JPH0452165A - Image formation device - Google Patents

Abstract

PURPOSE:To ensure that the opening and the shutting of a door of an additional device is judged without fail with the number of signal wires installed between the additional. device and the main body of the title device minimized by a method wherein the judgement is made to judge whether the door is open or shut in accordance with the level of an output part of a control means while a driving means is turned off with the control means that controls on-off of the driving means. CONSTITUTION:As a power source of a device main body 1 is switched on, output from a control section 17 is cut off. With a multicassette feeder 3a attached to the device main body 1, 24V electricity is supplied from a terminal Pa to a terminal on one end of a solenoid SD through a switch SW, and is further supplied to resistors Ra1, Ra2 through the solenoid SD. Therefore the state of attachment of the multicassette feeder 3a can be judged by the level at a connecting point between the resistors Ra1 and Ra2. As a door provided to the multicassette feeder 3a opens, the switch SW is opened. Then supply of the electricity from the terminal Pa to the resistors Ra1 and Ra2 is cut off and because of this, the level at the connecting point between the resistors Ra1 and Ra2 becomes low. Then the judgement can be made that the door of the multicassette feeder is open.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an image forming apparatus that is detachably attached to the main body of an image forming apparatus and that adds various functions to the main body of the apparatus. The present invention relates to an image forming apparatus having an additional device.

(Prior Art) Conventionally, in an image forming apparatus in which an additional device such as a paper feeder can be attached to the apparatus main body, it is necessary to determine whether or not the additional device is attached when the power is turned on.

FIG. 5 is a block diagram showing a conventional image forming apparatus, in which an auxiliary device 103 is formed to be detachably attached to a main body 101 of the apparatus. The additional device 103 includes a solenoid SD for driving the paper feed roller of this additional device, a door (not shown) that can be opened and closed, and a switch SW that operates in response to the opening and closing of this door. In addition, the device main body 101
It has a control section 105 and a driver circuit 107 that turns on and off the solenoid SD in response to control commands from the control section 105. In addition, the device main body 101
is a terminal PA for supplying power.

PB and PC are provided. Power from terminal PA is applied to solenoid SD. Terminal PB is connected to signal line L2 via resistor R1, and terminal PC is connected to resistor R
2 and is connected to the signal line L3. This signal line L
2. In response to the signal obtained via L3, the additional device 103
determines the installation status of the door and whether the door is opened or closed.

Next, the operation of the conventional example shown in FIG. 5 will be explained with reference to FIG. 6.

When the device main body 101 is powered on in step 5101, the process proceeds to step 8103, where the level of the input A obtained via the signal line L2 is determined. In step 5103, if the level to the input is rHJ level, that is, the terminal P
If the power from B appears directly on the signal line L2,
Proceeding to step 5105, it is determined that the additional device 103 is not attached.

If the input A level or rLJ level is reached in step 5103, that is, if the signal line L2 is connected to the ground via the switch SW, the process proceeds to step 5107, and it is determined that the additional device 107 is attached. . After waiting in step 5109, the process advances to step 5111, where the level of human power B obtained via the signal line L3 is determined. If the input B level is at the "L" level in step 5111, that is, if the switch SW is closed, the process returns to step 5109 and waits. Further, if the level of input B reaches the rHJ level in step 5111, that is, if the switch SW is opened, the process proceeds to step S1]3, and the so-called cover oven is opened in which the door provided in the additional device 103 is in the open state. judge. Next, in step 5115, an operator call is displayed.

(Problem to be Solved by the Invention) However, in the conventional image forming apparatus, in addition to the signal line L1 for driving the solenoid SD, a dedicated signal line is provided for determining the attachment state of the attachment W103 and the open/closed state of the door. L2. L3 is provided, and the main device 101 and additional device 1
The total number of signal lines connecting 03 was increased. For this reason, the number of connection terminals increases, which causes an increase in cost.

Furthermore, since power is supplied from the main device 101 to the additional device 103 via the connection terminal, there is a risk of failure if the connection terminal is incorrectly connected when the additional device 103 is attached.

The present invention has been made in view of the above problems, and aims to reduce the number of signal lines between the main body of the device and the auxiliary device as much as possible to reliably determine whether the door of the auxiliary device is opened or closed, and to reduce costs. The purpose of the present invention is to provide an image forming apparatus that is

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention includes an additional device that is detachably attached to the main body of the device, and a drive section of the additional device that is provided in the additional device. a driving means for driving;
A door provided on the additional device that can be opened and closed; a switching means that operates in accordance with the opening and closing of the door; and when the additional device is attached to the main body of the device, power is supplied to one of the driving means through the switching means. a supply means for supplying to a terminal of the driving means, and an output section connected to the other terminal of the driving means, and controlling the on/off operation of the driving means by setting the impedance of the other terminal to high impedance or low impedance. and determining means for determining whether the door is open or closed according to the level of the output section of the control means when the other terminal of the drive means is set to high impedance by the control means. did.

