JP5014806B2 - Image forming apparatus and linear scale exchanging method in image forming apparatus - Google Patents

Description

The present invention relates to an image forming apparatus, a linear scale replacing the images forming apparatus.

  2. Related Art As an image forming apparatus such as a printer, a facsimile machine, a copying apparatus, and a composite machine of these, for example, an ink jet recording apparatus is known as an image forming apparatus of a liquid discharge recording method using a recording head that discharges a recording liquid droplet. . This ink jet recording apparatus means a recording liquid (for example, ink droplets) conveyed from a recording head (not limited to paper, including OHP, and can be attached to ink droplets and other liquids). And recording medium or recording medium, recording paper, recording paper, etc.) to form an image (recording, printing, printing, and printing are also used synonymously). There is a serial type in which the recording head moves in the main scanning direction.

  In such an image forming apparatus, a linear scale (encoder scale) stretched along the main scanning area of the carriage and a scale of the linear scale are used to control the moving amount and moving speed of the carriage as a moving body. And a linear encoder composed of an encoder sensor that detects the movement of the motor, and performs drive control of a motor that drives the carriage based on a signal output from the linear encoder in accordance with the movement of the carriage.

  However, in a liquid ejection type image forming apparatus, in order to form an image by ejecting a recording liquid, mist or the like may adhere to the linear scale and cause contamination, and the linear scale for detecting the movement of the carriage. If it becomes dirty, the detection signal will be disturbed and the movement (position and speed) control of the carriage will be disturbed, so that the droplet landing accuracy will be lowered and the image quality will be lowered.

Therefore, in Patent Document 1, an encoder scale is wound around the first reel and the second reel, and the distance between the position of the ink mist adhering to the position farthest from the detection plate and the detection plate is obtained. The encoder scale of the attached measurement unit is wound on the second reel, and the unused encoder scale wound on the first reel is sent to the measurement unit, so that the encoder scale can be used for a long period of time. Are listed.
JP-A-2005-238513

In Patent Document 2, it is not necessary to remove the linear scale when exchanging the carriage and the encoder sensor, and the encoder sensor is held in order to allow the operator to work without fear of touching it by hand. The sensor holding member is provided so as to be detachable in the vertical direction.
JP 2006-187905 A

In addition, Patent Document 3 discloses an ink jet recording head having at least one of a light emitting unit capable of emitting light to an encoder scale and a light receiving unit capable of receiving light from the light emitting unit via the encoder scale. Is provided with an adjusting mechanism for properly maintaining the position of the encoder sensor and the encoder film in the optical axis direction. Patent Document 5 discloses a magnetic linear encoder comprising a magnetized scale and a magnetic head movable along the scale. The scale has holding means for detachably holding the magnetic head, and further has tension applying and attaching means for applying tension to the scale and attaching it to the side plate of the recording apparatus main body. .
JP 2006-150672 A JP 2006-142701 A Japanese Patent Laid-Open No. 05-298628

  In the image forming apparatus of the serial type ink jet recording system as described above, mist or the like may adhere to the linear scale to form the image by ejecting the recording liquid to detect the movement of the carriage. If the linear scale is dirty, the detection signal is disturbed and the movement (position and speed) control of the carriage is disturbed, so that the droplet landing accuracy is lowered and the image quality is lowered.

  However, in the past, so-called personal-use inkjet recording devices have been the mainstream, and the replacement of the linear scale is not planned for such inkjet recording devices because the unit price of the device itself is low. When replacing, the recording apparatus itself is replaced.

  However, in a liquid discharge type image forming apparatus developed for business use, it is not possible to replace the entire apparatus simply because the linear scale is dirty. It has become an important issue to improve the exchangeability. In this case, it is conceivable that the image forming unit is unitized and only the image forming unit is replaced, but this still costs more than the case where only the linear case is replaced.

  Even when the linear scale is replaceable, the linear scale is often made of transparent PET, and human sebum is easily attached at the time of replacement, and a linear scale reading error occurs due to sebum adhesion. There is a problem that it is necessary to be able to perform the replacement work so as not to adhere.

  The above-mentioned Patent Documents 1 and 2 do not plan to replace the linear scale, and the configuration as in Patent Document 1 requires a linear scale winding mechanism, a mist position detection mechanism, and the like. There is a problem that the cost becomes higher.

The present invention has been made in view of the above problems, an object low lessen the Rukoto the risk of damage occurrence with respect to the linear scale when the linear scale replacement.

  In order to solve the above problems, an image forming apparatus according to the present invention has a holding member capable of detachably holding one end of a linear scale in a carriage, and the carriage holding member can be used when the linear scale is replaced. The carriage is moved while holding one end of the linear scale to guide the one end of the linear scale to the vicinity of the fixed position.

