WO1997016316A1 - Appareil d'impression electrostatique en couleur - Google Patents
Appareil d'impression electrostatique en couleur Download PDFInfo
- Publication number
- WO1997016316A1 WO1997016316A1 PCT/JP1996/003163 JP9603163W WO9716316A1 WO 1997016316 A1 WO1997016316 A1 WO 1997016316A1 JP 9603163 W JP9603163 W JP 9603163W WO 9716316 A1 WO9716316 A1 WO 9716316A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- electrostatic recording
- electrostatic
- recording head
- recording medium
- pressing
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
- B41J2/385—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective supply of electric current or selective application of magnetism to a printing or impression-transfer material
- B41J2/41—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by selective supply of electric current or selective application of magnetism to a printing or impression-transfer material for electrostatic printing
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
- B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
- B41J11/00—Devices or arrangements of selective printing mechanisms, e.g. ink-jet printers or thermal printers, for supporting or handling copy material in sheet or web form
- B41J11/20—Platen adjustments for varying the strength of impression, for a varying number of papers, for wear or for alignment, or for print gap adjustment
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/01—Apparatus for electrographic processes using a charge pattern for producing multicoloured copies
- G03G15/0142—Structure of complete machines
Definitions
- the present invention provides a single-pass color image forming apparatus that forms an electrostatic latent image for each primary color on a recording surface of a recording medium such as paper 'film' with an electrostatic recording head and develops the electrostatic latent image with a liquid toner.
- the present invention relates to an electrostatic recording apparatus, and more particularly to a color electrostatic recording apparatus having a backrest mechanism for bringing a recording medium into sliding contact with an electrostatic recording head with an appropriate pressing pressure.
- the electrostatic recording device forms an electrostatic latent image on a recording medium such as paper 'film' cloth using an electrostatic recording head, and then develops the image by developing the electrostatic latent image with liquid toner. Record.
- a spacer made of silica particles having a diameter of several m is sprayed at an appropriate density, and the recording medium is pressed against the electrostatic recording head by a pad roller from the opposite side.
- the recording medium When a discharge is caused between the electrodes corresponding to the respective pixels of the electrostatic recording head in this state, the recording medium is charged based on the image information, and an electrostatic latent image is formed.
- the recording medium that has passed through the electrostatic recording head is coated with liquid toner in which toner particles have been diffused by a toner roller.
- the liquid toner When the liquid toner is applied to the recording medium, the toner particles charged to the opposite polarity to the electrostatic latent image are attracted to the electrostatic latent image formed on the recording medium by electrostatic force, and the surface layer of the recording medium is formed. And the electrostatic latent image is developed.
- the above-mentioned electrostatic recording heads are provided for each of the four primary colors of cyan, magenta, yellow, and black, and the above-described method can be performed by a single transfer of the recording medium. Record 4 colors and get a blank image.
- the pad roller rotates, and the recording medium always slides on the surface of the electrostatic recording head with a constant pressing pressure.
- a backrest Such a device that presses the recording medium against the electrostatic recording head with an elastic member facing the electrostatic recording head with the recording medium interposed therebetween is generally called a backrest.
- FIGS. 4A and 4B are cross-sectional views schematically showing a backrest portion using the pad roller 12.
- the electrostatic recording head 11 has a large number of electrodes for forming an electrostatic latent image in the main scanning direction (perpendicular to the paper surface).
- Auxiliary electrodes 14a and 14b are respectively buried in a straight line.
- the cross-sectional shape of the electrostatic recording head 11 is an arc that is upwardly convex.
- the distance between the main electrodes is about 0.2 mm, and the distance between the capture electrodes is about 3 thighs.
- the recording medium 10 is pressed downward by a pad roller 12 serving as a backrest, and is conveyed in the direction of the arrow while maintaining a state where the recording surface is in sliding contact with the surface of the electrostatic recording head 11.
- the recording medium 10 is driven by the take-up force of the take-up roller disposed at the most downstream while maintaining the state in which the recording medium 10 is kept in sliding contact with the head surface by the pad roller 12 serving as a backrest. It is transported in the scanning direction (the direction of the arrow). At this time, back tension is applied to the recording medium in the opposite direction.
- the deformation due to the pressing of the pad roller is exaggerated, but the pad roller is formed by winding high quality rubber on the surface of a metal mandrel. Considerably smaller than the ones.
- the width of the contact between the pad roller and the electrostatic recording head is about several millimeters because the electrostatic recording head itself is also convexly curved.
- the dashed lines shown in Figs. 4 (a) and (b) indicate the recording head at each position on the recording head. It is a curve which shows what the force which presses a recording medium is.
- the pressing pressure applied to the recording medium peaks at the center of the head where the deformation of the pad roller is large, and decreases as the distance from the head increases.
- the peak position of the pressing pressure also changes, as shown in FIG. Therefore, when the recording medium is pressed against the electrostatic recording head by the pad roller, not only the pressing pressure but also the installation position is important.
