JPS62205370A - Image forming device - Google Patents

Abstract

PURPOSE:To simplify the constitution of an image forming device body by providing a temperature detecting means which is able to scan in the image forming device body and detects the temperature at a necessary part and has directivity. CONSTITUTION:The temperature detector 31 provided in the main copying machine consists of a reflecting plate 32 in a horn shape and a temperature sensor 33 provided at the focus position of the reflecting plate 32. The reflecting plate 32 has a directivity range nearly as large as the area of its aperture 34 and heat collected by this reflecting plate 32 is supplied to the temperature sensor 33. Therefore, when copying operation is started and an exposure lamp is moved along an original platen, the temperature detector 31 is rotated correspondingly to detect the temperature of the exposure lamp, whose quantity of exposure is controllable according to the detected temperature information.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to an image forming apparatus applied to, for example, an electronic copying machine.

(Prior Art) As is well known, the exposure lamp used in electronic copying machines is
Generates considerable heat when turned on. Therefore, when a large number of copies are made continuously,
There is a problem in that the temperature of the document table provided opposite to the exposure lamp increases, and depending on the conditions, the document set on the document table may become burnt.

Therefore, the following measures have been taken in the past.

FIG. 3 shows a conventional scanning means.

A reflection plate 42 is provided on the carriage 41, and an exposure lamp 43 is provided inside this reflection plate 42. Further, a temperature fuse 44 is provided on the carriage 41 located on the back side of the reflection plate 42.

In the above configuration, the exposure lamp 43 is turned on to perform exposure scanning of the document, and in this state, the exposure lamp 43
When the temperature of the reflecting plate 42 rises to a predetermined temperature or higher, the temperature fuse 44 is blown and the exposure lamp 43 is turned off, so that the document table etc. are not heated abnormally.

(Problems to be Solved by the Invention) By the way, in the configuration using a temperature fuse for the above purpose,
If the temperature fuse blows out, copying operations cannot be performed, which is inconvenient.

Also, replacing a blown temperature fuse is complicated. Furthermore, temperature fuses are only sensitive to the temperature in the vicinity where they are installed, so if you want to detect the temperature at various locations, you must prepare temperature fuses for each detection location, and the parts As the number of points increases, there are problems such as restrictions on the space in which to install them.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a directional temperature detection means inside the image forming apparatus main body, and the temperature detection means is provided inside the image forming apparatus main body. It has a configuration that allows it to be scanned.

(Function) The present invention is configured to scan the inside of the image forming apparatus and detect the temperature at various locations using a directional temperature detection means provided inside the image forming apparatus. The temperature of various parts of the image forming apparatus can be detected.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 schematically shows an image forming apparatus of the present invention, such as a copying machine. A document table (transparent glass) 2 for supporting a document is fixed to the top surface of the copying machine main body 1. A document cover 11 and a work table 12 are provided near the document table 2.

The document placed on the document table 2 is exposed and scanned by an optical system consisting of an exposure lamp 4 and mirrors 5, 6, and 7 being reciprocated along the lower surface of the document table 2 in the direction of arrow a. It has become so. In this case, mirror 6.7 is moved at half the speed of mirror 5 so as to maintain the optical path length. The light reflected from the original by the scanning of the optical system, that is, the light reflected from the original by the light irradiation of the exposure lamp 4, is reflected by the mirror 5, 6, 7, passes through the variable magnification lens block 8, and is further reflected by the mirror. 9 and guided to the photoreceptor drum 10, so that an image of the document is formed on the surface of the photoreceptor drum 10.

The photosensitive drum 10 is rotated in the direction of arrow C in the figure, and first, the surface thereof is charged by the charging device 11. Thereafter, the image is exposed to slit light to form an electrostatic latent image on the surface. This electrostatic latent image is made visible by applying toner by the developing device 12.

On the other hand, sheets of paper (material to be transferred) P are taken out one by one from the selected upper paper feed cassette 13 or lower paper feed cassette 14 by the delivery rollers 15 or 16, and these taken out papers are passed through the paper guide path. 17
Alternatively, it is guided through 18 to a pair of registration rollers 19, and guided to a transfer section by this pair of registration rollers 19. Here, the paper feed cassette 13.
14 is removably provided at the lower right end of the main body 1, and one can be selected from an operation panel (not shown). In addition, each of the above-mentioned paper feed cassettes 13.
14 are cassette size detection switches 60r,
The cassette size is detected by 602. This cassette size detection switch 601.60
Reference numeral 2 is composed of a plurality of microswitches that are turned on and off in accordance with the insertion of cassettes of different sizes.