  Here, it can be set as the structure which has a hook part which the holding member latches the hole part formed in the one end part of a linear scale. Moreover, it can be set as the structure which has a slit part in which the holding member fits the one end part of a linear scale, and it is preferable in this case that the protection member is attached to the slit part of a holding member.

  Moreover, it can be set as the structure which has a clip part which the holding member pinches | interposes the one end part of a linear scale. The holding member can be configured to be movable relative to the carriage. In addition, the holding member can be configured to have a plurality of holding members, and in this case, the holding member can be configured to be provided at both ends in the moving direction of the carriage, and among the plurality of holding members, relative to the fixed position of the linear scale. The holding members that are separated from each other can have a concave cross-sectional shape.

  Further, the side plate to which the guide member holding the carriage movably is fixed may be provided with a hole through which the linear scale can pass, and in this case, the inner peripheral surface of the hole through which the linear scale can pass is provided. Is preferably provided with a protective member. Further, the apparatus main body can be configured to include a main body side holding member that detachably holds one end of the linear scale.

  The replacement method of the replacement linear scale in the image forming apparatus according to the present invention includes the step of fixing the adhesive material provided at the end of the bag-shaped protective material covering the replacement linear scale to the apparatus main body, A step of holding one end portion on a holding member provided on a carriage mounted with a recording head, a step of moving the carriage to a fixed position side for fixing one end portion of the replacement linear scale, and extracting the replacement linear scale from the protective material It was set as the structure containing.

  According to the image forming apparatus of the present invention, the carriage has a holding member capable of detachably holding one end portion of the linear scale, and the one end portion of the linear scale is attached to the holding member of the carriage when the linear scale is replaced. Since the carriage is moved in the held state and one end of the linear scale is guided to the vicinity of the fixed position, the end of the linear scale is held by hand and passed through the back of the carriage to the regular fixed position. Can be eliminated, and when replacing the linear scale, it is possible to reduce the risk of occurrence of damage associated with the replacement work, such as adhesion of human sebum on the surface of the linear scale.

  According to the replacement method of the replacement linear scale in the image forming apparatus according to the present invention, the step of fixing the adhesive material provided at the end of the bag-shaped protective material covering the replacement linear scale to the apparatus body, the replacement linear A step of holding one end of the scale on a holding member provided on a carriage on which the recording head is mounted, the carriage is moved to a fixed position for fixing one end of the replacement linear scale, and the replacement linear scale is moved from the protective material. Since it was set as the structure including the extraction process, the damage to the linear scale surface which generate | occur | produces when removing a protective material from a linear scale can be reduced.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. An example of an image forming apparatus according to the present invention will be described with reference to FIGS. 1 is a schematic configuration diagram showing the overall configuration of the image forming apparatus, FIG. 2 is a plan explanatory diagram of an engine unit portion of the apparatus, FIG. 3 is a schematic front explanatory diagram of the engine unit portion, and FIG. It is a schematic perspective explanatory drawing of a unit part.

  This image forming apparatus has an image forming part (means) 2 for forming an image, a sub-scanning conveying part (means) 3, etc. in the inside (enclosure) of the apparatus main body 1. A recording medium (hereinafter referred to as “paper”, but the material is not limited to paper) 5 serving as a transported member is separated and fed one by one from a paper feeding unit (means) 4 serving as a housing unit. Paper is formed and the sub-scanning conveyance unit 3 intermittently conveys the paper 5 at a position facing the image forming unit 2 while the image forming unit 2 ejects droplets onto the paper 5 to form (record) a desired image. After that, the paper 5 is discharged onto a paper discharge tray 7 formed on the upper surface of the apparatus main body 1 through the paper discharge conveyance unit 6. The image forming unit 2 and the sub-scanning conveyance unit 3 are unitized to form an engine unit 100 that is detachably attached to the apparatus main body 1.

  The image forming apparatus also has an image reading unit (scanner) for reading an image above the discharge tray 7 above the apparatus main body 1 as an input system for image data (print data) formed by the image forming unit 2. Part) 11. The image reading unit 11 includes a scanning optical system 15 including an illumination light source 13 and a mirror 14 and a scanning optical system 18 including mirrors 16 and 17. The scanned document image is read as an image signal by the image reading element 20 disposed behind the lens 19, and the read image signal is digitized and subjected to image processing, and the image-processed print data is printed. be able to. A pressure plate 10 is provided on the contact glass 12 for pressing the document.

