JP2009042721A - Image forming apparatus and bumper mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus which is capable of excellently performing the opening and closing operation of an upper unit which can be rotated with respect to an apparatus main body and has a slide mechanism and to provide a bumper used for the image forming apparatus. <P>SOLUTION: The image forming apparatus is provided with: an image forming means 1,000 which forms an image; the upper unit 1,500 which can rotate around a first shaft 1,300 with respect to the image forming means 1,000; a slide portion 1,800 which is provided in the upper unit 1,500 and can slide in a direction perpendicular to the axial direction of the first shaft 1,300; and an energizing means which applies an energizing force in a direction where the upper unit 1,500 is opened with respect to the image forming means 1,000 to the upper unit 1,500. Further, the image forming apparatus is provided with an energizing force changing means for performing change so that the energizing force may be decreased according to the fact that the slide portion 1,800 slides with respect to the upper unit 1,500 in a direction where the slide portion 1,800 goes toward a side where the first shaft 1,300 is attached from a side opposite to the side where the first shaft 1,300 of the upper unit 1,500 is attached. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming apparatus such as a copying machine, a facsimile machine, and a printer, and a buffer mechanism for an opening / closing member provided in the image forming apparatus.

  This type of image forming apparatus is a small-sized or general-use one that can open the upper cover of the apparatus body to expose the interior of the apparatus body when trouble such as toner cartridge replacement or paper jam occurs. Is known (Patent Document 1, etc.). In many cases, the upper cover is provided with a heavy object such as a scanner, as in the image forming apparatus described in Japanese Patent Application Laid-Open No. H10-228707.

  In order to make it easier for the operator to operate when opening the upper cover, or to prevent injury or damage to mounted parts due to sudden cover closing due to the weight of the upper cover when closing the upper cover, etc. For this purpose, a damper, which is a buffer mechanism, is generally provided on the rotating shaft portion of the upper cover. By applying an appropriate force to the upper cover in the direction of opening the upper cover with this damper, it is possible to reduce the force required by the operator when opening the upper cover, and to reduce impact and avoid danger when closing the upper cover. It becomes. However, when a heavy object such as a scanner is provided on the upper cover, it is necessary to increase the force of the damper in the opening direction of the upper cover, so a larger damper is required and the buffer mechanism is expensive. It was.

  In the image forming apparatus described in Patent Document 2, an opening / closing body that is rotatable about a rotation axis with respect to the apparatus main body is provided. The opening / closing body is provided with an arm whose one end is attached to the opening / closing body so as to be rotatable about a rotation shaft provided on the opening / closing body and whose other end is guided along the guide surface of the apparatus body. It has been. The rotating shaft provided in the opening / closing body is provided with a torsion spring that applies the other end of the arm in a direction in which the other end is pressed against the guide surface. When the arm presses the guide surface, the opening / closing body opens. It is configured to obtain a biasing force. As a result, an urging force in the opening direction is applied to the opening / closing body when the arm presses the guide surface, so that the force required when the operator opens the opening / closing body with respect to the apparatus main body can be reduced. . Further, when the opening / closing body is closed with respect to the apparatus main body, the force applied in the closing direction due to the weight of the opening / closing body can be reduced by the urging force, so that the momentum at which the opening / closing body is closed can be reduced.

JP 2005-167801 A JP 2002-361975 A

  However, the buffer mechanism proposed in Patent Document 2 has the following problems in the image forming apparatus described in Japanese Patent Application No. 2007-15090 (hereinafter referred to as the prior application) proposed by the applicant of the present application.

  In the image forming apparatus described in the above-mentioned prior application, an image is formed between an upper cover that is rotatable with respect to the apparatus main body and a scanner that is supported by the upper cover with a space above the upper cover. A sheet placing portion for placing the sheet is provided. As described above, when the space between the upper cover and the scanner is used as the sheet placing portion, the scanner is almost directly above the sheet placing portion for reasons such as compactness of the apparatus. For this reason, the sheet take-out performance from the sheet placement section and the sheet visibility of the sheet placement section are deteriorated. Therefore, in the image forming apparatus described in the above-mentioned prior application, the scanner is configured to be slidable with respect to the upper cover, and the scanner is slid in a direction in which a part of the upper part of the sheet placement unit is opened. This reduces the deterioration of takeout and sheet visibility.

  However, if the scanner is slidable with respect to the upper cover, the center of gravity of the scanner is displaced with respect to the upper cover as the scanner slides. For example, when the scanner is slid to the rear of the apparatus provided with the rotation axis of the upper cover, the center of gravity of the scanner with respect to the upper cover is also displaced to the rear of the apparatus. Therefore, in the buffer mechanism for opening and closing the upper cover that is optimized before the scanner slides, the center of gravity of the scanner is displaced to the rear of the device, so that the device from the front of the device is centered around the rotation shaft provided at the rear of the device. A problem arises in that the urging force for applying the upper cover in the opening direction that rotates backward becomes excessive, and the upper cover that supports the scanner falls down vigorously backward. In particular, it becomes noticeable when the upper cover is opened and the center of gravity of the scanner exceeds the rotation axis. Also, when closing the upper cover, the center of gravity of the scanner is displaced toward the rear of the device in addition to the biasing force applied to the upper cover by the buffer mechanism in the opening direction. The problem will be worsened.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an image forming apparatus capable of satisfactorily opening and closing an upper unit having a slide mechanism that is rotatable with respect to the apparatus main body. It is another object of the present invention to provide a buffer mechanism used in the image forming apparatus.

