JP3883336B2 - Image forming apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus in which a sheet feeding tray is attached to an apparatus main body. Specifically, the sheet feeding tray of the apparatus main body is opened to perform jam processing using a space generated by the movement of the sheet feeding tray. The present invention relates to such an image forming apparatus.
[0002]
[Prior art]
In recent years, image forming apparatuses such as electrophotographic copying machines, laser beam printers, facsimiles, and the like are loaded with transfer paper on which images have been recorded on one side again on the paper feed tray for the purpose of saving resources in consideration of the environment. There is a growing tendency to create images. Accordingly, the probability of non-feeding in the paper feeding unit of the image forming apparatus and paper jam in the paper feeding unit is remarkably increased due to an operator's inadequate loading of the transfer paper and curling of the transfer paper itself. As described above, when a paper jam occurs in the paper feeding unit of the image forming apparatus, the jam processing space is narrow. Therefore, in the conventional apparatus, it is common to take time for the jam processing, and the paper feeding tray is removed from the apparatus main body. There is a potential demand to secure an opening in a part of the cover member of the apparatus main body to facilitate the jam processing.
[0003]
However, if the paper feed tray can be removed, the jam processing is facilitated, but the operator may directly touch the moving parts such as paper feed rollers and transport members inside the device main unit, and electrical components such as motors and power supplies. However, there has been a problem in making it possible to remove the paper feed tray from the apparatus main body without taking appropriate measures against this.
Here, if covers are attached to prevent touching parts such as moving parts inside the device body, the number of parts will increase, resulting in an increase in cost, and the assembly and maintenance serviceability will be very poor. turn into. Therefore, when securing the jam processing space, the paper feed tray set detection mechanism that detects whether or not the paper feed tray has been completely set in the main body of the apparatus and the paper feed tray paper size detection mechanism are provided. There is a mechanism that is used as a lock mechanism and controls the image forming apparatus to be prohibited from starting when the paper feed tray is not completely set to ensure safety during jam processing.
[0004]
As an interlock mechanism that prohibits the image forming apparatus from starting at a predetermined time, an interlock mechanism that is interlocked with the opening of various cover members is known. For example, in Japanese Utility Model Registration No. 2514666, the interlock switch is turned off when the front cover is opened, and the image forming apparatus for the front cover can be stopped. Japanese Patent Laid-Open No. 8-152756 discloses a marking unit. Japanese Patent Laid-Open No. 6-273986 discloses a front portion of a unitized fixing device in which the interlock mechanism allows the cover member to be closed only when the cover member is completely mounted and the image forming apparatus can be driven. When the door is opened, an interlock switch is turned on via an interlocking member that interlocks with the door to hold the image forming apparatus in an inoperative state.
[0005]
[Problems to be solved by the invention]
As described above, in each interlock mechanism disclosed in Japanese Utility Model Registration No. 2514666, Japanese Patent Laid-Open No. 8-152756, and Japanese Patent Laid-Open No. 6-273986, the cover member and the like which are part of the image forming apparatus are completely closed. An interlock mechanism is provided that immediately stops the image forming apparatus when it is moved in the opening direction from the above state, but even if it can be applied as an interlock mechanism interlocked with the paper feed tray, in these cases, When the paper feed tray is pulled out when the transfer paper is replenished, the image forming apparatus is immediately held at the start stop. For this reason, even when an image forming operation is performed using another paper feed tray that is not being supplied with transfer paper, the start is stopped. Although this can ensure the safety of the operator when the paper feed tray is removed from the main body of the apparatus when a paper jam occurs, the productivity of the image forming apparatus is reduced, and in particular, the image forming apparatus with a multi-stage paper feed tray attached. Then the frequency is high and it is a problem.
[0006]
Furthermore, in the case of a conventional image forming apparatus in which an interlock switch is attached to the lid member side that forms a part of the exterior material instead of the paper feed tray, the lid member can be installed without forgetting to return the paper feed tray to the apparatus body. If it is closed, the start stop is canceled, and the image forming apparatus may malfunction to impair safety, which is also a problem.