  Here, as shown in FIG. 2, the image forming section 2 of the image forming apparatus includes a carriage guide (guide rod) 21 that is a main guide member horizontally mounted between the front side plate 101F and the rear side plate 101R and the rear side. A guide stay 22 (see FIGS. 3 and 4), which is a slave guide member provided on the stay 101B side, holds the carriage 23 so as to be movable in the main scanning direction, and the main scanning motor 27 connects the drive pulley 28A and the driven pulley 28B. Is moved and scanned in the main scanning direction via a timing belt 29 spanned between the two.

  On the carriage 23, recording heads 24k1 and 24k2 each composed of two droplet discharge heads for discharging black (K) ink, cyan (C) ink, magenta (M) ink, and yellow (Y). A total of five droplet ejection heads, recording heads 24c, 24m, and 24y each composed of one droplet ejection head that ejects ink (when not distinguishing colors and collectively referred to as “recording head 24”), are included. A shuttle type is mounted, in which the carriage 23 is moved in the main scanning direction, and droplets are ejected from the recording head 24 while the paper 5 is fed in the paper transporting direction (sub-scanning direction) by the sub-scanning transport unit 3. Yes.

  In addition, a sub tank 25 is mounted on the carriage 23 in order to supply a recording liquid of a required color to each recording head 24. On the other hand, as shown in FIG. 1, recording liquid containing black (K) ink, cyan (C) ink, magenta (M) ink, and yellow (Y) ink from the front of the apparatus main body 1 to the cartridge mounting portion 26A. Each color ink cartridge 26 can be detachably mounted, and ink (recording liquid) is supplied from each color ink cartridge 26 to each color sub-tank 25 via a tube (not shown). The black ink is supplied from one ink cartridge 26 to the two sub tanks 25.

  The recording head 24 uses a piezoelectric element as a pressure generating means (actuator means) for pressurizing the ink in the ink flow path (pressure generation chamber) to deform the vibration plate that forms the wall surface of the ink flow path. A so-called piezo type that discharges ink droplets by changing the volume in the flow channel, or discharges ink droplets with a pressure generated by heating the ink in the ink flow channel using a heating resistor to generate bubbles. The so-called thermal type, the diaphragm that forms the wall surface of the ink flow path and the electrode are placed opposite to each other, and the diaphragm is deformed by the electrostatic force generated between the vibration plate and the electrode, thereby the ink flow path inner volume It is possible to use an electrostatic type or the like that discharges ink droplets by changing the above.

  2 to 4, a linear scale 128 having a slit is provided between the front plate 101F and the rear plate 101R along the main scanning direction of the carriage 23. An encoder sensor 129 made up of a transmissive photosensor that detects the slits of the linear scale 128 is provided, and the linear scale 128 and the encoder sensor 129 constitute a linear encoder that detects the movement of the carriage 23.

  Further, as shown in FIG. 2, a maintenance / recovery mechanism (device) 121 for maintaining and recovering the nozzle state of the recording head 24 is disposed in the non-printing area on one side of the carriage 23 in the scanning direction. . The maintenance / recovery mechanism 121 is a cap member for capping each nozzle surface 24a of the five recording heads 24, and includes one suction cap 122a that also serves as a moisture retention, and four moisture retention caps 122b to 122e. A wiper blade 124, which is a wiping member for wiping the nozzle surface 24a of the recording head 24, and an idle ejection receiver 125 for performing idle ejection are disposed.

  Further, an idle ejection receptacle 126 for performing idle ejection is disposed in the non-printing area on the other side of the carriage 23 in the scanning direction. Openings 127 a to 127 e are formed in the idle discharge receptacle 126.

  The sub-scanning conveyance unit 3 conveys the paper 5 that is a sheet material fed from below from the lower side by a conveyance roller 32 that is a driving roller for conveying the sheet 5 so as to face the image forming unit 2 while changing the conveyance direction by approximately 90 degrees. And an endless transport belt 31 laid between a tension roller and a driven roller 33 as a tension roller, and a charging roller 34 as a charging means to which an AC bias voltage as an alternating voltage is applied to charge the surface of the transport belt 31. A platen guide member 35 that guides the conveyance belt 31 in a region facing the image forming unit 2, and a first pressure roller (inlet pressure roller) that presses the sheet 5 toward the conveyance belt 31 at a position facing the conveyance roller 32. ) 36, and the sheet 5 is pressed against the platen guide member 35 between the conveyance roller 32 and the recording head 34 which is an image forming unit. 2 pressing roller (tip pressing roller) 37, and a separation claw 39 for separating the sheet 5 on which an image is formed from the transport belt 31 by the image forming unit 2.

  The transport belt 31 of the sub-scan transport unit 3 is rotated in the paper transport direction (sub-scan direction) in FIG. 2 by rotating the transport roller 32 from the sub-scan motor 131 through the timing belt 132 and the timing roller 133. It is configured to do.

