JPH11133840A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure the maintenance of parts whose heat resistant temperature is low even when a heating part is stopped in a heat accumulated state by enabling a cooling means driven with the driving means of an image forming device to act cooling action even after the driving means is stopped. SOLUTION: A one-way clutch is incorporated in the fixed part of the blade of an auxiliary cooling fan 21. As for the one-way clutch; a direction where the rotational force of a gear 21b and a driving shaft 21a transmitted through a gear train 22 from a driving motor 18 interlockingly driven to be rotated at the time of operating a device main body 1 is transmitted to the fan 21 is a driving force transmitting direction. The rotating direction when the fan 21 is rotated by the intertial force of the fan 21 own when the motor 18 is stopped with the stop of the operation of the main body 1 and the gear 21b and the driving shaft 21a meshed with the gear train 22 are stopped is set as a driving non-transmitting direction. Even when the operation of each part of the main body 1 is stopped and a cooling fan 19 and the motor 18 are stopped, the fan 21 continues idle rotation by the action of the one-way cluth so as to continue cooling action.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a cooling mechanism for cooling the inside of an image forming apparatus such as a facsimile machine and a printer.

[0002]

2. Description of the Related Art Inside an image forming apparatus such as a facsimile machine or a printer, a large heat source such as a heat fixing device or a drive motor for heating and fixing a toner image, and an electrophotographic photosensitive member according to image information. A component having a low heat-resistant temperature such as a laser scanner that scans and irradiates a laser beam onto the drum is mounted, and as a means for preventing a rise in the temperature inside the apparatus, for example, as disclosed in JP-A-6-94920 Is provided with a cooling fan that is driven to rotate by driving means such as a motor.

[0003]

However, in the above-mentioned conventional example, the cooling fan is stopped simultaneously with the stop of the apparatus. Therefore, when the print processing speed is increased or the number of prints is increased, the heat fixing device or the like is required. There is a problem that it is not possible to cope with a rise in the temperature of the heat generating portion and a rise in the temperature of the drive portion such as the drive motor.

That is, when continuous printing is performed, when the apparatus stops with the heat generating portion storing heat, the cooling fan also stops at the same time, so that the temperature of the stored heat generating section flows into the apparatus, and the heat is stored in a component having a low heat resistant temperature. There is a risk that this will have an adverse effect.

Further, in the case where components having a low heat-resistant temperature must be arranged in the vicinity of the heat-fixing device due to the structure of the apparatus, the heat-fixing device and the component having a low heat-resistant temperature can be adiabatically separated from each other. In difficult cases, if the cooling means forcibly cools parts with a low heat-resistant temperature, the temperature will be lowered to the ambient temperature of the heating and fixing device. There is a problem that high energy is required to perform the process.

[0006] The present invention is to solve the above-mentioned problems,
The purpose is to reduce the temperature of the heat-generating part by performing the cooling action by the cooling means and lowering the temperature of the heat-generating part by lowering the heat-resistant temperature even when the apparatus is stopped with the heat-generating part storing heat after continuous printing. An object of the present invention is to provide an image forming apparatus which can ensure the maintenance of parts, can save energy, and can reduce the size of the apparatus.

[0007]

A typical configuration according to the present invention for achieving the above object is an image forming apparatus for conveying a sheet to form an image, wherein a driving means of the image forming apparatus is used. An image forming apparatus, wherein the driven cooling means is configured to exert a cooling action even after the driving means is stopped.

According to the present invention, since the cooling means driven by the driving means of the image forming apparatus exerts the cooling function even after the driving means is stopped, the continuous printing is performed after the driving means is stopped. Even if the apparatus is stopped in a state where the heat generating portion stores heat, the cooling means still exerts a cooling function to lower the temperature of the stored heat generating portion, thereby securing the maintenance of components having a low heat-resistant temperature.

When the cooling means is a fan rotated by the driving means via one-way transmission means such as a one-way clutch, the driving means is operated by the one-way transmission means while the driving means is being driven. Is transmitted to the fan, and the fan rotates to exhibit a cooling action,
After the drive means is stopped, the fan is released from the drive transmission system by the action of the one-way transmission means, and idles by the inertia force of the fan itself to exert a cooling function.