Furthermore, in order to make it possible to remove the paper feed tray from the main body of the device, control is runaway when the interlock detection mechanism is also used as a paper feed tray set detection mechanism or a paper feed tray paper size detection mechanism. This is likely to cause problems in ensuring safety during jam processing.
[0007]
Based on the consideration of the above-described problems, the invention of claim 1 can easily remove the paper feed tray out of the apparatus only when the paper, that is, the opening / closing member is opened, and can perform jam processing after ensuring the safety of the operator. With the goal.
Claim 2 is intended to simplify the configuration.
According to the third aspect of the present invention, the paper feed tray can be easily taken out of the machine only when the paper, that is, the opening / closing member is opened, and the jam can be processed while ensuring the safety of the operator. Accordingly, it is an object of the present invention to prevent malfunction and safety of the image forming apparatus from being impaired.
[0008]
The object of the present invention is to simplify the configuration and reduce the number of parts.
Claim 5 is intended to prevent a decrease in productivity and improve operability.
A sixth object of the present invention is to make it possible to easily remove a paper feed tray from the apparatus main body side using a guide rail and to perform jam processing.
[0009]
[Means for Solving the Problems]
According to a first aspect of the present invention, in the image forming apparatus, the apparatus main body detachably accommodates the paper feed tray, and the opening / closing member constituting a part of the exterior material supported by the apparatus main body is provided with a safety device interlocked therewith. The image forming apparatus is switched between on and off, and a part of the paper feed tray and a part of the open / close member in the closed state interfere with each other when the paper feed tray is removed, and the safety device operates when the open / close member is open. It prevents interference when holding the forming device inactive.
Thus, when the opening / closing member is closed and the safety device holds the image forming apparatus in operation, a part of the sheet feeding tray interferes with a part of the opening / closing member and the sheet feeding tray is taken out of the apparatus. The safety device is not activated by simply pulling out the paper feed tray, and the paper feed tray can be removed when the safety device holds the image forming device inactive with the open / close member open. To do. For this reason, the paper feed tray can be easily taken out of the apparatus only when the opening / closing member is opened and the safety device is operated to secure the safety of the operator, and jamming and maintenance work can be easily performed.
[0010]
According to a second aspect of the present invention, in the image forming apparatus according to the first aspect, the safety device is an interlock switch that stops driving the image forming apparatus. As described above, an interlock switch is used as a safety device, and this can be switched by a paper feed tray so that the image forming apparatus can be switched to stop driving. Therefore, it is possible to simplify the apparatus and facilitate operator safety. It can be secured.
[0011]
According to a third aspect of the present invention, in the image forming apparatus according to the first or second aspect of the present invention, the image forming apparatus further comprises a paper feed tray attachment confirmation member that moves when the paper feed tray is attached to or detached from the apparatus main body. The paper feed tray mounting confirmation member that has reached the first position due to the removal of the tray interferes with a part of the opening / closing member when the opening / closing member is closed, and the paper tray mounting that has reached the second position due to the mounting of the paper feed tray The confirmation member does not interfere with a part of the opening / closing member during the closing operation of the opening / closing member.
In this way, the sheet feed tray mounting confirmation member that has reached the first position by removing the sheet feed tray interferes with a part of the opening / closing member during the closing operation of the opening / closing member, thereby preventing the closing operation. At the time of mounting, the sheet feeding tray mounting confirmation member that has reached the second position does not interfere with a part of the opening / closing member, and the closing operation of the opening / closing member can be permitted. For this reason, it is possible to easily remove the paper feed tray from the machine to ensure the safety of the operator when jamming, and in particular, close the open / close member without forgetting to return the paper feed tray to the main unit. Therefore, it is possible to reliably prevent the image forming apparatus from malfunctioning or impairing safety.
