WO2002091538A1

WO2002091538A1 - Integral cord retraction device for an electric adapter

Info

Publication number: WO2002091538A1
Application number: PCT/US2001/042394
Authority: WO
Inventors: Richard E. Skowronski
Original assignee: Restech, Inc.
Priority date: 2001-05-08
Filing date: 2001-09-28
Publication date: 2002-11-14

Abstract

The combined cord reel and electrical adaptor (10) of the invention comprises a housing (12), a spool (14) rotatably mounted in the housing (10), and an electronic component (22) held in an internal cavity within the spool. A first connector (20) is rigidly mounted to either the spool (14) or housing (10), and is in electrical communication with the electronic component (22). A cable (16) is at least partially carried on the spool (14). One end of the cable (16), preferably the fixed end, is in electrical communication with the electronic component (22). The free end of the cable has a second connector.

Description

INTEGRAL CORD RETRACTION DEVICE

FOR AN ELECTRICAL ADAPTER

FIELD OF THE INVENTION

This invention relates to cord reels and more specifically to

retractable cord reel assemblies for use with electrical adapters for cellular

phones and other electrical devices.

BACKGROUND OF THE INVENTION

Recent advances in electronics have provided the businessman

with a plethora of portable electronic devices such as cellular phones, personal

data assistants ("PDAs"), laptop computers and the like. These products are

highly desirable due to their portability, which is directly related to their size

and weight.

Battery technology has not kept pace with these advances,

forcing the businessperson to bring his AC adapters or battery chargers along with him to work, to meetings or while traveling. Typically, the batteries in a

PDA or a cellular phone will power the unit only for a few hours of continuous

use, which is inadequate for the normal businessperson. Manufacturers prefer

smaller batteries because they allow them to market smaller, more desirable

products, but power capacity in the form of battery life is sacrificed. As a

result, users of these devices take their battery chargers or electrical adapters

with them wherever they go and connect to high voltage power whenever

possible.

Little effort has been allotted to improving the portability of the

electrical adapters. The cords attached to these adapters are usually randomly

coiled by hand around the adapter housing, hindering its portability and often

resulting in tangled and/or damaged cords. If a coiled cord is placed on a table

or in a briefcase, it begins to uncoil as soon as it is released. The lack of

portability is very much incongruous with the excellent portability of the

devices they power.

A common power adapter has a square or rectangular housing

containing electrical components such as a transformer and/or power

conditioning electronics. Protruding from the housing are male contacts for

engagement with an electrical receptacle. When the adapter is inserted into the

wall outlet, the housing bears against the wall, hanging by the plug. A low

voltage cord is connected to this power adapter for connection to a

rechargeable product, such as a cellular phone. When the businessperson

travels, the adapter is unplugged from the wall receptacle, the cord is randomly coiled around the power adapter housing as it is packed into a briefcase or

suitcase.

Prior art references disclose the use of cord reels to take up

excess cable in a variety of uses. U. S. Patent No. 3,773,987 to Davis discloses

an electrical cable retractor with an integral male connector. The spool rotates

with respect to both the housing and the electrical connector, requiring a

mechanism that maintains an electrical circuit connection between the inner

end of the cable and the electrical connector during the winding and unwinding

of the cable. See also U. S. Patent No. 5,094,396 to Burke showing the use of a

cord reel for storage of a telephone cord.

Wagner, in U. S. Patent No. 5,590,749, describes a telephone jack

extension where the spool rotates about the low voltage jack. It utilizes

electrically conducting contact brushes and conductive rings to carry the

electrical signal as the spool rotates. A circuit board may be used to distribute

the signal over the conducting rings, however, the electrical signal is not

modified in any way.

Whereas the prior art discloses retractable cord reels, and

whereas power adapters and other devices that modify electrical signals are

known in the art, heretofore, there has been no known teachings on how to

combine a cord reel with an electrical adapter.

It is therefore an object of this invention to provide an improved

electrical adapter with an integrated cord reel that allows direct electrical

connection between a power source and an electrical device. It is another object of this invention to provide an improved

electrical adapter with an integrated cord reel that minimizes space.

