DD202603A5 - DEVICE FOR CREATING A RUNNING COPIER SHEET TO A CIRCULAR PHOTO DRUM - Google Patents

Abstract

The invention relates to the application of a current copy sheet to a rotating photo drum in the electrophotographic image transfer by means of toner image. The invention proposes a simplified, functionally reliable structural design for such devices, wherein along the guideway no driven conveyor rollers for the copy sheet are more necessary and also accounts for the usual baffles. The essence of the invention consists in an improved guide device, which essentially has a spaced apart from its center of gravity guide rocker 13 about an axis parallel to the axis of the photo drum 3 extending axis 17 from a basic position, which it takes under its weight to 360 Degree is freely pivotable. The guide device 13 has a hook 12 with a catch notch 15 in which the leading edge of a copy sheet 2 engages and the rocker 13 is pivoted against its weight from the basic position up to the photo drum 3 in the direction of a Ausgabeführungsvorrichtung 25,26,22 , Fig.2

Description

Device for applying a copy sheet

Field of application of the invention:

The invention relates to an apparatus for applying a current copy sheet to a rotating photo drum for ektrotrafografische image transmission.

Characteristic of the known technical solutions:

A device of this kind is known, for example, from US Pat. No. 4,218,128 . In the known device, the copy sheet from Zuführrollenpaar up to the output roller pair is held by baffles and additional Andrüclc- and guide rollers on aer desired track. The contact between the photographic drum and the copying sheet required for a perfect transfer of the image is ensured, in particular, by a pressure roller arranged behind a corona, through which the copying sheet is held in contact with the phototrund, viewed directly in the transporting direction of the copy sheet Disadvantage aer known device is that 'by the generated by the baffle encapsulation of the guideway to the outside, the device not only very expensive, but also the free insight into the Kopierblattfünrung is impossible, the out at and

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re-occurring copy sheet jams for a quick resolution of the disturbance is desired. In addition, due to the large number of driven rollers or pairs of rollers, synchronization problems occur between the guiding and driving devices ^{1 of} the copy sheet guide and the photo drum.

.Goal of

The aim of the invention is the improvement of the device mentioned above with respect to the disadvantages shown.

Explanation of the essence of the invention.

The invention has for its object to arrange for transporting the copy sheet along the guideway as little as possible driven conveying elements or conveyor rollers, without having to be taken neither with regard to the synchronization nor an inadequate contact between Kopie.rblatt and Fototromraei deficiency.

According to the invention, the object is achieved in that the guide device has a spaced from its center of gravity bearing rocker, which is free to pivot about a parallel to the axis of the photo drum axis from a basic position, which it takes under its weight, 360 ° and the one Hook with one in the basic position of the swingarm in the way of out. has the catching groove of the feed roller pair leaked leading copy sheet edge arranged catch notch. The rocker is pivoted upwards under the drive of Zuführrollenpaares by means of the supplied from this copy sheet against its weight from the basic position and thereby causes the deflection of the copy sheet and its application to the photo drum. The device according to the invention also has an output device

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rungsvorrichtung, which lifts the leading copy sheet edge at a Aushebestelle at which the rocker with the catch notch of its hook has exceeded the upper apex of its pivotal arc, from the catch notch and introduces into the roller gap of the output roller pair.

For. the Kopierblattführ.ung invention are thus along the guideway no driven conveying elements required because the leading edge of the copy sheet pivots the Fyhrungsschwinge about its axis. The radial distance of the leading copy sheet edge receiving and on the swingarm preferably elastically mounted hook from the axis of the rocker is so large that a non-contact, but narrow Vorbeischwenken the hook on the photo drum is possible. Thus, the alignment of the rocker is guaranteed to its normal position without additional facilities, the hook-carrying swing arm is either slightly longer or slightly heavier by other means - for example, thicker than the other swing arm formed. A further significant advantage of the copy sheet guide according to the invention consists in particular in that, due to the elasticity of the essentially consisting of rocker and hook guide device without additional guide devices in the region of the vertex of the guideway bulging of the copy sheet toward the photo drum and thus a very good application of the same to the Photographic drum can be achieved.