In order to achieve the above object, the invention of claim 1 is directed to an image forming means for forming an image, an upper unit rotatable about the first axis with respect to the image forming means, and the upper unit. A provided slide portion that is slidable in a direction perpendicular to the axial direction of the first shaft, and an attaching force that applies an urging force to the image forming means in the direction in which the upper unit opens. In the image forming apparatus having the biasing means, the slide portion is moved in the direction from the opposite side of the upper unit to the side to which the first shaft is attached toward the side to which the first shaft is attached. It is characterized by comprising urging force changing means for changing the urging force applied from the urging means to the upper unit as the unit slides.
According to a second aspect of the present invention, in the image forming apparatus of the first aspect, an arm member that is rotatable with respect to the upper unit about a second axis provided in the upper unit; A guide portion provided in the image forming means for guiding an end portion that is not pivotally supported along the guide surface; and a torque generating member that applies a rotational biasing force to the arm member. The urging means is configured to apply an urging force in the opening direction to the upper unit when the arm member presses the guide surface with the rotational urging force of the first unit. The biasing force is such that the rotational biasing force decreases as the slide portion slides relative to the upper unit in a direction from the side opposite to the side to which the first shaft is attached to the side to which the first shaft is attached. That the means of change is configured It is an.
According to a third aspect of the present invention, in the image forming apparatus of the second aspect, the torque generating member is a torsion spring having one end locked to the upper unit portion and the other end locked to the arm member. A rack arranged in the sliding direction of the sliding portion and a rotating member having a gear that meshes with the rack are provided on the circumference, and the rotating member is used as the unit portion that locks the one end. The urging force changing means is configured by arranging the torsion spring in a winding direction such that the rotational urging force becomes smaller as the upper unit slides.
According to a fourth aspect of the present invention, in the image forming apparatus of the second aspect, the torque generating means comprising the torque generating member and the rotational biasing force changing means includes a cam portion provided in a thrust direction of the arm member. And an opposing member having a cam portion facing the cam portion of the arm member from a thrust direction of the rotation shaft of the arm member, and an elastic member that presses the opposing member in the arm member direction. It is.
According to a fifth aspect of the present invention, in the image forming apparatus according to the second aspect, the torque generating means comprising the urging means and the rotational urging force changing means is a projection provided in the thrust direction of the arm member. The arm member comprises a facing member having a cam portion facing from the thrust direction of the rotation shaft of the arm member to the protruding portion of the arm member, and an elastic member that presses the facing member in the arm member direction. It is.
According to a sixth aspect of the present invention, in the image forming apparatus of the second aspect, the torque generating means comprising the urging means and the rotational urging force changing means includes a cam portion provided in the thrust direction of the arm member. The arm member includes a facing member having a protruding portion facing the cam portion of the arm member from a thrust direction of the rotation shaft of the arm member, and an elastic member that presses the facing member in the arm member direction. It is.
According to a seventh aspect of the invention, in the image forming apparatus of the first, second, third, fourth, fifth or sixth aspect, the upper unit is provided with an image reading means for reading image information of a document. is there.
According to an eighth aspect of the present invention, in the image forming apparatus according to the first, second, third, fourth, fifth, sixth or seventh aspect, the upper unit has an image formed in a gap provided below the slide portion. A sheet placement portion for placing the sheet member is provided.
According to a ninth aspect of the present invention, in the image forming apparatus according to the first, second, third, fourth, fifth, sixth, seventh, or eighth aspect, the upper unit is provided with an elastic member that presses the slide portion forward of the slide. It is characterized by.
According to a tenth aspect of the present invention, in the image forming apparatus according to the first, second, third, fourth, fifth, sixth, seventh, eighth, or ninth aspect, the slide portion is fixed so as not to move with respect to the upper unit. When a slide lock switch is provided, and the slide part is fixed to the upper unit by the slide lock switch, a rack arranged in the slide direction of the slide part provided in the slide part; The rack and the gear are configured to engage with each other when the sliding portion is released and the gear provided to the rotation biasing force changing means is not engaged. .
Further, the invention of claim 11 is directed to a lower unit and a direction perpendicular to the first axial direction that is rotatable with respect to the lower unit about a first axis provided in the lower unit. In the buffer mechanism provided between the sliding unit and the upper unit provided with a sliding part, the upper unit has a biasing means for imparting a biasing force to the lower unit in the opening direction of the upper unit. As the slide portion slides relative to the upper unit in a direction from the opposite side of the upper unit to the side to which the first shaft is attached, An urging force changing unit that changes the urging force applied to the upper unit from the urging unit is provided.

  In the present invention, as the slide portion slides with respect to the upper unit in the direction from the side opposite to the side on which the first shaft of the upper unit is attached to the side on which the first shaft is attached, the urging means Therefore, the urging force applied to the upper unit can be reduced. As a result, when the upper unit is opened, even if the center of gravity of the upper unit is displaced in the above direction, the urging force in the opening direction applied to the upper unit is reduced, so that the upper unit is vigorously rearward of the first shaft. Can be prevented from falling down. Further, when the upper unit is closed, the urging force applied to the upper unit in the opening direction is small, so that a large force is required to close the upper cover even if the center of gravity of the upper unit is displaced in the above direction. Can be suppressed. Therefore, even if the slide part of the upper unit slides and the center of gravity of the upper unit is displaced, an appropriate cushioning performance can be obtained.

  As described above, according to the present invention, there is an excellent effect that the opening / closing operation of the upper unit having the slide mechanism that can be rotated with respect to the apparatus main body can be favorably performed.

Embodiments of the present invention will be described below in detail with reference to the drawings.
FIG. 2 illustrates an image forming apparatus including a scanner according to the present embodiment, that is, a digital multifunction peripheral (hereinafter simply referred to as a multifunction peripheral). The multifunction machine includes an image forming unit 1000, a scanner unit 2000, and an automatic document feeder (hereinafter referred to as ADF) 3000. FIG. 3 is a schematic sectional view showing the copying machine. In FIG. 3, a copying machine includes a photosensitive drum 1 as an image carrier, a charging device 2, a developing device 3 as a developing means, a cleaning device 4 for cleaning the photosensitive drum 1, and an electrostatic latent image on the photosensitive drum 1. The image forming unit 1000 includes an optical writing unit 6 that is an LSU (exposure optical system) for writing an image.

  As the optical writing unit 6, for example, an optical signal corresponding to image information read by a scanner or the like is emitted from a semiconductor laser, and laser light is scanned by a polygon mirror that is rotationally driven. Use the one that writes the optical signal 6a corresponding to the color-separated image information on the photosensitive drum 1 through the lens for converging and the surface tilt correction of the polygon mirror and the mirror for deflecting the laser beam. Can do.

  A paper feed unit 200 is provided below the image forming unit 1000. The paper feed unit 200 includes a paper feed cassette 7 and a paper feed roller 9. The paper feed cassette 7 stores therein transfer paper 8 as a transfer material. The paper feed roller 9 is for separating and feeding the transfer paper 8 in the paper feed cassette 7 one by one. The transfer paper 8 fed by the paper feed roller 9 is temporarily kept in front of the photosensitive drum 1, and the leading edge of the image formed on the photosensitive drum 1 and the leading edge of the transfer paper 8 are the photosensitive member. The sheet is fed in synchronism with the rotation of the photosensitive drum 1 at a timing when the nip portion between the drum 1 and the transfer roller 10 reaches almost the same time. Further, a registration roller pair 11 is provided as a transfer material conveying means for refeeding the transfer paper 8.

