WO2002075738A1

WO2002075738A1 - Device for driving the hub of a tape cartridge, associated cartridge and print equipment using said device

Info

Publication number: WO2002075738A1
Application number: PCT/FR2002/000944
Authority: WO
Inventors: Christophe Peynet; Richard Arrufat; François VERSMISSEN
Original assignee: Ier
Priority date: 2001-03-20
Filing date: 2002-03-18
Publication date: 2002-09-26
Also published as: EP1374239A1; FR2822580A1; FR2822580B1

Abstract

A device for driving the hub (4) of a tape cartridge, adapted in such a way that it can complete and ensure correct positioning of the cartridge on said device. The inventive device comprises at least one tape spool (2) which is adapted in such a way that it can be engaged in said hub and comprising means (11) for capturing said hub, means (10, 30) for displacing the hub, and means (30, 11) for maintaining the hub against stop means (71). The invention also relates to a tape cartridge associated with said device. The device is particularly suitable for installing an ink ribbon cassette in printing equipment.

Description

"Device for driving a hub of a tape cassette, associated cassette, and printing equipment using such a device"

The present invention relates to a device for driving a hub of a tape cassette. It also relates to a tape cassette associated with the device and to printing equipment using such a device.

A tape cassette is, for example, an audio or video magnetic tape cassette, or alternatively, a cassette whose tape is an ink ribbon. Such a cassette generally consists of a housing, two hubs and a band, a first end of which is fixed to a first hub and a second end of which is fixed to the second hub. When using such a cassette, the strip runs through the housing, unwinding around one of the hubs which serves as a reserve, and wraps around the other hub which drives the strip. Equipment for the use of such a cassette therefore comprises a drive device for the drive hub. This device comprises at least one mandrel arranged to be engaged in the drive hub and to be linked to it in rotation. The joint rotation of the mandrel and the drive hub causes the strip to run and be wound up.

When the configuration of the equipment allows, provision may be made for manual placement of the cassette on the drive device. This is the case for equipment where the cassette housing is easy to access, particularly if changing the cassette is infrequent and therefore not very restrictive for the user. However, it may happen during this establishment that a mandrel is not perfectly engaged in the hub which is associated with it. This can result in a tape drive defect, poor reading for a magnetic tape, or poor positioning for a printing ribbon. Devices, such as those intended for front loading of video recorders, take charge of the cassette from its entry into the video recorder and until it is completely positioned on the drive device. However, these loading devices include complex mechanisms and motorizations; they are therefore expensive.

The object of the invention is therefore to propose a drive device comprising simple and inexpensive means to ensure that, during manual placement of a cassette, a mandrel is perfectly engaged in the hub which associated with it, and if necessary to perfect this commitment.

According to the invention, such a drive device for the hub of a tape cassette comprises a mandrel arranged to be engaged in said hub and it is characterized in that said mandrel comprises:

- means for capturing the hub, - means for storing energy in the form of potential energy,

- means for releasing at least part of said energy,

- means for moving the hub,

- means for applying said energy to the displacement means,

- Means for holding the hub against stop means.

Such a device can comprise a shaft and a slider mounted at least in translation with respect to the shaft along an axis of translation and the potential energy can be stored between the shaft and the slider.

The means for storing potential energy may include a compression spring.

The capture means can comprise at least a first retractable cleat from a rest position, said cleat being connected in translation along the axis of translation with the slide.

The energy release means can also include at least one second retractable cleat from a rest position. This cleat may be arranged so that, when the slider is in a waiting position, a retraction of said second cleat authorizes the translation of said slider from the waiting position to a position of potential energy lower than that stored in said position waiting.

In order to reset the device, for example when removing the cassette, it is advantageous for the device to include means for bringing the slider from a lower potential energy position to a higher potential energy position and at least in its waiting position. For the rearming to be complete, the slider may include means for returning the cleats to their rest position.

In the case of a mandrel generally of revolution about a mandrel axis, which can be confused with the axis of rotation of the hub which is positioned on the mandrel, it is preferable that the axis of translation is parallel to the 'mandrel axis. Likewise, the cleats may be movable relative to the slide radially and in respective planes perpendicular to the axis of translation.

