JPH0229029B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a recording device or a copying machine, and more particularly to a recording medium processing device that attaches and detaches a sheet-like recording medium to a recording drum of a recording device or the like.

Prior art and its problems In a drum-type recording device that uses a recording drum, it is necessary to automatically feed recording paper (recording medium) from a recording paper stack to the drum, attach it to the drum, and separate it from the drum after recording. It is. A conventional technique used for automatic paper feeding is to utilize the frictional force of rubber rollers or belts. These disadvantages include problems such as paper jams, double feeding, skew feeding, etc. of the recording paper due to differences in the weight and surface condition of the recording paper. Therefore, this technique is not suitable when different types of recording paper are used. Another paper feeding technique utilizes vacuum force, as disclosed in Japanese Patent Application Laid-Open No. 51-101719. This paper feeding device has a rotary cam and a suction means driven by the cam via an arm, and is configured to suction the topmost sheet of a recording paper stack and supply it to a set of transfer rollers. This device has the disadvantage that it often feeds more than one sheet of recording paper at the same time. Furthermore, since the recording paper is sent to the next stage via a transfer roller, it also has drawbacks such as paper jams and skewed feeding, similar to the above-mentioned techniques.

For example, as an automatic recording paper loading technique,
Some of these are disclosed in Japanese Utility Model Publication No. 49-75345 and Japanese Utility Model Application Publication No. 53-56826. In the former, holding means is provided on the surface of the drum along its axial direction to hold the leading edge of the recording paper sheet. This holding means opens to receive the leading edge of the sheet by the action of a cam at a particular rotational position of the drum. The recording paper sheet held by the holding means is wound around the drum as the drum rotates. With this technique, it is difficult to obtain high quality recorded images because the sheet is not mounted tightly against the drum surface. In the latter, another holding means is provided to hold the trailing edge of the sheet. This technique presents a new problem in that the size of recording paper that can be used is limited.

OBJECTS OF THE INVENTION One object of the present invention is to provide a recording medium processing device that can automatically process recording media for a drum-type recording device.

Another object of the present invention is to provide a recording medium processing device that can handle different types of recording media.

Still another object of the present invention is to prevent paper jams in recording media;
An object of the present invention is to provide a recording medium processing device that can minimize the possibility of paper feeding problems such as double paper feeding.

Other objects and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings.

SUMMARY OF THE INVENTION The present invention is a recording medium processing device for a recording apparatus that loads a sheet-like recording medium from a recording medium stack onto a drum and removes it from the drum after recording is completed. The recording medium processing device of the present invention includes a notch provided on the surface of the drum along the axis of the drum, a plurality of through holes provided in the notch portion of the drum, and a vacuum pump means for evacuating the inside of the drum. , feeding means for feeding the leading edge of the topmost recording medium of the recording medium stack into the notch portion of the drum. Therefore, the front end of the recording medium is attracted to the through hole in the notch portion of the drum, and as the drum rotates, the entire recording medium is attracted to the periphery of the drum.

Embodiment An inkjet printer is a type of recording device that can perform both monochrome and color recording. FIG. 1 shows a simplified diagram of an inkjet printer to which the present invention is applied. In FIG. 1, a sheet of recording paper is picked up from the recording paper stack 14 by the paper feed means 20 and adhered to the drum 6. In FIG. The paper feeding means 20 includes a pick 1
6 and a vacuum pump pipe 18, the vacuum pump pipe is a three-stage centrifugal blower (three-stage centrifugal blower).
and a vacuum pump means (not shown), such as a centrifugal blower. The drum 6 is also connected by the hose 5 to the same vacuum pumping means. The air within the drum 6 is released to the outside. A plurality of through holes are provided on the surface of the drum 6 in order to attract the recording paper lifted by the paper feeding means 20 and hold it closely around the drum. When the front end of the recording paper is attracted to the drum 6, this front end begins to rotate together with the drum. As a result, the recording paper wraps around the drum. An idler roller 12 is provided to assist in loading the recording paper. After the recording paper has been loaded, the rotational speed of the drum 6 is accelerated to a speed suitable for recording by the inkjet head mounted on the carriage 2. Carriage 2 is on rails 3 and 4
and are scanned axially along these rails. When recording is completed, the drum 6 is decelerated. The recorded recording paper is peeled off from the drum 6 by the removal claw 26 and sent to the output tray 22. A pair of idlers to assist in paper removal.
A roller 30 is provided.

