JPH0572646A - Electrostatic copying machine - Google Patents

Abstract

PURPOSE:To reduce required components related to the control of the reciprocating movement of an original placing means by detecting the reciprocating movement amount of the original placing means by detecting the rotational amount of a rotating element. CONSTITUTION:A driving amount detection means which detects the rotational amount of the rotating element which is always rotated when it is energized by a driving source 144 is provided. The driving amount detection means is constituted of an optical detector provided with a light emitting element positioned on one side of the circumferential edge part of a plate to be detected and a light receiving element positioned on the other side. Then, detection signals generated by the various kinds of detection switches and the detector are supplied to a control means 250 being a microprocessor and the actuation of the various kinds of means of a copying machine is controlled by the control means 250 according to the supplied signal as necessary. In other words the rotational amount of the rotating element rotated when it is energized by the driving source 144 is detected and the detected rotational amount of the rotating element is utilized for controlling the reciprocating movement of an original placing means 48.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic copying machine, and more particularly to an electrostatic copying machine having a document placing means which can be reciprocated.

[0002]

2. Description of the Related Art As is well known, an electrostatic copying machine in which an original placing means including a transparent plate on which an original to be copied is placed is reciprocally mounted on an upper surface of a housing is widely put into practical use. Has been done. In such an electrostatic copying machine, usually, the document placing means is drivingly connected to a drive source which may be an electric motor through a transmission mechanism including a forward rotation clutch means and a reverse rotation clutch means. When the document placing means is moved by scanning exposure, the forward rotation clutch means is operated,
When the document placing means is moved back, the reverse rotation clutch means is operated.

[0003]

In a conventional electrostatic copying machine in which the document placing means can be reciprocated, in order to control the reciprocating movement of the document placing means as required, A large number of constituent elements including a large number of detection switches arranged in the reciprocating path are arranged, and the cost required for such constituent elements is not necessarily low.

The present invention has been made in view of the above facts, and its technical problem is to significantly reduce the number of necessary components for controlling the reciprocating movement of the document placing means, as compared with the prior art.
Thus, it is possible to reduce the manufacturing cost.

[0005]

In order to achieve the above-mentioned object, in the present invention, the rotation amount of a rotating element that is rotated when a drive source is energized is detected, and the detection of such rotation amount is performed by a document. It is used to control the reciprocating movement of the mounting means.

That is, according to the present invention, as an electrostatic copying machine that achieves the above-mentioned technical problems, an original placing means having a transparent plate on which an original to be copied is placed and reciprocally mounted. A drive source, a transmission mechanism including a forward rotation clutch means and a reverse rotation clutch means for drivingly connecting the drive source to the document placing means, and rotating when the drive source is energized. A drive amount detecting means for detecting the rotation amount of the rotating element, and a forward rotation clutch means for actuating the document placing means to perform scanning exposure movement from a predetermined scanning exposure start position in a predetermined direction during a copying process. An electrostatic copying machine having control means for actuating the reverse clutch means to move the document placing means in the reverse direction at the same time as or after deactivating the forward clutch means. The control The stage reverses when the rotation amount of the rotating element during the scanning exposure movement of the document placing means and the rotation amount of the rotating element after the document placing means starts the returning movement have a predetermined relationship. There is provided an electrostatic copying machine characterized in that the document latch means is made inoperative so that the document placing means is stopped at a predetermined stop position.

[0007]

In the electrostatic copying machine of the present invention, the forward movement amount and the backward movement amount (thus, the movement amount from the specific position) of the document placing means are detected by detecting the rotation amount of the rotating element, and therefore the document placing device is placed. The manufacturing cost can be reduced by largely omitting the components relating to the position detection of the means.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of an electrostatic copying machine constructed according to the present invention will be described below in more detail with reference to the accompanying drawings.

When the overall construction of the electrostatic copying machine is outlined with reference to FIG. 1, the illustrated electrostatic copying machine has a substantially rectangular parallelepiped housing indicated by numeral 2 as a whole. The housing 2 includes a lower support frame body 4 and an upper support frame body 6, and the upper support frame body 6 is provided between a closed position shown by a solid line in FIG. 1 and an open position shown by a two-dot chain line in FIG. It is rotatably mounted on the lower support frame 4 via a shaft 34. On the upper surface of the housing 2, a document placing means generally designated by numeral 48 is arranged. The document placing means 48 is capable of reciprocating in the left-right direction in FIG. 1 between the scanning exposure start position shown by the two-dot chain line 48A in FIG. 1 and the scanning exposure movement limit position shown by the two-dot chain line 48B in FIG. It is installed. The original document placing means 48 includes a transparent plate 52 on which the original document is placed, and an original document cover (not shown) that covers the transparent plate 52 and the original document placed on the transparent plate 52.

