Feeding device

Abstract: A feeding device according to the invention, comprising: a cassette (26, 27) capable of being mounted in and removed from the main body of a copying machine to which the feeding device is adapted; a pivotal paper holding plate (34) which is disposed within the cassette and capable of being raised; a lift member (40) for raising the pivotal paper holding plate (34), disposed under the pivotal paper holding plate (34) so as to pivot on a vertical plane; a rotary lift-up member (60) for allowing the lift member (40) to pivot thereon, the lift member (40) being secured to the rotary lift-up member (60); a driving device (42) for transmitting a driving force to the rotary lift-up member (60); and a coupling device (44, 45) interposed in the driving device (42), for effecting and suspending the transmission of the driving force for rotating the rotary lift-up member (60), wherein when the cassette (26, 27) is taken out from the main body, the lift member (40) pivots downward due to its own weight, thereby releasing the pivotal paper holding plate (34) from its raised condition. With such an arrangement, even if the cassette (26, 27) is taken out from the main body when the pivotal paper holding plate (34) is in its raised condition, the paper feeding end of the pivotal paper holding plate (34) can be prevented from touching with the paper feed mechanism disposed within the main body, thereby avoiding damage to the contacted parts.

Description: FIELD OF THE INVENTION The present invention relates to a feeding device for an apparatus such as a copying machine, a laser printer, and an overhead projector, the feeding device being capable of feeding copy material laterally or longitudinally oriented with respect to a feeding direction. More particularly, the invention relates to a feeding device that has a pivotal copy material holding plate for lifting up copy material, the holding plate being let down when a copy material storing unit of the feeding device is removed from the main body of the apparatus. BACKGROUND OF THE INVENTION There are conventionally known copying machines provided, under the main body thereof, with a desk for accommodating several paper feed cassettes in tiers. Those copying machines are capable of storing copy papers of various sizes in the cassettes, feeding paper laterally or longitudinally oriented, and automatically selecting paper to be fed, thereby reducing the operation required for changing papers to be used (see Japanese Patent Publication Laid-Open No. 192637/1986 (Tokukaisho 61-192637)). In such an apparatus, it is essential that a top sheet in a stack of copy papers stored in the cassette be lifted up until it comes in contact with a pick-up roller, in order to be picked up and sent out by the pick-up roller. Several approaches to meet the above requirement have been provided. For example, Japanese Patent Publication Laid-Open No. 59245/1981 (Tokukaisho 56-59245) and Japanese Patent Publication Laid-Open No. 59251/1981 (Tokukaisho 56-59251) disclose a paper feed cassette having a paper holding plate that is pivotally disposed for lifting up paper and a lever for raising the paper feeding end of the holding plate. However, when the above arrangement is employed in a copying machine having a cassette that can be mounted in and removed from the main body of the copying machine for supplying paper in the cassette or settling a paper jam, if the cassette is taken out from the main body with the pivotal paper holding plate being raised, the paper feeding end of the holding plate touches with the feeding mechanism provided in the main body, resulting in damage to both holding plate and feeding mechanism. Another principle is disclosed by DE-A1-3 403 456 wherein a lifter provided in the main body raises a sheet support plate accommodated in a cassette so that the sheet on the sheet support plate is fed through a pick-up roller. During withdrawing the cassette from the main body, the cassette must be raised at the outer end causing a lever system to lower the sheet support plate. The complicated structure of the lever system accommodated in the main body of the apparatus, and the indefinite frictional behaviour of the levers leads to unreliable operation of the system whereby a feeding roller keeps contact with the sheet or the sheet support plate causing damage of the feeding roller. Summary of the Invention The present invention aims to provide a feeding device with high compactness and reliability, with a copy material feed unit removable from the main body of an apparatus to which the feeding device is adapted, without raising the outer end of the copy material feed unit. The solution for achieving the above object is given in the characterizing part of claim 1. The feeding device of the present invention is characterized in that driving means and parts of means for arresting the driving force are provided within said removable copy material feed unit and that corresponding