Two embodiments of the paper feeding means 20 are shown in FIGS. 2A and 2B. The paper feeding means 20 has means for solving the problem of double paper feeding. The paper feeding means of FIG. 2A uses a brush member 34 that contacts at least the front end of the paper stack 14. The paper feeding means of FIG. 2B has an air tube 36 in place of the brush member 34 for blowing air onto the front end of the recording paper stack 14.

FIG. 3A shows an example of a front view of the drum 6. The through hole 42 and the recess 48 are provided around the drum 6 along the axis of the drum in order to attract the front end of the recording paper. A notch 54 is also provided in the surface of the drum 6 along the axis of the drum to include the through hole 42.

The notch 54 is provided to protect the leading edge of the recording paper from air flow by positioning the leading edge of the recording paper slightly lower than the drum surface. This prevents the recording paper from coming off the drum due to airflow at high speeds.

In order to fix the rear end of the recording paper, a through hole 44 is provided in the recess 52 and a through hole 46 is provided in the recess 53 in parallel with the notch 54, respectively. The two parallel rows of through holes 44 and 46 allow recording paper of different sizes to be used. A large number of grooves 40 communicating with the recesses 48 are provided on the surface of the drum to allow the recording paper to be closely attached to the surface of the drum 6. Figures 3B and C are -
FIG. 4 is a cross-sectional view of the drum 6 along the line and - line. The leading edge of the recording paper is positioned above the notch 54.
A slope 56 on the drum surface across the notch 54 is provided to facilitate removal of the recording paper.

Figures 4A to 4C show the process of paper feeding. First, the pick 16 is dropped onto the recording paper stack 14 and attracts the uppermost recording paper (FIG. 4A). Next, the pick 16 is tilted about 30 degrees on the stack 14 (FIG. 4B). This action of folding the recording paper, together with the action of the brush member 34 or the air tube 36, helps ensure that only one recording paper is attracted to the pick 16. The paper is lifted from the paper stack 14 (FIG. 4C), completing the paper feeding operation. The operation of the pick 16 can be achieved, for example, by a pair of cams coupled to a camshaft, a motor rotating the cams, one end rotatably attached to the pivot shaft and the other end coupled to the pick 16, which rotates the pick 16 in response to rotation of the cams. is controlled by conventional means (not shown) in combination with a pair of arms for actuating.

Figures 5A to 5D show the process of loading the recording paper onto the drum. At the start of paper feeding, the drum 6 is rotated to an accurate initial position, and exhaust air inside the drum 6 has begun. When the recording paper is lifted and attracted to the mounting position of the notch portion 54 of the drum 6, the idler roller 12 rotates and presses the recording paper 60 against the drum surface (FIG. 5B). So pick 16
The evacuation operation of the drum 6 is stopped, and the drum 6 rotates once at a low speed to wind the recording paper 60 around the tension drum 6 while crossing the pick 16 (FIG. 5C). The only driving force required to mount the recording paper 60 on the drum 6 is the rotation of the drum itself. Idler roller 12 prevents recording paper 60 from sliding on the drum surface. The idler roller 12 then rotates back to its original position, completing the paper loading process (FIG. 5D). Thereafter, the rotational speed of the drum 16 is accelerated to the recording speed. idler roller 1
The operation of 2 is controlled by a lever 10 which rotates about a pivot shaft 8 driven by a motor driven cam or solenoid.

6A to 6C show the process of removing the recording paper from the drum 6. FIG. When recording is completed, the drum 6 is decelerated to a low speed (FIG. 6A), and the removal claw 26
and the idler roller 30 rotates to the drum surface. The removal claw 26 comes into contact with the drum surface (see FIG. 6B) at an inclined portion (see FIG. 3A) located between both ends of the recording paper. As the drum 6 continues to rotate, the front end of the recording paper 60 rides on the removal claw 26, and the recording paper 60 is discharged onto the output tray 22 (FIG. 6C). After the front end of the recording paper 60 is removed by the removal claw 26, the idler roller 30 presses the recording paper 60 against the drum 6 in order to move the recording paper 60 to the output tray 22 only by the rotational force of the drum itself. . Since the idler roller 30 is brought into contact with the margin of the recorded image on the recording paper 60, there is no risk that the recording paper will be smeared with ink.
The exhaust of the drum continues to hold the trailing edge of the recording paper until the entire recording paper is removed by the removal claw 26. Removal claw 26 and idler roller 30
The operation is performed by the pivot shaft 24 and lever 28.
(omitted from FIGS. 6A to 6C for simplicity) and driven by a conventional drive device.
Idler roller 30 may be removed if sufficient suction is provided to prevent paper 60 from sliding off the drum surface.

