A CLEANING UNIT OF A COPYING APPARATUS

Abstract: According to the cleaning unit of copying apparatus related to the invention, first, a part of photoreceptive drum and adjacent cleaning unit expose themselves by causing the part of copying apparatus to move in the direction at a right angle apart from the axis of photoreceptive drum. This allows a main charger installed to said cleaning unit to integrally be loaded into and unloaded from the copying apparatus together with the cleaning unit. The cleaning unit can be opened in the state of being secured to the copy­ ing apparatus by rotating it in the direction apart from the photoreceptive drum, and the main charger secured to the cleaning unit can also be opened by rotating it in the direc­ tion identical to that of the cleaning unit.

Description: Field of the Invention The present invention relates to an improved cleaning unit of a broad width industrial-use electrostatic process copying apparatus, and more particularly, to a mechanism for reasonably loading and unloading the cleaning unit and the main charger into and from an industrial-use electrostatic process copying apparatus. Description of the Prior Art Figs. 18 and 19 show lateral views of such an industrial-use electrostatic process copying apparatus. Of these, Fig. 18 is a simplified lateral view. Fig. 19 is a lateral view illustrating a condition in which a part of the copying apparatus is open to allow an operator to perform maintenance and inspection of a cleaning unit. When operating this conventional copying apparatus 1, a document is conveyed by document feeding rollers 2a and 2b. A document image radiated by a light source 3 is projected through a lens array 4 onto the surface of a photoreceptive drum 5. The surface of the photoreceptive drum 5 is uniformly charged with a positive charge by a main charger 6. Light corresponding to the document image passing through the lens array 4 radiates the positive charge. Then, the charge disappears from this portion thereby generating a static latent image. When the portion carrying the static latent image passes through a developing device 7 by rotation of the photoreceptive drum 5, toner adheres to the static latent image and eventually forms a toner image. Copying paper placed on a paper-feeding tray 8 is delivered to a feed roller assembly 11 through a paper-feed roller 9 and a resist roller assembly 10. The toner image formed on the surface of the photoreceptive drum 5 is transferred to the copying paper while the copying paper passes through a transfer device 13 between the photoreceptive drum 5 and a transfer charger 12. The copying paper bearing the toner image then passes through a fixing device 14 so that the toner image can be fixed. Then, the copying paper is transferred to a paper-discharge tray 16a via a paper-discharge roller 15. The resist roller assembly 10 is composed of an upper resist roller 10a and a lower resist roller 10b. The feed roller assembly 11 is composed of an upper feed roller 11a and a lower feed roller 11b. A cleaning unit 16 is installed at a position close to the external surface of the photoreceptive drum 5 for cleaning it by scraping off residual toner from the external surface of the photoreceptive drum 5. The cleaning unit 16 and the main charger 6 are independently installed in the conventional industrial-use copying apparatus 1 cited above. As a result, in order to perform maintenance and inspection of the cleaning unit 16 and the main charger 6, the copying apparatus is divided into two parts, i.e. a stationary part 1a and a movable part 1b, as indicated by dotted line 17. Movable part 1b can be moved to the position indicated by two-dot chained lines in Fig. 19. When the movable part 1b is moved, both the cleaning unit 16 and the main charger 6 are externally exposed for removal outside of the copying apparatus. The paper-discharge tray 16a, the paper-discharge roller 15 and the transfer device 13 are provided on the movable part 1b. Additionally, parts of the elements of the paper-conveying path (a part of a body of the copying apparatus) including the lower feed roller 11b, the transfer charger 12 and the upper resist roller 10a are provided on the movable part 1b. An opening 18 is formed by moving the movable part 1b at a right angle to the axis of the photoreceptive drum 5. Thus, the cleaning unit 16 can be extracted in the direction of arrow 19. The main charger 6 can also be extracted in the direction of arrow 20. As mentioned above, on any conventional industrial-use copying apparatus, opening 18 is generated by slidably moving the movable part 1b which constitutes a part of the body of the copying apparatus. Since either the cleaning unit 16 or the main charger 6 must discretely be taken out of the opening 18 or loaded into the copying apparatus through the opening 18, the operator is obliged to execute double handling operations. Furthermore, as shown in Fig. 19, since the main charger 6 is installed at a specific position hardly discernible from the opening 18, the operator is obliged to blindly install the lengthy main charger 6 to a specific position close to the photoreceptive drum 5. This is a