Patent Description:
As demands for greater telecommunications access and connectivity speeds increase, so do the demands for greater numbers of fiber optic connections in data centers. Enclosures, racks, and other environments which house such connections must accommodate greater numbers of fiber optic connections, along with the associated cables, fibers, connectors, and other hardware.

Fiber optic cassettes are typically utilized to accommodate fiber optic patch and splice connections. As the need for greater numbers of fiber optic connections and high density fiber optic environments increases, so do the demands for smaller, more compact cassettes which can provide patch and splice features for a large number of fibers and fiber optic connectors. At the same time, such cassettes must be easy to utilize, allowing technicians to easily access the components of such cassettes for patching and splicing purposes. Such easy access in many cases must be facilitated in crowded, high-density data center environments.

Accordingly, improved fiber optic cassettes which address the above concerns are desired in the art. Additionally, improved splice modules which can be utilized with such cassettes would be advantageous.

<CIT> discloses a fiber optic cassette according to the preamble of claim <NUM>. <CIT> discloses a fiber organizer.

The present invention provides a fiber optic cassette according to claim <NUM>.

Optional features of the fiber optic cassette are defined in the dependent claims.

In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope of the appended claims.

Referring now to <FIG>, embodiments of fiber optic cassettes <NUM> and splice modules <NUM> are shown. Fiber optic cassettes <NUM> in accordance with the present disclosure advantageously provide improved patch and splice solutions for high density fiber optic environments. For example, fiber optic cassettes <NUM> in accordance with the present disclosure advantageously provide improved cable routing into the cassettes <NUM>. Further, splice modules <NUM> allow for splicing to be completed outside of the cassettes <NUM> and then moved into the cassettes <NUM>. Further, cassettes <NUM> are relatively more compact and space-efficient than known patch and splice cassettes.

A mutually orthogonal coordinate system is defined for cassette <NUM> in accordance with the present disclosure. The coordinate system includes a longitudinal axis <NUM>, a lateral axis <NUM>, and a transverse axis <NUM>, each of which is mutually orthogonal to the others in the coordinate system.

A cassette <NUM> includes a cassette body <NUM> which defines an interior <NUM>. Body <NUM> extends along the longitudinal axis between a front <NUM> and a rear <NUM>, and extends along the lateral axis between a first side <NUM> and a second side <NUM>, and extends along the transverse axis <NUM> between a bottom <NUM> and a top <NUM>. A base wall <NUM> may be positioned at the bottom <NUM>, and first and second side walls <NUM>, <NUM> may be positioned at the first side <NUM> and second side <NUM>, respectively. A rear wall <NUM> may be positioned at or extend to the rear <NUM>. For example, in exemplary embodiments as shown, the rear wall <NUM> is or includes a curved portion that extends from a position between the front <NUM> and rear <NUM> (in exemplary embodiments more proximate rear <NUM> than front <NUM>) to the rear <NUM>.

Cassette <NUM> further includes a plurality of fiber optic adapter apertures <NUM> defined at the front <NUM>, as shown. Each adapter aperture <NUM> may accommodate one or more fiber optic adapters <NUM> therein. In exemplary embodiments, no fiber optic adapter apertures or adapters are defined in the rear <NUM> or rear wall <NUM>.

Cassette <NUM> may further include a plurality of retention tabs <NUM> disposed in the interior <NUM> of body <NUM>. Retention tabs <NUM> may be positioned above base wall <NUM> to allow fibers within the interior <NUM> to be routed between the retention tabs <NUM> and base wall <NUM>. Retention tabs <NUM> may be advantageously positioned in the interior <NUM> such that fibers can be routed therein without exceeding bending radius limits thereof.

Cassette <NUM> may further include one or more side tabs <NUM>, <NUM>. Side tabs <NUM>, <NUM> may be disposed at the first side <NUM> and second side <NUM>, respectively. For example, side tabs <NUM>, <NUM> may extend from the first side wall <NUM> and second side wall <NUM>, respectively, into the interior <NUM>, such as along the lateral axis <NUM>. As discussed herein, side tabs <NUM>, <NUM> may interface with a cover of the cassette <NUM> to removably connect the cover to the cassette body <NUM>.

Cassette <NUM> further includes a side channel <NUM> defined therein. Side channel <NUM> may, for example, be defined at the first side <NUM>, such as between the rear <NUM> and front <NUM> along the longitudinal axis <NUM>. The side channel <NUM> may extend, such as along the longitudinal axis <NUM>, between an entry aperture <NUM> and an exit aperture <NUM>. The entry aperture <NUM> may provide an entry into the side channel <NUM> from exterior to the cassette <NUM>, and the exit aperture <NUM> may provide an exit from the side channel <NUM> into a remainder of the interior <NUM>. Entry aperture <NUM> is spaced from the rear <NUM>, as shown.

