JPH0677128B2 - Platen movement control device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a document table movement control device such as a copying machine in which a document table is reciprocally provided on the upper surface of a device body.

(Prior Art) Conventionally, in such a platen moving type copying machine, a platen control for preventing the platen from unnecessarily moving and not starting from the proper platen position to perform a copying operation. Devices are known as disclosed in, for example, Japanese Patent Laid-Open Nos. 56-35145 and 58-80664.

However, in the conventional apparatus as disclosed in the above publication, the platen is separated from the drive system at a predetermined point when the platen is returned by the reciprocating motion, and the platen continues to retreat due to its inertia. Since the document table itself is stopped at a predetermined position, it may be difficult to reliably stop the document table at a predetermined position without impacting the latches, etc. due to the large weight of the document table itself. When the document table collides with the latch or the like, the locking mechanism may be damaged. Further, if the document table simply hits the stopper and stops, it may be possible that the document table reacts and moves out of the predetermined position due to the speed at which the document table is returned.

In this way, the document table does not stop at the predetermined stop position, and if there is variation, it is not possible to copy normally during the next copying operation, or the document detection sensor operates in response to opening and closing of the document retainer. A device having a mechanism for detecting the document size has a problem in that the document size cannot be accurately detected.

(Object of the Invention) The present invention addresses the above-mentioned technical problem, and can always stably return the original platen to a predetermined position and stop the original platen. It is an object of the present invention to provide a document table movement control device capable of moving a document table.

(Structure of the Invention) The present invention relates to a document table movement control device which is movably provided on the upper surface of an apparatus main body by a reciprocating drive and control means and fixed to a home position by a lock mechanism, wherein the lock is provided. The mechanism is composed of a lock lever that can be retracted and retracted to engage with and disengage from the platen and restricts its movement, and its driving means. Is provided with means for obtaining a brake timing signal immediately before reaching the home position and means for obtaining a home position signal when the home position is reached, and decelerates the original platen in the backward movement for a minute time based on the brake timing signal. After the lapse of this minute time, the backward movement of the platen is changed to low speed drive, and the lock mechanism is locked based on the home position signal. The driving means is operated so as to be in the locked state.

With this configuration, the document table is always reliably and stably returned to the home position as quickly as possible, and is locked without impact.

(Example) Hereinafter, the Example of this invention is described with drawing.

1 to 3 show the overall structure of a copying machine to which the present invention is applied. The copying machine main body 1 is composed of an upper housing 2 and a lower housing 3, and these upper housing 2 and lower housing 3 are shown. And one end portions of the other are pivotally supported via hinges (not shown) so that they can be opened and closed. A rotatable photosensitive member 4 formed in a drum shape is provided on the upper housing 2 side. A charging device 5, an exposing device 6, a developing device 7, a transferring device 8, a separating device 9 and a cleaning device 10 are arranged around the photoconductor 4. A document table 11 is provided on the upper surface of the upper housing 2 so as to be reciprocally movable by rails 12. Paper feed cassettes 13 and 14 containing copy paper are detachably arranged on one side of the lower housing 3, and a manual paper feed unit 15 for manually feeding paper is provided.
Is provided. From these paper feeding devices to the photoconductor 4
A transfer path 16 for transferring a copy sheet is provided at the transfer portion between the transfer device 8 and the transfer device 8. Further, the transfer path 16 is extended to the other side portion via the separating device 9, and a fixing device 17 is arranged in the middle thereof.
A paper discharge tray 18 is provided at the end.

In the copying machine having such a configuration, the upper casing 2 is rotated upward as shown in FIG. 3 when performing maintenance and inspection of each device in the copying machine main body 1 or when performing jam processing of copying paper. At this time, the document table 11 is prevented from moving in the tilting direction and slipping down by the lock mechanism 27 described later.

On the inner surface of the upper part of the copying machine main body 1 facing the document table 11, detection sensors 19a to 19d and 20a to 2d which are light emitting and light receiving elements for detecting the size of the document placed on the document table 11 are provided.
0d is provided.