The paper P sent to the transfer section is brought into close contact with the surface of the photoreceptor drum 10 at the transfer charger 20, and
The toner image on the photoreceptor drum 10 is transferred by the action of 0. The transferred paper P is electrostatically peeled off from the photoreceptor drum 10 by the action of a peeling charger 21, and then conveyed by a conveyor belt 22 to a fixing roller 23 as a fixing device provided at the end of the conveyor belt 22.
sent to. The transferred image is fixed by passing through this, and the fixed paper P is discharged to a tray 25 outside the main body 1 by a pair of paper discharge rollers 24 . After the photosensitive drum 10 has been transferred, the charge is removed by the charger 26, residual toner on the surface is removed by the cleaner 27, and the residual image is erased by the charge removal lamp 28, so that the drum 10 returns to its initial state. It is supposed to be done. still,
Two cooling fans are used to prevent the temperature inside the main body 1 from rising.

On the other hand, a temperature detector 31 is provided inside the copying machine main body 1. This temperature sensor 31 is shown in FIG.
As shown in (b), a horn-shaped reflector plate 32;
Temperature sensor 3 provided at the focal point of this reflecting plate 32
It is composed of 3. The reflector plate 32 has a directivity range approximately equal to the area of the opening 34 thereof, and the heat collected by the reflector plate 32 is supplied to the temperature sensor 33. Further, the rotation shaft of a pulse motor 35 is fixed to the reflection plate 32 of the temperature detector 31, for example, and the pulse motor 35 causes the temperature detector 3 to
1 is rotated.

In such a configuration, the temperature sensor 31 is connected to the reflector 32.
As shown in FIG. 1, for example, an opening 34 is provided facing toward the document table 2, and the back side of the document table 2 can be scanned. Therefore, when the copying operation is started and the exposure lamp 4 is moved along the document table 2, the temperature of the exposure lamp 4 can be detected by rotating the temperature sensor 31 accordingly. Then, by controlling, for example, the exposure amount of the exposure lamp 4 based on this detected temperature information, it is possible to prevent an abnormal temperature rise in the document table 2 and the like.

According to the above embodiment, the temperature sensor 31 having directivity is provided inside the copying machine main body 1, and by rotating this temperature sensor 31 to scan the inside of the copying machine main body 1, the exposure lamp It is designed to detect the temperature of 4th grade. Therefore, it is possible to detect the temperature at various locations inside the copying machine main body 1 with a small number of parts.

Further, when a conventional temperature fuse blows out, it must be replaced, making maintenance complicated. However, in this embodiment, maintenance is easy because such a need is not required.

Furthermore, since there is no need to provide a conventional temperature fuse on the carriage where the exposure lamp 4 etc. are installed, the configuration of the carriage can be simplified and its weight can be reduced, and the load on the motor that drives the carriage can be reduced. It is possible to do so.

In the above embodiment, the document table 2 is
Although the temperature of the back surface of the device is detected, the temperature is not limited to this, and the temperature of other heat generating portions may be detected.

It goes without saying that various other modifications can be made without departing from the gist of the invention.

[Effects of the Invention] As described in detail above, according to the present invention, a directional temperature detection means is provided inside the image forming apparatus, and the temperature detection means scans the inside of the image forming apparatus to detect various locations. Since the temperature of each part of the image forming apparatus is detected, it is possible to provide an image forming apparatus that has a simpler configuration than the conventional one and can detect the temperature of various parts of the image forming apparatus with a smaller number of parts.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention, and is a side sectional view showing the configuration of an image forming apparatus, FIG. 2 shows a temperature sensor, and FIG. 3(b) is a side sectional view, and FIG. 3 is a perspective view showing a conventional copying machine for explaining a temperature fuse. DESCRIPTION OF SYMBOLS 11... Copying machine main body, 2... Document table, 4... Exposure lamp, 31... Temperature detector, 32... Reflector, 3
3...Temperature sensor, 35...Pulse motor. Applicant's agent Patent attorney Takehiko Suzue (b) (a) Figure 2 Figure 3

Claims (3)

[Claims] (1) An image forming apparatus in which a scanning device optically scans a document set on a document table, and an image forming device transfers an optical image corresponding to the document image onto a transfer material,
An image forming apparatus characterized by comprising a temperature detecting means that is provided to be able to scan the inside of an image forming apparatus main body and has a directivity for detecting the temperature of a desired portion. (2) The image forming apparatus according to claim 1, wherein the temperature detection means includes a reflective member and a temperature sensor provided at a focal point of the reflective member. (3) The image forming apparatus according to claim 1, wherein the temperature detection means is capable of scanning a movement range of the scanning means.