JPH043269Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a mounting structure for an interrupter type photo sensor used as various sensors such as paper detection in image forming apparatuses and the like.

[Prior art]

2. Description of the Related Art In recent image forming apparatuses such as copying machines and printers, the main body of the apparatus itself has become smaller, but the number of electrical control units has increased, and the area occupied by the control board containing the control circuit has become larger.

On the other hand, many sensors (sensing devices) are used in the image forming apparatus to detect the presence or absence of paper, the state of paper passage, and the operating states of various movable parts. Among these detection devices, in addition to ordinary microswitches, proximity switches for detecting the movement state of an actuator, photo interrupter type photo switches, and the like are often used. Even in the case of a detection device consisting of a combination of an actuator section and a sensor section, both have conventionally been arranged in a section for detecting the state. For example, both the actuator section and the sensor section of a photo interrupter are placed near the paper feed section or conveyance path, and the output signal from the sensor section is guided to the control board via electric wires to detect the state and respond accordingly. was in control. In this way, the various sensors are arranged in a scattered manner in each part of the device, and the board on which these sensors are mounted is fixedly disposed within the device.

[Problems with conventional technology]

However, in such a conventional structure, the sensor sections that detect the internal state of the image forming apparatus are distributed at various locations within the image forming apparatus, and output signals are controlled from each sensor section via electric wires. When the wires are led to the board, the amount of wiring increases, which hinders the effective use of space within the device, and requires a lot of time for wiring and maintenance work. Additionally, when transmitting output signals via long-distance wiring, especially wiring that runs close to high-voltage power supplies,
There was a problem that noise was easily picked up and false detections occurred. Furthermore, since the control board is fixedly attached, there is a problem in that when a component mounted on the control board breaks down, the replacement work becomes complicated.

[Purpose of invention]

In view of the above-mentioned conventional drawbacks, the present invention reduces the amount of wiring inside the device to effectively utilize space, facilitates wiring work and maintenance work, reduces costs, and facilitates the replacement of malfunctioning parts. The object of the present invention is to provide a mounting structure for a photo sensor that can be used.

[Key points of the idea]

According to the present invention, the above object is achieved by providing a light shielding member interlocked with the actuator in the main body of the device, and
An interrupter-type photo sensor is provided in which a board is removably inserted into the main body, and a slit through which the light shielding member goes in and out is formed in the board. This is achieved by providing a mounting structure for a photo sensor, which is characterized in that the photo sensors are arranged parallel to each other.

[Example of idea]

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 shows the external appearance of the printer according to the present invention.

In the figure, reference numeral 1 denotes a printer main body, and a paper cassette 2 is attached to the side of the main body 1, and this paper cassette 2 is configured to be detachable from the main body 1. Further, an electrical equipment box 3 is provided at the lower part of the main body 1 so as to be insertable and removable in the direction shown in the figure. A control board (not shown) is provided inside the electrical equipment box 3 and has a size that covers almost the entire bottom surface of the box 3. The control board and main body 1 are automatically electrically connected by a connector (not shown) when the electrical equipment box 3 is installed. When a failure occurs in the control board, the electrical equipment box 3 is pulled out to repair or replace the control board.

FIG. 3 shows the internal structure of the printer main body 1 and the main structure of the control board.

The printer main body 1 includes an electrical box 3 and a main body 1.
A base plate 4 is provided to separate the two, and image forming parts including a photosensitive drum 5 are disposed above the base plate 4. Further, an electrical equipment box 3 (not shown in FIG. 3) is attached to the lower part of the base plate 4, and a control board 6 is disposed within this electrical equipment box 3 as described above.

After the photosensitive drum 5 is charged by a charger 7, optical writing is performed by a printing head (not shown). As a result, an electrostatic latent image is formed on the photosensitive drum 5, and this latent image is visualized by the developing device 8 using toner. On the other hand, sheets 9 are stacked in a paper cassette 3 attached to the main body 1, and the uppermost layer of sheets 9 is sent out by rotation of the paper feed roller 10. The top surface of the paper 9 is brought into contact with the tip of an actuator 11 bent into a key shape for detecting that the paper 9 has run out, as will be described later.

