JP2528323B2 - Electrostatic copier - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an electrostatic copying machine, and more particularly to an electrostatic copying machine capable of forming an image on both sides of a copy sheet as needed.

<Prior art> From the standpoint of saving copy paper and reducing the number of stored documents,
It is often desired to form an image on both sides of a copy sheet, and therefore, in recent years, an electrostatic copying machine that can form an image on both sides of a copy sheet has been proposed and put into practical use. Has come to be offered to.

A typical example of such an electrostatic copying machine includes a copy paper conveying means that defines a copy paper conveying path, a copy paper supplying means for supplying a sheet copy paper to the copy paper conveying path, and a copy paper discharging path. A specified copy paper discharge means, a copy paper return means that specifies a copy paper return path, a transport switching mechanism for selectively guiding the copy paper to the copy paper discharge path and the copy paper return path, and a copy paper return path A feeding and reversing mechanism for reversing the front and back direction of the copy paper when guiding the copy paper, and for receiving the copy paper returned through the copy paper return path and re-supplying the received copy paper to the copy paper transport path It is equipped with a means for retransmitting copy paper. In such a copying machine, an image is formed on one side of the copy paper while the copy paper supplied from the copy paper supply means to the copy paper carrying path is carried through the copy paper carrying path. When it is desired to form an image only on one side of the copy paper, the copy paper having the image formed on one side is
The transport switching mechanism guides the sheet to the copy sheet discharge path, and the sheet is discharged to the outside of the copying machine through the copy sheet discharge path. On the other hand,
When it is desired to form an image on both sides of a copy sheet, the copy sheet having an image formed on one side is guided to a feed reversing mechanism by a transport switching mechanism, and is copied by the action of the feed reversing mechanism. The front-back direction of the paper is reversed, the paper is introduced from the rear end to the copy paper return path, and is received by the copy paper retransmitting means through the copy paper return path. After that, the copy paper is re-supplied to the copy paper transport path from the copy paper retransmitting means,
An image is formed on the other surface of the copy paper while being re-conveyed through the copy paper conveyance path, and the copy paper on which images are formed on both sides is guided to the copy paper discharge path by the conveyance switching mechanism, and the copy paper discharge path is formed. Is discharged to the outside of the copier through.

However, the conventional electrostatic copying machine described above has the following problems to be solved. That is, in the vicinity of the transport switching mechanism for switching the transport direction of copy paper, the structure for transporting copy paper as required is relatively complicated, and the transported copy paper is also transported in a relatively complex manner. Become. Therefore, paper jam easily occurs in the vicinity of the transport switching mechanism, and when the paper jam occurs, it is difficult to remove the jammed paper relatively easily.

<Object of the Invention> The present invention has been made in view of the above facts, and its main purpose is to easily remove the jammed paper when a paper jam occurs near the transport switching mechanism. It is to provide an electrostatic copier.

<Summary of the Invention> In order to achieve the above object, according to the first invention,
Copy paper conveying means for defining a copy paper conveying path, copy paper supplying means for supplying copy paper to the copy paper conveying path,
A copy paper discharge means that defines a copy paper discharge path, a copy paper return means that defines a copy paper return path, and a copy paper on which an image is formed on one side while being transported through the copy paper transport path. A transport switching mechanism for selectively guiding the copy paper to the discharge path or the copy paper return path; a feed reversing mechanism for reversing the front-back direction of the copy paper when guiding the copy paper to the copy paper return path; Copy paper retransmitting means for receiving the copy paper returned through the copy paper return path and re-supplying the received copy paper to the copy paper transport path, and a copy paper disposed at the downstream end of the copy paper transport path. In an electrostatic copying machine including a fixing device for fixing an image formed on the surface, the transport switching mechanism and the copy paper discharging means are mounted on a supporting frame body mounted on the copying machine main body, and the supporting frame is mounted on the supporting frame body. The body includes the transport switching mechanism and the copy paper discharging means. Is movable between an operating position for locating a fixed position in the main body of the copying machine and a pull-out position for positioning them outside the main body of the copying machine. The fixing device is in a nip state in which they are in pressure contact with each other and mutual pressure contact is released. A fixing roller pair that is selectively biased to the nip released state, holds the fixing roller pair in the nip state when the supporting frame body is in the operating position, and holds the supporting frame body in the operating position. The electrostatic copying machine is provided with an operating mechanism that brings the fixing roller pair into the nip releasing state when the fixing roller pair is positioned at the drawing position.

Further, according to the second aspect of the present invention, a copy sheet conveying unit that defines a copy sheet conveying route, a copy sheet supplying unit that supplies the copy sheet to the copy sheet conveying route, and a copy sheet discharging route are defined. Copy paper discharging means, copy paper returning means for defining a copy paper returning path, and copy paper having an image formed on one side while being conveyed through the copy paper conveying path, the copy paper discharging path or the copy paper returning means. A transport switching mechanism including a pair of guide members that define a transport switching path for selectively guiding the path, a guide holding unit that guides and holds the copy paper guided to the copy paper return path, and a guide holding unit. A feeding and reversing mechanism having a reverse feeding roller for feeding the copied copy paper back and a copy paper returned through the copy paper return path, and the received copy paper is re-supplied to the copy paper transport path. For retransmitting copy paper for In a copying machine, a supporting frame body movably mounted on a copying machine main body between an operating position for positioning the copying machine main body at a predetermined position inside the copying machine main body and a drawing-out position for positioning them outside the copying machine main body, and the supporting frame. An auxiliary frame body is mounted on the body so as to be rotatable between an open position and a closed position, and the supporting frame body is equipped with the transport switching mechanism and the copy paper discharging means, and the auxiliary frame body is mounted on the auxiliary frame body. One of a pair of guide members that define the transport switching path and the reverse feed roller that constitutes a feed reversing mechanism are mounted, and when the auxiliary frame body is set to the open position, the transport switching path and the guide holding are held. There is provided an electrostatic copying machine characterized in that a part of the part is opened.

<Preferred Specific Example of the Invention> A specific example of an electrostatic copying machine constructed according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 schematically shows main components in an embodiment of an electrostatic copying machine constructed according to the present invention. The electrostatic copying machine shown in FIG. 1 includes a housing 2 having a substantially rectangular parallelepiped shape. As will be described in detail later, the housing 2 is defined by a copying machine main body 3 and a support frame body 4 movably mounted on the copying machine main body 3 between an operating position and a drawing position. On the upper surface of the housing 2, a stationary transparent plate 5 on which an original document (not shown) to be copied is placed,
The transparent plate 5 and an openable document pressing member 6 for covering the document placed on the transparent plate 5 are provided.