It is yet another object of this invention to provide an improved

electrical adapter with an integrated cord reel that easily stores and protects the

accompanying cable in a convenient and useful manner.

SUMMARY OF THE INVENTION

These and other objects are met or exceeded by the present

invention, which features a combined cord reel for an electrical adapter.

The combined cord reel and electrical adapter of the invention

comprises a housing, a spool rotatably mounted in the housing, and an

electronic component held in an internal cavity within the spool. A first

connector is rigidly mounted to either the spool or housing, and is in electrical

communication with the electronic component. A cable is at least partially

carried on the spool. One end of the cable, preferably the fixed end, is in

electrical communication with the electronic component. The free end of the

cable has a second connector.

In a preferred application of the invention, the electrical adapter

is a power transformer that converts household current to low voltage direct

current for a cellular telephone other electronic device. The retractable cable is

extended from the spool, and the second connector is connected to the cellular

phone. The first connector is a conventional plug adapted for connection to a standard outlet. After the telephone has been charged, the cord may be

retracted back into the housing by rotating the spool.

A first preferred embodiment of the present invention provides a

combination cord reel and an electrical adapter that includes a first connector

fixedly mounted to the spool. The electronic component is held within the

interior cavity of the spool.

In a second preferred embodiment of the invention, the first

electrical connector is on the housing and is in electrical communication with

the fixed end of the cable through the electronic component. A rotation

translator allows for electrical communication as there is relative rotational

movement between the first connector and the electronic component. The

rotation translator may be a captive cable or electrical wiping contacts.

In both embodiments, the electronic component changes at least

one property of the electrical communication, e.g. a transformer or converter.

Optionally, a portion of the spool acts as a knob that projects through an

opening in the housing, and is hollow to extend the volume of the interior

cavity. A preferred embodiment for use with a cellular phone has a transformer

installed in the interior cavity that outputs low voltage power to the cable.

The combination cord reel and electrical adapter of the present

invention includes a cord reel for the convenient storage of the cable. Instead

of hastily wrapping the cable around the adapter housing, the cord reel provides

a storage space for the cable. The cable is neatly coiled inside the housing,

where the cable will not unwind when released. Further, the housing provides protection for the cable. Use of the cord reel provides an area for smooth,

continuous winding of the cable. The cables are less likely to be damaged.

The housing also protects the cable from bumps, cuts and other hazards.

The combined adapter and cord reel are also designed to conserve

space. The electronic components are stored in the hub of the spool, or the

interior space in an optional knob on the top portion of the spool, or a

combination thereof. The knob is suitable for manually turning the spool to

retract the cable, as well as providing space to house the electronic

components.

In a preferred embodiment, several additional features are

present. A portion of the spool preferably protrudes through an opening in the

housing, providing additional interior space for the electrical adapter or other

electronic components. Also, it is preferred for the first connector to mount

directly to the spool so that there is no relative motion between the first

connector and the spool. Most preferably, the adapter is a transformer designed

for a cellular phone and the cable is a low voltage cable with a low voltage

connector.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top plan view of a first embodiment of the

combination cord reel and electrical adapter of the invention;

FIG. 2 is an end view thereof; FIG. 3 is a side view thereof;

FIG. 4 is a bottom perspective view thereof;

FIG. 5 shows an exploded side view thereof;

FIG. 6 is a cross section taken along lines 6-6 of FIG 1 ;

FIG. 7 is a top plan view of a second embodiment of the

combination cord reel and electrical adapter of the invention;

FIG. 8 is a bottom plan view of second embodiment;

FIG. 9 is a side view of the second embodiment;

FIG. 10 is a cross-sectional view taken along line 10-10 of FIG.

9;

FIG. 11 is a cross-sectional view of the adapter of FIG. 7 taken

along line 11-11 of FIG. 9; and

FIG. 12 is a cross-sectional view taken along line 12-12 of FIG.

7.

