FR2537763A1 - TAPE CASSETTE COMPRISING A BAND PROTECTION COVER - Google Patents

Abstract

THE INVENTION RELATES TO A TAPE CASSETTE INCLUDING A TAPE PROTECTION CASE. IN THIS CASSETTE CONTAINING A CASSETTE CASE 11 SHAPED IN TWO HALVES 13, 14 INCLUDING TWO COILS 15, 16 ON WHICH A STRIP 22 PROTECTED BY A COVER 12 AND IN WHICH GUIDING GROOVES 20A, 21A ARE PROVIDED IN THE SIDE WALLS OF THE CASE AND TAPE GUIDES 20B, 21B ARE FITTED ON THE ENDS OF THE SIDE WALLS OF THE CASE, THE GROOVES 20A, 21A AND THE GUIDES 20B, 21B RESPECTIVELY HAVE A SEAMLESS CONFIGURATION ON THE HEIGHT OF THE CASE 11. APPLICATION IN PARTICULAR TO VIDEO CASSETTES.

Description

-1 2537763

  Tape cassette having a protective cover of the tape. The present invention relates in a manner

  tape cassettes with a protective cover

  tection of the tape, and more particularly a tape

  a cassette housing intended to receive

  see a magnetic tape, and a protective cover of the tape that is constituted by an outer bonnet element

  and by an inner cowl element When not in use

  not read the tape cassette, the outer element of the hood is closed so as to cover the front surface of the strip which is exposed or exposed along the front part of the housing, and the inner element of the hood covers the

back surface of the band.

  In general, a tape cassette

  of the type used with a video tape recorder

  a cassette case used to house a tape, and

  a protective cover of the latter.

  Tection of the strip is arranged to be closed

  when the tape cassette is not in use, so

  cover and protect the tape that is exposed or

  exposed along the front of the cassette case.

  The protective cover of the belt opens when the case

  used, so as not to interfere with an operation

  extraction of the tape, during which the tape

  removed from the cassette case so as to be

  on a predetermined path of tape in the record

  video tape tracer 'Traditionally, the hood of

  tape was usually arranged as a single element covering only the surface

  front (magnetic surface) of the magnetic tape Cepen-

  In the meantime, it has recently been proposed

  in which the protective cover of the

  de is arranged to provide more protection

  In accordance with these tape cassettes,

  proposed, the protective cover of the belt is con-

  staggered by an outer bonnet element that covers the

  front surface of the band, and by mid inner part of

  pot that covers the back surface of the band That is

  say that the protective cover of the tape has a

  in two elements: In these cassettes with

  The outer bonnet element can be supported with the possibility of rotation relative to the cassette casing. However, the inner bonnet element can not be supported with the possibility of pivoting.

  the usual way using trunnions, being

  This is why the inner bonnet element was arranged to open and close by sliding along guiding grooves formed in the casing.

the cassette box -

  The cassette casing consists of an upper half and a lower half. The upper half has a side wall that connects to side walls of the lower half.

  of these sidewalls is equal to half of the

  cassette case The guide grooves in

  above, which guide the inner element of

  pot, are arranged so as to be continuous in

  side walls of the upper and lower halves

  during, the guide grooves can not have a smooth and uniform continuity at the parts of

  connection o the side walls of the upper halves

  re and lower are connected, depending on the accuracy

  with which upper and lower halves are

  This is why there is a stepped part at the connection parts indicated above and

  if the guide grooves do not have continuity

  smooth and even tee, the inner bonnet element can not

  not be open and closed in a uniform way -

  In some cases, the parts of the walls

  of the cassette casing are used as guides to guide the band which is housed inside

  said housing However, the connecting parts can

  coincide with the guides and a stepped part may

  be trained on the guides in this case, the guides

  are inadequate for guiding the belt and the belt can be damaged if guided by

  such guides having a stepped portion.

  As described above, the wood

  cassette tier is made up of upper halves

  and lower However, when assembling these self-

  upper and lower band, the band which rests on the

  the front of the cassette can be pinched between the

  side kings of the upper and lower halves when

  that they are connected This is why there is a problem that the band can suffer

  damage during the assembly operation of the wood

tier of cassette.

