JP2005173430A - Unit attaching/detaching mechanism and printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the burden on a worker as much as possible when pulling out a photosensitive unit or a development unit from a housing. <P>SOLUTION: The photosensitive unit including a photosensitive rotating material having a latent image formed thereon and the development unit for developing the latent image, of which the clearance determination means for determining a clearance between the photosensitive rotating material and itself is brought into contact with the photosensitive rotating material are supported in the housing. In order to pull out the photosensitive unit and the development unit from the housing along an axial direction of the photosensitive rotating material, a unit moving means is provided which relatively moves the photosensitive unit and the development unit in the housing so as to separate the photosensitive rotating material and the clearance determination means from each other. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention provides a unit attaching / detaching mechanism for pulling out a photosensitive unit including a photosensitive rotator on which a latent image is formed and a developing unit for developing the latent image, which are supported inside the housing, and for drawing out the latent image from the inside of the housing. The present invention relates to a printer provided with the mechanism.

A photosensitive member on the surface of the photosensitive drum is exposed to form a latent image, toner is attached to the latent image and developed, the toner image is transferred to a recording sheet, and the transferred toner image is transferred to a recording sheet by a fixing unit. There are printers that use the so-called electrophotographic method of fixing on top. As one form of such a printer, an electrophotographic printer (hereinafter abbreviated as a continuous paper printer, for example, Patent Document 1) that prints information on a folding continuous recording paper with feed holes, called a fan hold paper, Printers that print using cut paper that has been cut to size (hereinafter, abbreviated as printers for cut paper) are known and widely used.
JP-A-7-146625

  In the printer as described above, a photosensitive unit including a photosensitive drum and a developing unit including a developing device are provided so as to be detachable from the housing for the purpose of repair or replacement. For example, a relatively small printer is configured such that the upper surface of the housing is opened to expose the photosensitive unit and the developing unit, and an operator can lift and remove these units from the housing.

  Also, a relatively large printer has a large photosensitive unit and developing unit, and is heavy. For this reason, if the mechanism for attaching and detaching these units (hereinafter abbreviated as “unit attaching and detaching mechanism”) is configured to lift and remove the unit above the housing in the same manner as the small printer as described above, the burden on the operator is extremely high. Will become bigger.

  Therefore, in the case of a relatively large printer, the side surface of the housing is opened to expose the photosensitive unit and the developing unit, and the unit is drawn out from the side surface along the axial direction of the photosensitive drum. According to such a configuration, the operator can take out the heavy unit from the housing without lifting it, so that the burden is reduced.

  In order to perform a good printing operation in the printer as described above, it is necessary to determine the clearance between the photosensitive drum and the developing device with high accuracy. For this reason, the developing unit is provided with a bearing for determining the clearance with the photosensitive drum to a predetermined value. Specifically, the mutual clearance is determined with high accuracy by bringing the bearing into contact with the photosensitive member of the photosensitive drum.

  As described above, the bearing which is a part of the developing unit is in contact with the photosensitive member of the photosensitive drum. For this reason, if the operator tries to take out only one of the units, the bearing in contact with the photosensitive member may be rubbed against the photosensitive member, which may be damaged. Therefore, in the case of the above-described relatively large printer, it is necessary for the operator to always pull out both units integrally even when only one of the units is to be attached or detached. Therefore, it cannot be said that the burden on the worker is sufficiently reduced.

  In view of the above circumstances, an object of the present invention is to provide a unit attaching / detaching mechanism that can reduce the burden on an operator when pulling out a photosensitive unit and a developing unit from a housing as much as possible, and a printer including the mechanism.

  A unit attaching / detaching mechanism according to an aspect of the present invention that solves the above-described problems includes a photosensitive unit that is supported inside a housing and includes a photosensitive rotator on which a latent image is formed, and a clearance between the photosensitive rotator and itself. And a developing unit for developing the latent image, which is in contact with the photosensitive rotator, for drawing out a latent image from the inside of the housing along the axial direction of the photosensitive rotator. And a unit moving means for relatively moving the photosensitive unit and the developing unit in the housing so as to separate the photosensitive rotating body from the clearance determining means.

  In the unit attaching / detaching mechanism, the unit moving means may slide at least the developing unit. In this case, the developing unit is provided with a first connector portion for establishing electrical connection with one end surface in the axial direction of the photosensitive rotator, and the unit moving means is a second moving unit that can move together with the developing unit. It may be a connector part, Comprising: The 2nd connector part electrically connected with this 1st connector part may be provided. Further, the unit moving means may further include a lever member for sliding the developing unit.

  In the unit attaching / detaching mechanism, the clearance determining means may be a bearing.

  In addition, a printer according to an aspect of the present invention that solves the above-described problems includes any of the unit attachment / detachment mechanisms described above.

  When the unit attaching / detaching mechanism of the present invention and the printer having the mechanism are employed, only one of the photosensitive unit and the developing unit can be attached / detached. Therefore, the burden of attaching / detaching the unit performed by the operator is reduced. In addition, a frame that is provided in the conventional mechanism and that can hold a large and slidable frame that holds both the units is not necessary. For this reason, the cost concerning a unit attachment / detachment mechanism can be reduced.

  A continuous paper printer that employs a unit attaching / detaching mechanism according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a side sectional view showing a configuration of a continuous paper printer 10 of the present embodiment. The continuous paper printer 10 is a so-called laser beam printing apparatus, and prints character or image information input from an external device such as a computer on fan hold paper P, which is continuous recording paper, by electrophotography using a laser beam. It is a device that outputs.