DETAILED DESCRIPTION OF THE INVENTION

A first preferred embodiment of a combination cord reel and

electrical adapter, generally 10, is shown in FIGs. 1-6. The electrical adapter

10 is used to provide an electrical communication from a source to an

electronic device, and to convert, transform or otherwise adapt the source

signal for the electronic device. As shown, the electrical adapter 10 may find particular use as a power adapter for a cellular phone. The apparatus of the

invention may find numerous other uses, e.g., a power adapter for a portable

computing device. It is understood that the adapter shown in the drawings and

the uses of this device described herein are intended to be illustrative of the

invention only, and not limiting in any way.

Referring to the drawings, the electrical adapter 10 comprises a

housing 12. Contained at least partially within the housing are a cord reel or

spool 14, a cord or retractable cable 16, a first electrical connector 20 and an

electronic component 22. Any material is suitable for manufacturer of the

housing 12, if it is lightweight, durable and inexpensive. When used with

portable devices, weight is important, as it is undesirable for the user to become

bogged down with heavy equipment. Transport of the electrical adapter 10

with the electronic device leads to packing of the electrical adapter 10 in

suitcases, computer cases or briefcases. During transportation, the contents of

the case may shift, causing the adapter to be thrown against the walls of the

case or other objects. The suitable material from which the housing 12 is

constructed should be able to withstand the normal bumps and bruises that are

likely to occur in such situations. Finally, the housing 12 is also made of a

material that is relatively inexpensive to fabricate or mold. Plastics are the

most preferred housing material because they fit all three of these criteria.

Metals, such as aluminum, are useful but not preferred because they are

generally more expensive. The spool 14 is rotatably mounted on and at least partially held in

the housing 12. The housing 12 on one face has a circular opening 36 through

which a knob 42 portion of spool 14 extends. The opposite face of housing 12

has a circular opening 37 through which a circular portion 62 of spool 14

extends. Accordingly, spool 14 is free to rotate relative to the housing 12 with

openings 36, 37 forming bearing surfaces with spool portions 42 and 62,

respectively.

Electrical communication is maintained from the first connector

20 through the electronic component 22 to the fixed end 64 of the cable 16.

Communication is facilitated by close proximity between the three parts. Lack

of motion between the first connector 20 and the spool 14 allows for direct

connections between the first connector 20 and the electronic component 22

and from the electrical component 22 to the cable 16. Direct electrical

connections between these parts are preferred.

Spool 14 and cable 16 are held within at least a portion of the

housing 12. Cable 16 is at least partially carried by the spool 14. There is a

cavity 30 within a hub 34 of the spool 14 holding and storing the electronic

component 22. A portion of the spool 14 optionally protrudes through the

opening 36 in the housing 12, forming the knob 42 that is easily gripped for

manual rotation of the spool 14 within the housing 12. The knob 42 can be of

unitary construction with the spool 14, or, the spool can be assembled from the

base 40 and the knob 42. The first connector 20 is mounted to the spool 14. Preferably the

connector 20 is mounted to a base 40 of the spool 14 as shown in FIG. 2.

However, the connector can be mounted anywhere on the spool, such as on the

knob 42.

The electronic component 22 is sized and adapted to fit the cavity

30 of the spool 14. In the case of a cellular phone, component 22 may

comprise a transformer to convert 110VAC to low voltage direct current.

However, depending on the application, the electronic component 22 is suitable

as long as it changes the properties of the electrical communication between the

first connector 20 and the cable 16, and may comprise a switch, a transformer,

a voltage regulator, an electrical converter, battery charger or the like. The

specific nature of the electronic component 22 is limited only by its size and

usefulness with a portable electrical adapter 10.

Electricity flows through electrical adapter 10 between the first

connector 20, the electronic component 22, cable 16 and a second connector

26. Direction of the electricity flow is not important to the invention, and will

depend entirely upon the specific use of the electrical adapter 10. The use to

which the electrical adapter 10 is to be put also determines the choice of the

first and second connectors 20, 26. Any connectors are useful with the

invention such as low or high voltage power plugs, telephone, modem or

network connectors and the like. In the illustrated embodiments, the second

connector 26 is a low voltage connector such as those used to charge batteries

or supply power to battery driven electronic devices. In the first embodiment, the first connector 20 is a male plug

suitable for use with a common electrical receptacle or outlet. The first

connector 20 may be connected to the electrical adapter 10 in various ways. It

is preferably fixedly mounted to the electrical adapter 10, but may also be

connected via a separate, short cable or be attached to a second full length cable

co- wound with the cable 16 on the spool 14. Use of a cord reel assembly with

multiple cords co-wound on the same spool 14 is taught in PCT Application

US01/03368 to Skowronski, herein incorporated by reference.