7A-7D show another paper feeding means 20' associated with the recording medium processing apparatus according to the present invention. This is similar to the sheet feeding means 20 shown in FIGS. 2A and 2B except for the following two points. That is, one point is that the double paper feeding prevention means 34 and 36 are replaced by an air pipe 64 having an air outlet located at the front end of the recording paper stack 14, and the operation of the pick 16 is changed.
In the pick operation, even if the pick 16 is located at the top of the recording paper stack 14 with the maximum number of sheets,
Even if it is located on the last recording paper, pick 1
The distance between the front end of the paper stack 6 and the recording paper stack 14 is kept constant. The suction force by the pick 16 alone is not sufficient to pull up the recording paper separated from the front end of the pick 16 to the pick 16. Air flow from air line 64 is provided to lift several sheets of paper and separate them from each other and from the rest of paper stack 14. When the pick 16 is dropped onto the stack while the top few picks are floating, the top pick 16 comes into contact with the entire suction surface of the pick 16 and is sucked. At this time, since the airflow separates the top few sheets, other recording sheets are not attracted to the pick 16. The pick 16 is then rotated to a position approximately 30 degrees from horizontal, and the subsequent operation is similar to that described above. According to this paper feeding means, double feeding can be effectively prevented. This is particularly suitable when porous recording paper is used.

FIGS. 8A to 8C show other paper feeding and mounting means related to the recording medium processing apparatus of the present invention. The air pipe 64 floats the recording paper up to the drum 6, and
This allows the sheet to be attracted to the notch 54 of the drum 6. When this adsorption occurs, the air pipe 64
The airflow is stopped and all the recording sheets except one, which was attracted to the notch 54 of the drum, are returned to the tray. Thereupon, the drum 6 is rotated and accelerated to the recording speed, and the recording paper is wound around the drum 6. The sides and rear of the recording paper tray (not shown) are raised high enough to hold the recording paper in position as the air space lifts the recording paper towards the drum 6. The relative position of paper stack 14 and drum 6 is relevant to the occurrence of double feeding. FIG. 8A shows a case in which the front end of the paper stack 14 is located on the drum center line 70 and double feeding is most likely to occur. FIG. 8B shows the case where the front end of paper stack 14 is located in front of centerline 70, making double feeding less likely than in the previous case. FIG. 8C shows the case where the front end of paper stack 14 is located behind centerline 70, which is the least likely to cause double feeding.

9A to 9C show the paper feeding and loading process of the configuration shown in FIG. 8C. First, the drum 6 is stopped at the mounting position. The air pipe 64 releases air and floats the uppermost several sheets toward the drum 6.
The sheet is ready to be sucked onto the drum 6 (No. 9A
figure). Next, the topmost sheet is attracted to the drum 6.
At this time, the recording paper stack 14 is aligned with the drum center line 7.
Since it is located after 0, the attracted recording paper is slightly curved relative to other recording papers (FIG. 9B).
The air flow from the air line 64 is then stopped and the other paper is returned onto the paper stack 14. As the top recording paper moves back down except for the front end held by the drum 6, the degree of curvature of the recording paper increases as shown in FIG. 9C. This final operation serves to separate the second recording sheet from the first recording sheet in the case of double lifting of the recording sheet.

FIG. 10 is a perspective view of still another paper feeding/loading means related to the recording medium processing apparatus of the present invention. Air line 64 is slightly modified to include a fluff box 78 and a solenoid actuated valve plate 76. Further, the guide 74 is connected to the paper feed and
It is added to the attachment means. Flatshua Box 7
8 has a ventilation hole 82 at the top and two small slits 84 at the front. The valve plate 76 is actuated back and forth over the vent 82 of the flattening box 78 such that the opening 80 corresponds to the vent 82 when the valve plate 76 is in the retracted position.
has. The recording paper pushing section 75 is constructed by bending the free end of the valve plate 76.