  The fan hold paper P used in the continuous paper printer 10 of the present embodiment has feed holes (not shown) formed at equal intervals on both sides at a predetermined pitch (for example, 1/2 inch in the present embodiment). (Not shown) is formed in the width direction every predetermined length. One page to be printed is defined by the interval between adjacent perforations. Note that the length of one page defined in each fan hold paper P has a standard length defined in 1/2 inch increments, as well as a special one defined in 1/6 inch increments or 1/8 inch increments. Some have a length. The continuous paper printer 10 is set so that the fan hold paper P of any size can be used.

  The fan hold paper P includes, for example, fan hold paper made of plain paper and fan hold paper made of label paper. The continuous paper printer 10 is set so that any type of fan hold paper P can be used.

  The continuous paper printer 10 is roughly divided into a housing 12 that supports various parts, a laser scanning unit (LSU) 14 that outputs laser light modulated in accordance with print information, and a laser scanning unit 14 that outputs light. A developing unit 18 including a developing unit 42 that develops a latent image corresponding to characters and image information formed on the drum 16 using toner by electrophotography, and a toner image developed by the developing unit 18 is transferred. A transfer unit 44 that transfers the fan hold paper P at the position; a transport mechanism that transports the fan hold paper P; and a fixing unit 22 that fixes the toner image transferred onto the fan hold paper P transported by the transport mechanism; , A control unit 24a for controlling a print control operation and a conveyance control operation, and a drive unit for driving various mechanisms. It is constructed from 24b.

  The drive unit 24b, which is a drive source for the various mechanisms of the continuous paper printer 10, includes a plurality of actuators that drive the various mechanisms. These actuators are all connected to the control unit 24a and are driven and controlled by the control unit 24a. The drive unit 24b can rotate, for example, the photosensitive drum 16, the cleaning roller constituting the toner cleaning unit 36, the developing roller constituting the developing unit 42, and the like.

  A carry-in port 26 into which the fan hold paper P is introduced is formed on the side surface on one end side of the housing 12 (right side surface in FIG. 1), and on the side surface on the other end side (left side surface in the diagram), A discharge port 28 through which the fan hold paper P is discharged is formed.

  The laser scanning unit 14 is unitized and is detachably disposed on the housing 12. The laser scanning unit 14 includes a laser scanning unit housing 32 having a polygon mirror 30.

  The developing unit 18 is also unitized similarly to the laser scanning unit 14 and is detachably disposed on the housing 12. A part of the developing unit 18 (details will be described later) is in contact with the photosensitive surface of the photosensitive drum 16. The photosensitive drum 16 is disposed in a unitized photosensitive unit 34 as with the developing unit 18. The photosensitive unit 34 is also detachably disposed on the housing 12.

  In the photosensitive unit 34, the photosensitive drum 16 is rotatably supported. Around the photosensitive drum 16, there are a toner cleaning unit 36 for removing untransferred toner adhering to the photosensitive surface of the photosensitive drum 16, and a static eliminating unit for uniformly removing the entire photosensitive surface of the photosensitive drum 16. 38, a charging unit 40 for uniformly charging the photosensitive surface of the photosensitive drum 16 that has been neutralized by the static eliminating unit 38, and a modulated laser beam scanned by the laser scanning unit 14, and formed on the photosensitive surface of the photosensitive drum 16. A developing unit 42 that develops the latent image with toner and a transfer unit 44 that transfers the developed toner image onto the fan hold paper P are arranged. Among the above-described components, the photosensitive unit 34 includes a toner cleaning unit 36 and a charging unit 40.

  The components around the photosensitive drum 16 described above are arranged in the above described order in the rotation direction of the photosensitive drum 16 (clockwise in the figure). Further, the transfer unit 44 includes a corona charger 46 extending over the entire length of the photosensitive drum 16 in the axial direction (a direction orthogonal to the paper surface of FIG. 1). The corona charger 46 is disposed so as to be parallel and retractable with respect to the photosensitive drum 16. By removing the photosensitive unit 34, the transport path 68 of the fan hold paper P in the transport mechanism described above is opened substantially entirely.

  Further, the transport mechanism is disposed along a transport path 68 from the transport inlet 26 to the discharge port 28. Along the conveyance path 68, a plurality of conveyance means for conveying the fan hold paper P, which are conveyance means constituting a conveyance mechanism, are arranged. The plurality of transfer means will be described in order from the carry-in entrance 26 side. In the present specification, the carry-in port 26 side of the conveyance path 68 is expressed as upstream, and the discharge port 28 side is expressed as downstream.

  A tractor unit 100 that first conveys the fan hold paper P downstream or upstream in the vicinity of the carry-in inlet 26 along the conveyance direction of the fan hold paper P (that is, the direction of traveling from upstream to downstream in FIG. 1). Is arranged. Since the tractor unit 100 is disposed in the vicinity of the carry-in entrance 26, it mainly functions to carry the fan hold paper P into the housing 12.

  The tractor unit 100 conveys the fan hold paper P by rotating the tractor belt, and a motor 102 for driving the tractor belt and a wheel for driving the tractor belt by being rotated by the motor 102. 104, a plurality of protrusions 106 arranged at a predetermined pitch on the tractor belt, an empty sensor 108, and a carry-in top sensor 110 arranged on the downstream side of the empty sensor 108. The plurality of protrusions 106 are arranged at the same pitch as the feed holes of the fan hold paper P. The fan hold paper P is supported by the tractor belt by inserting its feed holes into the plurality of protrusions 106, and is conveyed downstream or upstream depending on the driving thereof.

