JPS6348220B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording apparatus having a mechanism for mounting recording paper onto a platen by suction from inside the platen, for example, a drum.

For example, the applicant has previously proposed a recording device that has a mechanism for mounting recording paper on the drum by creating negative pressure inside the drum, but in such a recording device, it is not possible to change the size of the recording paper. may not be possible.

In other words, A4 size recording paper (plain paper, coated paper,
If you try to load recording paper of a smaller size onto a drum made for the purpose of loading transparencies (transparencies, etc.), a portion of the drum will not be covered by the recording paper. More air may flow into the drum, making it impossible to maintain the desired negative pressure inside the drum.

When such a situation occurs, the recording paper may float off the drum or fall off the drum, resulting in the recording paper not being properly mounted on the drum.

The present invention eliminates the above-mentioned conventional problems by controlling the suction force drawn from inside the platen according to the size of the recording paper.

A recording apparatus of the present invention that solves the above problems includes a platen having a suction means for generating suction force for adsorbing recording paper, a size specifying means for specifying the size of the recording paper, and a size specifying means for specifying the size of the recording paper. It is characterized by comprising a control means for controlling the suction force of the suction means according to a specification.

That is, in the present invention, by changing the suction force for mounting the recording paper on a platen such as a drum according to the paper size, the recording paper can be placed at the normal position on the platen regardless of the paper size. can be installed securely.

According to the recording apparatus of the present invention having such a configuration, the recording paper can always be mounted on the platen in a preferable state regardless of the paper size, so extremely stable recording can be performed on the recording paper of the desired paper size. It can be performed.

A preferred embodiment of the present invention will be described below with reference to one drawing.

FIG. 1 is a schematic external view showing a copying apparatus 11 to which the present invention is applied, FIG. 2 is a cross-sectional view taken along line 2A-2A in FIG. 1, and FIG. 3 is a cross-sectional view taken along line 3A-3A in FIG.
Both FIGS. 2 and 3 schematically show the arrangement of only the main parts of the copying apparatus 11. As shown in FIG.

The copying apparatus 11 includes a reading device 12 for reading information on a document, and a recording device 13 for recording information on recording paper.

The recording device 13 includes a drum 63 as a platen on which recording paper is mounted, and a suction pump 83 as a suction means for bringing the inside of the drum 63 into a negative pressure state. drum 63 by the suction force of suction pump 83 via
There is a mechanism on the top that attracts the recording paper.

The suction force of the suction pump 83 is controlled by a control means, which will be described later, so as to generate a suction force according to the paper size of the recording paper.

Next, the recording device 13 will be explained in more detail.

An opening 54 is provided in a part of the housing of the recording device 13, and a cassette 53 containing stacked recording papers 55 cut to a predetermined size is housed and fixed therein.

A shaft 5 is attached to the upper part of the cassette 53 installed in the casing.
A paper feed roller 56 fixed to an arm 58 rotatable about 7 is disposed. This paper feed roller 56 is constantly rotating and comes into contact with the top of the recording paper 55 stacked in the cassette 53 only when paper is being fed.When paper feeding is not required, the arm 58 is rotated upward. The paper feed roller 56
This is to prevent the recording paper 55 from coming into contact with the recording paper 55.

Note that the paper feed roller 56 is widely known in copying machines and the like, so a detailed explanation thereof will be omitted.

Reference numerals 59-1 and 59-2 indicate guide plates for guiding the recording paper fed out from the cassette 55, and the recording paper 55 guided by the guide plates 59
is sandwiched between a driven roller 60 and a driving roller 61, which constitute a timing roller, and is further fed out between guide plates 62-1 and 62-2, and is provided on the outside of a drum 63 that sucks and holds the recording paper 55. is guided into the opening 65 of the outer drum 64.

The drum 63 has a hollow cylindrical shape, and as shown in FIG. 3, one end is rotatably held in a bearing 74-1 by a shaft 73 fixed to the drum 63, and the other end is held in a holding frame. It is rotatable with respect to a barrel 75 fixed to the drum 74-2, and is held in an airtight state between the barrel 75 and the drum 63.

A pulley 76 is fixed to the end of the shaft 73, and a belt 80 is wound between the pulley 76 and a pulley 79 fixed to the rotating shaft 78 of a motor 77.
By driving the drum 63, the drum 63 is rotated in the direction of arrow D.

