Fuse holder with circumferential fuse encapsulation

Abstract

A fuse holder, comprising a first contact body having a first receptacle with a center axis, the first receptacle being formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the first contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void, and wherein the first contact body includes a first circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the first contact body to a first conductor of the circuit board, and a second contact body having a second receptacle with a center axis, the second receptacle being formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the second contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void, and wherein the second contact body includes a second circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the second contact body to a second conductor of the circuit board, wherein the fingers of the first receptacle define a cylindrical cavity that is circumferentially complete except for the axially extending voids between adjacent ones of the fingers of the first contact body, and wherein the fingers of the second receptacle define a cylindrical cavity that is circumferentially complete except for the axially extending voids between adjacent ones of the fingers of the second contact body.

Description

FUSE HOLDER WITH CIRCUMFERENTIAL FUSE ENCAPSULATIONTechnical Field

[0001] The present disclosure relates generally to a fuse holder and more particularly for a fuse holder that is coupled to a fuse and to a circuit board or printed circuit board.Background

[0002] A fuse holder is a device used to hold and protect a fuse in an electrical circuit. It provides a secure connection for the fuse and ensures that it is held firmly in place. The fuse holder also serves as a safety feature by enclosing the fuse, preventing accidental contact with live parts and reducing the risk of electrical shock or fire. Fuse holders can take up valuable physical space in electrical panels or enclosures. This can be a limitation in applications where space is limited or compact designs are required. Additionally, larger fuse holders may require additional clearance for safe operation, which can further impact the overall space requirements. In addition, due to this space limitation, the assembly and disassembly of the fuses can be an issue and the known solutions to facilitate the fuse disassembly could lead to an unintentional removal of the fuse from the holder.Disclosure of the Invention

[0003] According to an aspect of the invention, a fuse holder terminal for a circuit board is provided. The fuse holder terminal comprises: a contact body having a receptacle with a center axis, the receptacle being formed by multiplefingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void, and wherein the contact body includes a circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the contact body to a conductor of the circuit board; and wherein the fingers of the receptacle define a cylindrical cavity that is circumferentially complete except for the axially extending voids between adjacent ones of the fingers of the contact body.

[0004] According to another aspect of the invention, a fuse holder terminal for a circuit board is provided. The fuse holder terminal comprises: a contact body having a receptacle with a center axis, the receptacle being defined in part by a flexible conductor having an inner surface spaced from the center axis, and wherein the contact body includes a circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the contact body to a conductor of the circuit board; and wherein the conductor has an inner surface that circumferentially spans between 300 degrees and 360 degrees.

[0005] According to still another aspect of the invention, a fuse holder is provided. The fuse holder comprises: a first contact body having a first receptacle with a center axis, the first receptacle being formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the first contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void, and wherein the first contact bodyincludes a first circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the first contact body to a first conductor of the circuit board; and a second contact body having a second receptacle with a center axis, the second receptacle being formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the second contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void, and wherein the second contact body includes a second circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the second contact body to a second conductor of the circuit board, wherein the fingers of the first receptacle define a cylindrical cavity that is circumferentially complete except for the axially extending voids between adjacent ones of the fingers of the first contact body, and wherein the fingers of the second receptacle define a cylindrical cavity that is circumferentially complete except for the axially extending voids between adjacent ones of the fingers of the second contact body.

[0006] According to a further aspect of the invention, a circuit board assembly is provided. The circuit board assembly comprises a circuit board having conductive portions defining part of a circuit, and a first opening and a second opening; a first contact body having a projection receivable in the first opening and engagable with one of the conductive portions of the circuit board, and the first contact body has a fuse receptacle formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the first contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void; anda second contact body having a projection receivable in the second opening and engagable with one of the conductive portions of the circuit board, and the second contact body has a fuse receptacle formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the second contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void.

[0007] According to another aspect of the invention, a fuse holder is provided. The fuse holder comprises a first contact body having a first receptacle with a center axis, the first receptacle being defined in part by a first flexible conductor having an inner surface spaced from the center axis, and wherein the first contact body includes a first circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the first contact body to a first conductor of the circuit board; and a second contact body having a second receptacle with a center axis, the second receptacle being defined in part by a second flexible conductor having an inner surface spaced from the center axis, and wherein the second contact body includes a second circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the second contact body to a second conductor of the circuit board, wherein the first conductor and second conductor have an inner surface that circumferentially spans between 300 degrees and 360 degrees.