[0012]
According to a fourth aspect of the present invention, in the image forming apparatus according to the third aspect, a part of the opening / closing member that interferes with the paper feed tray mounting confirmation member, a part of the paper feed tray, and the paper feed tray are removed. A part of the opening / closing member that interferes at the same time is the same.
In this way, part of the opening / closing member is used both as a member that interferes with the paper feed tray and as a member that interferes with the paper feed tray mounting confirmation member, so that the number of parts and cost can be reduced.
[0013]
According to a fifth aspect of the present invention, in the image forming apparatus according to any one of the first to fourth aspects, the paper feed tray includes a plurality of stages, and at least one of the paper feed trays is formed to be removable from the apparatus main body. It has been done.
In this way, a plurality of paper feed trays can be provided and at least one can be removed from the apparatus main body. For this reason, the paper feed tray can be easily removed from the machine only when the paper, that is, the opening / closing member is opened, and the operator can use the space after removing the paper feed tray for jamming and maintenance work without any safety problems. Therefore, when the transfer paper is replenished, the image forming process can be continued using another paper feed tray in the set, and the productivity can be prevented from being lowered and the operability can be improved.
[0014]
According to a sixth aspect of the present invention, in the image forming apparatus according to any one of the first to fifth aspects, the paper feed tray is slidably attached to the apparatus main body via a guide rail, and the same. It is characterized by being detachably attached to the guide rail.
Thus, when the paper feed tray is removed from the guide rail, the interlock mechanism can stop the operation of the image forming apparatus, and the interlock mechanism performs image forming processing when the paper feed tray is pulled out when the transfer paper is replenished. Do not ban. For this reason, the operation of pulling out the paper feed tray to the outside is further facilitated, and jam handling and maintenance work can be performed easily and safely.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a laser beam printer as an image forming apparatus to which the present invention is applied.
This laser beam printer (hereinafter simply referred to as a printer) 1 has two paper feed units 2 disposed below the apparatus main body 101, an image forming unit 3 and a fixing device 4 disposed above it, and above that. A gate 7 is provided for switching operation so that the fixed transfer paper is discharged to the discharge trays 5 and 6.
[0016]
The image forming unit 3 forms a copy of an original image by a known electrophotographic image forming process. The image forming unit 3 includes a photosensitive drum 8, and an image writing device 9, a developing device 11, and the like around the photosensitive drum. A cleaning device (not shown) and a transfer separation device 12 are provided. Further, the apparatus main body 101 is formed with a conveyance section 13 extending from below to above, and the conveyance section conveys the paper in the paper feeding section 2 to the photosensitive drum 8 side. The drive actuator that is not connected is connected to the control unit 10 (see FIG. 2).
[0017]
The image writing device 9 irradiates the photosensitive drum 8 with laser light to form an electrostatic latent image. The developing device 11 supplies toner to the electrostatic latent image on the photosensitive drum 8 to form a toner image. The conveyance unit 13 includes a registration roller pair 14, which aligns the leading edge of the transfer paper from the paper supply unit 2 in synchronization with the rotation of the photosensitive drum 8 and then has the same speed as the peripheral speed of the photosensitive drum 8. Transport by. The transfer / separation device 12 includes transfer and separation chargers (not shown), and transfers the toner image onto the transfer paper from the registration roller pair 14 and conveys it to the fixing device 4. The fixing device 4 melts and presses the toner image on the transfer paper and fixes it. The gate 7 switches so as to secure a conveyance path on the discharge roller pair 15 side when discharging the transfer paper image from the fixing device 4 downward, drives the discharge roller pair 15, and discharges the transfer roller pair 16 side when discharging upward. In order to secure the conveying path, the discharge roller pair 16 is driven.