- the optimal pressing pressure for recording varies depending on the material and thickness of the recording medium, the electrical properties of the dielectric layer, the condition of the spacers spread on the surface, and the like. It varies greatly depending on the type of recording medium.
- the pressure on the head surface of the recording medium depends on the magnitude of the tension applied to the recording medium in the transport direction when the pressing force of the backrest from behind is constant. That is, the tension applied to the recording medium is parallel to the tangential direction of the electrostatic recording head 11, and the vertically downward component of this tension contributes to the pressure on the head surface of the recording medium. Therefore, the higher the tension applied to the recording medium, the higher the pressure on the head surface, and the lower the tension applied to the recording medium, the lower the pressure on the head surface.
- the recording surface of the recording medium is applied to the head surface with an appropriate pressure. It is important to make sliding contact. In other words, if the pressure of the recording medium is insufficient, a phenomenon in which the image to be recorded is interrupted halfway will occur, while if the pressure is excessive, the image will be recorded in a part that should not be printed. Spurious A phenomenon called lighting occurs.
- the recording medium slides in contact with the surface of each electrostatic recording head provided in the number of primary colors in series, and slides with each electrostatic recording head.
- the frictional force that is applied to the recording medium in the contact direction and is parallel to the transport direction at the time of contact makes the resistance against the winding force of the winding roller.
- the recording medium on which the liquid toner is applied and developed has a force for sucking and removing the remaining excess liquid toner by a suction device before reaching the next electrostatic recording head. Resistance occurs to the winding force of the take-up roller.
- the single-pass type color electrostatic recording apparatus includes many elements that generate resistance to the winding force during the conveyance of the recording medium. Therefore, the tension applied to the recording medium is small at the upstream and downstream. The bigger you go. Therefore, the pressure on the head surface of the recording medium is small at the upstream side and large at the downstream side, so that a color image recorded on the upstream side is liable to drop, and a color image recorded on the downstream side is not.
- the present invention has been made in view of the above-described problems of the related art, and can easily adjust a pressing pressure of a recording medium that slides on an electrostatic recording head in accordance with a type of the recording medium. It is an object of the present invention to provide a color electrostatic recording device having a backrest mechanism.
- Another object of the present invention is to provide a color electrostatic recording apparatus in which an image of each color is appropriately recorded in a single-pass system.
- a color electrostatic recording apparatus is provided with a recording head which forms a latent electrostatic image when a recording medium is slid and conveyed, and is provided in a pair with the electrostatic recording head.
- the sliding contact adjusting means is provided by each having a different radius of curvature of the surface of the electrostatic recording head, and adjusting the pressing force J at the center of the electrostatic recording head. Is characterized by the fact that I have.
- a plurality of sets of electrostatic recording heads and developing means are arranged in series, and a single pass is obtained by forming and developing an electrostatic latent image of each color in each pair and finally obtaining a color image. It is characterized in that it is a system.
- the radius of curvature of the surface of the electrostatic recording head is such that the radius of curvature of the electrostatic recording head on the downstream side in the moving direction of the recording medium is larger than that on the upstream side.
- the sliding contact adjusting means includes pressing means for pressing the recording medium against the surface of the electrostatic recording head, and pressing pressure adjusting means for changing the pressing pressure at the center of the electrostatic recording head by the pressing means. And a backrest mechanism having the same. Further, a plurality of sets of the electrostatic recording head and the developing means are grouped in the moving direction of the recording medium, and the radius of curvature of the electrostatic recording head in the group on the downstream side of the upstream side is increased. It is characterized by having done.
- a color electrostatic recording apparatus uses a load to transfer a recording medium to an electrostatic recording head so that a recording surface of the recording medium conveyed slides against the electrostatic recording head.
- Pressing means for pressing against the surface of the head, supporting the pressing means from both sides in the longitudinal direction of the electrostatic recording head, and moving the pressing means vertically while maintaining the horizontal, so that the pressing means
- a pressing pressure adjusting means for changing a pressing pressure at a central portion of the electrostatic recording head when the recording medium is pressed against the surface of the electrostatic recording head.
- the pressing pressure adjusting means includes a sliding means for moving the pressing means in the front-rear direction of the electrostatic recording head to change a load of the pressing means at a central portion of the electrostatic recording head. It is characterized by the following.
- the pressing pressure adjusting means is previously stretched to have a predetermined tension, and the urging means for supporting a part of the load of the pressing means by the predetermined tension when the pressing means is suspended. It is characterized by having.
- the pressing pressure adjusting means includes a first member provided substantially horizontally supporting the pressing means from both sides, and a second member swingably connected to the first member at a substantially right angle. And the second member are swingably connected at a substantially right angle to the second member, are disposed substantially parallel to the first member, and constitute a substantially U-shaped assembly together with the first and second members.