parts of said means for arresting the driving force are provided within the main body of said apparatus. Such an arrangement improves compactness of the copy material feed unit resulting in a high reliability of releasing the copy material holding plate from its raised condition. With such an arrangement, even if the copy material feed unit is taken out - from the main body of the apparatus for supplying copy paper or settling a jam when the pivotal copy material holding plate is in a raised condition, the paper feeding end of the holding plate can be prevented from touching with the feeding mechanism disposed within the main body so that damage to the contacted parts can be avoided, since the holding plate is released from its raised condition in cooperation with the removal of the copy material feed unit from the main body. The invention and its various advantages will become more apparent to those skilled in the art from the ensuing detailed description of preferred embodiments, reference being made to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Figs. 1 to 6 show one preferred embodiment of the present invention. Fig. 1 is a perspective view showing a rotatable cassette. Fig. 2 is a plan view showing the rotatable cassette in which coupling parts of a first coupling and a second coupling are disengaged when the rotatable cassette is removed. Fig. 3 is a schematic front view of a copying machine showing the internal structure thereof. Fig. 4 is a plan view of a feeding mechanism. Fig. 5(a) is a side view of the feeding mechanism. Fig. 5(b) is a side view of the feeding mechanism wherein paper pushing back member is actuated. Figs. 6(a) to 6(d) are the plan view of the rotatable cassette respectively showing the rotation of the rotatable cassette. DESCRIPTION OF THE EMBODIMENTS Referring now to Figs. 1 to 6, one embodiment of the present invention will be described below. As shown in Fig. 3, a document glass plate 2 of a copying machine 1 is provided with an automatic document feeder 3 (hereinafter referred to as "ADF"). The ADF 3 conveys a document (not shown) from a document tray 3a to a position on the document glass plate 2, the position being predetermined in accordance with the size and orientation ("lateral orientation" or "longitudinal orientation" with respect to a paper feed direction) of the document, and ejects the document outward after the completion of the copying operation. In the case of duplex copying operation, the ADF 3 turns over the document one face of which has been copied, conveys it onto the predetermined position on the document glass plate 2 again and ejects it outward after both faces are copied. The document tray 3a is provided with detection switches 4 and 5 for detecting the size of a document placed on the document tray 3a. Under the document glass plate 2 is provided an optical system 6 comprising a plurality of reflection mirrors 6a and a plurality of lenses 6b. The optical system 6 basically functions to guide the optical image of a document onto a photosensitive drum 7 and has a function of varying magnification in order to perform enlarging copying and reducing copying, in addition to real-size copying. Around the photosensitive drum 7 are disposed a cleaner 8, a static eliminating charger 9, a main charger 10, a developing device 11 in which toners for full color copying are stored and a developing device 12 in which black toner is stored. With those members, a series of operations, that is, the removal of residual toner from the photosensitive drum 7, static elimination, electrification, exposure (performed by the optical system 6), and development are performed in this order. There are provided a transferring charger 13, and a separating charger 14 under the photosensitive drum 7. When a copy paper (copy material) not shown in the drawing passes between the photosensitive drum 7 and the transferring charger 13, a toner image formed on the photosensitive drum 7 is transferred onto the paper by the transferring charger 13. The paper is then separated from the photosensitive drum 7 by the separating charger 14 and conveyed by a conveyor belt 17 to a fixing device 18 which fixes the toner on the paper by heating or pressurizing. After passing through the fixing device 18, the paper is basically ejected outside the main copy machine 1, that is, discharged onto one of a plurality of paper receiving trays 19a via the sorter 19. When duplex copying or composite copying is performed, the paper that has passed through the fixing device 18 passes through a paper return path 20 and is guided to a duplex/composite unit 21. In the case of duplex copying, the paper is turned over and placed on an intermediate tray 21c after passing through a first delivery path 21a within the duplex/composite unit 21. The paper then is sent out to a paper feed path 22 by a forwarding roller 21d. In the case of composite copying, the paper that has been guided to the duplex/composite unit 21 is sent to a second