A rotary drum 8 having an electrostatic photosensitive member on its peripheral surface is rotatably mounted in a substantially central portion of the housing 2. Around the rotary drum 8 which is rotationally driven in the direction indicated by the arrow 10, when viewed in the direction indicated by the arrow 10, the charging area 12 and the exposure area are sequentially arranged.
14, a developing area 16, a transfer area 18 and a cleaning area 20 are provided. The charging area 12 is provided with a charging corona discharger 22, the developing area 16 is provided with a developing device 24, and the transfer area 18 is provided with a transfer corona discharger 26 and a peeling corona discharger 28. The cleaning area 20 is provided with a residual toner removing blade 32.

Above the rotary drum 8, an optical system generally designated by the numeral 34 is arranged. This optical system 34 includes a movable original irradiation lamp 36, a first movable reflecting mirror 38, a second movable reflecting mirror 40, and a third movable reflecting mirror 40.
Movable reflector 42, stationary lens assembly 44 and stationary reflector 46 of
Is included. Movable original illumination lamp for scanning exposure
36 and the first movable reflecting mirror 38 are moved substantially horizontally to the right from the scanning exposure starting position shown in FIG. 1 to the maximum scanning exposure ending position, for example, at the required speed V, and the second movable reflecting mirror 40 is moved. The third movable reflecting mirror 42 is moved substantially horizontally to the right from the scanning exposure start position shown in FIG. 1 to the maximum scanning exposure end position at a speed V / 2 which is half the required speed. At this time, the manuscript placed on the transparent plate 4 is illuminated by the movable manuscript illumination lamp 36, and the reflected light from the manuscript is divided into the first, second and third parts as shown by the one-dot chain line in FIG. Are sequentially reflected by the movable reflecting mirrors 38, 40 and 42 to reach the lens assembly 44, and then are reflected by the stationary reflecting mirror 46 and projected onto the photoconductor in the exposure area 14. When the scanning exposure is completed, the movable original illumination lamp 36 and the first, second and third reflecting mirrors 38, 40 and 42 are returned to the scanning exposure starting position.

At one end of the housing 2, that is, at the right end in FIG. 1, there is provided copy paper feeding means generally designated by numeral 48. The illustrated copy paper feeding means 48 includes a lower cassette receiving portion 50.
a, an intermediate cassette receiving portion 50b and an upper cassette receiving portion 50c are included. The lower cassette receiving portion 50a, the intermediate cassette receiving portion 50b, and the upper cassette receiving portion 50c each have several types of copy paper cassettes that store sheet copy papers of different sizes.
Any one of 52 is selectively and detachably mounted.
Each of the lower cassette receiving portion 50a, the intermediate cassette receiving portion 50b, and the upper cassette receiving portion 50c has a delivery roller for delivering one copy sheet from the copy sheet cassette 52 mounted therein.
54a, 54b and 54c are provided. Lower cassette receiving part 50
The copy paper delivered from the copy paper cassette 52 mounted in a is introduced into the copy paper transport path indicated by numeral 58 as a whole through the copy paper feed path 56a. The copy paper sent from the copy paper cassette 52 mounted on the intermediate cassette receiver 50b is
It is introduced into the copy paper transport path 58 through the copy paper transport paths 56b and 56a. The copy paper sent from the copy paper cassette 52 mounted on the upper cassette receiving portion 50c is transferred to the copy paper feeding path 56.
It is introduced into the copy paper conveyance path 58 through c, 56b and 56a.
The copy paper feed path 56a is defined by the guide plates 62 and 64, the copy paper feed path 56b is defined by the guide plates 66, 68 and 70 and the feed roller pair 72, and the copy paper feed path 56c.
Is defined by guide plates 68, 70, 74 and 76 and a pair of feed rollers 78. The illustrated copy paper supply means 48 further includes a paper feed table mechanism 80. The paper feed table mechanism 80 includes a vertically movable table (not shown), and a delivery roller 82 is arranged above the table. The copy paper sent from the table mechanism 80 is introduced into the copy paper transport path 58 through the copy paper feed path 56d and the copy paper re-supply path (described later). The copy paper feeding path 56d is defined by the guide plates 84 and 86 and the feeding roller pair 88.

The copy paper transport path 58 extends from the upstream end 90 to the downstream end 92 substantially horizontally from right to left in FIG. The copy paper transport path 58 is provided at the downstream portion of the guide plate 64 and the guide plate.
Downstream of 94, a pair of transport rollers 96, a pair of guide plates 98, a pair of transport rollers 100, a guide plate 102, the transfer area 18 (that is, between the rotary drum 8 and the corona discharger 26 for transfer and the corona discharger 28 for peeling). ), The transport belt mechanism 104, the guide plate 106, the heating and fixing roller pair 108, and the guide plate 110, which constitute a copy paper transport means.

A transport switching unit 114 is disposed adjacent to the downstream end 92 of the copy paper transport path 58. Specific example transport switching means 114
Is three rollers arranged vertically, that is, the upper roller.
It includes a transport roller mechanism 118 composed of 115, an intermediate roller 116 and a lower roller 117, and a pair of guide members defining a transport switching path 121, that is, a lower guide member 119 and an upper guide member 120. The upper roller 115, the intermediate roller 116, and the lower roller 117 are rotated in the directions indicated by the arrows, respectively, and the lower guide member 119 and the upper guide member 120 are selectively moved to the lowered position shown by the solid line and the raised position shown by the chain double-dashed line. Positioned. Transport switching means 114
A copy paper discharge path 122 is provided on the downstream side of. The copy paper discharge path 122 is defined by one end of the guide plate 123, the guide plate 124 and the discharge roller pair 125, and these constitute copy paper discharge means. And the other end of the housing 2,
That is, the receiving tray 126 is detachably attached to the left end in FIG.