[0018]
The paper feed unit 2 is arranged at the top and bottom, and includes first and second paper feed units 17 and 18 that accommodate sheets of two sizes, here A4 and B4. Here, the first and second paper feeding units 17 and 18 are attached to the apparatus main body 101 so as to be slidable within a predetermined tray sliding width L (see FIG. 2). Here, the first and second paper feeding units 17 and 18 have substantially the same configuration, and the upper first paper feeding unit 17 will be mainly described here. The first sheet feeding unit 17 is accommodated in a portion facing the conveying unit 13 in a tray accommodating space E provided on the lower side of the apparatus main body 101. As shown in FIG. 2, the tray accommodating space E is covered with a vertical frame 19 provided in four corners and an outer plate 20 with an inner wall integrally joined thereto, and is opened on the lower side and the right side in FIG. 2. Is formed so that it can be opened and closed by a paper feed tray 22 and a cover 30 described later.
[0019]
As shown in FIG. 4, the cover 30 has a horizontally long rectangular lid shape, and pivot pins 38 project from the lower ends of both ends in the longitudinal direction, and are pivoted to a pair of vertical frames 19 on the right side of the apparatus main body 101. By wearing it, it is pivotally supported by the closed position U0 (refer FIG. 2) and the open position U1 so that opening and closing operation is possible. The cover 30 is formed with four upper, lower, left, and right mounting holes 39 in the center of the front side wall, which is the inner side wall, and magnet pieces 40 that adsorb the cover 30 to the conveyance path guide 44 on the vertical frame 19 side in the vicinity of the left and right ends. Install. Further, the cover 30 is provided with an actuator piece 42 for switching the interlock switch 41 (see FIG. 2) on the left end side in FIG. 4, and two stoppers 31 and 43 as a part of the opening / closing member on the right end side. To project.
[0020]
As shown in FIG. 2, the interlock switch 41 is supported by the conveyance path guide 44 on the apparatus main body 101 side, and is turned off when the cover 30 is switched from the closed position U0 to the open position U1. A start prohibition signal is output to. A conveyance roller r5 (see FIG. 2) is pivotally attached to the mounting hole 39, and a grip roller r4 (see FIG. 2) that rotates in contact with the conveyance roller guide 44 is also pivotally attached to the opposite side of the conveyance path guide 44. .
[0021]
As shown in FIGS. 2 and 3, the first paper feed unit 17 is formed by a rail frame 21 supported by the apparatus main body 101 and a paper feed tray 22 detachably mounted on the rail frame 21. . The rail frame 21 is a front support member that integrally couples the left and right guide rails 23 and 24 composed of the outer rails 231 and 241 and the inner rails 232 and 242 slidably fitted thereinto, and the front ends of the left and right inner rails 232 and 242. 25 and left and right rear support members 26 and 27 that are separated and integrally coupled to the rear end. As shown in FIG. 2, the left and right outer rails 231 and 241 are respectively fixed to the front and back vertical frames 19, and in particular, the right front and back vertical frames 19 are respectively provided with auxiliary brackets 32 and 33, respectively. Are combined. The left and right outer rails 231 and 241 and the inner rails 232 and 242 (shown only on the left side in FIG. 6) are fitted with a plurality of rollers q between the respective upper and lower bent flanges, whereby the inner rails 232 and 242 side The sliding resistance is reduced. The rail frame 21 constitutes a mounting table on which the paper feed tray 22 is detachably mounted by the front support member 25 and the left and right rear support members 26 and 27 integrally coupled thereto. For this reason, the front support member 25 forms a tray receiving portion a having a concave portion at the center and an upward surface at the left and right ends. In particular, the left and right tray receiving portions a are provided with pins 28 extending upward. The left and right rear support members 26 and 27 form a tray receiving portion a that forms an upward surface, and a pin 28 that extends upward is projected from the rear left tray receiving portion a.
[0022]
The paper feed tray 22 is formed by a tray main portion 221 having a substantially rectangular dish shape, and a front cover 222 that is integrally connected to the front side of the main portion. In some cases, the tray main portion 221 and the front cover 222 may be integrally formed. In this case, the structure can be simplified.
The front cover 222 has a rectangular long plate shape, a handle portion h is formed on the front side surface thereof, and a pair of attachment pieces d are formed on the back side surface so as to protrude rearward. A pair of attachment pieces d and a later-described central coupling portion c of the tray main portion 221 are bolted through bolt holes n and integrally coupled.