delivery path 21b within the unit 21 and after the trailing edge of the paper is detected thereat, the paper returns and is backwardly guided to the first delivery path 21a. Thereafter, the paper is turned over so as to be placed on the intermediate tray 21c, and then sent out by the forwarding roller 21d to the paper feed path 22. The paper feed path 22 is a path for guiding a paper to the photosensitive drum 7 and is provided, at the forward end thereof, with a paper stop roller 15 for determining timing for rotating the photosensitive drum 7 and sending out a paper. The paper feed path 22 is connected to a plurality of paper feed means from which paper is appropriately fed. More concretely, in an ascending scale, there are installed in the copying machine a first fixed cassette 25, a first rotatable cassette 26, a second rotatable cassette 27, the duplex/composite unit 21, a second fixed cassette 28, a third fixed cassette 29, and a manual paper feeder 30. The first fixed cassette 25, the second fixed cassette 28 and the third fixed cassette 29 (these cassettes are copy material feed units) are respectively detachable from the copying machine 1. The first rotatable cassette 26 and the second rotatable cassette 27 (these cassettes are copy material feed units) are detached together with their bed-plates 31 from the copying machine 1. As shown in Fig. 1, the first and second rotatable cassettes 26 and 27 are respectively provided with the bed-plate 31 which is a housing for the cassette, having a washer 31a secured thereto. At the washer 31a, a pivot pin 31b is vertically disposed. One end of an arm 32 is supported by the pivot pin 31b such that the arm 32 horizontally pivots on the pivot pin 31b. At the other end of the arm 32, there is vertically disposed a pivot pin 32a by which a rotating section 35 (copy material orientation changing means) is pivotally supported. The rotating section 35 has a two-sheet structure, comprising a paper feed base 33 (copy material feed base) and a pivotal paper holding plate 34 (pivotal copy material holding plate) positioned on the paper feed base 33. The rotating section 35 turns through 90° thereby conveying copy papers stacked on the pivotal paper holding plate 34 to a position from which paper laterally oriented with respect to a feed direction is fed (the position is hereinafter referred to as "lateral feed position") or a position from which paper longitudinally oriented with respect to the same is fed (the position is hereinafter referred to as "longitudinal feed position"). The position at which one end of the arm 32 is pivotally supported by the pivot pin 31b is so determined that when the stack of papers are rotatively conveyed to the lateral feed position or longitudinal feed position, the center of the papers is always located on the pivot pin 32a. The paper feed base 33 is provided with wall portions 33a, 33b, 33f and 33e. The wall portions 33a, 33f and 33e define, together with the pivotal paper holding plate 34, a paper stacking position for lateral feed (lateral copy material stacking position), and function to prevent a stack of copy papers from shifting from the above position when the papers are laterally fed. On the other hand, the wall portions 33b, 33e and 33f define, together with the pivotal paper holding plate 34, a paper stacking position for longitudinal feed (longitudinal copy material stacking position), and prevent stacked papers shifting from the above position when they are longitudinally fed. The wall portions 33a and 33b are integrally formed with the paper feed base 33, vertically raising therefrom. Each of the wall portions 33a and 33b is provided with an opening 33c at the substantially central part thereof. The opening 33c turns, extending a predetermined distance toward the center of the paper feed base 33. When the rotating section 35 is set in either of the feed positions, a lift member 40 is located beneath the opening 33c and when the lift member 40 is pivoted upward in this condition, the lift member 40 can be brought into contact with the bottom face of the pivotal paper holding plate 34, passing through the opening 33c. The structure of the lift member 40 will be later described in detail. The wall portions 33f and 33e are secured to the upper face of the paper feed base 33, facing to the wall portions 33a and 33b respectively. The wall portion 33f raises passing through an opening 34b and the wall portion 33e raises passing through an opening 34a, these openings 34a and 34b being provided for the pivotal paper holding plate 34. Therefore, the wall portions 33f and 33e do not interfere with the raising movement of the pivotal paper holding plate 34. The pivotal paper holding plate 34 is provided with inclined parts 34f and 34g which respectively bend forwardly. When the holding plate 34 is raised by the lift member 40 for longitudinal feed, the inclined part 34f makes an optimum tilt angle for feeding paper to the main body of the copying