In the first embodiment, the first connector 20 is attached to the

spool 14 of the electrical adapter 10. When the first connector 20 is located on

the spool 14, there is no relative motion between the spool and the connector so

that a direct connection between the connector and the electronic component 22

can be made. This technique is preferred because it results in less expensive

and more compact adapter 10.

The housing preferably has a pocket or chamber 24 for storing

the second connector 26 when not in use, as seen in FIGs. 2 and 4. The second

connector 26 can be molded onto the cable 16 as an integral part of it. The

connector 26 neatly fits into the chamber 24. In this embodiment, the storage

chamber 24 for the second connector 26 is located along the path followed by

the cable 16 as it is retracted into the housing 12. The connector 26 is drawn

into the housing 12 and into the storage chamber 26 without separate handling

by the user. In the alternative, the chamber 26 is optionally located to one side

of the path followed by the cable 16. Following retraction, the connector 26 is manually fit into the chamber 24 for storage. Alternately, if there is no

chamber 26, the second connector 26 can be left hanging on the outside of the

housing 12.

An optional window 25 in the side of the housing 12 allows

access to the second connector 26 when the cable 16 is fully retracted into the

housing. A lever, button, slide or other mechanism (not shown) may also be

employed to push or pull the second connector 26 out of the housing 12. A

stop bar 28, shown in FIG. 5, is optionally used to block inward movement of

the second connector 26 after it is retracted into the housing 12. This keeps it

in the proper place where it is conveniently accessed by the user. Where it is

not desirable to store the second connector 26 inside the housing, the stop bar

28 prevents the second connector from being retracted too far into the housing

12.

Preferably, the knob 42 is designed as a separate unit and affixed

to the base 40 after installation of the electronic component 22. The knob 42 is

preferably designed to extend the cavity 30, allowing additional room to

accommodate the electronic component 22. In the most preferred arrangement

for the spool 14, a base 40 has at least one rim 46 and at least one cord winding

surface 48. The knob 42 includes at least a second rim 50 and a gripping

surface 54. Preferably, the second rim 50 extends outward from the gripping

surface, leaving a hollow space 56 inside the knob 42 for extension of the

cavity 30. After installation of the component 22, the knob 42 is attached to

the base 40 forming the spool 14 with the hub 34 and at least two rims 46, 50. In another optional arrangement, the cord winding surface 48 is at the center of

the spool 14, such that no cavity 30 exists at the hub 34 of the spool. In this

arrangement, the electronic component 22 is located entirely in cavity 30 of the

knob 42.

The gripping surface 54 optionally has a finger guide 60 to act as

an indexing feature when aligning the first connector 20 with the receptacle. It

is often difficult to see the how the connector 20 aligns with the receptacle

while the electrcial adapter 10 is close to the receptacle when trying to mate

them. Having visible and tactile feedback as to the position of the connectors

20 improves the ease of inserting the connector into the receptacle. The guide

60 may also assist gripping of the knob 42, providing a flat surface on which to

rest a thumb or finger.

The knob 42 is shown as being round, however, alternate

configurations may be used as desired to achieve the volume required to house

the electronics and the desired aesthetics. For example the electronic

component 22 could be configured to fit partially or entirely within the hub 34

or entirely in the knob 42 of the spool 14. Preferably, the overall size of the

unit is minimized to enhance portability.