The tray main portion 221 has a plurality of positioning guide pieces g projecting on the central low wall, and an A4 transfer paper (not shown) is placed on a portion surrounded by the guide pieces g, and is placed on the right side. It forms so that it may send out to the conveyance part 13 side.
[0023]
The tray main portion 221 is formed with connecting flange portions b extending horizontally outward from the upper edge portions of the left and right corners of the front and rear side walls, and mounted on the tray receiving portion a on the rail frame 21 side where these lower surfaces face each other. It is formed so that it can be placed. Further, the central portion of the upper edge portion of the front side wall of the tray main portion 221 extends inward to form a central connecting portion c, thereby connecting the left and right connecting flange portions b to enhance the rigidity on the near side of the tray. In addition, a hole i is formed that allows the mounting piece d of the front cover 222 to be bolted.
[0024]
The right side wall w1 of the tray main portion 221 is formed of a vertically-oriented thin plate, and the upper end faces a first separation paper feeding portion R1 described later. From the upper end side outer wall surface of the right side wall w1, a horizontally long plate-like pressing portion G that protrudes in the vertical width direction Y, which is the pulling direction, protrudes and is formed. Further, an interference portion Q is formed that extends a predetermined amount backward from the connecting flange portion b on the right rear side of the tray main portion 221 and then bends and extends upward. The interference part Q is formed so as to be able to come into contact with a stopper 31 that forms part of the cover 30.
[0025]
As shown in FIGS. 2 and 6, the pressing portion G of the right side wall w <b> 1 of the tray main portion 221 is formed so as to be able to come into contact with the paper feed tray mounting confirmation member 34. It is pivotally attached to the vertical frame 19 on the front right side via an L-shaped bracket 35. As shown in FIG. 5, the L-shaped bracket 35 on which the paper feed tray mounting confirmation member 34 is pivotally provided has a pin 36 protruding from the main body, and a coil portion of a winding spring 37 is inserted into the pin 36. The base end portion 341 of the paper feed tray mounting confirmation member 34 is pivotally attached. A main portion 342 that contacts the pressing portion G extends from the base end portion 341, and a stopper piece portion 343 extends from one side edge so as to protrude from the upper surface of the main portion 342. As shown in FIG. 7A, the contact paper feed tray mounting confirmation member 34 is urged upward by a helical spring 37, and the paper feed tray 22 slides within the tray sliding width L. During this time, the second position S2 in contact with the pressing portion G is held. When the pressing portion G is removed, as shown in FIG. 7B, the stopper portion 343 is formed to be switched and held at the first position S <b> 1 that contacts the vertical frame 19. The The first position S1 functions to prevent the main portion 342 and the stopper 31 of the cover member 30 from interfering with each other and prevent the cover member 30 from rotating from the open position U0 toward the closed position U1.
[0026]
In FIG. 3, a state in which the long holes 45 in the lateral width direction X of the apparatus main body 101 can be inserted into the left and right pins 28 of the front support member 25 on the left and right sides of the connection flange portion b of the paper feed tray 22. Formed with. Further, a long hole 46 that is long in the vertical width direction Y is formed on the right side of the rear side so that the pin 28 of the rear support member 27 can be inserted. As described above, since the pin 28 is inserted into the elongated hole 46, the detachability of the paper feed tray 22 with respect to the rail frame 21 is improved. Moreover, when the four connecting flange portions b of the tray main portion 221 are placed on the tray receiving portion a of the rail frame 21, the two long holes 29 extending in the lateral width direction X fit the left and right pins 28. The shift of the paper feed tray 22 in the vertical width direction Y is regulated, and the long hole 46 in the vertical width direction Y is fitted with the pin 28, whereby the deviation of the paper feed tray 22 in the horizontal width direction X can be regulated. Due to such a configuration, it is easy to position the paper feed tray 22 on the rail frame 21, and it is very easy to pull it out from the rail frame 21 and to take it out of the machine.
