EP3489022B1 - Device for printing on mail items fed individually to a printing unit - Google Patents

Description

The invention relates to a device for printing from a printing unit of a franking machine, individually supplied, on at least one of the flat sides of the printing unit, driven by friction, passing flat items of mail such as envelopes, mailing bags, envelopes, cards, printed products or the like, guided in the conveying direction F on one side edge. , consisting of a conveying device which grips the mail items at a front end in conveying direction F and which forms a conveying plane of a conveying gap / channel of the conveying device with a guide plate located on the underside of the printing unit and a conveying unit opposite the guide plate.
The EP 1 183 154 B1 describes a franking machine with at least one print head of a printing unit for printing flat mail items that can be inserted or passed through, such as closed envelopes and postcards, which has a guide part protruding around the print head and opposite its mouth plane, one with the mailing objects between it and opposite one, around a guide part across the conveying direction arranged axes rotating conveyor rollers is assigned to a conveyor device transporting the items to be shipped, the conveyor device having two drive-connected ones which form a conveyor path with the guide part Has drive rollers which, viewed in the conveying direction, are arranged in front of and behind the print head and opposite one another against a drive roller, respectively. a shipping object detected in between is provided which exerts a pressure, reversible counter-pressure roller. Such conveying devices require a high level of construction precision and precise coordination of the conveying rollers and the drive elements with one another, with the drive friction being interrupted between the conveying rollers, so that irregularities in the position and stability of the shipping objects can arise, which lead to imprecise printed images and impair control.

A corresponding device for printing mail items according to the preamble of claim 1 is in the US2009 / 159405 A1 disclosed.

The problem addressed by the present invention was to create a device for printing individually supplied mail items from a printing unit of a franking machine, which is characterized by a simple structure for reliable operation with tried and tested machine elements and components and is user-friendly and service-friendly.
According to the invention, the object is achieved according to claim 1.
Of course, the device is suitable for the arrangement of further traction means rotating in parallel.

It is important for a reliable transport of the packages if the upper strand, respectively. the upper run of the traction means and the opposite guide plate form a conveyor gap / channel in which the supplied mail items are guided.

It is advantageous if the upper run of the traction means, which interacts with the guide plate, forms a section that rises (slightly) in the conveying direction F and opens into a conveying gap / channel which is used to precisely guide the transported mail items.

The rollers of the conveyor system, each assigned to a run, are expediently mounted on the free end of a lever arm of the pivotable double lever and thus determine the position of the run of the traction means.

The lever arms of a double lever are preferably connected to one another forming an acute angle, at right angles or differently therefrom, so that an optimal arrangement and function is created between the strands.

In terms of economical production and spatial positioning, it proves to be simple if the lever arms are of the same length.

In order to tension the traction means in the conveyor system, in particular its strands, it is advantageous if the rollers are jointly and evenly applied to the inside of a strand by means of spring force.

For this purpose, the traction means have an adapted to the running grooves of the pulleys, a solid profile with a round cross-section made of an elastic material such as rubber or a rubber mixture that is suitable for tensioning.

As a result, the strands of the traction means can be kept under tensile stress in the inoperative position and during operation when the shipping items are passing through.

The rollers supporting the upper run form a conveying plane which is parallel to the conveying plane and which can be adapted to the thickness of the mail items passing through in order to change the conveying gap / channel.

For this purpose, the cross-sectional height of the conveying gap / channel can be determined automatically by the thickness of a mail item supplied under the action of a spring force on the double lever.

In order to protect the conveyor mechanism and the transported mail items, the traction means of the conveyor device are advantageously under tension under constant spring force, both in the operating and in the inoperative position of the conveyor device.

To create a transition area from the transfer table into the conveyor gap / channel that is gentle on the mail items, the conveying circumferential area can be arranged on the front rollers in the conveying direction above the conveying circumferential area of the upstream deflecting rollers, so that the mail items continuously run onto the front section of the upper Trums can be done.

The deflection rollers are preferably on the axes forming the machine frame mounted parallel shafts arranged transversely to the conveying direction F, at least one shaft being driven according to the transport speed of the mail items.

