US20050272401A1 - Environmentally-sealed portable terminal - Google Patents

A wearable, mobile and/or portable terminal for use in an inventory management system. The terminal includes a terminal housing, a battery pack removably receivable within an external battery-receiving cavity of the terminal housing, and a battery latching mechanism that secures the battery pack in the battery-receiving cavity in a latched condition. The battery pack has an unlatched condition in which the battery latch mechanism is disengaged from the battery pack. The terminal and battery pack are environmentally sealed to, for example, preclude entry of water into the interior of the terminal when the terminal is immersed.

CROSS REFERENCE TO RELATED APPLICATIONS

• This application is a divisional of application Ser. No. 10/185,334, filed Jun. 27, 2002, the disclosure of which is hereby incorporated by reference herein in its entirety.

FIELD OF THE INVENTION

• This invention relates generally to wearable, portable and/or mobile computer terminals and peripherals.

BACKGROUND OF THE INVENTION

• Wearable, portable and/or mobile computer terminals are used for a wide variety of tasks. Such terminals allow a worker using them to have mobility, while providing them with desirable computing and data-processing functions. Furthermore, various terminals provide a communication link to a larger, more centralized computer system. Such terminals are being implemented for an ever-increasing number of tasks.

• One illustrative example of a specific use for a wearable or portable terminal is inventory management. Computerized inventory management systems are used in inventory-driven industries for various tasks, such as food and retail product distribution, manufacturing, and quality control. An overall integrated inventory management system involves a combination of a central computer for tracking and management, and the people who use and interface with the computer system in the form of order fillers, pickers and other workers. The workers handle the manual aspects of the integrated management system.

• To provide an interface between the central computer system and the workers, wearable or portable terminals are used by the workers as they complete their numerous tasks. Such wearable terminals, for example, pull information directly from the central system and translate the information into voice or text commands for the workers. Through wireless RF networks, the commands to and responses from the workers are communicated between the system and the terminals. To communicate in a voice driven system, for example, the worker wears a headset which is coupled to their wearable terminal. Through the headset, the workers are able to receive voice instructions, ask questions, report the progress of their tasks, and report working conditions, such as inventory shortages, for example. Using such terminals, the work is done virtually hands-free without equipment to juggle or paperwork to carry around.

• In addition to headsets, other peripherals are often coupled to the terminals depending upon the tasks to be performed. For example, bar code readers and other scanners may be utilized alone or in combination with a headset to communicate back and forth with the system.

• An illustrative example of a job through a system utilizing wearable and/or portable terminals having voice capabilities may involve initially welcoming the worker to the system and defining a particular task or order, for example, a load to be filled for a certain truck to depart from a warehouse. The worker may then answer with a particular area (e.g., freezer) that they will be working in for that order. The system then vocally directs the worker to a particular aisle and bin to pick a particular quantity of an item. The worker then vocally confirms their location and the amount of items that are picked. The system may then direct them to a loading dock or bay for a particular truck to receive the order. As may be appreciated, various different scenarios might be played out through the system using a wearable terminal and attached peripherals.

• The terminals are electronic devices which require a source of power. Therefore, they utilize a portable power source, such as a battery. During a shift, a worker may find that they must replace the battery in their terminal with a new one. This can be a tedious task. Often times a worker will have to stop what they are doing, remove the terminal from their belt or other securing device, disconnect the battery and install/connect a new battery. This usually requires two hands and is a significant disruption to the work schedule.

• A further issue with portable batteries used with wearable and/or portable terminals is that they are susceptible to falling off or out of the terminal during use. As may be appreciated, wearable terminals are subject to rigorous use as the workers scramble around handling various tasks. The terminals are often bumped or otherwise abused in use.

• In the past, batteries have tended to fall off when the terminals or the batteries were bumped. This might cause the battery or its casing to break, particularly on hard, concrete floors, and thereby result in further delays for the worker.

