JPS61156161A - Color recording device - Google Patents

Abstract

PURPOSE:To obtain images which are free from positional deviation, by forming gears to be fixed to photosensitive drums and intermediate drums by using the same mold or by simultaneous integral working and marking the gears at the same position, and then, selecting the phase of the marked position. CONSTITUTION:&?Gears 8a-8c of the same diameter are fitted to the revolving axes 7a-7c of each photosensitive drum 3a-3c and intermediate gears 9a and 9b are prepared so as to have the same diameter as the gears 8a-8c have, and then, the gear 8c is driven by means of a driving gear 10. Gears of the same shape which are formed by using the same mold or integrally worked and formed are used for the gears 8a-8c and 9a and 9b so as to make errors, such as eccentricity, etc., the same and the gears are marked 32 at the same position. The eccentric phases of the first gear 8c and intermediate gear 9b are made the same and those of the gears 8b and 9a are deviated by 180 deg.C from each other. The eccentric phase of the last gear 8a is further deviated by 180 deg.C. Therefore, the speed deviation quantity becomes the same as the displacement quantity when each point of each photosensitive body reaches the transferring position and to positional deviation occurs in the images.

Description

[Detailed Description of the Invention] Karidama Tateno The present invention forms color-separated optical images of color images on a plurality of photoconductor drums individually, and transfers the developed images of each photoconductor drum onto a single sheet of transfer paper. The invention relates to color recording devices such as copying machines, facsimile machines, and printers.

Conventionally, it is equipped with a plurality of photoconductor drums, a charging device attached to each photoconductor drum, a 1x illumination exposure optical system including a focusing light transmitting array, a developing device, a transfer device, etc. A color copying apparatus that forms separated optical images on each photoreceptor drum and transfers the developed images on each photoreceptor drum onto a sheet of transfer paper is known, for example, from Japanese Patent Laid-Open No. 57-85066.

In a color copying apparatus using a plurality of photoreceptor drums, if the corresponding position of each photoreceptor drum is not accurately aligned with a predetermined position on the transfer paper, color misregistration will occur. Although the accuracy of various mechanical parts can be improved to a certain degree, it is inevitable that variations will occur in the movement of each mechanical part when assembled and operated.

For example, when three photoreceptor drums are rotationally driven, the driving speed can be made the same for each, but for example, one of the drums can be driven at the same speed.
During rotation, even if the speed of one rotation is the same for all three drums, variations in speed during one rotation are unavoidable. Therefore, what should be rotating at the same speed actually appears on the transfer paper as a color-shifted image.

In conventional copying apparatuses, the cycles of speed fluctuation of each of the plurality of photosensitive drums are different, so that a visually perceptible shift inevitably occurs between images at the fastest speed position and the slowest speed position.

An object of the present invention is to solve the above-mentioned problem of image position deviation in conventional recording apparatuses including copying machines, facsimile machines, printers, etc. having a plurality of photosensitive drums.

1. In order to achieve the above object, the present invention provides a gear train consisting of gears of the same shape, in which a gear fixed to a photoreceptor drum and an intermediate gear meshing with the gear are formed by molding the same mold or simultaneous integral processing. It has a driving gear that meshes with one of the gears and is driven by one motor, and the gears of the gear train are marked at the same position during molding, and each gear is set so that the mark is at a predetermined phase position. When the gears are assembled, the number of teeth ratio Z2/Z1 between the number of teeth 21 of the drive gear and the number of teeth 22 of the gear of the gear train with which this drive gear meshes is set to approximately 1.7.
~2.1 is characterized by a drive device selected as follows.

The present invention will be specifically explained below based on examples.

In FIG. 1, a document 1 is placed on a transparent document table 2 with its image surface facing downward. The document is illuminated and scanned by the reciprocating movement of the document table 2.