A large number of through holes 81 are provided in the circumferential portion of the drum 63, and by generating suction force by making the inside of the drum 63 a negative pressure than atmospheric pressure, the circumferential portion of the drum 63 is It is constructed so as to attract the recording paper 55.

For this purpose, a hose 82 is connected to the shaft tube 75, and the end of this hose 82 is connected to a suction pump 83. In the present invention, in order to maintain this negative pressure at a desired value regardless of the size of the recording paper, the suction force of the suction pump 83, which is the suction means, is changed depending on the size of the recording paper.

When the leading edge of the recording paper 55 is conveyed to the opening 65 by the timing roller while the pump 83 and motor 77 are being driven, this leading edge is attracted by the drum 63 and tries to rotate together with the drum 63. . While the area where the leading edge is wrapped around the drum 63 is small, the recording paper 55 is fed according to the rotational speed of the timing roller, and during this time the recording paper 55 is wrapped around the drum 63.
3, it slips by the difference between the circumferential speed of the drum 63 and the feed speed of the timing roller, but once it has been wound to a certain extent, it is wound around the drum 63 at the same speed as the rotation of the drum 63, and at this time, the one-way clutch 68 This causes the drive roller 61 to be in an idling state.

A cylindrical outer drum 64 having a slightly larger diameter than the drum 63 is arranged outside the drum 63. Both ends of the outer drum 64 are open, and the recording paper 55 is placed at the upper end. An opening 65 for drawing in and discharging ink is provided, and a slit 84 is provided on the side for moving an inkjet nozzle, which will be described later.

The outer drum 64 is composed of a fixed drum section 85 and a floating drum 86, and the floating drum 86 is supported by a shaft 87, so that the recording paper 55 is not jammed in the gap between the drum 63 and the outer drum 64. If an accident (jam) occurs in which the floating drum 86 is
It is constructed so that the recording paper 55 can be taken out by rotating it in the direction shown in FIG.

As mentioned above, the inkjet nozzle moves through the slit 84, and this inkjet nozzle is surrounded by a protective cylinder 89.

On the other hand, the base 91 has three guide rails 9 attached to the rotation center axis of the drum 63 and provided in parallel.
Since the head 90 is fixed to a movable base 99 slidably fixed on the rails 96 to 98, by moving the movable base 99 along the rails 96 to 98. It is possible to move within the slit 84 from one end of the drum 63 to the other end. A tank 100 filled with ink 99 is placed on the movable base 99, and the ink is supplied from the tank 100 to the ink jet nozzle through a pipe 101.

Recording is performed on the recording paper 55 wound around the drum 63 rotating at high speed by an inkjet nozzle that moves at a constant low speed along the guide rails 96 to 98. The same information as the original is recorded on the recording paper 55 by sequentially applying original signals obtained by the light receiver 35 to the original.

When the recording on the recording paper 55 is completed in this way, the pump 83 is stopped and the negative pressure inside the drum 63 is released and the pressure becomes the same as atmospheric pressure, or the negative pressure is made closer to atmospheric pressure. By doing so, the recording paper that was attracted to the drum 63 is separated, and when the leading edge of the recording paper reaches the opening 65, the recording paper 55 is removed.
is guided by the guide plates 62-1, 114 and protrudes into the ejected paper storage section 115, where it is stored. In this way, even without stopping the pump 83, a lid for introducing outside air into the hose 82 is provided on a part of the hose 82, and opening and closing of this lid is controlled by a plunger to maintain a negative pressure state inside the drum 63. It can be controlled.

As described above, in the copying apparatus according to the present embodiment, the suction force of the pump 83 is controlled according to the size of the recording paper, so that the negative pressure state in the drum 63 becomes a state suitable for sucking the recording paper. This negative pressure control will be described in detail below.

FIG. 4 is a circuit diagram showing an example of a negative pressure control circuit applied to the present invention.

In FIG. 4, reference numeral 187 indicates the pump 8.
Stator windings 188 and 189 are provided opposite to this rotor 187.

The 100V AC power applied to the terminal 192 is rectified by the full-wave rectifier 193, and then sent to the SCR 190,
191, the voltage is changed to alternating current again and a variable voltage is applied.