- a third member a pin means for swingably connecting the second member and the third member, and a swing means for swingably supporting the assembly to the main body of the electrostatic recording apparatus;
- An urging means stretched in a state in which a tension in a direction of bringing the two members closer to each other is generated in advance, and first and second urging means in a range where the tension of the urging means is considered to be substantially constant.
- Relative movement restricting means for restricting relative movement between the first member and the third member so that the distance between the distal ends of the three members falls within a predetermined range; and the first member is located before and after the electrostatic recording head.
- a first driving means for rotating the second member about the pin means so as to slide in the direction, and a biasing means for the third member are stretched about the pin means.
- Second driving means for pivoting the part to be lifted in a direction to move upward It is characterized by the following.
- control means stores control information of the first drive means and the second drive means, and reads out this information as needed to read the slide position of the first member and the third member. And a control means for automatically setting the swing position.
- An information reading means for reading information on an appropriate pressing pressure of the recording medium recorded on the recording medium; and a sliding position of the first member and a third member based on the information read by the information reading means.
- Control means for automatically setting the vertical position is provided.
- the pressing means comprises a pad roller which rotates with the conveyance of the recording medium in sliding contact with the electrostatic recording head.
- the load on the electrostatic recording head of the pressing unit can be changed by moving the pressing unit up and down by the pressing pressure adjusting unit.
- the pressure at the time of sliding contact with the recording head can be set to an appropriate value, a desired electrostatic latent image is reliably formed, and image noise such as dropout and spurious lighting can be effectively suppressed.
- the sliding means moves the pressing means in the front-rear direction of the electrostatic recording head to change the load of the pressing means at the center of the electrostatic recording head. Even if the same load is applied to the entire head, this sliding motion
- the load at the center of the electrostatic recording head can be changed by adjusting the position of the pressing means in the front-rear direction. It can be a value.
- the first member and the second member are movably connected to each other at a substantially right angle, so that the second member is centered on the pin means by the first driving means. By rotating, the first member can be slid in the front-rear direction of the electrostatic recording head.
- first, second, and third members are swingably connected to each other to form a substantially U-shaped assembly, and a biasing means is provided between the first and third members so that the first and second members are connected to each other.
- a tension force is applied in advance in a direction in which the first and third members approach each other, and a relative movement range in a direction in which both the first and third members approach each other is limited to a predetermined range.
- the tension given to the urging means in advance is applied to the first and third members, so that the load on the head of the pressing means is such that the entire weight of the pressing means is applied, A state is obtained in which a load is obtained by subtracting the weight corresponding to the tension of the urging means from the weight of the means, and a state in which the weight of the pressing means is not applied at all.
- the pressure can be adjusted to an appropriate pressing pressure only by reading this information, thereby reducing the burden on the operator.
- the pressing pressure recorded as a barcode on the recording medium is read by means of information reading means such as a bar code reader, and the pressing pressure can be automatically adjusted, reducing the burden on the operator. Work efficiency is improved.
- the pad roller also rotates with the conveyance of the recording medium, so that the recording medium does not rub against the pressing means, and the life of the pressing means is extended, and A suitable pressing action can always be exerted on the recording medium.
- the electrostatic recording head and the developing means are arranged in series as many as necessary for color image recording, and the recording media are respectively statically arranged.
- An electrostatic latent image is formed by being conveyed so as to be in sliding contact with the electrographic head, and is then developed by the developing means by the electrostatic recording head of each color and the developing means.
- the electrostatic recording head and the developing means are divided into a plurality of groups, and the radius of curvature of the electrostatic recording head in the group located downstream is determined. It is characterized in that the radius of curvature is larger than the radius of curvature of the electrostatic recording head of the group located on the upstream side.
- the upstream group and the downstream group include one or more electrostatic recording heads and a developing unit.
- electrostatic recording heads and four developing means are provided, respectively, and these are arranged in two groups of the electrostatic recording head and the developing means located on the upstream side and two groups located on the downstream side. It is divided into two groups, namely, the electrostatic recording head and the developing means.
- the two surfaces have the same radius of curvature and the electrostatic recording head belonging to the downstream group.
- the radius of curvature of the surface of the head is larger than the radius of curvature of the surface of the electrostatic recording head belonging to the upstream group.
- the radius of curvature of the surface is increased toward the downstream electrostatic recording head.
- the pressure on the head surface tends to increase on the downstream side where the tension is large.
- the component that contributes to the pressure on the recording medium head surface is the vertically downward component, but the downstream electrostatic recording head
- the radius of curvature of the surface of the surface By increasing the radius of curvature of the surface of the surface, the ratio of the vertically downward component to the magnitude of the tension is reduced. Can be frustrated. Therefore, by making the radius of curvature of the downstream surface larger than that of the upstream surface, an increase in pressure on the head surface of the recording medium in the downstream electrostatic recording head can be suppressed.