A first photoreceptor drum 3a, a second photoreceptor 3b, and a third photoreceptor drum 3C are arranged below the movement path of the document table 2 at regular intervals from the left in the figure, and each photoreceptor drum and the document An exposure device 4a, a second exposure device f, tb, and a third exposure device 4c are arranged between the moving path of the table 2 and the moving path of the table 2, respectively. The distance between the axes of each photosensitive drum can be selected to be 1/2 of the circumferential length of the photosensitive drum, the same length as the circumferential length, or an integral multiple of the circumferential length.

All of the photosensitive drums are formed to have the same outer diameter.

The exposure devices W4a to 4c each include a lamp 5 and a focusing light transmitter 6.
It is equipped with

It is obvious that a lens system can be used in the exposure apparatus in a well-known manner.

The lamp 5 of the first exposure device 4a produces red light or emits it through a red filter, the lamp of the second exposure device 4b produces green light or emits it through a green filter, and the lamp ° of the third exposure device 4c emits blue light. or irradiate it through a blue filter.

The photosensitive drums 3a to 3 are
Since the image formed on c is a mirror image of the image of the original 1 on the original platen 2, that is, the image is not reversed in the scanning movement direction A of the original, the photoreceptor drums 38 to 3c each have a mirror image with respect to the image of the original 1 on the original platen 2. rotated in the direction

A charging device 11, a developing device 12, a pre-transfer static elimination lamp 13, a transfer charger 14 as a transfer device, and a static elimination lamp 15 are arranged around each of the photosensitive drums 3a to 3C in a known manner. In order to clarify the relationship with each photoreceptor drum, a is for the member related to the first photoreceptor 3a, b is the member related to the second photoreceptor drum 3b, and b is a member related to the third photoreceptor drum 3C. is given the subscript C.

The developing device 12a of the first photoreceptor drum 3a that is exposed to red light contains a cyan developer that is a complementary color to the red light, and the second photoreceptor drum 3b that is exposed to green light contains a cyan developer.
The developing device 12b of the third photosensitive drum 3C, which is exposed to blue light, contains a magenta developer that is a complementary color to green light, and the developing device 12C of the third photosensitive drum 3C that is exposed to blue light contains a yellow developer that is a complementary color to blue light. be accommodated. It is also possible to arrange four photosensitive drums instead of the three shown in the figure. In this case, a black developer may be used as the developer.

During the second movement of the original, the exposure devices 4a, 4b, and 4C sequentially expose the original, but there is a timing delay required for the movement of the original, and the image developed by the color-separated light image formed on the photoreceptor drum is not transferred to the transfer paper. There is also a time difference in transfer timing.

When the distance between the axes of the photosensitive drums is selected to be 1/2 of the circumferential length of the drum, the distance between the illumination positions for the document is also set to be 1/2 of the circumferential length of the drum. The manuscript is the first i! After exposure at the first illumination position by the optical device 4a, at the second illumination position by the exposure device 4b.
When the first photoreceptor drum 3a moves to the illumination position and starts exposure, the first photoreceptor drum 3a has already rotated half a rotation, and a developed image is formed on the surface of the photoreceptor drum. Similarly, when the document 2 moves to the third illumination position by the third exposure device 4c and exposure begins, the first photosensitive drum 3a has rotated once and the second photosensitive drum 3b has rotated half a rotation.