  Further, above the image forming unit 1000, as a fixing unit having a fixing roller 14 and a press roller 15 including a heater rotatably disposed so as to be pressed against each other across the conveyance path of the transfer paper 8. A fixing device 16 is provided. On the downstream side of the fixing device 16 in the transfer paper conveyance direction, the transfer paper 8 that has passed through the fixing nip between the fixing roller 14 and the press roller 15 is used as a paper discharge tray formed on the upper cover 1200 of the copying machine. A paper discharge roller 18 for discharging the paper to the paper discharge surface 1210 is provided.

  Further, a scanner unit 2000 as a reading unit is provided further above the image forming unit 1000. The scanner unit 2000 is provided with a document illumination light source and a reading traveling body composed of a mirror in order to perform scanning scanning of a document placed on the contact glass. The reading traveling body moves in a direction (sub-scanning direction) orthogonal to the paper discharge direction, and reads an image of the document placed on the contact glass. The image information scanned by the reading traveling body is read as an image signal into a CCD installed behind the lens, and the read image signal is digitized and subjected to image processing. An electrostatic latent image is formed on the surface of the photoreceptor 1 by light emission of a laser diode (not shown) of the optical writing unit 6 based on the image-processed signal. The optical signal from the laser diode reaches the photosensitive drum 1 through a known polygon mirror or lens.

  The document placed on the scanner unit 2000 can be output to the image forming unit 1000 by an instruction from the operation unit 1100. The ADF 3000 is an automatic document feeder, and even when there are a plurality of documents to be copied, a plurality of documents are set on the tray 3100 provided in the ADF 3000, and a copy instruction is given once from the operation unit 1100, whereby It is possible to output a copy of a plurality of documents to the forming unit 1000 with one touch.

  In the copying machine having such a configuration, first, the photosensitive drum 1 is uniformly charged by the charging device 2 during rotation. Next, the optical writing unit 6 is driven based on the image information read from the outside, whereby an electrostatic latent image is formed in the charging area (image forming area) of the photosensitive drum 1. The electrostatic latent image is developed by a developer (toner) supplied from the developing roller 3a of the developing unit 3 to become a visible toner image.

  On the other hand, while the toner image is being formed on the photosensitive drum 1, the transfer paper 8 is pulled out from the paper feed cassette 7 by the paper feed roller 9, and the leading end thereof is brought into contact with the nip portion of the registration roller 11. Wait in contact. The transfer paper 8 is sent out to a transfer nip T1 formed by the photosensitive drum 1 and the transfer roller 10 when the registration roller 11 starts rotating at the timing when the toner image is superimposed on the photosensitive drum 1. It is. Then, after the toner image on the photosensitive drum 1 is transferred at the transfer nip T1, it is discharged by contact with a discharging brush (not shown). The discharged transfer paper 8 is mechanically separated from the photosensitive drum 1 and then sent to the fixing device 16.

  The fixing device 16 sandwiches the transfer paper 8 between the fixing roller 14 and the press roller 15, thereby heating and pressurizing the transfer paper 8 to fix the toner image on the transfer paper 8. The transfer paper 8 on which the toner image is fixed in this manner is discharged onto the paper discharge surface 1210 by the paper discharge roller 18.

  Residual toner remaining on the surface of the photosensitive drum 1 after passing through the transfer nip T1 is removed from the photosensitive drum 1 by the cleaning blade of the cleaning device 4 and collected.

  In this copying machine, the transfer paper transport path passing through the nip formed by the registration roller pair 11, the transfer nip T1, and the fixing nip T2 is transported in a substantially vertical direction from the bottom to the top. In this way, the transfer paper 8 can be vertically conveyed to achieve downsizing and shortening of the first print time.

  In the copying machine of this embodiment, the photosensitive drum 1, the charging device 2, the developing device 3, and the cleaning device 4 are integrally formed as a process cartridge 110, and are detachable from the printer body. In the process cartridge 110, a photosensitive drum 1, a charging device 2, a developing device 3, and a cleaning device 4 are provided in a single housing in a layout as shown in the figure. As described above, since a plurality of members including the charging device 2 and the photosensitive drum 1 are integrally configured as the process cartridge 110, replacement of these members can be easily performed.

[Reference configuration example]
FIG. 4 shows a printer 1000a which is an image forming apparatus having only a printer function. FIG. 5 is a diagram in which the printer 1000a shown in FIG. 4 is opened.
The upper cover 1200a is fastened to an upper frame 1300a and an upper frame (not shown) provided on the opposite side of the upper cover in the left-right direction with respect to the upper frame 1300a. One upper unit 1500a is provided. Further, an LSU (exposure optical system) is held between the upper frames. The upper unit 1500a includes a lock claw and a lock release lever that are locked when the upper unit 1500a is closed, and the upper frame 1300a includes a torsion spring 1530a at the shaft portion. The urging force of the torsion spring 1530a has a torque for releasing the upper unit 1500a at an appropriate speed. When the lock is released, the upper unit 1500a is slowly jumped to the maximum opening angle by the urging force of the spring. The shaft portion of the upper frame (not shown) is provided with a torsion spring similar to the torsion spring 1530a, and functions in the same manner as the torsion spring 1530a.

FIG. 6 is a diagram in which the multifunction machine shown in FIG. 2 is opened. FIG. 7 is a perspective view showing a state where the upper cover 1200 of the copying machine shown in FIG. 2 is opened.
The upper cover 1200 is fastened to an upper frame 1300 and an upper frame 1301 that are pivotally supported by a shaft 1310 that penetrates the rear side of the main body from side to side, and forms an upper unit 1500. The upper frames 1300 and 1301 hold an LSU (exposure optical system) therebetween. The upper unit 1500 has a lock claw and a lock release lever (not shown) that are locked when the upper unit 1500 is closed, and the upper frame 1300 is provided with a torsion spring 1530 at its shaft portion. Note that a torsion spring (not shown) similar to the torsion spring 1530 is also provided on the shaft portion of the upper frame 1301. As shown in FIG. 2, the upper cover 1200 is provided with pedestal portions 1250 and 1251 protruding upward so as to straddle the paper discharge surface 1210, and the scanner unit 2000 is located above the paper discharge surface 1210 of the image forming unit 1000. A space for stacking the sheets is provided to be attached to the pedestals 1250 and 1251 of the upper cover 1200.

  When the upper cover 1200 of the copying machine is opened as shown in FIG. 7, the scanner unit 2000 and the ADF 3000 attached to the scanner are also opened together with the upper cover 1200. Here, the opening / closing operation force of the upper unit 1500, which is a rotating animal due to the weight of the scanner unit 2000, the ADF 3000, etc., does not become too large, and when the hand is released, the user is accelerated to cause a danger, or In order to prevent damage due to a large impact, a buffer mechanism is required.