Continuing the description with reference to FIG. 1, a rotary drum 64 having a photosensitive member on its peripheral surface is rotatably mounted at a substantially central portion in the housing 2. Around the rotating drum 64 which is rotated in the direction indicated by the arrow 66, a corona discharger 68 for charging, an optical system 70, an electrostatic latent image developing device 72, and a corona discharger for transfer are sequentially provided when viewed in the rotation direction. 74, a corona discharger for peeling 76, a cleaning device 80 having a cleaning blade 78, and a discharge lamp 8
2 are provided. A document irradiation lamp 84 is provided in association with the optical system 70. The original irradiation lamp 84 passes through the opening 86 formed in the top wall of the upper support frame 6 and passes through the transparent plate 52 of the original placing means 48.
The original document to be copied (not shown) placed on it is illuminated. An optical system 7 configured by arranging in the front-back direction a large number of elongated optical elements extending in the vertical direction (for example, rod-shaped lenses sold by Nippon Sheet Glass Co., Ltd. under the trade name "Selfoc Microlens").
0 projects the reflected light from the document on the peripheral surface of the rotary drum 64 as shown by the arrow in FIG.

A sheet member conveying device generally designated by the numeral 88 is disposed in the substantially lower half portion of the housing 2. At one end of the sheet member conveying device 88, that is, at the right end in FIG. 1, there is provided a copy paper feeding device 90 in the form of a cassette and a sheet member manual feeding device 92 located above it. The copy sheet feeding device 90 includes a copy sheet cassette receiving portion 96 provided with a feed roller 94 and a copy sheet cassette loaded in the copy sheet cassette receiving portion 96 through an opening 98 formed on the right side surface of the housing 2. It is configured to be combined with 100, and by the action of the feeding roller 94, the copying paper is fed one by one from the sheet-shaped copying paper layer 102 contained in the copying paper cassette 100. Manual feeder 92
Is an opening 104 formed in the right side surface of the housing 2.
Through which the guide plate 106 projects outward, a guide plate 108 located above the guide plate 106, and a pair of feed rollers located downstream of these guide plates 106 and 108 (left side in FIG. 1). 110 and 112 are provided. An appropriate sheet member such as sheet copy paper is used as the guide plate 1.
06, which feed roller pairs 110 and 11
When it is advanced to the nip position of 2, the feed roller pair 11
0 and 112 nip the sheet member and feed it. The copy paper fed from the copy paper feeding device 90 between the guide plates 114 and 116, or the sheet member fed from the manual feeding device 92 between the guide plates 114 and 118 is the pair of conveyance rollers 120 and 122. By the action, the rotary drum 64 is passed between the guide plates 124 and 126.
And transfer corona discharger 74 and peeling corona discharger 76
Be transported between. Then, an appropriate conveyor belt mechanism 1
It is conveyed by the action of 28 and sent to the fixing device 130. Then, it is discharged to the tray 134 through the opening 132 formed in the left side surface of the housing 2 (more specifically, the left lower surface wall portion 18 of the lower plate 12). The fusing device 130 includes a fusing roller pair consisting of an upper roller 136 and a lower roller 138 that cooperate with each other (the construction of the fusing device 130 is described in further detail below). The sheet member from the fixing roller pair is discharged to the tray 134 by the action of the discharging roller pairs 140 and 142.

As will be readily understood by referring to FIG. 1, the rotating drum 64, the charging corona discharger 68,
The optical system 70, the developing device 72, the cleaning device 80, the discharge lamp 82, and the original irradiation lamp 84, as well as the guide plate 108 and the feeding roller 11 of the sheet member conveying device 88.
0, guide plate 118, conveyance roller 120, and guide plate 124
Are mounted on the upper support frame 6. On the other hand, the copy paper supply device 90, the guide plate 106, the feeding roller 112, the guide plate 114, the guide plate 116, the conveying roller 122, the guide plate 12
6, transfer corona discharger 74, peeling corona discharger 7
6, transport belt mechanism 128, fixing device 130 and tray 1
34 is attached to the lower support frame 4. Therefore, when the upper support frame 6 is moved from the closed position shown by the solid line to the open position shown by the chain double-dashed line, most of the conveying path of the sheet member is opened, and therefore the sheet member is closed (jam). In this case, the blocked sheet member can be easily taken out.