So that the rocker is not abgeschwnkt after lifting aer leading edge of the copy sheet from the catch notch into the basic position before the trailing edge of this copy sheet has passed through the Zuführrollenpaar seen in the conveying direction of the copy sheet downstream guide gap, the rocker is after the lifting of the leading copy sheet edge the catch notch in

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held a position above its normal position ** until a time after the emergence of the trailing copy sheet edge from the Zuführrollenpaar at a the exit of the trailing copy sheet edge from this scanned locking lever. Such a, the rocker in this Ziwschensteliung fixing means, however, is unnecessary if the measured along the conveying path of the copy sheet distance between the end of the guide gap and the beginning of the output guide device is greater than the copy sheet length.

The elasticity of the guide device can be achieved, for example, by an articulated attachment of the hook to the rocker. It is particularly advantageous, however, if the hook is designed as a tongue-shaped protruding from the end of the rocker arm, the free end is designed to form the catch notch. Z-färmig.

So that the rocker quickly returns to its normal position after being released by the locking lever and can not be swiveled back and forth, a separate stop or catching device for the rocker may be arranged in the region of the feed roller pair. However, it has proven to be particularly advantageous that the guide roller for the copy sheet adjoins the roller gap of the Zuführrollenpaares at the output and the upper boundary plate of the guide gap is formed as a catch plate, from the free edge of the hook of the spring arm of the rocker, the Swinging to its resilient deceleration with the hook on the Begrenzunasplatte meets on slips until alignment of the catch notch formed in the hook on the mouth of the guide gap.

The lifting of the leading edge of the copy sheet from the hook of the Schwinae at the end of Führungsunasbahn sucat

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by the output guide device, which preferably has a lifting lever which is pivotable about a pivot axis between the photo drum and the oscillating axis parallel spaced therefrom against the force of a return spring pivotally from the upper vertex of its pivoting arc rocker by means of a stop, of which Lift lever on arrival of the leading copy sheet edge on the. Bearing derates and lifting the leading copy sheet edge under the force of the spring up to a position in which the leading copy sheet edge is aligned with the roller gap of the output roller pair.

As a rule, no driven roller or roller is required for the copy sheet guiding device according to the invention in the area of the delivery guide, by which the copy sheet is conveyed from the guide track to the delivery roller pair. In some cases, however, it may be advantageous for the delivery guide device to have a having additional drive roller, to which the excavated paper sheet can be applied by means of the release lever.

Embodiment:

The invention will be explained with reference to a preferred embodiment, which is apparent from the drawing. In the drawing shows:

1 is a schematic representation of the copy sheet guide,

2 shows a schematic representation of the co-

Pierblattführungsvorrichtung, wherein the rocker its basic position for receiving a by a Zuführrollenpaar ZUG ..

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leads copy-book,

3 shows a schematic representation of the copying

leaf guide device, wherein the rocker assumes the position in which the leading edge of the copy sheet with the hook attached to the rocker out of engagement and is conveyed away in the direction: to the output roller pair.

From Fig. 1 is schematically .die guideway 1 of a copy sheet 2 can be seen, which is brought to the top transferring a toner images to a photo drum 3, that in area 4 of a - not shown here - corona flat contact between the photo drum 3 and copy sheet comes about , As a result, among other things, the quality of the transferring toner image is promoted.

As can be seen from Fig. 2, the copy sheet 2 taken from a copy sheet cassette not shown passes through a driven feed roller pair 5 and through an adjoining guide gap formed between a restriction plate 6 and a lower guide plate 7 into the guide path provided for the transfer of the toner image 1 (Fig. 1).

The Zuführrollenpaar 5 facing ends S of the boundary plate 6 and the guide plate 7 sind.msulförmig bent so that the leading edge of a fluttering copy sheet 2 is captured and threaded with certainty in the guide gap.