[0008] Other aspects and features are defined in the appended claims.

[0009] Examples of the disclosure may make it possible to obtain a fuse holder terminal and a fuse holder that facilitates the assembly and disassembly of the fuse. Specifically, the present fuse holder terminal and the present fuse holder configuration ensures a easy replacement andprevents unintended removal of the fuse. Other possible advantages will be apparent in the following detailed description.Brief Description of the Drawings

[0010] The following detailed description of preferred implementations and best mode will be set forth with regard to the accompanying drawings, in which:

[0011] FIG. 1 is a perspective view of part of a circuit board including a fuse holder with a fuse installed therein;

[0012] FIG. 2 is a perspective view like FIG. 1 and showing the fuse holder removed from the circuit board;

[0013] FIG. 3 is a perspective view like FIG. 2 and showing the fuse removed from the fuse holder;

[0014] FIGS. 4-6 show a fuse holder in positions like those described above with reference to FIGS.1-3;

[0015] FIGS. 7-9 show a fuse holder in positions like those described above with respect to FIGS. 1- 3;

[0016] FIG. 10 shows a portion of a circuit board and a first part of a contact body of a fuse holder adapted to be connected to the circuit board;

[0017] FIG. 11 is an end view of a receptacle of a fuse holder;

[0018] FIG. 12 is a side view of a finger of a receptacle;

[0019] FIGS. 13-15 show a fuse holder in positions like those described above with respect to FIGS. 1-3; and

[0020] FIG. 16 is a perspective view of a fuse holder showing an internal conductor.Detailed Description

[0021] Referring in more detail to the drawings, FIGS. 1-3 illustrate a fuse 10 coupled to the circuit board 12 by a fuse holder 14. In this way, a fuse 10 is coupled to a circuit 16 incorporated / provided at least in part on the circuit board 12. It is noted that the fuse holder 14 is formed by two fuse holder terminals opposite each other configured to hold each an end of the fuse 10. The fuse holder 14 includes therefore a first contact body 18 (being a part of a first fuse holder terminal) coupled to the circuit board 12 and adapted to electrically contact and retain a first end 20 of a fuse 10, and a second contact body 22 (being a part of a second fuse holder terminal) also coupled to the circuit board 12 and adapted to electrically contact and retain an opposite, second end 24 of the fuse 10. The fuse holder 14 is constructed to provide robust contact and retention of the fuse 10 while permitting easy replacement of the fuse 10.

[0022] In at least some implementations, the fuse 10 may be a so-called cartridge fuse 10, as best shown in FIG. 3, including a cylindrical and tubular body 26, made of glass or other material, and metal end caps 28 at the opposite first and second ends 20, 24 of the fuse 10 that are electrically connected to an internal fuse member 30 (shown in dashed line) which may be a wire. To electrically connect the fuse 10 within a circuit 16, the fuse holder 14 is electrically connected in the circuit 16 and to the fuse 10 by engagement with the end caps 28. In this way, current in the circuit 16 passes through the contact bodies18, 22 of the fuse holder 14 and the fuse 10.

[0023] The circuit board 12 as shown in the drawings is simplified and it is understood that the circuit board 12 may include many electrical circuit components and conductors, such as wires or metallic traces 40, connected to the circuit components to define all or part of one or more circuits. While one fuse 10 is shown in the drawings, multiple fuses may be provided on a single circuit board 12, as desired.

[0024] Several implementations of fuse holders are shown in the drawings. In FIGS. 1-3, the fuse holder 14 includes spaced apart first and second contact bodies 18, 22 that may be constructed identically and so only one of the contact bodies 18 will be described in detail, to facilitate the description and understanding of the fuse holder 14.

[0025] The first contact body 18 includes a fuse receptacle 32 at a first end 34, and a circuit board coupler 36 at its other end. The circuit board coupler 36 is adapted to be mechanically and electrically coupled to the circuit board 12 to mount the first contact body 18 on or to the circuit board 12 and to electrically couple the first contact body 18 to a circuit 16 carried by the circuit board 12.