In the copying machine as described above, while the rotating drum 64 is rotated in the direction indicated by the arrow 66, the charging corona discharger 68 charges the photoconductor to a specific polarity substantially the same and then the optical An image of the original is projected on the photoconductor through the system 70 (in this case, the original placing means 48 moves from the scanning exposure start position shown by the two-dot chain line 48A in FIG.
In the scanning exposure movement to the right), and thus an electrostatic latent image corresponding to the original is formed on the photoconductor. After that,
The developing device 72 applies toner particles to the electrostatic latent image on the photoconductor to develop the electrostatic latent image into a toner image. Then, a sheet member such as a copy sheet fed from the copy sheet feeding device 90 or the sheet member manual feeding device 92 is brought into contact with the photoconductor, and the toner image on the photoconductor is caused by the action of the transfer corona discharger 74. Are transferred onto the sheet member. Then, the sheet member is peeled from the photoconductor by the action of the peeling corona discharger 76. The sheet member on which the toner image is transferred is then conveyed to the fixing device 130, and the fixing device 130
After the toner image is fixed at (3), it is discharged to the tray 134. On the other hand, the rotating drum 64 continues to rotate, the residual toner particles are removed from the photoconductor by the action of the cleaning device 80, and then the residual charge on the photoconductor is erased by the action of the discharge lamp 82.

Next, referring to FIG. 1 together with FIG. 1, a drive system in the copying machine shown in the figure will be summarized. In the illustrated copying machine, the upper support frame 6 is provided with a drive source 144 which may be an electric motor. Then, in association with the drive source 144, the rotary drum transmission mechanism 1
46 and an interlocking transmission mechanism 148 are provided on the upper support frame 6. The transmission mechanism 146 for the rotary drum includes the drive source 1
A toothed pulley 150 fixed to the output shaft of 44, a toothed pulley 152 connected to the rotary drum 64, a tensioning toothed pulley 154 rotatably mounted, and these toothed pulleys 150, 152 and 154. It includes a timing belt 156 wrapped around it. Interlocking transmission mechanism 148
Is a sprocket wheel 158 fixed to the output shaft of the drive source 144, a sprocket wheel 160 rotatably mounted, a sprocket wheel 162 coaxially mounted with the sprocket wheel 160 so as to rotate integrally therewith, and a sprocket. Chain 16 wrapped around wheel 158 and sprocket wheel 160
Includes 4.

The upper support frame 6 is further provided with a transmission mechanism 166 for document placing means and a transmission mechanism 168 for developing device. The document placing means transmission mechanism 166 is mounted on the gear 1 mounted coaxially with the toothed pulley 152 of the rotary drum transmission mechanism 146 so as to rotate integrally therewith.
70, a compound clutch means 176 including a forward rotation clutch means 172 and a reverse rotation clutch means 174, a gear 178, a pinion gear 180, and a rack (not shown) fixed to the document placing means 48. The forward rotation clutch means 172 has an input gear 183 engaged with the gear 170, and the reverse rotation clutch means 174 includes the gear 17.
8 has an output gear 185 engaged with it. The compound clutch means 176 itself including the forward rotation clutch means 172 and the reverse rotation clutch means 174 is a specification of a patent application (title of the invention: electromagnetically controlled spring clutch mechanism) filed on Mar. 23, 1983, which is the application of the present applicant. And the composite electromagnetically controlled spring clutch mechanism disclosed in the drawings, and therefore the description of the structure of the composite clutch means 176 itself is left to the above specification and drawings, and is omitted here. The gear 178 is engaged with the pinion gear 180, and the pinion gear 180 is engaged with the rack extending in the reciprocating direction of the document placing means 48 (that is, the horizontal direction in FIGS. 1 and 2). .. When the forward rotation clutch means 172 of the compound clutch means 176 is actuated while the drive source 144 is energized and the gear 170 is rotated in the direction indicated by arrow 66, the gear 178 and the pinion gear 180 move to the arrow 1 direction.
When the document placing means 48 is rotated at a predetermined speed V in the direction indicated by the arrow 184, and the reverse clutch means 174 of the composite clutch means 176 is actuated, the gear 178 and the gear 178 are rotated. The pinion gear 180 is rotated in the direction indicated by the arrow 186, and thus the document placing means 48 is moved in the direction indicated by the arrow 186 at a speed 2V which is twice the speed V. The developing device transmission mechanism 168 is the interlocking transmission mechanism 148.
18 is mounted coaxially with the sprocket wheels 160 and 162 in FIG.
8, a gear 190 engaged with the gear 188, and a gear 192 engaged with the gear 190. The gear 190 is connected to a sleeve member provided in the developing device 72.