  The empty sensor 108 and the carry-in top sensor 110 are sensors that perform a function of determining whether or not the fan hold paper P is present at a position where the empty sensor 108 and the carry-in top sensor 110 are arranged. The empty sensor 108 and the carry-in top sensor 110 are rotatable between an upright position standing in the transport path 68 and a retracted position retracted from the transport path 68 to block the fan hold paper P being transported. A supported lever member is provided.

  The lever member of the empty sensor 108 is supported by the tractor unit 100 and is rotatable in the arrow A direction. The lever member of the carry-in top sensor 110 is supported by the tractor unit 100 and is rotatable in the arrow B direction. These lever members are biased to be in the upright position. Therefore, when there is no fan hold paper P on the empty sensor 108 or the carry-in top sensor 110, these lever members are kept in the standing position. Further, when the fan hold paper P is on the empty sensor 108 or the carry-in top sensor 110, these lever members are pressed by the fan hold paper P and moved to the retracted position.

  When the lever member is in the standing position, the empty sensor 108 or the carry-in side top sensor 110 transmits to the control unit 24a an off signal indicating that there is no fan hold paper P at the position where the lever member 108 is located. When the lever member is in the retracted position, the empty sensor 108 or the carry-in top sensor 110 transmits an ON signal indicating that the fan hold paper P is present at the position where the lever member 108 is disposed to the control unit 24a. As a result, the control unit 24a can detect the presence or absence of the fan hold paper P on the empty sensor 108 or the carry-in top sensor 110.

  Here, the empty sensor 108 mainly functions to detect a paper out of the continuous paper printer 10 (that is, the trailing edge of the fan hold paper P). The carry-in top sensor 110 mainly functions to detect a new paper feed (that is, the leading edge of the fan hold paper P) to the continuous paper printer 10.

  On the downstream side of the tractor unit 100, a conveyance auxiliary unit is disposed adjacently. This auxiliary conveyance unit is provided to prevent a deviation in the writing position of the fan hold paper P in the sub-scanning direction, which can be generated by keeping the tension of the fan hold paper P constant. And a driving roller 124, a solenoid 126, and a solenoid arm 128.

  The driven roller 122 is in a state where its rotation shaft is fixed, and is arranged so as to contact the fan hold paper P in the transport path 68, and transports the fan hold paper P (in other words, a driving roller). Is driven in accordance with the rotation 124). The driven roller 122 is made of a material having a relatively low coefficient of friction, such as plastic.

  The driving roller 124 is disposed at a position facing the driven roller 122 across the conveyance path 68 (or fan hold paper P), and is driven by the drive unit 24b to mainly convey the fan hold paper P downstream. Rotate like so. The drive roller 124 is made of a material having a relatively high friction coefficient such as rubber (a material much higher than the friction coefficient of the driven roller 122) in order to generate an appropriate conveyance force for the fan hold paper P. Is formed. Further, the drive roller 124 is movable between the rolling contact position where it is in rolling contact with the driven roller 122 and the separation position where it is separated from the driven roller 122 by the mechanism shown below, and is movable in the direction of arrow C. It is supported.

  The solenoid 126 and the solenoid arm 128 are mechanisms for moving the drive roller 124 in the direction of arrow C. The solenoid 126 slides in the direction of arrow D according to the signal transmitted from the control unit 24a, and presses the solenoid arm 128 according to the slid position. The solenoid arm 128 is formed of an elastic member, and is connected to and held by the driving roller 124.

  When the solenoid 126 is slid to the downstream side in the direction of arrow D (left side in FIG. 1), the solenoid arm 128 is pressed by a relatively strong force and elastically deforms, causing the driving roller 124 to press the driven roller 122. Give such an energizing force. As a result, the driven roller 122 and the driving roller 124 are brought into a rolling contact state (that is, the driving roller 124 is moved to the rolling contact position), and the fan hold paper P sandwiched between them is rotated by both rollers. It is conveyed by movement.

  Further, when the solenoid 126 is slid to the upstream side in the arrow D direction (the right side in FIG. 1), the solenoid arm 128 is pressed with a relatively weak force, so that almost no urging force is applied to the drive roller 124. For this reason, the driving roller 124 is separated from the driven roller 122 by a biasing force by a spring or the like (not shown). At this time, since the roller in contact with the fan hold paper P is only the driven roller 122 that cannot rotate by itself, the fan hold paper P is not transported by the transport auxiliary unit.

  The photosensitive drum 16 and the transfer unit 44 are disposed on the downstream side of the above-described conveyance auxiliary unit so as to face each other with the conveyance path 68 interposed therebetween. Here, the toner image on which the image information is formed is transferred onto the fan hold paper P.

  A tension applying mechanism that performs a function of applying a predetermined tension to the fan hold paper P is disposed further downstream of the photosensitive drum 16 and the transfer unit 44. The tension applying mechanism includes a cam 132 rotated by the drive unit 24b, a cam follower 134 that is pushed up (or pushed down) in contact with the cam 132, and a predetermined tension applied to the fan hold paper P supported by the cam follower 134. A tension plate 136 for application and a photo interrupter 138 for monitoring the position of the tension plate 136 for applying a predetermined tension to the fan hold paper P are configured.