Further, a feed reversing mechanism 127 and a copy sheet conveying means 128 are provided in association with the conveyance switching means 114. The illustrated feed reversing mechanism 127 includes a guide holding portion that guides and holds the copy paper, and the guide holding portion includes a pair of guide plates 130. The feed reversing mechanism 127 also includes a reverse feeding roller 132 and a pressing roller 134. The reverse feeding roller 132 has a non-acting position shown by a solid line (in the non-acting position, the guide plate 12
3 apart from the other end) and an operating position indicated by a chain double-dashed line (at this operating position, one side of the discharge roller pair 125 (upper side) is passed through an opening (not shown) formed at the other end of the guide plate 123. Acting on the discharge roller)). The pressing roller 134 can be formed of, for example, sponge, and is brought into contact with the other end of the guide plate 123. In the specific example, the path 135 defined by the other end of the guide plate 123, the reverse feed roller 132, the pressing roller 134, and the pair of guide plates 130 is appropriately curved from the upstream end adjacent to the downstream end of the transport switching mechanism 114. It extends in shape. The copy sheet return means 128 includes a return means 136 and a return control means 138, and extends from an upstream end adjacent to the upstream end of the transport switching mechanism 114 to a copy paper return path extending from left to right in FIG. 140 is specified. The illustrated returning means 136 includes a guide plate pair 142, a conveyance roller pair 144, a guide plate pair 146, a conveyance roller pair 148, a guide plate pair 150, a conveyance roller pair 152, and a guide plate pair 154.
Is provided to define the upstream side of the copy paper return path 140, and the illustrated return control mechanism 138 includes a conveyance roller pair 156 and a swing member.
158, a guide plate 160, a conveyance roller pair 162, a swing member 164, a guide plate 166 and a conveyance roller pair 168, and a copy paper return path 140.
Defines the downstream side of the. The rocking members 158 and 164 can rock between a position shown by a solid line in FIG. 1 and a position shown by a chain double-dashed line in FIG. As will be easily understood by referring to FIG. 1, when the lower guide member 119 and the upper guide member 120 of the transport switching mechanism 114 are positioned at the lower position shown by the solid line, the copy paper transport path 58 and the copy paper are transported. Discharge route 122
And are communicated with each other via the transport switching path 121 in the transport switching mechanism 114. On the other hand, when the lower guide member 119 and the upper guide member 120 are positioned at the raised position shown by the chain double-dashed line, the copy paper transport path 58 and the path 135 are mutually moved via the transport switching path 121 in the transport switching mechanism 114. The path 135 and the copy paper return path 140 are communicated with each other via the transport switching path 121 in the transport switching mechanism 114.

In the illustrated electrostatic copying machine, a copy paper retransmitting unit indicated by the numeral 170 is provided below the copy paper returning path 130. The copy sheet retransmitting unit 170 has a receiving table 172. In the specific example, the front part of the pedestal 172 is defined by the upper surface of the receiving block 174, and the rear part thereof is provided on the upper surface of the receiving block 174 at intervals in the width direction (direction perpendicular to the paper surface in FIG. 1). Is defined by the upper edge of the butt strip 176. The rear portion of the pedestal 172 extends with a slight inclination toward the copy paper feeding direction, and the front portion thereof extends substantially horizontally. Stop means 178 is arranged at the front end of the pedestal 172, that is, at the right end in FIG. The stopping means 178 is selectively positioned at either the operating position shown by the solid line or the non-operating position shown by the chain double-dashed line.
A feeding roller 180 is provided above the front end of the pedestal 172. The feeding roller 180 can freely move upward from a position in contact with the upper surface of the pedestal 172 (position indicated by a chain double-dashed line in FIG. 1) to a predetermined position (position indicated by a solid line in FIG. 1). And is forced downward by the biasing action of its own weight (optional spring means if necessary).

Further, there is provided a copy paper re-feeding path indicated by reference numeral 182, which extends from the front end of the copy paper retransmitting means 170 to the upstream end 90 of the copy paper conveying path 58. The copy paper re-supplying means that defines the copy paper re-supply path 182 includes a separation roller pair 184, a guide plate pair 186, a re-supply roller pair 188, and a guide plate pair 19.
0, a re-supply roller pair 192, guide plates 84, 86 and 194, a re-supply roller pair 198 and guide plates 94 and 200.

The operation of the illustrated electrostatic copying machine as described above will be outlined below.

The rotating drum 8 is rotated in the direction indicated by the arrow 10,
In the charging area 12, the surface of the photoconductor on the rotary drum 8 is charged to a specific polarity by the charging corona discharger 26, and in the exposure area 14, the image of the original placed on the transparent plate 4 is converted into the optical system. Scanning exposure is performed on the photoconductor by 34, thus forming an electrostatic latent image on the photoconductor. In development area 16,
The developing device 24 applies toner to the electrostatic latent image on the photoconductor to develop the electrostatic latent image into a toner image. In the transfer area 18, copy paper conveyed through the transfer area 18 (conveyance of copy paper is further referred to later) is brought into contact with the surface of the photoconductor, and the transfer corona discharger 26 acts on the photoconductor. The toner image is transferred onto the copy paper. Then, the copy paper is peeled from the photoconductor by the action of the peeling corona discharger 28. The peeled copy paper is heated by a fixing roller pair 108.
The toner image is fixed on the copy sheet as it is conveyed to the roller pair 108. On the other hand, in the cleaning area 20,
The action of the residual toner blade 32 removes the residual toner from the surface of the photoconductor.

The conveyance of copy paper will be described below.
First, a case of forming an image on only one side of a copy sheet will be described. In this case, the lower guide member 118 and the upper guide member 120 of the transport switching mechanism 114 are positioned at the lowered position shown by the solid line. It is introduced into the copy paper transport path 58 from the copy paper cassette 52 mounted on the lower cassette receiving portion 50a, the intermediate cassette receiving portion 50b or the upper cassette receiving portion 50c, or the table (not shown) of the paper feeding table mechanism 80. Copy paper
It is conveyed through the copy paper conveyance path 58. During this period, the toner image is transferred to one surface (that is, the upper surface) of the copy paper in the transfer area 18, and the toner image is transferred to the heat fixing roller pair 10
The action of 8 fixes it on one side of the copy paper, thus forming an image on one side of the copy paper. The copy paper is then
It is introduced from the copy paper transport path 58 to the transport switch path 121 through the upper roller 115 and the intermediate roller 116 of the transport switch mechanism 114, and is discharged to the tray 126 through the transport switch path 121 and the copy paper discharge path 122. Thus, a copy having an image formed on one side thereof is obtained.

