit switch 13b at the exit of the paper or the fixing means 13 is turned over. This limit switch 13
Based on the signal from b, the ejection rollers 14a, 14a and the platen roller 7 slow down the conveyance speed of the paper to a speed at which the additional information recording means T can record.
In this state, additional information is recorded on the paper by the additional information recording means T.

Further, when the casing 2 is rotated from the set position to the open position, the support member 4 is urged to rotate clockwise by the tensile force of the tension spring 96, and the thermal head 5 moves to the retracted position. Therefore, maintenance of the additional information recording means T, such as removing the ribbon cassette 3, can be performed easily.

FIG. 1 shows the electrical configuration of the electrostatic copying machine described above.

As shown in the figure, the CPU 100 as a control means includes:
The operation panel C via the human output interface 101
1 main motor M1, step motor M2, thermal head 5, and thermistor 81. The motor 61 of 1 drive device 6 is connected to the clutch for raising and lowering the head.

The main motor M1 includes an image processing section 12, a fixing means 13,
Drives the paper transport section 14 and the like.

The step motor M2 drives the discharge rollers 14a, 14a and the platen roller 7 separately from the above-mentioned parts.

That is, when recording additional information, the step motor M2 can slow down the paper conveyance speed by the ejection rollers 14a, 14a and the platen roller 7 to the extent that the additional information recording means T can perform recording, as described above. Further, the step motor M2 can stop the rotation of the discharge rollers 14a and the platen roller 7 while the rear end of the sheet faces the punch blade P1 when punching holes are formed by the punching section P. .

The head lifting/lowering clutch connects the shaft 91 of the thermal head moving means 9 described above to a power transmission mechanism from the main motor M1, and rotates the shaft 91 to lift/lower the thermal head 5. be.

The operation panel C has operation keys (
(not shown), and a display C2 that displays the operation of the copying machine.
It also includes an input key C1 for inputting the type of paper.

Note that the CPU 100 has an input/output interface 10.
Various drive mechanisms constituting the copying machine are further connected via 1, but these are omitted in FIG. 1 because they are not particularly relevant to the features of this embodiment.

The CPU 100 also includes a control ROM as a storage means.
102, font ROM 103 and RAM 104 are connected. The control ROM 102 is a read-only memory in which a control program for the electrostatic copying machine is stored. The font ROMIO3 is a read-only memory in which character data is stored in advance. When recording specific characters or numbers by the additional information recording means T, the specific characters or numbers are read from the font ROM 103 and stored in the buffer area 104a of the RAM 104.

The thermal transfer time suitable for the type of paper is determined by the control ROM10 above.
It is stored in 2. The thermal transfer time stored in the control ROM 102 is longer for paper with poor transfer properties. This is because increasing the thermal transfer time and applying more heat improves the transferability of the thermal transfer ribbon to paper.

The type of paper is manually input using the input key 01 by ranking the various types of paper used for copying into several levels depending on the degree of thermal transferability. The above data is determined in advance through experiments.

When you input the paper type to input key C1, CPU100
control RO according to the input paper type data.
Additional information is recorded on the paper by the additional information recording means T using the optimal thermal transfer time stored in M102.

A more specific example will be explained with reference to the waveform diagrams shown in FIGS. 2(a) and 2(b). The example shown in the figure shows a case where seven characters are printed on one line.

When input key C1 is used to input paper with good transfer properties, such as copy paper specified by the machine, the CPU
100 is a control ROM 10 as shown in FIG.
2, the thermal transfer time t of the paper with good transfer properties is
Additional information is recorded by the additional information recording means T as the output time of the output signals of strobes 1 to 7 corresponding to one line of recorded information.