• An additional concern with wearable terminals and also the power supplies therein, is their exposure to harsh environments which may affect their operation. Specifically, many work environments expose the terminals, and therefore the batteries, to moisture. Sometimes such moisture is direct, however, it is often in the form of condensation which may find a pathway into the electrical components of the terminal and also to the battery. For example, in food distribution, the terminals are exposed to the cold of a refrigerator or freezer environment, and then to the ambient warmth or heat and humidity of the rest of the facility. The moisture and condensation may cause electrical shorts and malfunctions in the terminal and in the batteries.

• As such, it is desirable to improve upon the ruggedness of wearable terminals and their power sources. It is also desirable to improve the battery management procedures for active workers and reduce delays associated with power issues. It is further desirable to make workers more efficient and effective.

BRIEF DESCRIPTION OF THE DRAWINGS

• The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the principles of the invention.

• FIG. 1

  is an illustration of a terminal constructed in accordance with the principles of the invention;

• FIG. 2

  is a partially-broken away side view of the terminal of

  FIG. 1

  showing the battery pack in a latched condition;

• FIG. 3

  is a partially-broken away side view of the terminal of

  FIG. 1

  showing the battery pack in an intermediate condition;

• FIG. 4

  is a partially-broken away side view of the terminal of

  FIG. 1

  showing the battery pack in an unlatched condition;

• FIG. 5

  is an exploded view of a portion of the terminal of

  FIG. 1

  showing the assembly of the battery latch mechanism with the terminal housing; and

• FIG. 5A

  is an exploded view of the battery latch mechanism of the terminal of

  FIG. 1

  .

DETAILED DESCRIPTION

• Although the invention will be described next in connection with certain embodiments, the invention is not limited to practice in any one specific type of wearable, portable and/or mobile terminal. It is contemplated that the principles of the invention can be used with a variety of electronic devices, including but not limited to wearable terminals for use with computerized inventory systems. The description of the invention is intended to cover all alternatives, modifications, and equivalent arrangements as may be included within the spirit and scope of the invention as defined by the appended claims. In particular, those skilled in the art will recognize that the components of the invention described herein could be arranged in multiple different ways.

• With reference to

  FIG. 1

  , a wearable, portable and/or

  mobile terminal

  10 of the invention is worn by a worker on a

  belt

  12 or is otherwise associated by another securing device associated with the worker's person. The

  terminal

  10 is connected to at least one

  peripheral device

  14, such as a headset or bar code reader, by a length of a

  cord

  16 electrically coupled to the

  terminal

  10. Alternatively, each

  peripheral device

  14 may communicate unidirectionally or bidirectionally with the

  terminal

  10 over a wireless communication link, such as a radiofrequency (RF) link or an infrared (IR) link.

• Such terminals

  10 may be used, for example, in warehouse environments where workers are required to retrieve various items within the warehouse. An interior 17 of the terminal 10 houses electronics including a transceiver (not shown) that communicates with a remote central computer by transmitting and receiving information regarding the activities performed by the worker.

• For use in a warehouse environment, the terminal 10 incorporates a

  removable battery pack

  18 and a

  battery latch mechanism

  20 for detachably securing the

  removable battery pack

  18 to the terminal 10. The

  battery pack

  18 supplies electrical power to the electronics of the terminal 10 so that the terminal 10 is wearable by the worker and is portable. As the

  battery pack

  18 is powered and used in the warehouse environment, the electrical energy stored by the

  battery pack

  18 is necessarily depleted until the battery capacity is expended. The battery capacity of the

  battery pack

  18 may be replenished with a battery charger (not shown) having a power supply that can provide a supply of DC current.

• With reference to

  FIGS. 2 and 5

  , the terminal 10 includes a

  terminal housing

  22 having a curved, convex

  outer surface

  23 and a battery-receiving

  cavity

  24 recessed below the

  outer surface

  23. The battery-receiving

  cavity

  24 is dimensioned to receive the

  battery pack

  18 therein and provides a recessed void generally shaped like a cuboid or a parallelepiped that is external to the

  terminal housing

  22. The

  terminal housing

  22 includes a pair of opposing

  side walls

  25, 26, a pair of opposing

  end walls

  27, 28, and a

  base wall

  30 having an outwardly-facing substantially planar,

  rectangular base surface

  32 extending transversely between the

  side walls

  25, 26 and longitudinally between the

  end walls

  27, 28. The

  walls

  25, 26, 27, 28 and 30 defined the boundaries of the battery-receiving

  cavity

  24.