[0027]
Although the first paper feeding unit 17 has been described here, the position of the positioning guide piece g disposed on the lower central wall is also the size of the transfer paper compared to the second paper feeding unit 17 in the second paper feeding unit 18. Except for the difference, it is formed in the same manner, and redundant description is omitted here.
The first and second sheet feeding units 17 and 18 constituting the sheet feeding unit 13 each include a first separation sheet feeding unit R1 having the same configuration. The first separation sheet feeding unit R1 cooperates with the calling roller r1 for turning the uppermost sheet in a state where it can be rolled, the sheet feeding roller r2 for feeding the uppermost sheet to the conveyance path 47 side, and the sheet feeding roller r2. It is composed of a reverse roller r3 that rolls a bundle and regulates the repeated feeding. Further, the sheet fed from the first separation sheet feeding portion R1 is sandwiched between the grip roller r4 and the conveyance roller r5, and the leading end thereof is directed to the conveyance path 47 side. The first separation sheet feeding unit R1 of the sheet feeding unit 2 is driven and controlled by the control unit 10.
[0028]
When the first separation sheet feeding unit R1 of the first and second sheet feeding units 17 and 18 is selectively driven by the control unit 10, the uppermost sheet of the stacked sheet bundle is sequentially sent to the conveyance path 47. To do. The conveyance path 47 drives each conveyance roller r <b> 5 to convey the sheet in the vertical direction and conveys the sheet to the entrance of the registration roller pair 14. The registration roller pair 14 is driven and controlled by the control unit 10 via a drive motor (not shown).
Such a printer 1 is instructed selectively by an operation unit (not shown) in an image forming mode, and starts an image forming operation in response to a start command. Here, the image forming unit 3 forms a copy of the original image by a known electrophotographic image forming process, and the image writing device 9 forms an electrostatic latent image on the photosensitive drum 8 and responds accordingly. The developing device 11 forms a toner image, and in conjunction with the formation of the toner image, for example, A4 transfer paper (not shown) is sent from the first paper feed unit 17 to the conveyance path 47 by the conveyance unit 13. Then, the transfer paper is aligned by the registration roller pair 14 so as to be synchronized with the rotation of the photosensitive drum 8, and is conveyed at the same speed as the peripheral speed of the photosensitive drum 11, and reaches the transfer separation device 12. The toner image is transferred to transfer paper. The transfer paper on which the toner image has been formed passes through the fixing device 4 and is fixed. Then, the transfer paper reaches the gate 7, and when the transfer paper image is discharged downward, the discharge roller pair 15 side is used. At the same time, the gate 7 is switched so as to selectively eject paper onto the paper ejection trays 5 and 6.
[0029]
When a transfer paper is transported by the transport unit 13 during such image formation, if a paper jam occurs on the transport path 47, the control unit 10 stops the image forming operation and displays a paper jam. At this time, the operator pulls out, for example, the paper feed tray 22 from the storage position P0 to the open position P1 (indicated by a two-dot chain line in FIG. 2) according to the paper jam display, and the stopper 31 of the cover 30 at the closed position U0 Abut. Therefore, the cover 30 is further opened to the open position U1, the interference state between the stopper 31 and the interference portion Q is released, and then the paper feed tray 22 is lifted from the rail frame 21 and pulled upward. In this case, by opening the cover 30 to the open position U <b> 1, the actuator piece 42 moves, the interlock switch 41 is turned on, and a start prohibition signal is output to the control unit 10. Therefore, the control unit 10 functions as a safety device that reliably stops the image forming operation until the interlock switch 41 is turned off again.
[0030]
During this time, the opening covered by the paper feed tray 22 leaves the rail frame 21 but is largely opened, and it is possible to easily perform jam processing for removing a paper jam on the conveyance path 47 by using the space that follows. . Even if the control is erroneously returned to the normal operation due to a change in the situation such as the paper jam being released during the jam processing, the cover 30 is surely returned to the closed position P0 until the interlock switch 41 is turned on. The restart of the image forming process can be prevented, and the jam process can be performed safely.
