JPH04329559A - Image forming device - Google Patents

Abstract

PURPOSE:To make it possible to check only an electrical equipment and to change specification from the outside and while the electrical equipment for an image forming device is conventionally housed in a main body, so that it is impossible to check the electrical equipment and to change the specifications unless an inner machine mechanism part is disassembled, and it is necessary to assemble the machine mechanism part again after checking the electrical equipment, so this is wasteful of man-hour. CONSTITUTION:A recessed part is installed under a base plate 1a for an image forming device main body 1, and a printed circuit board 4 is stored in the recessed part. The printed cirucit board 4 is mounted on a cover 5, and the cover 5 can be attached/detached to/from the recessed part.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to arrangement and mounting means for electrical components of an image forming apparatus.

0002

[Prior Art] Conventionally, electrical components have been placed inside an exterior cover ring inside a device or in an internal unit.
It is configured to connect these with bundled wires. In addition, personal image forming apparatuses are becoming smaller and more densely packed, and in some cases the power supply and control circuits are installed in one place inside the apparatus.

0003

However, in the conventional example described above, circuit checks and adjustments may be required during maintenance, repair, and manufacturing. At this time, the electrical equipment built into the device must be dealt with by removing the outer cover ring or other internal units. For this reason, other unnecessary work is performed in order to perform the original electrical response, which results in a lot of time loss.In addition, when reassembling to the original state, you may forget to install parts, or you may forget to attach screws. Simple mistakes such as forgetting things or installing parts incorrectly can cause malfunctions or breakdowns of the machine.

[0004] Furthermore, in small machines, high-density packaging is progressing, and it is difficult to check the circuits simply by removing the cover ring, etc., and if a failure occurs, the entire electrical unit has to be replaced. . However, in order to replace the electrical unit, other internal parts and units must be removed, so nearly half of the mechanical device must be disassembled, and even when replacing or repairing the electrical unit, It requires a lot of man-hours. Since the operation is checked after completely reassembling the assembly, there are problems such as if there is an assembly error or operation adjustment defect, it is necessary to start over again.

[0005] Furthermore, when manufacturing a device, there are many differences in power sources not only in Japan but also overseas, and it is required for functionality to accommodate these differences. In conventional machines, electrical units are assembled during the manufacturing process, but with this method, it is necessary to organize the assembly configuration depending on the destination. In this case, there are problems such as reconfiguring the line due to changes in the assembly process.

[0006] As personal devices become more densely packed, power sources, high voltage generating circuits, and drive circuits generate heat. This heat is transmitted to the inside of the machine and to the process cartridge, etc., which dislike heat, and has an adverse effect on the photosensitive drum, toner, etc. Because the electrical components are assembled in a narrow space, the heat generated by the electrical components causes the temperature inside the machine to rise.

[0007] In order to suppress this, measures have been taken to suppress the temperature rise inside the machine by inserting heat insulating materials and installing heat shielding walls, but this has resulted in problems such as making the structure more complicated and causing an increase in costs. be. On the other hand, the exterior cover has conventionally been composed of a plurality of cover rings, and when the cover is removed, the internal electrical circuits etc. can be accessed to some extent. However, in recent years, due to miniaturization and cost reduction, efforts have been made to integrate as many covers as possible to reduce the number of parts. In this case, other mechanical parts may be attached to the cover due to functional reasons, and the machine cannot be operated unless the machine including the cover ring is assembled, making it impossible to check the internal circuits, etc. There is a problem.

[0008]Furthermore, in the image forming apparatus, there are cases in which additional functions or expanded functions such as applications are added later, and in order to accommodate this, circuits are added to the electrical equipment section,
It may be necessary to replace the control unit, such as the ROM. At this time, taking out the electrical components and attaching and detaching other mechanisms and units to add functionality takes time, and there is a possibility of mistakes in attaching and detaching. It was difficult.

It is also known that the friction coefficient of the surface of paper feed rollers and paper handling members decreases at low temperatures, and it is not possible to feed paper uniformly over a wide temperature range from low to high temperatures in the usage environment. It is difficult to guarantee performance. On the other hand, there are various types of paper sheets used in image forming devices, from thin paper to thick paper, and recently, recycled paper has been used from the perspective of resource conservation. It is indeed difficult to satisfy all the conditions for the paper feeding roller during paper feeding because the surface properties and the coefficient of friction of the paper change depending on the temperature. Conventionally, in response to this condition, we specified the paper type that can be fed by the image forming device, and selected a roller material that was as stable as possible against temperature changes.
The cost increase was unavoidable.