- a group of two electrostatic recording heads on the upstream side and a group of two electrostatic recording heads on the downstream side Dividing into two electrostatic recording head groups, the radius of curvature of the surface of the two electrostatic recording heads included in the downstream group is reduced to the two electrostatic recording heads included in the upstream group. If the radius of curvature is larger than the radius of curvature of the surface of the head, the change in recording pressure in the four electrostatic recording heads can be suppressed within a certain range, and the door-to-door spurious lighting can be effectively prevented.
- FIG. 1 is a schematic sectional view of a portion for performing image recording for one color in a single-pass type color electrostatic recording apparatus according to an embodiment of the present invention
- FIG. 2 is an image recording portion as shown in FIG. 3 is a schematic perspective view of a backrest mechanism for adjusting the pressing pressure of the pad roller against the electrostatic recording head in FIG. 3.
- FIG. 3 shows the extension of the spring in the backrest mechanism in FIG. 2 along the X-axis (horizontal axis).
- Fig. 4 (a) and (b) are schematic cross-sectional views of the backrest using a pad roller
- Fig. 5 is the color diagram of the spring with its tension taken along the y-axis (vertical axis).
- FIG. 1 is a schematic sectional view of a portion for performing image recording for one color in a single-pass type color electrostatic recording apparatus according to an embodiment of the present invention
- FIG. 2 is an image recording portion as shown in FIG. 3 is a schematic perspective view of a backrest mechanism
- FIGS. 6 (a) and (b) are schematic cross-sectional views of a portion for performing image recording for each of the four primary colors in the electrostatic recording device, and FIGS. 6 (a) and (b) show the tension of the recording medium and the head in each electrostatic recording head. Is a graph showing a change in pressure of the recording medium with respect to the surface of a) If the radius of curvature of the surface of the electrostatic recording head is equal, a graph when the (b) is larger the radius of curvature of the head to the electrostatic recording on the downstream side.
- FIG. 1 is a cross-sectional view schematically showing a portion for recording an image of one color in a single-pass type color electrostatic recording apparatus.
- a recording medium 10 on which an image is formed is conveyed in a direction indicated by arrows a and (sub-scanning direction) in a state where a back tension is applied.
- the electrostatic recording head 11 forms an electrostatic latent image on the lower surface of the recording medium 10 conveyed while being slid thereon, and is supplied from a predetermined signal processing circuit. Driven based on the image signal.
- a pad roller 12 which is a part of a backrest mechanism described later, presses the recording medium 10 toward the electrostatic recording head 11, and presses the recording medium at an appropriate pressure. Sliding contact with the electrode part of 1.
- a spacer made of silica particles having a diameter of about 5 to 30 m is sprayed at an appropriate density. The spacer forms a discharge gap between the electrostatic recording head and the dielectric layer of the recording medium. The recording medium is charged by the discharge between the recording medium and the electrostatic recording head, and the electrostatic gap is generated. A latent image is formed.
- the recording medium 10 that has passed through the electrostatic recording head 11 is sent to the developing unit 20.
- the developing unit 20 includes idle rollers 26, 2 for slidingly contacting the recording medium 10 with the toner roller 21, the scraper 22, and the guide bars 24, 25 of the suction unit 23 with an appropriate pressure. 7, 28 force ⁇ Provided above the recording medium 10.
- the scraper 22, the guide bars 24, 25, and the support member 32 for the guide bar are detachably fixed to the case member 29 including the toner roller 21 by a fixing member (not shown). It has been done.
- a single-pass type color electrostatic recording apparatus such an electrostatic recording head and a current image section are provided, for example, in four stages in series, and a primary image is finally recorded in each stage, whereby a color image is finally obtained.
- the toner supply tray 30 located below the toner roller 21 is filled with liquid toner 31 with a toner particle dispersed in a predetermined solvent ⁇ 31, to a level slightly exceeding the lower end of the toner roller 21. Have been.
- the liquid toner is sent from the toner bottle to the toner supply tray 30 by a pump via a predetermined path (not shown).
- the toner particles in the liquid toner are charged to the opposite polarity of the electrostatic latent image.
- the toner roller 21 rotates in the counterclockwise direction, the liquid toner 31 is lifted up by the groove on the surface of the toner roller 21, and the toner roller 21 contacts the recording medium 10 at the portion where the toner roller 21 contacts the recording medium 10. It is applied to the lower surface.
- the toner particles of the liquid toner adhered to the portion where the electrostatic latent image is formed are attracted to the electrostatic latent image formed on the recording medium by electrostatic force, and the surface of the recording medium where the electrostatic latent image is formed is formed.
- the electrostatic latent image is developed. After recording an image of one color, if another color is recorded at the next stage while the solvent of the liquid toner remains on the recording medium 10, the image quality will be degraded. For this reason, the toner remaining on the recording medium is removed after the development, and is further performed by a blower device provided downstream of the developing section. And dry the solvent.