When images are formed on both sides of the copy paper, first, the lower guide member 119 and the upper guide member 120 of the transport switching mechanism 114 are positioned at the raised position shown by the chain double-dashed line. Then, when the copying process is started, the copy paper cassette 52 mounted on the lower cassette receiving portion 50a, the intermediate cassette receiving portion 50b or the upper cassette receiving portion 50c, or the table (not shown) of the paper feeding table mechanism 80. The copy sheet introduced from the copy sheet conveying path 58 is conveyed through the copy sheet conveying path 58. During this time, the toner image is transferred to one surface (that is, the upper surface) of the copy paper in the transfer area 18, and the toner image is fixed on the one surface of the copy paper by the action of the heat fixing roller pair 108, and thus the one surface of the copy paper. An image is formed on. The copy paper from the copy paper transport path 58 is introduced into the transport switching path 121 through the upper roller 115 and the intermediate roller 116 of the transport switching mechanism 114, and passes through the transport switching path 121 to the above-mentioned path 135 of the feed reversing mechanism 127. Proceed to. At this time, the lower surface of the copy paper comes into contact with the one located above the discharge roller pair 125 which is being driven to rotate in a predetermined direction, but a slip is generated between the one discharge roller and the copy paper. And therefore the copy paper is
Even though such a roller is rotationally driven, it can move in a predetermined direction. When the trailing edge of the copy sheet passes through the downstream end of the copy sheet transport path 58, specifically, when it passes through the nip portion of the roller 115 and the intermediate roller 116, the reverse feed roller 132 provided at the upstream end of the path 135 is doubled. The copy paper is pressed against the above-mentioned one roller of the discharge roller pair 125 by the operation position shown by the dotted line. Thus, by the action of the one discharge roller that is being driven to rotate in the predetermined direction, the copy paper is moved forward and backward through the transport switching path 121 and copied between the intermediate roller 116 and the lower roller 117. Introduced into the paper return path 140,
Proceed through the copy paper return path 140. Feed reversing mechanism 127
The reverse feed roller 132 in FIG.
At an appropriate time after being introduced into the vehicle, it is returned to the inoperative position indicated by the solid line.

The copy sheet advanced through the copy sheet returning path 140 is guided to the receiving table 172 of the copying sheet retransmitting means 170, and the receiving table 172 is received.
Go up to the right in FIG. In the specific example, when a relatively long copy sheet is returned through the copy sheet return path 140, the swinging member 158 is switched from the position shown by the solid line in FIG. 1 to the position shown by the chain double-dashed line. Therefore, the relatively long copy paper is guided by the lower surface of the swing member 158 and is received by the receiving projection 176.
Is received in the upper edge, that is, the pedestal 172. Further, when the intermediate length copy sheet is returned through the copy sheet return path 140, the swinging member 164 is switched from the position shown by the solid line in FIG. 1 to the position shown by the chain double-dashed line in FIG. . Therefore,
The copy paper having the intermediate length passes through the upper surface of the swinging member 158 and then is guided to the lower surface of the swinging member 164 to receive the upper edge of the receiving projection 176, that is, the receiving table 172. On the other hand, when a relatively short copy sheet is returned, the swinging members 158 and 164 are held at the positions shown by the solid lines in FIG. Therefore, at this time, the copy paper passes through the upper surfaces of the swing members 158 and 164 and the return roller pair.
It is received in the pedestal 172 by the action of 162 and 168. When the copy sheet is received by the receiving table 172 and fed, the feeding roller 180 acts on the copy sheet to further feed the copy sheet to the right, and thus the leading edge of the copy sheet is indicated by the solid line in the operating position. Is brought into abutment with the stop means 178 located at. As a result, the copying paper is prevented from advancing, and the copying paper is stopped at the required position on the copying paper resending means 170. Even if the feeding roller 180 is rotated at this point, a slip is generated between the feeding roller 180 and the copy sheet, and the copy sheet is not further advanced.

When the required number of copy sheets are returned to the copy sheet retransmitting means 170 as described above, the lower guide member 119 of the transport switching mechanism 114 is provided.
And the upper guide member 120 is returned to the lowered position shown by the actual result.
Then, the stop means 178 in the copy sheet resending means 170 is positioned at the non-acting position indicated by the chain double-dashed line, and the feeding roller 180 which is rotationally driven in the predetermined direction acts to copy the copy sheet from the copy sheet resending means 170. The resupply path 182 is sent out. The copy paper sent to the copy paper re-supply path 182 is advanced through the copy paper re-supply path 182 one by one, and is supplied again to the copy paper transport path 58. As easily understood by referring to FIG. 1, such a copy sheet is turned upside down by passing through a substantially semicircular copy sheet resupply path 182, and one side on which an image has already been formed is placed on the bottom side. In this state, it is supplied to the copy paper conveyance path 58. Next, the copy paper is conveyed through the copy paper conveyance path 58. In this case,
In the transfer area 18, the toner image is transferred to the other surface of the copy paper, that is, the upper surface, and the toner image is fixed on the copy paper by the action of the heat fixing roller pair 108, thus forming an image on the other surface of the copy paper. Next, the copy paper is transferred to the copy paper transport path 58.
From the transfer switching mechanism 114 to the upper roller 115 and the intermediate roller 116
It is introduced to the transfer switching path 121 through the
It is discharged to the tray 126 through the copy paper discharge path 122. Thus, a copy having an image formed on both sides is obtained.

Thus, the above-described configuration and operation of the illustrated electrostatographic copying machine is merely an example of the electrostatographic copying machine to which the present invention can be applied, and therefore a detailed description thereof will be given. It is omitted in this specification.

Next, referring to FIG. 2 together with FIG. 1, a transfer switching mechanism
The structure of 114, the copy sheet discharging unit, and their vicinity will be described. In the electrostatic copying machine of the specific example, the copying machine body 3 includes a front substrate and a rear substrate (both of which are arranged at intervals in the front-back direction (direction perpendicular to the paper surface in FIGS. 1 and 2)). (Not shown), and the above-described various constituent elements (specifically, an area surrounded by a dashed line 202 in FIG. 1) between the front substrate and the rear substrate, except for the transport switching mechanism 114 and the copy paper discharging unit. (Other components except the one located at) are installed. Further, the support frame 4 has a front wall 204 and a rear wall 206 (FIGS. 3 and 4) arranged at intervals in the front-rear direction, and a side wall 208 is provided between the front wall 204 and the rear wall 206. At the same time, a transport switching mechanism 114, copy paper discharging means, etc. are mounted. This support frame 4 is a support mechanism that can expand and contract.
It is attached to the copying machine main body 3 (specifically, a lower support described later) via 210 (for example, a product sold under the trade name Acculide). In the specific example, a pair of support frames 212 and 214 (FIG. 2) mounted slidably on each other.
A support mechanism 210 composed of is provided at an interval in the front-rear direction (only the rear one is shown in FIG. 2), and a support member 212 of one support mechanism 210 is provided on one support wall of a lower support described later. The support member 214 is attached to the front wall 204 of the support frame 4, and the support member 212 of the other support mechanism 210 is attached to the other support wall of the lower support, which will be described later. 214 is attached to the rear wall 206 of the support frame 4. Therefore, the support frame 4 is movably mounted on the copying machine main body 3 between the working position shown by the solid line in FIG. 2 and the drawing position shown by the two-dot chain line in FIG.