  End wall

  28 separates a

  chamber

  38 provided inside the

  terminal housing

  22 from the battery-receiving

  cavity

  24. The

  terminal housing

  22 may be molded from a polymer resin. As used herein, inwardly and outwardly directions are referenced relative to the

  base surface

  32 bounding the battery-receiving

  cavity

  24. An outwardly direction is directed away from the

  base surface

  32 and an inwardly direction is directed toward the

  base surface

  32.

• A plurality of spring-loaded

  electrical contacts

  34, of which one

  electrical contact

  34 is shown in

  FIG. 2

  , are located within the

  terminal housing

  22 and positioned opposite to the location of the

  battery latch mechanism

  20. Each electrical contact includes a

  tang portion

  36 disposed within the

  chamber

  38 and a

  spring finger

  40 projecting into the battery-receiving

  cavity

  24 from a corresponding one of

  multiple openings

  42

  penetrating end wall

  28. Each

  spring finger

  40 is resiliently deflectable by a force applied in a direction generally toward the

  end wall

  28 with a concomitant storage of elastic energy. A

  lip portion

  44 of the

  terminal housing

  22 projects outwardly from

  end wall

  28 over a portion of the battery-receiving

  cavity

  24 so as to overhang the

  spring fingers

  40. Each

  tang portion

  36 is coupled electrically by an

  individual conductor

  39 with the electronics housed within the

  terminal housing

  22.

• An

  encapsulant

  46, such as an encapsulant selected from among the 1650 Series of encapsulants commercially available from Mereco Technologies Group (West Warwick, R.I.), is injected into the

  chamber

  38 to secure the

  electrical contacts

  34 in place and to prevent displacing of the

  electrical contacts

  34 by the

  battery pack

  18 relative to the battery-receiving

  cavity

  24 back into the

  terminal housing

  22. In one aspect of the invention, the

  encapsulant

  46 also provides waterproofing and dustproofing so that the terminal 10 is sealed against the entry or infiltration of contaminants, including dust, moisture and other liquids, into the interior 17 of the

  terminal housing

  22 through

  openings

  42. The battery-receiving

  cavity

  24 is accessible from the exterior of the

  terminal housing

  22 for placement of the

  battery pack

  18. As a result, the

  terminal housing

  22 is sealed from the ambient environment of the terminal 10 and the

  battery pack

  18 can be positioned within the battery-receiving

  cavity

  24 without exposing the interior 17 of the terminal housing to the ambient environment. In addition, the sealed nature of the

  terminal housing

  22 permits the terminal 10 to operate in ambient environments entailing exposure to condensation, moisture and other liquids without a significant risk of damage to the electronics housed inside the

  terminal housing

  22.

• In certain embodiments, the environmental-sealing of

  terminal housing

  22 may comply with the IP67 standard of the International Protection (IP) rating system which requires that the

  housing

  22 be dust proof and that the

  housing

  22 prevent the entry of water into the interior 17 if immersed in room temperature water to a depth of 1 meter for 30 minutes. The International Electrotechnical Commission standardizes classes of environmental protection for industrial equipment using the IP rating system.

• With reference to

  FIG. 2

  , the

  battery pack

  18 includes a sealed

  case

  48, preferably molded from a polymer resin and shaped roughly like a parallelepiped or cuboid, and a

  battery cell

  47, typically a lithium ion battery cell, housed within the sealed environment of the sealed

  case

  48. The sealed

  case

  48 is provided with a pair of opposing transverse ends 50, 52, a

  peripheral edge

  53 at

  transverse end

  52, a contact-containing

  portion

  54 protruding outwardly from

  transverse end

  50, and an outwardly-facing

  shoulder

  56 formed by the contact-containing

  portion

  54. A convex outwardly-facing

  surface

  58 of the sealed

  case

  48 has a curvature that conforms with the curvature of the

  outer surface

  23 of the

  terminal housing

  22 when the

  battery pack

  18 is inserted in the battery-receiving

  cavity

  24. An inwardly-facing

  planar surface

  60 of the

  battery pack

  18 provides a substantially abutting contact with the

  planar base surface

  32 of the battery-receiving

  cavity

  24 when the

  battery pack

  18 is inserted into battery-receiving

  cavity

  24.