When using a lens system as an exposure device or using a structure in which the image of a focusing light transmission body is reversed with a mirror, or when a laser beam is irradiated onto a photoreceptor drum using an image information electric signal as in printers, facsimiles, etc. In some cases, the photoreceptor drums 3a to 3c may be rotated counterclockwise in the figure. In this case, the transfer paper is transferred by the conveyor belt 16 to the first photoreceptor drum 3a, the second photoreceptor drum 3b, and the third photoreceptor drum 3C in order, so that there is a difference in exposure time and transfer time between each photoreceptor drum. Since these values match, each of the photosensitive drums 3a to 3c can be transferred onto the transfer paper after about half a rotation. On the other hand, in the example shown in FIG. 1, the photosensitive drums 3a to 3c are rotated clockwise in the figure, so the transfer IE 17 is transported from the paper feed cassette 18 on the right side of the figure by the paper feed roller 20 and the registration roller 21. It is sent out onto the belt 16 and is conveyed by the conveyor belt 16 from right to left in the figure. The transfer paper is placed on the third photoreceptor drum 3C, contrary to the above example of the exposure device (not shown).
% The transfer chargers 14c, 14b are in contact with the second photosensitive drum 3b and the first photosensitive drum 3a in this order.
, 14a, the images are sequentially overlapped and transferred.

The transfer paper that has been transferred by the first photoreceptor 3a is sent to a separated pair of fixing rollers 22, and after being fixed, it is discharged to the outside of the machine by a paper discharge roller 23.

Electrostatic latent images are formed on each photoreceptor drum 3a to 3c sequentially from the first photoreceptor 3a with a delay of half the circumference of the photoreceptor drum, and the developed images obtained by each developing device 12a to 12C are also delayed by the same time. have. If this delay in image development between the photoreceptors is added up sequentially from the third photoreceptor 3c side, it will be delayed by half the length of the photoreceptor drum. Moreover, since the distance between the transfer positions of each photoreceptor is maintained at half the circumference of the photoreceptor drum, taking into consideration the movement of the transfer paper, the time will be shifted by one rotation of the photoreceptor drum. Overlapping transfer is possible without image shift.

As can be seen from the above description, each of the photoreceptors 3a to 3C is 4
It will rotate. After exposure and development are performed in the first rotation, the first photoreceptor 3a continues to rotate while holding the developed image until the transfer to the second photoreceptor 3b and third photoreceptor 3c is completed. Further, after the second photoreceptor 3b is exposed and developed during the first and second rotations, the third photoreceptor 3C
Rotate while holding the visible image until the transfer is completed. Since it would be undesirable for the photoreceptors rotating while maintaining their visible images to be exposed to light, as soon as the exposure work for each photoreceptor is completed, a shutter 24a placed at the exposure position of each photoreceptor, 24b and 24C are rotated 2 to the extent that they block the optical path from the convergent optical transmitter array 6, as shown by the chain lines in FIG. Incidentally, since the latent image formed by exposure to the third photoreceptor 3C is transferred immediately after being developed, there is no need to hold the developed image for a long time, so there is no need to operate the shutter 24C.

FIG. 2 shows an example of a drive device that rotationally drives each of the photosensitive drums 3a to 3C. Gears 8a, 8b having the same diameter are attached to the rotating shafts 7a, 7b, 7c of each of the photoreceptor drums 3a to 3C,
8C is installed, and the gears of adjacent photosensitive drums are drivingly connected to each other by meshing one intermediate gear 9a, 9b, and the gears 13a, 3b, 8c and intermediate gears 9a, 9.
b forms one gear train. Intermediate gears 9a, 9
b is formed by a gear having the same diameter as the gears 8a to 8c.

Each gear is driven by a drive gear 10 that meshes with a gear 8C provided on the third photoreceptor drum 3C. The drive gear 10 is attached to the shaft of the motor 25, but it can also be driven indirectly by the motor 25 via another gear. The drive gear 10 drives a gear 2B attached to a drive roller 27 of the conveyor belt 16 via an idler 26. By rotating the driving gear 10 in FIG. 2 counterclockwise, the gears 8a to 8c and the photosensitive drums 3a to 3c are rotated clockwise.

The drive gear 10 can also be arranged to mesh with the gear 8a of the first photoreceptor drum.

The photoreceptor drums 3a to 3C can be driven by a transmission means such as a belt, but slippage or stretching of the belt or the like may cause movement deviations between the plurality of photoreceptor drums, causing image positional deviation. Therefore, in the present invention, a gear device is used as the transmission means.

