JPH04112259U - electrophotographic equipment - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention relates to a small electrophotographic device that can be used as a facsimile, printer, or copying machine, and in particular, to facilitate the removal of jams in recording materials onto which toner images are transferred. The purpose of the present invention is to provide a small-sized electrophotographic device. [Structure] The present invention is similar to the prior art in that at least a part of the recording material conveyance path from the recording material feeding end to the entrance end of the image fixing means is unitized, but the present invention is particularly unique. The unit body is constructed so that it can be pulled out in stages along a direction substantially perpendicular to the axis of the photosensitive drum, and the conveyance unit is moved to a predetermined stage while maintaining the energized state of at least the fixing roller left on the apparatus main body side. The reason is that it is configured so that it can be pulled out.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is a small electrophotographic device that can be used as a facsimile, printer, or copier. In particular, an electronic system designed to facilitate the removal of jams from recording materials onto which toner images are transferred. Concerning photographic equipment.

0002

[Conventional technology]

Conventionally, in smaller electrophotographic devices, recording It is common to configure the upper and lower bodies to be able to be separated and opened along the paper conveyance path. be. However, if the main body is split into an open type structure, each main body has a structure that can withstand the opening operation. In addition to requiring sufficient precision and rigidity to Pulling and the like are also required, which leads to a complicated device configuration and an increased weight burden.

0003 In addition, in the above-mentioned apparatus, the developing device is generally disposed on the upper main body side. With this configuration, the impact force applied when the upper body is opened causes damage to the inside of the developing device. The toner carried on the developing sleeve may fall off and cause contamination inside the machine and the recording paper transport path. Easy to do. In addition, in a device that uses a pair of heat rollers as a means of fixing an unfixed toner image, When the transport path is opened, the gap between the heat roller pair (hereinafter referred to as the heat fixing roller pair) is also exposed. This poses a safety problem. Therefore, in the above device, the power to the fixing roller can be cut off in conjunction with the main body division operation. However, even with such a configuration, the heat fixing roller is insufficient immediately after the power is turned off. It is heated, which not only poses a safety problem, but also prevents the jam from being disposed of once the power is turned off. Even after turning the power on again, it takes a long time to recover to the fixing temperature that allows printing. Put it away.

0004 In order to eliminate this drawback, paper feed rollers and resistors installed on the conveyance path A transport unit that integrates rollers, transfer rollers, transport guides, and a pair of fixing rollers. There is a device in which the transport unit can be taken out along the drum axis direction. Proposed. (Unexamined Japanese Patent Publication No. 64-20564)

[0005] However, as mentioned above, the unit is moved along the direction perpendicular to the recording paper conveyance direction. A structure that can be pulled out prevents jammed paper from getting caught on the photoreceptor drum, etc. There is a risk of damaging the system. For this reason, as shown in Japanese Patent Publication No. 2-35314, the unit is replaced with a unit including a fixing roller. Divide into the knit and its upstream unit, and move each unit away from each other. , a technology is disclosed in which the recording material is attached so that it can be pulled out parallel to the recording material conveyance path. It is.

[0006]

[Problem that the idea aims to solve]

However, in the above device, depending on the jam position, the side walls of the device body (or The jam handling operation can be configured to pull out the unit on each side of the front or rear walls). The work space becomes unnecessarily large and the processing operations become complicated. In addition, as mentioned above, the unit body including the fixing roller can be drawn out from the main body of the apparatus. In order to ensure safety, it is necessary to turn off the power to the pair of fixing rollers when pulling out the Not only is there a problem with this, but also the fusing temperature rises when the power is turned on again after clearing the jam. You have to wait until the time comes.

[0007] Also, the fixing roller pair is not made into a unit, but is fixed to the main body of the device, and located upstream of it. There is also a device that is configured so that only the transport unit that is used can be pulled out toward the paper feed side along the transport direction. It has been proposed (Japanese Unexamined Patent Publication No. 60-63563), but it is necessary to install a transport unit for each jam treatment. Taking it out of the device not only increases the weight burden on the operator, but also damages the transport unit. In order to adopt a structure in which the drum extends long in the tangential direction of the photoreceptor drum, the amount of pullout is increased. This also increases the actual work load.

[0008] In addition, the conveyance path is not formed on a substantially straight line in the tangential direction of the drum, but at the transfer position. All conveyance processes arranged on the conveyance path while forming a reversible conveyance path in a U-shape. The means are integrated into a unit, and the unit body can be taken out in parallel to the conveyance direction. However, forming the conveyance path in a U-shape requires that the entire device be thick. It becomes fleshy and undesirable.