[0031]
Further, if the paper feed tray 22 is not returned to the rail frame 21 and returned to the storage position P0, the paper feed tray mounting confirmation member 34 continues to be held at the first position S1 that interferes with the stopper 31, and the cover 30 is opened. It is prevented from closing from U1 to the closed position U0, and the interlock switch 41 continues to be turned off. For this reason, the cover 30 is closed without forgetting to return the paper feed tray 22 to the apparatus main body 101, which can reliably prevent the printer 1 from being restarted accidentally and impairing safety, and safely jamming is performed. I can do it.
[0032]
Further, when the printer 1 is normally used, for example, it is assumed that A4 paper is insufficient, a paper detection mechanism (not shown) of the paper feed tray 22 is activated, and the image forming process is stopped. At this time, the operator pulls out the paper feed tray 22 from the storage position P0 to the open position P1, and then replenishes A4 paper. During this paper replenishment operation, the interlock switch 41 is kept on, and the image forming operation using the second paper supply unit 18 containing B5 size paper other than B4 can be easily performed. , Productivity can be prevented and operability can be improved.
Further, the printer 1 of FIG. 1 can function as a member that interferes with the paper feed tray 22 or a member that interferes with the paper feed tray mounting confirmation member 34 by using the stopper 31 of the cover 30 as a part of the opening / closing member. In this respect, the number of parts and the cost can be reduced. Note that, similarly to the stopper 31 for the first paper feed unit 17, the stopper 43 for the second paper feed unit 18 also functions, and the same effect can be obtained.
[0033]
The paper feed unit 2 of the printer 1 in FIG. 1 has the first and second paper feed units 17 and 18 in two stages. However, the present invention is applied to an image forming apparatus having a multi-stage paper feed unit. In addition, even if these three or more stages are provided, if there is only one cover 30 as an opening / closing member, only one interlock switch 41 can be used, which also simplifies the apparatus. I can plan. In an image forming apparatus having a multi-stage sheet feeding unit, in some cases, two or more opening / closing members such as a cover 30 and two or more interlock switches are provided, and the plurality of interlock switches are connected. An AND circuit may be formed by serial connection, and the restart of the printer may be prohibited while the circuit is turned off. In this case, the same effect as the printer 1 of FIG. 1 can be obtained.
[0034]
Further, the paper feed tray 22 of FIG. 1 is detachably attached to the rail frame 21, but in some cases, the rail frame 21 can be eliminated and the paper feed tray can be slid into a guide groove (not shown) of the apparatus main body. May be adopted, and a configuration in which the paper feed tray mounting confirmation member 34 is disposed in the vicinity of the guide groove may be employed. In this case, the apparatus can be simplified.
Further, the safety device is configured by the control unit 10 and the interlock switch 41. However, in some cases, a photo sensor (not shown) may be substituted for the interlock switch that is the limit switch here. Also, the same effects as those of the image forming apparatus of FIG. 1 can be obtained.
[0035]
Although the present invention has been described in detail with reference to the illustrated embodiments, the present invention is not limited to the above-described printer, but can be applied to other facsimiles, electrophotographic copying machines, and the like, and the same effects can be obtained. .
[0036]
【The invention's effect】
According to the first aspect of the present invention, a part of the paper feed tray and a part of the opening / closing member interfere with each other in a timely manner, and the safety device does not operate by a simple operation of pulling out the paper feed tray. Only when the safety device is operated by opening the paper feed tray, the paper feed tray can be easily taken out of the apparatus to ensure the safety of the operator, and the jam processing and maintenance work can be facilitated.
[0037]
According to the invention of claim 2, since the interlock switch is used as the safety device and is switched by the paper feed tray, the device can be simplified and the safety of the operator can be easily secured.