major drawback, which may cause damage to the photoreceptive element on the surface of the photoreceptive drum 5. Summary of the Invention The primary object of the present invention is to simplify the process needed for loading and unloading a cleaning unit and a main charger and to prevent the surface of a photoreceptive drum from incurring damage by integrally combining the main charger with the cleaning unit so that the installation of the main charger can be completed simultaneously with the loading and unloading of the cleaning unit. On the other hand, normally, a main charger is cleaned at short cycles compared to the cleaning intervals of a cleaning unit 16, and yet, cleaning can be done simply. Thus, the operator has always to take out the main charger 6 together with the cleaning unit 16 whenever he needs to clean the main charger 6, which results in a lowered operating efficiency. To compensate for this, a further object of the present invention is to allow the operator to easily clean only the main charger 6 by holding the cleaning unit 16 in the state of being secured to the copying apparatus. It is desirable that the efficiency of the maintenance and the inspection be improved by allowing both the main charger 6 and the cleaning unit 16 to be integrally removed from the copying apparatus. To achieve this, a still further object of the present invention is to provide a mechanism which allows an operator to easily clean the main charger while holding the cleaning unit 16 in a position secured to the copying apparatus, and also to take out the main charger together with the cleaning unit from the copying apparatus. If in Figs. 18 and 19 the main charger 6 was combined with the cleaning unit 16, the operator could not clean the main charger 6 in this condition, since the opening of a case 6' of the main charger 6 faces in the direction of the axis of the photoreceptive drum 5. Consequently, the opening of the case 6' should be turned outwardly by rotating the main charger 6. However, the operator cannot do this because the main charger 6, when being rotated, would interfere with the cover of the light source 3. To compensate for this, a further object of the present invention is to provide a mechanical design which allows an operator to securely open the main charger 6 while being loaded inside of the copying apparatus without incurring disturbance of other component parts. The present invention, in conformity with one apsect thereof, provides for a cleaning unit of a copying apparatus which allows a part of a photoreceptive drum and a cleaning unit located adjacent to this drum to be externally exposed by causing a part of the copying apparatus to be moved in a perpendicular direction away from the axis of the photoreceptive drum, wherein a main charger and the cleaning unit form a combined unit so that the main charger can be loaded into or unloaded from the copying apparatus integrally with the cleaning unit, characterized in that a plurality of stays are provided on both sides of the bottom of said cleaning unit for supporting an operator's fingers when loading or unloading the combined unit into or from the copying apparatus. The subject invention, according to a further aspect thereof, provides for a cleaning unit of a copying apparatus which allows a part of a photoreceptive drum and a cleaning unit located ajacent to this drum to be externally exposed by causing a part of the copying apparatus to be moved in a perpendicular direction away from the axis of the photoreceptive drum, wherein a main charger and the cleaning unit form a combined unit which can freely be loaded into and unloaded from the copying apparatus and be rotated about pivots, characterized in that the main charger is rotably installed with respect to said cleaning unit to open it by rotating it in the same direction as the combined unit rotating away from the photoreceptive drum. Brief description of the Drawings Fig. 1 is a perspective view of a preferred embodiment of the cleaning unit of the present invention; Fig. 2 is a lateral view showing the action for setting the cleaning unit into a position close to a photoreceptive drum; Fig. 3 is a lateral view showing the state in which the cleaning unit is set to a position close to the photoreceptive drum; Fig. 4 is a plane view in conformity with arrow A of Fig. 3; Fig. 5 is a perspective view of a mechanism for preventing the cleaning unit from falling off; Fig. 6 (a) and 6 (b) are lateral views showing operating conditions of another preferred embodiment of the cleaning unit of the present invention; Fig. 7 (a) and 7 (b) are lateral views of essential coupling parts for explaining an engaging action of the cleaning unit of Fig. 6 with the copying apparatus; Fig. 8 is a perspective view of the cleaning unit showing the condition of loading operation in the copying apparatus; Fig. 9 (a) and 9 (b) are plane views for explaining the setting operation of the main charger; Fig. 10 (a) and 10 (b) are plane views of the coupling parts for explaining an engaging action of the main charger; Fig. 11 (a) and 11 (b) are lateral views for explaining the constitution of the turning center portion