• A set of cylindrical

  conductive contacts

  62, of which one

  electrical contact

  62 is visible in

  FIG. 2

  , is disposed in the contact-containing

  portion

  54 of the sealed

  case

  48 of

  battery pack

  18. Each of the

  conductive contacts

  62 is terminated by a disk-shaped

  flat pad

  64 facing outwardly from

  transverse end

  50. The set of

  conductive contacts

  62 participates in electrically coupling the battery cell with the electronics disposed within the

  terminal housing

  22 of the terminal 10. To that end, each

  flat pad

  64 of the

  battery pack

  18 is electrically coupled with a corresponding one of the

  spring fingers

  40 of the terminal 10. The physical contact between the

  flat pads

  64 and

  spring fingers

  40 is operative for supplying a good electrical contact adequate for transferring electrical current with minimal resistive loss. Upon engagement of the

  battery pack

  18 within the battery-receiving

  cavity

  24 in a latched condition, the terminal 10 operates via electrical power supplied from the battery cell of the

  battery pack

  18.

• The sealed

  case

  48 of the

  battery pack

  18 is sealed against the entry of moisture or other liquids. To that end, the sealed

  case

  48 may be molded as multiple sections and subsequently joined by any suitable technique, such as ultrasonic welding, that provides a water-tight enclosure. The

  electrical contacts

  62 provide the only external connections with

  battery cell

  47 and have a liquid-tight seal with the corresponding openings in the contact-containing

  portion

  54. For example, the

  electrical contacts

  62 may be press-fit into the corresponding openings in the contact-containing

  portion

  54 or the sealed

  case

  48 may be molded about the

  electrical contacts

  62.

• In addition, the sealed

  case

  48 of the

  battery pack

  18 is free or any projecting elements, such as tabs or the like, that would otherwise cooperate with a latching mechanism. The absence of such projecting elements makes the

  battery pack

  18 less prone to damage from, for example, being dropped onto a hard surface that would prevent positive engagement with

  terminal

  10. As a result, the

  battery pack

  18 is sturdy and robust because the battery-receiving

  cavity

  24 that provides the positive engagement with the

  battery latch mechanism

  20 is not susceptible to damage that would result in an inability to mechanically couple the

  battery pack

  18 with the terminal 10.

• With continued reference to

  FIG. 2

  , the

  peripheral edge

  53 of sealed

  case

  48 further includes a

  lip

  66 and a

  latch cavity

  68 with an entrance or opening therein oriented for engagement with the

  battery latch mechanism

  20 when the

  battery pack

  18 is inserted into the battery-receiving

  cavity

  24. The

  lip

  66 and

  latch cavity

  68 extend transversely into and out of the plane of the page of

  FIG. 2

  . The

  latch cavity

  68 has a triangular cross-sectional profile in a transverse direction. The

  lip

  66 includes an outwardly-facing

  planar surface

  70 that defines a lower surface of the

  latch cavity

  68 and an inwardly-facing

  inclined camming surface

  72 of the

  lip

  66 oriented downwardly toward the

  base wall

  30 of the battery-receiving

  cavity

  24 when the

  battery pack

  18 is inserted into the battery-receiving

  cavity

  24. The

  inclined camming surface

  72 is coextensive with the

  planar surface

  70 along a shared

  transverse edge

  74.

• With reference to

  FIGS. 2, 5

  and 5A, the

  battery latch mechanism

  20 is positioned within the battery-receiving

  cavity

  24 and proximate to end

  wall

  27. The

  battery latch mechanism

  20 is actuatable between to provide a latched condition in which the

  battery pack

  18 is secured within the battery-receiving

  cavity

  24 and a latched condition in which the

  battery pack

  18 is readily removable from the battery-receiving

  cavity

  24. The

  battery latch mechanism

  20 includes a latching

  member

  76 movable between an extended position (

  FIGS. 2 and 4

  ) and a retracted position (

  FIG. 3

  ), an actuator or

  release button

  78 in the form of a pushbutton depressible to cause the latching

  member

  76 to move between the extended and retracted positions, and a

  bracket member

  80 pivotally coupling the

  release button

  78 with the

  terminal housing

  22 of the terminal 10. The

  bracket member

  80 of the

  battery latch mechanism

  20 is secured to the

  terminal housing

  22 with

  conventional fasteners

  81 or the like.