An additional special meaning for a reliable functioning of the device consists in that the double levers which are pivotable in pairs between the shafts of the deflecting rollers, on transversely to the conveying direction F and parallel to each other, are pivotable to the traction means respectively. whose strands are stored assigned, whereby no additional space is required.

For this purpose, the transverse rods can be arranged or respectively in a plane determined by the shafts of the pulleys of the traction means. be fastened in the machine frame.

In order to optimize the available space, the lever arms of a double lever in the inoperative position can be distributed approximately symmetrically (evenly) on the plane defined by the crossbars, so that the lever arms of the double lever with the plane formed by the crossbars limit an approximately equal angle up and down , whereby an approximately even deflection / lifting of the strand up or down takes place when the mail pieces pass through.

It turns out to be a simple design if the springs, for example tension springs, exerting a uniform force on the double levers are connected to a lever arm of the double lever on the one hand and to a fastening element arranged approximately in the plane of the crossbars on the other.

To support the pull-in effect on the shipping items is the traction means sections Two upper strands are each assigned a freely rotatable friction wheel, which is directed from above onto the mail items fed to the traction element sections and acts to stabilize regular transport of the mail items.

For this purpose, the friction wheels can be set and adjusted in the conveying direction F behind the end edge of the transfer table above the traction element section for optimal detection of the mail items.

For an optimal distribution of the mail items on the printing unit, this can be arranged with the printing head between two pairs of rollers above the conveyor unit.

To minimize the friction of the mail items on the underside of the guide plate, the upper run of the traction means in the conveying direction F parallel beads, respectively. channel-like depressions in the guide plate that have a slight deformation, respectively. broader coverage of the shipping items on the facing surface of the traction means.

A further reduction in the friction on the underside of the guide plate can be achieved if support strips running parallel on both sides of the beads are attached to the underside of the guide plate.

In the case of a device with an upstream transfer table on which the mail items are fed to a printing unit for printing at intervals or partial intervals, the transfer table that ends over the circumference of the deflection rollers is advantageously formed by recesses into which the traction means with their front ends for trouble-free Intervention.

Fig. 1

einen Längsschnitt durch die erfindungsgemässe Einrichtung resp. durch ein Druckwerk einer Frankiermaschine bei der Zuführung eines schematisch dargestellten Briefumschlags als Versandstück.

Fig. 2

eine Darstellung der in Fig. 1 veranschaulichten Einrichtung beim Bedrucken/Frankieren des Briefumschlags,

Fig. 3

eine Darstellung der in den Fig. 1 und 2 gezeigten Einrichtung beim Bedrucken/Frankieren eines dünnen Versandstücks und

Fig. 4

einen Querschnitt durch die Einrichtung gemäss Linie A - A in Fig. 3.

The invention is described below with reference to the cited resp. the citing prior art and the drawing, to which reference is made with regard to all details not mentioned in more detail in the description, explained using an exemplary embodiment. In the drawing show:

Fig. 1

a longitudinal section through the inventive device, respectively. by a printing unit of a franking machine when a schematically illustrated envelope is supplied as a mail item.

Fig. 2

a representation of the in Fig. 1 illustrated facility for printing / franking the envelope,

Fig. 3

a representation of the Fig. 1 and 2 device shown when printing / franking a thin mailpiece and

Fig. 4

a cross section through the device according to line A - A in Fig. 3 .

