JPH0310941B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an electrophotographic apparatus in which the main body is separated into an upper mechanism and a lower mechanism, and the upper mechanism can be opened for maintenance or the like.

In electrophotographic apparatuses, a device as shown in FIG. 1 is used to remove paper jams during copying or to improve operability during maintenance.

In this apparatus, a main body 10 includes a photoreceptor drum 11, a charging device 12 which is an image forming means provided around the photoreceptor drum 11, an exposure device 13,
The upper mechanism 10a, which includes the developing device 14, the cleaning device 16, etc., is rotated in the direction of arrow S to open the upper part of the main body 10 for maintenance. In addition, if a paper jam occurs in the conveyance device 23, the conveyance path 23 of the transfer paper 22, which can be rotated in the direction of the arrow,
a upper guide plate 24, which is an upper conveying element at the upper part;
Alternatively, the upper conveyance roller 26 and further the upper fixing roller 27 are rotated as shown by solid lines in FIG. 1 to remove paper jams.

However, in this device, after maintenance of the conveyance device or paper jam removal is completed, it is forgotten to return the upper conveyance elements such as the upper guide plate 24 to the conveyable state shown by the dotted line in FIG.
The operator often makes an operational error of closing the door in the opposite direction to the arrow S direction. As a result, each device housed in the upper mechanism 10a comes into contact with the upper conveying element, causing a problem in that one of them is damaged and must be replaced.

This invention was made based on the above circumstances, and after maintenance etc. is completed and before the upper mechanism is closed, the plurality of upper conveying elements are reliably returned to a conveyable state.
It is an object of the present invention to provide an electrophotographic apparatus which is not damaged due to abutment between each device of an upper mechanism and an upper conveyance element, and which has good operability and high reliability.

Hereinafter, prior to describing embodiments of the present invention, the configuration and operation of a normal device will be described with reference to FIG. 2, which is a reference example. The main body 28 is separated into an upper mechanism 28a and a lower mechanism 28b, each of which includes a photoreceptor drum, image forming means, etc. (not shown).
A paper feed cassette 31 for storing transfer paper 30 as a transfer material is provided at one end of the lower mechanism 28b, and a paper ejection device 32 for receiving the transfer paper 30 with a completed copy image is provided at the other end. . In addition, during copying, a photosensitive drum (not shown) is passed through the transfer paper 30 from the paper feed cassette 31 to the paper discharge device 32.
A conveying device 3 that conveys the transfer paper through a heating fixing roller 37 consisting of a transfer device 33 that comes into contact with the transfer device 33, an upper fixing roller 34 that has a built-in heater 34a, and a lower fixing roller 36 that comes into pressure contact with this during fixing.
8 is provided. The conveyance device 38 includes a first guide plate 40, a first conveyance roller 41, a second
It is composed of a guide plate 42 , a conveyor belt 43 , and a first upper conveyor roller 44 , a second upper conveyor roller 46 , and a third conveyor roller 47 that are in rolling contact with the conveyor belt 43 . Further, among the upper conveyance elements that constitute the upper part of the conveyance path 38a of the conveyance device 38, a second guide plate 42 which is a transfer material guide means is provided.
an upper guide plate 42a, a second upper conveyance roller 46, and an upper fixing roller 3 serving as a fixing means.
4 are formed so as to be rotatable upward, which is the non-guiding position, and are constantly moved from the conveyance path 38a by the first spring 48, the second spring 50, and the third spring 51, which are downward biasing members. The transfer paper 3 is biased toward the lower conveyance element forming the lower part.
Take a guiding position to guide 0. Further, 52 is a paper feed roller. Next, we will discuss the effect. The copying conveyance device 38 is in a state where it can convey the transfer paper 30, and the upper guide plate 42a, the second upper conveyance roller 46, and the upper fixing roller 34 are each urged toward the lower conveyance element side. ing. Then, when copying starts, an image forming means (not shown) is placed on a photoreceptor drum (not shown) in the upper mechanism 28a.
While the toner image is formed by the upper mechanism 28
The transfer paper 30 is conveyed in b, and after the toner image is transferred from the photoreceptor drum by the transfer device 33,
The copy image is fixed by the heat fixing roller 37 to complete the copy image, and then the paper is discharged to the paper discharge device 32. However, if a paper jam occurs during copying, the operator stops the apparatus and then rotates the upper mechanism 28a in the direction of arrow U to open it. Next, depending on the location where the paper jam occurred, the upper guide plate 42a, the second upper conveying roller 46, or the upper fixing roller 34 is moved to the first
The spring 48, the second spring 50, or the third spring 51 is rotated in the direction of arrow v to the position shown in FIG. After removing the jammed transfer paper 30, when the user releases his/her hand, each upper conveyance element is biased by a spring and automatically returns to the conveyable state. After this upper mechanism 2
Closing 8a makes the device capable of copying again.