FIG. 4 shows the upper surface of the main body of the copying machine. The manuscript table 11 is composed of a manuscript table frame 21, a contact glass 22 fixed to the manuscript table frame 21 on which a manuscript is placed, and both rear ends of the manuscript table frame 21. Document holder 23 that can be opened and closed via hinges 24, 24
FIG. 4 shows a state in which the document holder 23 is opened, and the detection sensors 19a to 19d and 20a to 20d are arranged below the contact glass 22 on the main body 1 side in the lateral direction and in correspondence with a predetermined document size. They are arranged vertically.

FIG. 5 is a view of the document table 11 of the copying machine seen from the side. The document retainer 23 is closed around the hinge portion 24 as a fulcrum, and when it reaches a predetermined angle, it is placed on the contact glass 22. The size of the document D is detected at the operation timing of the opening / closing detection mechanism 39 described later.

FIG. 6 shows the structure of the reciprocating drive means 60 for the document table 11. The reciprocating drive means 60 includes a motor 61 and a wire rope 62 stretched between a pulley provided on the output shaft and the document table 11.

FIG. 7 is an explanatory view of the movement operation of the document table 11 when the main body of the copying machine is viewed from the rear side, and the state of the document table 11 (A) shows when the document table 11 is at the home position, and (B). The state of (1) indicates the time when the original table 11 moves back to the position where the leading edge of the original and the position of the exposure optical system are aligned from the state of (A) and the forward rotation starts, and the state of (C) indicates The state is shown when the document table 11 has moved from the state of (B) to the reverse rotation position where it moves forward and then returns. When the document table 11 is in the state shown in (A), the lock mechanism can be operated to bring it into the locked state.

FIGS. 8 to 12 explain the movement of the document table by the reciprocating drive and control means, which will be described below.

When the document table 11 is located at the home position, a lock mechanism 27 having a retractable lock lever 26 for restricting the movement of the document table 11 is provided on the copying machine main body 1 side, and the lock lever 26 is engaged on the document table 11 side. The receiving parts 25, 25 to be combined are provided. Further, the lock lever 26 is guided by a guide plate 30 and includes a lock release solenoid 31 for releasing the lock by the lock lever 26. That is, the plunger 32 of the solenoid 31 has a spring
33 is inserted and the tip of the plunger 32 is pivotally supported by the intermediate portion of the arm 34 whose one end is pivotally supported, and the other end of the arm 34 is engaged with the protrusion 26a of the lock lever 26. There is.

With this configuration, when the solenoid 31 is off, the extension force of the spring 33 causes the lock lever to move through the arm 34.
When the document table 11 is located at a predetermined home position by pushing up 26, the document table 11 enters the receiving portions 25, 25 to lock the document table 11. On the other hand, when the unlock solenoid 31 is turned on,
The plunger 32 is sucked, and the lock lever 26 is pushed down via the arm 34, thereby releasing the locked state.

On the lower surface of the document table 11, cams 40, 41, and
43 (first row) and cam 42 (second row) are provided,
Micro switches 44a and 44b are provided on the copying machine main body side corresponding to the first and second cam rows, respectively. The position of the document table 11 is detected by a combination of these cams and micro switches, and the detection signal is used as a drive control signal for the solenoid 31 or the motor 61 of the reciprocating drive means 60.

When the document table 11 is located at the home position as shown in FIG. 8, both the switches 44a and 44b are in the ON state by the cams 40 and 42, and the control means described later determines that this state is the home position. It is like this. The time shown in FIG. 8 is the state in which the document table 11 in FIG. 7 is located at (A).

When the copying machine enters the copying operation, the lock release solenoid 31 is turned on to release the lock mechanism 27. Now, as shown in FIG. 8, the document table 11 is at the home position and the lock mechanism 27 is used. In the locked state, it is assumed that the lock lever 26 is pressed against one of the receiving portions 25 and the lock mechanism 27 is constrained by the document table due to its own weight or an unnecessary moving force. Here, in this embodiment, first, the document table 1 is slightly (for example, 100 msec)
1 is rotated in the normal direction, and subsequently the document table 11 is rotated in the reverse direction as shown in FIG. At the above timing, the lock release solenoid 31 pushes down the lock lever 26 to the state shown by the chain double-dashed line in FIG. 9, and the lock is reliably released.