The Figs. 1 to 4 show a device 1 for printing on a printing unit 2 of a franking machine 3 individually supplied mail items 4 such as envelopes, mailing bags, sleeves, printed products or the like. Fig. 1 shows a postage meter machine 3 immediately when a relatively thick mailing item 4 is being fed into the printing unit 2. The mailing items 4 are individually by hand or from an upstream separating device (not shown) for stacked mail items 4 to a printing unit 2 of the franking machine 3 by means of a transport device via a transfer table 5 in the conveying direction F.
As the figures show, a guide plate 6 is arranged on the underside of the printing unit 2 at least approximately over the width of the supplied mail items 4, which forms a horizontal, overhead transport plane 7 for the fed mail items 4 and below a print head 8 of the printing unit 2 Has opening 9 for printing the mail items 4. The guide plate 9 forms the horizontal transport plane 7, along which the mail items 4 arriving at the conveyor end of the transfer table 5 are picked up by a conveyor 11 of a conveyor device 12 at the front end 13 and transported by this under the printing unit 2 and the printing unit 2 continues along the transport plane leave. The conveyor 11 and the conveyor level 7 are at a standstill, respectively. in the inoperative position of the printing unit 2 against one another; When the mail items 4 pass through, a part of the conveyor mechanism 11 that is effective for conveying is lifted downwards from the guide plate 9 or the conveying plane 7, corresponding to the thickness of the mail item 4. Guide plate 9 and conveyor 11 form a conveyor gap, respectively. Conveying channel 14 which extends at least approximately over the width of the conveying plane 7 and is delimited by a lateral guide 15 for positioning a mail item 4.
In order to promote the transport or conveying performance by traction means 18, 19 and to reduce the friction of the shipping items 4 on the guide surface of the guide plate 6, the latter points in the effective area of the conveying strand 24, 25 of the traction means 18, 19 in the conveying direction F of the traction means 18, 19 assigned to them Corrugations 47 and channel-shaped depressions, in which the shipping items 4 are deformed by the traction means 18, 19 to the semicircular surface of the latter - not in contact with this - in order to optimally use the conveying effect of the upper run 24 of the traction means 18, 19 and to be able to largely exclude the friction of the mail items 4 on the large-area guide plate 6.
On both sides next to the beads 47 and running parallel to them, in order to further reduce the friction on the underside of the guide plate 6, projecting support strips 48 are attached to the latter, which hold the shipping items 4 at a small distance from the guide surface of the guide plate 6, the traction means 18, 19 on the inside, for example, are assigned one support strips 48, each on the outside with two parallel support strips.

Both the printing unit 2 and the conveying device 12 are firmly connected to a machine frame 16 of the device 1.
The conveying mechanism 11 consists of at least two traction means 18, 19, which are spaced apart from one another around common horizontal axes on deflection roller pairs 16, 17 laterally spaced in the conveying direction F, and which each form a strand 24, 25 along the conveying plane 7 and opposite it. The traction means 18, 19 are preferably designed with a circular full cross-section and consist of an elastic material such as rubber or a rubber mixture, which give off a favorable coefficient of friction.
Accordingly, the deflection rollers of the deflection roller pairs 16, 17 have a groove or running groove on the circumference, which corresponds to the cross section of a circumferential traction means 18, 19.
The strand 24, 25 of the traction means 18, 19, respectively. the upper 24 and the lower Trum 25 are between the pulleys on running or. Support rollers 20, 21 supported, each of which is freely rotatably mounted on the free ends of a pivotable double lever 26 formed from angled connected lever arms 27, 28, so that the upper run 24 with the lower run 25 jointly follow the thickness of a mailing item 4 Can be adjusted / moved down or up.
Both in the inoperative position and in the operating position when shipping items 4 pass through, the rollers 20, 21 of the conveyor 11 support / guide the strands 24, 25 evenly on a transport or Guide plane 7 parallel conveying section 22 of the upper run 24 and the ineffective lower run 25 of the traction means 18, 19.
The running / supporting rollers 20 acting in a supporting manner on the inside on the conveying section 22 of the upper run 24 are achieved by a spring force exerted on the double lever 26, for example by a spring force Fig. 1 and 2 tension spring 23 shown.
The upper rollers 20 hold the upper run 24 in the area of the conveyor section 22 against the guide plate 6 below the printing unit 2, so that the conveyor sections 44 of the run 24 are approximately in contact with the guide plate 2 in the inoperative position.
As a result, in the entrance area of the conveyor gap / channel 14, a channel inlet opening that tapers in the conveying direction F of the mail items 4 or a feed gap 29 is formed, the cross-sectional height of which is determined / opened by the thickness of a fed mail item 4 against the action of the force of the spring 23 .
At the same time, the printing unit 2 is in the inoperative position - see Fig. 1 - The respective lower run 25 of the traction means 18, 19 in a position initiated by the assumed position of the double lever 26 (upper end position), in which the upper and lower strands 24, 25 of the traction means 18, 19 are not stretched over their entire length by the traction means sections 31 formed at the ends of the strands 24, 25, but the channel inlet opening 29 is only accessible through a mail item 4 arriving from the transfer table 5 . The cross-sectional height of the conveyor gap / channel 14 is determined under the action of the spring force from the spring 23 on the double lever 26 by the thickness of the mail items 4 supplied.
The device is characterized, among other things, by the fact that, with the adjustable strands 24, 25 of the traction means 18, 19, a permanent tension of the latter is maintained both outside of operation and during operation of the present conveyor system 11.
The entrance area in front of the conveyor gap / channel 14, viewed in the conveying direction F, has a roller 20 standing higher than the front deflection roller 16 and subsequent rollers 20, so that, viewed in the conveying direction F, a rising and conveying traction element 31 formed by the upper run arises, its rise changes by the different thickness mail pieces 4 in the cycle of the feed.
Thicker or thinner mail pieces 4 supplied in a clocked manner change the inclination of the rise in the traction element sections 31 acting in the supply area and the cross-sectional height of the conveyor gap, respectively. Conveyor channel 14 respectively. the location of the strand 24.25.
The length of the conveyor gap / channel 14 depends on the thickness of a mail item 4.
The traction means 18, 19 are kept under constant tension by the double levers 26, which each form a traction mechanism, permanently loaded with spring force, and the running / support rollers 20, 21 on the inside of the strands 24, 25 of a traction means 18, 19.