  Therefore, a general object of the present invention is to provide a new and useful tape cassette having a tape guard, in

  which the problems described above are removed.

  These issues are resolved in accordance with

  the invention in a tape cassette comprising a wood

  cassette tier having an upper half and a lower half, which are connected to each other; a band housed inside said cassette case; an openable and closed cover which is located on the front face of said cassette case and covers the strip disposed along a predetermined path along the front face of said cassette case when the hood

  is closed, this cover comprising an external element

  to cover a front surface of said strip located on said predetermined strip path, and an inner member for covering a rear surface of said strip located on said predetermined strip path; a pair of curved guide grooves formed in side walls of said cassette case and serving

  guiding a pair of projecting parts of said element

  bonnet interior and guiding the movement of this inner bonnet member when said openable and closed bonnet opens and closes; and a couple of guidebooks

  formed on end portions of the walls la-

  of said cassette case and on the front face thereof, so as to guide said band along said predetermined band path when the cassette is not

  used, characterized in that said guide grooves

  curves and said tape guides have respective

  a seamless configuration over the height of the said

cassette case.

  Cam-forming grooves for guiding

  the inner bonnet element and the tape guides for guiding the tape when the cassette is not

  used, are provided respectively on the walls la-

  In the bottom half of the casing according to the present invention, the inner casing member is uniformly guided along the camming grooves since the camming grooves are

  no connection element and this guarantees an opening

  stability and closure of the protective cover of the

  In addition, when assembling the cassette tape

  according to the present invention, it is possible to

  tape in a predetermined band

  inside the cassette case under the guide action provided by the tape guides, in an assembled state o

  the coils are placed on the lower half, that is,

  say in an assembly state before connecting the top half of the cassette to the lower half of

  the latter It follows that the operation-tion, -when

  the lower half is connected to the upper half

  top, can be made easily, without any risk that the band is pinched between the side walls of the halves

  upper and lower and therefore damaged.

  In addition, since there is no seal at the belt guides, the latter can be guided by

  these guides without any risk of damage.

  According to another characteristic of the present-

  In the invention, a tape cassette is provided in which

  the cam grooves, which are formed in the side walls of the lower half adjacent to the front portion of the cassette housing, are formed of

  in such a way that the size of the opening level above

  camming grooves is wide In the case of

  the strip according to the present invention, parts

  protruding parts forming the cam members of the element.

  inside the bonnet can easily penetrate

  the cam grooves from the top openings

  the latter when assembling the casset-

  band, and the assembly operation of said cassette-

  It can be facilitated. It is possible to provide a large width of the level of the upper openings of the camming grooves, if these upper openings

  are arranged so as to comprise a horizontal part

  rectilinear, which makes the operation of

  In addition, a matrix of

  which is arranged to form sharp edges, i.e. a matrix which is not damaged even after repeated operation, can be used to form the tape cassette. That is why the tape cassette according to the present invention also presents

  advantages from the point of view of its molding.

  Other features and benefits of the

  present invention will emerge from the description given

  hereinafter, with reference to the accompanying drawings, on the

  1A, 1B and 1C show an embodiment of a tape cassette according to the present invention respectively according to a plan view (with a right half of an upper half of the cassette and a part of the protective cover of

  strip torn off), front view and elevation view

lateral aspect;

  FIG. 2 is a side elevational view of

  a vertical section of the cassette taken along the line II-II in Figure 1A;

  Figure 3 is a side elevational view of

  in vertical section showing the upper and lower halves of a cassette case in the separated state;

  Figure 4 is a side elevational view of

  in vertical section showing a front part of the cassette

  bandaged in the state o the protective hood of the ban-

de is open;

  Figures 5 and 6 are elevational views

  side respectively showing a protective cover

  the tape and a locking mechanism in the state where the outer hood member is closed and in the state where the hood outer member is open;

  Fig. 7 is a diagram for explaining

  mention the meshing of protruding parts of the protective cover of the strip with cam grooves, when assembling the tape cassette; FIG. 8 shows the side walls of the lower left half of the cut opening.

  in this lower half, according to a larger view.

  of scale, as well as two metal matrices that

  read the formation of these side walls ;,

  FIG. 9 represents a portion of

  left-hand side of one of the two metal matrices re-

shown in Figure 8; and

  Figure 10 shows another form of reali-

  of a tape cassette according to the present invention.

  the upper and lower halves are separated

  Rees. As shown in FIGS. 1A, 1B and 1C and 2, a tape cassette 10 includes a cassette casing 11 and a tape guard 12, which is

  provided on the front part IA of the cassette case.