[0026] In the example shown, and with reference to FIG. 3, the circuit board coupler includes a projection such as a post or pin 36 that is plugged into an opening 38 in the circuit board 12 and engaged with a trace 40 or wire to connect the pin 36 in a circuit 16 on the circuit board 12. The opening 38 may be defined by or lined with a conductive member, such as a metal bushing 42 or the like, and either the pin 36 or bushing 42 or both may have a spring portion that permits some flexing and resilience to provide a better fit and interface between them. The bushing 42 may be connected to a trace 40 or wire of the circuit 16 in known manner. As shown in FIG. 3, the pin 36 may have a central axis 44 and be cantilevered to and protrude from a base 46 that defines at its bottom or lower end a radially outwardly extending flange 48 that circumferentially surrounds the pin 36. To facilitate mounting the first contact body 18 to the circuit board 12, the central axis 44 of the pin 36 may be coaxial with a central axis 50 of the opening 38, and thepin 36 may be received in the opening 38 until the flange 48 engages a surface 52 of the circuit board 12. One or both of the pin 36 and the flange 48 may be electrically coupled to the circuit board 12, such as by physical / mechanical contact with a conductor carried by the circuit board 12.

[0027] In the example shown in FIGS. 1-3, the pin 36 is part of a metallic body 54 that is formed separately from and connected to the base 46 in any desired manner, and is shown as extending through a hole in the base 46 and its flange 48. In the example fuse holder 14’ shown in FIGS. 4-6, the pin 36’ is integrally formed in the same piece of material as the base 46’ such that these components are features of the same body. Accordingly, the first contact body 18 can be formed in one-piece or more than one piece. To facilitate understanding of the example shown in FIGS. 4-6, the same reference numerals are used to denote like parts and features with respect to the assembly shown in FIGS. 1-3.

[0028] The base 46 of the contact body 18 may extend to the fuse receptacle 32, and the fuse receptacle 32 defines a cavity 56 in which the first end 20 of the fuse 10 is received. The base 46 and first contact body 18 in general define a continuous electrical conductor from the fuse receptacle 32 to the pin 36. Thus, when a fuse 10 is received in the receptacle 32 and the pin 36 / base 46 are coupled to the circuit board 12, the fuse 10 is electrically connected within the circuit 16.

[0029] In at least some implementations, the fuse receptacle 32 is defined by multiple fingers 58 that are cantilevered to and extend from the base 46 at a first end 60 to a second end 62 that is not directly attached to the base or another structure and may be a called a free end. Adjacent fingers 58 are separated from each other by a void 64, and the fingers 58 may be flexible and resilient to permit flexing of the fingers 58 relative to the base 46 which changes an effective size or diameter of an inlet end 66 of the fuse receptacle 32, where the inlet end 66 is defined by the second ends 62 of the fingers 58. The fingers 58 may be evenly radially spaced from a central axis 68 of the receptacle 32, and an effective size (e.g. bounded area) of theinlet end 66 is defined by radially inner surfaces 70 of the fingers 58 at their second ends 62, which may be chamfered or beveled, as shown in FIG. 12, to facilitate alignment and insertion of a fuse 10 into the fuse receptacle 32. In a first state, in which a fuse 10 is not received in the receptacle 32, the effective size of the inlet end 66 may be smaller than in a second state in which a fuse 10 is received in the receptacle 32. That is, one or more and up to all of the fingers 58 may flex radially outwardly when a fuse 10 is inserted into the receptacle 32. In this way, and due to the resilient nature of the fingers 58 which causes them to tend to return radially inwardly to their position in the first state of the contact body, physical contact between the fingers 58 and the fuse 10 can be assured to provide a reliable and robust conductive connection. The size of the receptacle 32 in the first state can be designed relative to a size of fuse 10 to be inserted into the receptacle, to ensure that the fingers 58 flex within their elastic range of deformation and are not plastically deformed. This improves the useful life of the contact body over repeated insertions and removal of fuses.