• The latching

  member

  76, the

  release button

  78, and the

  bracket member

  80 may be molded from a polymer resin. In particular, the

  release button

  78 and the

  bracket member

  80 may be molded from any polymer resin having good low temperature characteristics useful when the terminal 10 is exposed to a low temperature ambient environment. For example, the

  release button

  78 and the

  bracket member

  80 may be formed from a mixture of polycarbonate with either polybutylene terephthalate (PBT) or polyethylene terephthalate (PET), such as the family of such polymer resins available commercially under the tradename XENOY® from GE Plastics (Seven Hills, Ohio).

• With continued reference to

  FIGS. 2, 5

  and 5A, a biasing

  member

  82, such as a compression spring, urges or biases the latching

  member

  76 to the extended position when the

  release button

  78 is not depressed. One end of the biasing

  member

  82 fits over a

  guide post

  83 formed on the

  release button

  78. An opposite end of the biasing

  member

  82 abuts

  end wall

  27 of the

  terminal housing

  22. The biasing

  member

  82 is constrained against lateral movement by a pair of transversely-spaced

  guides

  84, 85 projecting outwardly from the

  base surface

  32 and a pair of transversely-spaced

  prongs

  86, 87 projecting inwardly from the

  bracket member

  80. While the biasing

  member

  82 is illustrated as a compression spring, the invention contemplates that other types of springs, plastic cantilevers, or elastic members may also be used for biasing the latching

  member

  76 toward the extended position.

• The

  release button

  78 is pivotal relative to the

  bracket member

  80 about a transverse axis of rotation defined by a transversely-spaced pair of pivot pins 88, of which one

  pivot pin

  88 is shown, that also secure the

  release button

  78 mechanically with the

  bracket member

  80. A pair of transversely-spaced

  flanges

  89, 90 are provided on the

  release button

  78 and project inwardly toward the

  base surface

  32. The transverse space between the

  flanges

  89, 90 is dimensioned to receive therebetween the

  prongs

  86, 87 of the

  bracket member

  80. The

  flanges

  89, 90 extend into a corresponding pair of transversely-oriented

  grooves

  91, 92 provided on the latching

  member

  76. When the

  release button

  78 is depressed, the angular rotation of the

  release button

  78 about the pivot pins 88 is converted by the engagement between the

  flanges

  89, 90 and

  grooves

  91, 92 into a longitudinal displacement of the latching

  member

  76 that moves the latching

  member

  76 toward the

  end wall

  27 from the extended position to the retracted position. Similarly, when the latching

  member

  76 is in the retracted position and the

  release button

  78 is released, the angular rotation of the

  release button

  78 in the opposite angular direction about the pivot pins 88 is converted into a longitudinal displacement of the latching

  member

  78 away from the

  end wall

  27 due to the engagement between the

  flanges

  89, 90 and

  grooves

  91, 92 and the restoring force supplied by the biasing

  member

  82 so that the latching

  member

  76 moves from the retracted position (

  FIG. 3

  ) to the extended position (

  FIGS. 2 and 4

  ).

• An inwardly-projecting

  flange

  93 provided on the

  release button

  78 abuts an upwardly-facing surface of a transversely-oriented, outwardly-facing

  slot

  94 provided in the latching

  member

  76.

  Flange

  93 has a longitudinally spaced relationship with

  flanges

  89, 90. The latching

  member

  76 is slidingly captured between the tip of the

  flange

  93 and the

  base surface

  32 so that the latching

  member

  76 cannot cantilever outwardly relative to the engagement between the

  flanges

  89, 90 and

  grooves

  91, 92 during movement between the extended and retracted positions.