In the case where the cooling means is a fan which is driven to rotate by the drive means via a drive / non-drive control means such as an electromagnetic clutch, the drive / non-drive control means is operated while the drive means is being driven. After the drive unit is in the driving state, the rotational driving force of the driving unit is transmitted to the fan, the fan rotates to exert a cooling function, and after the driving unit stops, the driving / non-driving control unit is set in the non-driving state to set the fan Is released from the drive transmission system, and idles by the inertia force of the fan itself to exert a cooling effect.

Further, the cooling means is used for cooling a component having a low heat-resistant temperature, and the component having a low heat-resistant temperature is provided with a detecting means for detecting the temperature of the component. In the case where the ON / OFF of the non-drive control means is controlled, the temperature of a component having a low heat-resistant temperature can be maintained at an appropriate temperature.

Further, when the one-way transmission means or the drive / non-drive control means and the cooling means are integrally formed, the space can be reduced, and the size of the apparatus can be reduced. I can do it.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a facsimile machine as an example of an image forming apparatus according to the present invention will be specifically described with reference to the drawings. FIG. 1 is an explanatory cross-sectional view showing an overall configuration of an image forming apparatus according to the present invention, FIG. 2 is a perspective view showing an arrangement configuration of a cooling unit of a first embodiment of the image forming apparatus according to the present invention, and FIG. FIG. 4 is an explanatory plan view showing the arrangement of the cooling means according to the embodiment, and FIG. 4 is an explanatory side view showing the arrangement of the cooling means according to the first embodiment.

In FIG. 1, reference numeral 2 denotes a document table which also serves as a top cover of the image forming apparatus main body 1;
A plurality of originals D can be stacked thereon.

An image reading unit 3 separates and transports the originals D stacked on the original placing table 2 one by one and reads image information of the originals D. The image reading unit 3 has an LED as a light source
(Light Emitting Diode) A contact image sensor 3a for irradiating light from the array to the image information surface of the original D, forming an image of the reflected light reflected from the image information surface on a sensor element by a lens, and reading image information is provided. I have.

Reference numeral 4 denotes a process cartridge serving as an image forming means. The process cartridge includes a front cassette section 5 provided at a lower portion of the apparatus main body 1 and an MP (multi-paper) cassette section 6 provided at an upper portion thereof. A recording sheet P made of resin or the like is selectively and separately fed one by one by a cassette feeding unit 7 and an MP (multi-paper) feeding unit 8 and provided inside the process cartridge 4. The sheet is sent to an image forming section formed between the photosensitive drum 4a and the transfer charger 9 arranged opposite to the photosensitive drum 4a.

A laser scanner unit 10 emits a modulation signal from a laser beam oscillator 10a of the laser scanner unit 10 based on an image signal output from a control unit 11 that integrates a recording system, an image reading system, and a communication system. Then, the modulated beam is scanned by the rotating polygon mirror 10b, reflected by the return mirror 10c, and irradiated with the scanning light on the photosensitive drum 4a whose surface is uniformly charged by the primary charger 4b to form an electrostatic latent image. Is formed, and the electrostatic latent image is visualized by toner supplied by the developing sleeve 4c to form a toner image.

The photosensitive drum 4a and the transfer charger 9
After the toner image formed on the photosensitive drum 4a is transferred to the recording sheet P sent to the image forming section between the above and the transfer charging device 9, the recording sheet P is conveyed along the conveyance guide 12. After being sent to the heat fixing unit 13 and subjected to heat and pressure processing by the heat fixing unit 13 to be permanently fixed, the discharge tray is transported by the discharge roller pair 14 and provided outside the apparatus.
Exhausted on 15

The toner remaining on the surface of the photosensitive drum 4a is removed by a cleaning blade 4d, and is stored in a waste toner chamber in the process cartridge 4. The photosensitive drum 4a, the primary charger 4b, the developing sleeve 4c and the cleaning blade 4d
And is configured to be detachable from the apparatus main body 1.

The apparatus main body 1 is provided with a cartridge cover 16 connected to the document mounting table 2 and also serving as the document mounting table, which can be opened and closed with respect to the apparatus main body 1. When the cartridge cover 16 is opened, the cartridge cover 16 is opened. The process cartridge 4 can be pulled out of the apparatus main body 1 and replaced.