[0030] FIGS. 1-3 show positions of the fuse holder 14 during a process of replacing the fuse 10. In FIG. 1, the fuse holder 14 is coupled to the circuit board 12 and to the fuse 10. In this assembled position, two fuse holder terminals are coupled to the circuit board 12 and to each end of the fuse 10, i.e. both the first and second contact bodies 18, 22 are received in respective openings 38 of the circuit board 12 and are electrically coupled to a conductor on the circuit board 12, shown as metal traces 40. Also, the first end 20 of the fuse 10 is received within the fuse receptacle 32 of the first contact body 18 and the second end 22 of the fuse 10 is received within the fuse receptacle 32 of the second contact body 22, with the fingers 58 defining each fuse receptacle 32 engaged with the fuse 10, as described above. In this position, the fuse receptacles 32 of the contact bodies 18, 22 face in opposite directions, and are coaxially aligned with each other and with the fuse 10.

[0031] FIGS. 2 and 3 show different positions of the fuse holder 14 to permit replacement of a fuse 10. From the position of FIG. 1 to the position of FIG. 2, the contact bodies 18, 22 have been removed fromthe circuit board 12, by removing the pins 36 from their respective openings 38 with a force applied along the axis 44 / 50. Next, as shown in FIG. 3, the contact bodies 18, 22 can be removed from the fuse 10, with a force applied along the axis 68 of the receptacles 32. In this way position, a new fuse 10 can be inserted into the receptacles 32 and the contact bodies 18, 22 can be recoupled to the circuit board 12, a reversal of the positions from FIG. 3 to FIG. 2 to FIG. 1. Similar positions are shown in FIGS. 4-6 with regard to the contact bodies 18, 22 formed from a single piece of material, and a similar assembly / disassembly process may be used in this implementation.

[0032] In the implementation shown in FIGS. 7-9, a fuse holder 71 includes first and second contact bodies 72, 74 that each are formed in more than one piece, and which couple a fuse 10 to a circuit board 12 in a similar manner as described above with reference to FIGS. 1-6. The first and second contact bodies 72, 74 are part of a first and a second fuse holder terminal, respectively. The first and second contact bodies 72, 74 may be constructed identically and so only one of the contact bodies will be described in detail, to facilitate the description and understanding of the fuse holder 71. Further, to facilitate understanding of the fuse holder 71 , the same reference numerals are used to denote like parts and features with respect to the assembly shown in FIGS. 1-3.

[0033] In this implementation, the contact body 72 includes a first part 76 that is connected to the circuit board 12 and a second part 78 that is removably or releasably coupled to the first part 76 to permit selective coupling and removal of the second part 78 from the first part 76 as set forth in more detail below. In at least some implementations, the first part 76 may be fixed to the circuit board 12 by which it is meant that the first part 76 need not be removed from the circuit board 12 to replace a fuse 10 in the fuse holder 14. The first part 76 could be removably connected to the circuit board 12, such as by a friction fit or with a clip or other mechanical connector, of the first part 76 may be soldered or otherwise joined to the circuitboard 12. In this way, damage to the circuit board 12 by the repeated removal and insertion of the pin 36 into / through the opening 38 in the circuit board 12 can be avoided. This may be desirable as repair or replacement of the circuit board 12 may be more difficult or costly than repair or replacement of the second part 78 of the contact bodies 72, 74.

[0034] In the example shown in FIGS. 7-9, the first part 76 includes a base 80 that is connected to the circuit board 12 and which may include a projection / pin received in an opening 38 in the circuit board 12, and the first part 76 includes a post 82 extending away from the circuit board 12, and which may have an axis 84 that may be perpendicular to the upper surface 52 of the circuit board 12, in at least some implementations. The first part 76 may be formed in a single piece of material or in multiple pieces connected together, as desired. Further, the post 82 may be solid and cylindrical, or of a different shape and / or hollow, as desired. With a hollow post, it is possible for the second part 78 to be plugged into an interior of the post rather than being plugged onto the exterior of the post as shown.

[0035] As in the implementations of FIGS. 1-6, the second part 78 may include a fuse receptacle 88, which may be constructed and arranged in the same manner as described above with respect to fuse receptacles 32 and below (e.g. with finger 58 and voids 64). To releasably connect the first part 76 and the second part 78, the second part 78 includes a second receptacle 90 adapted to be plugged or pressed onto the post. The second receptacle 90 can be constructed and arranged in the same manner as the fuse receptacle 88, or in any desired manner to provide a mechanical and electrical connection between the first part 76 and the second part 78, e.g., in a plug and socket type connection. That is, the second receptacles 88 may have cantilevered fingers 87 separated by voids 89 that are arranged as set forth herein regarding fingers 58 and voids 64, and receptacles 32 in general.