In the illustrated specific example, the support frame 4 has an auxiliary frame 216 (secondary frame).
(Fig.) Is installed. The auxiliary frame body 216 includes a front swiveling wall (not shown) and a rear swiveling wall which are arranged at intervals in the front-rear direction.
218, and a front turning wall and a rear turning wall 218 are rotatably attached to the front wall 204 and the rear wall 206 (FIG. 3) of the support frame 4 via the shaft member 220. As shown in FIG. 2, the auxiliary frame body 216 is rotatable between a closed position shown by a solid line and an open position shown by a chain double-dashed line. Is released. If it is not necessary to open the transport switching path 121 and the like, the auxiliary frame body 216 can be omitted, and various components mounted on the auxiliary frame body 216 can be directly mounted on the support frame body 4. Good.

The transport switching mechanism 114 and the like are mounted on the support frame 4 and the auxiliary frame 216 as follows. In a specific example, as shown in FIG. 2, the auxiliary frame body 216 includes an upper roller of the transport switching mechanism 114.
115, an upper guide member 120, a return roller 132 and a pressing roller 134 of the feed reversing mechanism 127 are mounted. Specifically, the upper roller 115, the pressing roller 115, and the pressing roller 134
Is rotatably supported by a front turning wall (not shown) and a rear turning wall 218. Further, the return roller 134 is rotatably supported by the front and rear swivel walls 218 and movably in the direction toward and away from one of the pair of discharge rollers 125 (the shaft portion of the return roller 134 is in the front direction). It is rotatably and movably received in the long holes 222 formed in the turning wall and the rear turning wall 218). In the specific example, an electromagnetic solenoid (not shown) is attached to the return roller 132, and when the electromagnetic solenoid is deenergized, the return roller 132 is in the non-acting position (the position shown in FIGS. 3 and 4). ), But when the electromagnetic solenoid is energized, the return roller 132 is forced to the operating position. Furthermore, a plurality of upper guide portions 120 are arranged at axially spaced intervals on a shaft member 224 that is rotatably supported by the front swivel wall and the rear swivel wall 218, so that the upper guide part 120 rotates integrally with the shaft member 224. Is attached to. In the specific example, the stop members 226 are attached to both ends of the shaft member 224 so as to rotate integrally. In addition, the support frame 4 has an intermediate roller 116, a lower roller 117, and a lower guide member 119 of the transport switching mechanism 114.
Also, the pair of discharge rollers 125 and the guide plate 12 of the copy paper discharging means.
3,124 is installed. Specifically, the intermediate roller 116, the lower roller 117, and the discharge roller pair 125 are rotatably supported by the front wall 204 and the rear wall 206, and the guide plates 123 and 124 are also provided on the front wall 204.
And mounted on the rear wall 206 as required. Further, a plurality of lower guide members 119 are arranged at axially spaced intervals on a shaft member 228 rotatably supported by the front wall 204 and the rear wall 206,
It is mounted so as to rotate integrally with the shaft member 228. The lower guide members 119 located at both ends of the shaft member 228,
Further, a protrusion 230 (only one is shown) is provided corresponding to the pair of stop members 226 (only one is shown). Although not shown, the shaft member 228 is provided with an electromagnetic solenoid. Therefore, when the electromagnetic solenoid is deenergized, the lower guide member 119 is in the position shown in FIGS. 2 to 4, and the stop member 226 abuts the protrusion 230 of the lower guide member 119 to guide the upper guide. Member 120 is shown in solid lines in FIG. 2 and in the positions shown in FIGS. 3 and 4, thus lower guide member 119 and upper guide member 120 are held in the lowered position shown in solid line in FIG. On the other hand, when the electromagnetic solenoid is urged, the lower guide member 119 is moved to the position shown in FIGS.
In the figure, the protrusion 230 is turned clockwise and the protrusion 230 is stopped.
The upper guide member 120 is also swung clockwise in this way, so that the lower guide member 119 and the upper guide member 120 are brought to the raised position shown by the chain double-dashed line in FIG.

In the specific example, the support frame 4 further includes a guide plate pair 142 of the copy paper returning means 128 and a guide plate 110 of the copy paper conveying means.
Further, separation claws 232 and 234 for preventing the copy paper from being wrapped around the fixing roller pair 108 are mounted. In detail, the pair of guide plates 142 and the guide plate 110 are attached to the front wall 204 and the rear wall 206 at required positions. In addition, the separating claw 232 includes a protruding piece (not shown) provided on the front wall 204 and a protruding piece 236 provided on the rear wall 206.
A plurality of support shafts 238 are mounted on the support shafts 238 at intervals in the axial direction of the support shafts 238. Furthermore, the separation claw 234 is
A plurality of support shafts 240 mounted on the front wall 204 and the rear wall 206 are mounted at intervals in the axial direction of the support shafts 240.
As shown in FIGS. 2 and 3, when the support frame 4 is in the above-mentioned operating position, the separation claw 232 and the peripheral surface of the upper fixing roller 242 of the fixing roller pair 108 are brought into contact with or near the separation claw 234.
Touches or contacts the peripheral surface of the lower fixing roller 244 of the pair of fixing rollers.

In the specific example, the nip state of the fixing roller pair 108 is released when the support frame 4 is moved to the pulled-out position. To explain further, in the illustrated example, an intermediate partition (not shown, but disposed in an up-down direction intermediate portion in the housing 2) between the front substrate and the rear substrate (not shown) of the copying machine main body 3. And the lower support 246 of the fixing device is mounted on the upper surface of the intermediate partition. The lower support 246 is a pair of support walls 248 and 250 arranged at intervals in the front-rear direction (the front support wall 248 is shown in FIG. 2, and the rear support wall 250 is shown in FIGS. 3 and 4). Is shown). Support walls 248 and 25
As shown in FIG. 3, on the inner surface of 0, a supporting member 252 is supported by a pin member 254 so as to be swingable in the vertical direction, and is fixed downward in a substantially semicircular concave portion 256 formed in each supporting member 252. roller
A shaft portion 258 of 244 is rotatably supported (in FIGS. 3 and 4, the front side support wall 248 is omitted,
The supporting members 252 and the like are shown only in relation to the front supporting wall 248). The support walls 248 and 250 have pins 260
Upper walls 262 and 264 are mounted via (showing both pins mounted on support wall 248 in FIG. 2 and one pin mounted on support wall 250 in FIGS. 3 and 4) (In FIG. 2, the front upper wall 262 is shown,
The upper wall 264 on the rear side is shown in FIGS. Both ends of the upper fixing roller 242 are rotatably supported by the upper walls 262 and 264, and a heater 266 is provided inside the hollow upper fixing roller 242.
Such heating means is provided. Therefore, as understood from FIGS. 3 and 4, when the support member 252 is positioned at the first angular position shown in FIG. 3, the lower fixing roller 244 moves upward in the vicinity of the upper fixing roller 242, Thus, the upper fixing roller 242 and the lower fixing roller 244 are held in the nip state. On the other hand, when the support member 252 is moved to the second angular position shown in FIG.
Move downwards and away from the top fixing roller 24
2 and the lower fixing roller 244 are held in the nip released state.