  The cam 132 has an elliptical shape, is driven by the drive unit 24b, and moves eccentrically around the eccentric position. The cam follower 134 is urged so that a part thereof is pressed against the outer peripheral portion of the cam 132 by a spring (not shown). When the cam 132 continues to make contact with the cam follower 134 while performing an eccentric motion, the eccentric motion is converted into a reciprocating motion by the cam follower 134. That is, the cam follower 134 can perform a predetermined reciprocating motion by the action of the cam 132.

  The tension plate 136 is a plate-like member having a length that extends over substantially the entire width direction of the fan hold paper P, and moves vertically with respect to the fan hold paper P (in the direction of arrow E in FIG. 1). This is for applying a predetermined tension to the fan hold paper P by pressing substantially the entire width direction of the fan hold paper P. Since the tension plate 136 is fixed to the cam follower 134, the tension plate 136 operates integrally with the cam follower 134. More specifically, the tension plate 136 operates in the direction of arrow E to press the fan hold paper P from the back side of the surface on which the toner image is transferred or to move away from the fan hold paper P.

  As the tension plate 136 moves above the housing 12 (ie, the upper side in FIG. 1), the tension of the fan hold paper P applied by the tension plate 136 increases, and the tension plate 136 moves below the housing 12 (ie, the lower side in FIG. 1). The tension of the fan hold paper P applied by the tension plate 136 decreases as the movement to the side) increases. Further, when the tension plate 136 moves downward from a certain point, it is separated from the fan hold paper P, and the tension of the tension plate 136 on the fan hold paper P is no longer applied. The case where the tension plate 136 is separated from the fan hold paper P is mainly when the fan hold paper P is not conveyed onto the tension plate 136.

  The tension plate 136 presses the fan hold paper P with a predetermined pressing force by the action of the cam 132, the cam follower 134, and the spring. Therefore, when the tension of the fan hold paper P is increased, the tension plate 136 is pushed down below the housing 12. When the tension of the fan hold paper P decreases, the tension plate 136 is pushed up above the housing 12. The control unit 24a can know the tension of the fan hold paper P by detecting the movement of the tension plate 136.

  Here, the photo interrupter 138 is a well-known transmissive photo interrupter for detecting the position of the tension plate 136, and outputs the detection result to the control unit 24a. That is, the control unit 24a can know the movement of the tension plate 136 by detecting the detection result output from the photo interrupter 138. Thus, the control unit 24a can detect the tension currently applied to the fan hold paper P.

  The control unit 24a appropriately adjusts the difference in the conveyance speed between the tractor unit 100 and a later-described discharge roller pair 510 based on the detected tension. For example, when the detected tension exceeds a predetermined value, the conveyance speed by the discharge roller pair 510 is faster than the conveyance speed by the tractor unit 100, and the fan hold paper P is pulled toward the discharge roller pair 510 side. Means. For this reason, the control unit 24a reduces the conveyance speed by the discharge roller pair 510 and lowers the tension of the fan hold paper P. Further, when the detected tension falls below a predetermined value, the conveyance speed by the discharge roller pair 510 is slower than the conveyance speed by the tractor unit 100, and the fan hold paper P between both conveyance means is loosened. means. For this reason, the control unit 24a increases the conveyance speed of the discharge roller pair 510 and increases the tension of the fan hold paper P.

  A fixing unit 22 is disposed on the downstream side of the tension applying mechanism. The fixing unit 22 includes a heat roller 22 a that is heated by a heat source such as an internal halogen lamp, and a press roller 22 b that is disposed at a position facing the heat roller 22 a across the conveyance path 68. The press roller 22b is pressed against the heat roller 22a by a biasing means (not shown). When the fan hold paper P is sandwiched between these rollers 22a and 22b and heated and pressed, the toner transferred by the transfer unit 44 is fixed to the fan hold paper P. The heat roller 22a is rotated clockwise by the drive unit 24b. The press roller 22b is driven according to the conveyance of the fan hold paper P (in other words, the rotation of the heat roller 22a) and has a function of applying a predetermined pressure to the heat roller 22a. Yes.

  A discharge-side top sensor 130 is disposed on the downstream side of the fixing unit 22 described above. The discharge-side top sensor 130 is a sensor that performs a function of determining whether or not the fan hold paper P is present at a position where the discharge-side top sensor 130 is disposed. The discharge-side top sensor 130 is a lever member that is rotatably supported between an upright position standing in the conveyance path 68 so as to block the fan hold paper P being conveyed and a retracted position retracted from the conveyance path 68. It has.

  The lever member of the discharge-side top sensor 130 is rotatable in the direction of arrow F and is urged to be in the standing position. Therefore, when there is no fan hold paper P on the discharge side top sensor 130, these lever members are kept in the standing position. When the fan hold paper P is present on the discharge side top sensor 130, the lever member is pressed by the fan hold paper P and moved to the retreat position.

  When the lever member is in the standing position, the discharge-side top sensor 130 transmits an off signal indicating that the fan hold paper P is not present at the position where the discharge-side top sensor 130 is disposed to the control unit 24a. When the lever member is at the retracted position, the discharge-side top sensor 130 transmits an ON signal indicating that the fan hold paper P is present at the position where the discharge-side top sensor 130 is disposed to the control unit 24a. As a result, the control unit 24a can detect the presence or absence of the fan hold paper P on the discharge-side top sensor 130.