machine 1. Similarly, when the holding plate 34 is raised for lateral feed, the inclined part 34g makes an optimum tilt angle. At one corner of the pivotal paper holding plate 34, there is provided a supporting segment 34c outwardly bending from the upper end of the wall portion 34d. At that corner, the trailing end of paper comes in contact in both cases paper is placed in the paper stacking position for lateral feed and the paper stacking position for longitudinal feed. The supporting segment 34c is provided with a supporting member 36 for supporting the pivotal paper holding plate 34 at one point. A guide means 37 is disposed at a predetermined distance from the supporting member 36 in the feed direction for longitudinal feed. The guide means 37 guides the pivotal paper holding plate 34 when the holding plate 34 is raised for longitudinal feed, and functions as a supporting point on which the holding plate 34 pivots when it is raised for lateral feed. The rotatable cassettes 26 and 27 are respectively provided, at the paper feeding end thereof with which the leading edge of copy paper comes in contact, with a driving means 42 comprising a driving motor 41 for turning the rotating section 35 through 90° as well as turning the lift member 40 in order to lift up a stack of papers on the pivotal paper holding plate 34. In the driving means 42, a gear 41a is secured to the driving shaft of the driving motor 41. The gear 41a is in mesh with a group of gears 43 through which the driving force of the driving motor 41 is transmitted to a first clutch 44 and a second clutch 45. The first clutch 44 is disposed at the side of the paper feeding end of the rotating section 35 in order to suspend and execute the transmission of the driving force utilized for turning the rotating section 35 through 90°. The first clutch 44 has a driving shaft 44a to which a pulley 46 is secured. The other side of the paper feeding end of the rotating section 35 is provided with a pulley 47, and an endless belt 48 passes around these pulley 46 and 47. The lower part of the belt 48, which passes under the pulleys 46 and 47 is provided with a moving block 50 secured to a predetermined position thereof such that the moving block 50 reciprocates as the belt 48 moves. At the substantially central part of the moving block 50 is provided a through-hole through which a guide shaft 51 passes. The guide shaft 51, by which the moving block 50 is linearly guided, is disposed between the pulleys 46 and 47 in a direction orthogonal to the feed direction. On the moving block 50 is provided a pivot pin 50a by which a holding member 52 is pivotally supported. A substantially L-shaped angle section 52a provided for the holding member 52 is attached to one corner of the rotating section 33 at which the wall portion 33a comes in contact with the wall portion 33b. As shown in Fig. 2, in the vicinity of one end of the guide shaft 51, a position detection switch 100 is provided, while a position detection switch 101 is provided in the vicinity of the other end thereof. The position detection switch 100 is switched on by a switch actuating segment 52b secured to the angle section 52a and the position detection switch 101 by an actuating segment 50b secured to the moving block 50. The second clutch 45 effects and suspends the transmission of the driving force for lifting up copy papers stacked on the rotating section 34 and the output force of the second clutch 45 is transmitted to the rotary shaft 54 via the group of gears 53. More specifically, the output force of the second clutch 45 is transmitted to the rotary shaft 54 disposed in a direction perpendicular to the driving shaft of the second clutch 45, via the group of gears 53, a worm gear 53a and a wheel gear 53b which meshes with a worm gear 53a. At the other end of the rotary shaft 54, there is secured a coupling part 55a which is one component of a first coupling 55 (coupling means). At the end of a rotary shaft 56 rotatably supported at the main body of the copying machine 1 is secured a coupling part 55b which is the other component of the first coupling 55. A gear 56b secured to the rotary shaft 56 is in mesh with a gear 57a secured to a rotary shaft 57. Likewise, the rotary shaft 57 juxtaposed with the rotary shaft 56 is pivotally supported by the main body of the copying machine 1. At the end of the rotary shaft 57, a coupling part 58b which is one component of a second coupling 58 (coupling means) is secured. A coupling part 58a, which is the other component of the second coupling 58, is secured to one end of the lift-up shaft 60 (rotary lift-up member). The lift-up shaft 60 is in parallel with the rotary shaft 54 and the substantially central part thereof is provided with a lift member 40 secured thereto. This lift member 40 is pivoted by the rotation of the lift-up shaft 60, thereby raising the paper feeding end of the pivotal paper holding plate 34. The other end of the lift-up shaft 60 is just pivotally held