[0036] In FIG. 7, the fuse holder 14 is shown fully assembled to the circuit board 12 with the first part76 of each contact body 72, 74 connected to the circuit board 12, the second part 78 of each contact body 72, 74 connected to its respective first part 76, and with a fuse 10 received in the fuse receptacles 88 of the contact bodies. In FIG. 8, the second parts 78 of the contact bodies 72, 74 have been removed from the first parts 76, by applying a force parallel to the center axes 84 of the posts 82 and second receptacles 90 and slidably disconnecting the parts 76, 78. Once free of the posts 82, the second parts 78 of the contact bodies 72 ,74 may be pulled off the fuse 10, as shown in FIG. 9 to permit replacement of the fuse 10. After replacement, the first parts 76 can be coupled to the new fuse 10, as shown in FIG. 8, and then the first parts 76 can be coupled again to the second parts 78 of the contact bodies 72, 74, as shown in FIG. 7.

[0037] In this way, the first parts 76 of the contact bodies 72, 74 can remain connected to the circuit board 12 throughout use of the fuse holder 14 and the second parts 78 can be removed from the first parts 76 to permit separation from a fuse 10. Further, the post 82 can be made to be durable and so fixing the first part 76 to the circuit board 12 can be done without fear of having to replace the post 82 in the future. On the other hand, the receptacles 88, 90 may tend to wear out after multiple insertions onto the post 82, or insertions of a fuse 10 therein, and with the second parts 78 of the contact bodies 72, 74 being separate components, the second parts 78 of the contact bodies can be replaced if needed, without disturbing the circuit board 12. While the above may be true, a contact body may also include, as shown in FIG. 10, a first part 76’ of a contact body 72’ that is coupled to the circuit board 12 at one end (e.g. via a pin 36) and includes a receptacle 94 arranged to receive a mating portion of the second part 78 of the contact body 72’, where the mating portion may be a post or plug insertable into the receptacle. The first part 76, 76’ may be soldered to or otherwise coupled to the circuit board 12 so that it is not intended to be removed from the circuit board 12 to change the fuse 10. And the first part 76, 76’ in this example may be formed in a single piece of material or in multiple pieces connected together, as desired.

[0038] In at least some implementations, the receptacles 32, 88, 90, 94 are defined at least in part by one or more flexible conductor members that are arranged to directly contact a fuse installed in the fuse holders. In the examples shown in FIGS. 1-9, the receptacles are defined by three or more fingers 58. For example, in the receptacle 32 shown in FIG. 11, six fingers 58 are provided and the fingers 58 collectively define a circular inner surface or inner diameter of the receptacle, which is circumferentially discontinuous due to the voids 64 between adjacent fingers 58. Of course, other numbers of fingers 58 may be provided. The fingers 58 may be sections of a cylindrical tubular portion of the contact body that are separated from each other by cutting or otherwise forming or providing slit- shaped voids 64 in the body. The slits extend axially along the length of the fingers 58, radially between adjacent fingers 58 and through the inlet end 66 of the receptacle 32 so that the fingers 58 are separate from each other along their axial lengths and at their free ends, and with each finger 58 being directly connected to the contact body at its first end 60.

[0039] In at least some implementations, such as that shown in FIG. 11, the fingers 58 have inner surfaces 70 that are curved so that the inner surfaces 70 are at a constant radial distance from the axis 68. In at least some implementations, the fingers 58 collectively circumferentially span at least two-hundred eighty degrees around the axis 68, and the voids 64 between adjacent fingers 58 span eighty degrees or less. For example, in at least some implementations, the fingers 58 span three hundred degrees or more, and the voids 64 span sixty degrees or less. And in some implementations, the voids 64 may be tapered so that they are wider nearer the first end 60 of the fingers 58 and narrower at the second end 62 of the fingers 58, and at the second end 62 the fingers 58 may touch each other, at least in the at rest state without a fuse 10 or other component received therein. In such an embodiment, and in the at rest state, the fingers 58 may define a circumferentially continuous contact area at the inlet 66 of the fuse receptacle 32, with some spacing of the second ends 62 of the fingers 58 occurring when the fingers 58 are flexed. In at least some implementations, the fingers 58 overlap the fuse 10 in four locations that are each spaced apart circumferentially by 90 degrees.Further, in at least some implementations, the axial dimension of the fingers 58 may be greater than their circumferential dimension and their radial thickness. So the greatest dimension of the fingers 58 may be provided parallel to the axis of the fuse 10 (or part of the contact body inserted in a receptacle). In at least some environments, the more exposed the ends of a fuse are to the environment the more oxidation might occur, and the embodiments described herein with greater coverage of the ends of the fuse may reduce oxidation and improve the useful life of the fuse.