The conveyor 11 (tensioning mechanism) formed from common axes 32, 33 for the deflection rollers 16, 17 of the traction means 18, 19, aligned transversely to the direction of movement F of the mail items 4, is in the machine frame 10 of the franking machine 3, for example in a lower part of a machine stand, below of the printing unit 2 arranged.
The deflection rollers 16, 17 are attached to the driven shafts 34, 35 which form the axes 32, 33 and are mounted in the machine frame 10 and by which a shaft 34 and 35 is driven.
The double levers 26 are of between the axes 32, 33, respectively. Shafts 34, 35 of the pulleys 16, 17 and at intervals from one another, parallel bearing forming cross bars 36 pivotable in pairs and the traction means 18, 19, respectively. their strands 24, 25 stored assigned.
The transverse rods 36 are preferably arranged or respectively in a (horizontal) plane formed by the axes 32, 33 of the deflecting rollers 16, 17 of the traction means 18, 19. attached in the machine frame 10.
The lever arms 27, 28 of equal length, which each make up a double lever 26, are according to FIGS Figs. 1 to 3 connected at an angle of about 90 °.
In the inoperative position, in which the conveying strand 24 approaches the guide plate 6, the lever arms 27, 28 of a pivotable double lever 26 are distributed approximately symmetrically on the plane of the transverse rods 36 and change the position of a mail item 4 transported through the printing unit 2 due to its thickness acting on the upper run 24 as in Fig. 2 shown.
The springs 23 exerting a spring force are connected at one end to an end facing the double lever 26 with one of the lever arms 27, 28 of the double lever 26 and at the opposite end at an end in about the plane of the cross bars 36 arranged fastening element 37 clamped.
The traction element sections 31 are each in the area of the intake sections 30 of the upper strand 24 a friction wheel forming an intake gap 39 with the strand 24, respectively. Retraction wheel 38 assigned, which is acted upon by a spring force.
A mail item 4 arriving at the intake section 30 is initially received at the front edge 40 in the intake gap 39 formed by the intake sections 30 and friction wheels 38 and transported further by this unit, with the friction wheels 38 being freely rotatable or like the speed of the traction means 18, 19 can be driven and are pressed by springs 41 onto the mail items 4 on the intake section 30. For this purpose, the friction wheels 38 are fastened to a common shaft 42, which is positioned transversely to the conveying direction F and which is pivotably arranged on levers 43 loaded by springs 41.
The transfer table 5, which ends approximately over the circumference of the deflection roller pair 16 in the conveying direction F, is formed by recesses 44 assigned to the traction means 18, 19, so that a gently rising angle for the transported mail items 4 is created at the transition point between the transfer table 5 and the intake gap 39.
The same constructional measure is provided at the transition to the delivery 45 behind the printing unit 2, where a guide element 46 provided with slot-like recesses 44 and an ejection roller 49 driven about an axis transversely to the conveying direction F removes the printed mail items 4 from the traction means 18, 19 and continues.