When the document table 11 is reversed and the state shown in FIG. 10 is reached,
The switch 44a is turned off and the switch 44b is turned on to detect that the normal rotation start position is reached. This is the state in which the document table 11 in FIG. 7 is located at (B). From this state, the document table 11 shifts to the normal rotation operation and performs the original copying operation.

Further, the document table 11 is provided with a cam 43 on the first row of the cams 40 and 41 for obtaining the final reverse rotation position signal,
When the cam 43 detects that the switch 44a is at the reverse position of the document table, the document table 11 shifts to the reverse operation. This reverse operation is also performed by the detection signal of the registration switch 69.

Further, when the document table 11 is in the reverse rotation operation, that is, when the document table 11 is in the backward movement operation, and the cam 41 is present before the document table 11 reaches the home position as shown in FIG. From on to off (switch 44b
Is off), and it is determined that it is time to brake the reciprocating drive means 60, and the motor 61 is braked. That is, this cam 41 and the switch 44a constitute a means for obtaining a brake timing signal.

In this state, the manuscript table 11 is further returned at a low speed, and the switches 44a and 44b are both turned on due to the presence of the cams 40 and 42 that reach the home position of the manuscript table 11 as shown in FIG. Emit. Based on this signal, the solenoid 31 is turned off, whereby the lock lever 26 is pushed up by the extension force of the spring 33, and the document table 11 is locked. The cams 40, 42 and the switches 44a, 44b constitute means for obtaining a home position signal when the document table 11 reaches the home position.

In the above, the brake is applied based on the brake timing signal to move the platen 11 back at a low speed. However, instead of this, the platen 11 is once stopped before reaching the home position, and then further moved. You may make it move at low speed until it reaches a home position.

8 to 12, a document retainer opening / closing detection mechanism 39 having a switch 38 for driving the document size detecting means is provided. This is a document retainer 23 provided on the document table 11 so as to be openable / closable. In response to the opening / closing operation of the lock lever 26, the lock lever 26 of the lock mechanism 27 can be slightly pushed down by using a lever or the like provided on a hinge part (not shown) or the like. The switch 38 is operated, and the timing for driving the means for detecting the document size provided on the copying machine main body 1 side is obtained based on the opening / closing detection signal of the document pressing by the operation of the switch 38.

FIG. 13 shows a block diagram of the control means 63 for controlling the operation by the reciprocating drive means 60 as described above.
Is a microcomputer 64, an I / O device 64 'and a home position signal 65, a document table forward rotation start position signal 66, a document table reverse rotation position signal 67, a brake timing position signal 68,
The register switch 69 and other signal input means are provided, and as its output, a document table forward / reverse rotation signal 70, a document table stop drive signal 71, and a clock pulse 72 for determining the document table moving speed are output to the driver 73. This driver 73
Thus, the motor 61 of the reciprocating drive means 60 is driven. Also, the lock release solenoid of the platen
31 drive signals are also output. And the above input signals
65 to 68 are obtained by the cams 40, 41, 42 and 43 and the switches 44a and 44b.

FIG. 14 is a flowchart showing the control operation of the reciprocating drive means 60 and the like by the control means 63 at the start of the copying operation.

In the following, description will be made based on this flowchart. In step S ₁ , the platen lock release solenoid is turned on, and in step S ₂ , it is determined whether or not the platen is at the home position.
Slight time when step S ₃ of, for example, 100msec only to forward the document table. This corresponds to the state shown in FIG. 8 above. Platen in step S ₄ in the case of NO in step S ₂ is examined whether normal rotation start position, if this is YES, the process proceeds to step S _8. If the forward speed of the above step S ₃ and the determination in step S ₄ NO, the reversing document table at step S _5. This corresponds to the state shown in FIG. 9 described above. Thereafter, platen in step S ₆ is checked whether the forward rotation start position and turns on the brake at step S ₇ becomes to YES. This brake electrically controls the motor 61 with a signal 70 by a driver 73.

Then platen start OK whether in step S _8, i.e. a copy sheet is conveyed to the registration roller resist switch
Check if it is ON, and if YES, go to step S
_{At 9} , rotate the platen forward. This corresponds to the state shown in FIG. 10 described above.