• With continued reference to

  FIGS. 2, 5

  and 5A, a battery-engaging

  element

  96 projects from the latching

  member

  76 toward the interior of the battery-receiving

  cavity

  24 of the terminal 10. The battery-engaging

  element

  96 has a

  planar surface

  98 facing the

  base surface

  32 of the battery-receiving

  cavity

  24 and an

  inclined camming surface

  100 positioned opposite to the

  planar surface

  98. The battery-engaging

  element

  96 is captured within the

  latch cavity

  68 when the

  battery pack

  18 is present in the battery-receiving

  cavity

  24 and the latching

  member

  76 is in the extended position (

  FIG. 2

  ). In particular, the

  planar surface

  98 of the battery-engaging

  element

  96 contacts the

  planar surface

  70 of the

  lip

  66 for securing the

  battery pack

  18 within the battery-receiving

  cavity

  24 in the latched condition. The engagement between the

  planar surfaces

  70, 98 prevents outward movement of the

  battery pack

  18 relative to the

  terminal housing

  22. When the latching

  member

  76 is in the retracted position (

  FIG. 3

  ), the battery-engaging

  element

  96 is not captured within the

  latch cavity

  68 and the

  battery pack

  18 is movable within the battery-receiving

  cavity

  24 due to the extension of the

  spring fingers

  40 and the associated bias force applied again the

  flat pads

  64. The

  peripheral edge

  53 of the battery pack also pushed slightly upward out of the battery-receiving

  cavity

  24. It is contemplated by the invention that additional springs, plastic cantilevers, or other elastic members may be used to apply motive force to the

  battery pack

  18 in addition to, or instead of, the

  spring fingers

  40.

• The inclination angle of the

  inclined camming surface

  100 of the battery-engaging

  element

  96 is complementary to the inclination angle of the

  inclined camming surface

  72 of the

  lip

  66. The

  battery pack

  18 is placed in the unlatched condition when the latching

  member

  76 is fully in the extended position and the inclined camming surfaces 72, 100 are abutting. In the unlatched condition, the

  battery pack

  18 is lifted by the engagement between the inclined camming surfaces 72, 100 and may be manually removed from the battery-receiving

  cavity

  24. Manual removal is facilitated by the outward projection of an

  upper corner

  102 of

  peripheral edge

  53 of the

  battery pack

  18 above the

  outer surface

  23 of the

  terminal housing

  22. The

  upper corner

  102 is readily grasped by a worker for removal of the

  battery pack

  18.

• With continued reference to

  FIGS. 2, 5

  and 5A, an outwardly-facing

  surface

  104 of the

  release button

  78 has a convex curvature that generally conforms with the convex curvatures of the

  outer surface

  23 of the

  terminal housing

  22 and the outwardly-facing

  surface

  58 of the sealed

  case

  48 of the

  battery pack

  18. The portion of the

  terminal housing

  22 surrounding the

  release button

  78 operates as a guard to prevent inadvertent latching and unlatching from incidental contact with outwardly-facing

  surface

  104. As a result, a worker is generally required to make a specific and deliberate effort to apply an inward force to pivot the

  release button

  78 for unlatching the

  battery pack

  18. This, therefore, reduces the likelihood of damage to the

  battery pack

  18 from inadvertently falling out of the

  terminal housing

  22.

• Provided on the

  release button

  78 is a set of finger grips 106 that reduce slippage with the worker's finger when the

  release button

  78 is pressed to actuate the

  battery latch mechanism

  20. The finger grips 106 project a short distance outwardly above the

  surface

  104 of the

  release button

  78 that is insufficient to allow inadvertent actuation of the

  release button

  78 and insufficient to significantly interrupt the smooth, curved contour presented collectively by

  surfaces

  23, 58, 104.