- a scraper 22 and a suction unit 23 are provided downstream of the toner roller 21 in order to remove most of the unnecessary liquid toner before drying with a blower device.
- the scraper 22 is made of a stainless steel rod-like member that is slightly longer than the width of the recording medium 10 and has a circular cross section with a diameter of about 5 mm.
- the axis of the scraper 22 is fixed to the case member 29 so as to be orthogonal to the traveling direction of the recording medium.
- the scraper 22 removes most of the unnecessary liquid toner remaining on the recording medium as the recording medium 10 slides thereon. ⁇ can fallen liquid toner is dropped along the inner wall of the case member as indicated by the arrow a 2.
- the suction section 23 is made to have a negative pressure in the space between the guide bars 24 and 25 on the lower side of the recording medium 10 by a pump (not shown) connected via the suction path 33. Sucks the liquid toner remaining on the recording medium.
- FIG. 2 is a schematic perspective view of a backrest mechanism that supports the pad roller 12 shown in FIG. 1 and adjusts a pressing pressure against the surface of the electrostatic recording head 11.
- FIG. 2 shows only one backrest mechanism, a similar mechanism that is symmetrical to the backrest mechanism is also provided on the opposite side of the electrostatic recording device. Supports 1 2 axis 1 2 a.
- the backrest mechanism 40 is movably held by a side wall member 41 of the electrostatic recording device main body by a pin 41a.
- the backrest mechanism 40 has brackets 50, 51, and 52.
- the bracket 50 and the bracket 51 swing by the pin 41a, and the bracket 51 and the bracket 52 by the pin 43. It is movably connected, and the bracket 52 is slidable in the front-to-back direction (the direction of the arrow).
- the sliding distance is about 3 to 4 times.
- the metal fittings 50, 51, and 52 have a U-shaped cross section to increase the strength.
- Metal fitting 50 is in metal fitting 51
- metal fitting 51 is in metal fitting 52.
- the rotation shaft 12a of the pad roller 12 penetrates an opening 52b provided on the side surface of the metal fitting 52, and a ball bearing is provided at an opening 52c provided on the other side surface. (Not shown) It is rotatably supported.
- the output shaft 60 a inserted into the elongated hole 51 a provided in the metal fitting 51 is fixed at a position eccentric from the rotation shaft of the stepping motor 60 fixed to the side wall member 41.
- the output shaft 60a rotates the bracket 51 around the pin 41a, and simultaneously slides the bracket 52 connected to the bracket 51 in the front-rear direction.
- the range in which the metal fitting 50 and the metal fitting 52 can relatively move in the vertical direction is restricted by the metal fitting 51 on the one hand, and the bent part 50 a provided at the tip of the metal fitting 50 on the other hand, and this bent part It is regulated by the notch 52a at the tip of the bracket 52 into which 51a is inserted.
- the metal fitting 50 and the metal fitting 52 are closest to each other when the bent portion 50a is in contact with the lower end of the cutout 52a, and are most separated when it is in contact with the upper end.
- the slidable range of the metal fitting 50 and the metal fitting 52 in the front-rear direction is also limited by the bent part 50a and the notch part 52a.
- the panel 70 between the tip of the metal fitting 50 and the tip of the metal fitting 52 has a tension force that tries to bring the metal fittings 50 and 52 closer together when stretched as shown in the figure.
- a tension force that tries to bring the metal fittings 50 and 52 closer together when stretched as shown in the figure.
- a panel with constants and dimensions that are about one-fourth of the weight. That is, a tension equivalent to about one-fourth of the total weight of the pad roller 12 is applied to the spring 70 in advance.
- pretension is applied to the spring 70 in advance. Therefore, together with the other spring on the opposite side, the bracket 50 and the bracket 52 are urged with a tension of about half the weight of the pad roller.
- FIG. 3 is a characteristic diagram of the spring 70 with the extension of the panel 70 on the X axis (horizontal axis) and the tension of the panel 70 on the y axis (vertical axis).
- the inclination of the straight line in this figure is the panel constant of the spring 70.
- the panel 70 is stretched by a predetermined length in advance and stretched between the tip of the metal fitting 50 and the tip of the metal fitting 52 to be given a pretension force.
- the relative movement of the metal fitting 50 and the metal fitting 52 is indicated by X in FIG. 3 by the bent part 50a and the notch part 52a. It is limited to the narrow range shown by. Therefore, within this relative movement range, the tension caused by the spring 70 is equal to the tension T applied as pretension, and can be regarded as a substantially constant value.
- Openings 50 b and 50 c provided on both sides of the metal fitting 50 are provided with side wall members of the main body. Pin 41b fixed to 41 is inserted. The pin 41 b and the openings 50 b and 50 c regulate the entire movable range of the backrest mechanism 40 centered on the pin 41 a.