  The upper unit 1500 side buffer mechanism engaging portion is the upper cover 1200, so that when the printer type as shown in FIG. 4 and the multifunction peripheral as shown in FIG. It is only necessary to newly design the upper cover 1200 and the buffer mechanism for increasing the weight of the scanner unit 2000 and the ADF 3000 provided on the upper cover 1200 without changing the image forming unit 1000). It is possible to reduce the number of parts and to make the housing assembly common.

  FIG. 8 shows an example of parts constituting a buffer mechanism provided in the copying machine shown in FIG. FIG. 8 shows an example of components constituting the buffer mechanism provided on the left side of the copying machine shown in FIG. 2, but the buffer mechanism provided on the opposite side is similar to the buffer mechanism except for the left and right differences. Therefore, the description thereof is omitted. Since the configuration is substantially the same except for the difference between the left and right of the apparatus main body, the configuration on the left side of the drawing will be described unless otherwise specified.

  The shock absorbing mechanism is provided on the arm 1520 that is pivotally supported by the upper cover 1200 and rotates, the torsion spring 1540 provided on the rotating shaft of the arm 1520, the main body frame, and the arm 1520 on the side where the rotating shaft is not provided. The slide rail 1510 in which the end portion 1520c slides and the elastic member 1560 provided in the end portion 1510a of the slide rail 1510 to be engaged with the tips 1520a and 1520b of the arm 1520 are configured. One arm of the torsion spring 1540 is engaged to urge the arm 1520 in the rotational direction, and the other arm is engaged to the upper cover 1200.

  The slide surface side of the arm 1520 that slides with respect to the slide rail 1510 has a key shape in which a protrusion is provided from the arm portion to the abutting side of the main body, and the tip ends 1520a and 1520b of the key shape have a shape in which a cylinder protrudes left and right. It has become. The columnar shape slides in the slide rail 1510. Since the slide rail 1510 has a roof-shaped roof 1510b that holds both sides of the column (tips 1520a and 1520b), the arm 1520 may come off the slide rail 1510. Absent. In addition, when moving to the end 1510a of the slide rail 1510, the key shape of the arm 1520 engages with the slide rail 1510 to regulate the maximum opening angle and when an overload is applied after the maximum opening. Also, force is not applied to the roof 1510b of the slide rail 1510.

  In the vicinity of the upper cover closed state by the torsion spring 1540, the arm end portion 1520c presses the main body downward, so that the upper unit 1500 obtains an upward torque. It plays a role as an impact buffering mechanism. At this time, the torsion spring 1540 depends on the ratio of the distance in the slide surface parallel direction between the rotation shaft of the arm 1520 and the rotation shaft of the upper unit 1500 and the slide surface parallel distance between the rotation shaft of the arm 1520 and the arm slide surface contact point. Therefore, a larger buffering effect can be obtained than when the torsion spring 1540 is incorporated in the shaft portion of the upper unit 1500. This represents that it can be achieved cheaper by obtaining the same force. Further, since the relative angle between the upper cover 1200 and the arm 1520 changes with the rotation of the upper cover 1200, the flip-up force can be changed at any time as the center of gravity of the upper unit 1500 moves. Since the slide side end 1520c of the arm 1520 moves in the slide rail 1510, a force can be obtained only in the direction perpendicular to the slide surface if there is little friction, and the opening / closing force can be regulated without impairing the operational feeling. Alternatively, the buffering action may be enhanced by applying friction on the sliding surface in the slide rail 1510.

  When the upper unit 1500 is further opened, the center of gravity reaches a position above the rotation axis in the vertical direction at a certain angle. That is, after the said angle, the force which rotates back by the weight of the upper unit 1500 generate | occur | produces. As a result, as in the case of closing the upper cover, the heavy object rotates vigorously backward, causing damage to people and objects behind the machine, or damage to the equipment. Here, since the arm end portion 1520c in the slide rail 1510 loosens the acceleration by the elastic member 1560 and abuts against the end portion 1510a of the slide rail 1510 to restrict the maximum opening angle, the above-described danger can be avoided. The elastic member 1560 may be a compression spring, a urethane elastomer, a foam member, rubber, an oil damper, or the like, but the compression spring is inexpensive and easy to earn a stroke. Here, since the compression spring in the slide rail 1510 has an outer diameter larger than the gap of the roof 1510b of the slide rail 1510, the spring does not jump out of the slide rail 1510 and is safe. Further, the natural angle of the torsion spring 1540 is set near the opening / closing angle at which the center of gravity is above the opening axis in the vertical direction. Thus, after the angle, the torsion spring 1540 generates a force in the direction in which the tips 1520a and 1520b of the arm 1520 press the roof 1510b of the slide rail 1510, so that the upper unit 1500 can rotate backward. A rotational biasing force is applied in the direction of prevention.

  According to this mechanism, there is no need for a mechanism for taking a width on the main body frame side, a smart configuration can be achieved, and an opening / closing force buffering mechanism can be incorporated without affecting the appearance and machine size.

  Further, by incorporating the rotation shaft of the arm 1520 and the torsion spring 1540 in the pedestal part 1250 on which the scanner unit 2000 is installed in the upper cover 1200 which is a non-common part, there is less space restriction and a relatively large torsion spring. 1540 can also be incorporated. Further, the torsion spring 1540 is less visible to the user, and as a result, the risk that the torsion spring 1540 becomes tangled with hair is reduced.

  The upper unit 1500 rotated by the buffer mechanism as described above includes an upper cover 1200 having a paper discharge surface 1210, a scanner unit 2000 fixed to the upper cover 1200 via pedestals 1250 and 1251, and the scanner unit 2000. Here, including the ADF 3000 that is movably installed, the internal unit of the image forming unit 1000 can be replaced with one action for opening and closing the upper unit 1500, so that the replacement becomes easy.

  Further, when a lineup of ADF-free multifunction peripherals is provided, it is possible to prevent an increase in dedicated parts and reduce manufacturing costs by removing a part of the buffer mechanism so as to have a balanced configuration. For example, the torsion spring provided on the rotation shaft of the arm installed on both sides is only one rotation shaft, the common spring with the printer installed on the main body is changed, the setting of the spring is changed, and the like. The spring left at this time is closer to the position of the center of gravity of the upper unit 1500, so that the balance of spring-up is improved.

  Although the torsion spring is loaded on the shaft part of the arm, it can be opened and closed without increasing the space by installing a damper mechanism such as a torque limiter that uses friction force or an oil damper on the shaft part of the arm. It is also possible to improve the opening / closing stability and safety of objects.