0010

[Means for Solving the Problems] According to the present invention, a part of the lower base member which is the casing of the image forming apparatus is formed into a concave shape,
By making it possible to attach an electrical unit to the lower side, the electrical unit is held by the electrical equipment holding member and also serves as a part of the exterior cover, making maintenance easier.
This is intended to improve repair and assembly efficiency, to allow the unit to be attached and detached regardless of the specifications of a wide variety of products or to the type of power source, and to suppress performance degradation when the paper feed section is at low temperatures.

A first aspect of the present invention is an image forming apparatus characterized in that an electrical component can be attached to the bottom of the image forming apparatus from the outside.

[0012] According to the second aspect of the present invention, the electrical components including the control section and the power supply section of the apparatus are configured according to specifications and destinations, and all of the electrical components are connected to a common main body of the image forming apparatus. The image forming apparatus according to the first aspect of the present invention is characterized in that the image forming apparatus is detachably installed in the image forming apparatus.

[0013] According to a third aspect of the present invention, the member for holding the electrical component also serves as a part of the exterior and bottom cover ring,
The first device is characterized by being provided with a pedestal for placing the device.
The image forming apparatus according to the invention or the second invention.

The fourth invention of the present invention is characterized in that the electrical equipment section is provided below the paper feeding section.
The image forming apparatus according to any one of the inventions.

The fifth invention of the present invention is characterized in that the paper sheet placement surface of the paper feeding section and the member serving as the paper feeding guide are formed integrally with the base plate of the main body of the image forming apparatus.
This is an image forming apparatus according to the invention.

[0016] The sixth aspect of the present invention is any one of the first to fifth aspects, characterized in that the cover provided with the electrical components can be moved in and out in the lateral direction of the main body of the image forming apparatus. 1 is an image forming apparatus according to one embodiment.

[0017] The seventh invention of the present invention is characterized in that an electrical component is attached to the outside of the main body of the image forming apparatus, and a cover covering the electrical component is detachably attached. The image forming apparatus according to any one of the inventions.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a longitudinal sectional view of an image forming apparatus that best represents the features of the present invention. In the figure, a process cartridge 2 is installed in a main body 1 which is the image forming apparatus.

The process cartridge 2 is a photosensitive drum 2a.
It is equipped with a primary charger, a developer, a cleaning device, etc. for performing an electrophotographic process around the photosensitive drum 2a.
Toner 2b is stored in the hopper of the developing device, and when the process cartridge 2 is installed in the main body 1, the transfer roller 10 provided on the main body 1 side and the photosensitive drum 2a are arranged opposite each other in the transfer section, and the optical The window looks into an optical device 17 that scans an original image on an original platen 16, which is configured to reciprocate in the direction of arrow A in the figure.

During main image formation, the paper sheets 11 placed on the paper feed tray 12 and the paper sheet stacking surface 1c are separated into one sheet by the nip formed by the separating member 7 which is urged toward the upper part of the paper feed roller 3. Paper is fed one by one. The leading end of the paper sheet 11 is sent to the registration roller 8, where it forms a loop and waits. The process cartridge 2 receives an image input from the document on the document table 16 through the optical device 17 and forms the image on the photosensitive drum 2a. As a result, a latent image is formed on the photosensitive drum 2a that is uniformly charged by the primary charger, and then a real image is formed on the photosensitive drum 2a by supplying toner 2b from the developing device.
Form on top. Here, the sheet of paper 11 waiting for the registration roller 8 comes into contact with the photosensitive drum 2a at the same timing as the photosensitive drum 2a. Thereafter, the toner is transferred onto the sheet 11 at the nip between the transfer roller 10 and the photosensitive drum 2a, and the sheet is transported downstream. Furthermore, it has a series of paper conveyance paths through which the toner image on the paper sheet 11 is fixed and fixed by a fixing device 9 and then ejected. On the other hand, residual toner remaining without being transferred to the photosensitive drum 2a is removed by a cleaning device 18.

A base plate 1a, which is a part of the main body 1 and is a lower casing, is provided with rubber feet 1b. A cover 5 covering the electrical equipment covers the printed circuit board 4 from below. The cover 5 is provided with a rubber base 5b that supports the main body 1 together with rubber feet 1b.

In the same figure, a base plate 1a, which is located at the bottom of the main body 1 and which fixes and positions each unit, is located along the paper feed roller 3 and the registration roller 8 at the paper feed section position, and further along the paper sheet stacking surface. It also serves as 1c. Further, nearer to the process cartridge 2 than the paper feed roller 3, the base plate 1a also serves as a paper guide 1d.

