GB2101087A - Wire dispensing apparatus - Google Patents

Abstract

Wire dispensing apparatus includes wire coil change equipment which serves to reduce the stand- still time of an associated rotary printing machine with wire stitching apparatus and to minimise the risk of accidents. The wire dispensing apparatus comprises two cassettes (1, 2) into each of which a wire coil (13, 14) is insertable and a pair of rollers (38, 39) for conveying wire from either one cassette or the other. Each cassette has two mounting pieces (4, 5) by which it is pushable into or exchangeable in guides (9, 10 or 11, 12) of a cassette mounting (8). One mounting piece has a triangular cross- section while the other has a trapezium cross-section, and the mounting pieces are arranged at 90 DEG to one another. Each cassette has a axle (7) for releasably carrying a coil of wire and a nut (19) for securing the coil against axial displacement. Each cassette also includes electrical switch means to control conveying of the wire, a wire deflecting member, monitoring means to monitor unwinding of the coil and an arm (3) carrying a wire deflecting roller, wire straightening means and a wire guide nozzle. One wire mounting piece is arranged at the free end of arm (3). <IMAGE>

Description

SPECIFICATION Wire dispensing apparatus The present invention relates to wire dispensing apparatus, especially for use in connection with wire stitching apparatus for non-stop stitching in a rotary printing machine.

Wire feed apparatus, which feeds stitching wire in a continuous operation to stitching equipment of a rotary printing machine, must employ at least two wire coils from which the stitching wire is unwound in alteration. During unwinding of a new coil, the spool of the used coil can be removed from a receiving device and be replaced by a new coil.

These basic features are present in known apparatus for example as described in DD-WP 100 437 and DRP 756 731.

The disadvantage of these known apparatus is that operating personnel must, during the running of the machine, remove the residual wire strand from the machine and bring the start of the wire from a newly inserted spool through deflecting rollers, wire straightening equipment and a wire straightening nozzle to wire transport and into a position of readiness.

During this operation, the new wire must also be brought into connection with safety equipment, control equipment or other elements of the machine. Since these described operating steps have to ce carried out with the machine running, the accident risk is so great in the case of some of the smaller rotary printing machines that they must be switched off during the insertion of the new wire strand and the advantage of a device for continuous transport of stitching wire is possibly negated.

When the insertion of the new wire strand is performed within the printing machine while running, extreme caution and attention is required, so that for this reason insertion of the strand takes up a great deal of time.

There is accordingly a need for wire change equipment which is particularly suitable for continuously operable stitching apparatus in a rotary printing machine and by which machine standstill time and the risk of accident can be reduced by relatively umcomplicated means.

According to the present invention there is provided wire dispensing apparatus comprising two cassettes each for housing a respective coil of wire, roller conveying means for conveying wire from the coils in alteration, and support means supporting the cassettes, each of the cassettes being provided with two mounting means removably mounting the cassette in guide means of the support means.

With dispensing apparatus embodying the present invention, the wire can be fed to conveying rollers with reduced risk of accident when the apparatus is running and with reduced effort in removal of residual wire and insertion of a new wire.

In a preferred embodiment, each wire coil is layable into a cassette which possesses receiving elements by which it can be received or exchanged in guides of a cassette mounting.

For the reception of the spool of each coil, a shaft can be secured to the cassette base wall.

A ratchet wheel is preferably mounted on the shaft to be axially undisplaceable, and the wire spool can be pushed onto the shaft, secured against axial displacement, and coupled to the ratchet wheel to be secure against rotation relative thereto.

Moreover, all neccessary components for controlling continuous operation of the conveying means can be arranged in the cassette, for example a pawl which possesses a contact spring, carries a switch rod, and is rotatably mounted parallel to the shaft on the cassette base wall, a spring holding the pawl out of engagement with the ratchet wheel, and wire return equipment. The wire return equipment preferably comprises a bending provided with an abutment, and a resiliently catch. In addition, a contact piece co-operable with the contact spring, and a coil diameter sensor in the form of a feeler lever pivotable with a switch lever about a common rotational axis, can be arranged in the cassette.

Each cassette isprovided with an arm at the outer part of which a deflecting roller, wire straightening equipment and a wire guide nozzle can be arranged in one plane and parallel to the rotational axis of the wire coil.

Through the reception of the wire spool in exchangeable cassettes of the described embodiments, it may be possible to insert the spool free of accident and externally of an associated running rotary printing machine.