Theoretically, by using a gear system, there will be no deviation in movement between the plurality of photoreceptor drums 3a to 30, but in practice, there is a machining error due to the eccentricity of the gears, etc. The peripheral speed of the gear fluctuates.In other words, the speed at which the gear makes one revolution is as per theory, but if you look at the peripheral speed of the gear at the meshing point of the two teeth, it will fluctuate during one revolution due to eccentricity, etc. Fluctuations in the peripheral speed of one gear directly result in fluctuations in the peripheral speed of the next gear, and the fluctuations in the peripheral speed of the next gear itself are superimposed.When considering a gear train in this way, each gear This means that even if the time for one rotation of each photoreceptor drum is the same, each point on the circumferential surface during that time has different speed fluctuations depending on each photoreceptor drum. When viewed in relation to the transfer paper, this causes a phenomenon in which a predetermined position of each photoreceptor reaches the transfer position before or after a predetermined time due to speed fluctuations. Image shift due to slight positional deviation, In other words, even though color shift may not be felt visually, it is possible to avoid a state in which a visual discrepancy will be felt between an image transferred at the maximum advance and an image transferred at the maximum delay relative to the theoretical speed among speed fluctuations. do not have.

At present, it is difficult to avoid fluctuations in the circumferential speed at each point on each of the photosensitive drums 3a to 3c. Therefore, the present invention attempts to solve this problem by making the speed fluctuations of each photosensitive drum the same when viewed from the time of transfer to the corresponding position on the transfer paper. In other words, even if there is circumferential velocity variation, the velocity variation of multiple photoreceptor drums is exactly the same, and if this state is maintained during transfer, the color separation images of the same image will be transferred to the same position on the transfer paper, and the image position will be No misalignment or color shift occurs.

In order to match speed fluctuations of the photoreceptor, it is necessary to equalize errors occurring in the gears. Therefore, in the present invention, the gears 8a to 8c and the intermediate gear 9a, which are attached to the shaft of each photoreceptor,
9b are formed by the same molding using the same mold, or the same shape is used, that is, the same shape gears are integrally processed and molded at the same time. This ensures that all gears have the same error even if there is an error such as eccentricity.

Even if such gears of the same shape are used, speed fluctuations cannot be made to match if the gears are assembled without considering the relative positional relationship.

Therefore, a mark 29 is attached to each gear at the same position during molding or immediately after molding, as shown in FIG.

The circumferential speed fluctuations of each photoreceptor are roughly affected by eccentricity.
It can be seen as a periodic fluctuation in which one cycle is rotation. If we look closely, there are minute fluctuations in between, but when we are targeting shifts that affect visual perception, we have found that almost satisfactory results can be obtained by considering periodic fluctuations due to eccentricity.

In the example of FIG. 1, a fluctuation curve as shown in FIG. 3 is obtained. FIG. 3(a) shows the fluctuation of the deviation from the reference peripheral speed of the first photoconductor, FIG. 3(c) the second photoconductor, and FIG. 3(e) the third photoconductor, respectively. The horizontal axis represents the rotation angle, and the vertical axis represents the amount of variation in speed deviation. FIG. 3(b) shows the first photoreceptor, the third
Figure (d) shows the displacement amount of the second photoconductor, and Figure 3 (f) shows the displacement of the third photoconductor, which is expressed as a deviation from the position that should be reached when there is no speed variation, and the horizontal axis is the rotation angle. , the vertical axis represents the amount of displacement.