The paper 9 is sent out to a standby roll 12, and the standby roll 12 feeds the paper 9 again at the timing when the leading edge of the paper 9 and the leading edge of the toner image formed on the photosensitive drum 5 match. As will be described later, an L-shaped actuator 13 is provided between the standby roll 12 and the paper cassette 3 to detect the passage of the paper 9. The toner image formed on the photosensitive drum 5 is transferred onto a sheet of paper 9 by a transfer device 14, and then conveyed to a fixing device 15. Fuser 1
In step 5, the conveyed paper 9 is fixed by heat fixing, and then the paper 9 is discharged to the outside of the machine by a paper discharge roll 16. Further, an actuator 17 having the same shape as the actuator 13 is disposed between the fixing device 15 and the paper discharge roll 16, and this actuator 17 also has the same shape as the paper 9.
Detects the passage of. Note that after fixing, the photosensitive drum 5
The toner remaining on the surface is removed by a cleaner 18.

Actuator 1 in contact with the top surface of the paper 9
1 can rotate around the shaft 11a, and the shaft 11a
The weight is distributed so that the upper half is heavier than the lower half. Also, the actuator 11
The upper end of a connecting member 19 such as a wire is connected to the connecting member 19, and the light shielding member 20 is connected to the lower end of the connecting member 19. The light shielding member 20 is positioned so as to be located in a slit 21a of an interrupter type photo sensor 21 mounted on the control board 6. Therefore, when the paper 9 in the paper cassette 3 is consumed and the last sheet is gone, the actuator 1
1 rotates counterclockwise in the drawing around the shaft 11a, and the tip of the actuator 11 is connected to the paper loading plate 22.
It protrudes into the hole 22a opened in the hole 22a.
As a result, the light shielding member 20 moves upward from the slit 21a of the photo sensor 21, so that the light emitted from the light emitting part of the photo sensor 21 is received by the light receiving part, and this light reception signal is sent to the control board 6 as a paper out detection signal. The data is sent to the control unit installed in the controller. Note that the connecting member 19 is connected to the actuator 11 and the light shielding member 20 through a hole 4a formed in the base plate 4.

The actuator 13 can rotate about the shaft 13a, and is connected to the light shielding member 24 by the connecting member 23 as described above. An interrupter type photo sensor 25 is mounted on the control board 6.
A light shielding member 24 is located in the slit 25a. Therefore, since the actuator 13 is pushed by the leading edge of the fed paper 9, the actuator 13 rotates counterclockwise around the shaft 13a, and in conjunction with this, the light shielding member 24 is moved upward from the slit 25a. Move to. As a result, the photo sensor 25 enters the light-receiving state as described above, and the light-receiving state is maintained until the rear end of the paper 9 passes the actuator 11. Then, when the rear end of the paper 9 passes the actuator 13, the actuator 13 rotates clockwise and the light shielding member 24 returns to its original position, so that the photo sensor 25 enters the non-light receiving state. A paper passing signal detected by the photo sensor 25 is sent to the control section. In addition, the connecting member 2
3 is connected to the actuator 13 and the light shielding member 24 through a hole 4b formed in the base plate 4.

