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Claims  |
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I claim:
1. A cleaning apparatus for a playing and/or recording machine, where said
machine has:
a. a structure defining a recess to receive a tape cassette, said recess
having a forward portion to receive a front portion of said cassette, and
a rear portion to receive a rear portion of said cassette;
b. a head carrying member which carries a rotating head element and has a
curved peripheral surface;
c. first and second guide means movable between first and second
nonoperating positions, respectively, and first and second operating
positions, respectively, said first guide means in said first nonoperating
position being located at a first retracted guide location, said second
guide means in said second nonoperating position being located at a second
retracted guide location, said first guide means being arranged so that
with a tape cassette in the recess, the first guide means in moving from
the first nonoperating position to the first operating position engages a
first tape portion positioned along a first section of the front portion
of the cassette and moves the tape outwardly form the cassette into
engagement with a first side portion of the peripheral surface of the head
carrying member, said second guide means being arranged so that with the
tape cassette in the recess, the second guide means in moving from the
second nonoperating position to the second operating position engages a
second tape portion positioned along a second section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a second side portion of the head carrying member;
said cleaning apparatus comprising:
a. a housing having a front portion, a rear portion, and first and second
side portions, said housing being adapted to be positioned in the recess
of the machine;
b. a cleaning ribbon mounted in said housing in a manner to have a first
retracted position and a second cleaning position, said ribbon having
first and second end portions operatively connected to said housing, and a
third intermediate portion which, with the ribbon in its first retracted
position, and with the housing positioned in said recess, extends along a
forward edge portion of the housing, with first and second sections of the
intermediate ribbon portion being positioned forwardly of said first and
second retracted guide locations, respectively, when the housing is
positioned in the recess of the machine;
c. a locating element mounted to said housing at a stationary location at
the front portion of the housing, said locating element being positioned
between said first and second retracted guide locations, when the housing
is positioned in the recess of the machine;
d. said locating element being positioned forwardly of a third adjacent
section of said ribbon which extends between said first and second
sections, said locating element being positioned, with said housing
located in the recess, relative to the first and second guide means and
relative to the peripheral surface of the head carrying member, in a
manner that when said first and second guide means engage said first and
second sections of the intermediate ribbon portion and move outwardly to
their first and second operating positions, said locating element
restrains outward movement of said third section of the intermediate
ribbon portion so as to maintain said third ribbon section out of
engagement with the peripheral surface of the head carrying member, and in
a manner that the peripheral surface of the head carrying member is
engaged by said cleaning ribbon along an arcuate length of the peripheral
surface which is less than an arcuate length of engagement of the tape
when the tape in said tape cassette is in said operating position
extending in a curved path around the peripheral surface of the head
carrying member;
e. first and second spool means rotatably mounted to said housing at first
and second spool locations to engage first and second sprockets,
respectively, of the machine, the first and second end portions of the
ribbon being connected to said first and second spool means, respectively;
f. said locating element comprising a roller rotatably mounted in said
housing so as to engage said cleaning ribbon with a relatively low
frictional engagement.