of the main charger; Fig. 12 (a) and 12 (b) are lateral views of the cleaning unit for explaining the loading operation of the cleaning unit shown in Fig. 6; Fig. 13 is a perspective view of still another preferred embodiment of the cleaning unit of the invention; Fig. 14 (a) and 14 (b) are lateral views of still another preferred embodiment of the cleaning unit showing the operating condition, Fig. 15 (a) and 15 (b) are lateral views of essential coupling parts for explaining the engaging action of the cleaning unit of Fig. 13 with the copying apparatus; Fig. 16 (a) and 16 (b) are lateral views illustrating the loading operation of the cleaning unit shown in Fig. 13; Fig. 17 (a) and 17 (b) are plane views for explaining the operations for loading the cleaning unit shown in Fig. 13; Fig. 18 is a simplified sectional view of a conventional industrial-use copying apparatus before opening the main body; and Fig. 19 is a simplified sectional view of a conventional industrial-use copying apparatus after opening the main body. Detailed description of the preferred embodiments Referring now more particularly to Fig. 1 through 17, preferred embodiments of the cleaning unit of the present invention will be described for better understanding of the invention. Those preferred embodiments described hereinbelow are merely examples of the invention, and thus, these by no means restrict the scope of the claims of the invention. As shown in Figs. 1 and 2, a cleaning unit 16 in conformity with a first preferred embodiment is provided with side plates 23a and 23b sandwiching between them a cleaning unit body 22. The side plates 23a and 23b are provided with a cutout portion 24 for mounting a main charger 6. A pair of charger-holders 26 substantially composed of a plate spring are secured to the upper surface of the cleaning unit body 22 by a screw 25. The charger-holders 26 support the main charger 6 so that it can freely slide in the longitudinal direction of the cleaning unit body 22. Handles 27 allow an operator to manually transfer the main charger 6. Lengthy holes 28 are provided in side plates 23a and 23b. A shaft 29 is inserted into holes 28 so that it can freely slide. A spring 30 constantly and elastically biases shaft 29 in the direction of the upper end of hole 28. A frame 1a' (shown in Fig. 13) of a stationary part 1a of the copying apparatus shown in Fig. 19 is provided with horizontal guide rails 31 as shown in Fig. 2. Guide pieces 32 slideably contact guide rails 31 and are secured to the external surface of the side plates 23a and 23b. Engaging portions 34 engaging supporting pins 33 on both sides of stationary part 1a are provided at the lower end of side plates 23a and 23b. Cutout portions 35 for accommodating the shaft 29 are provided in the frame 1a' of stationary part 1a as shown in Fig. 5. In addition, as shown in Figs. 3, 4 and 5, a control member 37 having a projection 36 at its tip portion is secured to the frame 1a' of the copying apparatus. The upper surface 37a of the control member 37 is set to a position where the bottom of a shielding case 6a of the main charger 6 comes into contact with the upper surface 37a when inserting a terminal 6b (shown in Fig. 1) of the main charger 6 into the connector of the copying apparatus by causing the main charger 6 in the set position to slide in the longitudinal direction. As shown in Fig. 5, a cutout portion 38 is provided at the edge of shielding case 6a. Cutout portion 38 faces the projection 36 when the main charger 6 is placed on the cutout portion 24. Next, the procedure of loading the cleaning unit 16 and the main charger 6 into the copying apparatus is described below. As shown in Fig. 1, first, an operator manually brings the main charger 6 into a position above the side plates 23a and 23b of the cleaning unit 21 which is disengaged from the copying apparatus. The operator then mounts the main charger 6 on the cutout portion 24 formed on the upper side of side plates 23a and 23b. The operator then inserts the main charger 6 between the charger-holder 26 and the cutout portion 24. In this state the handles 27 remain in contact with the upper surface of the shaft 29 as shown in Fig. 1. The operator then manually slides the main charger 6 in the direction of arrow 39 shown in Fig. 1 until it comes into contact with a stopper (not shown), the main charger 6 and the cleaning unit 16 now forming a combined unit 21. Next, the operator manually raises the combined unit 21, and then loads it into the copying apparatus of which a movable part 1b remains open as shown in Fig. 19. More specifically, as indicated by dotted line in Fig. 2, the combined unit 21 is installed by causing the guide pieces 32 of the side plates 23a and 23b to come into contact with the guide rails 31 installed on the frame 1a' of the copying apparatus. Next, the operator slides the combined unit 21 in the direction of a photoreceptive drum 5 while allowing the guide pieces 32 to remain in contact with the guide rails 31. This causes the engaging portions 34 on the side plates 23a and 23b to be engaged with the supporting pins 33. This state is shown in Fig. 2 by means of one-dot chained