The guide plate 7 consists of a boundary plate 6 parallel to the extending portion 9 and a step-shaped angled away from the limiting plate 6 and then according to aer guideway 1 arched out

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formed deflection part 10, which ends at a small distance from the photo drum 3 aer .

The .Begrenzungsplatte 6 is formed except for the end 8 as a flat plate, the photo drum 3 facing end protrudes beyond the step in the guide plate 7 and serves as a stop surface 11 for a hook 12, as a from the end of the heavier swing arm 13a of a rocker 13 tab-shaped radially from the edge of the swing arm 13a in the counterclockwise direction approximately tangentially projecting spring arm 14 is formed and at its free, approximately Z-shaped end a catch groove 15 is bent. The seen from Zuführrollenpaar 5 convex bend 16 of the free end of the spring arm 14 cooperates with the stop surface 11 as a stop. The catch notch 15 is seen from Zuführrollenpaer 5 as a concave curvature formed. The vertex oer catch groove 15 is in the amount of the guide gap between. The length of the swing arm 13a is so -emeasured that a frictionless movement between hooks 12 and catch groove 15 on the one hand and the guide plate 7 and the deflection part 10 on the other hand is possible.

The rocker 13 is mounted at the point 17. Due aer high elasticity of the system of rocker arm 13 and spring arm 14, the movement path of the free end of the Federamres 14 of the limits of the length of the swing arm 13a circular path may vary. This is a simple way of a flat contact between the photo drum. 3 and copy sheet 2 in the region of the corona 18 allows.

At a point 19 within the circumscribed by the rocker 13 circle, above the horizontal .Durch- '

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the same is here, for example, attached to the rear wall of the corona housing, a plate 20, at the upper free end of a spring 21 is mounted, which is fastened with its other end to a lever 22.

The lifting lever 22 is articulated at its one end to the plate 20 at the point 23. Be .anderes end, which accounts for about one third of its total length is bent counterclockwise at an obtuse IVinkel r ^ u of about 150 °. The end of the bent part of the lifting lever 22 protrudes in the starting position, the same (Fig. 2) radially beyond the circular path described by the swing arm 13a. An essential feature of the copy sheet guide according to the invention is, in particular, that the rocker 13 and lever 22 in decorum arranged bearings 17 and 23, so that an intersection of the described by rocker arm 13a and lever 22 is achieved, which is about in the amount of the intersection of a passing through the bearing 17 and 30 straight line with the circle of the rocker 13 is located. Slightly offset from the apex of the upper half of the guide track 1 towards a discharge roller pair 24, a drive roller 25 is disposed so as to engage; it comes in contact with the copy sheet 2 running along the tangent line through the gap of the output roller pair 24 to the guide track 1.

The free end of the lifting lever 22 extends almost to this tangent, so that a voltage applied to the drive roller 25 Kopierbiatt 2 also abuts the upper end edge of the free end of the lever 22 and is supported by this, so that reliably kinking the Kopierbiattes. 2 in the direction (arrow 36) of the circle described by the swing arm 13a is avoided. The lifting lever 22 takes a through a stop 28th

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defined position between the drive roller 25 and a guide plate 26, the guide surface 27 lies in the plane of said tangent.

The axes of the rocker 13, the lifting lever 22, the Zuführrollenpaares 5, the photo drum 3, the drive roller 25 and the output roller pair 24 are parallel to each other. ,

The photo drum 3 facing the end of Leitpiatte 25 is bent so that even below the tangent to the guide plate 26 bumping copy sheets 2 are directed to the guide surface 27 out »

Arn free end, namely, on, the leading edge of the swing arm 13a, a, in the direction parallel to the axis of the rocker 13 projecting driving pin 29 is arranged. By the driving pin 29, the lifting lever 22 is against the spring force of the spring 21 taken at a rotation of the rocker 13 .. At the point P. (Fig. 3), that is the intersection of durch.die leading edge of the swing arm 13a and through the circuit pin 21 described with the circle described by the free end of the lever 22, which is pivoted about La.ger 23 in the clockwise direction, swing arm 13a and lever 22 go out of engagement, so that the lever 22 under the force of the spring 21 in the position given back by the stop 28 snaps back.