2. A method of cleaning a playing and/or recording machine, where said
machine has:
a. a structure defining a recess to receive a tape cassette, said recess
having a forward portion to receive a front portion of said cassette, and
a rear portion to receive a rear portion of said cassette;
b. a head carrying member which carries a rotating head element and has a
curved peripheral surface;
c. first and second guide means movable between first and second
nonoperating positions, respectively, and first and second operating
positions, respectively, said first guide means in said first nonoperating
position being located at a first retracted guide location, said second
guide means in said second nonoperating position being located at a second
retracted guide location, said first guide means being arranged so that
with a tape cassette in the recess, the first guide means in moving from
the first nonoperating position to the first operating position engages a
first tape portion positioned along a first section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a first side portion of the peripheral surface of the head
carrying member, said second guide means being arranged so that with the
tape cassette in the recess, the second guide means in moving from the
second nonoperating position to the second operating position engages a
second tape portion positioned along a second section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a second side portion of the head carrying member;
said method comprising:
a. providing a cleaning apparatus comprising:
1. a housing having a front portion, a rear portion, and first and second
side portions, said housing being adapted to be positioned in the recess
of the machine;
2. a cleaning ribbon mounted in said housing in a manner to have a first
retracted position and a second cleaning position, said ribbon having
first and second end portions operatively connected to said housing, and a
third intermediate portion which, with the ribbon in its first retracted
position, and with the housing positioned in said recess, extends along a
forward edge portion of the housing, with first and second sections of the
intermediate ribbon portion being positioned forwardly of said first and
second retracted guide locations, respectively, when the housing is
positioned in the recess of the machine;
b. said method further comprising:
1. positioning a locating element in said housing at a stationary location
at the front portion of the housing, said locating element being
positioned between said first and second retracted guide locations, when
the housing is positioned in the recess of the machine, with said locating
element being positioned forwardly of a third adjacent section of said
ribbon which extends between said first and second sections;
2. inserting said housing in the recess;
3.
3. engaging said first and second sections of the intermediate ribbon
portion with said first and second guide means and moving the first and
second guide means outwardly to their first and second operating
positions,
4. restraining outward movement of said third section of the intermediate
ribbon portion by means of said locating element so as to maintain said
third ribbon section out of engagement with the peripheral surface of the
head carrying member, and in a manner that the peripheral surface of the
head carrying member is engaged by said cleaning ribbon along an arcuate
length of the peripheral surface which is less than an arcuate length of
engagement of the tape when the tape in said tape cassette is in said
operating position extending in a curved path around the peripheral
surface of the head carrying member,
c. said method being further characterized in that there are first and
second spool means rotatably mounted to said housing at first and second
spool locations to engage first and second sprockets, respectively, of the
machine, said method further comprising connecting the first and second
end portions of the ribbon to said first and second spool means,
respectively, and said locating element comprises a roller rotatably
mounted in said housing so as to engage said cleaning ribbon with a
relatively low frictional engagement. 3. A cleaning apparatus for a
playing and/or recording machine, where said machine has:
a. a structure defining a recess to receive a tape cassette, said recess
having a forward portion to receive a front portion of said cassette, and
a rear portion to receive a rear portion of said cassette;
b. a head carrying member which carries a rotating head element and has a
curved peripheral surface;
c. first and second guide means movable between first and second
nonoperating positions, respectively, and first and second operating
positions, respectively, said first guide means in said first nonoperating
position being located at a first retracted guide location, said second
guide means in said second nonoperating position being located at a second
retracted guide location, said first guide means being arranged so that
with a tape cassette in the recess, the first guide means in moving from
the first nonoperating position to the first operating position engages a
first tape portion positioned along a first section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a first side portion of the peripheral surface of the head
carrying member, said second guide means being arranged so that with the
tape cassette in the recess, the second guide means in moving from the
second nonoperating position to the second operating position engages a
second tape portion positioned along a second section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a second side portion of the head carrying member;
said cleaning apparatus comprising:
a. a housing having a front portion, a rear portion, and first and second
side portions, said housing being adapted to be positioned in the recess
of the machine;
b. a cleaning ribbon mounted in said housing in a manner to have a first
retracted position and a second cleaning position, said ribbon having
first and second end portions operatively connected to said housing, and a
third intermediate portion which, with the ribbon in its first retracted
position, and with the housing positioned in said recess, extends along a
forward edge portion of the housing, with first and second sections of the
intermediate ribbon portion being positioned forwardly of said first and
second retracted guide locations, respectively, when the housing is
positioned in the recess of the machine;
c. a locating element mounted to said housing at a stationary location at
the front portion of the housing, said locating element being positioned
between said first and second retracted guide locations, when the housing
is positioned in the recess of the machine;
d. said locating element being positioned forwardly of a third adjacent
section of said ribbon which extends between said first and second
sections, said locating element being positioned, with said housing
located in the recess, relative to the first and second guide means and
relative to the peripheral surface of the head carrying member, in a
manner that when said first and second guide means engage said first and
second sections of the intermediate ribbon portion and move outwardly to
their first and second operating positions, said locating element
restrains outward movement of said third section of the intermediate
ribbon portion so as to maintain said third ribbon section out of
engagement with the peripheral surface of the head carrying member, and in
a manner that the peripheral surface of the head carrying member is
engaged by said cleaning ribbon along an arcuate length of the peripheral
surface which is less than an arcuate length of engagement of the tape
when the tape in said tape cassette is in said operating position
extending in a curved path around the peripheral surface of the head
carrying member;
e. said locating element comprising a roller rotatably mounted in said
housing so as to engage said cleaning ribbon with a relatively low
frictional engagement.