- another stepping motor 80 is fixed to the side wall member 41 of the main body.
- the stepping motor 80 is provided with an output shaft 80a that is parallel and eccentric to the rotation axis.
- the eccentric output shaft 80a of the stepping motor 80 is inserted into a rectangular opening 50d provided in the bracket 50.
- the output shaft 80a is not in contact with the upper end or the lower end of the opening 50d, the bent portion 50a is in contact with the lower end of the cutout 52a, and the entire backrest mechanism 40 is a pin 4 It can swing about 1a as a center axis, so that the entire weight of the pad roller is added on an electrostatic recording head (not shown) below the pad roller.
- the stepping motor 80 rotates and the output shaft 80a comes into contact with the upper end of the opening 50d and the bracket 50 is lifted in a cantilevered state centered on the pin 41a, the bent portion 50a Is suspended between the lower end and the upper end of the cutout 52a.
- the above-mentioned pretension is applied to the spring 70, and the tension becomes the above-mentioned predetermined constant value. Is loaded with a load equivalent to about one-half of the total weight of the pad roller. Also, at this time, the spring
- the pressing pressure of the pad roller 12 against the electrostatic recording head is determined correspondingly. Moreover, it is necessary to select one of the three types of load conditions of Pad Roller 1 and 2.
- the sliding position of the bracket 52 By adjusting the sliding position of the bracket 52, the pressing pressure of the recording medium at the central portion of the electrostatic recording head can be continuously adjusted over a wide range. Therefore, by adjusting the load state of the pad roller 12 and the sliding position of the bracket 52 so that the pressing pressure of the pad roller is appropriate, image noise such as drop-out and sliding can be effectively prevented. .
- the present invention is not limited to the above embodiment, and various changes can be made within the scope of the gist.
- the appropriate pressing pressure on the electrostatic recording head differs depending on the type of recording medium, and if the appropriate pressing pressure is known in advance for a plurality of recording media to be used, the corresponding pad roller can be used. Since the load condition of (1) and the slide position of the bracket (52) can be set, in order to reduce the burden on the operator, an appropriate pressing pressure of the recording medium is applied to the recording medium with a bar code, for example, somewhere on the recording medium.
- the information about the load is read by a bar code reader, the stepping motors 60 and 80 are controlled by the control means, and the load state of the pad roller 12 and the sliding position of the bracket 52 are automatically recorded. You may make it set. Also, this information is stored in a memory, and this information is read out as necessary.
- the stepping motors 60 and 80 are controlled by a control means, and the load state of the pad roller 12 and the sliding position of the bracket 52 are controlled. Can also be set automatically.
- the pressure applied to the head by the pressing means can be adjusted, and the pressure applied to the recording medium slidably in contact with the head can be set to an appropriate value.
- An electrostatic latent image is reliably formed, and image noise such as dropout / spurious lighting can be effectively suppressed.
- the pressing pressure of the pressing means is variable under a high degree of freedom, so that drop-to-spurious lighting is effective.
- An electrostatic recording device that can select an appropriate pressing pressure that can prevent the image from being printed, improves the image quality of the printed image, and enables appropriate image recording flexibly on various recording media with different properties.
- the backrest mechanism can be provided.
- the recording medium 10 when recording for one color, is composed of an electrostatic recording head 11, a backrest 12, a toner holder 21, And And idle rollers 26, 27, and 28, and receives a downward suction force at suction section 23. Since these resistances to the winding force of the recording medium, the tension of the recording medium after exiting the suction unit 23 becomes larger than the tension of the recording medium before entering the recording head 11. .
- FIG. 5 is a cross-sectional view schematically showing a portion where image recording is performed for each of the four primary colors of cyan, magenta, yellow, and black.
- the suction unit 23 is provided in four stages in series.
- the recording medium 10 is conveyed in the downstream direction by the tension in the direction of the arrow larger than this based on the winding force, with the back tension force being applied. While the recording medium is being conveyed, the electrostatic recording heads 11a to 11d, the toner rollers 21a to 21d, the suction units 23a to 23d, and the recording medium are sent to these devices from above. It comes into sliding contact with many pad rollers that press 10.
- the present inventor has paid attention to the fact that, when the lengths of the portions in contact with the recording medium are equal, the vertically downward component of the tangential force on the head surface depends on the radius of curvature of the head surface. . That is, if the radius of curvature of the head surface is large, the vertically downward component is small, and therefore the pressure of the recording medium 10 on the head surface is small. Conversely, if the radius of curvature of the head surface is small, the vertical downward component is large, and the pressure of the recording medium 10 on the head surface is large. Therefore, even if the tension is large as in the downstream side, the pressure on the head surface of the recording medium can be reduced if the vertical downward component is small. Therefore, in the present embodiment, as shown in FIG.
- Figures 6 (a) and (b) show the tension of the recording medium at each electrostatic recording head (open display, unit kg) and the pressure of the recording medium against the head surface (black display, unit kg / mm).