[0009] In view of these drawbacks of the conventional technology, it is possible to This allows you to safely and easily remove jams without causing the recording material to tear. The purpose of the present invention is to provide an electrophotographic device that can perform the following functions. Furthermore, this invention makes it possible to easily clear jams without increasing the burden on the operator. The purpose of the present invention is to provide an electrophotographic device with improved performance.

0010

[Means to solve the problem]

The present invention provides image definition for an unfixed toner image transferred from the feeding end of the recording material onto the recording material. At least a part of the recording material conveyance path leading to the entrance end of the heat fixing means for fixing the recording material is made into a unit. This is the same as the prior art described above, but In particular, the present invention provides a structure in which the unit body is stepped along a direction substantially perpendicular to the axis of the photoreceptor drum. The fixing device is constructed so that it can be pulled out on different floors, and at least remains on the main body side of the device. The transport unit can be pulled out to a predetermined stage while the rollers remain energized. The point is that it is structured as follows. Incidentally, each of the above-mentioned devices is configured integrally with the transport unit and the paper feed cassette. It may also be configured so that it can be taken out separately from the paper feed cassette. This is a design issue.

[0011]

[Effect]

According to the present invention, since the transport unit is constructed so that it can be pulled out in stages, the All you have to do is pull out the unit according to the desired position, which reduces the operator's work burden and reduces the burden on the operator. In particular, the present invention allows for In other words, while the fuser roller is hidden by the unit, the current status of the fuser roller is Since the state is maintained, it is possible to quickly restart the fixing operation after clearing the jam.

0012 Therefore, the present invention eliminates the need to uniformly turn off the power to the fixing roller when handling jams. As a result, the warm-up time after jam removal can be significantly shortened, allowing for quick printing. The transition to operation becomes possible. Also, if the transport unit is completely removed from the device, the fixing roller should not be energized. In other words, when the fixing roller is exposed, the power is cut off by turning it off. It is easy to ensure safety.

[0013]

【Example】

Hereinafter, embodiments of the present invention will be described in detail based on the drawings. However, this fruit The dimensions, materials, shapes, and relative positions of the components described in the examples are particularly specific. Unless there is a specific description, the scope of this invention is not intended to be limited to only that. This is just an illustrative example. FIG. 1 shows the internal configuration of a page printer according to an embodiment of the present invention. To explain its configuration in detail, this device has a roughly rectangular shape with the operation surface on the right side in the figure. , the photoreceptor drum 1 is disposed approximately in the center thereof, and the rotation direction of the photoreceptor drum 1 is Along the line, there is an exposure optical system 2 at an upper position, a developing device 3 at a right position, a transfer device 4 at a lower position, A cleaning means 5, an eraser 6, and a charger 61 are arranged on the left side, respectively. A known electrophotographic process is performed while rotating the optical drum 1 in the direction of the arrow. It consists of

[0014] Further, below the photosensitive drum 1, the transfer device 4, paper feed cassette 7, etc. are integrated. A built-in transport unit 10 is disposed over almost the entire area inside the device, and the unit The cutter 10 is inserted together with the paper feed cassette 7 through an opening 21 provided on the operation surface side on the right side of the figure. It is structured so that it can be physically pulled out. That is, the transport unit 10 has a paper feed cassette formed over almost the entire bottom area of the apparatus. The sheet storage portion 11 and the upper surface of the storage portion 11 in a substantially tangential direction of the transfer position of the drum 1. It consists of a unit main body 12 along which a conveyance path is formed, and the main body 12 is From the paper feed end of the right cassette 7, the paper feed roller 8 and registration roller are sequentially moved along the conveyance path. roller pair 9, transfer device 4, and conveyance guide 13 extending to the inlet end of the fixing unit 30. , and after bending the terminal end of the conveyance guide 13 downward in a stepped shape. , are connected to the upper wall 111 of the storage section.

[0015] Further, the upper wall 111 of the storage section extends horizontally from the base side of the continuous position to the paper discharge side, and Through the inclined step 112 at the location facing the fixing unit 30, the discharge of the step 112 is performed. It is extended horizontally with the paper side 11a slightly lowered. On the other hand, on the lower surface side of the storage section 11, there is an engagement that can be engaged with an engagement recess 22 provided on the front wall side of the device. A mating protrusion 113 is provided so that when the transport unit 10 is pulled out, the unit 10 is placed in an intermediate position. It is configured so that it is locked in place.