  Here, the discharge-side top sensor 130 mainly functions to detect a new paper supply to the continuous paper printer 10 (that is, the leading edge of the fan hold paper P).

  A paper discharge roller pair 510 is disposed adjacent to the downstream side of the above-described discharge side top sensor 130. The paper discharge roller pair 510 is a conveying means for discharging the fan hold paper P from the discharge port 28, and is a paper discharge driven roller 510a whose rotation shaft is fixedly supported, and a paper discharge driven with the conveyance path 68 interposed therebetween. The paper discharge driving roller 510b is disposed at a position facing the roller 510a.

  The paper discharge driven roller 510a is disposed so as to be in contact with the fan hold paper P in the transport path 68, and according to the transport of the fan hold paper P (in other words, the rotation of the paper discharge drive roller 510b). It will be driven. The paper discharge driven roller 510a is formed of a material having a relatively low coefficient of friction such as plastic.

  The paper discharge drive roller 510b is driven by the drive unit 24b and rotates mainly to convey the fan hold paper P downstream. In order to generate an appropriate conveyance force for the fan hold paper P, the discharge driving roller 510b is made of a material having a relatively high friction coefficient such as rubber (much more than the friction coefficient of the discharge driven roller 510a). High material). Further, the paper discharge driving roller 510b is supported so as to be movable between a rolling contact position that is in rolling contact with the paper discharge driven roller 510a and a separation position that is separated from the paper discharge driven roller 510a. The paper discharge roller pair 510 is mounted on the fixing unit sliding mechanism so that it can slide from the inside of the housing 12 to the outside, like the fixing unit 22.

  Next, a unit attaching / detaching mechanism which is a characteristic part of the embodiment of the present invention will be described. The unit attaching / detaching mechanism of the embodiment of the present invention is a mechanism for attaching / detaching the photosensitive unit 34 and the developing unit 18 from the housing 12. According to the unit attaching / detaching mechanism as in the present embodiment, attaching / detaching of only one of the photosensitive unit 34 and the developing unit 18 which cannot be achieved by the conventional mechanism can be performed. Therefore, the burden of attaching / detaching the unit performed by the operator is reduced. In addition, a frame that is provided in the conventional mechanism and that can hold a large and slidable frame that holds both the units is not necessary. For this reason, the cost concerning a unit attachment / detachment mechanism can be reduced.

  FIG. 2 is an external perspective view showing the housing 12a which is an inner frame by removing the outer frame constituting the housing 12 for convenience of explanation. FIG. 2 shows the housing 12a and a part of the unit attaching / detaching mechanism attached to the housing 12a, which is a characteristic part of the present embodiment. In FIG. 2, as in FIG. 1, the left side in the figure is the discharge port 28 side, and the right side in the figure is the carry-in port 26 side. FIG. 3 is a cross-sectional view of the continuous paper printer 10 as viewed from above, and shows a cross-section of a part of the structure including a unit attaching / detaching mechanism that is a characteristic part of the embodiment of the present invention. It is. FIG. 4 is a side view showing a state in which the photosensitive unit 34 and the developing unit 18 are housed in the housing 12, and shows these units and their peripheral portions. Below, with reference to FIGS. 2-4, the structure and effect | action of the unit attachment / detachment mechanism of embodiment of this invention are demonstrated.

  First, the configuration and operation for supporting the photosensitive unit 34 in the housing 12a will be described.

  An opening 302 for accommodating the photosensitive unit 34 and the developing unit 18 therein is formed on the side surface of the housing 12a. A slide rail 304 for supporting the photosensitive unit 34 is formed around the opening 302. The slide rail 304 extends over the entire length of the photosensitive drum 16 in the axial direction, and one end of the slide rail 304 is positioned around the opening 302 as shown in FIG. The photosensitive unit 34 is formed with a support portion 34 a so as to correspond to the slide rail 304 over the entire length in the axial direction. When the photosensitive unit 34 is housed in the housing 12a, the supporting unit 34a is aligned with the slide rail 304 while the photosensitive unit 34 is inserted through the opening 302, and is slid in the axial direction.

  However, the photosensitive unit 34 cannot be stably supported on the housing 12a only by the above-described slide mechanism. For this reason, two guide pins 306 for supporting the photosensitive unit 34 are formed in the periphery of the opening 302, and the surface of the housing 12a facing the surface on which the opening 302 is formed is also the same. Two guide pins 306 are formed. In the photosensitive unit 34, four guide holes 34b for inserting the guide pins are formed at positions corresponding to the four guide pins 306 described above. When the photosensitive unit 34 is completely accommodated in the housing 12a, the guide pins 306 and the guide holes 34b are fitted.

  Further, the housing 12 a is provided with a storage lever 312 that acts to prevent the photosensitive unit 34 from moving from the opening 302 to the outside. The storage lever 312 is supported on the side surface of the housing 12a so as to be rotatable in the arrow G direction around the support shaft 314. When the storage lever 312 is rotated away from the housing 12a, the entire opening 302 is opened (the position of the storage lever 312 at this time is the open position). Further, as shown in FIG. 2, when the distal end of the storage lever 312 is rotated so as to contact the housing 12 a, the storage lever 312 is positioned so as to cross the opening 302, and the opening 302 is divided by the storage lever 312. (The position of the storage lever 312 at this time is set as the storage position).