4. A method of cleaning a playing and/or recording machine, where said
machine has:
a. a structure defining a recess to receive a tape cassette, said recess
having a forward portion to receive a front portion of said cassette, and
a rear portion to receive a rear portion of said cassette;
b. a head carrying member which carries a rotating head element and has a
curved peripheral surface;
c. first and second guide means movable between first and second
nonoperating positions, respectively, and first and second operating
positions, respectively, said first guide means in said first nonoperating
position being located at a first retracted guide location, said second
guide means in said second nonoperating position being located at a second
retracted guide location, said first guide means being arranged so that
with a tape cassette in the recess, the first guide means in moving from
the first nonoperating position to the first operating position engages a
first tape portion positioned along a first section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a first side portion of the peripheral surface of the head
carrying member, said second guide means being arranged so that with the
tape cassette in the recess, the second guide means in moving from the
second nonoperating position to the second operating position engages a
second tape portion positioned along a second section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a second side portion of the head carrying member;
said method comprising:
a. providing a cleaning apparatus comprising:
1. a housing having a front portion, a rear portion, and first and second
side portions, said housing being adapted to be positioned in the recess
of the machine;
2. a cleaning ribbon mounted in said housing in a manner to have a first
retracted position and a second cleaning position, said ribbon having
first and second end portions operatively connected to said housing, and a
third intermediate portion which, with the ribbon in its first retracted
position, and with the housing positioned in said recess, extends along a
forward edge portion of the housing, with first and second sections of the
intermediate ribbon portion being positioned forwardly of said first and
second retracted guide locations, respectively, when the housing is
positioned in the recess of the machine;
b. said method further comprising:
1. positioning a locating element in said housing at a stationary location
at the front portion of the housing, said locating element being
positioned between said first and second retracted guide locations, when
the housing is positioned in the recess of the machine, with said locating
element being positioned forwardly of a third adjacent section of said
ribbon which extends between said first and second sections;
2. inserting said housing in the recess;
3. engaging said first and second sections of the intermediate ribbon
portion with said first and second guide means and moving the first and
second guide means outwardly to their first and second operating
positions,
4. restraining outward movement of said third section of the intermediate
ribbon portion by means of said locating element so as to maintain said
third ribbon section out of engagement with the peripheral surface of the
head carrying member, and in a manner that the peripheral surface of the
head carrying member is engaged by said cleaning ribbon along an arcuate
length of the peripheral surface which is less than an arcuate length of
engagement of the tape when the tape in said tape cassette is in said
operating position extending in a curved path around the peripheral
surface of the head carrying member.
c. said method being further characterized in that said locating element
comprises a roller rotatably mounted in said housing so as to engage said
cleaning ribbon with a relatively low frictional engagement. |
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Claims |
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Description |
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BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates to a method and apparatus for cleaning
operating components of a video player/recorder.
2. Background Art
In recent years, video player/recorders have become quite popular.
Typically, there is a video head which either records or plays back the
video portion of the playing tape, an audio head which performs the same
functions for the sound portion of the tape, an erase head, and possibly
other components which engage the tape. In the proper operation of the
player/recorder, it is desirable that the surface portion of at least some
(and desirably all) of these components which contact the tape be cleaned
periodically. There are in the prior art cassette cleaners which have a
cassette housing in which is mounted a cleaning ribbon. In operation, the
cassette housing is placed into a playing receptacle of the
player/recorder, and the start knob or button is moved to the "on"
position so that guide members of the player/recorder engage the cleaning
ribbon and bring it into engagement with at least the drum of the video
head, and in some instances, the other operating components which would
normally come into contact with the playing tape.