In order to wind the strip around the hub, that is to drive the hub in rotation, the device may include means for rotating the hub and the slide and means for rotating the slide and the tree.

A tape cassette adapted to be driven by such a device must particularly comprise at least one drive hub to cooperate with this device. Thus, said hub will include:

means for being taken up by the means for capturing the mandrel,

- means for actuating the means for storing energy in the form of potential energy,

- means for actuating the means for releasing at least part of said energy,

means for transmitting the movement, means for moving, and - Means for being supported by the stop means.

These gripping, action, transmission and support means may be surfaces of the hub arranged, for example on its interior, in order to interact with means of the mandrel. In particular, these surfaces may form a template, that is to say a physical program, intended to be read by means from among the means of the mandrel during the engagement of the mandrel in the hub; that is to say that these surfaces interact successively with these means of the mandrel. A hub being generally cylindrical in shape, the gripping, action, transmission and support means may advantageously be surfaces of revolution around the axis of the hub. Thus, in addition to the ease of manufacture, their interaction with the means of the mandrel will not depend on the position of the latter around its axis.

Other features and advantages of the invention will emerge from the description below, relating to nonlimiting examples. In the accompanying drawings:

- Figure 1 is a perspective representation of three-quarter front of a cassette presented in front of a drive device according to the invention; - Figures 2a and 2b are three-quarter rear representations in section of the operation of a second cleat to allow translation;

- Figure 3 is a longitudinal section on the hub of a cassette according to the invention; - Figure 4 is an exploded view viewed from three-quarters rear of a slide for a mandrel according to the invention;

- Figure 5 is a partially cut representation of the slide of Figure 4 mounted on a shaft according to the invention; and,

- Figures 6a to 6d are longitudinal sections on a mandrel to illustrate interactions between a mandrel and a hub according to the invention. FIG. 1 represents a driving device 1 which mainly comprises two mandrels 2 mounted on a frame and at least one motor 9 for driving at least one of the two mandrels in rotation around a mandrel axis X. FIG. 1 also represents a tape cassette 3 mainly consisting of two hubs 4 rotatably mounted in a housing 5 and around which a tape 6 is wound. The cassette 3 also comprises a handle 8 for its manual insertion on the device 1 in the direction A .

A mandrel 2, a longitudinal section of which is shown diagrammatically in FIG. 6a, mainly comprises a slide 10 mounted on a shaft 20. The shaft is mounted to rotate freely in a bearing 70 of the frame 7. The bearing defines for the mandrel an axis rotation coincides with the axis of the mandrel X. The shaft is a volume of revolution around the axis of the mandrel. The shaft 20 and the slide 10 are linked in rotation about the axis X by a key 21 (see FIG. 5). The motor 9 can be connected to the rear end 29 of the shaft to drive the shaft and the slide and therefore the mandrel 2 in simultaneous rotation.

The mandrel further comprises a helical spring mounted in compression between a nozzle 23 of the shaft 20 and a bearing surface 16 of a body 13 of the slide 10.

The slide is a mobile assembly which comprises, in addition to the body 13, a first cleat 11 and a second cleat 12, a return spring 14 for the cleats and a skirt 15 for centering a hub 4 on the mandrel 2. The tabs are arranged to be able to slide radially along B in the body of the slide, that is to say along an axis intersecting with the axis X of the mandrel and in a plane substantially perpendicular to the axis of the mandrel. As particularly shown in FIGS. 4 and 5, the first and second tabs respectively comprise a first finger 13 and second finger 123, forming radially protrusions on the exterior surface of the body 13 of the slide 10.

The return spring 14 is a bending blade, a central part 140 of which is immobilized in the direction of bending on a boss. 131. The shape of the boss allows the blade to bend parallel to the radial direction B during a radial displacement of one of the ends of the blade. A first end 141 of the blade is introduced into a housing 1 12 in the first cleat 1 1. A second end 142 is introduced into a housing 122 in the second cleat 12. Each of the ends 141, 142 is therefore linked in displacement respectively to a cleat 11, 12. A rest position for the cleats is a position in which they exert no bending force on the blade 14. It is this rest position which is illustrated in FIG. 2a for the second cleat 12.