With this configuration, even if the upper conveying element is moved to the upper non-guiding position during maintenance of the conveying device 38 or when a paper jam occurs, it will automatically return to the original guiding position as soon as you release your hand. This prevents accidents such as forgetting to return the upper conveying element and causing damage due to each device inside the upper mechanism 28a coming into contact with the upper conveying element when the upper mechanism 28a is closed.

Next, an embodiment of the present invention will be described with reference to FIGS. 3 and 4. Note that the same parts as those in the reference example shown in FIG. 2 are given the same reference numerals, and the explanation thereof will be omitted. an upper guide plate 42a, which is a transfer material guide means rotatably formed to assume a guiding position and a non-guiding position; a second upper conveying roller 46;
A first lever 53, a second lever 54, and a third lever 56, which are first engaging means, are located at the center of rotation of the upper fixing roller 34, which is a fixing means.
is fixed. Further, on the side wall of the upper mechanism 28a, a first protrusion 57 and a second protrusion are provided, which are second engagement means that abut the first lever 53, the second lever 54, and the third lever 56, respectively. Section 58,
and a third protrusion 60 are formed.

When performing maintenance on the conveyance device 38 or removing paper jams, the operator rotates the upper mechanism 28a in the direction of arrow w as shown in FIG. 4, releases it, and then rotates each lever in the direction of arrow x. , the upper guide plate 42a, the second upper conveyance roller 46, or the upper fixing roller 34 are rotated in the same direction to the non-guiding position to perform maintenance such as cleaning or to remove paper jams. After this, each lever may be returned to its original position by hand, but even if the levers are not returned to their original positions, if the upper mechanism 28a is closed in the direction opposite to the arrow W direction, the first protrusion 57, the first protrusion 57, The second protrusion 58 and the third protrusion 60 abut on the levers of the upper guide plate 42a, the second upper conveyance roller 46, and the upper fixing roller 34, respectively, and press down each lever upon closing. Therefore, the upper guide plate 42a, the second upper conveying roller 46, and the upper fixing roller 34 are automatically returned to the guiding position where the transfer paper 30 can be conveyed.

With this configuration, after maintenance etc.
Even if you forget to return each upper conveyance element, each upper conveyance element is automatically returned to a conveyable state when the upper mechanism 28a is closed, so that each device in the upper mechanism 28a and the upper conveyance element will come into contact and be damaged. This accident will be prevented.

Note that the present invention is not limited to the above-mentioned embodiments, and can be modified in various ways. For example, the upper conveyance element may be another conveyance roller or a guide plate, or the fixing device may be in the form of a heater plate. good. In addition, as in the first modification shown in FIG.
A fourth spring 61, a fifth spring 62, and a sixth spring 63, which are upward biasing devices, are attached to the first lever 53, second lever 54, and third lever 56, which are engagement means. For example, the upper mechanism 28
At the same time as a is opened, each upper conveying element is automatically rotated to the upper non-guiding position, and when the upper mechanism 28a is closed, the upper conveying element is automatically returned to the guiding position by the protrusion that is the second engagement means. It will be done. Therefore, during maintenance or the like, there is no need to open and close the upper conveying element separately from the upper mechanism 28a, and operability is further improved. Moreover, the return amount of the upper conveying element can be adjusted by the degree of engagement with the second engaging means, and the upper conveying element can be positioned at an appropriate guide position.
The accuracy of conveyance is also improved. Furthermore, the mechanism for automatically opening and closing the upper conveyance element is optional, and as in the second modification shown in FIG. A recess 66 is formed into which the tip of each lever such as the first lever 53 serving as the first engagement means can be inserted, and when the upper mechanism 28a is opened, the lever tip is pushed up at the bottom of the recess 66 as shown in FIG. The upper conveying element may be rotated upward, and when the upper mechanism 28a is closed, the tip of the lever may be pushed up at the upper bottom of the recess 66 to return the upper conveying element, as shown in FIG. 6A.