  The cassette casing 11 is constituted by an upper half 13 and a lower half 14, as shown in FIG. 3. These upper and lower halves 13 and 14 are both constituted

  by an acrylonitrile butadiene styrene (ABS) resin.

  A supply spool 15 and a take-up spool 16 are housed inside the cassette casing 11, in a state where the spools 15 and 16 are pushed against the spools.

  lower halves 14 by a leaf spring 17 essential-

  A brake mechanism 18 is provided inside the cassette housing 11 at a location which is located at the top of the cassette housing 11.

  neighborhood of a rear part 11 B of this box A

  cutout 14a is formed in the central portion

  before the lower half 14 and load pads-

  (not shown) of a video tape recorder

  (not shown) enter this opening

  14a when extracting a magnetic tape

  cassette casing 11 Lateral parts projection 4.

  14 b and 14 c which extend in a relative way on

  the front of the cassette case 11, are formed respectively

  on the right and left sides of the half

lower 14.

  A side wall 14 d which has a high

  half of that of the cassette casing 11, extends along the outer edges of the side portions 14b and 14e. Elements 20 and 21 of the side wall 14d, which are located on the right and the left of the cut opening 14c, respectively have a height which is

  approximately equal to the height of the case of casset-

  These side wall elements 20 and 21 are

  Therefore, there is contact with the lower surface of an upper plate 13a of the upper half 13. Mainly S-shaped and 2a-shaped camming grooves are provided respectively in the elements.

  side wall 20 and 21 so that the reasures

  Cams are reciprocally opposite one another on both sides of the cut-off opening 14. In addition, semi-cylindrical shape guides 20b and 21b are provided.

  are respectively provided on the wall elements la-

  20 and 21, vis-à-vis the cut opening -14 a.

  The magnetic strip 22 is located on a

  predetermined band path 22 A when the tape cassette

  10 is not used Band 22 is taken from the box

  15, crosses the lateral portion 14b, is guided by the strip guides 20b and 21b so as to

  extend across the front part of the opening

  cut 14a, crosses the lateral portion 14c, and is then

  sided by the receiving reel 16, forming this predetermined tape path 22 A The tape guides 20b and 21b

  guide the web 22 only when the web cassette

  10 is not used-and that the band 22 is housed at

  inside the cassette case 11, these bank guides

  20b and 21b are formed respectively on the elements

  20 and 21 and are not trained to

  side walls of the upper and lower halves

  13 and 14 that are connected Therefore, the joints, which otherwise would exist in the tape guides

  if they were formed by connecting the

  sides of the upper and lower halves do not exist in the 20b and 21b

  are provided on the side wall elements 20 and 21.

  That is, no tiered or irregular part

  does not exist on tape guides 20b and 21b, where it

  There is a contact with the band.

  22 is guided uniformly by the web guides b and 21b, without any risk that said web is scratched and damaged. The protective cover 12 of the band is

  two elements and includes an external element

  23 and an inner hood member 24

  cover 12 of tape protection is mounted on the

  before tape A of cassette 11 and take a representative

  shown in Figure 2 when closed, and a state

  4 when it is open.

  ra described later in this description,

  the exterior and interior hood elements 23 and 24

  in order to simultaneously protect the front surface

  (magnetic surface) and the back surface of the strip 22.