lines. When the engaging portions 34 are engaged with the supporting pins 33, the operator then turns the combined unit 21 in the counterclockwise direction with supporting pins 33 serving as pivots as shown in Fig. 2. Then, the shaft 29 is inserted through the cutout portions 35 (Fig. 5) of the frame 1a' of the copying apparatus. The shaft 29 is compulsorily held in the coutout portions 35 by an elastic force generated by the spring 30 so that the combined unit 21 can be held by the frame 1a' via the shaft 29. Since a lateral surface of the guide pieces 32 remains in contact with a bearing 40 supporting the photoreceptive drum 5 when the combined unit 21 is loaded as shown in Fig. 3, the position of the combined unit 21 in the set condition is securely determined. On the other hand, when disengaging the shaft 29 from the cutout portions 35 by lowering the position of the shaft 29 against the push-up force of the spring 30, the combined unit 21 can be rotated in the clockwise direction, wherein combined unit 21 pivots about supporting pins 33 as shown in Fig. 2. When rotating the combined unit 21 around the supporting pins 33, the projection 36 of the control member 37 on the frame 1a' interferes with the shielding case 6a of the main charger 6. Nevertheless, when this state is present, since the cutout portion 38 formed on the shielding case 6a is in a position opposite to the projection 36, the projection 36 passes through the cutout portion 38, so that no interference can take place. When the combined unit 21 is secured in the predetermined position against the photoreceptive drum 5 as shown in Fig. 3, the projection 36 of the control member 37 is at a position where it remains in contact with an external side surface of the shielding case 6a. While this state is present, the operator can manually operate the handles 27 to move the main charger 6 in a direction opposite to arrow 39 shown in Fig. 1. Movement of the main charger 6 allows the terminal 6b to be connected to a connector 6c on the copying apparatus. Since cutout portion 38 simulataneously moves from the position facing the projection 36, the projection 36 directly comes into contact with the external side surface of the shielding case 6a. As mentioned above, when the terminal 6b of the main charger 6 is inserted into the connector 6c on the copying apparatus, even if the operator tries to extract the combined unit 21 by rotating it in the clockwise direction as shown in Fig 3 after disengaging the shaft 29 from the cutout oportion 35, the projection 36 remains engaged with the external side surface of the shielding case 6a to inhibit rotation of the combined unit 21. This prevents the operator from erroneously removing the combined unit 21 while the terminal 6b is inserted in the connector 6c. After securing the combined unit 21 at a specific position about the photoreceptive drum 5, the movable part 1b, which was in the open state shown in Fig. 19, is closed as shown in Fig. 18. This allows the copying operation to be resumed. As mentioned above, before closing the movable part 1b, the main charger 6 must correctly be connected to the connector 6c. To achieve this, it is desirable to inhibit a closing operation by causing a part of the movable part 1b to come into contact with the main charger 6 and the handle 27 when closing the movable part 1b while the main charger 6 is at a position in which it is incorrectly connected to the connector 6c. In this case, if the main charger 6 is correctly connected to the connector 6c, the part of the movable part 1b passes through a cutout portion (not shown) of the main charger 6 or smoothly moves without being interfered by the handle 27. The main charger 6 and the cleaning unit 16 are removed from the copying apparatus as combined unit 21 merely by reversing the operations mentioned above. As mentioned above, the above preferred embodiment integrally combines the main charger 6 with the cleaning unit 16 and allows the cleaning unit 16 to move to a position where it is engaged with the supporting pin 33. Then, the cleaning unit 16 can be secured in the predetermined position merely by allowing the operator to manually raise it. The combined unit 21 composed of the main charger 6 and the cleaning unit 16 can securely be connected to the copying apparatus merely by sliding the main charger 6 in the manner mentioned above. Consequently, the above preferred embodiment dispenses with the troublesome process otherwise needed for discretely loading and unloading the cleaning unit 16 and the main charger 6 into and from the copying apparatus. Furthermore, the operator can easily and securely load the main charger 6 which should be installed to a hardly discernible position, and thus, the above preferred embodiment eliminates potential risk of damaging the photoreceptive drum caused by unwanted contact with the main charger. The cleaning unit 16 is provided with stays 22a, 22b which are not illustrated in Figs. 1 to 5 but which are described in detail below in connection with Figs. 13 to 17. By virtue of the mechanical constitution of the cleaning unit of the above preferred embodiment, loading and unloading of the cleaning