Therefore, this motor is operated by a known trigger control circuit 1.
By controlling the phase angle of the gate pulse applied to the SCRs 190 and 191 from 94, the torque can be controlled, so that the suction state by the pump 83, in other words, the negative pressure state within the drum 63 can be controlled.

The trigger control circuit 194 includes a resistor 195.
1 to 195-3 or 196-1 to 196-3
The structure is such that any one of the resistors can be connected to the resistor.

That is, switches 7-1 to 7-3 are paper size specification keys, and 7-1 is a key for specifying A4 size.
7-2 is the key to specify B5 size, 7-3 is A
5 key to specify size, resistance 195-1
The resistance value of ~195-3 is 195-1>195-
Set so that 2>195-3.

With this configuration, the suction force when pressing key 7-2 will be stronger than the suction force when pressing key 7-1, and the suction force when pressing key 7-2 will be stronger than the suction force when pressing key 7-2. The suction force when pressing 7-3 increases, and the smaller the area of the recording paper wrapped around the drum 63, the greater the suction force can be.

Therefore, by appropriately selecting the values of the resistors 195-1 to 195-3, regardless of the paper size,
The recording paper can be wound around the drum 63 in the same state.

Next, an outline of the internal configuration of the reading device 12 will be explained with reference to FIGS. 2 and 3.

Inside the housing 29 of the reading device 12, three guide rails 30-1, 30-2, 30-3 are provided in parallel with each other.
A sliding member 31-1 is slidably provided on the guide rail 30-3, and a sliding member 31-1 is provided on the guide rail 30-3.
A sliding member 31-2 is slidably provided, and a flat base 32 is fixed to the sliding member 31.

The arms 3 extend upward from both ends of the base 32.
3-1 and 33-2 are extended, and between these arms 33 is a translucent rod-shaped body (a converging light transmitting body) whose refractive index decreases parabolically from the center in the radial direction. ) are arranged in a straight line and a lens 34 is fixed. Incidentally, such a lens is not limited to the above-mentioned convergent light transmitting body, but may be any lens having a linear arrangement of minute lenses capable of obtaining a same-magnification erect image.

A light receiver (for example, CCD) 35 in which a large number of light receiving elements are linearly arranged is arranged on the base 32, and an optical image of the document placed on the document table 14 is transmitted to the light receiver by the lens 34. It is constructed so that the image is formed on 35.

Further, between the arms 33, a rod-shaped lamp 36 is provided which is approximately equal to or longer than the lens 34, and is approximately parallel to the lens 34.
The reflecting mirror 37 is fixed so that the light emitted from the mirror 6 effectively illuminates the document table 14.

The base 32 having such a configuration is connected to the guide rail 30.
Information on the document placed on the document table 14 is sequentially imaged on the light receiver 35 by moving the document table 14 . Therefore, if the clock signal is applied sequentially and the light receiving elements are sequentially read out, a sequential signal obtained by raster scanning the original can be obtained from the light receiver 35.

Further, the reading device as described above is housed in a separate housing from the recording device 13, and
Two guide grooves 27-1, 27-2 provided at the top of
The upper part is movable. and,
In the steady state of the reading device, the reading device 12 is locked by the locking device 28 shown in FIG.
is fixed in a position as shown in FIG.

As detailed above, in the recording apparatus according to the present invention, the negative pressure inside the drum is changed according to the paper size, so that the recording paper is always attracted to the drum in a desirable state, so that it is possible to maintain the normal position. It is possible to record on the folded recording paper.

In the above embodiment, the paper size was specified by inputting the size of the recording paper using the operation switch, but of course, as is normally done, the cassette is provided with a protrusion for size determination, and the cassette is used for copying. The size may be specified by inserting it into the device.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a copying apparatus according to an embodiment of the present invention, FIG. 2 is a sectional view taken along 2A-2A in FIG. 1, FIG. 3 is a sectional view taken along 3A-3A in FIG. 2, and FIG. FIG. 2 is a negative pressure control circuit diagram according to an embodiment of the present invention. 7-1, 7-2, 7-3...Paper size specification key, 11...Copying device, 12...Reading device, 13
...recording device, 63...drum, 83...pump.

Claims (1)

[Claims] 1. A platen having a suction means that generates a suction force for adsorbing recording paper, a size designation means for specifying the size of the recording paper, and controlling the suction force of the suction means according to the designation of the size designation means. A recording device characterized in that it has a control means for controlling.