without any member connected thereto. The lift-up shaft 60 is provided with a switch actuating segment 60a (shown in Fig. 2) secured thereto and there is disposed a lift detection switch 61 in the vicinity of the switch actuating segment 60a, the lift detection switch 61 being switched ON and OFF by the pivot of the switch actuating segment 60a. Whether the pivotal paper holding plate 34 is raised or not is detected by the turning of the lift detection switch 61. A driving force is transmitted to the lift member 40 by means of the group of gears 53, the rotary shaft 54, the first coupling 55, the rotary shafts 56 and 57, the second coupling 58 and the lift-up shaft 60. The coupling means, by which the driving force is cut off in cooperation with the removal of the rotatable cassette 26 or 27, is made up of the first coupling 55 and the second coupling 58. The lift-up shaft 60 functions as the rotary lift-up member for releasing the pivotal paper holding plate 34 from its raised condition. More concretely, the lift-up shaft 60 is let down by the disengagement of the coupling means and the lift member 40 secured to the lift-up shaft 60 gets free and pivots downward because of its own weight, thereby releasing the holding plate 34 from its raised condition. Each of the coupling parts 55b and 58b is resiliently supported by a spring coil (not shown) in the axial direction. Therefore, a shock generated at the time of the engagement of the coupling parts 55a and 55b and that of the coupling parts 58a and 58b is absorbed and the coupling condition is ensured. As shown in Fig. 4, there is provided a supporting board 63 above the paper feeding end of the rotating section 35, being secured to the main body of the copying machine 1. On the supporting board 63, there is provided a paper feed mechanism 62 for delivering copy paper to the paper feed path 22. The supporting board 63 is provided with openings 63a, 63b and 63c. The opening 63a allows a part of a pick-up roller 65 disposed in the paper feed mechanism 62 and a part of a paper feed roller 66 to respectively project downward from the supporting board 63. The opening 63b allows a part of a paper pushing back member 81 to project downward from the supporting board 63 and the opening 63c allows a part of a pressure contact releasing lever 76 to project downward from the same. In the paper feed mechanism 62, the pick-up roller 65 is positioned above the paper feeding end of the rotating section 35, and the paper feed roller 66 is juxtaposed with the pick-up roller 65, being at a predetermined distance therefrom in the feed direction. An endless belt 67 passes around each of these rollers 65 and 66 at one end, whereby the rollers 65 and 66 are rotated in the same direction. A pair of roller arms 68 stretch between a supporting shaft 65a for rotatably supporting the pick-up roller 65 and the rotary shaft 66a for transmitting the driving force to the paper feed roller 66, with these rollers 65 and 66 between. The pick-up roller 65 goes up and down as the pair of roller arms 68 rotate on the rotary shaft 66a, whereby the pick-up roller 65 comes in contact with or is separated from the copy paper. Each of the roller arms 68 is provided with a projection part 68a at one end close to the paper feed roller 66. The projection parts 68a are pressed downward by a paper feed operation angle 70 so that the roller arms 68 pivot upward. The paper feed operation angle 70 is secured to one end of a paper feed operation shaft 71 and pivots as the paper feed operation shaft 71 rotates. A solenoid connecting plate 72 is secured at the other end of the paper feed operation shaft 71. At the end of the solenoid connecting plate 72, there is formed an elongated hole with which an operation shaft 73a of a paper feed solenoid 73 is coupled. The upward/downward movements of the operation shaft 73a are converted to the rotating movement of the paper feed operation shaft 71 via the solenoid connecting plate 72. As shown in Figs. 5(a) and 5(b), a mounting board 75 is installed under the paper feed roller 66. The mounting board 75 is provided with a reversing roller 74 for conveying a copy paper in the reverse direction as it rotates in the same direction as the rotation of the paper feed roller 66. The mounting board 75 pivots upward and downward whereby the reversing roller 74 is brought in contact with or is separated from the paper feed roller 66. A rotary shaft 74a for transmitting the rotary force to the reversing roller 74 is disposed under the rotary shaft 66a of the paper feed roller 66, being in parallel with the shaft 66a. An actuating segment 76a of the substantially L-shaped pressure contact releasing lever 76 is interposed between the rotary shafts 66a and 74a. The pressure contact releasing lever 76 pivots on the shaft 76c on a vertical plane and when the lever 76 pivots downward, the reversing roller 74 is pressed by the lever 76 so as to separate from the paper feed roller 66. A connecting segment 