In the specific example, an operating mechanism 268 for swinging the support member 252 in association with the movement of the support frame 4 is further provided. Incidentally, in the specific example, an actuating mechanism 268 having substantially the same configuration is provided corresponding to each of the support members 252, and in the following description, the one provided in relation to the front support member 252 will be described. . Mainly referring to FIG.
The illustrated actuation mechanism 268 includes an intermediate lever 270, a swiveling member 272, and an action pin 274. The intermediate lever 270 has a substantially L-shape, and its substantially central portion is rotatably mounted on the inner surface of the support wall 248 via a pin 276. A pin 278 protruding inward is fixed to one end of the intermediate lever 270,
The pin 278 acts on the contact portion 280 provided on the support member 252. The turning member 272 is also attached to the inner surface of the support wall 248 via a pin 282 so as to be freely turnable. An L-shaped bracket 284 is rotatably attached to one end of the swivel member 272 (the side where the pin 282 is present) via a pin 285 (Figs. 3 and 4). A shaft member 288 to which a nut 286 is screwed is inserted through a hole formed in the bracket 284, and a coil spring 289 that constitutes elastic means is interposed between the shaft member 288 and the other end of the intermediate lever 270. That is, one end of the coil spring 289 is locked to the shaft member 288 and the other end is locked to the other end of the intermediate lever 270. A cam groove 290 is formed at the other end of the turning member 272 so as to curve and extend toward the one end. On the other hand, the action pin 274 is provided on the outer surface of the front wall 204 of the support frame body 4. The action pin 274 is removably received in the cam groove 290 of the turning member 272. Although not shown, the intermediate lever 270 and the turning member 272 of the other actuating mechanism 268 are mounted on the inner surface of the other supporting wall 250 (FIGS. 3 and 4) as required, and the action pin 274 is also provided. Is provided on the outer surface of the rear wall 206 of the support frame 4. With such a configuration, when the support frame 4 is moved in the direction indicated by the arrow 292 (FIGS. 2 and 4) toward the working position, the working pin 274 causes the turning member 2 to move.
The turning member 272 is received in the cam groove 290 of the 72, and the turning member 272 moves in accordance with the movement of the support frame 4 in the direction shown by the arrow 292 (see FIG. 3).
It turns in the direction shown by. On the other hand, when the support frame 4 is moved from the operating position in the direction indicated by the arrow 296 (FIGS. 2 and 4) toward the pull-out position, the action of the action pin 274 is accompanied by the movement of the supporting frame 4. The turning member 272 has an arrow
It is turned in the direction indicated by 298 (Fig. 3).

In the illustrated specific example, lock means 300 for releasably holding the support frame 4 in the above-mentioned operating position is provided. Referring to FIG. 2 again, the illustrated locking means 300 has the operating member 3
02, the engaging member 304 and the engaging pin 306 are provided. The operation member 302 is mounted on the copying machine main body 3 so as to be movable in the left-right direction in FIG. An operation portion 302a is provided at one end of the operation member 302, and the operation portion 302a is provided on the side wall 208 of the support frame body 4 when the support frame body 4 is in the operating position.
It is exposed to the outside through an opening 308 formed in the. A connecting pin 310 is provided at the other end of the operating member 302. The illustrated engaging member 304 is substantially L-shaped, and its substantially central portion is rotatably mounted on the support wall 248 via a shaft 312. A recess 314 is provided at one end of the engaging member 304,
The connecting pin 310 is received in the recess 314. A claw 316 that can engage with the engagement pin 306 is provided at the other end. On the other hand, the engagement pin 306 is provided on the support frame 4,
Specifically, it is provided on the front surface of the front wall 204. Therefore, when the support frame 4 is moved in the direction indicated by the arrow 292 to the above-mentioned operating position, the engagement pin 306 causes the claw 316 of the engagement member 304 to move.
And then engages with the pawl 316 over the inclined portion of the. On the other hand, the operating member 3
When the operating portion 302a of 02 is pressed and moved in the direction indicated by the arrow 318 (FIG. 2), the engaging member 304 is swung in the direction indicated by the arrow 320 (FIG. 2) by the action of the connecting pin 310, thus The engagement between the claw 316 of the engaging member 304 and the engaging pin 306 is released. It is preferable to provide a biasing means (not shown) such as a screw coil spring that biases the engaging member 304 in the counterclockwise direction in FIG. 2, that is, in the direction opposite to the direction indicated by the arrow 320.

In the specific example, a positioning means for surely positioning the support frame 4 at the working position is also provided. The illustrated positioning means is composed of a pair of positioning pins 322 (only one of which is shown in FIG. 2) and a combination of positioning holes (not shown) provided corresponding to the pair of positioning pins 322. In the illustrated specific example, a pair of positioning pins 322 are provided on the lower connecting wall 324 that connects the front wall 204 and the rear wall 206 of the support frame body 4 at intervals in the front-rear direction. In addition, a pair of positioning holes are formed in the hanging wall 326 provided on the lower support 246 of the fixing device at intervals in the front-rear direction. When the support frame 4 is moved toward the working position, the pair of positioning pins 322 are detachably received in the positioning holes in the vicinity of the working position,
Positioning of the support frame 4 in the working position is thus achieved.

Next, with reference to FIGS. 2, 3, and 4, the operation and effect of the above electrostatic copying machine will be described.

When the support frame 4 is pulled out, the lock by the lock means 300 may be released and the support frame 4 may be moved in the direction indicated by the arrow 296. That is, the operation portion 302a of the operation member 302 is pressed to move the arrow 3
Move in the direction indicated by 18. Thus, the engaging member 304
Is swung in the direction indicated by the arrow 320, and the claw 316 of the engaging member 304 is rotated.
And the engaging pin 306 are disengaged, and thus the support frame 4
The movement in the direction indicated by the arrow 296 is allowed. After that, the support frame 4 is moved toward the drawn-out position in the direction indicated by the arrow 296. By doing so, the positioning pin 322 provided in the support frame 4 is disengaged from the positioning hole (not shown) formed in the lower support 246 by such movement. Also,
Along with such movement, the action pin 27 provided on the support frame 4
4 acts on the swivel member 272 to swivel the swivel member 272 in the direction indicated by the arrow 298 (FIG. 3), and then separates from the cam groove 290 formed in the swivel member 272. As shown in FIG. 4, when the turning member 272 is turned, the bracket 284 attached to the turning member 272 is moved in the direction approaching the intermediate lever 270.
On the other hand, at this time, the lower fixing roller 244 acts on the supporting member 252. Therefore, when the bracket 284 is moved so far, the supporting member 252 is moved downward by the weight of the lower fixing roller 244 (that is, in the direction away from the upper fixing roller 242), and the intermediate lever 270 is moved through the supporting member 252 in FIG. Is rotated counterclockwise, and thus moves downward to the lower fixing roller 244 so as to be separated from the upper fixing roller 242, and the lower fixing roller 244 releases the nip state of the upper fixing roller 242.
Incidentally, it is preferable to provide, in association with the support member 252, a blocking piece (not shown) for blocking the support member 252 from further rotating counterclockwise from the position shown in FIG.