In this configuration, the lower right outer side of the base plate 1a becomes a space. Here, a printed circuit board 4 equipped with circuits and electrical components for power supply, sequence control, motor drive, high voltage generation, etc. of the image forming apparatus can be accommodated, and the components installed in the electrical circuit include: There are parts that generate heat, and there are also elements that require heat dissipation. A heat sink 4a is provided on the printed circuit board 4 to perform this heat radiation. The printed circuit board 4 of the electrical equipment section is attached and supported by a cover 5 that covers the electrical equipment part and serves as an external surface and is attached to the image forming apparatus main body 1. Further, if necessary, the cover 5 is provided with louver holes 5a for ventilation necessary for cooling the AC cord 4b and the heat sink 4a.

A cover 5 that accommodates electrical components in the recessed portion at the lower right of the base plate 1a and covers the electrical components also serves as part of the exterior and bottom covering. That is, the cover 5 has a side plate 5d.
, 5e are provided, and there are no front and rear end plates on both sides. The front and rear exteriors of the main body 1 (parallel to the plane of the paper in FIG. 1) hang down to the lowest level of the base plate 1a, and the lowest edges of the front and rear surfaces of the main body 1 are straight. The cover 5 fits into the front and rear hanging parts of the exterior of the main body 1, the side plate 5e fits between the hanging walls 1f and 1g hanging from the base plate 1a, and the side plate 5d fits between the hanging walls 1f and 1g hanging from the base plate 1a.
It is designed to sit on the bottom of the recess. When the cover 5 is attached to the main body 1, holes that coincide with the louver holes 5a are provided in the hanging walls 1f and 1g.

Printed circuit board 4 attached to cover 5
When installing to the image forming apparatus, insert the small screw 6 through the mounting hole 5c of the cover and install the female screw 1 in the base plate 1a.
It is fixed by screwing into e.

[0026] When the electrical component is installed and is in a state of normal operation, the electrical component begins to generate heat as soon as electricity is applied. Next, the heat warms the paper feeding roller 3, the sorting member 7, the paper stacking surface 1c, the guide 1d, and the paper 11 via the base plate 1a. The paper feeding roller 3 and the separating member 7 are made of a rubber-based material, and their surfaces have a friction coefficient set in advance so that the paper sheets 11 can be fed appropriately. However, it is known that as a characteristic of rubber material, the hardness increases and the surface friction coefficient decreases at low temperatures compared to high temperatures. For this reason, there is a difference in the paper feeding performance of the paper feeding unit, such as the handling force and paper feeding force, between low temperature and high temperature environments.In particular, at low temperatures, the handling performance decreases and the sheets are fed one by one. Two or more sheets are fed when they should be, and this causes problems such as jams in the conveyance path, poor transfer, and poor fixing. Here, as in the present invention, paper feeding failures under low temperature conditions can be improved by heating the rubber material part with the heat of the electrical equipment under low temperature conditions.

``Embodiment 2'' FIG. 2 shows a sectional view of the second embodiment. In the figure, a heat sink 4a and an AC cord 4b are attached to the printed circuit board 4. It is attached to the base plate 1a of the main body 1 with machine screws 13. At this time, the land portion of the circuit pattern of the printed circuit board 4 is provided on the lower surface, and a pattern portion for checking the circuit is also provided. The cover 5 is fastened with machine screws 6 so that the cover can be attached and detached by itself. According to this configuration, by removing the cover 5 and attaching it to a separately provided circuit inspection jig, the presence or absence of defects can be automatically checked, which not only simplifies the process on the production line, but also enables service and Even during maintenance, the presence or absence of a malfunction can be easily checked without disassembling the main body 1. In addition, since the mounting surface of electrical components is on the upper side, the components can be protected and reliability can be improved.

Embodiment 3 FIG. 3 is a longitudinal sectional view of the third embodiment, and FIG. 4 is a side view of FIG. The electrically mounted electrical components including 4b are attached to the cover 5. This cover 5 is provided with two rails 14 for supporting guides, and a guide rail 15 that fits with the rails 14 is provided at a hanging portion of the base plate 1a of the main body 1. The machine screws 6 pass through the cover 5 at the louver portion and are screwed into screws 1e provided on the base plate 1a. According to the present invention, the electrical component can be slid to the right by simply removing the machine screws 6 as needed, and can be attached and detached. Therefore, there is no need to stand the main body 1 vertically when attaching or removing the electrical unit, and corrections, maintenance, and addition of extended functions such as applications can be done from the top of the main body 1. In addition, if you use a slot type card edge connector, there is no need to do any wiring such as bundled wires with the main body, and the wiring connection can be completed just by installing it. Further, in some cases, if a flexible flat cable is used, there is an advantage that operation can be checked even when the electrical equipment is pulled out. In this embodiment, the cover 5 can be moved in and out from the left and right sides of the figure, but it may also be made so that it can be moved in and out in the front and rear directions.