• In use and with reference to

  FIGS. 2-4

  , the

  battery pack

  18 is initially in the latched condition shown in

  FIG. 2

  with the battery-engaging

  element

  96 of the latching

  member

  76 engaged within the

  latch cavity

  68 of the sealed

  case

  48 of

  battery pack

  18. To remove the

  battery pack

  18 from the battery-receiving

  cavity

  24, an inward force is applied to push or depress the

  release button

  78 in a general direction indicated by arrow 108 in

  FIG. 3

  . The inward force causes the

  release button

  78 to pivot about pivot pins 88 relative to the

  bracket member

  80. The pivoting of the

  release button

  78 displaces the latching

  member

  76 toward

  wall

  27 in a general direction indicated by

  arrow

  110 in

  FIG. 3

  due to the engagement between

  flanges

  89, 90 and

  grooves

  91, 92 from the extended position toward the retracted position. The biasing

  member

  82 is compressed for applying a restoring force after the inward force applied to release

  button

  78 is removed. When the latching

  member

  76 is fully in the retracted position, the battery-engaging

  element

  96 is released from the

  latch cavity

  68 and the

  battery pack

  18 is released or freed for movement within the battery-receiving

  cavity

  24.

• The

  spring fingers

  40 of the

  electrical contacts

  34, which are compressed when the

  battery pack

  18 is latched, collectively exert a lateral propulsive or motive force against the

  battery pack

  18 that is directed away from

  end wall

  28 as the spring compression is released. The lateral motive force displaces or moves the

  battery pack

  18 toward the

  battery latch mechanism

  20 in a direction generally indicated by

  arrow

  112 in

  FIG. 3

  . As the

  battery pack

  18 moves away from

  end wall

  28, a

  camming surface

  105 on the

  peripheral edge

  53 of sealed

  case

  48 engages a

  mating camming surface

  103 on the

  terminal housing

  22, causing the end of the

  battery pack

  18 to elevate in a direction indicated by

  arrow

  114 in

  FIG. 3

  so that the

  corner

  102 and elevated end of the

  battery pack

  18 project above the

  outer surface

  23 of the

  terminal housing

  22 of the

  terminal housing

  22 in the unlatched condition. The

  opposed end

  50 of sealed

  case

  48 remains captured between the

  lip portion

  44 and

  base wall

  30 of the

  terminal housing

  22.

• The cooperating camming surfaces 103, 105 at the interface between

  battery pack

  18 and

  terminal housing

  22 work with the propulsive force supplied by the

  electrical contacts

  34 to lift the end of the

  battery pack

  18 partially out of the battery-receiving

  cavity

  24 where

  battery pack

  18 can be grasped using the same finger that actuated the

  release button

  78. The

  depressed release button

  78 provides a space for the finger to contact the

  corner

  102 and elevated end of the

  battery pack

  18. This makes possible a rapid one-hand removal of the

  battery pack

  18.

• When the inward force applied to the

  release button

  78 is removed as shown in

  FIG. 4

  , the restoring force applied by the biasing

  member

  82 pivots the

  release button

  78 to its initial position and the latching

  member

  76 moves from the retracted position back toward the extended position. As a result, the

  inclined camming surface

  100 of the latching

  member

  76 slidingly engages the

  inclined camming surface

  72 of the

  battery pack

  18 and displaces or lifts the

  peripheral edge

  53 of the

  battery pack

  18 further outwardly relative to the battery-receiving

  cavity

  24 in the general direction of

  arrow

  114. As a result, the

  corner

  102 of the

  peripheral edge

  53 projects an additional distance above the contour of the

  outer surface

  23 of the

  terminal housing

  22 sufficient for removing the

  battery pack

  18 from the battery-receiving

  cavity

  24. The continued engagement between the inclined camming surfaces 72, 100, after the sliding relative movement therebetween ceases, holds the

  battery pack

  18 in the unlatched condition in which the

  battery pack

  18 can be easily disengaged from the battery-receiving

  cavity

  24 and removed from the terminal 10 by single-handed manual manipulation. The hand of the worker is positioned to cradle the

  battery pack

  18 during removal from terminal 10 so that the risk of dropping is reduced. The removal of the

  battery pack

  18 may be accomplished with one hand and while the terminal 10 remains secured to belt 12.