Claims (13)

1. Device (1) for printing flat postal items (4), such as envelopes, padded envelopes, sleeves, cards, printed products or the like, fed one at a time to a printing unit (2) of a franking machine (3), passing through the printing unit (2) on at least one side in a frictionally driven manner and guided at one side edge in the conveying direction (F), consisting of a conveying device (12) gripping the postal items (4) at a front end in the conveying direction (F) and forming a conveying plane (7) of a conveying gap/channel (14) of the conveying device (12) by way of a guide plate (6) arranged on the underside of the printing unit (2) and a conveying unit (11) disposed opposite the guide plate (6), wherein the conveying unit (11) has at [east two endless traction means (18, 19) disposed at a distance alongside one another as viewed in the conveying direction (F) of the postal items (4) and each circulating about a common axis on deflecting rollers (16, 17), the tight side (24) of the traction means directed towards the guide plate (6) and the slack side (25) of the traction means being guided on rollers (20, 21) mounted in a freely rotatable manner in opposing pairs at pivotable ends of one of a plurality of double levers (26) of the conveying unit (11) formed of angled lever arms (27, 28) and associated with the tight side (24) or the slack side (25) of the traction means (18, 19), and supported on the inner faces of the sides (24, 25) by means of spring force acting on the double levers (26) and wherein the rollers (20) supporting the tight side (24) form a transport plane parallel to the conveying plane (7) during the advance of the postal items (4).
2. Device according to claim 1, characterised in that the tight side (24) and the opposing guide plate (6) form a conveying gap/channel (14).
3. Device according to claim 1 or claim 2, characterised in that the tight sides (24) of the traction means (18, 19) forming a conveying gap/channel (14) together with the guide plate (6) have a section ascending in the conveying direction (F) and a section descending at the conveying gap/channel end.
4. Device according to one of claims 1 to 3, characterised in that the lever arms (27, 28) of a double lever (26) are connected together so as to form an acute angle, preferably approximately at a right angle.
5. Device according to one of claims 1 to 4, characterised in that the traction means (18, 19) have an approximately circular cross section and are made of an elastic material.
6. Device according to one of claims 1 to 5, characterised in that the cross-sectional height of the conveying gap (14) is determined by the thickness of a postal item (4) fed in, with a spring force acting on the double lever (26).
7. Device according to one of claims 1 to 6, characterised in that the traction means (18, 19) or the sides (24, 25) of the conveying device (12) are tensioned by the spring force both in the operative position and in the inoperative position.
8. Device according to one of claims 1 to 7, characterised in that the working circumferential region of the front rollers (20) of the conveying unit (11) in the conveying direction (F) is arranged above the working circumferential region of the upstream deflecting rollers (16) so as to form an ascending section (31) of the traction means.
9. Device according to one of claims 1 to 8, characterised in that the deflecting rollers (16, 17) are fastened to the shafts (34, 35) mounted in the machine frame (10) and forming the axes (32, 33), at least one of the shafts being driven.
10. Device according to one of claims 1 to 9, characterised in that the lever arms (27, 28) of a double lever (26) are aligned in such a manner that they are distributed approximately symmetrically relative to the plane defined by the transverse bars (36) in the inoperative position.
11. Device according to one of claims 1 to 10, characterised in that the springs (23) exerting a spring force on the double levers (26) are clamped, on the one hand, to one lever arm (27, 28) of the double lever (26) and, on the other hand, to a fastening element (37) arranged approximately in the plane of the transverse bars (36).
12. Device according to one of claims 1 to 11, characterised in that a freely rotatable friction wheel (38) acting from above on the postal items (4) fed in is associated with the sections (31) of the traction means in the region of an infeed section (30) of the tight sides (24).
13. Device according to one of claims 1 to 12, characterised in that the underside of the guide plate (6) has beads (47) extending in parallel in the conveying direction (F) and associated with the tight sides (24, 25) of the traction means (18, 19).

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