76b of the pressure contact releasing lever 76 is connected to one end 77a of a pressure contact connecting/releasing member 77 and when the pressure contact connecting/releasing member 77 pivots on a shaft 77c (see Fig. 4), the pressure contact releasing lever 76 is rotated. The other end 77b of the pressure contact connecting/releasing member 77 is connected to a pin of an operation shaft 80a of a paper pushing back solenoid 80, and the operation shaft 80a moves forward and backward so that the pressure contact connecting/releasing member 77 is pivoted. The operation shaft 80a of the paper pushing back solenoid 80 is connected to the paper pushing back member 81 for pushing a copy paper back toward the rotating section 35. The paper pushing back member 81 pivots on the shaft 81a on a vertical plane. The shaft 81a is interposed between the pick-up roller 65 and the paper feed roller 66, being at a higher position than the position of the pin of the operation shaft 80a. When the operation shaft 80a moves backward, the paper pushing back member 81 pivots such that a copy paper (not shown) is pushed back to the rotating section 35. On the mounting board 63, a detection switch 82 is positioned at one side of the pick-up roller 65 and a paper detection switch 83 at the other side thereof. An actuating segment 82a of the detection switch 82 and an actuating segment 83a of the paper detection switch 83 respectively extend downward from the mounting board 63 passing through the opening 63a. The actuating segment 82a of the detection switch 82 is pressed by the pivotal paper holding plate 34 when the plate 34 is raised, while the actuating segment 83a of the paper detection switch 83 is pressed by the copy papers stacked on the plate 34 when the plate 34 is raised. In the above arrangement, the pivotal paper holding plate 34 is provided with an opening (not shown) at the paper stacking position for longitudinal feed. The plate 34 is provided with another opening (not shown) at the paper stacking position for lateral feed. Therefore, when no paper is placed on the pivotal paper holding plate 34, the actuating segment 83a pierces the opening so that the paper detection switch 83 is not switched ON while the detection switch 82 is switched ON. On the other hand, when papers are placed on the pivotal paper holding plate 34, the detection switch 82 and the paper detection switch 83 are both switched ON. Now, reference is made to Figs. 6(a) to 6(d) for explaining the movement of the rotating section 35 when it moves from the lateral feed position to longitudinal feed position. As shown in Fig. 6(a), when the rotating section 35 is in the lateral feed position, the wall portion 33b is in juxtaposition with the paper feeding end of the rotatable cassette 26 (or 27). In this condition, the moving block 50 and the holding member 52, which constitute the moving means, are positioned on one end of the guide shaft 51. When the driving force of the driving motor 41 is transmitted to the pulley 46 via the first clutch 44, the pulley 46 is rotated thereby rotating the belt 48. Then, the moving block 50 fixed to the belt 48 is guided by the guide shaft 51 to move to the other end of the shaft 51. As the moving block 50 linearly moves, the rotating section 35 is rotated in the direction indicated by the arrow A. Since the rotating section 35 is connected to the moving block 50 and the moving block 50 linearly moves, the center of the rotation of the rotating section 35 is moved. Such a movement is controlled by the arm 32 for pivotally supporting the rotating section 35. More specifically, the arm 32 rotates on the pivot pin 31 in the direction indicated by the arrow D, thereby ensuring the movement of the rotation of the rotating section 35. The rotation of the arm 32 in the direction indicated by the arrow D is carried out until the line X between the pivot pin 50a of the moving block 50 and the pivot pin 32a makes a right angle with the guide shaft 51. As shown in Fig. 6(c), when the angle made by the line X with the guide shaft 51 exceeds 90°, the arm 32 starts to rotate in the direction indicated by the arrow C while the rotating direction of the rotating section 35 is unchanged. Thereafter, the moving block 50 comes to the other end of the guide shaft 51 as shown in Fig. 6(d), the position detection switch 101 is switched ON by the actuating segment 50b secured to the moving block 50. The control unit of the copying machine 1 detects the operation of the position detection switch 101, and then controls the first clutch 44 to suspend the transmission of the driving force, thereby halting the movement of the moving block 50. At that time, the wall portion 33a of the rotating section 35 is turned to be in juxtaposition with the paper feeding end of the rotatable cassette 26 (or 27). The rotation of the rotating section 35 from the longitudinal feed position to the lateral feed position can be achieved by reversely rotating the driving motor 41 