Abstract:
A fuse carrier operable as a surge-current protector for cross-connecting two circuits utilizes standard amperage fuses arranged in an offset alignment and secured in a housing cavity against rotational, longitudinal, and transverse movement with the fuse blades maintained in an aligned and separated position and separate by a platform with an upright protruding member, which fuses are provided in a narrow-housing configuration.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a terminal block assembly and more specifically a current-surge protector for making cross-connections for two rows of terminals, which protector has integral fuses. 
     Fuse holders and fuse assemblies have been known for applications in industry, automobiles and in domestic or home environments. An assembly with a fuse receptacle integral with a dual-pronged wall plug or outlet and having a dual fuse arrangement is illustrated in U.S. Pat. No. 3,833,875 to Holoka. This dual-fuse arrangement utilizes cartridge-type fuses inserted in clips and retained within a housing. The housing has a male end coupled to the fuses at one end of the receptacle and a female receptacle end coupled to the opposite fuse end and operable to receive the mating line cord contacts. U.S. Pat. No. 4,384,282 also discloses a fused plug, which has a spare fuse retained within the plug. 
     Earlier cartridge-type fuse and fuse holder assemblies are exemplified by the fuse assembly illustrated in U.S. Pat. No. 1,938,097 to Curlee, which has a cartridge fuse having blade extensions matable with extending fingers to provide an in-line fuse connection or coupling. The fuse is mounted on a pivotal holder, which may be utilized to remove the fuse and open a circuit. Closing of the fuse box or support and reinserting the fuse blades into the extending fingers again closes the circuit. The fuse may be repaired or replaced in the open-circuit position. A similar fuse holder and fuse are illustrated in U.S. Pat. No. 945,017 to Cole. 
     Multiple fuse adapters and contacts on a single circuitboard are illustrated in U.S. Pat. No. 3,744,003 to Dipace. Similarly, a multiple element holder, which is illustrated as a printed circuit assembly, is shown in Foster U.S. Pat. No. 2,898,519, with a row of parallel components aligned on a circuitboard. 
     Fuses are also known as component devices in switch blocks or switching devices, which is shown in Frank U.S. Pat. No. 1,953,343; Frank U.S. Pat. No. 1,861,267; and Kinasi U.S. Pat. No. 3,872,416, where switches and fuse blocks are integrally combined for varying functions. In Frank-&#39;267, an arrangement is provided with the fuses in a single branch unit, which may be coupled in series to provide a single branch from a double branch unit. In the Frank-&#39;343 device, a panel board is shown with several fuse units, each having a receptacle affixed to the board and connected to a bus bar with a removable fused plug matable with this receptacle. A mounting plate, bus bars and panel board for switch blocks, fuse clips, etc., are generally equipped with the elements permanently fastened to the mounting plate. However, the Frank-&#39;343 apparatus provided a switch block utilizing female members detachably mounted on adjacent bus bars and a male member connectable to the female members, which allowed a sectional panel board to be built on and interchanged with other panel boards. 
     Kinasi U.S. Pat. No. 3,872,426 disclosed a fuse holder arrangement, which is particularly used in an automobile. The fuse holder utilizes a male-female connection where the female member is a fuse box or holder. The male member is insertable in the fuse box and retains the fuses for insertion and mating with the female member. However, one of the members must be rotatable to mate with the other section to act as a contact for the contact elements of the fuses and/or fuse holder. 
     In DeNigris et al. U.S. Pat. No. 4,052,688, a fuse clip assembly is arranged to accept alarm-type tubular fuses and has a terminal for applying forward pressure on the fuses and for capturing an extended alarm terminal. This particular fuse clip mounting board is generally utilized with a plurality of fuses and does not provide a housing or assembly for retaining a fixed number of fuses in an alignment for rapid insertion and removal within multiple circuit lines. 
     All of the above apparatus provide large-assembly fuse arrangements for utilization in applications where working area or space is generally without limitation. The components in these assemblies, particularly the fuses, are relatively large and bulky and not readily adaptable to structurally constricted electronic circuits. As an example, recently promulgated specifications by testing organizations and proposed rules from standards-setting engineering groups have placed a requirement on telecommunications networks requiring fusing therein. These networks are very compact as are their components, which has driven the movement to provide compact fuse and component arrangements which must also lend themselves to ease of assembly. Therefore, in present applications where space is a critical element and miniaturized or compact assemblies are demanded, fuse apparatus are required to contribute to the space-saving trend and adapt to confined spaces while providing the same blade contact and electrical power service capability. 