[Configuration example 1]
Next, consider a case where the upper unit 1500 has a slide portion 1800 as shown in FIG. In the present embodiment, the slide unit 1800 is provided with a scanner.
When the slide unit 1800 provided with a heavy object such as a scanner slides on the upper unit 1500, the angular distribution of the rotational moment necessary for the opening / closing operation of the upper unit 1500 changes. Therefore, it is difficult to achieve sufficient buffer performance with the configuration of the buffer mechanism optimized before the slide. Therefore, in order to solve this problem, it is possible to cope with a configuration that suppresses the acceleration of the upper unit 1500 as a whole by making the movement generally sluggish, that is, by always applying a large torque load. According to the method, there is a drawback that the operation force becomes large. Therefore, in the present embodiment, the following configuration is provided so that appropriate buffer performance can be obtained even when the slide portion 1800 is slid.

  As shown in FIG. 9, the torque generating mechanism provided in the shaft portion 1620d of the arm 1620 includes a gear 1700a that is supported by the arm 1620 at one end and coaxial with the arm 1620 at the other end so as to be rotatable. A torsion spring 1640 supported by the support member 1700 is used. Further, the arm 1620 having the slide surface that slides with respect to the slide rail 1610 of the arm 1620, the slide rail 1610, a member (not shown), and the like are configured as the arm 1520 and the slide rail 1510 in the multifunction machine shown in FIG. Based on the same principle as the buffer mechanism, the upper unit 1500 having the slide 1800 is configured to be able to buffer an impact during the opening / closing operation.

  When the slide unit 1800 provided with a heavy load scanner slides backward (in the direction of arrow A in FIG. 1), the locus of center of gravity at the time of opening changes, and the upper unit 1500 moves forward (to the right in the drawing in FIG. 1). It is difficult to fall, and it is easy to fall backward (to the left in FIG. 1). In order to correct this tendency, when the slide portion 1800 on the upper unit 1500 slides backward, the gear portion 1800a, which is a rack provided in the slide direction on the bottom surface of the slide portion 1800, The gear portion 1700a provided in the circumferential direction of the support member 1700 that fixes the angle of the torsion spring 1640 provided in the shaft portion 1620d to the upper unit 1500 is rotated. Thus, the torsional state of the torsion spring 1640 in the closed state changes in the loosening direction, so that the torque applied to the arm 1620 in the closed state decreases, and the torque angle characteristic of the torsion spring 1640 during the opening / closing operation decreases in the closing direction. The switching angle becomes smaller. As a result, even after the slide, it is possible to produce an optimized buffer performance equivalent to that before the slide, and the operation force does not become too high.

  At this time, when it is desired to adjust the angle variation of the torsion spring 1640 with respect to the slide amount, it is possible to adjust the diameter of the gear 1700a provided on the support member 1700 of the torsion spring 1640, but there is a space limitation. In some cases, an idler gear may be used. At this time, the rotation direction changes depending on the number of gears, so care must be taken.

  Further, in this method, since the torque generated by the torsion spring 1640 in the closed state is applied in the direction in which the slide portion 1800 is slid backward, the slide provided in the upper unit 1800 as shown in FIG. When the slide lock composed of the lock engagement portion 1800b and the slide lock switch 1400 engaged with the slide lock engagement portion 1800b is released, the mechanism can be configured to automatically slide backward. In this case, if the operation force for operating the slide part 1800 to the front becomes large, a counter load caused by an elastic member 1810 such as a compression spring, a tension spring, or a torsion spring is applied to the slide part 1800 as shown in FIG. By adding, the presence / absence of an automatic slide at the time of unlocking, the operation force, etc. can be freely set. In the present embodiment, a tension spring is used as the elastic member 1810.

  Further, the support member 1700 of the torsion spring 1640 is configured to move in the thrust direction as shown in FIGS. 11 and 12 and is pressed outward by the thrust direction elastic force of the torsion spring 1640. A load receiving portion 1700b that engages with the upper unit 1500 at each slide position and a corresponding load receiving engagement portion 1900 on the upper unit 1500 side are provided on the outside of the support member 1700. Make sure they are engaged as shown. Further, the load receiving portion 1700b and the load receiving engagement portion 1900 engage with each other to form a rotation stop portion of the support member 1700, which is provided in the load receiving engagement portion 1900 shown in FIG. 13A in a normal state. The support member 1700 is prevented from rotating by engaging the groove 1900a and the load receiving portion 1700b. At this time, the gear portion 1700a of the support member 1700 is not engaged with the gear portion 1800a of the slide portion 1800. Then, as shown in FIG. 14, a part of the slide lock switch 1400 has a role of a clutch that moves the support member 1700 of the torsion spring 1640 in the thrust direction so that the gear portion 1700a and the gear portion 1800a are engaged with each other. When sliding, the gear portion 1700a and the gear portion 1800a mesh with each other, and the support member 1700 rotates in the direction of the arrow shown in FIG. When the slide lock switch 1400 is released, the engagement between the gear portion 1700a and the gear portion 1800a is released, and the load receiving portion 1700b of the support member 1700 and the load receiving engagement portion 1900 of the upper unit 1500 shown in FIG. And the groove 1900b engage with each other to suppress the rotation of the support member 1700. According to this configuration, since the load is not applied to the gear portion 1700a but is applied to the load receiving portion 1700b when the open / close is used, the load is received by the load receiving portion 1700b. Can be prevented.

  In the above configuration, the movement amount is adjusted by the gear so that the slide amount and the angle fluctuation of the torsion spring 1640 can be easily controlled. However, the support member 1700 is not provided, and the slide portion 1800 is configured as shown in FIG. The arm of the torsion spring 1640 may be directly supported. According to this structure, addition of a member can be suppressed and it can be set as a simpler structure.

[Configuration example 2]
Next, FIG. 16 shows a torque generation mechanism provided on the shaft portion 1620d of the arm 1620 using a cam mechanism.
As shown in FIG. 16A, a cam portion 1630 a is provided in the thrust direction of the arm 1630, and a cam portion 1650 a is provided on the opposing cam member 1650. The opposing cam member 1650 is pressed against the arm 1630 by the elastic member 1660 as shown in FIG. 16B, and the cam portion 1630a and the cam portion 1650a are pressed against each other. Rotation biasing force works. According to this configuration, the direction and distribution of torque generation can be designed freely. For example, as shown in FIG. 17, when the opening / closing angle is 40 ° and the center of gravity of the upper unit 1500 is directly above the shaft 1310 that is the rotation axis, the cams rotate at an opening / closing angle of 40 ° as shown in FIG. Engage in ways that do not produce power. Therefore, for example, as shown in FIG. 16B (open / close), a rotational biasing force is applied in a direction in which the upper unit 1500 is opened when the open / close angle is 0 ° to 40 °, and in a direction in which the upper unit 1500 is closed when the open / close angle is larger than 40 °. The cam portion 1630a and the cam portion 1650a are engaged with each other as shown in FIG. 16C (opening angle is 80 °). Thereby, the buffering force corresponding to the rotation locus of the center of gravity can be generated.