- (A) is a graph showing the changes in the radii of curvature of the four electrostatic recording heads. Assuming 23.5 ran, (b) shows that the radius of curvature of the surface of the two upstream electrostatic recording heads 11a and 11b is 23.5, as shown in FIG. and jobs, a case where the radius of curvature of the downstream side of the two electrostatic recording the head 1 1 c and 1 1 d the surface of the 6 5 mm c Note, T.
- the plot at represents the magnitude of the tension of the recording medium before reaching the recording section, and the plot at ⁇ , ,, , 2 , , 3 , indicates the electrostatic recording heads 11a, lib, lie, measured the tension of the recording medium and the pressure on the head surface at 11 d.
- the present invention is not limited to the above embodiment, and various changes can be made within the scope of the gist.
- two electrostatic recording heads on the upstream side and two electrostatic recording heads on the downstream side are used. Have the same radius of curvature, but the radius of curvature of the head surface may be gradually increased from upstream to downstream.
- the surface of the downstream one has a larger radius of curvature than that of the upstream side, thereby allowing the recording head to be in sliding contact with the head. An increase in pressure on the head surface of the electrostatic recording head downstream of the medium can be suppressed.
- the change in pressure during recording in each electrostatic recording head can be substantially constant, or the change can be kept within a predetermined range, thus enabling drop spurious lighting.
- This can provide a color electrostatic recording device that can prevent the color electrostatic recording device.
- the force recording apparatus of the present invention has a backrest mechanism for slidingly contacting a recording medium with an electrostatic recording head with an appropriate pressing pressure, and records the radius of curvature of the surface of the electrostatic recording head. The size is increased on the downstream side of the medium.
- This color electrostatic recording apparatus is a single-pass type apparatus having a plurality of electrostatic recording sections, and a single image can be obtained on a recording medium by passing through the last electrostatic recording section.
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019980703139A KR19990067188A (ko) | 1995-10-30 | 1996-10-29 | 컬러 정전 기록기 |
AU73381/96A AU7338196A (en) | 1995-10-30 | 1996-10-29 | Color electrostatic recording apparatus |
BR9611380A BR9611380A (pt) | 1995-10-30 | 1996-10-29 | Registrador eletrostático a cores |
EP96935485A EP0876919A4 (en) | 1995-10-30 | 1996-10-29 | ELECTROSTATIC INK PRINTING MACHINE |
US09/065,049 US6160564A (en) | 1995-10-30 | 1996-10-29 | Color electrostatic recorder with adjustable pressure on a recording medium |
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP7/281844 | 1995-10-30 | ||
JP7/281843 | 1995-10-30 | ||
JP28184495A JP3501571B2 (ja) | 1995-10-30 | 1995-10-30 | カラー静電記録装置 |
JP28184395A JPH09127802A (ja) | 1995-10-30 | 1995-10-30 | 静電記録装置のバックレスト機構 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1997016316A1 true WO1997016316A1 (fr) | 1997-05-09 |
Family
ID=26554362
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP1996/003163 WO1997016316A1 (fr) | 1995-10-30 | 1996-10-29 | Appareil d'impression electrostatique en couleur |
Country Status (7)
Country | Link |
---|---|
US (1) | US6160564A (ja) |
EP (1) | EP0876919A4 (ja) |
KR (1) | KR19990067188A (ja) |
CN (1) | CN1080647C (ja) |
AU (1) | AU7338196A (ja) |
BR (1) | BR9611380A (ja) |
WO (1) | WO1997016316A1 (ja) |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0235452A (ja) * | 1988-07-26 | 1990-02-06 | Seiko Instr Inc | 画像記録装置 |
JPH06167860A (ja) * | 1992-11-30 | 1994-06-14 | Ricoh Co Ltd | 画像形成装置 |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS59155871A (ja) * | 1983-02-25 | 1984-09-05 | Canon Inc | 画像形成装置 |
JPS6167860A (ja) * | 1984-09-11 | 1986-04-08 | Nitto Electric Ind Co Ltd | 剥離現像装置 |
CA1295881C (en) * | 1985-04-12 | 1992-02-18 | Peter Kamas | Single-pass color plotter |
JPH0235452U (ja) * | 1988-08-29 | 1990-03-07 | ||
JP2612058B2 (ja) * | 1988-12-23 | 1997-05-21 | キヤノン株式会社 | 熱記録装置 |