On the other hand, if paper with poor transferability, such as plain paper, is input as the paper type using the input key C1, the CPU 100
As shown in Figure 2), the thermal transfer time t+α for paper with poor transfer properties (the time obtained by extending the thermal transfer time t for paper with good transfer properties by a) stored in the control ROM 102 is set as the new output time. , the additional information is recorded by the additional information recording means T. The extension time a can be changed in stages according to the type of paper, that is, the difference in transferability. The upper limit of the output time is not particularly limited, or it can be extended to about twice the output time t (ie, α-t) for paper with good transfer properties.

In addition, in order to extend the thermal transfer time of the thermal transfer ribbon,
For example, as shown in FIG. 3, the output signals of strobes 1 to 7 corresponding to one line of recorded information may be output repeatedly two or more times.

In addition, in the case of paper with good transfer properties, increasing the heating temperature of the platen roller will further improve the transfer property, so when you select a rank of paper with good transfer properties, increase the heating temperature of the platen roller. At the same time, the additional information may be recorded by the additional information recording means T by making the heating and transfer time shorter than the above-mentioned t.

Note that the image forming apparatus of the present invention is not limited to the embodiments described above.

For example, the additional information recording means T is not limited to the embodiment shown in the figure, but may employ various conventionally known configurations as long as additional information can be recorded on the paper using a thermal head and a thermal transfer ribbon. be able to.

Although the illustrated embodiment shows an electrostatic copying machine as an example of an image forming apparatus, the configuration of the present invention can be applied to other image forming apparatuses such as a laser beam printer.

In addition, various design changes can be made without changing the gist of the present invention.