Due to the particular structuring of the cassette, it may also be possible to bring the spool as well as the drawn-off strand into the appropriate relationship with components provided for automated non-stop operation of the conveying means. The arm, which is provided at each cassette, with the safety equipment, deflecting roller, wire straightening equipment and wire guide nozzle enchances the exchange operation in that the wire strand can be brought externally of the running machine through further essential parts of the conveying means so that, on the exchange of a used cassette by a new cassette, the start of the new strand is brought directly in front of the conveying means, into which it can then be guided through a slight displacement of the wire strand into a position or readiness.

Preferably, the receiving elements are arranged at the end of the arm, and on a spigot of the shaft, of each cassette. The mounting of each cassette only on these receiving elements, preferably displaced through 90 , in the cassette mounting may provide the advantage that the cassette is firmly held by only two mounting points and can be changed relatively rapidly and free of problems by operating personnel. Through parallel arrangement of two guides one beside the other at the foot of the cassette mounting and through further arrangement of the two guides in the mounting on a common central axis, it is possible to insert the cassette parallelly, with open coil insertion sides thereof facing each other, in the cassette mounting or to remove them from the amounting.By this means, the two coils are almost entirely encapsulated, so that risk of accident is further reduced in this area and the interior of each cassette is at the same time largely protected against ingress of dust.

The receiving element at the end of each cassette are preferably has a triangular crosssection and the receiving element at the spigot of the shaft a trapezium-shaped crosssection, the guides provided for these elements having respectively complementary cross-sections. By virtue of these cross-sectional shapes, uncomplicated mounting means are provided, which enable simple insertion of the cassettes and stable tilt-free support.

An embodiment of the present invention will now be more particularly described by way of example with reference to the accompanying drawings in which: Figure 1 is a sectional elevation, along the line B-B of Fig. 2, of wire dispensing apparatus according to the said embodiment; and Figure 2 is a cross-section of the apparatus on the line A-A of Fig. 1, only one of the two cassettes of the apparatus being shown in detail.

Referring now to the drawings, there is shown wire dispensing apparatus comprising two cassettes 1 and 2 each provided with a jib 3, at the outer end of which is fastened a receiving element 4. A further receiving element 5 is arranged, displaced relative to the first through 90 , at a spigot 6 of a shaft 7 of each cassette. The two cassettes 1 and 2 are received parallelly, with wire spool receiving sides thereof facing each other, in a cassette mounting 8. For this purpose, two guides 9 and 10 for the reception of the receiving elements 4 and two guides 11 and 1 2 for the reception of the receivingf elements 5 are provided at the cassette mounting 8. The cassette mounting 8 is not shown in detail, because it can be constructed according to conditions and the space available.The mounting points for the cassette 1 and 2 could also be different in some circumstances.

The reception of the cassette 1 or 2 in the cassette mounting 8 at the end of the jib 3 increases the stability of the jib 3 and is therefore particularly advantageous.

A wire coil 1 3 or 1 4 is mounted together with a ratchet wheel 1 5 on the shaft 7 in each cassette, the shaft being fastened in the cassette base wall 16. The ratchet wheel 1 5 is arranged to be rotatable, but axially undis placeable, and on its side facing the cassette opening carries an entraining pin 1 7 , which is insertable into a bore 1 8 in the end face of the spool of the coil 1 3 and 14.

Each shaft 7 is provided with a thread at its end so that the spool which has been pushed onto the shaft and coupled with the ratchet wheel can be secured against axial displacement by a nut 1 9. Fastened parallel to the shaft 7 at each cassette base wall 1 G is a spigot 20, on which a pawl 21 is mounted to be rotatable but secure against axial displacement, the pawl being held out of engagement with the ratchet wheel 1 5 by a bent-out leaf spring 22 fastened to the cassette housing.

Mounted on each pawl 21 is a contact spring 23, which contacts a contact element 24 fastened to the housing wall when the pawl 21 notches into the toothing of the ratchet wheel 1 5. In addition, a switch rod 25 provided with a thread is axially displaceably screwed into each pawl 21.

Wire return equipment, which consists of a wound bending spring 27 provided with a kinked portion 26 and of a catch 28, is arranged in each of the cassettes 1 and 2 to be actuable by the respective swithc rod 25.

A feeler lever 30 and a switch lever 31 are mounted to be displaceable and locatable axially, and to extend at an angle relative to each other on a shaft 29 mounted parallel to the rotational axis of the wire spool in the wall of each cassette. The swithch lever 31 is loaded by a tension spring 32, which is fastened to the cassette housing.

A guide roller 33 is provided at each cassette outlet and a wire safety device 34, a deflecting roller 35 and wire straightening equipment 36 consisting of six rollers and a wiere guide nozzle 36 are disposed on each jib 3. When the cassette 1 or 2 is inserted in the mounting 8, the nozzle 36 is disposed in front of the inlet of transport rollers 38 and 39 of a transport device.