[0040] In the example shown in FIGS. 13-15, the fuse holder 100 includes spaced apart first and second contact bodies 102, 104 that may be constructed identically and so only one of the contact bodies 102 will be described in detail, to facilitate the description and understanding of the fuse holder 100. The contact body 102 includes a pin 106 that is integrally formed in the same piece of material as a base 108, similarly to the embodiment shown in FIGS. 4-6. The contact body 102 could instead be formed in multiple connectable pieces of material, such as is shown in FIGS. 1-3 and FIGS. 7-9, if desired.

[0041] With continued reference to FIGS. 13-15, the base 108 of the contact body 102 may extend to a fuse receptacle 110, and the fuse receptacle 110 defines a cavity 112 with a central axis 113 in which the first end 20 of the fuse 10 is received with the axis of the fuse being aligned with the central axis 113. The base 108 and first contact body 102 in general define a continuous electrical conductor from the fuse receptacle 110 to the pin 106. Thus, when a fuse 10 is received in the receptacle 110 and the pin 106 / base 108 are coupled to the circuit board 12, the fuse 10 is electrically connected within the circuit 16.

[0042] In at least some implementations, the fuse receptacle 110 is defined by a cavity 112 defined in the contact body 102 and one or more flexible conductors 114. In the example shown, a single, annular flexible and resilient conductor 114 is provided within a groove 116 formed in an inner surface 118 of the cavity 112, spaced from the inlet end 120 of the cavity 112 into which an end of the fuse 10 is inserted. Theflexible conductor 114 may be a spiral or helical coil of a conductive material, like metal wire, and it may be circumferentially continuous (e.g. annular as noted). The coil may be formed of multiple turns of the metal wire with spaces provided between adjacent portions of adjacent turns.

[0043] As shown in FIGS. 15 and 16, the coiled conductor 114 has an outer diameter that is greater than the diameter of the inner surface 118 of the cavity 112, and an inner diameter, with a radial dimension of the conductor 114 defined between its outer and inner diameters. The radial dimension of the conductor 114 is greater than the radial dimension of the groove 116, so that, when the conductor 114 is within the groove 116, an inner surface of the conductor 114 is radially inwardly spaced from the inner surface 118 of the cavity 112 for engagement with an end cap 28 of a fuse 10. To permit installation of the conductor 114 into the groove through the smaller diameter inlet end 120 of the cavity 112, the conductor 114 flexes so that its outer diameter can be reduced for insertion into the cavity 112 and into the groove 116. Once aligned with the groove, the conductor 114 resiliently expands outwardly into the groove 116 to retain the position of the conductor 114 in the groove 116, with a portion of the conductor 114 projecting radially inwardly into the cavity 112. In this way, an effective or smallest diameter of the cavity 112 is defined by an opening 122 of the conductor 114. The coiled conductor 114 may have a substantially uniform inner diameter with inwardmost portions of the turns being at substantially the same distance from the center axis 113, where substantially means within 15% in this context. The inner diameter of the conductor 114 prior to insertion of a fuse therein may be between 5% and 20% smaller than the outer diameter of a fuse to be inserted therein, to ensure suitable engagement of the conductor 114 with the fuse when installed.