<Effects of the Invention> The image forming apparatus of the present invention is configured as described above, and the control means is configured to control the thermal transfer time at the optimum thermal transfer time stored in the storage means according to the type of paper input to the input means. Since the additional information is recorded on the paper, it is possible to always record the additional information with a constant image density regardless of the type of paper.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the electrical configuration of an electrostatic copying machine as an embodiment of the image forming apparatus of the present invention, and FIG.
3 are waveform diagrams showing an example of the additional information recording operation in the above embodiment, and FIGS. 4 to 6 are sectional views showing the vicinity of the additional information recording means, which is the main part of the above embodiment,
FIG. 7 is a perspective view of the additional information recording means, and FIG. 8 is a schematic diagram showing the internal structure of the electrostatic copying machine. T... Additional information recording means, C1... Input means, 5.
...Thermal head, 100...CPU (control means), 102...Control ROM (storage means). procedure? tlj Official Patent Application No. 228635 of 1990 2, Name of the invention Image forming device 3 Relationship with the case of the person making the amendment Name of the patent applicant (615) Sanda Kogyo Co., Ltd. 4, Agent 6, Specification subject to amendment Contents of amendments to the Claims column and Detailed Description of the Invention column and Figure 2, Figure 7 of the drawings (1) The claims are amended as shown in the attached sheet. (2) The sentences from line 4 to line 16 of section 300 of the specification are amended to the following sentence. This invention provides an image forming apparatus equipped with additional information recording means for recording additional information on paper using a thermal transfer ribbon and a thermal head. The present invention is characterized by comprising an energization time control means for controlling the energization time to the thermal head when recording additional information by the additional information recording means in response to the output of the means. Effects> In the image forming apparatus of the present invention having the above configuration, the thermal transfer time is calculated according to the paper type output from the paper type output means. When the additional information is recorded by the additional information recording means, energization to the thermal head is controlled based on the calculated thermal transfer time. Therefore, additional information is recorded on the paper with a thermal transfer time suitable for the paper type. (3) The sentences from page 14, line 14 to page 16, line 16 of the specification are amended to the following sentences. In this embodiment, the thermal transfer time t+α (α or variable) by the thermal head 5 can be changed depending on the type of paper. In this way, even if the paper type changes, the additional information will be recorded with an easy-to-read density that corresponds to the paper type. In other words, for paper with poor transferability, the thermal transfer time is increased to apply a larger amount of heat to improve the transferability. The types of paper used for copying are classified into several ranks depending on the degree of thermal transferability, and are stored in advance in the control ROM 102. An example is shown in the table below. When one of the paper type numbers (1) to (5) is input by the human key 01, the CPU 100 reads out the rank stored in the control ROM 102 according to the manually entered paper type number. . Furthermore, when there is no input from the person Kaki-C, a predetermined rank, for example rank 1, may be read out. Then, the thermal transfer time t+α is calculated based on the read rank. Here, t+α is: t is the basic time, which is 0.512 m5ec, and α is the variable time, α. There is an × mark. ao =0.032m5ec. Therefore, for example (1) if Japanese-made high-quality paper is made manually,
Rank is 1". Thermal transfer time t+α is t+α=0.51
2+0.032X] =0.544m5ec. Also, if (5) blank paper is input, the rank is "]0". Thermal transfer time t+α is t+α=0.512+
0.032X], 0=0.832m5ec. In this example, the rank is 1 from “]” to “12”.
It is in two stages. A more specific example will be explained with reference to the waveform diagrams shown in FIGS. 2(a) and 2(b). When input key 01 is used to input a type of paper with good transfer properties, such as copy paper specified by the manufacturer (high-quality paper made in Japan), the thermal transfer time t+α1 is determined, and R
A M 1. ．． 04. Next, as shown in FIG. 2(a), when data for one row is given, the data is stored in the thermal head 5 by a latch signal. The thermal head 5 includes a large number of minute resistors as described above. These many resistors are divided into seven groups, for example, and are sequentially energized by strobes 1 to 7. Each strobe is given a thermal transfer time t+al which is read from the control ROM 102 and stored in RAM]-04. Accordingly, the resistor is given a time t+α for each group sequentially.
1 Electrification is applied and thermal transfer is performed. On the other hand, if input key C] manually selects a type of paper with poor transfer properties such as rough paper, the thermal transfer time for paper with poor transfer properties is t + a 1. O is determined,
Stored in RAM 104. Next, as shown in FIG. 2(b), when data for one row is given, the data is stored in the thermal head 5 by a latch signal. Subsequently, the seven resistor groups are sequentially energized by strobes 1 to 7. Each strobe]
~7 low active times are RAMl04, respectively.
The time stored in is t+α10. Therefore, each group of resistors is sequentially energized for a period of time t-1-a10 to perform thermal transfer. Note that from the low edge of the preceding strobe (for example, strobe 1), the next strobe (for example, strobe 2)
) is always kept constant even if the thermal transfer time t+α changes. Therefore, strobe l~
The time required to record one line of information processed by 7 is always constant. Note that instead of extending the low active time of strobes 1 to 7, strobes 1 to 7 are output by repeating them two or more times to record one line of information, as shown in Figure 3. Good too. In the above explanation, a large number of resistors are divided into seven groups,
The strobes 1 to 7 are sequentially energized. This is done in consideration of the fact that if all the resistors were energized at the same time, the drive current would be too large. However, if the operating power supply is large, all resistors may be energized at the same time. Further, the number of divisions of the resistor is not limited to seven, but can be divided into arbitrary groups. In that case, strobes as many as the number of divided croup are sequentially output. (4) Amend Figure 2 as shown in the attached sheet. 2. Claims: An image forming apparatus equipped with additional information recording means for recording additional information on paper using a thermal transfer ribbon and a thermal head, comprising: paper type output means for outputting the type of recording paper; An image forming apparatus characterized by:

Claims (1)

[Claims] 1. In an image forming apparatus equipped with an additional information recording means for recording additional information on paper using a thermal transfer ribbon and a thermal head, an input means for inputting the paper type and a thermal transfer time suitable for the paper type are stored. 1. An image forming apparatus comprising: a storage means for recording additional information on a sheet of paper; and a control means for recording additional information on a sheet of paper at a thermal transfer time stored in the storage means according to the type of sheet input to the input means.