Receiver Tray for Photocopy Machines

This invention relates to electrophotography and more particularly to receiver trays for receiving and stacking photocopies delivered from a photocopy machine.

Electrophotographic processes and machines are well known and feed a succession of record members, typically paper, through a series of steps to form a visible image thereon and deliver the finished copies to a receiver tray for stacking. Substantial voltages are applied to the copies to form or transfer images thereon and frictional contact in feeding the copies through the machine can provide additional charge. When successive copies are delivered to the receiver tray for stacking these charges, together with frictional forces, can cause misstacking in the tray or paper jams in the machine.

It is accordingly the principal object of the present invention to provide an improved receiver tray for receiving and stacking photocopies which reduces misstacking and jams. Further objects include provision of a photocopy receiver tray which minimizes sliding contact of a delivered copy with the tray surface and the surface of preceding copies, which is capable of receiving and stacking at least two sizes of copies, and which provides a pocket for receiving and stacking at least one size of copy in the bottom of the tray.

According to the present invention, the improved receiver tray for photocopies delivered along a path from a photocopy machine comprises means for mounting the tray to the machine in position to receive copies, a bottom having front and rear portions with respect to said path, and means adjacent the rear of the tray for arresting the copies, the rear portion of the tray bottom being below the front portion to form a step therebetween, said rear portion together with said step and arresting means defining a pocket adapted for receiving and stacking at least one size of photocopy therein below the surface of the front portion. Preferably, the tray bottom declines toward the arresting means, and guide means are provided for the photocopies above the front edge of the tray bottom member, the guide means having an upper surface below said path and forming an acute angle therewith having its apex at the trailing edge of the surface with respect to said path, the trailing edge of the guide member projecting the leading edge of the delivered copy over and out of contact with a substantial part of the front portion of the tray bottom. Most preferably, the receiver tray is mounted to the exterior of a wall of the photocopy machine, the machine wall having therein an exit slot, and the guide means is transversely disposed in the exit slot.

In the accompanying drawings:

FIG. 1 is a schematic side view of a photocopy machine with parts broken away to illustrate the paper path;

FIG. 2 is a vertical section to enlarged scale of the exit portion of the machine of FIG. 1 having a receiver tray according to the present invention mounted thereto;

FIG. 3 is an exploded perspective view of the exit portion of the photocopy machine illustrated in FIGS. 1 and 2; and,

FIG. 4 is a perspective view of the receiver tray shown in FIG. 2.

Referring to the drawings, FIG. 1 illustrates a typical electrophotographic copy machine 10 which forms a toned image on photosensitive drum 12 by convention means (not shown) and transfers the toned image to copy paper at 14. The paper is fed along the path shown in broken lines from a paper feed tray 16 by means of feed wheels 18 to transfer station 14. The copy is then advanced to heater roll 20 which fuses the toner, and thence through exit rolls 22, 24 which feed the finished copy out of the machine through exit slot 26 in end wall 28. Typically, a substantial DC voltage is applied to the copy paper at station 14 by means of corona (not shown) to transfer the toner from the drum 12 to the copy paper. Frequently, an AC corona such as shown at 30 is thereafter applied to the copy paper to dissipate or minimize charge. After exiting from exit slot 26 the completed copies fall into receiver tray 32 as shown in FIG. 2.

The receiver tray 32 is shown in FIGS. 2 and 4 and comprises hooks 35 and 36, bottom 34 and a pair of upturned stops 38 and 40 for arresting motion of the delivered photocopies. Stops 38 and 40 are separated by slot 42 which allows the copies to be grasped for removal. Hooks 35 and 36 fit within slots 44 and 46 of machine end wall 28 and are formed as extensions of side members 48 and 50, the forward edges of which abut end wall 28. The hooks 35, 36 and the forward edges of side members 48 and 50 serve as means for removably mounting the tray to the machine in position to receive copies, and are preferably adapted as shown to dispose the tray bottom 34 at a downward tilt or decline toward stops 38, 40 to aid by gravity delivery of copies to the stops.

Tray bottom 34 comprises, with respect to the copy path shown, rear portion 52 and front portion 54, the portion 52 being below the portion 54 to form between them a step 56. Portion 52, together with step 56 and stops 38, 40 define a pocket for receiving and stacking at least one size of photocopies therein below the surface of front portion 54. Step 56 is preferably of a height of one-half inch or more sufficient to stack a substantial number of copies in the pocket.

The surface of front portion 54 is preferably polished, waxed or otherwise provided with a low friction surface and is preferably of a length at least equal to the length of portion 52. Portion 52 is sized to receive and stack the most common size of copy, for example 81/2.times.11 inches. Larger copies bridge the step 56 and rest for stacking partly over portion 54.

The bottom portions 52 and 54 can be integrally formed, or portion 54 can comprise an insert as shown fitting over a forward extension of portion 52. Step 56 can be disposed at any suitable angle but is preferably substantially perpendicular to the surface of portion 52 as shown. It preferably comprises a solid wall but may be left partly or wholly open, if desired.

To further minimize misstacking and jams, it is preferred to employ a guide member 60 (FIGS. 2 and 3) which directs the delivered copy over and out of contact with a substantial part of the front portion 54 of tray bottom 34. Guide member 60 is transversely disposed in the exit slot 26 of machine end wall 28 and over the front edge of tray bottom 34. Its upper surface is below the delivery path of the copy and forms therewith an acute angle having its apex at the trailing edge 62. Any sag in the leading edge of a photocopy being delivered by exit rolls 22, 24 will contact the smooth upper surface of member 60 and be directed to edge 62. Thereafter, the copy wll contact substantially only edge 62 to minimize friction and drag and the beam strength of the copy paper will cause it to advance well out and over tray bottom portion 54, further reducing contact and friction with the latter.

Guide member 60 can be mounted over tray bottom 34 and transversely of slot 26 in any suitable manner. If desired, it can be mounted to the tray, for example, between side walls 48, 50. As shown, it is provided with depending legs 62, 64 which are secured in abutment with machine end wall 28 below slot 26 by means of screws 66 and clamps 68. As shown, exit slot 26 has a lower inturned lip 58 on which the member 60 may rest. Such lips are sometimes provided but are not required.

As can be seen from FIG. 2, the delivered copy is advanced by rolls 22, 24 through slot 26, over edge 62, and out and over a substantial part of surface 54. When free of rolls 22, 24 the copy will contact the lower portion of surface 54 and fall by momentum and gravity into pocket 52, arresting at stops 38, 40. Frictional contact, and misstacking and jams, are minimized. The improvement is sufficient in some cases to allow discharging AC corona 30 to be omitted.

It should be understood that the foregoing description is for the purpose of illustration and that the invention includes all equivalents and modifications within the scope of the appended claims.