In the above example, the first photoconductor 3a reaches the transfer position after 2.5 rotations after exposure, the second photoconductor 3b reaches the transfer position after 1.5 rotations, and the third photoconductor 3c reaches the transfer position after 1.5 rotations after exposure. The transfer position is reached after 5 rotations. Therefore, if the speed deviation amount and the displacement amount when each point of each photoreceptor reaches the transfer position are the same, no image position shift occurs. In order to do this, it is only necessary to select the period, amplitude, and phase relationship of the speed fluctuation of each photoreceptor as shown in FIG. 3, that is, as shown in FIG.
The first photoreceptor is exposed at point A1 in (b), and the transfer position is reached at point B1 after 2.5 rotations.

be. In this case, β is the maximum speed deviation amount (%), 鈛 is the average circumferential speed of the first photoreceptor in m/sec, and f is the frequency of speed fluctuation (Hz). In FIGS. 3(c) and 3(d), the second photoreceptor is exposed at point A2, and the transfer position is reached at point 82 after 1.5 rotations. At this time, the speed deviation is zero,
Displacement is maximum quantity dependent.

R92 indicates the average peripheral speed van/sec of the second photoreceptor, where v, , L=vp. Figure 3 (e
), (f), the third photoreceptor is exposed at point A3 to 0.5
The transfer position is reached at 83 points after rotation. It is 83 points. ■3. indicates the average circumferential speed of the third photoreceptor, and in this case, V=v, □=Vp.

If the relative rotational position of each photoreceptor and the configuration of the gear drive system are considered so that the period, amplitude, and phase relationships as shown in FIG. 3 are taken into consideration, no positional shift of the image will occur. By using gears having the same shape obtained by simultaneous integral processing or molding using the same mold as described above, the period and amplitude of speed fluctuation can be adjusted as shown in FIG. The problem here is to set the phase as shown in FIG.

In FIG. 2, the average radius of the pitch circle of the drive gear 10 is RO, and the first gear 8a is fixed to the shaft of the first photoreceptor 3a.
R1 is the average radius of the pitch circle of the second gear 8b fixed to the shaft of the second photoreceptor 3b, R2 is the average radius of the pitch circle of the second gear 8b fixed to the shaft of the second photoreceptor 3b,
The average radius of the pitch circle of the third gear 8c fixed to the shaft of the photoreceptor 3c is R3, the average radius of the pitch circle of the first intermediate gear 9a meshing with the first gear 8a and the second gear 8b is R4,
The average determination of the pitch circle of the second intermediate gear 9b that meshes with the second gear 8b and the third gear 8c is set as R5, and the runout or eccentricity of the pitch circle of each gear is determined as follows: ro for the driving gear, rl for the first gear, rl for the first gear, The second gear is R2, the third gear is r3, the first intermediate gear is R4, and the second intermediate gear is R5.

The angular velocity ω0 of the drive gear 10 is set to be constant, and the circumferential velocity of each gear is observed. In the gear train shown in Fig. 2, the drive gear 1° is the third gear 7c.
However, to simplify the explanation, an example will be described in which the drive gear 10 meshes with the first gear 7a.

At the meshing point of the driving gear and the first gear, the circumferential speed of the driving gear and the first gear is Va1 = ω0 At circumferential speed Va1' = 6) I
R1°=ωIL/2 Circumferential speed Va2=ω4R4'' - Sick Toy-4 edition u), and circumferential speed Va2'=ω2 R2'=
IJ12 II/2 At the meshing point of the second intermediate gear and the third gear, the peripheral speed V a 3 = tJr・Rr'=(iJy (4
fry-ta). Since ω3 = ω1, the circumferential speed v2 of the third photoreceptor becomes VD"4 = 171.

The exposure position of the first photoconductor is θ=ωt=5π (2.5 rotations)
The exposure position of the second photoconductor is θ = ωt = 3π (1.5 rotations) (from θ = π after exposure of the first photoconductor to θ = 4π at the time of transfer). ) The theoretical deviation of the distance j1112' moved between ) is ΔL, ~2=ΔI,
x-ΔL2 The exposure position of the third photoreceptor is θ=ω[-π(0,
5 rotations) (from the position of θ=2π after exposure of the first photoconductor to θ-3π at the time of transfer), the positional deviation Δ of the distance I13'' moved by -1 is Δ2..=ΔL1-ΔL3 Second exposure The positional deviation Δi, 24 between the images of the body and the third photoreceptor on the transfer paper is ΔL2-′) = ΔJ12-Δi, 3. From this, the positional deviation is determined by the rotational phase.