When the wire coil 1 3 or 1 4 is almost exhausted, the wire conveying is interrupted by the components which are arranged in the interior of each casette and which co-operate with a wire transport device, the stitching wire being drawn out of the wire conveying nozzle by the wire return equipment. The operation of these components is described in more detail in the applicant's co-pending United Kingdom Patent Application No. 8216820 corresponding to German (Dem. Rep.) patent application No. WP 8 42 B/230 903/8 and filed on 10th June 1982.

After this operation, the complete cassette 1 or 2 can be removed from the cassette mounting 8, and be replaced by a new cassette 1 or 2. The start of the new wire strand in that case already protrudes from the nozzle 37 and need merely be drawn a few centimetres into its position of readiness provided in a recess of the two transport rollers 38 and 39.

For the removed cassette 1 or 2, the nut 1 9 is taken off the shaft 7 and the wire spool is drawn off the shaft 7 while raising the feeler lever 30, the residual wire piece between the spool and nozzle 37 is also removed.

Thereafter, a new spool and coil 1 3 or 14 is pushed onto the shaft 7 while raising the lever 30 and is connected with the ratchet wheel 15. The pawl 21 is held by the leaf spring 22 out of engagement with the ratchet wheel 1 5 during this operation.

The spool is secured against axial displacement by the nut 1 9. The spring 27 is notched into the catch 28 and the start of the wire strand is guided through the device 34 by way of the deflecting roller 35, through the wire straightening equipment 36 and through the nozzle 37. The cassette is thus prepared for reuse.

Claims (11)

1. Wire dispensing apparatus comprising two cassettes each for housing a respective coil of wire, roller conveying means for conveying wire from the coils in alternation, and support means supporting the cassettes, each of the cassettes being provided with two mounting means removably mounting the cassette in guide means of the support means.

2. Apparatus as claimed in claim 1, wherein each of the cassettes includes axle means to carry the associated coil, the axle means being mounted on wall means of the cassette and provided with securing means to secure the coil against displacement axially of the axle means.

3. Apparatus as claimed in claim 2, wherein each of the cassettes includes arresting means to arrest rotation of the coil, the arresting means comprising a ratchet wheel mounted on the shaft and engageable with the coil to be secure against rotation relative thereto, and a paw rotatably mounted on the wall means and movable against a resilient bias to so engage the ratchet wheel as to lock the coil against rotation.

4. Apparatus as claimed in claim 3, wherein each of the cassettes includes electrical switch means to control conveying of the wire by the conveying means, the switch means comprising a first contact member carried by the pawl and co-operable with a second contact member.

5. Apparatus as claimed in either claim 3 or claim 4, wherein each of the cassettes includes wire withdrawl means for moving the wire in a direction counter to a direction of conveying by the conveying means, the withdrawal means comprising a wire deflecting member movable by spring force out of a rest position to move the wire in said counter direction, a releasble catch to hold the deflecting member in its rest position, and a release member cartied by the pawl and displaceable to effect release of the catch.

6. Apparatus as claimed in any one of claims 3 to 5, wherein each of the cassettes includes monitoring means to monitor unwinding of the coil, the monitoring means comprising a pivotable feeler element arranged to be maintained in engagement with the circumference of the coil and an actuating member pivotable with the feeler element and arranged to effect movement of the pawl into engagement with the ratchet wheel.

7. Apparatus as claimed in any one of the preceding claims, wherein each of the cassettes comprises an arm carrying a wire deflecting roller, wire straightening means and wire guide nozzle, the deflecting nozzle, straightening means and guide nozzle being arranged to guide the wire in a single plane.

8. Apparatus as claimed in claim 7, wherein one of the mounting means of each cassette is arranged at the free end of the cassette arm to extend generally perpendicularly thereto and the other mounting means is arranged externally of wall means of the cassette on an extension of axle means for the coil.

9. Apparatus as claimed in claim 8, wherein said one mounting means of each cassette has a generally triangular cross-section and said other mounting means a generally trapezium-shaped cross-section, each guide means receiving a respective of the mounting means having a cross-sectional shape complementary to that of the respective mounting means.

1 0. Apparatus as claimed in any one of the preceding claims, wherein the cassettes are each proviced with a coil insertion opening and are arranged on the support means with the openings facing each other, each cassette being removable from the support means independently of the other cassette.

11. Wire dispensing apparatus substantially as hereinbefore described with reference to the accompanying drawings.