The cartridge cover 16 is provided with an interlock mechanism (not shown). When the cartridge cover 16 is open or the process cartridge 4 is not set in the apparatus main body 1, the apparatus main body 1 operates. Not to be.

The drum shutter 4e provided in the process cartridge 4 is opened in conjunction with the setting of the process cartridge 4 in the apparatus main body 1. By opening the cartridge cover 16, the process cartridge 4 is opened. When set to 1, the drum shutter 4e is opened, and when the process cartridge 4 is taken out of the apparatus main body 1, the drum shutter 4e is closed to prevent unnecessary exposure, dirt or damage of the photosensitive drum 4a. It has become.

As shown in FIG. 2, a laser scanner unit 10 having parts having a low heat-resistant temperature, a heating unit such as a heat fixing unit 13 serving as a large heat source, and a driving unit such as a driving motor 18 serving as a driving unit are constituted by an apparatus. It is separated by a structure 1a of the main body 1 and is adiabatically separated. Reference numeral 17 denotes a heat radiating portion serving as a duct for releasing heat and water vapor generated from the heat fixing device 13.

On the back side of the apparatus main body 1 of each of the heat radiating section 17 and the heating and fixing device 13, a cooling fan 19 that is rotated and driven in conjunction with the operation of the apparatus main body 1 is provided.
Is rotated to flow an appropriate amount of air into the heat radiating section 17 and the inside of the apparatus main body 1 through the duct 20, thereby suppressing an increase in the temperature of the heating section such as the heat fixing unit 13 and the driving section such as the driving motor 18 to read an image. This prevents problems such as an adverse effect on the section 3 and vapors evaporated from the recording sheet P condensing and dropping on the surface of the recording sheet P.

In FIG. 2 to FIG. 4, reference numeral 21 denotes an auxiliary cooling fan serving as a cooling means. The auxiliary cooling fan 21 faces a cooling fan 19 disposed on the back side of the apparatus main body 1 via a heat radiating section 17.
It is arranged on the front side. A one-way clutch (not shown) serving as one-way transmission means is built in the fixed portion of the blade of the auxiliary cooling fan 21. The auxiliary cooling fan 21 is connected to the drive shaft 21a via the one-way clutch. The gear 21b is fixedly engaged with a part of a gear train 22 connected to each drive unit of the recording system.

An output gear 18b fixed to a drive shaft 18a of a drive motor 18 serving as a drive means of the image forming apparatus A is also meshed with a part of the gear train 22, and is interlocked when the apparatus main body 1 operates. The rotational driving force of the driving motor 18 that is rotationally driven is transmitted to the auxiliary cooling fan 21 via the driving shaft 18a, the output gear 18b, the gear train 22, the gear 21b, the driving shaft 21a, and the one-way clutch. Are driven to rotate.

The one-way clutch transmits to the auxiliary cooling fan 21 the torque of the gear 21b and the drive shaft 21a transmitted via the gear train 22 from the drive motor 18 which is rotated and driven in conjunction with the operation of the apparatus body 1. When the drive motor 18 stops and the gear 21b and the drive shaft 21a meshing with the gear train 22 stop when the operation of the apparatus main body 1 stops, the auxiliary cooling fan 21 is driven by its own inertial force. The rotation direction at the time of idling is set to the non-drive transmission direction.

Since the auxiliary cooling fan 21 rotates for a longer time and can expect a cooling action as the inertia force of the auxiliary cooling fan 21 is larger,
It is preferable to increase the weight and the outer diameter of the fan to increase the moment of inertia. Further, if the cooling fan 19 is configured to rotate in the same direction, the direction of the air flowing into the heat radiating portion 17 and the inside of the apparatus main body 1 becomes the same direction, which is effective.

In the above configuration, when an image signal is input and an image forming operation is started, the cassette feeding unit 7 or M
Each unit of the apparatus main body 1 such as the P feeding unit 8, the process cartridge 4, the heat fixing unit 13, the laser scanner unit 10, etc. operates to generate heat. In particular, the drive motor 18 and the heat fixing unit 13 are large heat sources, and the heat generated here is forcibly released to the outside of the apparatus main body 1 by the cooling fan 19 via the radiator 17 and the duct 20.