  The outer hood member 23 has a front portion 23a extending to the upper surface of the cassette housing 1 so as to form a portion of

  this upper surface of the cassette casing 11,

  side kings 23 and 23 c and arms 23 d and 23 e which support

  The arms 23 d and 23 e extend downward from the wall portion

  before 23a which constitutes part of the upper surface

  cassette casing 11, and are respectively located at positions facing the sidewall members 20 and 21 within the opening

  cut 14a, when the cover 12 of the ban-.

  de is closed The arms 23 d and 23 e come out of the opening

  cut 14a when the hood 12 of protection of the ban-

  opens as shown in Figure 4, and again enter the cut opening 14a when the hood 12

  Protective tape is closed as shown on.

  FIG. 2 As shown in a view on a larger scale in FIGS. 5 and 6, trunnions 23b-1 and 23c-1 are situated respectively substantially at the centers of the sidewalls 23b and 23c A sidewall -13 b of the upper half 13 cooperates with

  the side wall 14 d of the lower half 14 so that

  re to form bearings for the journals 23b-1 and 23c-1. Therefore, the hood outer member 23 is rotatably mounted in a state in which the journals 23b-1 and 23c-1 are supported by the bearings

  indicated above, which are located essentially midway

height of cassette housing 11.

  The inner cowl element 24 has an elongated upper plate 24a and an inclined wall 24b which slopes down towards the front portion of the cassette housing 11 from the top plate 24a. The width of the wall inclined 24 b is slightly less than the distance between the arms 23 d and 23 e the inclined wall 24 b'compos includes protrusions 24 c (only one is shown) at its central portion, and arm portions 24 d (of which only is shown) at its lower part The projections 24 c formed on the inclined wall 24 b respectively engage in

  holes in the arms 23 d and 23 e The par-

  the arms 23 d comprise respectively a part

  protruding cam follower member (only one protruding portion is shown)

  Twenty-Fourth Cam Trainers Engage in Reasons

  20a and 21a so that the formal parts

  As a result, the inner cowl member 24 is hinged to the cassette housing 11, in a state where the projections 24 e

  following bodies are engaged in the reas-

  On the other hand, the inner cowl element 24 is hinged to the outer cowl element 23 in a state where the protrusions 24 d of the inclined wall 24b are supported with the possibility of pivoting, in the holes formed in the arms 23 d and 23 e Therefore, the rotational position of the inner housing member 24 relative to the outer housing member 23 is controlled by the camming grooves

a and 21 a.

  When the hood 12 of protection of the ban-

  of is closed, the hood outer member 23 takes a

  rotated position in the opposite direction of the hands of a

  As shown in FIG. 2, in this state the camming follower members 24 are respectively located in the lower positions P1 within the camming grooves 20a and 21a, and

  the inner cowl element 24 is stopped in a posi-

  The lower edge of the inclined wall 24b is in contact with the lower edge of the front wall 23a of the outer hood member 23 Therefore, the front surface (magnetic surface ) and the upper edge of the strip 22 are covered by the wall 23a of the outer cover member 23, and the rear surface (base surface or non-magnetic surface) and the lower edge of the strip 22 are covered by the inclined wall 24b of the element

  hood interior 24, and the strip 22 is completely

  In addition, the elongate plate 24 has

  the inner cowl element 24 assumes a high position

  which is the same as the high position of the upper plate 13a of the upper half 13, so as to cover the upper opening at the level of the part

  before cassette case 11 As is shown in FIG.

  5 in FIG. 5, the cover 12 for protecting the strip is normally pushed in its closing direction.

  by a torsion spring 25, and a hook 26a of a

  The locking spring 26 blocks a protruding portion 23b-2 which is provided on the inside of the side wall 23b so as to lock the cover 12 to protect the web in its locked position. The torsion spring is mounted on the web. trunnion 23b-1 so that one of its arms is mounted on a projecting portion 25 which is formed on the side wall of the upper half 13, while its other end is mounted on a

  protruding portion 23 b-3 which is formed on the inner face

* top of the side wall 23 b.

  When introducing the tape cassette

  in a cassette housing (not shown) in the

  interior of the video tape recorder (not shown),

  a lever 28 for unlocking or removing the lock.