When the support frame 4 is moved to the pull-out position shown by the chain double-dashed line in FIG. 2, various components mounted on the support frame 4 are positioned outside the copying machine main body 3.
In the specific example, when the support frame 4 is pushed to the pull-out position, the support mechanism 210 is extended most, and the extension of the support mechanism 210 is blocked, so that the movement of the support frame 4 beyond the pull-out position is blocked. It When it is set to the above-mentioned withdrawal position, as can be understood from FIG. 2, the copy paper discharging means and the transport switching mechanism 114 mounted on the support frame 4 are positioned outside the copying machine main body 3 and further the feeding reversing mechanism 127. A part (specifically, the guide plate 123, the reverse feed roller 132 and the pressing roller 134) and a part of the copy sheet returning means 128 (specifically, the guide plate pair 142) are also positioned outside the copying machine main body 3. Therefore, when the copy paper is jammed at the transport switching path 120 and the copy paper discharge path 122, and further at one end of the path 135 and the upstream end of the copy paper return path 140, the support frame 4 is moved to the pull-out position. By positioning, the jammed paper can be easily removed. Further, in the specific example, the nip state between the upper fixing roller 242 and the lower fixing roller 244 of the fixing device can be released by moving the support frame 4 to the pull-out position, and therefore, the paper jam occurs in the fixing device. Even in this case, the jammed paper can be easily removed through the space created between the copying machine body 3 and the support frame 4.

In the specific example, the auxiliary frame body 216 is openably and closably mounted on the support frame body 4. Therefore, the auxiliary frame body 216 can be moved to the open position as shown by the two-dot chain line in FIG. Thus, the upper roller 115 and the intermediate roller 116 of the transport roller mechanism 118 are
The nip state between them is released. Further, the upper guide member 120 is moved upward with respect to the lower guide member 119, and the transport switching path 1
21 is also open. Further, the reverse feeding roller 132 and the pressing roller 1
34 is also moved in a direction away from the other end of the guide plate 123, and a part of the guide holding part 127, that is, one end of the path 135 is also opened. Therefore, when a paper jam occurs at one end of the transport roller mechanism 118, the transport switching path 121, and the path 135, the auxiliary frame body 216 is moved to the open position to easily remove the jammed paper. You can

On the other hand, by turning the auxiliary frame body 216 counterclockwise in FIG. 2, it is shown by a solid line in FIG.
(Also shown in Fig. 4 and Fig. 4).
In the specific example, the pressing roller 134 comes into contact with the other end of the guide plate 123 to prevent the auxiliary frame body 216 from pivoting beyond the closed position. In this closed position,
The various mechanical elements mounted on the support frame 4 and the various structural elements mounted on the auxiliary frame 216 are held in the positional relationship shown by the solid line in FIG.

Thereafter, by moving the support frame 4 in the direction indicated by the arrow 292, the support frame 4 can be moved to the operating position shown by the solid line in FIG. 2 and shown in FIG. When the support frame body 4 is moved in the direction indicated by the arrow 292, the positioning pin 322 provided in the support frame body 4 is received in the positioning hole (not shown) formed in the lower support frame body 246, and thus the support frame body is formed. The body 4 is positively positioned in the working position. In addition, when moved so, the support frame 4
The action pin 274 provided at the position is located in the cam groove 290 of the swiveling member 272 and swivels it in the direction shown by the arrow 294 (FIG. 3). As a result, the bracket 284 is moved to the left in FIG. 3, and the intermediate lever 270 is pivoted clockwise in FIG. 3 via the shaft member 288 and the coil spring 290. When pivoted this way, further support member 252 is passed through pin 278.
Is rotated upward, that is, in the direction of approaching the upper fixing roller 242. Then, when the support frame 4 is moved to the working position, as shown in FIG. 3, the lower fixing roller 244 is moved upward and the upper fixing roller 242 and the lower fixing roller 244 are kept in the nip state. The nip pressure at this time can be adjusted by changing the position of the nut 286. Further, when it is moved to the working position, the engaging pin 30 provided on the support frame 4 is shown by the solid line in FIG.
6 and the claw 316 of the engaging member 304 on the copying machine main body 3 side are engaged with each other as required, and thus the support frame 4 is releasably locked in the above-mentioned operating position. In this operating position, the various constituent elements mounted on the support frame 4 are located at predetermined positions within the copying machine main body 3, and these mechanical elements and various constituent elements mounted on the copying machine main body 3 are shown in FIG. The positional relationship shown in FIG. 2 and shown by the solid line in FIG. 2 (also shown in FIG. 3) is maintained, and the above-described copying process can be performed.

Although one specific example of the electrostatic copying machine configured according to the present invention has been described above, the present invention is not limited to this specific example, and various modifications and corrections can be made without departing from the scope of the present invention. It is possible.

<Effects of the Invention> In the electrostatic copying machine according to the first aspect of the present invention, the support frame, on which the transport switching mechanism and the copy sheet discharging means are mounted, is located at a predetermined position in the main body of the copying machine and outside the main body of the copying machine. When the support frame is in the working position, the fixing roller pair constituting the fixing device is held in the nip state, and the support frame is pulled out from the working position. Since the fixing mechanism is equipped with an operating mechanism that causes the fixing roller pair to be released from the nip state, the support frame is moved from the operating position to the pulling-out position, thereby making a copy in the transport switching path, the copy paper discharge path, and the copy paper return path. The paper can be easily removed, and even when a paper jam occurs in a state where it is nipped by the pair of fixing rollers that configure the fixing device, the copying machine main body and the support frame are not separated. The jammed copy paper can be easily removed through the space created in between.