A transmission mechanism 194 relating to the conveyance of the sheet member is mounted on the lower support frame 4. This transmission mechanism 194 includes sprocket wheels 196, 19
8, 200 and 202 and chain 204 wrapped around these sprocket wheels 196, 198, 200 and 202. Sprocket wheel 1
96 is connected to the feeding roller 112 (FIG. 1).
Further, the sprocket wheel 196 is provided with a gear 206 which is coaxial with the sprocket wheel 196 and can be rotated integrally therewith. A gear 208 is engaged with the gear 206, and the gear 208 is supplied to the feeding roller 94 (in the feeding roller 94 of the copy paper feeding device 90 via an appropriate electromagnetically controlled clutch means (not shown). 1). The sprocket wheel 198 is connected to the transport roller 122 via a suitable electromagnetically controlled clutch means (not shown). The sprocket wheel 200 is provided to tension the chain 204. The sprocket wheel 202 is connected to the driven roller 416 (FIG. 1) in the conveyor belt mechanism 128 (FIG. 1). Also, the sprocket wheel 2
The gear 02 is coaxially attached to the gear 02 and is rotated integrally therewith. And this gear 210
The gear 212 is engaged with the gear 212, the gear 214 is engaged with the gear 212, the gear 216 and the gear 218 are engaged with the gear 214, and the gear 220 is engaged with the gear 220. It is engaged. The gear 216 is the upper roller 136 of the fixing device 130.
The gear 220 is connected to the discharge roller 14 (FIG. 1).
It is connected to 2.

As will be easily understood by referring to FIGS. 1 and 2, when the upper support frame 6 is in the closed position, the interlocking transmission provided in the upper support frame 6 is described. Sprocket wheel 16 of mechanism 148
2 is engaged with the chain 204 of the transmission mechanism 194 provided on the lower support frame 4, and thus the drive source 14
4 is drivingly connected to the transmission mechanism 194 via the interlocking transmission mechanism 148. On the other hand, when the upper support frame 6 is moved to the open position shown by the two-dot chain line in FIG. 1, the interlocking transmission mechanism 1
Forty-eight sprocket wheels 162 have a transmission mechanism 194.
It is disengaged from the chain 204.

Next, the operation control of the copying machine as described above will be summarized. Referring to FIG. 1, sheet member detection switches S1 and S2 are arranged in the sheet member conveying path. Detection switch S1
Has a detection arm which crosses the sheet member conveyance path passing between the guide plates 114 and 116 and somewhat upstream of the conveyance roller pair 120 and 122 and the sheet member conveyance path passing through the guide plates 114 and 118. A sheet member fed from the copy paper feeding device 90 and passing between the guide plates 114 and 116 is detected, and a sheet member fed from the manual feeding device 92 and passing between the guide plates 114 and 118 is detected. The detection switch S2 includes the feeding roller pair 11
A detection arm traversing the conveying path of the sheet member inserted through the guide plates 106 and 108, somewhat upstream of 0 and 112, detects a sheet member positioned on the guide plate 106 and manually advanced.

