GB2023540A

GB2023540A - Cassettes

Info

Publication number: GB2023540A
Application number: GB7903138A
Authority: GB
Original assignee: Agfa Gevaert AG
Current assignee: Agfa Gevaert AG
Priority date: 1978-01-31
Filing date: 1979-01-30
Publication date: 1980-01-03
Also published as: DE2804137C3; FR2416630A7; DE2804137A1; DE2804137B2; GB2023540B

Abstract

A cassette for spooling strip material, especially microfilm, includes an elastic belt 5 passing around guide rulers 6, 7, 8, 9 and 10 and a spool core 3a. The leading edge 4a of a strip is fed to the nip 20 between the moving belt 5 and the rotating spool core 3a and transported between the belt and the core back to the nip 20, thereby beginning the reel of strip material. In this type of cassette, damage to the strip material could result if the belt 5 broke or if an operator forgets to put a spool 3 in the cassette. Accordingly, the invention provides a device, 8 and 22 to 25 which is responsive to the tension of the belt 5 and which co-operates with an indicating member 26 which is caused to be retracted into the cassette housing 1 when the tension in the belt falls below a predetermined value. The retraction of the member 26 closes a switch 32 to stop the spooling operation. <IMAGE>

Description

SPECIFICATION Improvements in and Relating to Cassettes The present invention relates to a cassette for spooling strip material and especially to a cassette of the general type disclosed in German Offenlegungsschrift No. 25 26 483 (British Patent Application No. 24303/76). Serial No.

1,551,973.

A cassette of the type referred to is used in fully automatic processing devices for film material, for example, in microfilm recording devices. In such a device, a cassette containing a spool is inserted in the device and the leading end of the film passing through the processing device is conveyed into the cassette by transport means arranged in the device and is there wound on automatically. The automatic winding-on of the leading edge of the film is brought about by an endless belt accommodated in the cartridge that passes over part of the core spool. The leading edge of the film is fed in between the belt and the spool core and guided around the core by the belt.

It may happen that the endless belt, which is made, for example, of rubber, tears as a result of high strains. It is also possible that the operator may forget to insert a take-up spool in the cassette. In both cases it is not possible to wind the film fed to the cassette correctly and it is highly likely that the film material would be damaged if attempted.

According to the present invention, there is provided a cassette for spooling strip material which comprises a spool, an endless belt running over the spool for guiding strip material around the spool, means responsive to the tension in the belt which, in operation, co-operates with an indicating means to give an indication at the outside of the cassette when the tension in the belt is lower than a predetermined value.

The indicating means is preferably a member that assumes a first position when the tension in the belt is greater than the predetermined value and a second position when the tension in the belt is less than the predetermined value. The indicating member may, for example, operate a switch in an automatic processing device that, if actuated by the indicating member, for example, when the belt is broken or no spool is present in the cassette, activates for example, an alarm signal that draws the attention of the operator to the fault, and may stop the transport of the strip material to the cassette.

Two forms of cassette according to the present invention will now be described, by way of example only, with reference to the accompanying drawings in which: Fig. 1 is schematic sectional view of the first form of a cassette which has been inserted in a processing device, which is shown in fragmentary section; Fig. 2 isa schematic sectional view of a portion of the second form of cassette.

With reference to Fig. 1 a cassette housing 1 houses a spool 3 for microfilm, the spool having a core 3a and being mounted on a shaft 2. An endless band or belt 5 made of elastic, rubber-like material is stretched over guide rollers 6, 7, 8, 9 10 and over the spool core 3a, in such a manner that it winds round the greater proportion of the circumference of the spool core.

The cassette is provided with a lid 15, which is hinged to the cassette housing 1 and which can be swung away from the housing.

An arm 12 is pivotally connected to the shaft 11 of the guide roller 9, by means of cover plates 13 (only one of which is shown). At the end of the arm 12 remote from guide roller 9, the guide roller 10 is mounted by means of further cover plates 14 (only one of which is shown). A leaf spring 16, secured at one end to the inside of the cassette lid 1 5, lies with its free end pressing resilientiy against the swivel arm 12, so that the guide roller 10 is urged in the direction of the spool core 3a.

A resiliently flexible guide strip 1 7 is secured at one end to the cassette lid 15, and at its other end to a nose 1 2a of the swivel arm 12, proximate the guide roller 10.

When winding on a film strip onto the spool 3, the spool is rotated in the direction of the arrow A by means of drive means (not shown). The film is fed by transport means (not shown) into the cassette through a slot 1 8 in the cassette housing 1, the end of the film is conveyed through the channel formed by the guide strip 1 7 and a section 5a of the belt 5 to a nip 20 where it is caught between the core 3a of the spool 3 and the endless belt 5 and guided round the spool core between the spool core and the belt. For further details of the cassette reference should be made to German Offenlegungsschirft No. 25 26 483, which corresponds to British Patent Application No. 24303/76.