  After the storage lever 312 is rotated to the storage position, when the set lever 316 (described in detail later) is rotated from the position indicated by the one-dot chain line in FIG. 4 to the position indicated by the solid line, the storage lever 312 is The leading end is restrained by the set lever 316, and the rotation to the open position is prohibited. That is, the storage lever 312 is fixed at the storage position.

  As shown in FIG. 4, when the periphery of the opening 302 is observed from the axial direction of the photosensitive drum 16 in a state where the storage lever 312 is rotated to the storage position, the photosensitive unit 34 and the storage lever 312 partially overlap each other. So positioned. Therefore, when the photosensitive unit 34 is moved from the opening 302 to the outside, the photosensitive unit 34 and the storage lever 312 come into contact with each other. That is, the photosensitive unit 34 is prohibited from moving outward from the opening 302 by the storage lever 312.

  The photosensitive unit 34 is stably supported in the housing 12a by the above-described means, that is, the action of the slide rail 304, the guide pin 306, and the storage lever 312.

  Next, the configuration and operation for supporting the developing unit 18 in the housing 12a will be described.

  A support rail 308 and a pressure plate 310 for supporting the developing unit 18 are formed inside the housing 12a so as to be hung on the surface of the housing 12a located on the opposite side from the vicinity of the opening 302. The developing unit 18 is formed with a support portion (not shown) formed to correspond to the support rail 308 and aligned with the support rail 308. As shown in FIG. 3, the pressing plate 310 is rotatable in the direction of the arrow H by a support shaft 320 having the same overall length as that of the pressing plate 310 and being arranged substantially in parallel with the four supporting columns 318. Is provided.

  The support shaft 320 is arranged to be elastically deformed so as to slightly protrude and bend in a direction facing the pressing plate 310. For this reason, the support shaft 320 acts to return to the original shape (that is, a shape in which the central axis is a straight line), and urges the pressing plate 310 in a direction away from itself. That is, the pressing plate 310 is always urged away from the support shaft 320.

  A set lever 316 is attached to the end of the support shaft 320 on the opening 302 side. The set lever 316 is supported so as to be rotatable in the direction of arrow H about the support shaft 320 and is fixed relative to the pressing plate 310. Note that the pressing plate 310 and the set lever 316 can be rotated from the position indicated by the one-dot chain line in FIG. 4 to the position indicated by the solid line. Further, the positions of the pressing plate 310 and the set lever 316 indicated by the one-dot chain line indicate that the developing unit 18 is not completely supported in the housing 12a (or the developing unit 18 is not accommodated in the housing 12a). ) (Hereinafter, abbreviated as an open position), and the positions of the pressing plate 310 and the set lever 316 indicated by solid lines are the positions (hereinafter referred to as the development unit 18) in a state where the developing unit 18 is housed and supported in the housing 12a. It is abbreviated as “support position”.

  While the developing unit 18 is positioned in the housing 12a, the pressing plate 310 is always positioned so as to be substantially in contact with the wall portion 18a of the developing unit 18. For example, when the developing unit 18 is inserted into the opening 302 and the support portion (not shown) is aligned with the support rail 308 and is slid in the same direction as the photosensitive unit 34, the pressing plate 310 is indicated by a one-dot chain line in FIG. As shown, the tip portion is positioned so as to be covered by the curved surface portion of the wall portion 18a. At this time, a slight clearance exists between the pressing plate 310 and the wall portion 18a.

  Further, when the pressing lever 310 is rotated from the open position to the supporting position by turning the set lever 316, the pressing plate 310 and the wall portion 18a come into contact with each other during the rotation. When the pressing plate 310 is further rotated from this contact position, the pressing plate 310 presses the wall portion 18a by the urging force applied to the support shaft 320, and the entire developing unit 18 is moved to the photosensitive unit 34. Slide it in the direction of arrow I.

  Here, the developing unit 18 includes a bearing 18 b for determining a clearance between the developing unit 18 and the photosensitive drum 16, and a guide pin 18 c for supporting the photosensitive drum 16. As described above, when the developing unit 18 is pressed by the pressing plate 310 and slid toward the photosensitive unit 34, the bearing 18 b comes into contact with the photosensitive member of the photosensitive drum 16. At this time, the pressing plate 310 is rotated to the support position.

  The bearing 18b is a metallic ball bearing whose surface is polished with high accuracy, and is provided to rotate itself when the photosensitive drum 16 rotates in a contact state. For this reason, even if the photosensitive drum 16 rotates, the bearing 18b is always in contact. By always bringing the bearing 18b into contact with the photosensitive member, the clearance between the photosensitive drum 16 and the developing unit 18 is determined with high accuracy, and the continuous paper printer 10 can execute the printing operation satisfactorily.

  The developing unit 18 further includes a support pin 18c. The photosensitive unit 34 has a groove 34c at a position corresponding to the support pin 18c. The support pin 18c and the groove 34c are engaged with each other while the bearing 18b abuts on the photosensitive drum 16.

  The storage lever 312 acts to prevent the developing unit 18 from moving from the opening 302 to the outside, as in the case of the photosensitive unit 34. In other words, when the periphery of the opening 302 is observed from the axial direction of the photosensitive drum 16 in a state where the storage lever 312 is rotated to the storage position as shown in FIG. It is located so that a part overlaps. For this reason, when the developing unit 18 is to be moved from the opening 302 to the outside, the developing unit 18 and the storage lever 312 come into contact with each other, and movement of the developing unit 18 to the outside is prohibited.