The actuator 17 has exactly the same structure as the actuator 13 described above, and has a structure that can rotate around a shaft 17a. Further, an interrupter type photo sensor 26 is mounted on the control board 6, and a light shielding member 28 connected to the actuator 17 by a connecting member 27 is connected to the slit 2 of the photo sensor 26.
This is the configuration located at 6a. Actuator 17
is pushed by the leading edge of the paper 9 discharged from the fixing device 15, and rotates counterclockwise around the shaft 17a. In conjunction with this, the light shielding member 28 opens the slit 26.
Since the photo sensor 26 moves upward from a, the photo sensor 26 enters a light receiving state and maintains the light receiving state until the trailing edge of the paper 9 passes. When the trailing edge of paper 9 passes,
The actuator 17 rotates clockwise and the light shielding member 28 returns to its original position in the slit 26a, so that the photo sensor 26 enters the non-light receiving state. The light reception signal from the photo sensor 26 is sent to the control as a paper discharge signal for the paper 9. Further, the base plate 4 is provided with a hole 4c through which the connecting member 27 is inserted.

FIG. 1a shows a state in which the photo sensor 21 is mounted on the control board 6.

The photo sensor 21 is arranged on the control board 6 so that the length direction A of the slit 21a is parallel to the insertion/removal direction B of the control board. Therefore, when inserting or removing the control board 6, since the length direction A of the slit 21a is parallel to the insertion/removal direction B, the light blocking member 20 may be inserted or removed even though it is outside the control board 6. It won't get in the way. Further, the aforementioned photo sensors 25 and 26 are similarly arranged so that the length direction of the slit is parallel to the insertion/removal direction of the control board 6. Note that the same effect can be obtained even if the slit 21a is arranged so that the depth direction C is parallel to the insertion/removal direction B.

In FIG. 1b, instead of the combination of the connecting member 19 and the light shielding member 20, it rotates around an axis 29a,
This shows an example in which a connecting member 29 having a light shielding portion 29b at its tip is used. The light shielding part 29b moves forward and backward in the direction shown in the figure in conjunction with an actuator (not shown), and the photo sensor 21 performs detection accordingly. In the photo sensor 21, the depth direction C of the slit 21a is the insertion/removal direction B of the control board 6.
It is arranged parallel to the Therefore, when inserting and removing the control board 6, since the depth direction C of the slit is parallel to the insertion and removal direction B, the control board 6 can be inserted and removed without the connecting member 29 getting in the way. . In the case of the embodiment shown in FIG. 1b, the slit 21a may also be arranged so that the length direction A of the slit 21a is parallel to the insertion/removal direction B, as described above.

[Effect of idea]

As explained above, according to the present invention, parts such as the actuator are attached to separate parts of the device body, and the photo sensor is mounted on the control board, which reduces the amount of wiring inside the device and makes effective use of space. , wiring work and maintenance work can be made easier and costs can be reduced. Furthermore, there is no need to transmit output signals via long-distance wiring or to run near high-voltage power sources, and it is possible to prevent false detections caused by noise.

Furthermore, since the control board can be inserted into and removed from the main body of the apparatus, if a component mounted on the control board breaks down, it can be easily replaced. In addition, since the photo sensor mounted on the control board is arranged so that the depth direction or length direction of the slit is parallel to the insertion/removal direction of the control board, only the photo sensor can be mounted on the control board, while other Although the light shielding member and the like are arranged in other parts, the control board can be inserted and removed without any trouble.

[Brief explanation of the drawing]

Figures 1a and 1b are perspective views of an embodiment of the present invention;
FIG. 2 is a perspective view of the printer according to the present invention, and FIG. 3 is a configuration diagram showing the internal configuration of the printer. 1...Printer, 3...Electronic box, 4...
Base plate, 6... Control board, 11, 13,
17... Actuator, 21, 25, 26...
Photo sensor, 21a, 25a, 26a...Slit, 19, 23, 27... Connection member, 20, 2
4, 28... Light shielding member.

Claims (1)

[Scope of utility model registration request] A light shielding member interlocked with an actuator is provided in the main body of the device, and a board is provided in the main body in a removable manner, and an interrupter-type photo sensor in which a slit through which the light shielding member enters and exits is formed in the board is inserted in the depth direction of the slit. Alternatively, a photo sensor mounting structure characterized in that the length direction is arranged parallel to the insertion/removal direction of the board.