Then platen in step S ₁₀ it is checked whether the reverse position, Y
For ES, it reversed the platen moves to step S _12, and if NO checks whether registration switch is turned off in step S _11, it returns to step S ₁₀ to NO, if becomes YES Go to step S ₁₂ . This step
While performing the reverse rotation operation in S ₁₂ , it is checked in step S ₁₃ whether or not the brake timing position is reached. If the result is YES, the brake is turned on for 100 msec in step S ₁₄ . This corresponds to the state shown in FIG. 11 described above.

Then reverse the platen 11 at a low speed in step S _15, namely continued backward movement operation, it is checked whether or not the home position in step S _16, if YES, the stopping platen in step S _17. This corresponds to the state shown in FIG. 12 described above.
And turning off the document table of the lock release solenoid at step S _18, the document table is in the locked state, the operation is terminated.

As described above, when the platen 11 returns, brake the movement of the platen 11 before the platen reaches the home position.
By locking the platen with the lock mechanism when it reaches the home position, the platen 11 can always be stopped at a stable position without impact, and at the stage before reaching the home position. If the document table 11 is once stopped and then moved at a low speed until it reaches the home position, the document table is more stably stopped at the home position, and the lock mechanism is not impacted. Further, in the apparatus having the document size detecting mechanism as in the above embodiment, the document table 11
Is stably stopped at the home position, so that the original size can be accurately detected and a normal copying operation can be obtained.

(Effect of the Invention) As described above, according to the present invention, the reciprocating drive of the document table and the control means cause the document table to return, and the document table is decelerated for a minute time immediately before reaching the home position. At the same time, after the lapse of this minute time, the backward movement of the platen is changed to low speed drive, and the platen is locked by the lock mechanism based on the home position signal, so that the platen is always surely and stable. Can be stopped at the home position, and the reciprocating time is hardly extended, so the reciprocating (copying) time is not unnecessarily extended, the lock mechanism is not impacted at all, and the lock mechanism is damaged. It can be prevented. Further, in the case of having the document size detecting mechanism, the document size can be accurately detected, and a normal copy operation can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a copying machine equipped with a document table lock device of the present invention, FIG. 2 is a sectional view of the copying machine, and FIG. 3 is a state in which an upper casing of the copying machine is rotated. Sectional view at 4th
FIG. 5 is a top view of the original table portion of the copying machine, FIG. 5 is a side view of the original table portion, FIG. 6 is a schematic perspective view of the reciprocating drive means in this apparatus, and FIG. FIGS. 8 to 12 are explanatory views of the movement of the platen and the operation of the lock mechanism, respectively. FIG. 13 is a view of the control means of the reciprocating drive means. A block diagram and FIG. 14 are flowcharts of control by the control means. 1 ... Copier body, 11 ... Document table, 25 ... Reception part, 26 ...
… Lock lever, 27 …… Lock mechanism, 31 …… Unlock solenoid (driving means), 33 …… Spring, 40,42…
… Cam (means for obtaining home position signal), 41 …… Cam (means for obtaining brake timing), 44a, 44b …… Switch, 60 …… Reciprocating drive means, 61 …… Motor, 63 ……
Control means.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Bibliography Sho 54-167733 (JP, U) JP 58-37538 (JP, B2) JP 54-40941 (JP, B2) JP 50- 9010 (JP, Y1)

Claims (2)

[Claims] 1. A document table movement control device movably provided on the upper surface of an apparatus main body by reciprocating drive and control means and fixed to a home position by a lock mechanism, wherein the lock mechanism is a document. It consists of a lock lever that can be retracted and retracted to engage and disengage from the table and its movement, and its reciprocating drive and control means, when the document table is returning, the document table returns to its home position. A means for obtaining a brake timing signal immediately before reaching the home position and a means for obtaining a home position signal when the home position is reached are provided, and the original platen in the backward movement is decelerated for a minute time based on the brake timing signal, and this minute time elapses. Change the backward movement of the rear platen to low speed drive, and lock the lock mechanism based on the home position signal. Yo platen movement control apparatus, characterized in that actuating the driving means. 2. The reciprocating drive and control means temporarily stops the platen before the platen reaches the home position based on the brake timing signal, and moves the platen at a low speed until the platen reaches the home position. The document table movement control device according to claim 1, which is characterized.