  The developing unit 18 is stably supported in the housing 12a by the above means, that is, the action of the support rail 308, the pressing plate 310, the groove 34c, and the storage lever 312.

  The set lever 316 is formed with a notch 316a for fixing the set lever 316 at the support position. The housing 12a supports a notch pin 322 at a position corresponding to the notch 316a when the set lever 316 is rotated to the support position. The notch pin 322 is supported so as to be movable in the direction of the arrow J, and is biased toward the set lever 316 by a spring (not shown).

  When the set lever 316 is in the open position, the notch pin 322 is in contact with the wall portion of the set lever 316. When the set lever 316 is rotated to the support position, the positions of the notch pin 322 and the notch 316a are aligned, and the notch pin 322 is inserted into the notch 316a by the above-described biasing force. By this fitting, the set lever 316 does not rotate from the support position unless a large external force is applied. Therefore, a situation occurs in which the function of holding the storage lever 312 (more specifically, the function of fixing the photosensitive unit 34 and the developing unit 18 in the housing 12a) is lost due to the rotation of the set lever 316 during the operation of the printer. do not do.

  The photosensitive unit 34 and the developing unit 18 are electrically connected to the control unit 24a and the driving unit 24b when housed in the housing 12 as described above.

  A connector portion 324 that is electrically connected to the control unit 24a and the drive unit 24b is disposed on the surface of the housing 12a that faces the surface on which the opening 302 is formed. In addition, a connector portion 34d is provided on one end face of the photosensitive unit 34 for electrical connection with an external device. These connector portions are arranged so that they are connected to each other when the photosensitive unit 34 is slid from the opening 302 side and stored in the housing 12a.

  The photosensitive unit 34 is accommodated in the housing 12a only by movement in a direction orthogonal to the paper surface of FIG. 4, whereas the developing unit 18 is moved in the housing 12a by movement in a direction orthogonal to and parallel to the paper surface of FIG. It is stored in. Therefore, the developing unit 18 cannot achieve electrical connection with the configuration such as the connector portion 324 and the connector portion 34d described above.

  FIG. 5 is an external perspective view showing a state in which the developing unit 18 accommodated in the housing 12a is electrically connected. FIG. 6 is a view showing a connector holding mechanism 330 supported by the housing 12a for electrically connecting the developing unit 18. The configuration and operation of the connector holding mechanism 330 for electrically connecting the developing unit 18 will be described below with reference to FIGS.

  On one end surface of the developing unit 18, a connector portion 18d is provided for electrical connection with an external device. An opening 326 is formed on the surface of the housing 12a that faces the surface on which the opening 302 is formed. When the developing unit 18 is slid from the opening 302 side and accommodated in the housing 12a, a part of the connector 18d provided on the end surface thereof is positioned so as to pass through the opening 326.

  A holding plate 332 that is a component of the connector holding mechanism 330 and covers the opening 326 is attached to the surface on which the opening 326 is formed. Two saddle holes 332a are formed on the surface of the holding plate 332 facing the opening 326. These daruma holes 332a are formed of a relatively large circular portion and a linear portion having a width narrower than the diameter of the circular portion and parallel to the slide direction (arrow I direction) of the developing unit 18.

  A movable pin 334 is inserted through the daruma hole 332a. The diameter of the movable pin 334 is larger than the diameter of the circular portion of the round hole 332a. Further, a tapered portion is formed from the plate portion to the shaft portion.

  A compression ring 336 inserted through the shaft portion of the movable pin 334 is disposed at a position sandwiching the holding plate 332 and facing the dish portion of the movable pin 334. The outer diameter of the compression ring 336 is larger than the diameter of the circular portion of the round hole 332a.

  The tip of the shaft portion of the movable pin 334 is attached to the movable plate 338 disposed between the opening 326 and the holding plate 332. A connector spring 340 is wound around the shaft portion of the movable pin 334. The connector spring 340 is a compression coil spring, one end of which is in contact with the movable plate 338 and the other end is in contact with the compression ring 336. The natural length of the connector spring 340 is longer than the distance between the movable plate 338 and the compression ring 336 when the movable pin 334 is attached to the movable plate 338. Therefore, when wound around the movable pin 334 as shown in FIGS. 5 and 6, the connector spring 340 is disposed in a compressed state. For this reason, the connector spring 340 urges the holding plate 332 and the movable plate 338 so as to separate them from each other. As a result, the plate portion of the movable pin 334 and the compression ring 336 sandwich the holding plate 332 by the biasing force of the connector spring 340.

  In the above-described state, the movable pin 334 is in contact with the peripheral portion of the boring hole 332a by the tapered portion formed in itself. Therefore, the pressing force of the movable pin 334 against the holding plate 332 due to the biasing force of the connector spring 340 is divided into the axial direction of the movable pin 334 and the direction orthogonal to the axial direction. The holding plate 332 and the compression ring 336 are both formed of a material having a low friction coefficient. That is, the load in the sliding direction of the developing unit 18 with respect to the movable pin 334 is relatively light. Therefore, the movable pin 334 can smoothly slide in the above-mentioned direction in the darling hole 332a. For this reason, the movable plate 338 fixed relative to the movable pin 334 can slide in the aforementioned direction with respect to the housing 12a fixed relative to the holding plate 332.