When the image forming operation is started, the driving motor
When the 18 rotates, the auxiliary cooling fan 21 also rotates to exert a cooling effect, and continues cooling even during the image forming operation. Then, even if the image forming operation is completed and the operation of each part of the apparatus main body 1 is stopped and the cooling fan 19 and the drive motor 18 are stopped, the auxiliary cooling fan 21 is moved in the same direction by its own inertial force by the action of the one-way clutch. And the cooling action can be continued.

Therefore, after the continuous printing, even if the apparatus main body 1 is stopped in a state where the heat generating portion such as the heat fixing unit 13 stores heat, the cooling operation is still continued by the idling by the inertia force of the auxiliary cooling fan 21. Since the temperature of the heat generating portion that has been exhibited and stored can be effectively lowered, it is possible to ensure the maintenance of components having a low heat-resistant temperature, such as the laser scanner unit 10.

In this embodiment, the auxiliary cooling fan 21
A gear train is provided from a drive motor 18 that supplies a rotational drive force to each part of the recording system of the apparatus main body 1 without providing a dedicated motor.
The configuration in which the rotational driving force is transmitted via the connection 22 is preferable because the number of components can be reduced to save energy and reduce the size of the device, and also reduce the heat source.

In addition, since a one-way clutch (not shown) serving as a one-way transmission means is integrally built in the fixed portion of the blade of the auxiliary cooling fan 21, the space can be reduced, and the size of the apparatus can be reduced. I can do it.

Next, a second embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. FIG. 5 is an explanatory plan view showing an arrangement configuration of a cooling unit of a second embodiment of the image forming apparatus according to the present invention. The same components as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

In the present embodiment, as shown in FIG. 5, in a structure in which the drive motor 18 is disposed at a position substantially opposed to the laser scanner section 10 (see FIG. 2),
Auxiliary cooling fan on the side of the drive shaft 18a opposite to the output gear 18b
21 is provided to cool the laser scanner unit 10 more effectively.

Except for the drive shaft 18a, the drive motor 18 and the auxiliary cooling fan 21 are adiabatically separated by the structure 1a of the apparatus main body 1 (see FIG. 2). The flow into the scanner unit 10 is prevented.

As in the first embodiment, a one-way clutch (not shown) serving as one-way transmission means is built in the fixed portion of the blade of the auxiliary cooling fan 21, and the auxiliary cooling fan is connected via the one-way clutch. 21 is the drive motor 18
Is connected to the drive shaft 18a. Another configuration is the first configuration.
The configuration is substantially the same as that of the embodiment, and a similar effect can be obtained.

In particular, in this embodiment, the auxiliary cooling fan 21
Since the laser scanner unit 10 is directly opposed to the laser scanner unit 10, the laser scanner unit 10, which is a component having a low heat-resistant temperature, can be cooled more effectively, and the maintenance of the laser scanner unit 10 can be ensured.

Next, a third embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. FIG. 6 is an explanatory plan view showing an arrangement configuration of a cooling unit of a third embodiment of the image forming apparatus according to the present invention. The same components as those in the first and second embodiments are denoted by the same reference numerals, and description thereof is omitted.

In the present embodiment, as shown in FIG. 6, in place of the one-way clutch provided in the fixed portion of the blade of the auxiliary cooling fan 21 in the second embodiment, the drive / non-drive control means is not shown. An electromagnetic clutch is provided.

When an image signal is input and an image forming operation is started, the drive motor 18 rotates and the electromagnetic clutch is turned on in conjunction with the rotation, and the auxiliary cooling fan 21 rotates to exhibit a cooling effect, and Cooling is continued during the forming operation. When the image forming operation is completed and the operation of each part of the apparatus main body 1 is stopped and the cooling fan 19 and the drive motor 18 are stopped, the electromagnetic clutch is interlocked and turned off.
Thus, the auxiliary cooling fan 21 continues to idle in the same direction due to its own inertial force and continuously exerts a cooling action.

Therefore, after the continuous printing, even if the apparatus main body 1 is stopped in a state where the heat generating portion such as the heat fixing unit 13 stores heat, the cooling operation is still continued by the idling by the inertia force of the auxiliary cooling fan 21. Since the temperature of the heat generating portion that has been exhibited and stored can be effectively lowered, it is possible to ensure the maintenance of components having a low heat-resistant temperature, such as the laser scanner unit 10.