The second cleat 12 comprises a ring 121 to be associated with a stop groove 22 of the shaft 20. Said ring can slide radially in the stop groove 22 when the slide is in a waiting position on the shaft 20. We will now describe a hub according to the invention with reference to FIG. 3. The hub 4 is generally cylindrical in shape around a hub axis Y. It includes surfaces 48 on its exterior to guide the hub in rotation. in the housing 5 and a substantially cylindrical surface 49 for winding the strip 6. It further comprises on its interior surfaces of revolution around the hub axis Y. They are, in the direction of engagement of the mandrel in the hub, i.e. from a rear opening to an anterior opening of the hub:

a stop surface 40 which serves as a reference for the longitudinal positioning of the hub on the mandrel 2,

a centering surface 41, substantially cylindrical or very slightly conical, associated with the skirt 15 of the slide 10 and which serves for centering the hub on the mandrel, that is to say to make the hub axis Y substantially coincide with the mandrel axis X when the centering surface is positioned on the skirt,

a trunk of release cone 42 whose diameter is reduced from the diameter of the centering surface, a release cylinder 43 whose diameter is equal to the smallest diameter of the release cone trunk,

an erasing cone trunk 44 whose diameter is reduced from the diameter of the release cylinder, an erasing cylinder 45 whose diameter is equal to the smallest diameter of the erasing cone trunk,

a truncated support cone 46 whose diameter increases from the diameter of the erasing cylinder, and,

- A connecting cylinder 47 whose diameter is equal to the largest diameter of the support cone trunk and connects from the last with the front opening of the hub.

The trunks of erasing cone 44 and of support 46 form with the erasing cylinder 45 an annular segment 456. It projects inside the hub between the release cylinders 43 and the connection 47. To allow the drive in rotation of the hub by the mandrel the hub comprises in the centering surface 41 notches 28 are formed in the centering surface 41 at the periphery of the rear opening of the hub. They are arranged to cooperate with lugs 27 of the skirt 15. To allow indifferent positioning of the hub on the skirt it is advantageous to provide notches over the entire periphery of the opening at a step divider of the pitch between two neighboring pins on the skirt.

The first finger 1 13 comprises, on one end furthest from the axis of the mandrel X, three contact zones for interacting with the interior surfaces of the hub. From front to back, they are successively:

- A retraction zone 1 16 which is a truncated cone sector whose inclination on the mandrel axis X is substantially equal to the inclinations of the release cone 42 and the erasing cone 44 on the hub axis Y ,

an erasing zone 11 which is a cylinder sector, and, - A support area 1 18 which is a truncated cone sector whose inclination on the mandrel axis X is substantially equal to the inclination of the support cone 46 on the hub axis Y.

The second finger 123 comprises, on one end furthest from the axis of the mandrel X, two contact zones for interacting with the interior surfaces of the hub. From front to back, they are successively:

a retraction zone 126 which is a truncated cone sector whose inclination on the mandrel axis X is substantially equal to the inclination of the release cone 42, and,

- A release zone 127 which is a cylinder sector.

We will now describe the operation of the device with reference to Figures 6a to 6d, that is to say the successive interactions between the mandrel 2 and the hub 4. In Figure 6a, the slider is immobilized in a waiting position , that is to say that it is blocked in translation on the shaft 20 by the engagement of the ring 121 in the stop groove 22 and that the helical spring 30 is kept in compression between the end piece 23 of the shaft and the bearing face 16 of the slide. An operator presented the cassette 3 in order to roughly align the hub axis Y with the axis of the mandrel X without any interaction having taken place between the mandrel and the hub.