In some player/recorders, the drum in which the playing head is mounted
rotates at a high rate of speed. In other player/recorders, the drum for
the playing head remains stationary, while the playing head itself rotates
at a high rate of speed along the circumference of the drum. During the
normal mode of operation, the magnetic tape which is either being played
or on which the recording is being made moves along its length at a
controlled rate of speed adjacent the playing head. If the drum of the
playing head is stationary, the relative movement between the magnetic
tape and the drum is at a substantially lower level. On the other hand, if
the drum is rotating at a high rate of speed (e.g. 1000 to 2000
revolutions per minute), the relative speed between the drum and the
magnetic tape is rather high.
In general, the cassette cleaners have had the cleaning ribbon mounted in
one of two ways. In one arrangement, the cleaning ribbon is moved out of
the cassette housing into engagement with the drum of the cleaning head,
and the cleaning ribbon does not move along its axial length. Thus, it is
the rapid rotation of the drum of the cleaning head which accounts for the
relative movement between the cleaning ribbon and the drum. In the second
arrangement, the cleaning ribbon is mounted on spools within the cassette
housing so that after it is moved out of the cassette housing into
cleaning engagement with the drum (and possibly other components of the
player/recorder), the cleaning ribbon moves along its axial length at
substantially the same rate of speed as the magnetic tape in the normal
mode of operation of the player/recorder. In either case, there is
relative movement between the cleaning ribbon and the drum of the playing
head.
One of the major problems in providing such cassette cleaners is the
sensitivity of the operating components of the various player/recorders.
For example, the cassettes for magnetic tapes generally have two spools
which engage spindles of the player/recorder. During normal operations,
the magnetic tape will be unwound from one spool and wound onto the other.
If the spindles (or possibly other operating components of the
player/recorder) sense a resistance to rotation greater than a certain
level, this will generally activate a shutoff mechanism in the
player/recorder. The reason for this is that the increased resistance
indicates a problem, and the player/recorder shuts off to avoid damage to
the magnetic tape or possibly damage to the player/recorder itself.
In addition, a number of player/recorders have other shutoff mechanisms.
For example, there are the capstan and pinch roller which grip opposite
sides of the tape, with the capstan being rotated under power so as to
cause rotation of the pinch roller and move the magnetic tape along its
length at a controlled rate. If for some reason the capstan is not causing
the corresponding rotation of the pinch roller, so that the tape is not
being moved, this might also trigger a shutoff mechanism.
Generally, the magnetic tape is made of a quite thin, rather flexible, low
friction material. However, the cleaning ribbon of a cassette cleaner, in
order to perform its cleaning function properly, has a somewhat different
structure. First, it will generally be made of an absorbant material so
that it can absorb a cleaning liquid. Second, since the cleaning is
achieved by a wiping action against the drum, and possibly other
components of the player/recorder, the friction of the cleaning ribbon
moving relative to the drum may be somewhat greater than the friction of
the conventional magnetic tape moving through the player/recorder and
against the drum. Further, the cleaning ribbon is quite often made
somewhat thicker than the conventional magnetic tape, so it would be more
absorbant, with the result that if the cleaning ribbon is arranged so that
it moves through the player/recorder along generally the same path as the
magnetic tape, the greater stiffness of the cleaning ribbon (relative to
the magnetic tape) might create greater resistance to the movement of the
cleaning ribbon. Overall, these various operating characteristics of the
cleaning ribbon sometimes create sufficient resistance to the operating
components of the player/recorder so as to trigger an automatic shutoff
mechanism of the player/recorder, thus prematurely stopping the cleaning
action.