In addition, since an electromagnetic clutch (not shown) serving as drive / non-drive control means is integrally built in the fixed portion of the blade of the auxiliary cooling fan 21, the space can be reduced, and the apparatus can be downsized. I can do it.

Other structures are substantially the same as those of the first and second embodiments, and similar effects can be obtained.

In the case of the present embodiment, as another configuration,
An auxiliary cooling fan 21 is arranged opposite or adjacent to a component that operates most efficiently by maintaining a constant temperature, and a detection unit for detecting the temperature of the component is provided near the component, and detection information of the detection unit is provided. ON / OF of electromagnetic clutch according to
By controlling F, the temperature of the part can be maintained at an appropriate temperature.

[0046]

Since the present invention has the above-described structure and operation, the cooling means driven by the driving means is configured to exhibit the cooling function even after the driving means is stopped. It is possible to prevent an increase in the internal temperature after the device is stopped due to heat storage of the heating element generated therein.

In the case where the cooling means is integrally formed with the one-way transmission means or the drive / non-drive control means for controlling the cooling means so as to exert the cooling action even after the drive means is stopped, Can be reduced in space, and the size of the device can be reduced.

Further, the cooling means is used for cooling the parts having a low heat-resistant temperature, and the parts having a low heat-resistant temperature are provided with a detecting means for detecting the temperature of the parts. In the case where ON / OFF of the drive control means is controlled, the temperature of a component having a low heat-resistant temperature can be maintained at an appropriate temperature.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view illustrating an overall configuration of an image forming apparatus according to the present invention.

FIG. 2 is a perspective view illustrating an arrangement configuration of a cooling unit of the first embodiment of the image forming apparatus according to the present invention.

FIG. 3 is an explanatory plan view showing an arrangement configuration of a cooling unit of the first embodiment.

FIG. 4 is an explanatory side view showing an arrangement configuration of a cooling unit of the first embodiment.

FIG. 5 is an explanatory plan view showing an arrangement configuration of a cooling unit of an image forming apparatus according to a second embodiment of the present invention.

FIG. 6 is an explanatory plan view showing an arrangement configuration of a cooling unit of a third embodiment of the image forming apparatus according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Device main body, 1a ... Structure body, 2 ... Original mounting table, 3 ... Image reading part, 3a ... Contact image sensor, 4 ... Process cartridge, 4a ... Photoconductor drum, 4b ... Primary charger, 4c ... Developing sleeve , 4d: cleaning blade, 4e: drum shutter, 5: front cassette section,
6 MP cassette section, 7 cassette feed section, 8 MP feed section, 9 transfer charger, 10 laser scanner section, 10a
Laser beam oscillator, 10b polygon mirror, 10c folding mirror, 11 control unit, 12 transport guide, 13 heating fixing unit, 14 discharge roller pair, 15 discharge tray, 16 cartridge cover, 17 heat radiation unit , 18 ... drive motor, 18a ...
Drive shaft, 18b output gear, 19 cooling fan, 20 duct, 21 auxiliary cooling fan, 21a drive shaft, 21b gear,
22: gear train, D: manuscript, P: recording sheet

Claims (5)

[Claims] 1. An image forming apparatus for conveying a sheet to form an image, wherein a cooling means driven by a driving means of the image forming apparatus exerts a cooling function even after the driving means is stopped. An image forming apparatus comprising: 2. The image forming apparatus according to claim 1, wherein the cooling unit is a fan that is rotationally driven by the driving unit via a one-way transmission unit. 3. The image forming apparatus according to claim 1, wherein the cooling unit is a fan that is rotationally driven by the driving unit via a driving / non-driving control unit. 4. The cooling means is used for cooling a component having a low heat-resistant temperature, and the component having a low heat-resistant temperature is provided with a detecting means for detecting the temperature of the component, and the drive is performed according to detection information of the detecting means. 4. The image forming apparatus according to claim 3, wherein ON / OFF of the non-drive control unit is controlled. 5. The image forming apparatus according to claim 1, wherein the one-way transmission unit or the drive / non-drive control unit and the cooling unit are integrally formed. apparatus.