unit 16 and the main charger 6 can easily be done merely by loading and unloading the cleaning unit, and as a result, the efficiency in the execution of a maintenance and an inspection can be improved. Furthermore, the operator can freely perform the maintenance and the inspection in an open and spacious location, thus promoting operating efficiency. Compared to the case of loading und unloading the main charger alone, the operator can drastically promote the convenience in handling the main charger which should be installed to a hardly discernible position. As a result, the potential risk of incurring damage to the photoreceptive drum caused by unwanted contact with the main charger is eliminated. Referrring now to Figs 6 through 11, another preferred embodiment of the cleaning unit of the invention is described below. As shown in Fig. 8, a cleaning unit 116 in conformity with this preferred embodiment is also provided with the side plates 23a and 23b sandwiching between them the cleaning unit body 22. The side plates 23a and 23b are provided with the cutout portions 24 for mounting the main charger 6. In addition, the side plates 23a and 23b are respectively provided with the supporting holes 125a and 125b which support a shaft 125 which freely slides in the longitudinal direction and freely rotates. The main charger 6 is secured to the tip ends of a pair of brackets 126a and 126b which are rotatably mounted on shaft 125. However, these brackets 126a and 126b cannot slide in the longitudinal direction of the shaft 125. The main charger 6 can integrally be taken out of the cleaning unit 116 together with the brackets 126a and 126b. A pair of handles 127a and 127b are used for sliding the shaft 125. The handles 127a and 127b are idly inserted in guide slits 129a and 129b of brackets 128a and 128b of the cleaning unit body 22 so that said shaft 125 can be moved in the longitudinal direction thereof. The guide slits 129a and 129b are respectively composed of lengthy slits 129a' and 129b' and of short slits 129a'' and 129b'' shown in Fig. 10 (a) and (b). The lengthy slit 129a' (129b') is provided with a length longer than that of the short slit 129a'' (129b''). The shaft 125 moves in the direction of arrow X shown in Fig. 8 by a long distance when the handle 127a (127b) is coupled to the lengthy slit 129a' (129b') rather than being coupled to the short slit 129a'' (129b''). Fig. 9 (a) represents the condition in which the handle 127a (127b) is inserted into the lengthy slit 129a' (129b'). Fig. 9 (b) represents the state in which the handle 127a (127b) is inserted into the short slit 129a'' (129b''). The shaft 125 is elastically biased by a spring 130 (energizing means) in the direction of arrow X shown in Fig. 8. As in the first preferred embodiment, the frames 1a' of the stationary part 1a of the copying apparatus are provided with the guide rails 31 which extend in the horizontal direction as shown in Figs. 6 and 8. The guide pieces 32 coming into contact with the guide rails 31 are secured to the external surfaces of the side plates 23a and 23b. Guide slits 34a and 34b are provided in the frames 1a' for guiding and receiving the supporting pins 33 externally projecting from the side plates 23a and 23b. The guide slits 34a and 34b have a width d₁ and are provided with an L-shape. The lower part of the guide slits 34a and 34b is formed with a round shape having an internal diameter which is slightly wider than external diameter D₁ of the supporting pins 33. A bevelling 33' having a width narrower than d₁ is provided at the edge of the supporting pins 33. The guide slit 34a (34b) is composed of a level lower part and an inclined part at the inlet side thereof. The width of the level part is identical to the width d₁, while the inclined part is wider than d₁ and narrower than D₁ to allow said bevelling 33' to pass through this portion in a tilted state. A supporting hole 41a is formed at an end of the frame 1a' as shown in Fig. 8. When the shaft 125 moves in the direction of arrow X while the cleaning unit 116 is raised by the operator until the guide piece 32 comes into contact with the bearing 40 of the photoreceptive drum 5, an end 125' of this shaft 125 is inserted into the supporting hole 41a. As shown in Figs. 8 and 9, a narrow-diameter portion 42a and a wide-diameter portion 42b are provided at the other end of the shaft 125. As shown in Fig. 8, a supporting hole 41b (shown in Fig. 11(a)) which allows entry of the wide-diameter portion 42b is provided in the frame 1a' which is opposite to the frame 1a' having the supporting hole 41a. A cutout portion 41b' which is obliquely open in the downward direction is connected to the supporting hole 41b. The cutout portion 41b' is slightly wider than the narrow-diameter portion 42a. The supporting holes 41a and 41b constitute a means for engaging and disengaging the shaft 125 in this preferred embodiment. Next, the sequential procedure for loading the cleaning unit 116 and the main charger 6 into the copying apparatus is described below. When the cleaning unit 116 is out of the copying apparatus, as shown in Figs. 8 and 10 (b), the handles 127a and 127b attached to the