Referring to FIGS. 3 and 4 together with FIG. 1, document placing means detecting switches S3 and S4 are disposed below the document placing means 48. The operation pieces 502, 504 and 50 are provided on the lower surface of the document placing means 48.
6 is fixed. When the document placing means 48 reaches the scanning exposure start position shown by the chain double-dashed line 48A in FIG.
2 acts on the detection switch S3 to close it. When the document placing means 48 is moved by scanning exposure for a predetermined distance from the scanning exposure start position shown by the two-dot chain line 48A in FIG. 1 to the right in FIGS. 1, 3 and 4, the operating piece 504 is moved to the detection switch S4. It acts and closes it. When the document placing means 48 continues the scanning exposure movement to reach the scanning exposure movement limit position shown by the chain double-dashed line 48B in FIG. 1, the operating piece 506 acts on the detection switch S4 to close it (thus, the document placing means). The placing means 48 is reliably prevented from moving beyond the scanning exposure movement limit position shown by the two-dot chain line 48B in FIG. 1 and further moving to the right in FIG. 1).

Further, in the illustrated embodiment, the drive source 1
There is provided drive amount detecting means for detecting the amount of rotation of the rotating element which is always rotated when being biased to 44 (FIG. 2). Explaining with reference to FIGS. 5 and 6, the shaft 508 to which the feeding roller 112 (FIG. 1) is fixed is
The detected plate 510 is also fixed together with the gear 206 already mentioned with reference to FIG. A plurality of notches 512 are formed in the peripheral portion of the detected plate 510 at intervals in the circumferential direction. The drive amount detecting means is composed of an optical detector 518 having a light emitting element 514 located on one side of the peripheral edge of the plate to be detected 510 and a light receiving element 516 located on the other side. Such a detector 518 is
A notch 512 is located between the light emitting element 514 and the light receiving element 516 while the detection plate 510 rotates, and thus, each time the light receiving element 516 receives light from the light emitting element 514 or from the light emitting element 514. A pulse signal is generated every time this light is blocked by the plate to be detected 510.