[0044] In a first state, in which a fuse 10 is not received in the receptacle 110, the effective size of the cavity 112 may be smaller than in a second state in which a fuse 10 is received in the receptacle 110, and smaller than an outer diameter of a portion of a fuse 10 inserted in the cavity 112. That is, the conductor114 (e.g. the turns thereof) flexes radially outwardly when a fuse 10 is inserted into the receptacle 112 and through the opening 122 defined by the conductor 114. In this way, and due to the resilient nature of the conductor 114 which causes the turns of the conductor 114 to tend to return radially inwardly to their position in the first state of, physical contact between the conductor 114 and the fuse 10 can be assured to provide a reliable and robust conductive connection. The size of the receptacle cavity 112 and inner diameter of the conductor 114 in the first state can be designed relative to a size of fuse 10 to be inserted into the receptacle 110, to ensure that the conductor 114 flexes within its elastic range of deformation and is not plastically deformed. This improves the useful life of the contact body 102 over repeated insertions and removal of fuses 10. In at least some implementations, the conductor 114 may engage the fuse 10 between 300 degrees and 360 degrees circumferentially around the outer surface of the fuse (e.g. the end caps 28).

[0045] While the contact bodies 102, 104 are shown as having a through hole that defines the cavity 112, the cavities 112 could be closed at their ends opposite the inlet end 120. Further, while the conductor 114 is shown in FIGS. 13-16 as being a single piece of material, it could be formed from multiple pieces of material received in the cavity 112, if desired. Still further, the conductor(s) 114 are shown as being held in the groove 116 by being larger than the groove 116 in an at rest state (e.g. not acted upon or compressed by an outside force), the conductor 114 could be retained in the cavity 112 by one or more fasteners, adhesive, weld or the like.

[0046] FIGS. 13-15 show positions of the fuse holder 100 during a process of replacing the fuse 10. In FIG. 13, the fuse holder 100 is coupled to the circuit board 12 and to the fuse 10. In this assembled position, both the first and second contact bodies 102, 104 have their pins 106 received in respective openings 38 of the circuit board 12 and are electrically coupled to a conductor 40 on the circuit board 12. Also, the first end 20 of the fuse 10 is received within the fuse receptacle 110 of the first contact body 102and the second end 22 of the fuse 10 is received within the fuse receptacle 110 of the second contact body104, with the conductors 114 defining an effective diameter of each fuse receptacle 110 engaged with the fuse 10, as described above. In this position, the fuse receptacles 110 of the contact bodies 102, 104 face in opposite directions, and are coaxially aligned with each other and with the fuse 10.

[0047] FIGS. 14 and 15 show different positions of the fuse holder 100 to permit replacement of the fuse 10. From the position of FIG. 13 to the position of FIG. 14, the contact bodies 102, 104 have been removed from the circuit board 12, by removing the pins 106 from their respective openings 38 with a force applied along the axis 107 (FIG. 13) of the pins 106 and openings 38. Next, as shown in FIG. 15, the contact bodies 102, 104 can be removed from the fuse 10, with a force applied along the axis 113 (FIG. 15) of the receptacles 110. In this way position, a new fuse 10 can be inserted into the receptacles 110 and the contact bodies 102, 104 can be recoupled to the circuit board 12, a reversal of the positions from FIG. 15 to FIG. 14 to FIG. 13. In at least some implementations, the axes 68, 113 of the fuse receptacles 32, 88, 110 are parallel to an adjacent surface 52 of the circuit board 12, which may be planar, and the axis 44, 84, 107 of the part of the contact bodies that is directly coupled to the circuit board 12 is perpendicular to the axis 68, 113 of the fuse receptacle 32, 88, 110 and to the surface 52 of the circuit board 12. In some implementations, the contact bodies may include a bend between the pin 36 / post 82 and the fuse receptacles 32, 88, (e.g. they may be generally L-shaped or T-shaped) so that the fuse receptacle are oriented at an angle of ninety degrees relative to the pin 36 or post 82.

[0048] In at least some implementations, the fuse holder 14 includes contact bodies, which are part of fuse holder terminals, with slidably displaceable parts to facilitate assembly and disassembly of the fuse holder 14 to permit installation or replacement of a fuse 10 in the fuse holder 14 and coupled to the circuit board 12. The receptacles of fuse holders may have a nominal, at rest diameter that is equal to or slightly smaller than the nominal, outside diameter of a component to be inserted therein (a fuse 10 or another partof the contact body). In this way, upon insertion of the component into the receptacle, one or more conductors 58, 114 are elastically / resiliently flexed outwardly to accommodate the component within the receptacle and provide a contact force against the exterior of the component to one or both of create a reliable electrical contact and create a retention force to prevent unintended separation of the component from the receptacle.