Below the guide plate 26, but outside the circle described by the swing arm 13a, a locking lever 31 is pivotally suspended at the point 30, which is held in the rest position under the force of the spring 32 in the apparent from Fig. 2 position. The locking lever 31 has on its side facing the photo drum 3 a locking lug

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33, which is formed above the v, raagefechten diameter of the circle described by the swing arm 13 a on the locking lever in the form of a protruding teeth. By this locking lug 33, in the position shown in FIG. 3 (blocking position) of the locking lever 31 of the swing arm 13 a can be held. The blocking position of the locking lever 31 is achieved by a clockwise pivoting thereof about the axis 30 '. The pivoting takes place against the spring force of the spring 32nd

The locking lever 31 penetrates in the initial position (Fig. 2) with its free end the Begrenzunasplatte 6 and the guide plate 1, which are slotted to the point 34 accordingly. - "^:;

In the following the operation of the device according to the invention is described:

The copy sheet 2 is inserted by the Zuführrollenpaar 5 in the direction of arrow 35 in the guideway 1 and passes after leaving the Zuführrollenpaares 5 in the limited by the limiting plate 6 and the guide plate Füh'rungsspalt. Upon the entry of the leading edge of the copy sheet 2 in the guide gap, the free end of the locking lever 31 is taken. At the point where the circle circumscribed by the free end of the locking lever intersects the guide track 1, the free, rounded end of the locking lever 31 slides on the surface of the copy sheet facing the bearing 17 of the rocker 13 in this position (position - see FIG. 3) ), the locking lever 31 is held with its free end on the copy sheet 2 against the force of the spring 32 while sliding until released after passing the trailing edge of the copy sheet 2 of the locking lever 31 and allows it to snap back into the starting position

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The leading edge of the copy sheet 2 engages after leaving the guide gap in the catch notch 15 and moves via the spring arm 14 the swing arm 13a in a clockwise direction along the guide track 1. The copy sheet 2 is bent in this movement process the resulting weight of the swing arm 13a and radially from externally supported on the deflecting part 10 of the guide plate 7. In the area of the corona 18 passes the copy sheet. 2 under the resultant weight of the swinging arm 13a into surface contact with the photo drum 3.

A short time after the top of the vertex of the upper half of the guideway 1, the driving pin 29 engages with the lever 22, which is thereby pivoted against the force of the spring 21 'about the axis 23 in a clockwise direction, as soon as the leading end provided with the Mitnehraerstift 29 Edge of the swing arm 13 a-the point P has passed through (Fig. 3), the hitherto entrained lifting lever 22 is released and zurückknwnkt under the force of the spring 21 in the position shown in FIG. 2. Characterized the previously entrained in the catch notch 15 leading edge of the copy sheet 2 is ejected to the concerns of the copy sheet at the bottom of the driven roller 25 from aer catching notch 15 and beyond the free end of the Aushebehebels 22 and the guide surface 27 toward the output roller pair 25 directed. The advancement of the Kopierblsttes 2 takes place during this movement section still by the Zuführrollenppar. 5

The swinging arm 13a is, as long as the trailing edge of the copy sheet has not yet passed the guide gap, held by the locking lug 33 formed in the locking lever 31 (Fig. 3). However, as soon as the trailing edge of the copy sheet 2 has released the free end of the blocking lever 31 and the same has returned to its starting position by the spring 32, the oscillation passes.

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arm 13a with the latch 33 out of engagement. As a result, the - here longer - swing arm 13a falls down until it meets with the end of his spring arm 14 on the boundary plate 6 and slips over the free edge. Then, when the over its basic position slightly beyond swinging the swing arm 13a swinging back under the force of gravity, it fails with the Äbbiegung 16 of its Reder arm 14 against the stop surface 11 so that it is stopped in its home position and for the occurrence of the leading edge of the next copy sheet in the Catch notch 15 ready again (Fig. 2).