and carrying out the operations opposite to the foregoing procedures. When the rotating section 35 is set in the lateral feed position, the position detection switch 100 is switched ON by the switch actuating segment 52b of the holding member 52. The control unit of the copying machine 1 detects the operation of the position detection switch 100 and controls the first clutch 44 to suspend the transmission of the driving force, thereby halting the movement of the moving block 50. The following description explains the operation for raising the paper feeding end of the pivotal paper holding plate 34. With the actuation of the second clutch 45, the driving force of the driving motor 41 is transmitted through the group of gears 53; the rotary shaft 54; the first coupling 55; the rotary shaft 56; the rotary shaft 57; the second coupling 58; and the lift-up shaft 60. The rotation of the lift-up shaft 60 causes the lift member 40 to be pivoted. After pivoting upward, the lift member 40 passes through the opening 33c of the paper feed base 33 and comes in contact with the bottom face of the pivotal paper holding plate 34, thereby raising the paper feeding end of the pivotal paper holding plate 34. After the pivotal paper holding plate 34 is raised, the paper feed mechanism 62 picks up the copy paper. It is assumable that at the stage of the raising of the pivotal paper holding plate 34, the absence of copy paper may be detected by the paper detection switch 83 or a jam may occur in picking up a copy paper. In that case, the user takes out the rotatable cassette 26 or 27 from the main body of the copying machine 1. When the rotatable cassette 26 or 27 is taken out, the rotating section 35, driving motor 41, and the first and second clutches 44 and 45, which are all disposed within the cassette 26 (27), are taken out together with the cassette 26 (27), while the paper feed mechanism 62, and the rotary shafts 56 and 57 remain within the main body of the copying machine 1, as shown in Fig. 2. Thanks to the fact that the rotary shafts 56 and 57 remain within the main body, the coupling part 55a is disengaged from the coupling part 55b in the first coupling 55 and the coupling part 58a is disengaged from the coupling part 58b in the second coupling 58, whereby the transmission of the driving force of the driving motor 41 to the lift member 40 is suspended. In cooperation with the above, the lift-up shaft 60 gets free, and the lift member 40 is pivoted downward by its own weight, so that the pivotal paper holding plate 34 is released from its raised condition to be let down. With such an arrangement, even if the user is not aware the pivotal paper holding plate 34 is in its raised condition and takes out the rotatable cassette 26 or 27 from the main body of the copying machine 1, the contact of the pivotal paper holding plate 34 and the paper feed mechanism 62 can be prevented since the plate 34 is let down in cooperation with the cassette-taking-out action. As a result, damage to the contacted parts can be avoided. In the foregoing embodiment, the coupling parts 55a and 58a are disengaged from the coupling parts 55b and 58b respectively, when the rotatable cassette unit 26 or 27 is drawn 6mm from the main body for example. Fig. 2 shows a condition in which the cassette 26 or 27 is drawn 26mm from the main body and the coupling parts 55a/55b, and 58a/58b are completely disengaged. In the foregoing embodiment, the mechanism for raising/lowering the pivotal paper holding plate is adapted to a rotatable cassette, but the invention is not limited to this. For example, the mechanism may be adapted to a fixed cassette in the similar manner. The feeding device according to the present invention comprises: (1) a cassette detachable from the main body of a copying machine, comprising a pivotal paper holding plate capable of being raised; (2) a lift member which is disposed under the pivotal paper holding plate and pivots on a vertical plane so as to raise the pivotal paper holding plate; (3) a rotary lift-up member for allowing the lift member to pivot thereon, the lift member being secured to the rotary lift-up member; (4) driving means for transmitting a driving force to the rotary lift-up member; and (5) coupling means interposed in the driving means, for effecting and suspending the transmission of the driving force for rotating the rotary lift-up member. With such an arrangement, even if the cassette is taken out from the main body of the copying machine for supplying copy paper or settling a paper jam when the cassette is in a raised condition, the paper feeding end of the pivotal paper holding plate can be prevented from touching with the feeding mechanism provided within the main body of the copying machine so that damage to the contacted parts can be avoided, since the lift member is pivoted downward by its own weight in cooperation with the removal of the cassette and the pivotal paper holding plate is released from its raised condition.