  The paper feeding unit 4 is detachable from the apparatus main body 1 and separates the paper 5 in the paper feeding cassette 41 one by one from the paper feeding cassette 41 which is a storing means for stacking and storing a large number of papers 5. A sheet feeding roller 42 and a friction pad 43 for feeding out and a registration roller pair 44 for registering the sheet 5 to be fed are provided.

  The paper feed unit 4 includes a manual feed tray 46 for stacking and storing a large number of sheets 5, a manual feed roller 47 for feeding the sheets 5 from the manual feed tray 46 one by one, and the apparatus main body 1. On the lower side, an optional paper feed cassette and a vertical transport roller 48 for transporting the paper 5 fed from the duplex unit are provided. Members for feeding the paper 5 to the sub-scanning conveying unit 3 such as the paper feeding roller 42, the registration roller 44, the manual feeding roller 47, and the vertical conveying roller 48 are a paper feeding made of an HB type stepping motor via an electromagnetic clutch (not shown). The motor (drive means) 49 is rotationally driven.

  The paper discharge conveyance unit 6 includes a pair of paper discharge conveyance rollers 61 and 62 for conveying the paper 5 on which image formation has been performed, a paper discharge conveyance roller pair 63 and a paper discharge roller 64 for sending the paper 5 to the paper discharge tray 7. And.

  In the image forming apparatus configured as described above, the rotation amount of the conveyance roller 32 that drives the conveyance belt 31 is detected, and the sub-scanning motor 131 is driven and controlled according to the detected rotation amount, and an AC (not shown) is also illustrated. A positive and negative rectangular wave high voltage, which is an alternating voltage, is applied from the bias supply unit to the charging roller 34, whereby positive and negative charges are alternately band-shaped in the conveying direction of the conveying belt 31. And is charged with a predetermined charging width on the conveying belt 31 to generate an unequal electric field.

  Therefore, the conveyance belt in which an unequal electric field is generated by the sheet 5 being fed from the sheet feeding unit 4 and fed between the conveyance roller 32 and the pressing roller 36 to form positive and negative charges. When fed onto the paper 31, the paper 5 is instantly polarized according to the direction of the electric field, and is attracted onto the transport belt 31 by the electrostatic attraction force, and is transported as the transport belt 31 moves.

  Then, while the paper 5 is intermittently transported by the transport belt 31, recording liquid droplets are ejected from the recording head 24 onto the paper 5 to record (print) an image, and the front end of the paper 5 on which printing is performed The side is separated from the conveyance belt 31 by the separation claw 37 and sent to the paper discharge conveyance unit 6 by the conveyance roller 38.

  During printing (recording) standby, the carriage 23 is moved to the maintenance / recovery mechanism 121 side, and the nozzle surface of the recording head 24 is capped by the cap 122, and the nozzles are kept in a wet state. To prevent. Further, the recording liquid is sucked from the nozzle in a state where the recording head 24 is capped with the suction and moisture retention cap 122a, and a recovery operation for discharging the thickened recording liquid and bubbles is performed. Wiping is performed by the wiper blade 124 in order to clean and remove the ink adhering to the ink. In addition, a blank ejection operation is performed in which ink that is not related to printing is ejected toward the blank ejection receiver 125 before recording is started or during recording. Thereby, the stable ejection performance of the recording head 24 is maintained.

Next, a first embodiment of the present invention in this image forming apparatus will be described with reference to FIGS. FIG. 5 is an explanatory perspective view of the main part of the rear surface of the carriage, and FIG. 6 is an explanatory diagram of a linear scale used in this embodiment.
Here, as shown in FIG. 5, the linear scale 128 is formed by printing a scale 128b on a base member 128a made of PET or the like, and has a hole 128c at one end.

  On the other hand, a hook portion 201 which is a holding member capable of detachably holding one end portion of the linear scale 128 is provided on the linear scale regular fixing position side on the rear surface of the carriage 23. The holding member (hook portion) 201 is formed so that a hole portion 128 c provided at one end portion of the linear scale 128 can be locked.

  Further, a fixed holding member 210 is provided at a regular fixing position of the linear scale 128 to hold and fix one end of the linear scale 128 by locking the hole 128c.

  Therefore, when exchanging the linear scale 128, as shown in FIG. 7A, the hole portion 128c at one end of the linear scale 128 is locked and held by the hook portion 201, and then as shown in FIG. Next, the carriage 23 is moved in the direction of the arrow to a position close to the normal fixing position (the position of the fixing holding member 210), and then one end of the linear scale 128 is detached from the hook portion 201 and fixed as shown in FIG. The member 210 is fixedly held.