[0016] Further, a paper feed cassette 7 is removably installed in the storage section 11, and the paper feed cassette 7 With the transport unit 10 attached to the main body of the device, or with the transport unit 10 attached. After it is removed, the paper feed cassette 7 can be taken out from the transport unit 10 as shown in FIG. This makes it possible to facilitate paper feeding or cassette replacement.

[0017] On the other hand, the fixing unit 30 includes a pair of fixing rollers 31 and its exit side, as will be explained in detail later. and a pair of paper ejecting rollers 32 disposed on the downstream side of the fixing unit 30. By switching the switching lever 23, the recording material after fixing the image is moved to the inversion guide 2. 4 to the top side of the device, and to the paper output tray 25 provided on the left side wall of the device. It is configured so that paper can be selectively used.

[0018] In addition, the main body of the device, including the reversing guide 24, passes from the left side wall through the paper ejection section on the top of the device. A housing portion 26 (not shown) extending from the upper surface of the developing device 3 to the upper wall of the device is provided on the paper discharge side. The toner in the developing device 3 can be divided and opened around the fulcrum of the - Replacement and clearing of jams inside the paper ejection guide 13 are facilitated. In this case, the developing device 3, photoreceptor drum 1, and fixing unit 30 are all The weight burden of the housing part 26, which is split open to take a configuration that remains on the body side, is reduced. There is no risk of toner scattering or exposure of the heat roller portion 31a of the fixing roller. stomach.

[0019] Next, the fixing unit 30 and the transport unit 10, which are the main components of the present invention, are fitted/disconnected. Explain the structure. First, as shown in FIG. 3, the transport unit 10 is set to be slightly larger than the width of the unit main body 12, so that the edge of the upper wall 111 of the storage section is It is formed so as to be able to face the lower end sides of both axial end walls 33 of the fixing unit 30 . On the other hand, the fixing unit 30 is pivotally supported between the both end walls 33 as shown in FIG. 3(a). It has a heat roller 31a and a pressure roller 31b that rotates in synchronization with the heat roller 31a. , the pressure roller 31b is connected to the heat roller 31 via the swing mechanism 34 on the shaft end side. It is configured to be able to swing in a direction toward and away from a.

[0020] That is, the swing mechanism 34 engages with the shaft of the pressure roller 31b and rotates around the fulcrum 351. A lever member 35 that pivots in the direction of coming into contact with and separating from the heat roller 31a, and The lever member is disposed between the lower surface of the bar member 35 on the roller outlet side and the bottom surface of the unit. A press spring 36 that applies an elastic force upward to the lever member 35; It extends along the lower surface side and swings around a fulcrum 371 provided at the lower end on the entrance side of the fixing unit. an operating lever 37 that moves, and is engaged between the right end side of the operating lever 37 and the end wall 33; By swinging the actuating lever 37 counterclockwise, pressure is applied via the lever member 35. A separation bar applies elastic force in a direction to separate the roller 31b from the heat roller 31a. The other end side of the operating lever 37 extends beyond the lower surface of the fixing unit 30. and extends to the protrusion position 112 on the upper wall 111 of the paper feed storage section, and a roller 39 is installed at the free end of the protrusion 112. is pivotally supported, and the storage section upper wall 111 is configured to be relatively movable. Further, a switch means 40 is attached to the end wall 33 of the fixing unit 30 at the rotational position of the operating lever 37. In other words, when the operating lever 37 is rotated by a predetermined angle or more, it is completely free. The heat roller 31a is configured to be able to turn off the power supply when the heat roller 31a reaches the above state.

[0021] Next, the operation of this embodiment will be explained. First, when performing a predetermined electrophotographic operation, the paper feed roller 8 is After reversing and feeding the recording material from the paper feed storage section 11 to the start end of the conveyance path using the It is made to wait at the entrance end of the stroller 9. On the other hand, on the photosensitive drum 1 side, the latent data written by the exposure optical system 2 is After the image is visualized by the developing device 3, the register is removed in synchronization with the starting edge of the toner image. The recording material that is waiting at the entrance end of the roller 9 is guided to the transfer position, and the unfixed toner image is transferred. After copying, the recording material is inserted into the fixing roller pair 31 via the conveyance guide 13, After the image is fixed, the sheet is guided to a discharge roller 32. Then, when performing page alignment, switch the switching lever 23 to the lower side and reverse the paper ejection guide. 24 to the top side of the device, and by switching the switching lever 23 to the upper side. The paper is then discharged onto the paper discharge tray 25 with the toner image facing upward.