Eccentricity of the first to third gears and the first to second intermediate gears ×〃 is r
When the eccentricity of the driving gear x z is r□, an experiment was conducted by changing the eccentricity phase of each gear, and the results shown in FIG. 4 were obtained. The maximum eccentric position of the gear is indicated by a mark in Fig. 4(a). We experimented with three combinations of eccentricity phases, A-C, and obtained the results shown by straight lines A, B, and C in Fig. 4(b), respectively. It was done.

In the figure, the horizontal axis represents the value of rl, and the vertical axis represents the positional deviation Wfl between the first photoreceptor and the second photoreceptor. Line A represents the gear arrangement of B, line B represents the gear arrangement of B, and line C represents the gear arrangement of C. The results of the gear arrangement are shown. This revealed that arrangement A had the smallest positional deviation.

Although the figure shows the first and second photoreceptors, the same thing can be said between the second and third photoreceptors.

Place a second mark 29 at the position of the gear, for example at the maximum eccentric position.
Assuming that it is filled in as shown in the figure, the eccentric phase of each gear can be arranged as shown in FIG. 2 to minimize positional deviation. Since the relationship between the drive gear and the first photoreceptor is different between the above explanation and FIG. 2, the phase of the first intermediate gear is 180°.
However, the results shown in Figure 4 are obtained according to the drive order from the drive gear, so applying this results in the second
It will look like the figure. In the gear transmission order, the first gear and the intermediate gear meshing with it have the same eccentric phase, the next gear and the next intermediate gear meshing with it have a 180° phase shift, and the next gear has a further 180° phase shift.

When four photoreceptors are used, the next intermediate gear is set in the same phase as the third drum shaft gear, and the last gear is further shifted in phase by 180 degrees. If more photoreceptors are used, the phases can be determined sequentially in the same way.

By marking each gear at the same eccentric position, the relative phase can be selected during assembly, and it is not necessary to mark the maximum eccentric position as described above.

Marks can be placed at the same position during mold molding or simultaneous processing.

In the embodiment shown in the figure, the distance between the photoreceptors is set to the circumferential length of the photoreceptor drum.
However, it can also be arranged at the same length as the circumference. In this case, the eccentric phases of the gears are not arranged with a phase shift of 180° as shown in FIG. 2, but are arranged so that they are in the same phase position.

This makes the speed phase of each photoreceptor drum the same. For example, if a drive gear for driving these gears is provided coaxially with the first photoreceptor drum 3a and the gear 8a, and the driving gear is configured to be driven from a motor shaft, the first photoreceptor drum 3a is driven by the drive gear. It will be directly affected by speed fluctuations such as eccentricity.

However, the second photoreceptor drum 30 and the third photoreceptor drum 3C
is further affected by the eccentricity of each gear after gear 8a, and there is no way to deal with speed fluctuations of the three photosensitive drums.

Therefore, a gear attached to the output shaft of the motor is additionally arranged in the above gear train with a drive tooth ratio of 10.

In this way, speed fluctuations due to eccentricity of the drive gear 10 are transmitted to all of the gears 8a to 8C, and therefore the first to third gears
It will be transmitted to the photoreceptor drums 3a to 3C. The number of teeth of the drive gear 10 is 21, and the gear 8 with which the drive gear 10 meshes
When testing the influence of the tooth number ratio Z2/Z1 with respect to the number of teeth C (22) on positional deviation, results as shown in FIGS. 5 and 6 were obtained. To simplify the explanation, an experiment will be described in which the drive gear 10 is meshed with the gear 8a of the first photoreceptor drum. In this case, it can be easily inferred that the same results as those in FIG. 2 can be obtained with respect to the problem of positional deviation, except that the order of transfer to the transfer paper is different.