Further, according to the second aspect of the present invention, a support frame body mounted on the main body of the copying machine so as to be movable between an operating position and a withdrawal position, and a support frame body provided between the open position and the closed position. An auxiliary frame mounted rotatably, a support switching mechanism and a copy paper discharging means are mounted on the support frame, and one of a pair of guide members defining a transfer switching path on the auxiliary frame. And a reverse feed roller that constitutes a feed reversing mechanism is mounted, and when the auxiliary frame is moved to the open position, the transport switching path and a part of the guide holding portion are opened. By positioning the auxiliary frame body at the open position after positioning at the draw-out position, a part of the transport switching path and the guide holding portion is opened, so even if a paper jam occurs in the transport switching path, etc. This jammed copy paper can be easily removed.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing a specific example of an electrostatic copying machine configured according to the present invention. 2 is a solid line showing the transfer switching mechanism of the electrostatic copying machine and its vicinity in FIG. 1 when the support frame is in the working position, and a two-dot chain line when the support frame is in the pull-out position. FIG. FIG. 3 is a partially enlarged cross-sectional view showing the fixing device and the transfer switching mechanism of the electrostatic copying machine of FIG. 1 and their vicinity in a state where the support frame is in the working position. FIG. 4 is a partially enlarged cross-sectional view showing the fixing device and the conveyance switching mechanism of the electrostatic copying machine of FIG. 1 and their vicinity in a state where the support frame is in the drawn-out position. 2 …… Housing 3 …… Copier main body 4 …… Supporting frame 8 …… Rotating drum 48 …… Copy paper feeding means 58 …… Copy paper transport path 108 …… Fixing roller pair 114 …… Transport switching mechanism 122 …… Copy paper discharge path 127 …… Feed reversing mechanism 140 …… Copy paper return path 216 …… Auxiliary frame 268 …… Actuating mechanism

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G03G 15/00 106 G03G 15/00 106 526 526 550 550 15/20 107 15/20 107 21/00 520 21/00 520

Claims (6)

(57) [Claims] 1. A copy paper conveying means for defining a copy paper carrying path, a copy paper supplying means for supplying copy paper to the copy paper carrying path, and a copy paper discharging means for defining a copy paper discharging path. A copy paper returning unit that defines a copy paper return path, and selectively guides the copy paper having an image formed on one side thereof while being conveyed through the copy paper conveyance path to the copy paper discharge path or the copy paper return path. A transport switching mechanism, a feed reversing mechanism for reversing the longitudinal direction of the copy paper when guiding the copy paper to the copy paper return path, and a copy paper returned through the copy paper return path. A copy paper retransmitting means for re-supplying the received copy paper to the copy paper transport path, and a fixing device arranged at the downstream end of the copy paper transport path for fixing the image formed on the copy paper surface, An electrostatic copying machine comprising: And the copy paper ejecting means is mounted on a support frame mounted on the main body of the copying machine, and the supporting frame body positions the transport switching mechanism and the copy paper ejecting means at a predetermined position in the main body of the copying machine. And a drawing-out position for positioning them outside the main body of the copying machine, and the fixing device is selectively fixed in a nip state in which they are in pressure contact with each other and in a nip release state in which they are released from each other. The fixing frame pair is held in the nip state when the support frame is in the working position, and the fixing frame pair is held when the support frame is positioned from the working position to the pull-out position. An electrostatic copying machine characterized by comprising an operating mechanism for releasing the nip. 2. One of the pair of fixing rollers is rotatably supported by a supporting member mounted so as to be swingable, and the operating mechanism moves the supporting member when the supporting frame is brought to the working position. When the support frame is held in the nip state by swinging in a direction approaching the other of the pair of fixing rollers, and when the support frame is brought to the pull-out position, the support member is removed from the other of the pair of fixing rollers. 2. The electrostatic copying machine according to claim 1, wherein the fixing roller pair is held in the nip-released state by swinging in a separating direction. 3. The actuating mechanism includes an action pin provided on the support frame and a swivel member pivotally mounted on the fixing device and having a cam groove for removably receiving the action pin. When the support frame is moved to the working position, the working pin is removably received in the cam groove of the turning member, and the turning member is turned in a predetermined direction to turn the one side of the fixing roller pair. Are moved in a direction close to the other of them, and when the support frame is brought to the withdrawn position, the action pin is disengaged from the cam groove of the pivot member,
3. An electrostatic copying machine according to claim 2, wherein one of the pair of fixing rollers is moved in a direction away from the other of the pair of fixing rollers by rotating the rotating member in a direction opposite to the predetermined direction. 4. An elastic member is interposed between the swiveling member and the supporting member, and when the supporting frame is brought to the working position, the elastic member is swung along with swiveling of the swiveling member in a predetermined direction. Claims: The support member is oscillated through a member in the direction of approaching the other of the pair of fixing rollers, and thus one of the pair of fixing rollers is elastically pressed against the other of the pair of fixing rollers. The electrostatic copying machine according to item 3. 5. A copy paper conveying means for defining a copy paper conveying path, a copy paper supplying means for supplying copy paper to the copy paper conveying path, and a copy paper discharging means for defining a copy paper discharging path. A copy paper returning unit that defines a copy paper return path, and selectively guides the copy paper having an image formed on one side thereof while being conveyed through the copy paper conveyance path to the copy paper discharge path or the copy paper return path. Transport switching mechanism that defines a transport switching path for storing the copy sheet, a guide holding unit that guides and holds the copy sheet guided to the copy sheet return path, and a copy sheet guided to the guide holding unit is reversed. A feeding reversing mechanism having a reverse feeding roller for feeding, and a copy paper retransmitting means for receiving the copy paper returned through the copy paper returning path and for re-supplying the received copy paper to the copy paper conveying path. In an electrostatic copying machine equipped with A support frame body movably mounted on the main body of the copying machine between an operating position to be positioned at a predetermined position inside the main body of the copying machine and a drawing position to be positioned outside the main body of the copying machine, and an open position and a closed position on the support frame body. An auxiliary frame body mounted so as to be rotatable between positions, the support frame body is provided with the transport switching mechanism and the copy paper discharging means, and the auxiliary frame body defines the transport switching path. One of the pair of guide members and the reverse feed roller that constitutes the feed reversal mechanism are mounted, and when the auxiliary frame is brought to the open position, the transport switching path and part of the guide holding portion are opened. The electrostatic copying machine characterized by the following. 6. The transport switching mechanism further includes a transport roller mechanism composed of an upper roller, an intermediate roller and a lower roller arranged in the vertical direction, and the transport roller mechanism switches the transport from the copy paper transport path. When the copy sheet is guided to the path, it is conveyed through the upper roller and the intermediate roller, and when the copy sheet is guided from the conveyance switching path to the copy sheet return path, it is conveyed between the intermediate roller and the lower roller. The nip between the upper roller and the intermediate roller is released when the upper roller of the transport roller mechanism is rotatably supported by the auxiliary frame body and the auxiliary frame body is moved to the open position. The electrostatic copying machine according to item 5.