  The video tape recorder contacts the lock lever 26 as shown in FIG. 6 so as to pivot the lock lever 26 counterclockwise. Therefore, the lock lever 26 has 26 deviates from the projecting portion 23 b-2 and the locking applied to the band protection cover 12 is suppressed during an operation, during which the tape cassette 10 located inside the cassette case is loaded into a predetermined position inside

  of the video tape recorder as a result of the lowering

  cassette housing, the hood outer member 23 is rotated clockwise on

  approximately 900 against the force exerted by the

  torsion spell 25, under the action of a nipple 29 of the

  video tape recorder It follows that the parties

  protruding 24 th cam follower members of the element

  Inner cowling 24 is guided respectively along the camming grooves 20a and 21a, and the cowl inner member 24 rotates in a clockwise direction.

  of a watch around the trunnions 23 b-1 and 23 c-1 of such

  so that the inner edge of the inclined wall 24b does not come into contact with the web 22 In other words, the camming grooves 20a and 21a are essentially S-shaped so that the leading edge of the inclined wall 24 b does not meet and does not damage the band 22 when the cover 12 of the protection-band opening. The camming grooves 20a and 21a are not

  not consist of groove connection sections

  forming cams, which are formed in the side walls

  both of the upper and lower halves, but are formed respectively in the side wall members 20 and 21. Therefore, there are no joints or irregularities such as steps in the cam grooves 20a and 21a, and grooves can be formed with high precision That is why the 24 th protruding parts forming follower cam members

  move uniformly along the grooves

  mant cams 20a and 21a when the protective cover 12 of the strip is open and closed, without any interruption at the joints, which would otherwise occur if the camming grooves were formed in the side walls

  of the two upper and lower halves, and that is why

  In addition, there is no undesired clearance between the projecting cam follower portions 24 e and the camming grooves 20 a and 21 a, even though there is no undesirable clearance between them.

  after an extremely large number of ope-

  re and closing of the hood 12 of protection of the band, and the reliability of this hood 12 and parts thereof

  associates is extremely high.

  When the hood 12 of protection of the ban-

  of is open, the inner hood element 24 is blocked

  in a position shown in Figure 4, by the

  24 c and by the prominent parts 24 th

  In this state, the elongated plate 24a does not come into contact with the upper plate 13a of the cam. The cam follower members are located in the upper positions P 2 within the camming grooves 20a and 21a. lower half 13 That is to say that the elongated plate

  24 rests slightly above the plane.

  that upper 13 has and there is a slight deflection for

  the continuation of the rotation-of the inner element of

  pot 24 in a clockwise direction. As a result, forces will not act simultaneously at both ends of

  the inner cowl element 24, that is to say

  that no force will act simultaneously on the edge of the -

  elongated plate 24a and the protruding portions 24f formally

  cam follower bodies When the force applied to the hood 12 of

  protection of the band by the nipple 29 in order to maintain

  open the hood 12 protection tape is sup-

  award-winning, this cover 12 for protecting the band is

  automatically rotated in the opposite direction of the

  a watch by the force exerted by the spring 25, and takes the closed position shown in the figures

2 and 5.

  Hereinafter, we will describe the operation of assem-

  in which the tape cassette 10 is assembled

  thanks to the connection of the upper and lower halves

  13 and 14, and the constitution of the tape cassette according to the present invention, which facilitates

  the assembly operation Since the parts as-

  associated with the camming grooves 20a and 21a are formed

  similarly on both sides of the cassette case-

  11, the description given below will relate to the rationale

  nure forming cam 2 the right and on the parts that him

  are associated, and we will not give the description in

  relative to the left-hand cam groove 20a and the

parties associated with it.

  The tape cassette 10 is assembled by means of the connection of the upper and lower halves 13 and

  14, as will be described below, in a state where the

  pot 12 of tape protection is fully open and is mounted temporarily on the upper half 13 as

  this is shown in Figure 7.