According to the third aspect of the present invention, a part of the paper feed tray and a part of the opening / closing member interfere with each other in a timely manner, and the feed is switched to the first position and the second position in conjunction with the attachment / detachment of the paper feed tray. Since a paper tray installation confirmation member is provided, it is possible to easily remove the paper feed tray from the machine and secure the operator's safety when handling the jam. Thus, it is possible to reliably prevent the image forming apparatus from malfunctioning or impairing safety.
[0038]
According to the fourth aspect of the present invention, part of the opening / closing member is used both as a member that interferes with the paper feed tray and as a member that interferes with the paper feed tray mounting confirmation member, so that the number of parts and cost can be reduced.
[0039]
According to the invention of claim 5, a plurality of paper feed trays are provided, and the paper feed tray is easily taken out from the apparatus only when the paper, that is, the opening / closing member is opened, and the space after the paper feed tray is removed is used. The operator can easily and safely perform jam processing and maintenance work without any safety problems, and can continue image forming processing using other paper feed trays when replenishing transfer paper, preventing a drop in productivity. The operability can be improved.
[0040]
According to the sixth aspect of the present invention, since the paper feed tray can be removed from the apparatus main body side using the guide rail, it is easier to take out the paper feed tray to the outside of the apparatus, and jam processing and maintenance work are facilitated. It can be done safely.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a printer as an image forming apparatus to which the present invention is applied.
FIG. 2 is a schematic plan cross-sectional view of a main part of the printer of FIG.
3 is an exploded perspective view of a paper feed tray and a rail frame used in the printer of FIG. 1. FIG.
4 is a perspective view of a cover used in the printer of FIG. 1. FIG.
5 is an exploded perspective view of a paper feed tray mounting confirmation member used in the printer of FIG. 1. FIG.
6 is an enlarged cutaway cross-sectional view of a coupling portion between a paper feed tray and a guide rail of the printer of FIG.
7A and 7B are operation explanatory views of a paper feed tray mounting confirmation member used in the printer of FIG. 1, in which FIG. 7A is a side view of a paper feeding tray mounting confirmation member at a second position, and FIG. The side view of a paper tray mounting | wearing confirmation member is shown.
[Explanation of symbols]
1 Printer
10 Control unit
101 Main unit
22 Paper tray
30 cover
31 Stopper
34 Feeding tray installation confirmation member
41 Interlock switch
42 Actuator piece
G Pressing part
Q Interference part

Claims (6)

In the image forming apparatus,
The apparatus main body is detachably mounted with a paper feed tray, and an opening / closing member that forms a part of the exterior material supported by the apparatus main body switches the image forming apparatus between the on and off states by a safety device that is linked thereto. A part of the paper tray and a part of the open / close member in the closed state interfere when the paper feed tray is removed, and do not interfere when the safety device holds the image forming apparatus in an inoperative state when the open / close member is open. An image forming apparatus. 2. The image forming apparatus according to claim 1, wherein the safety device is an interlock switch that stops driving the image forming apparatus. The image forming apparatus according to claim 1, wherein:
A paper feed tray mounting confirmation member that is switched when the paper tray is attached to or detached from the apparatus main body is provided, and the paper feed tray mounting confirmation member that has reached the first position by removing the paper feed tray is a part of the opening / closing member. And the sheet feeding tray mounting confirmation member that has reached the second position by mounting of the sheet feeding tray does not interfere with the part of the opening / closing member during the closing operation of the opening / closing member. Image forming apparatus. The image forming apparatus according to claim 3.
A part of the open / close member that interferes with the paper feed tray mounting confirmation member and a part of the open / close member that interferes when the paper feed tray is removed are the same part. An image forming apparatus. 5. The image forming apparatus according to claim 1, wherein the sheet feeding tray includes a plurality of stages, and at least one of the sheet feeding trays is formed to be detachable from the apparatus main body. Forming equipment. 6. The image forming apparatus according to claim 1, wherein the paper feed tray is slidably attached to the apparatus main body via a guide rail and is detachably attached to the guide rail. An image forming apparatus.

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