  When the slide unit 1800 provided with a heavy object such as a scanner slides backward, the locus of center of gravity of the upper unit 1500 at the time of opening changes, and the upper unit 1500 is difficult to fall forward, and It becomes easy to fall. In order to correct this tendency, when the slide portion 1800 on the upper unit 1500 slides to the rear side of the device, the gear portion 1800a provided on the bottom surface of the slide portion 1800 is connected to the shaft portion 1620d of the arm 1620. The gear portion 1650b provided in the circumferential direction of the provided opposing cam member 1650 is rotated from the position before the slide shown in FIG. 16D to the position after the slide shown in FIG. As a result, as shown in FIG. 16, in the cam biasing force distribution, the force applied in the opening direction is reduced when the opening / closing angle is around 0 °, and the angle biased in the closing direction can be accelerated. That is, the angle at which the torque angle characteristic is switched in the closing direction becomes smaller. Thereby, even after the slide portion 1800 is slid, it is possible to produce an optimized buffer performance equivalent to that before the slide portion 1800 is slid, and the operation force is not excessively increased.

  In addition, here, the engaging portion of the arm side and the opposing member side is both cam-shaped, but the cam shape may be only one side, and in that case, the other side is always provided with a protrusion that abuts the cam portion. Equivalent effect can be obtained. Here, in order to transmit torque generated by the cam in the rotation direction without waste, it is desirable that the same cam shape is arranged in a cycle of 180 °, and two protrusions are provided on the center axis on the object.