As soon as the trailing edge of the copy sheet 2 has left the guide gap, the copy sheet is transported exclusively: by the drive roller 25 and by the output roller pair 24.

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Claims (6)

2399 5 3 6 Claim of invention: Apparatus for applying a running copy sheet (2) to a revolving photoconductor drum (3), comprising a driven feed roller pair (5) and a driven output roller pair (24) disposed above it, on the side of the photo drum (3) at the direction of movement thereof directed upward, at a distance from the photo drum (3) are arranged, and with a guide device, through the copy sheet (2) along a guide track (1) between the feed roller pair (5) and the output roller pair (24) of the photo drum (3) can be fed laterally from below and in an arc upwards in the direction opposite to the feed direction (arrow 35) to the output roller pair (24) and in the area (4) of the vertex of the guide track (1) laterally to the photo drum (3) is settable, characterized in that the guide device is mounted at a distance from its center of gravity guide rocker (13) about a parallel to the axis the photo drum (3) extending axis (17) from a basic position, which occupies it under its weight, 360 is freely pivotable and a hook (12) with a in the normal position of the rocker (15) in the way out of the roller gap Zuführrolienpaares (5) leaked leading copy.blattblatt arranged catch notch (15), so that the rocker (13) under the drive of Zuführrolienpaares (5) by means of the supplied from this copy sheet (2) against its weight from the basic position upwards pivoted and thereby causes the deflection of the 'copy sheet (2) and its application to the photo drum (3), and a leading copy sheet edge at a Aushebestelle (.P), - 14 - at which the rocker (Ιό) with its catch notch (12) has passed the top, vertex of its pivoting arc, discharging device (15) lifting out the catching groove (15) and feeding into the roller nip of the delivery roller pair (24) ( 25, 26, 22). 2. Device according to item 1, characterized in that the rocker (13) after lifting the leading copy sheet edge out of the catch notch (15) in a position above its basic position until after the - trailing copy sheet edge from the Zuführrollenpaar (5) is held on a, the exit of the trailing copy sheet edge scanning locking lever (3.1). 5. Device according to item 1 or .2, ..gekennzeichnet characterized in that the hook (12) as laschenf from the end of the heavier Schvvingarmes (13a) of the rocker örnrig projecting spring arm (14) is formed, the free end to form the catch notch approximately Z-shaped is förrnig. 4. The device according to item 3, characterized in that the same to the Roilenspalt Zuführrollenpaares (5) at the output of a guide gap for 'the copy sheet (Z) and the upper boundary plate (5) of the guide gap is designed as a catch plate, from the free Edge (abutment surface 11) of the hooks (12) of the spring arm (14) of the rocker (13), which strikes when swinging down to its resilient deceleration with the hook (12) on the boundary plate (6) until the orientation of the hook (12 ) formed catch notch (15) slips on the mouth of the guide gap. 5. Device according to one of the items 1 to 4, characterized in that the output guide device (25, 26, 22) has a Aushebehebel (22), which is an intermediate of - 15 - 239953 6 ί-ototrorarael (3) and the Schvvingenachse (17) parallel spaced at this axis (23) against the force of a return spring (21) pivotable ah of the upper apex of its pivotal curve swinging rocker (13) by means of a stop (.Mitnahmestift 29 ) is entrained, from which the lifting lever (22) at the arrival of the leading copy sheet edge at the Aushebestelle (P) derived and pushes the leading copy sheet edge under the force of the spring (21) up to a position in which the leading copy sheet edge on the Roller gap of the output roller pair (24) is aligned. 6. The device according to item 5, characterized in that the output guide device (25, 26, 22) has an additional drive roller (25) to which the excavated copy sheet (2) by means of the release lever (22) can be applied. - For this 2 sheets drawings - - 16 -