A further complicating factor is that quite commonly the action of the
cleaning fluid increases the frictional force resulting from engagement of
the wetted ribbon against the drum. Thus, there is a tendency for the
cleaning ribbon to create an excessive resisting force to the rotation of
the drum, thus prematurely triggering the shutoff mechanism of the
player/recorder. There have been various attempts to lower the resistance
created by the cleaning ribbon, such as modifying the material used, the
thickness of the material, the material's absorbancy, etc. In some
instances, such attempts to decrease the frictional resistance or other
resistance have the effect of diminishing the cleaning effectiveness of
the ribbon.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a cleaning apparatus
and method for a video player/recorder, particularly adapted to alleviate
some of the problems noted above, while properly performing a cleaning
function.
The cleaning apparatus of the present invention is arranged to clean a
playing and/or recording machine, where the machine has:
a. a structure defining a recess to receive a tape cassette, said recess
having a forward portion to receive a front portion of said cassette, and
a rear portion to receive a rear portion of said cassette;
b. a head carrying member which carries a rotating head element and has a
curved peripheral surface;
c. first and second guide means movable between first and second
nonoperating positions, respectively, and first and second operating
positions, respectively, said first guide means in said first nonoperating
position being located at a first retracted guide location, said second
guide means in said second nonoperating position being located at a second
nonoperating guide location, said first guide means being arranged so that
with a tape cassette in the recess, the first guide means in moving from
the first nonoperating position to the first operating position engages a
first tape portion positioned along a first section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a first side portion of the peripheral surface of the head
carrying member, said second guide means being arranged so that with the
tape cassette in the recess, the second guide means in moving from the
second nonoperating position to the second operating position engages a
second tape portion positioned along a second section of the front portion
of the cassette and moves the tape outwardly from the cassette into
engagement with a second side portion of the head carrying member.
The cleaning apparatus comprises a housing having a front portion, a back
portion, and first and second side portions. The housing is adapted to be
positioned in the recess of the machine.
A cleaning ribbon is mounted in the housing in a manner to have a first
retracted position and a second cleaning position. The ribbon has first
and second end portions operatively connected to the housing, and a third
intermediate portion which, with the ribbon in its first retracted
position, and with the housing positioned in the recess, extends along a
forward edge portion of the housing. First and second sections of the
intermediate ribbon portion are positioned forwardly of the first and
second retracted guide locations, respectively, when the housing is
positioned in the recess of the machine. There is a locating element
mounted to the housing at a stationary location at the front portion of
the housing. This location element is positioned between the first and
second retracted guide locations, when the housing is positioned in the
recess of the machine.
The locating element is positioned forwardly of a third adjacent section of
the ribbon which extends between the first and second sections. The
locating element is positioned, with the housing located in the recess,
relative to the first and second guide means and relative to the
peripheral surface of the head carrying member, in a manner that when said
first and second guide means engage said first and second sections of the
intermediate ribbon portion and move outwardly to their first and second
operating positions, the locating element restrains outward movement of
the third section of the intermediate ribbon portion so as to maintain
said third ribbon section out of engagement with the peripheral surface of
the head carrying member. This is accomplished in a manner that the
peripheral surface of the head carrying member is engaged by the cleaning
ribbon along an arcuate length of the peripheral surface which is less
than an arcuate length of engagement of the tape when the tape in said
tape cassette is in said operating position extending in a curved path
around the peripheral surface of the head carrying member.
In the preferred embodiment, there are first and second spool means
rotatably mounted to the housing at first and second spool locations to
engage first and second sprockets, respectively, of the machine. The first
and second end portions of the ribbon are connected to the first and
second spool means, respectively.
In the preferred configuration, the locating element comprises a roller
rotatably mounted in the housing so as to engage the cleaning ribbon with
a relatively low frictional engagement.
Also in the preferred form, the cleaning ribbon is a wettable ribbon
adapted to receive a cleaning solution on the ribbon, in a manner that
when the ribbon comes into engagement with the peripheral surface of the
head carrying member, the cleaning solution is able to be applied to the
head carrying member.