  A connector mounting hole 338 a is formed on the surface of the movable plate 338 that faces the opening 326. A connector portion 328 that is electrically connected to the control unit 24a and the drive unit 24b is attached to the movable plate 338 so that the connection portion is exposed from the connector attachment hole 338a. In addition, two rough guide pins 342 for smoothly attaching the connector portion 18d to the connector portion 328 are provided in the peripheral portion of the connector attachment hole 338a. A signal cable (not shown) drawn from the connector portion 328 passes through an opening 332 formed in the holding plate 332 and is connected to the control unit 24a and the drive unit 24b.

  In a state before the developing unit 18 is slid in the direction of the arrow I, the movable pin 334 is located at a circular portion of the darling hole 332a. When positioned in this circular portion, the movable pin 334 can be moved within the circular portion with a relatively low external force.

  When the developing unit 18 is slid from the opening 302 side and stored in the housing 12a, the rough guide pin 342 is inserted into a rough guide hole (not shown) formed in the developing unit 18.

  A taper having a relatively low inclination angle is formed at the tip of the rough guide pin 342. For this reason, when the developing unit 18 is slid slightly off the original position, the rough guide hole is brought into contact with the tapered portion of the rough guide pin 342.

  Here, as described above, the movable pin 334 can move relatively easily within the circular portion of the darling hole 332a. For this reason, the rough guide pin 342 is moved toward the center of the rough guide hole so that the movable pin 334 is moved within the circular portion of the saddle hole 332a by the above-described contact. By this movement, the connector portion 328 is gradually moved to the alignment position with the connector portion 18d so that the deviation of the developing unit 18 is gradually canceled. When the developing unit 18 is completely pushed into the housing 12a, the positions of the connector portion 18d and the connector portion 328 are aligned, and the connector portions are connected to each other.

  Since the movable pin 334 can slide with respect to the holding plate 332 within the range of the blind hole 332a, the connector unit is connected to each other, the set lever 316 is rotated to the storage position, and the developing unit 18 is moved in the direction of arrow I. Is slid along the straight portion of the daruma hole 332a formed in parallel with the direction. Accordingly, the connector portion 328 fixed relatively to the movable pin 334 is similarly slid in the direction of arrow I. That is, even if the developing unit 18 is slid in the direction of the arrow I, the connector portion 328 and the connector portion 18d are slid together in a connected state. For this reason, the connection state between the control unit 24 a and the drive unit 24 b and the developing unit 18 is maintained regardless of the slide of the developing unit 18.

  The mounting of the developing unit 18 and the photosensitive unit 34 to the housing 12a has been described above. It should be noted that when removing these units, the procedure may be performed in the reverse order of the above description. That is, when removing these units from the housing 12a, first, the set lever 316 is rotated to the open position, and the developing unit 18 (more precisely, the bearing 18b from the photosensitive member of the photosensitive drum 16) is pulled away from the photosensitive unit 34. As a result, the bearing 18b does not rub against the photoconductor, so that the units can be individually taken out from the housing 12a by rotating the storage lever 312 to the open position. For this reason, the operator can take out only the unit that needs replacement or repair from the housing 12a. Therefore, the burden on the operator is reduced.

  The above is the embodiment of the present invention. The present invention is not limited to these embodiments and can be modified in various ranges.

1 is a side sectional view showing a configuration of a continuous paper printer according to an embodiment of the present invention. It is the external appearance perspective view which removed the outer frame of the housing and exposed the inner frame and a part of the unit attaching / detaching mechanism. It is sectional drawing when the continuous paper printer of embodiment of this invention is observed from upper direction, Comprising: It is the figure which showed the cross section of the one part structure containing a unit attachment / detachment mechanism. FIG. 3 is a side view showing a state in which the photosensitive unit and the developing unit according to the embodiment of the present invention are housed in a housing, and shows these units and their peripheral portions. FIG. 2 is an external perspective view showing a state in which the developing units of the embodiment of the present invention are electrically connected. FIG. 5 is a view showing a connector holding mechanism for electrically connecting a developing unit supported by a housing 12 according to an embodiment of the present invention.

Explanation of symbols

10 continuous paper printer 12a housing 16 photosensitive drum 18 developing unit 18b bearing 34 photosensitive unit 310 pressing plate 316 set lever 330 connector holding mechanism

Claims (6)

A photosensitive unit including a photosensitive rotator that is supported in the housing and on which a latent image is formed, and clearance determining means for determining a clearance between the photosensitive rotator and itself are brought into contact with the photosensitive rotator. A developing unit for developing the latent image, and a unit attaching / detaching mechanism for pulling out the interior from the housing along the axial direction of the photosensitive rotator,
A unit attaching / detaching mechanism comprising unit moving means for relatively moving the photosensitive unit and the developing unit in the housing so as to separate the photosensitive rotating body and the clearance determining means.   The unit attaching / detaching mechanism according to claim 1, wherein the unit moving unit slides at least the developing unit. The developing unit includes a first connector portion for electrically connecting to one end surface in the axial direction,
The unit moving means includes a second connector portion that is movable together with the developing unit and is electrically connected to the first connector portion. Item 3. The unit attaching / detaching mechanism according to Item 2.   The unit attaching / detaching mechanism according to claim 2, wherein the unit moving unit further includes a lever member for sliding the developing unit.   5. The unit attaching / detaching mechanism according to claim 1, wherein the clearance determining means is a bearing.   A printer comprising the unit attaching / detaching mechanism according to any one of claims 1 to 5.

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