shaft 125 are inserted in the short slits 129a'' and 129b''. When the shaft 125 supported by the supporting holes 125a and 125b is urged by the spring 130 in the direction of arrow X, shaft 125 will assume the position shown in Figs. 8 and 9(b). While this state is present, the operator loads the cleaning unit 116 and the main charger 6, which form a combined unit 121, into the copying apparatus 1 of which the movable part 1b remains open as shown in Fig. 19. Concretely, the operator loads the guide pieces 32 and the supporting shafts 33 onto the guide rails 31 of the frames 1a' of the copying apparatus. This allows the cleaning unit 116 to be held by the guide pieces 32 and the supporting shafts 33. Then, the operator moves the cleaning unit 116 in the direction of arrow Y shown in Fig. 8. This causes the supporting shafts 33 to be inserted into the guide slits 34a and 34b. As mentioned above, since the bevelling 33' shown in Fig. 7 is provided at both ends of the supporting shafts 33, these supporting shafts 33 can smoothly enter into the guide slits 34a and 34b until reaching the bottom thereof. This state is shown in Fig. 6 (a). In this state the main charger 6 is apart from the photoreceptive drum 5 by a sizable distance. To compensate for this, the operator rotates the combined unit 121 in the direction of arrow Z shown in Fig. 6 (b) to the position illustrated in this Figure. The operator keeps on rotating the combined unit 121 until the guide piece 32 comes into contact with the bearing 40 of the photoreceptive drum 5. The position at which the guide piece 32 comes into contact with the bearing 40 exactly corresponds to the position at which the cleaning unit 116 is correctly set. Concurrently, the main charger 6 is also correctly set to a position at a proper distance from the photoreceptive drum 5. However, the main charger 6 can be set to the correct position only after moving further in the direction at right angle towards a paper surface in Fig. 6 (b), i.e. in X-direction. While the operator keeps on rotating the cleaning unit 116 unitl reaching the state shown in Fig. 6 (b), the supporting shaft 33 is also rotated until reaching the state shown in Fig. 7 (b). As a result, the supporting shaft 33 having the external diameter D₁ cannot reach the end (having the width d₁) of the guide slit 34a (34b), and thus, in this state the combined unit 121 cannot be taken outside. When this state is present, the operator slightly moves the shaft 125 in the direction opposite to the direction of arrow X against the force of the spring 130. This allows the handles 127a and 127b to be disengaged from the short slits 129a'' and 129b''. As a result, the operator can transfer the handles 127a and 127b from the short slits 129a'' and 129b'' to the lengthy slits 129a' and 129b' by slightly rotating the shaft 125 in the clockwise direction as shown in Fig. 6 (b) (see Fig. 10 (a)). Consequently, the handles 127a and 127b are disengaged from the short slits 129a'' and 129b'', and then, handles 127a and 127b move through the lenghty slits 129a' and 129b' in the direction of arrow X shown in Fig. 8 until they reach positions beyond those positions restricted by the short slits 129a'' and 129b''. As shaft 125 moves on, the tip end 125' of the shaft 125 is inserted into the supporting hole 41a. Simultaneously, the wide-diameter portion 42b at the opposite end of the shaft 125 is inserted into the supporting hole 41b, and as a result, the wide-diameter portion 42b cannot be disengaged from the cutout portion 41b'. Fig. 11(a) represents this state. Fig. 11(b) represents the state in which the narrow-diameter portion 42a is inserted into the supporting hole 41b through the cutout portion 41b'. In this way, the shaft 125 is inserted into the supporting holes 41a and 41b, and yet, removal of the shaft 125 from these holes is securely prevented. This allows the cleaning unit 116 to firmly be fixed in position in the state shown in Fig. 6 (b). Since the shaft 125 moves in the direction of arrow X, the terminal 6b (connector means) of the main charger 6 is inserted into a socket (not shown) on the copying apparatus, and thus, the main charger 6 is secured in the position shown in Fig. 6 (b). By reversing the sequential steps mentioned above, the combined unit 121 of the cleaning unit 116 and the main charger 6 can be removed from the copying apparatus. This securely promotes efficiency for executing the maintenance or the inspection of the cleaning unit 116 or the main charger 6. Next, the process for opening the main charger 6 loaded in the copying apparatus for cleaning is described below. First, using the handles 127a and 127b, the operator moves the shaft 125 in the direction opposite to the direction of arrow X as shown in Fig. 8 by reversing the steps mentioned above. This causes the terminal 6b of the main charger 6 to be disengaged from the socket (not shown). Simultaneously, the tip end 125' of the shaft 125 is disengaged from the supporting hole 41a, while the wide-diameter portion 42b at the other tip end of the shaft 125 is also disengaged from the supporting hole 41b, and instead, the narrow-diameter portion 42a is inserted