  First, the supply spool and the take-up spool 16 are disposed within the lower half 14. At this stage of the assembly operation,

  pulls the web 22 from the reels so that

  be guided by tape guides 20b and 21b By con-

  22, the band 22 follows the predetermined band path 22A within the lower half, 14, said band 22 extending across the front portion of the cutout opening 22a. predetermined

  22 A is formed, place the upper half 13 on the

  above the lower half 14 so as to cover this lower half 14, and the upper half 13 is connected to this lower half 140 In the predetermined band path 22 A, the band 22 is guided over its entire width by the guides. 20b and 21b therefore, there is no risk that the web 22 is pinched between the side wall 13b and 14d of the upper and lower halves 13 and 14 and is damaged when the upper half 13 is connected to Therefore, the connection operation of the upper and lower halves 13 and 14 can easily be performed in a state in which

  the band 22 is sufficiently protected.

  In addition, when connecting the upper and lower halves 13 and 14, the protruding portion 24 e forming cam follower member of the right hood 12 of

  protection of the band penetrates into a superior opening

  21a-1 of the camming groove 21a, from the space

  located above this upper opening The part-

  protruding 24 e forming cam follower member penetrates inside the cam groove 21a after the

  upper and lower halves 13 and 14 were connected

  and that the protective cover 12 of the strip is

  me. When opening and closing the protective cover 12 of the band, the protruding portion 24 e forming

  cam follower on the right moves between the

  Pl and P 2 within the cam groove 21a The position P 2 is located slightly below

  the upper opening 21 a-1, and the portion of the cam

  between the P 2 position and the opening of the cam groove 21 a is not used as a groove

  Therefore, as will be described below,

  after, the width of the upper opening 21 a-1 between the opening and the position P 2 of the cam groove

  21a receives a dimension greater than the width of the reason

  the camming portion 21a between the positions Pl and p 2 # so that the projecting cam follower portion 24e can be easily inserted into the groove

  forming a cam 21a when the upper and lower halves

  In addition, the wide design of the upper aperture 21a-1 allows easier molding of the lower half 14 through the use of

of metal matrices.

  In other words, the upper opening 21a-1 is defined by the vertical part 21a-2 and by a horizontal part 21a-3 as shown in the figures

  3 and 7 The upper opening 21 a-1 is wide, in particular

  in the direction of the horizontal part 2 la-3

  for this reason that the 24th projecting part forming

  cam follower on the right easily enters

  the wide upper opening 21 a-1 when the parts

  upper and upper 13 and 14 are connected, as

  is indicated by an arrow A in FIG. 7, and penetrates

  It will then be inside the cam groove 21a when the tape cover 12 is closed after the top and bottom halves 13 and 14.

  have been connected Therefore, the operation of inserting

  24 e forming cam follower members within the camming grooves 20a and 2a can be implemented easily.

  also realize the upper opening 21 a-1-of

  re that it is wide, by providing a rectilinear portion 2a-4, which is indicated by a broken line in Figure 7, instead of the horizontal portion 21a-3 In this case, the connecting operation of the upper and lower halves

  13 and 14 will be identical to the decri-

  hitherto, and the projecting camming portions 24a can be easily introduced into the camming grooves 20a and 21a. The upper end portion of the cam groove 2a is inclined and the vertical portion 21a -2 is made in one piece with a top wall forming part of

  two walls defining the camming groove 21a; -

  while the horizontal part 21 a-3 is formed of a

  alone with a lower wall forming part of

  say two walls defining the cam groove 21a.

  Once the upper and lower halves

  13 and 14 were connected as previously described, fixed together with screws (no

  shown) to form the tape cassette 10.

  In addition, the upper and lower halves

  13 and 14 can be connected together with the

  upper half 13 fixed, instead of the lower half 13

  14, and up the lower half 14 so that

  re to form the tape cassette 10.

  Hereinafter, we will describe the metallic matrices

  who perform the formation of the cam groove

  21 a (20 a) and the cut opening 4 a located in the

  14, with reference to FIGS. 8 and 9.

  Since the cam groove 2a is curved, i.e. substantially S-shaped,

  one of the metal matrices used to form

  sea groove forming cam 21 a can not be dismissed

  in a direction parallel to the wall element la-

  21, and this matrix must be spaced in a direction perpendicular to the side wall element

  21 once the forming operation of the groove forms

  mant cam 21a is completed In addition, because of the structure

  of the side wall 14 d in the vicinity of the cam groove 21 a, another metal matrix, which is used to form a wall 30 at the level of the

  inner part of the cut opening 14a, is inde-

  pendent of the metal matrix indicated above and

  which is used to form the cam groove 21a.