[0022] When replacing the recording material, remove only the paper cassette 7 as shown in Figure 2. If a jam occurs during the recording operation, the transport unit 10 By pulling out the unit, the engaging protrusion 113 on the bottom side of the unit is first installed on the front wall side of the device. The conveyance surface to the transfer position is pulled out by engaging with the engagement recess 22, and the transfer surface is pulled out, and the You can remove any jam that may be present. If the jam occurs further back, move the unit 10 slightly upwards. The entire unit 10 can be taken out by lifting it and pulling it out further. In this case, if a part of the recording material is caught in the fixing roller pair 31 Also, the pressure contact between the pair of rollers 31 is released in conjunction with the unit pulling out operation. Ru.

[0023] That is, the control operation of the fixing unit will be explained in detail based on FIG. First, when the transport unit 10 is installed, the operation of the fixing unit 30 is The movable lever 37 resists the elastic force of the pressure contact spring 36 by the surface of the upper wall 111 of the storage portion, and presses the spring 36. Since the lever member 35 is maintained in the direction of pulling the heat roller 31 It can be rotated in the pressure welding direction of a, and the pressure welding can be done using the pressure welding spring 36 on the outlet side. The roller 31b can be brought into pressure contact with the heat roller 31a. (See (a))

[0024] On the other hand, when the unit 10 is pulled out in this state, the operating lever is activated in conjunction with the pull-out operation. -37 free end drops to the paper discharge surface 114 side of the upper wall of the storage section through the inclined step part 113 Then, the operating lever 37 is rotated counterclockwise by the biasing force of the separation spring 38. The pressure roller 31b is separated via the lever member 35, and one end of the recording material is fixed. Even if a jam occurs while being held between the rollers 31 and Since the recording material is free from the fixing roller 31, it can be easily taken out. In addition, in order to release the thermal contact of the jammed paper, the paper can be passed through the fixing roller 31. There is no risk of fire even if the power is turned on, and toner will not stick to the fixing roller 31 side. It can be prevented. In this state, the operating lever 37 is at the position where the switch means 40 is turned OFF. Since the heat roller 31a is not rotating, the heat roller 31a continues to be energized.

[0025] Therefore, by reinstalling the conveyance unit 10 after jam removal in this state, , the pressure roller 31b is pressed against the heat roller 31a side in the opposite manner to the above operation, and the Since the heat roller 31a remains energized, it is possible to quickly resume the fixing operation. It is Noh.

[0026] Further, the actuation lever 37 of the fixing unit 30 is completely turned off when the transport unit 10 is completely turned off. By detaching from the actuating the switch means 40 in that rotational position in order to be able to Actual maintenance can be carried out by turning off the power to the heat roller 31a. At times, the energization of the roller is prevented, making it easy to ensure safety.

[0027]

[Effect of the idea]

As described above, the present invention is safe and secure even when the fixing roller is kept energized. The transport unit can be reliably pulled out along the recording material transport direction. It is possible to quickly resume recording operation after clearing a jam, and the fixing roller Even if the pair is left on the device main body side, the burden on the operator does not increase. Jam disposal can be done safely and easily. It has various effects such as

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an electrophotographic apparatus according to an embodiment of the present invention.

[Fig. 2] A schematic diagram showing the relationship between the transport unit and the paper feed cassette built into the device.

[Fig. 3] Enlarged views showing the functions of the fixing unit and the transport unit, (a) with the transport unit installed, (b)
indicates that the transport unit is being taken out.

[Explanation of symbols]

30 Fusing unit 10 Transport unit 34 Swing mechanism 40 Switch means

Claims (1)

[Scope of utility model registration request] 1. At least a portion of a recording material transport path from a recording material feeding end to an inlet end of a thermal fixing means for fixing an unfixed toner image transferred onto the recording material is unitized,
The unit body is constructed so that it can be pulled out in stages along a direction substantially perpendicular to the axis of the photosensitive drum, and the conveyance unit is moved to a predetermined stage while maintaining the energized state of at least the fixing roller left on the apparatus main body side. An electrophotographic device characterized by being configured so that it can be pulled out.