Side channel <NUM> may generally facilitate the entry of fiber optic cables and/or buffer tubes into the cassette <NUM> for splicing and connection purposes. A cable/buffer tube may enter the side channel <NUM> through the entry aperture <NUM> and exit the side channel <NUM> into the remainder of the interior <NUM> through the exit aperture <NUM>. An insert module <NUM> is removably insertable into the side channel <NUM>. The cable/buffer tube may advantageously be insertable into the insert module <NUM>, and the insert module <NUM> and cable/buffer tube then inserted into the side channel <NUM> to secure the cable/buffer tube to the cassette <NUM>.

In some embodiments, the side channel <NUM> may be divided into various portions, such as an entry portion <NUM>, exit portion <NUM>, and intermediate portion <NUM>. Partitions <NUM> may subdivide the side channel <NUM> into such portions. In exemplary embodiments, the insert module <NUM> may be removably insertable into the intermediate portion <NUM>.

Insert module <NUM> may, for example, be formed from a suitably resilient material such as rubber, such as in exemplary embodiments vulcanized rubber. Alternatively, other suitable materials may be utilized. Insert module <NUM> may include a body <NUM> which defines a channel <NUM> in which one or more cables/buffer tubes may be inserted. Channel <NUM> may include one or more channel portions <NUM>', <NUM>". In exemplary embodiments, each channel portion <NUM> may have a generally elliptical cross-sectional profile. When the insert module <NUM> is inserted in the cassette <NUM>, the channel portions <NUM> may be stacked and aligned along the transverse axis <NUM>. Further, each channel portion <NUM>', <NUM>" may have a maximum width <NUM>', <NUM>". In exemplary embodiments, the maximum width <NUM>" may be greater than the maximum width <NUM>'. Further, in exemplary embodiments, channel portion <NUM>' may be above channel portion <NUM>" (e.g. relatively closer to top <NUM>) along the transverse axis <NUM>. Still further, in exemplary embodiments, a portion of body <NUM> may be stacked above the channel <NUM> and channel portions <NUM> thereof, such that the cables/buffer tubes are secured between the body <NUM> and base wall <NUM>.

Cassette <NUM> further includes a splice module receptacle <NUM> defined in the cassette body <NUM>, such as within the interior <NUM>. Receptacle <NUM> may provide a location for removably connecting a splice module <NUM> to the cassette <NUM>. Splice module receptacle <NUM> may, for example, include a frame <NUM> and/or one or more clips <NUM> which removable secure the splice module <NUM> in the interior <NUM>.

As discussed, a splice module <NUM> is provided in a cassette <NUM>. The splice module <NUM> is removably insertable into the splice module receptacle <NUM>. Splice module <NUM> may include a splice insert <NUM>, and may further include a holder base <NUM> and a holder cover <NUM>. The insert <NUM> may, for example, be positionable between the holder base <NUM> and holder cover <NUM>, such that when assembled the insert <NUM> is sandwiched between the holder base <NUM> and holder cover <NUM>. Holder base <NUM> and holder cover <NUM> may be removably connectable to each other, such as via clips <NUM>, <NUM> respectively thereof, to removably secure the insert <NUM> therebetween.

When inserted into a cassette <NUM>, such as the interior <NUM> thereof, a splice module <NUM> may be inserted into and secured within receptacle <NUM>. In some embodiments, for example, module <NUM> may be inserted within the frame <NUM>. In some embodiments, for example, module <NUM> may be secured within receptacle by contact of clips <NUM> with the base <NUM> and/or cover <NUM>.

Splice insert <NUM> may include an insert body <NUM> which includes a first side <NUM> and an opposing second side <NUM>. A plurality of first channels <NUM> may be defined in the insert body <NUM>, such as on the first side <NUM> thereof. One or more second channels <NUM> may be defined in the insert body <NUM>, such as on the second side <NUM> thereof.

Each first channel <NUM> may have a maximum width <NUM>, and each second channel <NUM> may have a maximum width <NUM>. In exemplary embodiments, the maximum width <NUM> of any second channel <NUM> is greater than the maximum width <NUM> of any first channel <NUM>. First channels <NUM> may, for example, be designed to accommodate one or more single splice fibers, while second channels <NUM> may, for example, be designed to accommodate one or more ribbon splices (including for example intermittently bonded ribbon splices).

In exemplary embodiments, the first channels <NUM> and second channel(s) <NUM> may be aligned in a linear array. When the splice module <NUM> is inserted in the cassette <NUM>, the linear array may extend along the lateral axis <NUM>.

In exemplary embodiments, a second channel <NUM> may be positioned between a first portion <NUM> of the first channels <NUM> and a second portion <NUM> of the first channels <NUM>. Each portion may include one or more first channels <NUM>, such as in exemplary embodiments a plurality of first channels <NUM>. In exemplary embodiments, the first portion <NUM> and second portion <NUM> include the same number of first channels <NUM>.