Referring to FIG. 7, the detection signals generated by the various detection switches and detectors described above are supplied to the control means 250, which may be a microprocessor, and the control means 250 responds to the signals supplied thereto. Control the operation of the various means of the copier as desired. Control means 250
8 shows the control mode of various means of the copying machine according to FIG.
9 and the flow chart of FIG. 9, the copying start switch PS is closed to start the copying process in step n1. Thus, step n
2, the driving source 144 is energized, the peeling corona discharger 76 is energized in step n3, and step n4
In step n5, the static elimination lamp 82 is turned on, and the reverse rotation clutch means 174 of the document placing means transmission mechanism 166 is actuated.
2V from the stop position shown by the solid line to the left in FIG.
The preparations are moved in. In step n6, the first counting means C1 incorporated in the control means 250 subtracts the count value by 2 each time the detector 518 generates a pulse signal (as will be apparent from the description below, the original value is reduced). The first counting means C1 has a predetermined count value at the time when the placing means 48 starts the preparation movement from the stop position).
Next, in step n7, it is determined whether or not the detection switch S3 is closed, and accordingly, whether or not the document placing means 48 has been preliminarily moved to the scanning exposure start position shown by the chain double-dashed line 48A in FIG. When the detection switch S3 is closed, the process proceeds to step n8, in which the reverse rotation clutch means 174 of the document placing means transmission mechanism 166 is made inoperative, and thus the document placing means 48 is shown in FIG. It is stopped at the scanning exposure start position indicated by. In step n9, the first counting means C1 stops the subtraction of the count value (at this point, the count value of the first counting means C1 becomes zero unless an error has accumulated). At step n10, the feeding clutch means CL1 for connecting the feeding roller 94 of the copying paper feeding device 90 to the drive source 144.
Is started, and thus the feeding of the copy paper or sheet member from the copy paper cassette 100 is started. Step n11
In step n12, the document irradiation lamp 84 is turned on, and in step n12, the second counting means C2 incorporated in the control means 250 starts counting the pulse signals generated by the detector 518. In step n13, it is determined whether or not the detection switch S1 is closed, and accordingly, whether or not the leading edge of the sheet member fed from the copy paper cassette 100 has reached the detection arm of the detection switch S1. When the detection switch S1 is closed, the process proceeds to step n14 and the third counting means C built in the control means 250.
3 starts counting the pulse signals generated by the detector 518. Next, in step n15, it is determined whether or not the third counting means C3 has counted a predetermined value. This predetermined value corresponds to the time required from the front edge of the sheet member reaching the detection arm of the detection switch S1 to the nip position of the pair of transport rollers 120 and 122. When the third counting means C3 counts a predetermined value, step n1
6, the feeding clutch means CL1 is made inoperative. Next, in step n17, it is determined whether or not the second counting means C2 that started counting in step n12 has counted a predetermined value. This predetermined value corresponds to the time required for the document irradiation lamp 84 turned on in step n11 to reach a stable state. When the second counting means C2 counts the predetermined value, the process proceeds to step n18 and the charging corona discharger 68 is energized. In step n19, the fourth counting means C4 incorporated in the control means 250 starts counting the pulse signals generated by the detector 518. Then step n
At 20, it is determined whether the fourth counting means C4 has counted a predetermined value. This predetermined value is the same as in step n18 above.
The optical system 70 is moved from a position where a specific position on the photosensitive member is affected by the charging corona discharger 68 by the rotation of the rotary drum 64 during the time required for the charging corona discharger 68 urged in step 2 to reach a stable state. It corresponds to the time added to the time required to move to the position to be exposed via. When the fourth counting means C4 counts the predetermined value, the process proceeds to step n21, and if the count value of the first counting means C1 is not zero due to the accumulated error, it is returned to zero. Step n2
2, the forward rotation clutch means 172 of the document placing means transmission mechanism 166 is operated, and thus the document placing means 48 moves from the scanning exposure start position shown by the two-dot chain line 48A in FIG. 1 to the right in FIG. The scanning exposure movement starts at the speed V. In step n23, the first counting means C
1 starts adding its count value by 1 each time the detector 18 generates a pulse signal. Next, at step n24, it is determined whether or not the detection switch S4 is closed, and accordingly, the document placing means 48 is moved from the scanning exposure start position shown by the two-dot chain line 48A in FIG. 1 to the right in FIG. 1 by a predetermined distance. It is determined whether or not. When the detection switch S4 is closed, the process proceeds to step n25, where the conveyance roller 122 is driven by the drive source 1
The conveyance clutch means CL2 connected to 44 is actuated, and thus the conveyance of the sheet member stopped with the leading edge abutting the nip position of the conveyance roller pair 120 and 122 is started. At step n26, the control means 25
The fifth counting means C5 built in 0 is the detector 51
8 starts counting the pulse signals generated. Next, in step n27, it is determined whether or not the fifth counting means C5 has counted a predetermined value. This predetermined value corresponds to the time required for the leading edge of the sheet member, which has started to be conveyed in step n26, to be conveyed to the position where the transfer corona discharger 74 acts. When the fifth counting means C5 counts the predetermined value, the process proceeds to step n28, and the transfer corona discharger 74 is energized. Then, in step n29, it is determined whether or not the detection switch S1 is opened, that is, whether or not the trailing edge of the sheet member has passed the detection arm of the detection switch S1. When the detection switch S1 is opened, the process proceeds to step n30, and the document placing means transmission mechanism 16
The forward rotation clutch means 172 of No. 6 is deactivated, and thus the scanning exposure movement of the document placing means 48 is finished corresponding to the length of the sheet member. Step n3
At 1, the first counting means C1 stops adding the count values. In step n32, the charging corona discharger 68 is deenergized. In step n33,
Sixth counting means C6 built in the control means 250
Starts counting pulse signals generated by the detector 518, and at step n34, the seventh counting means C7 incorporated in the control means 250 starts counting pulse signals generated by the detector 518. .. Then step n
At 35, it is determined whether the sixth counting means C6 has counted a predetermined value. This predetermined value corresponds to the time required for the trailing edge of the sheet member to pass through the position where it receives the action of the transfer corona discharger 74 after passing the detection arm of the detection switch S1. When the sixth counting means C6 counts the predetermined value, the process proceeds to step n36, in which the transfer corona discharger 74 is deenergized. At step n37, the transport clutch means CL2 is made inoperative.
Next, in step n38, it is determined whether or not the seventh counting means C7 has counted a predetermined value. This predetermined value is
Forward rotation clutch means 1 of the document placing means transmission mechanism 166
After deactivating 72, the reverse rotation clutch means 174
It corresponds to the time interval in which it is desired to be present from the standpoint of preventing vibration, etc., before being activated. When the seventh counting means C7 counts the predetermined value, the process proceeds to step n39,
The document irradiation lamp 84 is turned off. In step n40, the reverse rotation clutch means 174 of the document placing mechanism transmission mechanism 166 is actuated, and thus the document placing unit 48 starts to move back to the left in FIG. 1 at a speed of 2V. Then, in step n41, it is determined whether or not the copying process should be repeated. If the copying process should be repeated, the process returns to step n6. If the copying process should not be repeated, then step n42.
The first counting means C1 starts subtracting the count value by 2 each time the detector 518 generates a pulse signal.
Then, in step n43, the first counting means C1
It is determined whether the count value of is subtracted to a predetermined value.
This predetermined value corresponds to the moving distance between the stop position of the document placing means 48 shown by the solid line in FIG. 1 and the scanning exposure start position shown by the two-dot chain line 48A in FIG. When the count value of the first counting means C1 is subtracted to the predetermined value, the process proceeds to step n44,
Clutch means 1 for reverse rotation of transmission mechanism 166 for document placing means
74 is deactivated. Thus, the document placing means 48 can be stopped at the stop position with sufficient accuracy without requiring a detection switch for detecting that the document placing means 48 has reached the stop position. In step n45, the first counting means C1 stops the subtraction of the count value. In step n46, the eighth counting means C8 incorporated in the control means 250 starts counting the pulse signals generated by the detector 518. Next, in step n47, it is determined whether or not the eighth counting means C8 has counted a predetermined value. This predetermined value may correspond to the time required for the rotary drum 64 to rotate about one more time after the transfer. When the eighth counting means C8 counts the predetermined value, the process proceeds to step n48, where the drive source 144 is deenergized.
In step n49, the peeling corona discharger 76 is deenergized, and in step n50, the static elimination lamp 82 is turned off.