The fixed end 64 of the cable 16 is connected to the electronic

component 22 at or near the hub 34 of the spool 14. Preferably, the cable 16 is

routed through an opening 66 on the cord winding surface 48 of the hub 34 for

connection to the electronic component 22. A free end 68 of the cable 16 is

preferably fitted with the second connector 26. The type of cable 16 and the second connector 26 used with the present invention are selected by suitability

for the particular application for which the electrical adapter 10 is intended to

be used. For use with a cellular phone, for example, a low voltage mini-plug is

one of the appropriate second connectors 26. Many other types of electrical

cables 16 or second connectors 26 are also suitable for various applications.

In the preferred configuration, the cord reel housing 12 also has

cable guides and or rollers 70, shown in FIG. 5, to guide the cable 16 into its

stored position so that the windings of cable lie neatly together to minimize

space as they are wound on the spool 14. The cable 16 is fed between a

plurality of cord guides 70, or a single guide and another stationary element,

such as the housing 12, preventing tangled portions of the cable from entering

the housing 12 and possibly becoming lodged inside the electrical adapter 10.

A friction device 72 between the spool 14 and housing 12 is

optionally used to prevent the cable 16 from unwinding at inopportune times.

When the cable is retracted, if there is very little friction between the spool 14

and the housing 12, the spool may tend to partially unwind, for example, as a

result of the elasticity of the polymer insulation being bent as it wraps around

the spool during the winding process. A friction device minimizes any

unwinding tendency after the winding is complete, or between turns of a

manually wound unit. Friction devices, such as wave washers or friction

washers, are well known in the art. A preferred friction device 72 is optionally

molded into the cord reel housing 12, eliminating the need for additional parts.

Slots 74 are preferably molded into the housing 12, forming a leaf spring 76 ι between each adjacent pairs of slots. A portion of the leaf spring 76 protrudes

toward and biases against the spool 14 pressing against the spool to cause

friction between spring 76 and the spool rim 46.

A second embodiment of the electrical adapter, generally 110, is

shown in FIGs 7-12. Unless specifically noted, parts corresponding to the

second embodiment of an electrical adapter 110 have the same numbers and

features and properties as the first embodiment 10 discussed above, but in the

100 sequence. In the second embodiment, the first connector 120 is preferably

mounted to the housing 112.

The electrical adapter 110 includes a housing 112 in which the

spool 114 is rotatably mounted. When the connector 120 is fixedly mounted to

the housing 112, but the electronic component 122 and the cable 116 rotate

with the spool 114, the housing 112 also carries a rotation translator 118 for

electrically accommodating the relative motion of the first connector 120 and

the electronic component 122. Two common methods of making this

accommodation are through the use of a captive cable, such as that taught in U.

S. Patent No. 3,773,987 to Davis, herein incorporated by reference, U. S. Patent

No. 5,094,396 to Burke, herein incorporated by reference, or by using

conducting brushes as taught in U. S. Patent No. 5,590,749 to Wagner, herein

incorporated by reference. Incorporation of a spring into the retraction

mechanism, also contemplated as being used in this invention, is also taught in

the above-referenced patents. Use of the captive cable 118 is discussed further by way of an example only, and is not intended to limit the scope of the

invention.

When the captive cable 118 is used to accommodate the rotation

of the spool 114, the captive cable is held in a captive cable compartment 119

of the spool 114. Compartment 119 is preferably on the side of the spool

adjacent the first connector 120 to facilitate connection between connector 120

and adapter 122. A first end 121 of captive cable 118 is electrically connected

to the first connector 120, and the second end 123 of the captive cable is

connected to the electronic component 122. The spool 114 preferably has an

interior wall 129 that separates captive cable 118 from retractable cable 116.

During winding or unwinding of the retractable cable 116, the

captive cable 118 is coiled or uncoiled allowing it to maintain electrical

communication without becoming tangled. The second end 123 of the captive

cable 118 enters the hub 134 of the spool 114 axially through or near the axis

of rotation of the spool. As the cable 116 is wound into the spool 114, the

captive cable 118 is wound tightly in the center of the compartment 119.

Unwinding of the retractable cable 116 uncoils the captive cable 118 within

compartment 119. Whether the captive cable 118 coils or uncoils during the

winding of the retractable cable 116 is unimportant, and is easily controlled by

merely specifying the direction in which captive cable 118 coils when it is

installed.