  As described above, the carriage has a holding member capable of detachably holding one end of the linear scale, and the carriage is moved while the one end of the linear scale is held by the holding member of the carriage when replacing the linear scale. In this configuration, one end of the linear scale is guided to the vicinity of the fixed position, so the linear scale is passed through the back side of the carriage, which has been performed by operators and service personnel, and the end of the linear scale is held by hand. In addition, it is not necessary to draw the linear scale to the proper fixed position while being careful not to touch the surrounding parts. When replacing the linear scale, replacement work such as human sebum adheres to the surface of the linear scale. It is possible to reduce the risk of occurrence of damage associated with.

  That is, the linear scale 128 passes through the encoder sensor 129 on the back surface of the carriage 23 and is suspended on the side plates 101F and 101R on both sides, and the guide rod 21 penetrates the carriage 23 and is held on the side plates 101F and 101R on both sides. Many operations are required to remove the carriage 23 when the linear scale 128 is replaced. Further, in order to replace the linear scale 128 without removing the carriage 23, it is necessary to pass the linear scale 128 under the guide rail 22 on the back side of the carriage 23, and the space between the side plates 101F and 101R is limited. Workability in space becomes extremely poor.

  In general, in order to replace the linear scale 128 without removing the carriage 23, the linear scale 128 is passed through the back surface of the carriage 23, and then the end of the linear scale 128 is moved and fixed to a normal fixing position by a human hand. However, the linear scale 128 is generally printed on a transparent PET material, and sebum such as fingers is likely to adhere to the surface of the linear scale 128. The linear scale 128 is a film-like member and has a thickness. Since it is thin, its waist is weak, and there is a problem that the surface is easily damaged by being folded during contact with the surrounding parts.

  If a reading error by the encoder sensor 129 occurs due to damage to the pattern (scale) on the surface of the linear scale 128, the positional accuracy of the carriage 23 cannot be correct, and an abnormal image is generated or maintained at the target position. Inconveniences such as liquid splashing and machine stoppage due to the inability to do so.

  Therefore, as in this embodiment, the carriage is provided with a holding member that holds one end of the linear scale, and the carriage is moved to the vicinity of the normal fixing position while the one end of the linear scale is held by the holding member of the carriage. By moving the linear scale to the regular fixed position at that stage, it is possible to reduce the possibility of damage to the surface of the linear scale.

  Further, by using a hook-shaped holding member as the holding member, one end of the linear scale can be easily held by the carriage.

Next, a second embodiment of the present invention in this image forming apparatus will be described with reference to FIG. FIG. 8 is an explanatory perspective view of the main part of the rear surface of the carriage.
Here, the holding member 202 provided on the carriage 23 has a slit portion 202 a into which one end portion of the linear scale 128 is fitted. The width of the slit portion 202a (slit width) is preferably set slightly narrower than the thickness of the linear scale 128. If the slit width is too narrow, damage to the linear scale 128 increases. However, when there is no pattern (scale 128b) at one end of the linear scale 128, the slit width can be made narrower. In this example, a linear scale 128 that does not have the hole 200 shown in FIG. 6 is used. Thus, by providing the slit portion in the holding member, the linear scale can be easily held by the carriage.

Next, a third embodiment of the present invention in this image forming apparatus will be described with reference to FIG. FIG. 9 is an explanatory front view of the holding member.
Here, the protective member 203 is attached to the slit portion 202a of the holding member 202 of the second embodiment. In this case, the slit width H is set smaller than “linear scale thickness Tl− (protective member thickness Th × 2)”. As the protective member 203, foamed sponge material, rubber, resin with low hardness, and the like are suitable.

  Thus, by providing a protective member in the slit portion, it is possible to eliminate damage to the surface of the linear scale when the linear scale is held.

Next, a fourth embodiment of the present invention in this image forming apparatus will be described with reference to FIG. FIG. 10 is an explanatory front view of the holding member.
Here, a clip-shaped holding member 204 formed integrally with the constituent members of the carriage 23 is provided. A general-purpose clip component can be fixed (for example, attached) to the carriage 23.

  Thus, by making the holding member into a clip shape, the linear scale can be easily held on the carriage.

Next, a fifth embodiment of the present invention in this image forming apparatus will be described with reference to FIG. FIG. 11 is an explanatory perspective view of the main part of the rear surface of the carriage.
Here, a moving member 205 is held on the rear surface of the carriage 23 by a plurality of (here, four) claw portions 206 which are guide members so as to be movable in the moving direction of the carriage 23. A holding member 206 (illustrated in the clip shape of FIG. 10) that holds one end portion is provided. Note that the movement guide mechanism of the moving member 205 is not limited to the claw portion, and may be configured of, for example, a shaft, a long hole, and a pin member.