As described above, according to the present embodiment, the image forming unit 1000 that is an image forming unit that forms an image, and the upper unit 1500 that is rotatable with respect to the image forming unit 1000 about the shaft 1300 that is the first shaft. The upper unit 1500 is provided with a slide unit 1800 that is slidable in a direction perpendicular to the axial direction of the shaft 1300 and an urging force in the direction in which the upper unit 1500 opens with respect to the image forming unit 1000. In a copying machine, which is an image forming apparatus provided with an urging means for applying, the slide unit 1800 is moved upward in a direction from the opposite side of the upper unit 1500 to the side to which the shaft 1300 is attached. The urging force applied to the upper unit 1500 from the urging means as the unit 1500 slides. And a biasing force changing means for changing to be small. Thus, when opening the upper unit 1500, even if the center of gravity of the upper unit 1500 is displaced in the above direction, the urging force in the opening direction applied to the upper unit 1500 is reduced, so that the upper unit 1500 is more powerful than the shaft 1300. Can also be prevented from falling backwards. Further, when the upper unit 1500 is closed, since the urging force applied to the upper unit 1500 in the opening direction is small, a large force is required to close the upper unit 1500 even if the center of gravity of the upper unit 1500 is displaced in the above direction. Can be suppressed. Therefore, even if the slide portion 1800 of the upper unit 1500 slides and the center of gravity of the upper unit 1500 is displaced, an appropriate cushioning performance can be obtained. Therefore, the upper unit 1500 having the slide portion 1800 that can be rotated with respect to the image forming portion 1000 can be opened and closed safely by an inexpensive buffer mechanism.
Further, according to the present embodiment, the urging means includes the arm 1620 that can rotate with respect to the upper unit 1500 around the shaft portion 1620d that is the second shaft provided in the upper unit 1500, and the arm 1620. Generation of torque such as a slide rail 1610 which is a guide provided in the image forming unit 1000 and a torsion spring 1640 which applies a rotational urging force to the arm 1620 for guiding an end of the shaft not supported by the shaft along the guide surface. The biasing means is configured to apply a biasing force in the opening direction to the upper unit 1500 when the arm 1620 presses the guide surface by a rotational biasing force from the torque generating member. , In a direction from the opposite side of the upper unit 1500 to the side where the shaft 1300 is attached toward the side where the shaft 1300 is attached. According Id unit 1800 slides relative to the upper unit 1500 constitute the biasing force changing means so that the rotational biasing force is reduced.
Thereby, since the pressing force with which the arm 1620 presses the guide surface changes according to the slide position of the slide portion 1800, the urging force in the opening direction applied to the upper unit 1500 also changes. Therefore, by setting the rotational biasing force to a predetermined magnitude according to the slide position of the slide portion 1800, the biasing force in the opening direction applied to the upper unit 1500 is set to an appropriate magnitude according to the slide of the slide portion 1800. It becomes possible to do. That is, as the slide portion 1800 slides toward the shaft 1300 with respect to the upper unit 1500, the rotational biasing force applied to the arm 1620 from the torque generating means is reduced. By doing so, since the pressing force with which the arm 1620 presses the guide surface is reduced, the urging force in the opening direction applied to the upper unit 1500 is also reduced. Therefore, when opening the upper unit 1500, even if the center of gravity of the upper unit 1500 is displaced rearward, the urging force in the opening direction applied to the upper unit 1500 is reduced, so that the upper unit 1500 is more powerfully rearward than the shaft 1300. Can be prevented from falling down. Further, when the upper unit 1500 is closed, since the urging force applied to the upper unit 1500 in the opening direction is small, even if the center of gravity of the upper unit 1500 is displaced rearward, a large force is required to close the upper unit 1500. It is possible to suppress the necessity. Thus, even if the slide portion 1800 of the upper unit 1500 slides and the center of gravity of the upper unit 1500 is displaced, an appropriate buffering performance can be obtained. Therefore, the upper unit 1500 having the slide portion 1800 that can be rotated with respect to the image forming portion 1000 can be opened and closed safely by an inexpensive buffer mechanism.
Further, according to the present embodiment, the torque generating member is a torsion spring 1640 having one end locked to the upper unit portion and the other end locked to the arm 1620, and the rack aligned in the sliding direction of the slide portion 1800. And a support member 1700 which is a rotating member having a gear portion 1700a meshing with the gear portion 1800a on the circumference, and the support member 1700 is used as the upper unit portion for locking the one end, and the direction toward the above. The urging force changing means is configured by arranging the torsion spring 1640 in a winding direction such that the rotational urging force decreases as the heel slide portion 1800 slides relative to the upper unit 1500. Thereby, the buffer mechanism in the opening / closing operation of the upper unit 1500 can be configured at low cost.
Further, according to the present embodiment, the torque generating means including the urging means and the rotation urging force changing means includes the cam portion 1630a provided in the thrust direction of the arm 1630 and the rotation shaft of the arm 1630. It consists of a facing member 1650 having a cam portion 1650a facing the cam portion 1630a of the arm 1630 from the thrust direction, and an elastic member 1660 that presses the facing member 1650 in the arm 1630 direction. The cam portion 1600a and the cam portion 1630a are provided on the arm 1630 and the opposing member 1650, and are pressed against each other, thereby exhibiting torque angle characteristics according to the cam shape of the cam portion during rotation, and moving the center of gravity of the slide portion 1800. It is possible to produce an optimal distribution of torque generation.
Further, according to the present embodiment, the torque generating means comprising the urging means and the rotational urging force changing means is provided from the thrust direction of the arm rotation shaft and the protrusion provided in the thrust direction of the arm. Composed of an opposing member having a cam portion facing the projection of the arm and an elastic member that presses the opposing member in the arm direction, it exhibits torque angle characteristics according to the cam shape of the cam portion during rotation, An optimal torque generation distribution corresponding to the center of gravity movement of the slide portion 1800 can be generated.
Further, according to the present embodiment, the torque generating means composed of the urging means and the rotational urging force changing means includes the cam portion provided in the thrust direction of the arm and the thrust direction of the rotation shaft of the arm. Composed of an opposing member having a protruding part facing the cam part of the arm and an elastic member that presses the opposing member in the arm direction, it exhibits torque angle characteristics according to the cam shape of the cam part during rotation, An optimal torque generation distribution corresponding to the center of gravity movement of the slide portion 1800 can be generated.
Further, according to the present embodiment, by providing the image forming unit for forming an image in the image forming unit 1000, it is not desirable to shock the apparatus main body, and the image forming unit provided inside the image forming unit 1000 is replaced. Therefore, the opening / closing mechanism of the image forming apparatus that needs to open / close the upper unit 1500 many times can be made safe and reliable.
In addition, according to the present embodiment, the upper unit 1500 is provided with a scanner which is an image reading unit that reads image information of a document. Since it is often disposed above the unit, opening and closing at the same time as the upper unit 1500 can prevent the inside of the apparatus main body from being hindered in opening and closing operations for exposure.
Further, according to the present embodiment, since the scanner is provided on the slide unit 1800, the scanner is independent from the image forming unit 1000, so that there is no problem in use even when the position is changed with respect to the main body. . Therefore, the visibility and workability of the image forming unit can be improved by moving the scanner disposed above the copying machine.
Further, according to the present embodiment, the upper unit 1500 is provided with the sheet discharge surface 1210 which is a sheet placement portion for placing the sheet member after image formation in a gap provided below the slide portion 1800. Installation space can be reduced. Further, by sliding the slide portion 1800 provided above the paper discharge surface 1210, it is possible to improve the paper discharge visibility and the ease of taking out the paper discharge.
According to this embodiment, at least two or more selected from the photosensitive drum 1 as an image carrier, the developing device 3 as a developing unit, the charging device 2 as a charging unit, and the cleaning device 4 as a cleaning unit are provided. The process cartridge 110 is integrally formed and is detachable from the apparatus main body. The process cartridge 110 is provided in the image forming unit 1000, and the process cartridge 110 is exposed by the opening operation of the upper unit 1500. . As a result, the process cartridge 110 can be replaced by opening the upper unit 1500, so that the process cartridge 110 is indispensable to the user in the running with the minimum number of steps, that is, taking out the process cartridge 110 by opening one portion of the apparatus main body. The replacement work 110 can be an easy work.
In addition, according to the present embodiment, an oil damper is provided in the shaft portion 1620d in addition to the torque generating means, so that a torque corresponding to the opening / closing speed of the upper unit 1500 can be generated even when the user performs a rough operation. Thus, the parts can be prevented from being damaged.
In addition, according to the present embodiment, the upper unit 1500 is provided with the elastic member 1810 that presses the slide portion 1800 toward the front side of the slide, so that when the slide portion 1800 is slid, the torque generating member is connected to the slide mechanism via the gear. It is possible to cancel the force that pushes the rear side and slide the slide portion 1800 with a small operating force.
Further, according to the present embodiment, the slide lock switch 1400 that fixes the slide portion 1800 to the upper unit 1500 so as not to move is provided. The slide lock switch 1400 causes the slide portion 1800 to move relative to the upper unit 1500. When fixed, the gear portion 1800a and the gear portion 1700a do not engage with each other, and when the slide portion 1800 is released from being fixed, the gear portion 1800a and the gear portion 1700a engage with each other. . As a result, the rotational biasing force generated between the torque generating means and the arm 1620 is received by a portion other than the gear, so that the dynamic load when the upper unit 1500 is opened and closed is not applied to the gear portion 1700a and the gear portion 1800a. Therefore, it is possible to prevent the power from being transmitted to the slide portion 1800 when the gear is broken or the upper unit 1500 is opened.
Further, according to the present embodiment, the image forming unit 1000 that is the lower unit and the shaft 1310 that is the first shaft provided in the image forming unit 1000 with respect to the image forming unit 1000 can be rotated. In a buffer mechanism provided between the upper unit 1500 provided with a slide part 1800 that slides in a direction perpendicular to the axial direction of the shaft 1310 provided at the upper part, the upper unit 1500 opens in the direction in which the image forming part 1000 opens. The slidable portion 1800 is provided in a direction from the opposite side of the upper unit 1500 to the side to which the shaft 1300 is attached toward the side to which the shaft 1300 is attached. The urging force applied to the upper unit 1500 from the urging means as the upper unit 1500 slides. And a biasing force changing means for changing to decrease. Thus, when opening the upper unit 1500, even if the center of gravity of the upper unit 1500 is displaced in the above direction, the urging force in the opening direction applied to the upper unit 1500 is reduced, so that the upper unit 1500 is more powerful than the shaft 1300. Can also be prevented from falling backwards. Further, when the upper unit 1500 is closed, since the urging force applied to the upper unit 1500 in the opening direction is small, a large force is required to close the upper unit 1500 even if the center of gravity of the upper unit 1500 is displaced in the above direction. Can be suppressed. Therefore, even if the slide portion 1800 of the upper unit 1500 slides and the center of gravity of the upper unit 1500 is displaced, an appropriate cushioning performance can be obtained. Therefore, the upper unit 1500 having the slide portion 1800 that can be rotated with respect to the image forming portion 1000 can be opened and closed safely by an inexpensive buffer mechanism.