The control mode described above is used in the copy paper feeding device 90.
In the case where the copy sheet, that is, the sheet member is automatically fed from the above, when the sheet member is manually inserted into the manual feeding device 92, the following points are different from the above control mode.
First, instead of determining in step n1 whether or not the copy start switch PS is closed, it is determined whether or not the detection switch S2 is closed, and accordingly, the sheet member is manually inserted and its leading edge is detected. It is determined whether the detection arm of the switch S2 has been reached. Second, step n10,
Step n14, step n15 and step n16 are omitted. Other than that, it is substantially the same as the control mode described above. The feeding roller pairs 110 and 112 of the manual feeding device 92 are brought into contact with the nip positions of the feeding roller pairs 120 and 122 where the leading edges of the sheet members to which they are fed are stopped, and are stopped. However, since the feeding roller 110 is relatively lightly pressed against the feeding roller 112 only by its own weight, for example, the feeding roller 110 continues to rotate without being stopped, and thus the leading edge of the sheet member is stopped. When brought into contact with the nip position of 122 and stopped, the pair of feeding rollers 110 and 112 will slip with respect to the sheet member and will not adversely affect the sheet member.

[0023]

In the electrostatic copying machine of the present invention, the manufacturing cost can be reduced by largely omitting the constituent elements relating to the position detection of the document placing means as compared with the prior art.

[Brief description of drawings]

FIG. 1 is a simplified sectional view showing an embodiment of an electrostatic copying machine constructed according to the present invention.

FIG. 2 is a simplified diagram showing a drive system of the electrostatic copying machine of FIG.

3 is a simplified side view showing a detection switch related to a document placing means in the electrostatic copying machine of FIG.

FIG. 4 is a simplified plan view showing a detection switch related to a document placing means in the electrostatic copying machine of FIG.

5 is a partial cross-sectional view showing components related to drive amount detection means in the electrostatic copying machine of FIG.

FIG. 6 is a partial side view showing components related to drive amount detection means in the electrostatic copying machine of FIG.

7 is a block diagram showing elements related to operation control of the electrostatic copying machine of FIG. 1. FIG.

8 is a part of a flowchart showing an operation control mode of the electrostatic copying machine of FIG.

9 is a part of a flow chart showing an operation control mode of the electrostatic copying machine of FIG.