Each first channel <NUM> may include one or more channel portions <NUM>', <NUM>". In exemplary embodiments, each channel portion <NUM> may have a generally elliptical cross-sectional profile. When the splice module <NUM> is inserted in the cassette <NUM>, the channel portions <NUM> may be stacked and aligned along the transverse axis <NUM>. Further, the maximum width <NUM> in each channel portion <NUM>', <NUM>" may in exemplary embodiments be the same. Alternative, the maximum width <NUM> in a channel portion <NUM>' may be different from the maximum width <NUM> of a channel portion <NUM>" in a channel <NUM>.

A cassette <NUM> in accordance with the present disclosure further includes a cover <NUM> which is removably connectable to the cassette body <NUM>, such as at the top <NUM> thereof. When connected, the interior <NUM> may be disposed between the cover <NUM> and base wall <NUM> along the transverse axis <NUM>. Cover <NUM> includes a cover body <NUM> which, when connected to cassette body <NUM>, extends along the longitudinal axis <NUM> between a front <NUM> and a rear <NUM> and extends along the lateral axis <NUM> between a first side <NUM> and a second side <NUM>.

Cover <NUM> further includes a plurality of tabs <NUM> which extend from the front <NUM> along the longitudinal axis <NUM>. When the cover <NUM> is removably connected to the body <NUM>, the tabs <NUM> are removably inserted into the interior <NUM>. More particularly, each of the plurality of tabs <NUM> are removably insertable into one of the plurality of adapter apertures <NUM>. Accordingly, when the cover <NUM> is removably connected to the body <NUM>, the tabs <NUM> are removably inserted into the apertures <NUM>. Tabs <NUM> thus align and secure the cover <NUM> with respect to the body <NUM>.

Cover <NUM> may further include a latch <NUM>, which may be proximate the rear <NUM>. Latch <NUM> may, for example, include a step <NUM>. The latch <NUM>, and in particular the step <NUM> thereof, may contact the body <NUM>, such as the rear wall <NUM> thereof, when the cover <NUM> is removably connected to the cassette body <NUM>. Further, to disconnect the cover <NUM>, a user may need to manipulate the latch <NUM> such that the latch <NUM>, and in particular the step <NUM> thereof, is out of contact with the body <NUM>, such as the rear wall <NUM> thereof. Latch <NUM> thus secures the cover <NUM> to the body <NUM>.

Cover <NUM> may further include one or more side tabs <NUM>, <NUM>. Side tabs <NUM>, <NUM> may be disposed at the first side <NUM> and second side <NUM>, respectively. For example, when cover <NUM> is removably connected to cassette body <NUM>, side tabs <NUM>, <NUM> may extend from the cover body <NUM> into the interior <NUM>, such as along the transverse axis <NUM>.

Each tab <NUM>, <NUM> may interface with a tab <NUM>, <NUM> of cassette body <NUM>, as discussed herein. For example, each tab <NUM>, <NUM> may include a slot <NUM>, <NUM> defined therein. Tabs <NUM>, <NUM> may be removably insertable into the slots <NUM>, <NUM>, respectively, when the cover <NUM> is removably connected to the cassette body <NUM>. Tabs <NUM>, <NUM> may thus align and secure the cover <NUM> with respect to the body <NUM>.

Claim 1:
A fiber optic cassette (<NUM>) defining a mutually orthogonal coordinate system having a longitudinal axis (<NUM>), a lateral axis (<NUM>), and a transverse axis (<NUM>), the fiber optic cassette (<NUM>) comprising:
a cassette body (<NUM>), the cassette body (<NUM>) extending along the longitudinal axis (<NUM>) between a front (<NUM>) and a rear (<NUM>), extending along the lateral axis (<NUM>) between a first side (<NUM>) and a second side (<NUM>), and extending along the transverse axis (<NUM>) between a bottom (<NUM>) and a top (<NUM>);
a plurality of fiber optic adapter apertures (<NUM>) defined at the front (<NUM>) of the cassette body (<NUM>);
a side channel (<NUM>) defined at the first side (<NUM>) of the cassette body (<NUM>), the side channel (<NUM>) comprising an entry aperture (<NUM>) spaced from the rear (<NUM>) of the cassette body (<NUM>) along the longitudinal axis (<NUM>);
a splice module receptacle (<NUM>) defined in the cassette body (<NUM>);
an insert module (<NUM>) removably insertable into an intermediate portion (<NUM>) of the side channel (<NUM>);
a splice module (<NUM>) removably insertable into the splice module receptacle (<NUM>); and
a cover (<NUM>) removably connectable to the cassette body (<NUM>) and comprising a cover body (<NUM>) extending along the longitudinal axis (<NUM>) between a front (<NUM>) and a rear (<NUM>);
characterized in that the cover (<NUM>) further comprises a plurality of tabs (<NUM>) extending from the front (<NUM>) along the longitudinal axis (<NUM>), each of the plurality of tabs (<NUM>) removably insertable into one of the plurality of fiber optic adapter apertures (<NUM>) when the cover (<NUM>) is removably connected to the cassette body (<NUM>).