In the specific embodiment shown herein, the cleaning apparatus is provided
with means to enable the cleaning ribbon to be wetted at spaced locations
along its length. Thus, the ribbon has alternate wetted and dry locations
along the length of the cleaning ribbon. Specifically, the housing is
provided with opening means enclosing spaced segments of the ribbon. This
permits application of a cleaning solution at said spaced locations by
applying the cleaning solution through the opening means.
In the preferred form, the cleaning ribbon has first and second contact
portions which engage first and second surface portions of the peripheral
surface of the head carrying member. There is a third surface portion of
the peripheral surface of the head carrying member which is out of contact
with the ribbon, this third surface portion being located between the
first and second surface portions and facing the third ribbon section.
Desirably, this third portion of the peripheral surface of the head
carrying member is at least about 1/4th of a circle in arcuate length
around the head carrying member.
Further, each of the first and second contact portions of the cleaning
ribbon engage first and second surface portions of the peripheral surface
of the head carrying member along an arcuate length of the peripheral
surface no greater than approximately 1/8th of a circle.
In the method of the present invention, a cleaning apparatus is provided as
described above. The cleaning apparatus is placed in the recess of the
machine, and the first and second guide means are caused to move outwardly
to bring the cleaning ribbon into cleaning engagement with the peripheral
surface of the head carrying member. The locating element is utilized to
restrain outward movement of the cleaning ribbon in the manner described
above.
Other features of the present invention will become apparent from the
following detailed description.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a plan view of a typical video tape cassette and the operating
components of one type of a video player/recorder for which the present
invention is adapted to be used, with the tape being in its retracted
position in the cassette;
FIG. 2 is a view similar to FIG. 1, illustrating the tape being extracted
from the cassette and in its operating position;
FIG. 3 is a top plan view of a cassette cleaner of the present invention,
shown in its operating position in a cassette receiving recess of a video
player/recorder, and with a portion of the top cover removed for purposes
of illustration, and with the cleaning ribbon in its retracted position;
FIG. 4 is a view similar to FIG. 3, showing the cleaning ribbon extracted
from the cassette cleaner and in its operating or cleaning position;
FIG. 5 is a top plan view similar to FIG. 3, but showing the cassette
cleaner of the present invention in broken lines, and illustrating in full
lines the ribbon tensioning device present in the existing
player/recorder, and with the cleaning ribbon in its retracted position;
FIG. 6 is a view similar to FIG. 5, illustrating the ribbon positioned
outwardly in its cleaning position, and with the tensioning device of the
player/recorder operating to control tension on the ribbon; and
FIG. 7 is a front elevational view taken at line 7--7 of FIG. 3 and
illustrating a retaining element or roller of the cassette cleaner of the
present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention is particularly adapted to clean the operating
components of a video playing/recording unit which is adapted to accept
cassette-type playing tapes, where the tape is extracted by guide members
to be positioned in its playing/recording location in a manner that the
tape extends in approximately a 180.degree. arc around the periphery of
the drum. Further, the tape is positioned so that one set of movable guide
members pulls the tape outwardly from the cassette housing to be
positioned along one side of the drum, while a second set of guide members
pulls the tape outwardly so as to be positioned on an opposite side of the
drum, with the tape extending along the 180.degree. arc between the two
sides. Accordingly, it is believed that a clearer understanding of the
present invention will be obtained by first describing the operating
components of such a conventional video playing/recording unit, and then
describing the present invention. In the following description, the video
playing/recording unit 10 will be referred to as "the video unit" or
simply as "unit".
In FIGS. 1 and 2, some of the main operating components of the video unit
10 are shown in plan view, with a conventional tape cassette also being
shown in plan view in its operating position in the video unit. In the
illustrations of FIGS. 1 and 2, the housing, circuit components, operating
knobs and certain other components of the video unit 10 are not shown,
since these are not required for an understanding of the present
invention.
The tape cassette 12 comprises a case or housing 14 and a magnetic tape 16.