1 is a schematic configuration diagram of a copier in which an upper unit according to the present embodiment has a slide portion. 1 is a schematic configuration diagram of a copying machine including a scanner according to an embodiment. FIG. 3 is a schematic cross-sectional configuration diagram of a copying machine including a scanner. 1 is a schematic configuration diagram of a printer that is an image forming apparatus having only a printer function. The perspective view of the state which open | released the printer. The perspective view of the state which open | released the multifunctional device. FIG. 3 is a perspective view of a state where an upper cover of the copying machine is opened. FIG. 2 is a schematic configuration diagram of a buffer mechanism provided in a copying machine. 2 is a schematic configuration diagram of a buffer mechanism in Configuration Example 1. FIG. The schematic block diagram in the case of having a slide lock switch. The figure which showed the state which a load receiving engagement part and a load receiving part do not engage in a normal state. The figure which showed the state which the load receiving engaging part and the load receiving part engaged when sliding. (A) The figure which showed the groove | channel provided in the load receiving engagement part. (B) The perspective view which looked at the supporting member from the load receiving part side. The schematic block diagram at the time of using a slide lock switch as a clutch. The schematic block diagram at the time of supporting the arm of a torsion spring directly with a slide part. (A) The schematic block diagram at the time of using a cam mechanism for a torque generation mechanism. (B) The figure which showed the engagement state of the cam part in case an opening-and-closing angle is 40 degrees. (C) The figure which showed the engagement state of the cam part in case an opening-and-closing angle is 80 degrees. (D) The figure which showed the cam mechanism before the slide of a slide part. (E) The figure which showed the cam mechanism after the slide of a slide part. The schematic diagram which shows the state which the gravity center of the upper unit before and after the slide of the slide part opened / closed through the shaft. The graph which shows the relationship between a gravity center moment and the rotation moment of an upper unit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photosensitive drum 2 Charging apparatus 3 Developing apparatus 4 Cleaning apparatus 110 Process cartridge 1000 Image forming part 1200 Upper cover 1210 Paper discharge surface 1310 Shaft 1400 Slide lock switch 1500 Upper unit 1620 Arm 1620d Shaft part 1630 Arm 1630a Cam part 1640 Torsion spring 1650 Opposing Cam member 1650a Cam portion 1700 Support member 1700a Gear portion 1800 Slide portion 1800a Gear portion

Claims (11)

An image forming means for forming an image;
An upper unit rotatable about the first axis with respect to the image forming means;
A slide portion provided in the upper unit and slidable in a direction perpendicular to the axial direction of the first shaft;
An image forming apparatus comprising: an urging unit that applies an urging force to the upper unit with respect to the image forming unit;
As the slide portion slides relative to the upper unit in a direction from the side opposite to the side on which the first shaft is attached of the upper unit to the side on which the first shaft is attached, An image forming apparatus comprising biasing force changing means for changing the biasing force applied to the upper unit from the means. The image forming apparatus according to claim 1.
An arm member that is rotatable with respect to the upper unit about a second axis provided in the upper unit, and the image formation that guides an end portion of the arm member that is not pivotally supported along a guide surface. A guide portion provided in the means, and a torque generating member that applies a rotational biasing force to the arm member, and the arm member presses the guide surface by the rotational biasing force from the torque generating member, The biasing means is configured to apply a biasing force in the opening direction to the upper unit,
As the slide portion slides relative to the upper unit from the opposite side of the upper unit to the side on which the first shaft is attached, An image forming apparatus, wherein the urging force changing means is configured to reduce the urging force. The image forming apparatus according to claim 2.
The torque generating member is a torsion spring having one end locked to the upper unit portion and the other end locked to the arm member, and the rack meshed in the sliding direction of the slide portion and the gear meshing with the rack And the rotation member is used as the unit portion that locks the one end, and the rotation biasing force is reduced as the slide portion slides relative to the upper unit in the direction toward the end. An image forming apparatus characterized in that the urging force changing means is configured by arranging the torsion spring in a posture in a proper winding direction. The image forming apparatus according to claim 2.
The torque generating means comprising the torque generating member and the rotational biasing force changing means includes a cam portion provided in the thrust direction of the arm member, and a cam portion of the arm member from the thrust direction of the rotation shaft of the arm member. An image forming apparatus comprising: a facing member having a cam portion facing the head; and an elastic member that presses the facing member toward the arm member. The image forming apparatus according to claim 2.
The torque generating means comprising the urging means and the rotation urging force changing means includes: a protrusion provided in the thrust direction of the arm member; and a protrusion of the arm member from the thrust direction of the rotation shaft of the arm member. An image forming apparatus comprising: a facing member having a cam portion facing the head; and an elastic member that presses the facing member toward the arm member. The image forming apparatus according to claim 2.
The torque generating means comprising the urging means and the rotational urging force changing means includes a cam portion provided in the thrust direction of the arm member, and a cam portion of the arm member from the thrust direction of the rotation shaft of the arm member. An image forming apparatus comprising: a facing member having a projecting portion that faces the surface; and an elastic member that presses the facing member toward the arm member. The image forming apparatus according to claim 1, 2, 3, 4, 5 or 6.
An image forming apparatus comprising an image reading means for reading image information of a document in the upper unit. The image forming apparatus according to claim 1, 2, 3, 4, 5, 6 or 7.
An image forming apparatus, wherein the upper unit is provided with a sheet placing portion for placing a sheet member after image formation in a gap provided below the slide portion. The image forming apparatus according to claim 1, 2, 3, 4, 5, 6, 7 or 8.
An image forming apparatus, wherein the upper unit is provided with an elastic member that presses the slide portion toward the slide front side. The image forming apparatus according to claim 1, 2, 3, 4, 5, 6, 7, 8, or 9.
A slide lock switch is provided to fix the slide portion so as not to move with respect to the upper unit. When the slide portion is fixed to the upper unit by the slide lock switch, the slide lock switch is provided. When the rack arranged in the sliding direction of the slide portion provided in the portion and the gear provided in the rotational biasing force changing means do not engage and the slide portion is released from being fixed, the rack and the gear An image forming apparatus configured to engage with each other. The lower unit,
Between the lower unit and an upper unit provided with a slide portion that is rotatable about a first axis provided on the lower unit and that slides in a direction perpendicular to the first axial direction. In the buffer mechanism provided,
A biasing means for imparting a biasing force to the lower unit in the direction in which the upper unit opens, on the opposite side of the upper unit from the side on which the first shaft is mounted; The urging force applied from the urging means to the upper unit is changed as the slide portion slides relative to the upper unit in a direction from the urging direction toward the side to which the first shaft is attached. A shock absorbing mechanism comprising biasing force changing means.

Images