[Explanation of symbols]

 2: Housing 4: Upper support frame body 6: Lower support frame body 48: Document placing means 52: Transparent plate 64: Rotating drum 68: Corona discharger for charging 70: Optical system 72: Electrostatic latent image developing device 74: Corona discharger for transfer 76: Corona discharger for peeling 80: Cleaning device 84: Original irradiation lamp 88: Sheet member conveying device 90: Copy paper feeding device 92: Sheet member manual feeding device 130: Fixing device 134: Dish 144: Drive Source 146: Transmission mechanism for rotary drum 148: Transmission mechanism for interlocking movement 166: Transmission mechanism for document placing means 168: Transmission mechanism for developing device 172: Clutch means for forward rotation 174: Clutch means for reverse rotation 176: Complex clutch means 250: Control Means 502: Actuating piece 504: Actuating piece 506: Actuating piece 510: Detected plate 512: Notch of detected plate 514: Generated Element 516: light-receiving element 518: Optical detector S1: sheet member detecting switch S2: sheet member detecting switch S3: document bearing means detecting switch S4: document bearing means detecting switch

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazunori Akiyama 1-2-2 Tamatsukuri, Chuo-ku, Osaka Mita Industrial Co., Ltd. (72) Tadashi Umeda 1-2-2 Tamatsukuri, Chuo-ku, Osaka Mita Within Kogyo Co., Ltd. (72) Inventor Keiichi Kishimoto 1-22 Tamatsukuri, Chuo-ku, Osaka Mita Kogyo Co., Ltd.

Claims (7)

[Claims] 1. An original placing means having a transparent plate on which an original to be copied is placed and reciprocally mounted, a drive source, a forward rotation clutch means and a reverse rotation clutch means. A transmission mechanism for drivingly connecting a driving source to the document placing means, a driving amount detecting means for detecting a rotation amount of a rotating element that is rotated when the driving source is energized, and a copying process At this time, the forward rotation clutch means is actuated to move the document placing means in a predetermined direction from the predetermined scanning exposure start position by scanning exposure movement, and then the forward rotation clutch means is deactivated at the same time or thereafter. An electrostatic copying machine including a control means for activating the clutch means for moving the document placing means in the reverse direction and moving the document placing means in the opposite direction; The amount of rotation of the element When the amount of rotation of the rotating element after the document placing means starts the return movement has a predetermined relationship, the reverse rotation clutch means is deactivated and the document placing means is stopped at a predetermined stop position. An electrostatic copying machine characterized by the following. 2. The control means first activates the reverse rotation clutch means to preliminarily move the document placing means in the reverse direction from the stop position during the copying process, and the document placing means. 2. The electrostatic copying machine according to claim 1, wherein said reverse rotation clutch means is made inoperative after the preliminary movement to the scanning exposure start position. 3. The control means deactivates the forward rotation clutch means when the document placing means scans and moves in a predetermined direction from the scan-exposure start position over a distance corresponding to a copy paper length. The electrostatic copying machine according to claim 1 or 2, which is brought into a state. 4. The rotating element is a plate to be detected having a plurality of notches circumferentially spaced at its peripheral edge,
The drive amount detecting means includes a detector having a light emitting element located on one side and a light receiving element located on the other side of the peripheral edge of the plate to be detected, and the notch is provided between the light emitting element and the light receiving element. By being positioned, a pulse signal is generated each time the light-receiving element receives light from the light-emitting element or each time the light from the light-emitting element is blocked by the plate to be detected, and the control means controls the original document. The number of pulse signals generated by the drive amount detecting means during the scanning exposure movement of the placing means and the number of pulse signals generated by the drive amount detecting means after the document placing means starts returning movement are predetermined. The electrostatic copying machine according to any one of claims 1 to 3, wherein, when it comes into a relationship, the reverse rotation clutch means is made inactive. 5. The control means adds each time the drive detecting means generates the pulse signal while the original document placing means moves for scanning and exposure, and while the original document placing means moves for the return movement. 5. The drive detecting means includes counting means for subtracting each time the pulse signal is generated, and when the count value of the counting means is reduced to a predetermined value, the reverse rotation clutch means is deactivated. Electrostatic copier. 6. When the forward rotation clutch means is actuated, the document placing means is moved at a speed V in the predetermined direction,
When the reversing clutch means is actuated, the document placing means is moved in the opposite direction at a speed of 2V, and the counting means is operated while the document placing means is moved in the predetermined direction. 1 every time the drive detection means generates the pulse signal
6. The electrostatic copying machine according to claim 5, wherein each of the document placing means is subtracted by 2 every time the drive detecting means generates the pulse signal while the document placing means is moved in the opposite direction. 7. The electrostatic copying machine according to claim 5, wherein when the document placing means reaches the scanning exposure start position, the counting means is always reset to zero.