• The

  battery pack

  18 is replaced by inserting the

  end

  50 of the

  battery pack

  18 into the battery-receiving

  cavity

  24 so that the

  flat pads

  64 contact the

  spring fingers

  40 and the

  shoulder

  56 of the

  battery pack

  18 is captured between the

  lip portion

  44 and

  base surface

  32 of the

  terminal housing

  22. An inward force applied to the sealed

  case

  48 adjacent to end 52 toward the

  base surface

  32 causes the latching

  member

  76 to move from the extended position to the retracted position against the biasing force of the biasing

  member

  82 by sliding contact between the inclined camming surfaces 72, 100. As the

  battery pack

  18 is further pressed into the battery-receiving

  cavity

  24,

  inclined camming surface

  100 slides over

  transverse edge

  74 and the latching

  member

  76 is urged by the biasing

  member

  82 away from the

  end wall

  27 so that the battery-engaging

  element

  96 protrudes into the latching

  cavity

  68. Contact between

  planar surfaces

  70, 98 provides a positive stop to place the

  battery pack

  18 at the proper insertion depth in the battery-receiving

  cavity

  24. When the

  battery pack

  18 is thus completely inserted into the battery-receiving

  cavity

  24, outward movement of the

  battery pack

  18 is prevented and each of the

  flat pads

  64 of the

  battery pack

  18 is electrically coupled with a corresponding one of the

  spring fingers

  40 of the terminal 10. The installation of the

  battery pack

  18 may be accomplished with one hand and while the terminal 10 remains secured to belt 12. The

  battery pack

  18 fits snugly in the battery-receiving

  cavity

  24 so that movement of the

  battery pack

  18 is restricted and the engagement between the

  spring fingers

  40 and

  flat pads

  64 is maintained as the terminal 10 is transported by the worker for use in the warehouse environment.

• According to the principles of the invention, the battery pack can be quickly, easily, and effectively attached to the terminal and removed from the terminal. As a result, battery management procedures are simplified for active workers and delays associated with power issues are reduced. The principles of the invention improve worker efficiency and effectiveness. In addition, the principles of the invention act to ruggedize the terminal and battery pack so that operational lifetimes are lengthened.

• The battery latch mechanism and battery pack of the invention cooperate to provide a desired combination of substantial resistance to inadvertent detachment from the terminal and efficient battery replacement. Specifically, the battery pack is not overly susceptible to falling off or out of the terminal during use because of the secure attachment to the terminal. Moreover, the small surface area of the outwardly-facing surface of the release button that makes the release button resistant to actuation by inadvertent applied forces. In addition, the conforming surface contours of the terminal housing, battery pack and release button reduce the likelihood that contact with an object will dislodge the battery pack from the battery-receiving cavity. As a result, delays in worker activities resulting from unintended separation of the battery pack from the terminal are reduced. In addition, the useful lifetime of the battery pack is extended because the battery pack is less likely to be inadvertently separated from the terminal and damaged by impact with, for example, a concrete floor.

• The battery pack is removable from the battery-receiving cavity with a minimal applied force yet is retained with a sufficient retaining force, when the latch mechanism is initially actuated, so that the battery pack does not readily disengage from the terminal during an operation exchanging a depleted battery pack for a charged battery pack. The magnitude of the applied force required to separate the battery pack from the terminal, when the battery latch mechanism is disengaged from the battery pack, permits a worker to replace a depleted battery pack in a one-handed operation while the terminal remains attached to the worker. As a result, the tediousness entailed in the removal and replacement of the battery pack is significantly reduced by the improved ergonomics and the impact to the worker's work schedule is lessened.

• According the principles of the invention, the electronics within the terminal are isolated from exposure to harsh ambient operating environments in which the terminal is being used. In addition, the battery pack provides a sealed environment that isolates the battery cell from the infiltration of moisture and other contaminants from the operating environment or condensation arising from changes in the humidity level and temperature of the operating environment. As a result, the terminal and battery pack are significantly less susceptible to electrical shorts and malfunctions.

• While the present invention has been illustrated by the description of the various embodiments thereof, and while the embodiments have been described in considerable detail, it is not intended to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. The invention in its broader aspects is therefore not limited to the specific details, representative apparatus and methods and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the scope or spirit of Applicants' general inventive concept.