(Function) According to the present invention, an auxiliary device is detachably attached to the main body of the device, and this auxiliary device includes a drive means, a door that can be opened and closed, and a switching means that operates in accordance with the opening and closing of the door. have.

When the additional device is attached to the apparatus main body, power is supplied to one terminal of the drive means through the switching means, and the on/off operation of the drive means is controlled by the control means on the apparatus main body side.

The output part of this control means is connected to the other terminal of the drive means, and when the control means turns off the operation of the drive means, that is, when the other terminal of the drive means is set to high impedance. The open/closed state of the door is determined according to the level of the output section of the control means. Therefore, the open/closed state of the door can be determined only by the signal line for detecting the level of the output section of the control means. The number of signal lines between the main body of the fruiting device and the additional device can be reduced, and costs can be reduced.

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

First, the overall configuration of the image forming apparatus according to the present invention will be described with reference to FIGS. 2 and 3.

A plurality of additional devices are detachably attached to the main device 1. That is, a multi-cassette feeder 3a is attached to the lower part of the main unit W, an envelope feeder 3b is attached to the back side, and a face-up tray 3c is attached to the front side.

The multi-cassette feeder 3a has a paper feed roller 5 as a driving part and a solenoid as a driving means which will be explained later.
When this solenoid is turned on, the paper feed roller 5 rotates and the paper stored in the multi-cassette feeder 3a is fed. The envelope feeder 3b has a paper feed roller 7 as a drive unit and a solenoid as a drive means. When the solenoid is turned on, the paper feed roller 7 rotates and feeds the paper stored in the envelope feeder 3b. be done. Further, the face-up tray 3c has a conveyance switching gate 9 which is a driving part and a solenoid which is a driving means,
When this solenoid is turned on, the conveyance switching gate 9 operates to discharge the paper to the paper discharge tray 11.

Further, a display section 13 is disposed on the right side of the front surface of the main body 1, and displays various messages, for example, that an additional device is not attached or that a door provided to the additional device is in an open state.

Next, the circuit configuration will be explained with reference to FIG.

A multi-cassette feeder 3a is connected to the apparatus main body 1 via a power line La and a signal line 2.

Further, the envelope feeder 3b is connected to the apparatus main body 1 via a power line tb and a signal line Lb2.

Among the plurality of additional devices, the multi-cassette feeder 3a will be explained as a representative. This multi-cassette feeder 3a has a door (not shown) that can be opened and closed, a switch SW which is a switching means for operating in response to the opening and closing of this door, the above-mentioned paper feed roller 5, and drives the paper feed roller 5. It has a solenoid SD as a driving means. The switch SW opens when the door is opened and closes when the door is closed. Therefore, when the door is closed, power from the power line 11, for example, DC 24V, is supplied to one terminal of the solenoid SD via the closed switch SW. The other terminal of the solenoid SD is connected via a signal line 2 to an output section of a driver circuit 19a, which will be explained later, and the on/off operation of the solenoid SD is controlled by this driver circuit 19a.

The internal structure of the multi-cassette feeder 3a is the same in other additional devices, such as the envelope feeder 3b, and detailed description thereof will be omitted.

Next, the internal configuration of the device main body 1 will be explained. The device main body 1 has a control section 17 and driver circuits 19a and 19b.

The apparatus body 1 also has a supply means for supplying the aforementioned 24 V DC power, and the power from this supply means is supplied to the terminals Pa and Pb. Therefore, when the multi-cassette feeder 3a is installed in the main body 1 of the apparatus, the power from the terminal Pa is supplied to the solenoid SD via the switch SW.
is supplied to one terminal of the

The driver circuit 19a is formed from an open collector type or three-state type element, etc., and is connected to the control section 17, and the output section of the driver circuit 19a is connected to the signal line Lm.
2 to the other terminal of the solenoid SD. Also, a resistor R8 is connected between the signal line Lm2 and the ground.
1 and a resistor Rm2 are connected in series, and a connection point between the resistor R11 and the resistor R02 is connected to the control section 17. Similarly, the driver circuit 19b is formed from an open collector type or three-state type element, and is connected to the control section 17 and to the solenoid via the signal line Lb2. Furthermore, a resistor R5 and a resistor Rb2 are connected in series between the signal line Lb2 and the ground.
The connection point between h and the resistor R12 is connected to the control section 17.

The driver circuits 19a and 19b form a control means, and control the on/off operation of the corresponding solenoids in response to a control signal from the control section 17, for example, a pulse signal with a pulse voltage of 5V.

To be more specific, the driver circuits 19a and 19b are formed from open collector type or three-state type elements as described above, and operate in response to pulse signals from the control section]7 to control the other of the corresponding solenoids. By setting the impedance on the terminal side to high impedance or low impedance, the on/off operation of the corresponding solenoid is controlled.

Further, the control section 17 has a determining means, and determines the level of the output section of the driver circuit 19a, that is, the resistances R11 and R1.
The open/closed state of the door provided in the corresponding auxiliary device is determined according to the signal level at the connection point of the resistors R1 and R12, or the level of the output part of the driver circuit 19b, that is, the signal level of the connection point of the resistors R1 and R12.