Claims: A feeding device comprising a copy material feed unit (26, 27) to be mounted in and removed from an apparatus (1) to which the device is adapted, and which has a pivotal copy material holding plate (34) on which copy materials are stacked and which is capable of being raised; driving means (42, 60, 40) for transmitting a driving force for raising the pivotal copy material holding plate (34) until copy material placed thereon comes into contact with a feeding mechanism disposed within the main body of the apparatus (1); and means (55, 58) for arresting the driving force in cooperation with the removal of the copy material feed unit (26, 27) from the main body of the apparatus (1), thereby preventing the transmission of the driving force to the pivotal copy material holding plate (34) in order to release the copy material holding plate (34) from its raised condition; characterized in that said driving means (42, 60, 40) and parts (55a, 58a) of said means for arresting the driving force are provided within said removable copy material feed unit (26, 27) and that corresponding parts (55b, 58b) of said means for arresting the driving force are provided within the main body of said apparatus (1). The feeding device according to claim 1, characterized in that a lift member (40) is provided for raising the pivotal copy material holding plate (34), disposed under the pivotal copy material holding plate (34) so as to pivot on a vertical plane; a rotary lift-up member (60) is provided for allowing the lift member (40) to pivot thereon, the lift member (40) being secured to the rotary lift-up member (60); the driving means (42) are provided for transmitting the driving force to the rotary lift-up member (60); and that the means for arresting the driving force comprise coupling means (55, 56, 57, 58) interposed in the driving means (42) for effecting and suspending the transmission of the driving force for rotating the rotary lift-up member (60), wherein when the copy material feed unit (26, 27) is taken out from the main body (1), the lift member (40) pivots downward due to its own weight, thereby releasing the pivotal copy material holding plate (34) from its raised condition. The feeding device according to claim 2, wherein the copy material feed unit (26, 27) includes copy material orientation changing means (35) which is rotatable to at least two feed positions, i.e., a longitudinal feed position from which copy material longitudinally oriented with respect to a feed direction is fed and a lateral feed position from which copy material laterally oriented with respect to the feed direction is fed. The feeding device according to claim 3, wherein the copy material orientation changing means (35) includes at least two copy material stacking positions, i.e., a longitudinal copy material stacking position on which copy materials are stacked for longitudinal feed and a lateral copy material stacking position on which copy materials are stacked for lateral feed. The feeding device according to claim 4, wherein the copy material orientation changing means (35) has a two-sheet structure consisting of a copy material feed base (33) and the pivotal copy material holding plate (34) positioned on the copy material feed base (33), and is rotated through 90° so as to change the orientation of the copy materials stacked thereon with respect to the feed direction. The feeding device according to claim 5, further comprising guide means which includes (1) a sustaining member (34c) having a guide hole formed in a vertical direction; and (2) a guide member (36) which engages with the guide hole, such that the pivotal copy material holding plate (34) is guided by the guide means when the copy materials stacked on one of the copy material stacking positions of the pivotal copy material holding plate (34) are lifted up, and the pivotal copy material holding plate (34) pivots on the guide means when the copy materials stacked on the other copy material stacking position are lifted up. The feeding device according to claim 6, wherein the driving means (42) comprises a single driving motor (41) for driving the copy material orientation changing means so as to rotate through 90° and driving the pivotal copy material holding plate (34) so as to pivot for lifting up the copy material. The feeding device according to claim 7, wherein the driving means (42) comprises (1) a group of gears (41a, 43) for transmitting the driving force of the driving motor (41); (2) a first clutch (44) for effecting and suspending the transmission of the driving force through the group of gears (41a, 43), the driving force being utilized for rotating the copy material orientation changing means (35) through 90°; and (3) a second clutch (45) for effecting and suspending the transmission of the driving force toward the lift member (40), the driving force being utilized for lifting up the copy materials stacked on the pivotal copy material holding plate (34). The feeding device according to claim 8, wherein the driving means further comprises a rotary shaft (54) for transmitting the driving force from the second clutch (45), the rotary shaft being connected to the coupling means (55, 58). The feeding device according to claim 9, wherein the coupling means (55, 58) disposed in the main body of the apparatus (1) is connected to the group of gears (56b, 57a) which transmits the driving force from the rotary shaft (54) to the rotary lift-up member (60) so that the rotary lift-up member (60) is rotated, causing the lift member (40) to pivot. The feeding device according to claim 10, wherein one end of the rotary lift-up member (60) is secured to the coupling means (55, 58) while the other end thereof is just pivotally held without a member connected thereto and the lift member (40) is secured to the substantially central part of the rotary lift-up member (60), so that the feeding end of the pivotal copy material holding member (34) is raised by the lift member (40) when it pivots upward in cooperation with the rotation of the rotary lift-up member (60) while the pivotal copy material holding member (34) is released from its raised condition when the rotary lift-up member (60) is disengaged from the coupling means (55, 58), causing the lift member (40) to pivot downward by its own weight. The feeding device according to claim 1 or 2, wherein the copy material may be a copy paper used for a copying machine and laser printer, or a film used for an overhead projector. The feeding device according to claim 1 or 2, wherein the copy material feed unit (26, 27) is a cassette for feeding copy material whose orientation with respect to the feed direction is not changed.

Inventors: IWAMOTO KENICHI, OKITSU MOTOAKI, SUGIMOTO YUJI, IWAMOTO, KENICHI, OKITSU, MOTOAKI, SUGIMOTO, YUJI
Applicants: SHARP KK, SHARP KABUSHIKI KAISHA
Application year: 1990
Main classification: B65H1
IPC codes: B65H1, G03G15