In each of the above embodiments, the electrical components, including the control section and power supply section of the device, are configured by specification, country of destination, and region, and are removably installed in the main body of a common image forming device. It is also possible to increase the efficiency of mixed flow production, and dividing production lots into flow production does not require special changeover preparation time.

[0030]

[Effects of the Invention] As explained above, by making it possible to attach the electrical component to the bottom of the image forming apparatus from the outside, maintenance and adjustments can be easily performed, reducing work time loss. . Additionally, the effort required for assembly and disassembly can now be kept to a minimum, eliminating anxiety caused by work errors. Further, since the electrical equipment section is located outside, heat buildup inside the image forming apparatus is reduced.

[0031] Furthermore, by making only the electrical parts removable from the main body, it is now possible to install electrical parts that match AC power sources that vary by region not only in Japan but also overseas, making it possible to divide or switch conventional production lines. Previously, the main body could be assembled on the same line and installed according to specifications during the completion process, resulting in fewer setups, labor savings, and economics in the product production line configuration.

[0032] Furthermore, by having the cover that holds the electrical component also serve as a covering ring and by providing a pedestal, the number of parts can be reduced, resulting in space savings and cost reductions.

[0033] In addition, by being able to easily remove a part of the covering ring and the cover, serviceability and maintainability have been improved, and when adding functions or extended functions such as applications, it is easier to attach and detach electrical equipment. This simplifies the work as additions and replacements can be made without having to do anything.

[0034] In addition, by heating the paper feeding section using the heat of the heating element of the electrical equipment, it is possible to stabilize paper feeding in low temperature conditions, and by warming the paper sheet, it is possible to preheat before transfer. As a result, it is possible to suppress thermal shock during fixing and to reduce shrinkage of the image after paper ejection, which is effective in reducing paper curl and paper shrinkage rate, which improves paper feeding performance. There are advantages such as improved performance and improved image quality. In particular, since the base plate is used as a member constituting the paper sheet placement surface of the paper feed section and the paper guide, heat transfer to the electrical components is good.

[0035] If the cover with electrical components can be moved in and out laterally, the electrical components can be inspected or replaced without having to stand up the image forming apparatus.

[0036] If you install electrical components on the outside of the main body and cover them with a cover, you can inspect the electrical components simply by removing the cover.
This makes maintenance possible and is particularly advantageous for circuit checks.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of an image forming apparatus embodying the present invention.

FIG. 2 is a longitudinal sectional view of an image forming apparatus showing a second embodiment.

FIG. 3 is a longitudinal sectional view of an image forming apparatus showing a third embodiment.

FIG. 4 is a right side view of FIG. 3;

[Explanation of symbols]

1 Main body 1a Base plate 1b Rubber feet 1c Paper sheet loading surface 3 Paper feed roller 4 Printed circuit board 4a Heat sink 4b AC code 5 Cover 5a Louver hole 5b Pedestal 5c Mounting hole 6 Machine screw 8 Registration roller 13 Machine screw 14 Rail 15 Guide rail

Claims (7)

[Claims] 1. An image forming apparatus characterized in that an electrical component can be attached to the bottom of the image forming apparatus from the outside. [Claim 2] The electrical equipment section includes electrical components including a control section and a power supply section of the apparatus, and is configured by specification and destination, and all of the electrical equipment sections are removably installed in a common image forming apparatus main body. The image forming apparatus according to claim 1, characterized in that: 3. The image forming device according to claim 1 or 2, wherein the member holding the electrical component also serves as part of the exterior and bottom covering, and is provided with a pedestal for placing the device. Device. 4. The image forming apparatus according to claim 1, wherein the electrical equipment section is provided below the paper feed section. 5. The image forming apparatus according to claim 4, wherein the paper sheet placement surface of the paper feeding section and a member serving as a paper feeding guide are formed integrally with a base plate of the image forming apparatus main body. . 6. The image forming apparatus according to claim 1, wherein the cover provided with the electrical components can be moved in and out laterally of the image forming apparatus main body. 7. The image forming apparatus according to claim 1, wherein the electrical equipment is attached to the outside of the main body of the image forming apparatus, and a cover covering the electrical equipment is detachably attached. Forming device.