Next, the paper feeding and mounting process of the paper feeding and mounting means shown in FIG. 10 will be explained with reference to FIGS. 11A to 11F. First, the drum 6 is stopped at the mounting position. Valve plate 76 is in the retracted position and the discharged air flows directly out through vent 82 and opening 80 (FIG. 11A). Next, valve plate 7
6 is pushed forward and blocks the vent hole 82. Accordingly, air is released from the slit 84 in front of the flattening box 78, causing several sheets of recording paper to float toward the drum 6, and one of the upper sheets is attracted to the drum 6 (FIG. 11B). The recording paper extrusion section 75 has no function at this stage. After that, the valve
Plate 76 is returned to its original position and air again exits from the top of flattening box 78. In this way, all the recording sheets except one that was attracted to the drum 6 return to the recording sheet stack 14 (the 11th
Figure C). Thereupon, the drum 6 is rotated and accelerated to the recording speed, and the recording paper is loaded onto the drum 6. Even if double paper feeding occurs, when the drum 6 rotates, the second recording paper 88 falls due to the action of the guide 74 and is located just in front of the recording extrusion section 80 (the first
1D figure). As the loading cycle continues, solenoid 72 is again actuated and paper pusher 75 pushes excess paper back into paper stack 14 for recycling (FIG. 11E). The operation of floating the recording paper at this time does not interfere with the loading of the recording paper. This is because the installed recording paper is blocking the through hole of the drum 6, which weakens the air flow, and the solenoid is quickly turned off, making it impossible to levitate the recording paper on the paper stack 14. be. Finally, the valve plate 72 is returned to complete the loading of the recording paper (FIG. 11F). guide 74
now performs one action. That is, the trailing edge of the recording paper is brought sufficiently close to the drum 6 to open the through holes 44 and 46 for the trailing edge.
so that it is attracted to the drum 6.

Effects of the Invention According to the present invention, highly reliable automatic recording medium processing for drum-type recording devices is achieved. The moving path of the recording paper within the recording device is the shortest. That is, the recording paper on the recording paper stack is directly loaded onto the drum from the recording paper stack, and after recording is completed, it is sent directly from the drum to the output tray. In this way, since the recording paper conveyance device found in most conventional recording apparatuses is removed, paper jams can be prevented from occurring. Furthermore, the overall shape of the recording apparatus can be made smaller and costs can be reduced. The recording medium processing apparatus according to the present invention can use various recording media having different sizes, weights, surface conditions, etc. Furthermore, unlike conventional recording devices, there is no need to lift the stack of paper sheets to the paper feed means by means such as a spring, so differences in the weight of the paper stacks have no effect on the performance of the apparatus. Furthermore,
In the present invention, since a notch is provided on the surface of the drum along the axis of the drum, the front edge of the recording paper (sheet-like recording medium) can be positioned slightly lower than the drum surface, and the front edge of the recording paper can be kept in the air. Can be protected from flow. Therefore, it is possible to prevent the recording paper from coming off the drum due to airflow at high speeds.
Regarding a transparent film having a separation sheet, the separation sheet also passes through the same path as the transparent film. The transparent film and separation sheet can be optically distinguished by conventional means. Thus, the coated surface of the transparent film can be completely protected from damage since the transparent film has separation sheets sandwiched between them before and after recording. Furthermore, since the lifted recording paper is automatically placed in the correct position for loading, there is no need to detect the leading edge of the recording paper.

Although various preferred embodiments of the present invention have been described above, it will be obvious to those skilled in the art that many modifications and changes can be made without departing from the spirit of the invention.

[Brief explanation of drawings]

1 to 11F are all explanatory diagrams of the present invention, FIG. 1 is a simplified diagram showing a recording medium processing device, and FIGS. 2A and 2B are perspective views showing paper feeding means related to the recording medium processing device. Figures 3A to 3C are a side view and sectional view showing an example of the drum, and Figures 4A to C are
5A to D and 6A to C are simplified diagrams showing the process of feeding, loading, and removing a recording medium in the apparatus of FIG. 8A to C and 9A to C are simplified diagrams showing the process of operation of other paper feeding and mounting means, and FIG. 10 is a perspective view showing still another paper feeding and mounting means. 11A to 11F are simplified diagrams showing the paper feeding and mounting process by the means of FIG. 10. In the figure, 6 is a drum, 14 is a recording medium stack,
20, 20', 64, and 84 are paper feeding means, 42 is a through hole, 54 is a notch, and 60 is a recording medium.

Claims (1)

[Scope of Claims] 1. A recording medium processing device for a recording apparatus in which a sheet-shaped recording medium is mounted on a drum from a recording medium stack and removed from the drum after recording, wherein a shaft of the drum is attached to the surface of the drum. a notch provided along the notch portion of the drum; a vacuum pump means for evacuating the inside of the drum; a paper feeding means for feeding the recording medium to the notch portion of the drum, the front end of the recording medium is attracted to the through hole of the notch portion of the drum, and the entire recording medium is fed to the drum according to rotation of the drum. A recording medium processing device characterized in that it is adapted to be attracted to its surroundings. 2. The paper feeding means according to claim 1, wherein the paper feeding means includes a blowing means for blowing air to the front end of the recording medium stack to float the recording medium on the upper part of the stack toward the drum. Recording media processing device.