The tape 16 is wound on right and left spools 18 and 20, the tape
extending from one spool 18 to a location 22 at the front left corner of
the case 14, thence along the front edge 24 of the case 14 to the right
front location 26, and thence back to the right spool 20. In FIG. 1, the
tape 16 is shown in its nonplaying or retracted position, and in FIG. 2 in
its operating position.
To describe the operating components of the video unit 10, there are three
magnetic operating components which either respond to the magnetic signals
on the tape 16, affect the magnetic signals on the tape 16, or do both.
These magnetic operating components are: an erase head 28, a drum 30 with
a playing head or element 32, and an audio head 34. The drum 30 has the
general configuration of a circular disc (i.e. a shallow cylinder), and
has a peripheral cylindrically-shaped operating surface 36. The playing
head or element 32 is mounted at the peripheral surface 36 and in this
particular player/recorder, the drum 30 itself rotates about the center
axis 38.
The unit 10 also comprises a number of mechanical components which operate
directly on the tape 16 to properly position the tape 16 in the operating
mode, and also to move the tape 16 along its operating path. First, there
is a capstan 40 and a pinch roller 42. Further, there are guide rollers 44
and 46. Finally, there are six moveable guide members designated 48-58,
respectively. In operation, the guide members 50-58 engage the back side
of the tape 16 and move it outwardly into the playing position shown in
FIG. 2. In this particular unit 10, three of the guide rollers (50-54)
carry the tape 16 outwardly along one side of the drum 30, while two other
guide rollers 56 and 58 carry the tape 16 to the opposite side of the drum
30, with the guide roller 48 performing a locating function.
There is a first drive sprocket 60 which fits into the center portion of
the right spool 20 in a spline fit so that it is able to drive the spool
20. There is a second take-up sprocket 62 which fits through the center of
the left spool 18 in a spline fit. When the tape cassette 12 is initially
placed in the unit 10, the unit 10 is in its nonoperating position, and
the operating components are in the position shown in FIG. 1. When the
unit 10 is placed in its operating mode, the guide members 48-58 move
outwardly to the position of FIG. 2, and the pinch roller 42 moves
rearwardly to press the right hand portion of the tape 16 against the
capstan 40. Also, the drive sprocket 60 rotates the sprocket 20 clockwise
to cause the tape 16 to be wound thereon.
There is a shutoff light 64 which fits in a matching recess formed in the
forward middle portion of the bottom of the case 14. At the forward
portions of the left and right edges of the case 14, there are two
openings 66 and 68, respectively. The unit 10 has a left photocell 70
positioned adjacent the left side of the case 14 and in alignment with the
light 64 and the left opening 66. In some instances, there may be a right
photocell 72 positioned adjacent the right side of the case 14 and in
alignment with the light 64 and the right opening 68. During normal
operation, the photocell 70 (and the photocell 72 if it exists) is
shielded by the tape. However, when the tape 16 travels to its end
position, there is a clear leader portion which permits the light 58 to
activate the photocell 70 (or the photocell 72) to activate the shutoff
mechanism in the unit 10.
It is to be understood that the video player 10, the tape cassette 12 and
the above-described mode of operation of these, already exist in the prior
art.
To describe the present invention, reference is presently made to FIGS. 3
and 4, where a cassette cleaner 74 of the present invention is shown in
its operating position in the video unit 10. As a matter of minor
clarification, the prior art video unit 10 which is shown in FIGS. 3-6 is
of the same basic type as that shown in FIGS. 1 and 2 and already exists
in the prior art, but has some minor differences. The somewhat modified
prior art version of the video unit 10 is shown in FIGS. 3-6 primarily for
convenience of illustration and also for convenience in explaining certain
operating characteristics of such a prior art video unit, and more
specifically, the tape tensioning means of the video unit 10. The specific
structural differences in the unit 10 shown in FIGS. 3-6 will be explained
later herein. However, it's to be understood that the cassette cleaner 74
of the present invention could be used with either of the video units
(i.e. the one shown in FIGS. 1 and 2, or the one in FIGS. 3-6).