into the supporting hole 41b as shown in Fig. 11(b). Thus, the shaft 125 is freed from the supporting holes 41a and 41b. As a result, the cleaning unit 116 can be rotated in the direction opposite to the direction of arrow Z shown in Fig. 6 (b), to cause the guide piece 32 to leave the bearing 40 and then come into contact with the guide rail 31 as shown in Fig. 6 (a). Rotation of the cleaning unit 116 allows the main charger 6 to avoid contact with other parts, for example the cover of a light source 3 shown in Fig. 19, so that no interference occurs with these parts. Consequently, the main charger 6 can be rotated about the shaft 125 up to the predetermined position shown by one-dot chained lines in Fig. 6 (a). Finally, an opening of the main charger 6 turns upward to allow the operator to easily clean the main charger 6. By reversing the steps mentioned above, the opened main charger 6 can be closed and the combined unit 121 can easily be reinstalled inside of the copying apparatus. This preferred embodiment allows the operator to easily clean the main charger 6 at frequent intervals while keeping it loaded inside of the copying apparatus. This promotes the efficiency of a cleaning operation. The invention provides a useful cleaning unit which allows the operator to easily clean the main charger at frequent intervals while keeping it loaded inside of the copying apparatus, and the operator can easily load and unload the integrally combined unit of the cleaning unit and the main charger for efficiently and reasonably performing the maintenance and the inspection at frequent intervals, thus significantly promoting overall efficiency in performing cleaning, the maintenance and the inspection. After separating the main charger from adjacent component parts by rotating the cleaning unit, the operator can turn the opening of the main charger in the external direction by rotating the main charger so that cleaning can easily be done. As a result, the operator no longer incurs inconvenience in performing cleaning of the main charger caused by interference between the main charger and adjacent component parts of the copying apparatus. When either loading or unloading the cleaning unit 116 shown in Fig. 8 into or from the copying apparatus, normally, the operator grasps the cleaning unit 116 by holding the shaft 125 with thumb and the bottom of the cleaning unit body 22 with other fingers. However, since there is no guiding object stopping the movement of the fingers at the bottom of the cleaning unit body 22, the operator may deeply insert his fingers into the cleaning unit 116, and as a result, any of his fingers may come into contact with the surface of the photoreceptive drum 5 as shown in Fig. 12 (a) and (b). On the other hand, the operator cannot easily grasp a cleaning unit if it has a sizeable width. For example, if the operator holds the center of the cleaning unit body 22 with a single hand and the edge of either side with the other hand, due to unstable weight balance, the operator may feel it difficult to correctly load or unload the combined unit 121. To solve this problem, the invention also provides another preferred embodiment of a cleaning unit which prevents the fingers of the operator from coming into contact with the photoreceptive drum 5 when loading or unloading the combined unit 121 and provides convenience for the operator when holding a cleaning unit having a sizable width, the details of which are described below. The cleaning unit 216 of this preferred embodiment, as shown in Figs. 13 through 17, has a basic constitution which is similar to that of the cleaning unit 116 of the preceding embodiment shown in Figs. 6 through 11. Different from cleaning unit 116 the cleaning unit 216 is provided with stays 22a and 22b on both sides of the bottom of the cleaning unit body 22 for catching the operator's fingers when loading or unloading the cleaning unit 216 into or from the copying apparatus. Particularly, as shown in Fig. 13, the side plates 23a and 23b sandwiching between them the cleaning unit body 22 of the cleaning unit 216 of this preferred embodiment are respectively provided with the projecting stays 22a and 22b. The stays 22a and 22b may substantially be provided at both sides of the bottom of the cleaning unit body 22. The dimensions of the stays may differ from each other. However, from the viewpoint of balance between both hands, the stays preferably should be disposed in symmetry at the right and left sides. The cleaning unit 216 of this preferred embodiment has frames 1a' which are provided with L-shaped guide slits 134a and guide ribs 134b, wherein the guide slit 134a guides a pin 133a of a supporting shaft 133 which externally projects from the side plates 23a and 23b, whereas the guide rib 134b supports a boss 133b of the supporting shaft 133. Next, the sequential procedure for loading the cleaning unit 216 into the copying apparatus is described below. When the cleaning unit 216 is disengaged from the copying apparatus, the handles 127a and 127b attached to the shaft 125 are respectively engaged with the short slits 129a'' and 129b'' as shown in Figs. 10 (b) and 13. When the shaft 