A rocker 21 mounted in the cassette is pivotable about a shaft 22. The left-hand portion of the rocker (as seen in Fig. 1) has an inverted Ushaped cross-section and between the arms 23 of that portion, the guide roller 8 is mounted by means of a shaft 24. The right-hand portion 25 of the rocker 21 (as seen in Fig. 1) is so shaped and disposed that it can engage a switching pin 26.

This switching pin is movably mounted in the cassette housing 1 and is acted upon firstly by the rocker 21, which tends to urge it upwardly, and secondly by a spring 27 which tends to urge it downwardly into a position in which it is retracted within the cassette. 28 denotes a shoulder against which the spring 27 acts.

Figure 1 shows the cassette in position in a cassette recess 30 of a film processing device 31, for example, a microfilm recording device.

Members (not shown) hold the cassette in operating position (as shown in Fig. 1). A switch 32 having an operating lever 33 is arranged relative to the cassette recess 30 in such a manner that it can be operated by the switching pin 26 projecting beyond the periphery of the cassette housing 1 (as is the case in the state shown in Fig. 1). If the pin 26 is retracted within the housing, the switch 32 is in an open position which causes the operation of the device to be interrupted and an alarm lamp to be lit up but, if the pin 26 projects from the cassette housing (as seen in Fig. 1) the switch 32 is in a closed position and the device can be duly operated.

If, as in Fig. 1, the endless belt 5 is intact and the spool 3 has been inserted correctly in the cartridge, the tension in the belt 5 tends to cause the rocker 21 to pivot about shaft 22 in an anticlockwise direction (as seen in Fig. 1) so that the pin 26 is pushed upwardly out of the cartridge against the action of the spring 27. If the tension in the endless belt 5 is not sufficient to counteract the effect of the spring 27, for example when the belt is torn or the operator has forgotten to insert a spool in the cartridge, the switching pin 26 is retracted into the cassette under the action of the spring 27.

Fig. 2 shows the second embodiment in which the guide roller 8 is mounted between the arms 34 of a U-shaped plate. To the portion connecting the arms of the U-shaped plate, there is fastened a switching pin 35. The switching pin 35 is in turn movably mounted with respect to the cassette housing 1 and is acted upon firstly by the tension in the endless belt 5 and secondly by a coil spring 37 acting between the housing 1 and a shoulder 36 which is fastened to the switching pin.

In the case of the embodiment shown in Fig. 2, the switching pin 35 is retracted into the cassette when the endless belt 5 is correctly tensioned while, if the endless belt is torn or the spool is missing, the switching pin 35 is pushed out of the cassette by the action of the spring 37. The switching pin 35 can be arranged to operate a switch to interupt the feed of the film to the cassette.

Claims

1. A cassette for spooling strip material which comprises a spool, anndndless belt running over the spool for guiding strip material around the spool, means responsive to the tension in the belt which, in operation, co-operates with an indicating means to give an indication at the outside of the cassette when the tension in the belt is lower than a predetermined value.

2. A cassette as claimed in claim 1, wherein the indicating means is a member that assumes a first position when the tension in the belt is greater than the predetermined value and a second position when the tension in the belt is below the predetermined value.

3. A cassette as claimed in claim 2, which includes a housing wherein the arrangement is such that the indicating member projects beyond the housing when in the first position and is retracted within the housing when in the second position or vice versa.

4. A cassette as claimed in claim 2 or claim 3, wherein the indicating means is a pin wherein the arrangement is such that, in operation, the pin is acted upon by a weight and/or resilient means to tend to move the pin towards the first position and the action of the tension in the belt tends to move the pin to the second position or vice versa.

5. A cassette as claimed in any one of claims 1 to 4, wherein the tension responsive means includes a movable guide roller over which, in operation the endless belt passes.

6. A cassette as claimed in claim 5 and any one of claims 2 to 4, wherein the arrangement in such that, the guide roller assumes a first position when the tension the belt is greater than the predetermined value and a second position when the tension in the belt is less than the predetermined value and the guide roller and the indicating member so co-operate that each of the first and second positions of the indicating member corresponds to a different one of the first and second positions of the guide roller.

7. A cassette as claimed in claim 5 or claim 6, wherein the guide roller is mounted at one end of a rocker, the other end of which co-operates with the indicating means.

8. A cassette as claimed in claim 7, wherein the rocker is mounted within the cassette housing.

9. A cassette as claimed in any one of claims 1 to 8, wherein the cassette comprises a rotatable spool having a spool core, an endless belt running over guide rollers and over the spool core, the latter lying outside the closed loop formed by the endless belt, and means for retaining on the spool core strip material which has been introduced between the spool core and the portion of the endless belt lying over the spool core.

10. A cassette substantially as hereinbefore described with reference to and as illustrated in, Fig. 1 or Fig. 2 of the accompanying drawings.

11. A microfilm recording device which includes means responsive to the indication given by a cassette as claimed in any one of claims 1 to 10 to stop the operation of the device when the indicating means indicates that the tension in the endless belt is lower than the predetermined value.