  Thereby, as shown in FIG. 12A, the moving member 205 can be moved along the moving direction of the carriage 23 after holding one end of the linear scale 128 by the holding member 206.

  Thus, by providing the holding member not on the carriage but on the member that is movable with respect to the carriage and not on the carriage, it is not necessary to pass the carriage back to hold the linear scale on the holding member. Furthermore, damage to the linear scale can be reduced.

Next, a sixth embodiment of the present invention in this image forming apparatus will be described with reference to FIG. FIG. 13 is an explanatory plan view of a main part for explaining the embodiment.
Here, a main body side holding member 207 for locking and holding one end portion of the linear scale 128 is provided on the rear plate 101C of the apparatus main body located on the back side of the carriage 23.

  In this case, as shown in FIG. 13A, after holding one end portion of the linear scale 128 on the main body side holding member 207, the carriage 23 is moved in the direction of the arrow as shown in FIG. Thus, the linear scale 128 can be passed through the back side of the carriage 23. In this state, one end portion of the linear scale 128 is moved to the holding member 204 of the carriage 23 to be held.

  As described above, before the linear scale is held by the holding member provided on the carriage, it is once held on the main body side holding member separately provided on the apparatus main body, so that the carriage can be moved more easily by moving the carriage. The linear scale can be passed through.

Next, a seventh embodiment of the present invention in this image forming apparatus will be described with reference to FIGS. FIG. 14 is an explanatory perspective view of the main part of the rear surface of the carriage, and FIG. 15 is a rear view of the carriage.
Here, a plurality (three in this case) of holding members 204 and 208 are provided at both ends and the center of the carriage 23 in the moving direction. Here, the clip-shaped holding member 204 is used as a holding member for holding one end portion of the linear scale 128, but the holding member 208 holding the rear side from the one end portion is only required to hold the posture of the linear scale 128. A concave shape is used. Note that the holding member having a concave cross-section means that the holding member 208 forms a recess between the rear surface of the carriage 23 as in the present embodiment. Moreover, it can replace with the clip holding member 204, for example, can also use the holding member of the said each embodiment.

  In other words, if only one holding member is provided, the posture of the linear scale during linear scale conveyance due to carriage movement becomes unstable. By providing a plurality of holding members on the carriage in this way, the carriage The posture of the moving linear scale can be kept more stable.

Next, an eighth embodiment of the present invention in the image forming apparatus will be described with reference to FIG. FIG. 16 is a schematic explanatory diagram for explaining the embodiment.
Here, a hole 221 through which the linear scale 128 is passed is formed in the front plate 101F of the apparatus main body. As a result, when the linear scale 128 is held by the holding member of the carriage 23, the linear scale 128 can be drawn from the outside to the back side of the carriage 23 through the hole 221. That is, as shown in FIG. 17, when the front plate 101F of the apparatus main body does not have the hole 221, the carriage 23 is often located near the center of the movable range because of the workability of replacing the linear scale 128. The other end portion 128d opposite to the one end side held by the holding member 23 may come into contact with the side plate 101F and damage may occur, but by providing the hole portion 221 as in the present embodiment, The risk of such damage occurring can be reduced.

  In other words, when the linear scale is held by the carriage and the carriage is moved, the linear scale on the side that is not held is long, so it may come into contact with the side plate, etc. Thus, by providing the hole for exchanging the linear scale in the side plate, it is possible to prevent the linear scale from being damaged before the carriage is moved.

Next, a different example of the ninth embodiment of the present invention in the image forming apparatus will be described with reference to FIGS. 18 to 20 are enlarged explanatory views of hole portions of the side plates.
Here, a protective member is provided around the hole portion 221 through which the linear scale 128 provided in the front plate 101F of the apparatus main body in the eighth embodiment is passed, so that when the linear scale 128 is passed through the hole portion 221, or the carriage When the linear scale 128 is moved by the operation 23, the risk of damaging the linear scale 128 at the edge of the hole 221 is reduced.

  That is, in the first example shown in FIG. 18, the protection member 212 made of a sponge material such as urethane foam is attached to the edge (periphery) of the hole 221 formed in the square hole with an adhesive tape. In the second example shown in FIG. 19, a protection member 213 made of a general-purpose universal bush is attached to the edge (periphery) of the hole 221 formed in the square hole. In the third example shown in FIG. 20, a protective member 214 made of a general-purpose bush is attached to a hole 221 in which a round hole is formed. Commercially available bushes are often made of a material having high slidability such as nylon for the purpose of protecting a harness and are suitable as a protective member.

