JPS63121861A - Original illuminating device - Google Patents

Abstract

PURPOSE:To preclude an electric shock accident due to contact with an exposed high voltage part by fixing one or two adjacent sides of contact glass to a device main body, and arranging a glass detecting means nearby the corner of sides other than the fixed sides and on the side of a flash lamp. CONSTITUTION:The two adjacent sides of the contact glass 3 are fixed to an upper base member by fixing members 6, indications of the sizes of originals and mount positions are printed on the fixing members 6, and a switch 8 is arranged below the free end corner part 14 of the contact glass 3 and on the side of the flash lamp 1, thereby detecting the breakage of the contact glass 3. If the contact glass 3 is broken after electric charging or (and) if a protection cover 11 is opened, a relay 33 is on, so a relay 18 is turned on while the switch 8 or (and) a switch 12 are turned on, thereby generating a warning. Even if a reset signal is generated, the relay 33 is not reset unless a main capacitor 23 is discharged sufficiently. Consequently, an electric shock accident due to contact with the high voltage part which is exposed owing to the breakage of the contact glass.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a Franche lamp type document illumination device, and more particularly to a device that detects breakage of a contact 1 and generates an alarm.
The present invention relates to a document illumination device that displays warnings and stops power supply.

[Prior art]

A flash lamp type document illumination device in an electrophotographic apparatus has a rigger wire provided around the outer periphery of the flash lamp.

By applying a predetermined high voltage to this, the flash lamp is activated to light up. For this reason, if the high-voltage part is exposed due to a breakage of the contact glass, there is a danger of evil spirits, so in order to avoid the danger of evil spirits, the power is automatically cut off when the breakage of the contact glass is detected. there was.

However, even if the power supply to the device is stopped, the main capacitor for the Franche lamp is installed inside the device, and this main capacitor is charged with high voltage, so the contact glass may be damaged. In such cases, there is a risk of electric shock due to contact with high voltage parts within the device.

Therefore, transparent electrodes are coated on the front, back, or inside of the contact glass to detect damage to the contact glass, and an infrared sensor is placed inside the device to detect when an operator inserts his or her hand through a damaged area of the contact glass. When this is detected, the power supply to the charging section is cut off and an alarm is issued.

However, since the transparent electrodes or infrared sensors for safety measures used in the prior art are expensive, there is a drawback that the device itself requires a cost amplifier.

〔the purpose〕

The present invention was made in view of these drawbacks, and
The object is to provide a document illumination device that prevents electric shock accidents caused by contact with high-voltage parts exposed due to broken contact glass without increasing the cost of the device itself.

〔composition〕

To achieve this purpose, one side or two adjacent sides of the contact glass are fixed to the main body of the device, and a switching sensor is arranged near the corner of the fixed side outside the collection and on the Franche lamp side. be.

An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1 and 2 are explanatory diagrams showing the structure of a document illumination device used in an electrophotographic apparatus according to the present invention.

A Franche lamp 1 irradiates light onto the original 4, and a flash lamp 1 is fixed to a lower base member 9 below the flash lamp 1 to prevent light from directly irradiating the original 4 by reflecting light to the original 4 side. A reflector 2 is placed around the flashlamp 1, and a reflector 5 concentric with the flashlamp 1 is arranged to reflect the light irradiated on the opposite side to the reflector 2 toward the reflector 2, thereby increasing lighting efficiency. is increasing.

The contact glass 3 on which the original 4 is placed is fixed to the upper base member 7 by a fixing member 6, and the lower part of the contact glass 3 is adjusted so as to be in constant contact with the lower surface of the contact glass 3, and the upper part A switch 8 fixed to the base member 7 with a bracket (not shown) or the like is provided to constantly detect damage to the contact glass 3.

In addition, for maintenance and inspection inside the flash lamp 1 and other devices, an opening 10 is provided between the upper base member 7 and the lower base member 9 that holds the reflector 2. 11, and an opening/closing detection switch 12 fixed to the lower base member 9 constantly detects the open/closed state of the protective cover 11.Furthermore, there is a main body of the device on the outside of the protective cover 11 and the upper base member 7. An outer cover 13 is provided for protection.

In addition, as shown in FIG. 2, the two sides of the contact glass 3 adjacent to the upper base member 7 are fixed by fixing members 6, and the fixing members 6 are used to indicate the size and placement position of the original 4. printed. The switch 8 is disposed below the free end corner portion 14 of the contact glass 3 and on the flash lamp 1 side, and detects breakage of the contact glass 3.

The Franche lamp 1 is held by a lamp holder 16 and fixed to a lower base member 9. A trigger wire 17, which is a trigger means for causing the Franche lamp 1 to emit light, is wrapped around the flash lamp 1. The trigger wire 17 draws power from both ends of the Franche lamp 1, and connects the trigger unit ( Furthermore, the trigger wire 17 connected to the trigger wire 17 (not shown) is made of nickel wire, and the metal part is exposed.

The protective cover 11 is attached because when the flash lamp 1 is turned on, high pressure is applied to the trigger wire 17, which is very dangerous.