  Fig. 8 shows the lower half 14 in the vicinity of the cam groove 21a, as well as the metal dies that are used to form that portion of the lower half 14 In Fig. 8, the metal die 40 is a sliding type die which is used to form the camming groove 21 a

  and the side wall element 21 of the lower half

  re 14 A metal matrix-41 is used primarily

  to form the wall 30 After the training operation

  of the camming groove 21a and the like, the metal matrix 40 is

  direction marked by an arrow B, and the man

  metal trice 41 in a perpendicular direction

in the drawing of Figure 8.

  The problem, which is very important, is

  determine the separation plan at which the

  In this embodiment, a vertical plane SL which has a straight line L passing through a starting end of the horizontal portion 21a-3 shown in FIG. 3 is selected in the present embodiment. , in view of the fact that the upper end of the groove forming

  cam 2 la is realized in the form of a superior opening

  21 Figure 9 shows a part of the

metal matrix 41.

  According to the metal matrices 40 and

  41 described above, we obtain the following notable effects:

  (i) the part of the metal matrix 41 which forms the horizontal part 2 la-3

  does not need to be done with extreme precision.

  high, and that is why we can

  easily fabricate the metal matrix 41.

  (ii) in relation to the case where the separation plan.

  matrix is located in a very close position

  of the wall 30, the metal matrix 41 has a thickness of

  shown in Figure 9 at the level of one of

  its pointed ends This thickness t is sufficient

  important so that the metal matrix 41 is

  sufficiently robust at said end point

  Therefore, even after repeated use

  of the metal matrix 41 to form the envi-

  sages, the end point of the metal matrix 41

do not break.

  Figure 10 shows another form of

  tape cassette according to the present invention.

  In Figure 10, the front of the cassette

  is represented in a state in which the

  upper and lower 50 and 52 are separated Upper half 50 has one element

  lateral wall 51 at its front face.

  This side wall element 51 is equal to the height of the cassette case. A flat recess 51b having an S-shaped side wall 51 is formed.

  in the side wall element 51 On the other hand the

  lower section 52 comprises a vertical wall element

2537763.

  53 This vertical wall element 53 has a wall la-

  S-shaped side wall 53 has at its front portion, and

  a horizontal surface element 53 bo.

  The upper and lower halves are connected

  50 and 52 by inserting the vertical wall element

  53 in the flat recess 51b of the element of pa-

  lateral king 51, as represented by a dashed line in FIG. 10 In this connected state,

  the S-shaped side walls 51 a and 53 a are

  reciprocally vis-à-vis and constitute a reason-

  Cam-shaped groove 54 which corresponds to the cam groove 21a previously described. This cam groove 54 has no joints on the height of the cassette housing and is smooth and continuous.

  upper part of the S-shaped side wall 51 a and the

  horizontal surface 53b in the vertical wall element 53 define an aperture 55 which corresponds to

  the upper opening 21 has previously been described.

  We first introduce the salient part

  24 e forming cam follower member within

  the opening 55 which is formed when the upper halves

  and lower 50 and 52 are connected, and it is

  then feeds into the camming groove 52 which is also

  when the upper and lower halves

re 51 and 52 are connected.

  In accordance with this second form of

  According to the present invention, the displacement of the projecting cam follower portion 24 e along the cam groove

  In addition, as in the case of the first

  first embodiment described above, the ope-

  In addition, the web 22 is guided over the entire width by a web guide 51c which is provided on the front portion.

  of the side wall element 51, without being scratched or damaged

  magée, as in the case of the first embodiment

previously described.

  In addition, since no short grooves

  , be is provided in the side wall element 51 and

  in the vertical wall element 53, it is not necessary

  to use special metal matrices-of the type

  slip for the formation of these parts It is pos-

  use of ordinary metal dies to form the sidewall member 51 and the wall member

  53, which makes this second form of

  advantageous from the point of view of forming said parts.