[0049] With this arrangement, removal of the fuse requires removal of at least part of a contact body from the circuit board, and the fuse cannot simply be displaced from the fuse holder, which limits or prevents unintended removal of the fuse from the fuse holder. That is, the ends 20, 24 of the fuse 10 are surrounded by the conductors 58, 114 of the fuse receptacles 32, 88, 110 and to remove a fuse 10 from the fuse holder requires displacement of the contact bodies along the axis 68, 113 of the receptacles and the fuse 10, which, in the embodiments shown, also requires displacement of the contact bodies along the axis 44, 107 of the pins 32, 106 or the axis 50 of the openings 38 in the circuit board. The fuse holder provides a robust connection of a fuse, permits easy replacement of a fuse and greatly inhibits or prevents unintended removal of a fuse. While the forms of the invention herein disclosed constitute presently preferred embodiments, many others are possible. It is not intended herein to mention all the possible equivalent forms or ramifications of the invention. It is understood that the terms used herein are merely descriptive, rather than limiting, and that various changes may be made without departing from the spirit or scope of the invention.

[0050] All terms used in the claims are intended to be given their broadest reasonable construction and their ordinary meanings as understood by those skilled in the art unless an explicit indication to the contrary is made herein. In particular, use of the singular articles such as "a," "the," "said," etc. should be read to recite one or more of the indicated elements unless a claim recites an explicit limitation to the contrary.

Claims

CLAIMS1. A fuse holder terminal for a circuit board, comprising: a contact body having a receptacle with a center axis, the receptacle being formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void, and wherein the contact body includes a circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the contact body to a conductor of the circuit board; and wherein the fingers of the receptacle define a cylindrical cavity that is circumferentially complete except for the axially extending voids between adjacent ones of the fingers of the contact body.

2. The fuse holder terminal of claim 1 wherein the receptacle is formed from at least 3 fingers that are circumferentially spaced apart.

3. The fuse holder terminal of claim 2 wherein the fingers circumferentially span at least 300 degrees.

4. The fuse holder terminal of claim 1 wherein each of the voids circumferentially spans not more than 10 degrees.

5. A circuit board assembly, comprising: a circuit board having conductive portions defining part of a circuit, and a first opening and a second opening; a first contact body having a projection receivable in the first opening and engagable with one of the conductive portions of the circuit board, and the first contact body has a fuse receptacle formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger beingcantilevered to the first contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void; and a second contact body having a projection receivable in the second opening and engagable with one of the conductive portions of the circuit board, and the second contact body has a fuse receptacle formed by multiple fingers with each finger being radially spaced from the center axis, and with each finger being cantilevered to the second contact body at a first end and extending axially to a free end, and with adjacent fingers being separated from each other by an axially extending void.

6. The assembly of claim 5 wherein the projections are removably received in the circuit board to permit removal of the first contact body and second contact body from the circuit board openings.

7. The assembly of claim 5 wherein the first contact body is formed in two parts with a first part including the projection and a second part including the receptacle, and wherein the two parts are releasably connectable to permit separation of the two parts to disconnect the second part from the circuit board.

8. The assembly of claim 7 wherein one of the first part and the second part includes a projection and the other of the first part and the second part includes a second receptacle by which the first part and second part are releasably connectable.

9. A fuse holder terminal for a circuit board, comprising: a contact body having a receptacle with a center axis, the receptacle being defined in part by a flexible conductor having an inner surface spaced from the center axis, and wherein the contact body includes a circuit board coupler that is adapted to be coupled to a circuit board to electrically couple the contact body to a conductor of the circuit board; and wherein the conductor has an inner surface that circumferentially spans between 300 degrees and360 degrees.

10. The fuse holder terminal of claim 9 wherein the flexible conductor is annular.

11. The fuse holder terminal of claim 10 wherein the flexible conductor is formed of an electrically conductive and resilient material that yieldably resists radial expansion so that the flexible conductor radially contracts after radial expansion that occurs under a force within the elastic limit of the material of the flexible conductor.

12. The fuse holder terminal of claim 9 wherein the flexible conductor is defined by a plurality of fingers circumferentially spaced apart by voids with a void located between adjacent fingers, and with the fingers of the contact body defining the receptacle.

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