The adapter of the second embodiment of the invention allows

extension or extraction of the cable 116 onto and off of the spool 114 while the first connector 120 is connected to a wall receptacle. It is particularly

convenient for those who routinely recharge their electronic device in the same

location and like to leave the electrical adapter 100 plugged into the wall.

During operation, the free end 168 of the cable 116 is pulled to unwind the

cable. The spool 114 rotates within the housing 112 to allow the cable 116 to

unwind. While the spool 114 is turning, the captive cable 118 uncoils and the

housing 112 is stationary. The process is reversed when the retractable cable

116 is withdrawn onto the spool 114.

With the first electrical connector 120 attached to the housing

112, use of the finger guide is less important. Since the first connector 120

does not rotate with the spool 114, the finger guide is not required for aligning

the first connector 120 with the corresponding receptacle. However, the finger

guide remains useful as a means of getting a better hold of the gripping surface

154.

The remaining features of the first embodiment 10 are equally

applicable to the second embodiment of the electronic device 100 and serve the

same functions. Accordingly, the combination cord reel and electrical adapter

of the invention is a compact device that conveniently stores a retractable cable

inside the housing. It can also house an electronic components compactly

within the hub 134 of the spool 114. It provides a facile solution to

longstanding problems in the art.

While a particular embodiments of the present invention have

been shown and described, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the

invention in its broader aspects and as set forth in the following claims.

Claims

What is claimed is:

1. An integral cord reel for an electrcial adapter comprising:

a housing;

a spool, rotatably mounted at least partly in said housing;

a cable, at least partly carried by said spool, having a fixed end

and a free end;

a first electrical connector; and

an electronic component carried by said spool and in electrical

communication with said fixed end of said cable and said first electrical

connector.

2. The electrical adapter of claim 1, wherein said electronic

component is a transformer.

3. The electrical adapter of claim 1 wherein said spool

further comprises a base and a knob.

4. The electrical adapter of claim 1, wherein said first

connector is a power plug.

5. The electrical adapter of claim 3, wherein said electronic

component is housed in an interior cavity of said spool.

6. The electrcial adapter of claim 3, wherein at least a portion

of said knob protrudes through an opening in said housing.

7. The electrcial adapter of claim 1, wherein said spool

comprises at least two rims, a cord winding surface therebetween and a knob

having a gripping surface.

8. The electrcial adapter of claim 3 wherein said knob

includes a finger guide.

9. A combination cord reel and electrical adapter comprising:

a housing;

a spool rotatably mounted to said housing, having an interior

cavity;

at least one cable at least partly carried by said spool, having a

fixed end and a free end;

a first connector fixedly mounted to said spool; and

an electronic component in said interior cavity of said spool in

electrical communication between said first connector and said fixed end of

said cable.

10. The electrical adapter of claim 9, wherein said first

connector comprises a power plug.

11. The electrical adapter of claim 9, wherein said electronic

component comprises a transformer.

12. The electrical adapter of claim 9, wherein said spool

comprises a base and a knob.

13. The electrical adapter of claim 12, wherein said first

connector is mounted to said base.

14. The electrical adapter of claim 12, wherein said knob

further comprises a finger guide.

15. The electrical adapter of claim 9, wherein said spool

comprises two rims and a cord winding surface therebetween, and a knob

having a gripping surface.

16. The electrical adapter of claim 12, wherein at least a

portion of said knob projects through an opening in said housing.

17. An integral cord reel and electrcial adapter comprising: a housing;

a spool, rotatably mounted at least partly in said housing;

a cable, at least partly carried by said spool, having a fixed end

and a free end;

a first electrical connector mounted to said housing;

a rotational translator at least partly mounted to said spool; and

an electronic component carried by said spool and in electrical

communication with said fixed end of said cable and said first electrical

connector.

18. The electrical adapter of claim 17, wherein said spool

further comprises a base and a knob.

19. The electrcial adapter of claim 18, wherein said rotational

translator is a captive cable at least partially stored in said base.

20. The electronic device electrcial adapter of claim 18,

wherein at least a portion of said knob projects through an opening in said

housing.