The cassette cleaner 74 of the present invention comprises a case or
housing 76 which is or may be substantially similar to the housing 14 of
the conventional tape cassette 12. As shown herein, this housing 76
comprises a front wall portion 78, a rear wall 80, two side walls 82, a
top wall 84 and a bottom wall 86 (a small portion of which is shown in
FIG. 3). Further, the front edge portion of the housing 76 is formed with
two recesses, namely a left recess 88 provided to accommodate the guide
members 50', 52 and 54, and a central forward recess 90, located to
accommodate the two movable guide members 56 and 58.
A cleaning ribbon 92 is mounted in the housing 76 in a manner that a first
left end portion 94 is connected to a left spool 96 and a second right end
portion 98 is connected to a right spool 100. The two spools 96 and 100
are mounted in the housing 76 in generally the same manner and in
generally the same location as the spools 60 and 62 in the conventional
tape cassette 12, so that these spools 96 and 100 engage the drive
spindles 62 and 60 of the player/recorder unit 10.
As shown in FIG. 3, the left end portion 94 of the ribbon 92 extends
forwardly to engage and extend around a locating pin 102 positioned in the
left forward corner of the housing 76. From the pin 102, the ribbon 92
extends at 92a across the forward part of the aforementioned left forward
recess 88. The ribbon 92 then extends from the ribbon portion 92a to
engage the front edge of a left locating wall or abutment 104 and then
moderately rearwardly and to the right to reach behind a locating element
or roller 106 and then extend further to the right and moderately
forwardly to engage a forward edge of a second right abutment or locating
wall 108. This locating roller 106 is particularly critical in the
operation of the present invention, and its function will be discussed
more fully later herein in the description of the operation of the present
invention. That portion of the ribbon 92 extending between the two
abutments or walls 104 and 108 and behind the locating roller 106 is
designated 92b.
The ribbon 92 extends from the ribbon portion 92b further to the right, as
at 92c, to be positioned at the forward portion of the aforementioned
recess 90 and then extends further to the right to a forward end location
adjacent to the capstan 40. The locating of the right forward portion of
the ribbon 92 can be accomplished in a number of ways. In the particular
embodiment shown herein, there is provided a pair of cleaning pads, namely
a first pad 110 positioned to engage and clean the capstan 40, and a
second pad 112 positioned to engage and clean the pinch roller 42. The
cleaning ribbon portion 92c extends from the right locating wall 108 to
engage the forward end of the capstan pad 110, and to extend therefrom at
92d to engage the spool 100. These cleaning pads 110 and 112 can be
mounted and positioned in accordance with teachings presently existing in
the prior art.
The top wall 84 of the housing 76 is provided with a removable circular
cover 114 that fits over the left spool 96. This cover 114 is provided
with a pair of diametrically opposed openings 116 which are positioned to
expose portions of the cleaning ribbon 92. By applying a cleaning fluid
through these openings 116 and onto the ribbon 92, the ribbon 92 becomes
wetted with the solution at spaced locations along the length thereof.
To describe the operation of the present invention, the cleaning ribbon 92
is positioned so that the ribbon 92 is wound a number of times around the
left spool 96 so that several overlapping portions of the ribbon 92 appear
at the openings 116 which are formed in the top cover 114. Further, the
ribbon 92 is positioned so that the forward ribbon portions 92a-c fit
closely against the front edge portion of the housing 76. Then a cleaning
solution is applied through the openings 116 to wet portions of the ribbon
92, this resulting in a wetted pattern of alternate wet and dry portions
of the ribbon 92.
Then the cassette cleaner 74 is inserted into the recess or cavity 118 that
already exists in the player/recorder 10, and which is arranged to receive
the conventional tape cassette 12. This recess 118 is indicated somewhat
schematically in FIGS. 3 and 4 by showing at 120 a portion of the video
unit structure which defines the cassette receiving recess 118. With the
cassette cleaner 74 so positioned, as shown in FIG. 3, the three left
guide members 50', 52 and 54 are po | | |