FIG. 3 is an explanatory diagram of the control circuit in the present invention.

A power supply 20 that supplies driving energy inside the device, and a relay 18 (normally closed contact 1) that switches the supply of the power supply 20 from the charging circuit to the warning circuit or vice versa.
9. , 19b and 398° 39), a rectifying and smoothing circuit 21 consisting of a rectifying circuit 50 and a capacitor 51 that removes ripples from the voltage waveform obtained by the rectifying circuit 50, and converting a DC input voltage into an arbitrary DC voltage. A DC-DC converter 22 as a power conversion circuit is provided.

The DC-DC converter 22 includes a resistor 30 that generates a charging detection voltage 1, a main capacitor 24, a flash lamp 1 that is caused to emit light by the main capacitor 24, and a Fransch lamp 1 that is activated by a trigger signal from a control unit 23, which will be described later.
A trigger circuit 25 is connected to eight trigger wires 17 provided around the trigger wire 17.

Further, a coil 52 is installed between the main capacitor 24 and the flash lamp 1 in order to control the discharge time of the flash lamp 1.

Next, a transformer 268 that transforms the power from the power supply 20 as a charging voltage detection circuit, and a rectification and smoothing circuit 2 similar to the above.
7, a three-terminal regulator 283, and a reference voltage V. 29. , 29, a diode 34 for maintaining the charging detection voltage V1 at the peak voltage, and a capacitor 35 are provided.

Also, the reference voltage ■. A comparator 31 for comparing the charge detection voltage V1 with the charge detection voltage V1, a transistor 32 that is turned on by the operation of the comparator 31 and turns on the relay 33, a photocoupler 36 that is turned on in response to a trigger signal from the control section 23, A normally open contact 38 is arranged between a transistor 37 that operates when the photocoupler 36 is turned on, the switches 8 and 12 connected in parallel, and the relay 18 and the switches 8 and 12.

Next, as a warning circuit, a transformer 26 that transforms the power from the relay 18. A rectifying and smoothing circuit 40 similar to the above, a three-terminal regulator 28°, and further connected to the rectifying and smoothing circuit 40 are a buzzer 41 that issues an alarm and an indicator lamp 42 that indicates "danger" and "caution".

In the above configuration, since the switch 8 is disposed below the free end corner of the contact glass 3, when the contact glass 3 is broken, the fragments remain between the fixing member 6 and the upper heath member 7. Even if it is, the switch 8 will surely operate because the fragments at the free end 14 are not held down.

If a piece of contact glass 3 remains with switch 8 pressed down (for example, broken line 15 in FIG. Since it is rare for an operator to insert his/her hand into the cross section and touch the lamp part, it is extremely important from a safety standpoint to place the switch 8 on the free end side 14 of the contact glass 3 as described above. It is valid.

Other operations will be explained using the time chart of FIG.

Normally, switches 8 and 12 are OFF when the contact glass is not damaged and the protective cover is not open.
It is in F status.

Therefore, the relay 18 is also turned off. Normally closed contact 19 of relay 18. , 19b, power is supplied from the electric rX20 to the DC-DC converter 22 via the rectifying and smoothing circuit 21.

During the copy operation, the control unit 23 sends the DC-DC connection 22
The main capacitor 24 is charged by the charging signal for
Thereafter, the trigger circuit 25 is activated by a trigger signal from the control section 23.

Discharge is performed using the trigger wire 17.

Flash lamp 1 emits light.

On the other hand, the transformer 26. Direct current is supplied via 1 and 28 3-terminal regulators. Furthermore, resistance 29. , 29b provides the reference voltage ■. 1 was made again. When the main capacitor 24 is charged, the resistor 30
A charge detection voltage v1 is created by.

The comparator 31 compares the reference voltage V0 and the charging detection voltage (1), and when the charging detection voltage (2) exceeds the reference voltage Vo, the output becomes H4gh, and the transistor 3
2, ONL relay 33 operates.

In this case, the charge detection voltage V is maintained at the peak voltage by the diode 34 and the capacitor 35.

The photocoupler 36 is activated by a trigger signal from the control unit 23.
is ONL, and as a result, the transistor 37 is activated, the capacitor 35 is discharged, and the peak hold is released. Due to this release, the output of the comparator 31 becomes LOW, and as a result, the transistor 32 is turned off and the relay 33 is released.

Therefore, the relay 33 repeats opening and closing operations when the Franche lamp is lit. Further, when the normally open contacts 38 of the relay 33 are both turned off, the relay 18 does not operate even if the normally open contacts 38 are turned on or off.

Next, when the contact glass 1 is damaged or (and) the protective cover is open, a charging signal is generated due to a malfunction or noise to the control unit 23, and the main capacitor 24 is charged, and the charging detection voltage 1
is the reference voltage■. When it becomes higher, relay 33 is activated. At this time, switch 8 or (and) switch 12 is set to O.
Since it is N, the normally open contact 38 of the relay 33 is closed, so the relay 18 is operated.

the result.