US5063398A (en) * | 1990-03-06 | 1991-11-05 | Matsushita Graphic Communication Systems, Inc. | Color image recording apparatus |
JPH06202430A (ja) * | 1992-12-28 | 1994-07-22 | Canon Inc | 画像形成装置 |
EP0818715B1 (en) * | 1993-03-05 | 2001-07-18 | Kabushiki Kaisha Toshiba | Image Forming Apparatus |
US5745142A (en) * | 1994-12-14 | 1998-04-28 | Eastman Kodak Company | Apparatus for positioning a linear printhead in an accurate position with respect to a belt or web member |
-
1996
- 1996-10-29 WO PCT/JP1996/003163 patent/WO1997016316A1/ja not_active Application Discontinuation
- 1996-10-29 KR KR1019980703139A patent/KR19990067188A/ko active IP Right Grant
- 1996-10-29 CN CN96198002A patent/CN1080647C/zh not_active Expired - Fee Related
- 1996-10-29 BR BR9611380A patent/BR9611380A/pt not_active IP Right Cessation
- 1996-10-29 EP EP96935485A patent/EP0876919A4/en not_active Withdrawn
- 1996-10-29 US US09/065,049 patent/US6160564A/en not_active Expired - Fee Related
- 1996-10-29 AU AU73381/96A patent/AU7338196A/en not_active Abandoned
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0235452A (ja) * | 1988-07-26 | 1990-02-06 | Seiko Instr Inc | 画像記録装置 |
JPH06167860A (ja) * | 1992-11-30 | 1994-06-14 | Ricoh Co Ltd | 画像形成装置 |
Non-Patent Citations (1)
Title |
---|
See also references of EP0876919A4 * |
Also Published As
Publication number | Publication date |
---|---|
CN1201423A (zh) | 1998-12-09 |
US6160564A (en) | 2000-12-12 |
EP0876919A1 (en) | 1998-11-11 |
CN1080647C (zh) | 2002-03-13 |
KR19990067188A (ko) | 1999-08-16 |
EP0876919A4 (en) | 1999-05-12 |
BR9611380A (pt) | 1999-03-02 |
AU7338196A (en) | 1997-05-22 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6633733B2 (en) | Method and apparatus for printing an appropriate image even on a special recording medium | |
US6695504B2 (en) | Conveying apparatus and recording apparatus | |
US7302211B2 (en) | Charging apparatus and image forming apparatus with plated electrode | |
US5890822A (en) | Image forming apparatus | |
US6606945B1 (en) | Continuous medium printing apparatus | |
US6004052A (en) | Printing device with a heater provided at a charge applying station | |
JPH10507010A (ja) | 帯状記録媒体の表面及び裏面をプリントするプリンタ装置 | |
WO1997016316A1 (fr) | Appareil d'impression electrostatique en couleur | |
JP3381586B2 (ja) | 転写装置 | |
JPH09127802A (ja) | 静電記録装置のバックレスト機構 | |
JPH10240026A (ja) | 画像形成装置 | |
JP3151661B2 (ja) | 板状媒体の印刷装置 | |
JPH05323772A (ja) | 画像形成装置の帯電装置 | |
JP3501571B2 (ja) | カラー静電記録装置 | |
JP2002296972A (ja) | ベルト搬送装置 | |
US6128457A (en) | Squeeze roller elevating apparatus of a liquid developing apparatus | |
JPH10324037A (ja) | 板状媒体の印刷装置 | |
JP2002284383A (ja) | 記録媒体搬送装置及び記録装置 | |
JPH0753074A (ja) | 画像記録装置 | |
JP4157155B2 (ja) | 電子写真プリンタ | |
JPH0493971A (ja) | 定着装置 | |
JP2011215585A (ja) | 定着装置およびそれを用いた画像形成装置 | |
JPH10186895A (ja) | 画像形成装置 | |
JPH10161440A (ja) | 転写ベルト装置 | |
JPS6078763A (ja) | 静電記録体の空隙保持装置 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 96198002.8 Country of ref document: CN |
|
AK | Designated states |
Kind code of ref document: A1 Designated state(s): AL AM AU AZ BA BB BG BR BY CA CN CU CZ EE GE HU IL IS KE KG KR KZ LC LK LR LS LT LV MD MG MK MN MW MX NO NZ PL RO RU SD SG SI SK TJ TM TR TT UA UG US UZ VN AM AZ BY KG KZ MD RU TJ TM |
|
AL | Designated countries for regional patents |
Kind code of ref document: A1 Designated state(s): KE LS MW SD SZ UG AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG |
|
DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
121 | Ep: the epo has been informed by wipo that ep was designated in this application | ||
WWE | Wipo information: entry into national phase |
Ref document number: 09065049 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1019980703139 Country of ref document: KR |
|
WWE | Wipo information: entry into national phase |
Ref document number: 1996935485 Country of ref document: EP |
|
WWP | Wipo information: published in national office |
Ref document number: 1996935485 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: CA |
|
WWP | Wipo information: published in national office |
Ref document number: 1019980703139 Country of ref document: KR |
|
WWG | Wipo information: grant in national office |
Ref document number: 1019980703139 Country of ref document: KR |
|
WWW | Wipo information: withdrawn in national office |
Ref document number: 1996935485 Country of ref document: EP |