125 held by the supporting holes 125a and 125b is urged in the direction of arrow X by the spring 130, the shaft 125 assumes the position shown in Figs. 13 and 17 (b). In this state, the operator manually holds the cleaning unit 216 together with the main charger 6 using his fingers in contact with the stays 22a and 22b asd shown in Fig. 16. Then he loads the integral unit 221 comprising the cleaning unit 216 and the main charger 6 into the copying apparatus 1 through the opening defined by the movable part 1b. Particularly, first, the operator places the supporting shaft 133 on the guide rail 31 of the frame 1a'. Consequently, the cleaning unit 216 is held by the shaft 133. Then, the operator moves the cleaning unit 216 in the direction of arrow Y shown in Fig. 13. This causes the boss 133b of the supporting shaft 133 to be held by the guide rib 134b, and as a result, the pin 133a of the shaft 133 is inserted into the guide slit 134a. Since the guide rib 134b guides the boss 133b, the pin 133a can easily and smoothly enter into the lower part of the guide slit 134a. Figs. 13, 14 (a), and 16 (a) show this state. Figs. 15 (a) and (b) show the position of the supporting shaft 133. When the above state is reached, the main charger 6 is spaced from the photoreceptive drum 5 by a sizeable distance. Then the operator rotates the cleaning unit 216 at this remote position in the direction of arrow Z as shown in Fig. 16 (b). The further loading steps are similar to those of the combined unit 121 of the preceding embodiment. This preferred embodiment provides a novel cleaning unit of the copying apparatus, which can manually be loaded into and unloaded from the predetermined position close to the photoreceptive drum and includes the provision of a plurality of stays on both sides of the bottom of the cleaning unit body for catching the operator's fingers when either loading or unloading the cleaning unit. Consequently, the operator can stop the movement of his fingers at the position of these stays when grasping the cleaning unit, thus securely preventing his fingers from coming into contact with the surface of the photoreceptive drum. In addition, since the stability of the handling operation is promoted, the operator can easily load or unload a broad cleaning unit into or from the copying apparatus. It should be understood that the design of the cleaning unit 216 of this preferred embodiment is also applied to the cleaning unit 16 (shown in Fig. 1).

Claims: A cleaning unit of a copying apparatus (1) which allows a part of a photoreceptive drum (5) and a cleaning unit (16, 216) located adjacent to said drum to be externally exposed by causing a part of the copying apparatus to be moved in a perpendicular direction away from the axis of the photoreceptive drum, wherein a main charger (6) and said cleaning unit form a combined unit (21, 221) so that said main charger can be loaded into or unloaded from the copying apparatus integrally with the cleaning unit, characterized in that a plurality of stays (22a, 22b) are provided on both sides of the bottom of said cleaning unit for supporting an operator's fingers when loading or unloading said combined unit into or from the copying apparatus. A cleaning unit of a copying apparatus (1) which allows a part of a photoreceptive drum (5) and a cleaning unit (116, 216) located adjacent to said drum to be externally exposed by causing a part (1b) of the copying apparatus to be moved in a perpendicular direction away from the axis of the photoreceptive drum, wherein a main charger (6) and said cleaning unit form a combined unit (121, 221) which can freely be loaded into and unloaded from said copying apparatus and be rotated about pivots (33, 133), characterized in that said main charger (6) is rotatably installed with respect to said cleaning unit (116, 216) to open it by rotating it in the same direction as the combined unit rotating away from the photoreceptive drum. A cleaning unit according to claim 2, comprising a shaft (125) which is secured to said cleaning unit (116, 216) so as to slide in the longitudinal direction (X) of said cleaning unit and to rotate around its axis; a main charger (16) which is installed to be able to rotate around said shaft (125); energizing means (130) for constantly energizing said shaft in the longitudinal direction of said cleaning unit; shaft-positioning means (127a, 127b, 128a, 128b) which sets contact positions of the shaft at two stages by the aid of the energizing means; shaft-engaging and disengaging means (41a, 41b) which allows both ends of said shaft to be engaged when said shaft is set to one of the contact positions (129a', 129b') and to be disengaged when said shaft is set to the other contact position (129a'', 129b''); and connector means (6b) which is installed to an end of said main charger (6) and inserted into the socket (6c) of the copying apparatus when said main charger is set to the former contact position (129a', 129b') together with said shaft (125).

Inventors: KAJITA, HIROSHI, SUGIURA, MAKOTO, TAKEMOTO, MITSUTOSHI
Applicants: MITA INDUSTRIAL CO. LTD.
Application year: 1988
Main classification: G03G21
IPC codes: G03G21, G03G15