Normally closed contact 19 of relay 18. , 19b is released, and the supply of power to the charging circuit is stopped.

On the contrary, the normally closed contacts 39, . 39
．． is closed, and as a result, power is supplied to the transformer 265, and the rectifier smoothing circuit 40 and the three-terminal regulator 28
．． The buzzer 412 and display lamp 42 are turned on via the button 412 to give a warning to the operator and the like.

If the contact glass 1 is damaged or/and the protective cover is opened while the main capacitor 24 is being charged, the normally open contacts 38 of the relay 33 are closed, and the switch 8 or (and) the switch 12 is also closed.
Since it is N, the relay 18 operates in the same way, and as a result, the normally closed contact 19m+1 of the relay 18
9b is released, the supply of power to the charging circuit is stopped.

On the contrary, the normally closed contacts 39-, 39 of the relay 18
b is closed, and as a result, power is supplied to the transformer 265, and the rectifier smoothing circuit 40 and the three-terminal regulator 28
．． The buzzer 411 and display lamp 42 are turned on via the button 411 to give a warning to the operator and the like.

When the buzzer 413 indicator lamp 42 is turned on.

Since the main capacitor 24 self-discharges, the warning can be stopped by outputting a release signal (pulse signal) from the control section 23 after a sufficient period of time has elapsed for the discharge.

Further, in order to ensure reliable operation of the charging voltage detection circuit and the warning circuit so that they will not stop working when the main switch is turned off, it is also good to install a separate power source (for example, a lithium battery).

The part in FIG. 4(I) means the operation of each part in the normal copy mode.

That is, charging is started by a charging signal, and the flash lamp 1 emits and discharges light by a trigger signal. relay 33
is the charging detection voltage V, and is the reference voltage V. O when it gets higher
It is turned off by a trigger signal from the control section 23.

In the part shown in Figure 4 (n), switch 8.12 is set to OFF when not charging.
Even if it is N, the relay 18 does not operate and the warning circuit does not operate. The part shown in FIG. It means the operation of each part at a certain time.

That is, after the start of charging, when the reference voltage is reached, the relays 33 and 18 are turned on. When switch 8 or (and) switch 12 is in an open state, relay 1B is turned off and the warning is canceled, but relay 33 is not turned off and remains in a hold state.

However, since the charging operation is stopped when the relay 18 is turned on, the actual charging detection voltage decreases as the main capacitor 23 naturally discharges, as shown by the two-dot chain line 43. and.

When the charge detection voltage is checked again by the release signal 44 from the control unit 23, the charge detection voltage ■ is equal to the reference voltage V.
. Since it is now lower, the relay 33 will be released at that time.

The part in FIG. 4 (IV) means the operation of each part when the contact glass 3 is damaged or (and) the protective cover 11 is opened after charging.

Since the relay 33 is turned on, the relay 18 is turned on at the same time as the switch 8 or (and) the switch 12 is turned on, and a warning is issued.

Even if the release signal 45 from the control unit 23 is issued, the actual charging detection voltage v1 decreases as shown at 46, so that the reference voltage V. In the above cases, the relay 33 is not released. Therefore, even if the release signal 45 is issued, the relay 33 will not be released unless the main capacitor 23 is sufficiently discharged.2 If the protective cover 11 or the like is opened at this time, the relay 18 will issue an ONL warning.

〔effect〕

As described above, according to the document illumination device according to the present invention, one side or two adjacent sides of the contact glass are fixed to the device main body, and the contact glass is fixed near the corner of the side outside of collection.

In addition, since the switching sensor is disposed on the flash lamp side, it is possible to prevent electric shock accidents caused by contact with the high voltage part exposed due to breakage of the contactor 1 to the glass, without increasing the cost of the device itself.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram of a document illuminating device according to the present invention, FIG. 2 is a partially cutaway perspective explanatory diagram of the document illuminating device according to the present invention, and FIG. 3 is an operating circuit of the document illuminating device according to the present invention. 7 is an explanatory diagram. FIG. 4 is a time chart showing the operation of each part of the document illumination device according to the present invention. Explanation of symbols 1. Flash lamp 3. Contact glass 4. Original 6. Fixing member 7. Dobe heath member 8.12・・
Switch 14... Free end corner part 17... Trigger wire 18... Relay 23...
・Control unit 24 ・・Main capacitor 25 ・・Trigger circuit

Claims (2)

[Claims] (1) Damage to the contact glass on which the document is irradiated by light emitted from a flash lamp that has a trigger wire for activation and is fixed to the main body of the device, and the photoreceptor is exposed by the reflected light, and on which the document is placed. In a document illumination device that detects the contact glass by a glass detection means, cuts off the power supply to the live part, and/or issues an alarm, etc., one side or two adjacent sides of the contact glass are fixed to the main body of the device, and the contact glass is fixed to the device main body. A document illumination device characterized in that the glass detection means is arranged near a corner of a side other than the fixed side and on the side of the flash lamp. (2) The document illumination device according to claim 1, wherein the glass detection means is a switching sensor.