In Figure 6b, the mandrel is more deeply engaged. Thus, the retraction zone 1 16 of the first finger 1 13 has slid over the release cone 42. this has resulted in partial retraction of the first cleat in the body 13 of the slide 10. Once the release cone has been crossed by the first finger , the penetration of the mandrel continues and its erasing zone 1 17 runs through a generatrix of the erasing cylinder 43 until the first finger comes into contact with the annular segment 456. In FIG. 6c, the mandrel is still more deeply engaged. The first finger 1 13 has crossed the annular segment. Thus, the retraction zone 1 16 has slid along the erasing cone 44 until the erasure of the first finger in the slide. The erasing zone 1 17 then traversed a generatrix of the erasing cylinder 45. During the successive retractions of the first finger, the end 141 of the blade 14 was bent. Thus, when the first finger 11 has crossed the segment 456, it has come out of the slide under the action of the spring blade until the erasing zone comes into contact with the connecting cylinder 47 of the hub 4. The hub 4 is then captive between the first finger and the frame 7.

After the segment has been crossed by the first finger, the retraction zone 126 of the second finger has slid over the release cone 42 which has caused the second cleat 12 to retract into the body 13. Once the release cone has been crossed by the second finger, this is kept retracted by the action along B of the release cylinder on the release area 127 of the second finger 123. The second cleat being sufficiently retracted, the ring 121 which had remained engaged in the groove stop 22 of the shaft 20 (see Figures 6a, 6b, and 2a) is no longer engaged and can slide on the shaft as particularly illustrated in Figure 2b. The spring 30 compressed between the shaft and the slide exerts on the bearing face 16 of the latter a thrust in the direction A. This thrust causes the displacement of the slider in the same direction A simultaneously with the relaxation of the spring which gradually releases part of the energy it stored.

In Figure 6d, the slide is thus moved. During this movement, the support zone 1 18 of the first finger came to abut on the support cone 46 of the hub, transmitting to the latter the thrust of the helical spring 30. The hub moved jointly with the slide in the direction A until the abutment surface 40 meets the abutment 71 of the frame 7.

Thus, it suffices that the operator, who sets up the cassette 3, engages the mandrel 2 in the position of FIG. 6c for the mandrel to perfect the correct positioning of the hub on the device 1. Residual potential energy in the helical spring 30 keeps the hub pinched between the support zone 1 18 and the stop 71.

When removing the cassette, in direction Z, it is the support cone 46 of the hub 4 which, pressing on the support zone 1 18, transmits the movement of the cassette to the slide. The spring compresses under the action of the slide until the slide has reached or passed its position in FIG. 6c. The distance between the first and the second valve is suitably chosen so that, when the support zone 1 18 is in contact with the support cone 46, the release zone 127 is no longer in contact with the release cylinder 43 (see Figure 6d). As soon as the slide again reaches its standby position, the second cleat is found opposite the stop groove 22; no longer subject to the action of the return spring 14, the ring 121 engages there which stops the movement of the slide. As the removal of the cassette continues, the hub continues to move in the direction of withdrawal Z; the support zone 1 18 then slides on the support cone 46, the first cleat therefore disappears under the segment, releasing the cassette. The device is reset and is in the position of FIG. 6a, ready to receive a new cassette. In a case where the device is disarmed, that is to say that the slide on the mandrel is in the position of FIG. 6d, prior to the installation of the cassette, it is automatically reset after installation and removal of this cassette. For this, a retraction groove 1 19 (see FIGS. 6d and 5) allows the first cleat 1 1 to be erased when the annular segment 456 passes when the cassette is put in place by the operator, who must himself even the perfect positioning of the hub on the mandrel. The hub and the mandrel are then in the position of FIG. 6d. The removal of this cassette makes it possible to rearm the device, that is to say to bring it back to the configuration of FIG. 6a.

In FIGS. 6a-6d, only the second cleat makes it possible to immobilize the slide with the aid of its ring 121 in a single stop 22 of the shaft 20. In Figures 4 and 5 the two tabs are designed identical and the first cleat 1 1 has a ring 1 1 1 to be engaged in a reduced end 26 of the shaft 20. In this case the connecting cylinder 47 of the hub serves as a release cylinder for the first cleat. This provision is a safety measure to avoid untimely disarming of the device.