Next, a first embodiment of a replacement linear scale according to the present invention will be described with reference to FIG. FIG. 21 is an explanatory perspective view showing the replacement linear scale according to the embodiment together with the protective material.
The replacement linear scale 128 is covered with a bag-like protective material 231. As the material of the protective material 231, a material such as a film or paper that has a small thickness that hardly affects the pattern (scale) 128 b of the linear scale 128 and follows the deformation of the linear scale 128 is suitable.

  Thus, by covering the replacement linear scale with the bag-shaped protective material, it is possible to eliminate damage (damage due to sebum adhesion or breakage) to the surface of the linear scale.

Next, a second embodiment of the replacement linear scale according to the present invention will be described with reference to FIG. FIG. 22 is an explanatory perspective view showing the replacement linear scale according to the embodiment together with the protective material.
Here, a plurality of adhesive materials 232 are provided on the surface of the bag-shaped protective material 231 that covers the linear scale 128. Note that the adhesive 232 is preferably provided with tear paper. Thereby, the linear scale 128 can be once affixed to the rear plate 101C of the apparatus main body.

  In this way, after holding the linear scale together with the protective material on the apparatus main body by the adhesive material, the linear scale can be automatically extracted from the protective material by moving the carriage on which one end of the linear scale is held, Damage to the surface of the linear scale that occurs when the protective material is removed from the linear scale can be reduced.

  Here, the replacement method using the replacement linear scale of this embodiment will be described. The adhesive material 232 provided at least at the end of the bag-shaped protective material 231 covering the replacement linear scale 128 is attached to the rear plate of the apparatus main body. A step of fixing to 101C is performed, and then a step of holding one end of the replacement linear scale 128 on a holding member 201 (other holding member may be provided) provided on the carriage 23 on which the recording head 24 is mounted is performed. After that, the carriage 23 is moved to the fixed position side where one end of the linear scale 128 is fixed, and the linear scale 128 is extracted from the protective material 231. Finally, one end of the linear scale 128 is removed from the carriage 23, The fixed holding member 210 (see FIG. 7) at the fixed position is fixedly held.

  By performing such an exchange method, it is possible to reduce damage to the surface of the linear scale that occurs when the protective material is removed from the linear scale.

Next, a third embodiment of the replacement linear scale according to the present invention will be described with reference to FIGS. FIG. 23 is a perspective explanatory view showing the replacement linear scale according to the embodiment together with the protective material, and FIG. 24 is a perspective explanatory view of the state in which the protective material is similarly opened.
Here, as shown in FIG. 23, a bag-shaped protective material 233 that covers the entire linear scale 128 is used, and this protective material 233 is provided with an opening tape 234 that is opened along the circumferential direction on the inner surface of one end. When the linear scale 128 is replaced, as shown in FIG. 24, one end portion of the protective material 233 is opened by the opening tape 234 so that the linear scale 128 can be taken out. Thus, the linear scale 128 can be opened and used immediately before the replacement work.

  In other words, if the linear scale is simply wrapped with protective material, there is a risk of damage to the linear scale when the protective material is opened. The possibility of occurrence of damage can be reduced.

Next, a fourth embodiment of the replacement linear scale according to the present invention will be described with reference to FIGS. 25 and 26. FIG. 25 is a perspective explanatory view showing the replacement linear scale according to the embodiment together with a protective material, and FIG. 26 is a perspective explanatory view of the state in which the protective material is also opened.
Here, as shown in FIG. 25, a bag-like protective material 235 having openings at both ends covering the area where the scale 128b of the linear scale 128 is printed is used, and the protective agent 235 is opened along the longitudinal direction. An opening tape 236 is provided. When exchanging the linear scale 128, as shown in FIG. 26, after the exchanging operation of the linear scale 128 is completed, the opening tape 236 is pulled to remove the protective material 235 from the opened linear scale 128.

  In each of the above embodiments, the present invention has been described as an example in which the present invention is applied to an image forming apparatus as a multi-function machine having a plurality of functions. For example, a printer, a facsimile, a printing apparatus, a plotter, a copying apparatus, etc. The present invention can be similarly applied to a single-function image forming apparatus.