FIG. 5(a) shows the relationship between the maximum positional deviation between the first photoreceptor drum 3a and the second photoreceptor drum 3b and the tooth number ratio Z2/Z, and the vertical axis represents the deviation (m). The horizontal axis is the tooth ratio N
= Z2/Zl, and curve A is ro =0.025 f
i, curve B shows the case where ro=Q, Q5m.

FIG. 5(b) shows the first photoreceptor drum, the third photoreceptor drum,
FIG. 5(C) shows the maximum positional deviation between the second photoreceptor drum and the third photoreceptor drum, both of which are ro = 0.025.
The change in case of m is shown. The vertical and horizontal axes are the same as in FIG. 5(a).

FIG. 6 shows the maximum positional deviation in a state in which all the positional deviations of 3M shown in FIG. 5 are combined, the vertical axis shows the deviation (crane), and the horizontal axis shows the tooth number ratio N=Z2/Zx.

From the results shown in FIG. 6, it was found that when the tooth ratio N was in the range of 1.7 to 2.1, excellent results were obtained in which the positional deviation was 0.075 or less. From this, the driving gear lO
For gears 8a to 8C, the gear ratio N=Z2/Z is 1.
7 to 2.1.

■ Using gears of the same shape formed by the same molding or integral processing according to the present invention, a mark is attached to the same position on each gear, and the phase of the position of the mark is selected, and the driving gear and the photoreceptor drum are By the simple means of selecting a tooth ratio between the two, it has become possible to create a color recording device that is capable of producing images without misalignment without the use of additional equipment.

[Brief explanation of the drawing]

FIG. 1 is a schematic front sectional view of an embodiment of a color copying apparatus according to the present invention, FIG. 2 is a diagram showing a gear train for driving the photosensitive drums, and FIG. 3 is a diagram showing the speed of each photosensitive drum. FIG. 4 is a diagram showing the relationship between the eccentric phase of the gears of the gear train of the photosensitive drum and the positional deviation;
Figure 5 is a diagram showing experimental results showing the tooth ratio between the drive gear and the gear of the photoreceptor drum and the state of positional deviation between each photoreceptor drum, and Figure 6 is a diagram showing the positional deviation of all photoreceptor drums and the drive. FIG. 6 is an experimental result diagram showing the relationship between the tooth number ratio between a gear and a photoreceptor gear. 3a, 3b, 3c...Photosensitive drums 4a, 4b, 4c...Exposure devices 8a, 8b, 8cm--Gears 9a, 9b...Intermediate gear 10...Drive gear 11...Charger ( Charging device) 12a, 12b
, 12cm developing device 17...Motor 22a, 22b, 22c...Transfer charger (transfer device) N: Teeth ratio procedural amendment April 16, 1985

Claims (1)

[Claims] (1) Equipped with a plurality of photoreceptor drums, a charging device, an image exposure device, a developing device, and a transfer device attached to each photoreceptor drum, and the color-separated optical images of color images are individually transferred to the photoreceptor drums. In the driving device of a color recording device that transfers the developed images of each photoreceptor drum onto a single sheet of transfer paper, the gears are fixed to the shaft of each photoreceptor drum, and each photoreceptor drum is arranged at the same interval. and one intermediate gear each disposed in mesh with the gears of adjacent photoreceptor drums, a drive gear meshing with any one of the gear of the gear train and the intermediate gear, A driving means is constituted by one motor that drives a driving gear, each gear of the gear train is formed by a gear of the same shape formed by molding the same mold or simultaneous integral processing, and the number of teeth of the driving gear is Z_1. A color recording device characterized in that a ratio Z_2/Z_1 between the number of teeth Z_2 of a gear of a gear train meshing with the driving gear is selected to be 1.7 to 2.1.