Of course, the invention is not limited to the examples which have just been described and numerous modifications can be made to these examples without departing from the scope of the invention. For example, the inner surfaces of the hub may not be cones or cylinders, not even be surfaces of revolution, provided that said surfaces exert on the mandrel, as it engages in the hub, actions allowing the capture of the hub by the mandrel then after release of a potential energy the displacement of the hub until its perfect positioning on the mandrel.

The figures represent tabs facing upwards on the figures. These representations are arbitrary and the tabs can be oriented indifferently according to the orientation of the mandrel around its axis.

Likewise, the cleats may not be in the same longitudinal plane. We can also simplify the tree by keeping the stop groove only a shoulder furthest back. This shoulder is sufficient to immobilize the slide in its standby position and makes it possible to have a single reduced section of the shaft from the end piece to the shoulder.

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Claims

1. Device (1) for driving a hub (4) of a tape cassette (3), comprising a mandrel (2) arranged to be engaged in said hub, characterized in that the mandrel comprises:

- means (1 1) for capturing the hub,

- means (10,20,30) for storing energy in the form of potential energy,

- means (12) for releasing at least part of said energy,

- means (10,30) for moving the hub,

- means (1 6.30) for applying said energy to the displacement means,

- Means (30) for holding the hub against stop means (7).

2. Device according to claim 1, characterized in that it further comprises a shaft (20) and a slide (10) mounted at least in translation relative to the shaft along a translation axis (X) and in that that potential energy is stored between the tree and the ram.

3. Device according to claim 2, characterized in that the capture means comprise at least a first cleat (1 1) retractable from a rest position, said cleat being linked in translation along the translation axis (X) with the slide (10).

4. Device according to claim 2 or 3, characterized in that the energy release means comprise at least a second cleat (1 2) retractable from a rest position and in that, when the slide (1 0) is in a waiting position, a retraction of said second cleat allows the translation of said slide from the standby position to a position of potential energy lower than that stored in said standby position.

5. Device according to claim 4, characterized in that it comprises means (1 1) for bringing the slide (10) from a lower potential energy position to a higher potential energy position and at least in its position wait.

6. Device according to one of claims 1 to 5, characterized in that the energy storage means comprise a compression spring (30).

7. Device according to one of claims 3 to 6, characterized in that the slide (10) comprises means for returning (14) at least one cleat (1 1, 12) to its rest position.

8. Device according to one of claims 1 to 7, comprising a frame (7), characterized in that the mandrel (2) is mounted free in rotation relative to said frame around a mandrel axis (X) and in what it includes means (15) for making a hub axis (Y) coincide with said mandrel axis.

9. Device according to claim 8, characterized in that the translation axis is parallel to the mandrel axis (X).

10. Device according to one of claims 3 to 9, characterized in that the tabs (1 1, 12) are movable relative to the slide (10) in respective planes perpendicular to the axis of translation (X).

1 1. Device according to one of claims 1 to 10, characterized in that it further comprises means (21) for rotating connection of the hub and the slide and means (27) for rotating connection of the slide and the shaft .

12. Device according to one of claims 4 to 1 1, characterized in that the energy storage means comprise at least one stop groove (22) on the shaft (20) and sliding means (121 ) for the second cleat (12) in the stop groove under the opposing actions of the return means (14) and the hub (4) on the cleat.

13. Tape cassette (3) comprising at least one drive hub (4) for cooperating with a device (1) according to one of claims 1 to 12 characterized in that said hub comprises:

- means (44,45,46,456) to be taken by the capture means (1 1) of the mandrel, - means for actuating (46) the means for storing energy in the form of potential energy,

- means (42,43) for actuating the means for releasing at least part of said energy,

- means (46) for transmitting the movement of the means for moving, and,

- Means (40) for being supported by the stop means.

14. Cassette according to the preceding claim characterized in that at least one of the gripping, action, transmission and support means is a surface of revolution around the axis of the hub.

15. Cassette according to claim 13 or 14 characterized in that the gripping, action, transmission and support means form a template on an inner face of the hub, said template being intended to be read by means from among mandrel means during engagement of the mandrel in the hub.

16. Printing equipment comprising a drive device according to any one of claims 1 to 12.