As explained above, according to the present invention, a biasing member that constantly biases the upper conveying element downward is provided, or a first engaging means attached to the upper conveying element is connected to a second engaging means provided on the upper mechanism. By pressing down with the coupling means, the upper conveying element that has been rotated during maintenance etc. can be automatically returned to its original position. This eliminates the need for the operator to return the upper conveying element before closing the upper mechanism. Improved operability.
Furthermore, since the upper conveying element is reliably returned when the upper mechanism is closed, there is no accident in which a device inside the upper mechanism and the upper conveying element come into contact with each other and one of them is damaged, thereby improving reliability. Since the conveyance element is reliably positioned at the guide position, paper jams can be prevented and a stable image can be obtained from the image forming means on the transfer material. In addition, it makes it easier to perform maintenance or troubleshoot paper jams, etc.
It has excellent operability without fear of erroneous operation, and the transfer guide means and roller means are precisely positioned to prevent paper jams in the transfer material conveyance path to the transfer section and the transfer material conveyance path to the fixing section. The transfer material can be reliably conveyed to the transfer section and the fixing section.

Furthermore, if configured as in the first modification or the second modification, the operator can position the upper conveyance element at the guide position by opening and closing the upper mechanism, which improves operability, conveyance accuracy, and image forming process. Accuracy can be improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional device, FIG. 2 is a sectional view showing a lower mechanism as a reference example of the present invention, and FIGS. 3 and 4 show an embodiment of the present invention, and FIG. 3 is an upper part thereof. 4 is a sectional view showing the mechanism in a closed state, FIG. 4 is a sectional view showing the upper mechanism and the upper conveying element in an open state, FIG. 5 is a sectional view showing the lower mechanism of the first modification of the invention, FIG. 6 is a side view showing a protrusion of a second modification of the invention. 28a... Upper mechanism, 28b... Lower mechanism, 3
0... Transfer paper, 31... Paper feed cassette, 32...
Paper discharge device, 33... Transfer device, 34... Upper fixing roller, 37... Heat fixing roller, 38... Conveying device, 42a... Upper guide plate, 46... Second upper conveying roller, 48... first spring, 5
0...Second spring, 51...Third spring, 53...First lever, 54...Second lever, 56...Third lever, 57...First protrusion, 58 ...Second protrusion, 60...Third protrusion, 64...Protrusion, 66...Recess.

Claims (1)

[Scope of Claims] 1. An upper mechanism having an image carrier and an image forming means provided near the image carrier, a transfer section, a fixing section, and a transfer material guide means for conveying the transfer material to the transfer section. and a lower mechanism having a conveyance path consisting of a roller means for conveying the transfer material conveyed from the transfer section to the fixing section, and the upper mechanism can be opened and closed with respect to the lower mechanism. In the photographic apparatus, the transfer material guide means includes a first guide means fixedly provided along the conveyance path;
A direction along the opening/closing direction of the upper mechanism, which is arranged opposite to the guide means of the upper mechanism, between a guide position where the transfer material conveyed on the conveyance path can be conveyed and a non-guidance position different from this guide position. and a second guide means provided so as to be openable and closable, and the roller means is configured to take a guiding position for guiding the conveyed transfer material and a guided position different from this guiding position. The second guide means and the roller means each have abutted portions, and the upper mechanism includes a second guide means that can be opened and closed in a direction along the opening and closing direction of the second guide means. A first contact portion that contacts the abutted portion and a second contact portion that abuts the abutted portion of the roller means are provided, and the upper mechanism is in an open state with respect to the lower mechanism. At one time, said second guide means and said roller means are moveable to said non-guiding position by manual operation, and when said upper mechanism is closed relative to said lower mechanism; The first and second contact portions contact the non-contact portions of the second guide means and the roller means, respectively, so that the second guide means and the roller means are in the non-guide position. An electrophotographic device characterized by automatically moving from a position to a guiding position.