Next, the operation will be explained with reference to FIG.

The operation of the multi-cassette feeder 3a among the plurality of additional devices will be described as a representative example.

First, the operation when the multi-cassette feeder 3a is not installed will be explained.

When the device main body 1 is powered on in step S1, the process proceeds to step S3 and the output of the control section 17, that is, the control signal to the driver circuit 19a, is turned off. Next step S5
Now, the level of the output section of the driver circuit 19a, that is, the signal level of the connection point between the resistors R1 and R12 is determined.

Here, when the multi-cassette feeder 3a is not installed, the power line 1 is cut off, so power from the terminal Pa is not supplied to the resistors R, . . . , R12. Further, since the driver circuit 19a formed from an open collector type or three-state type element is off, the output side of the driver circuit 19a is set to high impedance, and no voltage appears at the output section of the driver circuit 19a. Therefore, it is determined in step S5 that the signal level is the rLJ level, and the process proceeds to step S7, where it is determined that the multi-cassette feeder 3a is not loaded.

Next, the operation when the multi-cassette feeder 3a is attached to the apparatus main body 1 will be explained.

When the multi-cassette feeder 3a is attached to the apparatus main body 1, 24V power is supplied from the terminal Pa to one terminal of the solenoid SD via the switch SW. Step S
3, the driver circuit 19a is turned off, so that the impedance of the output side of the driver circuit 19a, that is, the other terminal side of the solenoid SD, is set to high impedance. As a result, the 24V power is supplied to the resistor R*I+Ra7 via the solenoid SD. Here, the resistance ratio between the resistors Rs and R12 is set so that a voltage of 24 V is divided and the divided voltage, that is, the voltage across the resistor R12 is 5. Therefore, in step S5, the resistance R, II
l! : When it is determined that the level of the connection point of R, 2 is the rHJ level, the process proceeds to step S9, and it is determined that the multi-cassette feeder 3a is in the attached state.

Next, step S11 is a so-called standby state in which a printing operation is possible, and after the process is completed at step S11, the process proceeds to step S313. Here, when the door provided on the multi-cassette feeder 3a is opened, the switch SW
opens. Therefore, the supply of power from the terminal Pa to the resistor R@l+ R,2 is cut off. Therefore, in step 313, the level at the connection point between resistors R1 and R12 is set to rLJ.
When it is determined that there is a leveling, the process proceeds to step S15, and it is determined whether the cover oven has the door open. In step 31.7, the operator call is displayed on the display section 13.

Here, when the door provided on the multi-cassette feeder 3a is closed, the switch SW is closed.

As a result, power from terminal Pa is supplied to resistors R, , R, 2 via switch SW and solenoid SD. Therefore, in step 313, if the level at the connection point between resistors R, .

The operation of the multi-cassette feeder 3a described above is similar to that of other additional devices, and detailed explanations thereof will be omitted.

As described above, by reducing the number of signal lines between the auxiliary device and the main body of the device, it is possible to reliably determine the attachment state of the auxiliary device and the open/closed state of the door.

Although the embodiment shown in FIG. 1 shows two types of additional devices, the multi-cassette feeder 3a and the envelope feeder 3b, the present invention is not limited to this, and an appropriate number of three or more types of additional devices can be used. The same can be applied to the case where the device is provided in a detachable manner.

〔Effect of the invention〕

As explained above, according to the present invention, when the control means for controlling the on/off operation of the drive means turns off the drive means, the door of the additional device is opened according to the level of the output section of the control means. Since it is configured to determine whether the door is open or closed, it is possible to reliably determine whether the door is open or closed by minimizing the number of signal lines between the additional device and the main body of the device.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment according to the present invention, FIG. 2 is a perspective view of the embodiment according to the present invention, FIG. 3 is a side view of the embodiment shown in FIG. 2, and FIG. A flowchart showing the operation of the embodiment according to the invention, FIG. 5 is a block diagram of the conventional example,
FIG. 6 is a flowchart showing the operation of the conventional example. ]...Device main body 3a...Multi-cassette feeder 3b...Envelope feeder 3c...Face-up tray 17...Control units 19a, 19b...Driver circuit SW...Switch SD...Solenoid

Claims (1)

[Scope of Claims] An auxiliary device that is detachably attached to the main body of the device, a driving means that is provided within the auxiliary device and drives a drive section of the auxiliary device, and an openable/closeable device that is provided on the auxiliary device. a door, a switching means that operates in response to opening and closing of the door, and a supply means for supplying power to one terminal of the driving means via the switching means when the additional device is attached to the main body of the device. , a control means whose output part is connected to a terminal at the other end of the drive means, and controls the on/off operation of the drive means by setting the impedance of the other terminal to high impedance or low impedance; An image forming apparatus comprising: a determining means for determining whether to open or close the door according to a level of an output section of the controlling means when the other terminal of the driving means is set to high impedance.