  In addition, the present invention is not limited to

  these forms and on the contrary, we can introduce different variants and modifications

  without departing from the scope of the present invention.

2537763,

Claims (8)

  A tape cassette having a cassette casing (11) having an upper half (13.50) and a lower half (14.52), which are connected to each other; a band (22) housed inside said cassette casing; a cover (12) which can be opened and closed   and which is located on the front side of said boltier de casset-   and covers the strip arranged along a predetermined path   mined (22 A) along the front side of the casset-   when the hood is closed, this hood comprising a   outer member (23) for covering a front surface   of said band on said predetermined band path   and an inner member (24) for covering a rear surface of said strip on said predetermined strip path; a pair of curved guide grooves (20a, 21a, 54) formed in side walls of said cassette housing and for guiding a pair of protruding portions (24e) of said hood inner member and guiding the movement of this element bonnet interior when said openable and closed hood opens and closes, and a pair of web guides (20b, 21b,   51 (c) provided on end portions of the walls   of said cassette housing on the front face thereof to guide said tape along said predetermined tape path when the cassette is not   used, characterized in that said guide grooves   curved webs (20a, 21a, 54) and said web guides (20b, 21b, 51c) respectively have a configuration   without a seal on the height of said cassette case (11).   2 tape cassette according to claim 1, characterized in that said lower half (14) of said   cassette housing has two lateral wall elements   the (20,21) reciprocally facing each other, located on the right and left sides of the cassette case on   the front of the latter and having respectively a high   which is approximately equal to the height of this wood.   tier, and that said curved guide grooves (20a, 21a) are formed in surfaces facing each other vis-à-vis   said side wall elements and extend substantially   the entire height of the said side wall elements   3 tape cassette according to claim 2,   characterized in that two sidewall elements com-   respectively, said strip guides (20b, 21b),   swiveled on end portions of these sidewall elements on the front of said cassette housing, so as to   guide said band on said predetermined band path   when the tape cassette is not in use.   4 tape cassette according to claim 1, characterized in that said upper half (50) of said   cassette housing has two sidewall elements   (51) on the left and right sides of the   cassette case on the front of the latter and pos-   sedant respectively a height which is approximately   substantially at the height of this housing, that each of said sidewall members has a first wall   lateral curve (51a) which defines a wall of said rims   curves (54), that said lower half   (52) of said cassette casing has two vertical wall members (53) on the right-hand sides and   left of said cassette case on the front of this   deny and each having a second side wall   be (53 a) which defines the other wall of said grooves.   curved guidance, and that the curved guide grooves   are formed in cooperation by the said first and second   curved sidewall when said upper halves   upper and lower are connected so as to be facing each other.   Tape cassette according to claim 4, characterized in that said pair of side wall elements respectively comprises said web guides 2537763 i   (51c) provided at end-points of these ele-   side wall on the front of the cassette casing-   to guide the web following said web path   predetermined when the cassette is not in use.   Strip cassette according to claim 1, characterized in that each of said guide grooves (20a, 21a, 54) has a wide upper opening (21a-1.55) at its upper end and   that said projecting parts (24a) of said element   bonnet penetrate into said guide grooves   curves through said upper openings   res when the upper and lower halves   of said cassette stand are connected to each other.   7 tape cassette according to claim 6,   characterized in that said upper openings   (21 a-1) are defined by the upper walls and   behind said curved guide grooves (20a, 21a) and said upper walls of said grooves have,   at their upper extremities, a green part straight line (21 a-2).   8 tape cassette according to claim 6, characterized in that the wide upper openings   (21-a, 55) are defined by upper walls and   (51a, 53a) of said curved guide grooves (20a, 21a, 54), and said inner walls (53a).   said curved guide grooves (20a, 21a, 54) have   tooth at their upper extremities, some horizontal (21 a-3, 53 b).   9 tape cassette according to claim 6,   characterized in that said upper openings   (21 a-1) are defined by upper and lower walls   of said curved guide grooves (20a, 21a), which said upper walls of said grooves have,   at their upper extremities, a green part   straight line (21 a-2) and that said lower walls   said grooves have at their ends   upper mites, a horizontal part (21 a-3).