1 is a schematic configuration diagram illustrating an overall configuration of an image forming apparatus according to the present invention. It is plane explanatory drawing of the engine unit part of the same apparatus. It is a schematic front explanatory view of the engine unit. It is an outline perspective explanatory view of an engine unit part similarly. FIG. 2 is a perspective explanatory view of the main part of the rear surface of the carriage showing the first embodiment of the present invention in the image forming apparatus. It is explanatory drawing of the linear scale used in the embodiment. It is explanatory drawing similarly used for description of the exchange method of a linear scale. FIG. 6 is a perspective view of a main part of a rear surface of a carriage showing a second embodiment of the present invention in the image forming apparatus. It is front explanatory drawing of the holding member which shows 3rd Embodiment of this invention in the image forming apparatus. It is front explanatory drawing of the holding member which shows 4th Embodiment of this invention in the image forming apparatus. FIG. 10 is a perspective view of a main part of a rear surface of a carriage showing a fifth embodiment of the present invention in the image forming apparatus. It is explanatory drawing with which it uses for description of the linear scale replacement | exchange method in the same embodiment. It is principal part top explanatory drawing with which it uses for description of 6th Embodiment of this invention in the image forming apparatus. FIG. 10 is a perspective explanatory view of a main part of a rear surface of a carriage showing a seventh embodiment of the invention in the image forming apparatus. It is the rear view of a carriage similarly. FIG. 10 is a schematic explanatory diagram for explaining an eighth embodiment of the present invention in the image forming apparatus. It is typical explanatory drawing with which it uses for description of the comparative example of the embodiment. It is a principal part enlarged explanatory view of the hole of the side plate which shows the 1st example of 9th Embodiment of this invention in the image forming apparatus. It is a principal part expansion explanatory drawing of the hole of the side plate which shows the 2nd example of the embodiment. It is a principal part expanded explanatory view of the hole of the side plate which shows the 3rd example of the embodiment. It is a perspective explanatory view showing the exchange linear scale concerning a 1st embodiment of the exchange linear scale concerning the present invention with a protective material. It is a perspective explanatory view showing the exchange linear scale concerning a 2nd embodiment of the exchange linear scale concerning the present invention with a protection material. It is a perspective explanatory view showing the exchange linear scale concerning a 3rd embodiment of the exchange linear scale concerning the present invention with a protection material. It is a perspective explanatory view of the state where the protective material was similarly opened. It is a perspective explanatory view showing the exchange linear scale concerning a 4th embodiment of the exchange linear scale concerning the present invention with a protection material. It is a perspective explanatory view of the state where the protective material was similarly opened.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Apparatus main body 2 ... Image formation part 3 ... Sub-scanning conveyance part 4 ... Paper feed part 5 ... Paper (recording medium)
6 ... Paper discharge conveyance unit 7 ... Paper discharge tray (paper discharge unit)
DESCRIPTION OF SYMBOLS 11 ... Image reading part 23 ... Carriage 24 ... Recording head 27 ... Main scanning motor 28A ... Drive pulley 28B ... Driven pulley 29 ... Timing belt 128 ... Linear scale (encoder scale)
128: Encoder sensor 201, 202, 204, 208 ... Holding member 205 ... Moving member (slider)
206 ... Claw part (guide member)
207 ... Main body side holding member 210 ... Fixed holding member 211 ... Hole

Claims (13)

  In the image forming apparatus including a linear scale and a sensor constituting an encoder that generates a signal in response to movement of a carriage mounted with a recording head, a holding member capable of detachably holding one end of the linear scale on the carriage And when the linear scale is replaced, the carriage is moved in a state where one end portion of the linear scale is held by the holding member of the carriage to guide the one end portion of the linear scale to the vicinity of the fixed position. An image forming apparatus.   The image forming apparatus according to claim 1, wherein the holding member has a hook portion that locks a hole portion formed in one end portion of the linear scale.   2. The image forming apparatus according to claim 1, wherein the holding member has a slit portion into which one end portion of the linear scale is fitted.   4. The image forming apparatus according to claim 3, wherein a protective member is attached to the slit portion of the holding member.   The image forming apparatus according to claim 1, wherein the holding member has a clip portion that sandwiches one end portion of the linear scale.   The image forming apparatus according to claim 1, wherein the holding member is provided to be movable relative to the carriage.   The image forming apparatus according to claim 1, comprising a plurality of the holding members.   8. The image forming apparatus according to claim 7, wherein the holding members are provided at both ends of the carriage in the moving direction.   9. The image forming apparatus according to claim 8, wherein a holding member relatively distant from the fixed position of the linear scale among the plurality of holding members has a concave cross-sectional shape.   10. The image forming apparatus according to claim 1, wherein a side plate to which a guide member holding the carriage is movably provided has a hole through which the linear scale can pass. An image forming apparatus.   The image forming apparatus according to claim 10, wherein a protective member is provided on an inner peripheral surface of the hole through which the linear scale can pass.   12. The image forming apparatus according to claim 1, wherein the main body includes a main body side holding member that detachably holds one end of the linear scale. Fixing the adhesive material provided at the end of the bag-shaped protective material covering the replacement linear scale to the apparatus body;
A step of holding one end of the replacement linear scale on a holding member provided on a carriage on which a recording head is mounted;
Moving the carriage to a fixed position side for fixing one end of the replacement linear scale, and extracting the replacement linear scale from the protective material;
A linear scale exchanging method in an image forming apparatus, comprising:

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