     SUMMARY OF THE INVENTION 
     The present apparatus provides a fuse carrier for cross-connecting at least two circuits in a terminal arrangement and particularly provides a small, compact insulator housing for the offset mounting of at least two cartridge-type electronic components, such as fuses, diodes, resistors and capacitors, with extending blade contacts protruding from the housing for coupling or joining circuits in a circuitboard or panel arrangement. Although these components can be mounted in conventional holders, space constraints will not permit utilization of these fuse holders in limited-space terminal panels or blocks. 
     An insulating housing is provided with dual tubular or cylindrical-type electronic components, which are offset-mounted in the housing to accommodate the cylindrical shapes and formed end members of the components in as tight a configuration as allowable without contact between the aligned components. In a preferred embodiment, the extending blade-type contacts protruding from fuse ends are coined to offset their centerline from the fuse body centerline, which locates the fuses as close as possible to the opposed housing walls and each other while maintaining the fuse-contact blade centerline along a longitudinal axis for side-by-side mounted fuses. The contact blades extend through aligned slits in the housing end walls, which prohibit fuse rotation as well as maintaining the offset fuse centerline position. A cover plate with extending platforms at either end of the housing is mounted on the housing to encapsulate the fuses, and to nest the contact blades on either side of a platform protuberance, which maintains contact blade location and separation for insertion into a circuit or panel board. Therefore, a fused arrangement, such as in a surge-protector, for ready insertion between terminal block circuits is provided in an insulated housing with the centerlines of the contact blades extending along the same centerlines as fuses provided in an adjacent, side-by-side fuse alignment The contact blades and fuses are insertable in extant circuitboards, but are provided in a more narrow and compact package. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the Figures of the drawing, like reference numerals identify like components, and in the drawings: 
     FIG. 1 is an elevational view of the fuse holder assembly; 
     FIG. 2 is a top plan view of the fuse holder assembly of FIG. 1; 
     FIG. 3 is a plan view taken along the lines 3--3 of FIG. 1; 
     FIG. 4 is an elevational side view of the assembly in FIG. 1, taken along the line 4--4; 
     FIG. 5 is a plan view of a fuse in FIG. 3; and, 
     FIG. 6 is an elevational view of a fuse as shown in FIG. 5. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     A compact electronic component holder, operable in a terminal block and having particular application for the cross-connection of two rows of terminals, is provided in the present invention. This arrangement overcomes space limitations as well as providing an apparatus operable with the structural arrangement of extant panels or circuit assemblies, which panels have contact positions juxtaposed in a generally predetermined configuration. The component sizes utilized are consistent with present applications, thereby eliminating the necessity for altering electrical components or their capacity specification, while still reducing the volume occupied by the housing and component assembly. 
     The above-noted electronic component holder may find application with any of the above-noted or other electrical components utilized in electrical circuits, especially those components with a single enlarged end or a dumbbell-shaped structure. However, the invention will be particularly described with reference to a fuse structure encompassing a generally cylindrical body with enlarged endcaps and extending blade-like contacts or electrical coupling in a circuit. 
     In a preferred embodiment, a fuse carrier or current-surge protector 10 is illustrated in the Figures and in FIGS. 1 and 3 are a housing 12 and a cover 14 mounted on housing 12, which cover 14 includes a first platform 16 at one end of the cover and a second platform 18 at the other end thereof. Cover 14 is positioned on housing 12 to enclose a cavity or chamber 20 in housing 12 and encase first and second fuses 22 and 24 therein. 
     Fuses 22, 24 are similar elements and, therefore, only one of the fuses will be described but the description is also applicable to the other fuse. As noted in FIGS. 3, 5 and 6, fuse 22 is a tubular or cylindrical body 26 with a first end 25 and a second end 27, and having a first end cap 28 and a second end cap 30, respectively, mounted on ends 25, 27, which end caps have larger diameters than body 26 and radially protrude from longitudinal axis 34 of body 26. As noted in the Figures, end cap 28 has a first contact blade 32 extending therefrom along blade axis 3 and generally parallel to longitudinal axis 34 of tubular body 26. A second contact blade 36 extends parallel to first or fuse body longitudinal axis 34, from second end 30 of fuse 22. In FIGS. 3, 5 and 6, blades 32, 36 are rectangularly-shaped and protrude approximately an equal length from housing end walls 40, 46, but first contact blade 32 is, in fact, shorter than second contact blade 36. 
     As shown in FIGS. 3, 5 and 6, fuse blades 32 and 36 on second or blade longitudinal axis 33 are coined in an offset fashion to provide the blades parallel to, but offset from, the longitudinal axis 34 of tubular body 26. In the Figures, blade 32 and end cap 28 merge in a truncated cone 70 with a first plateau or shoulder 72. Similarly, second contact blade 36 has a similar, generally truncated conical portion 74 with a second plateau or shoulder 76 at its intersection with second end 30 of fuse 22. 
     In a preferred embodiment, housing 12 has first end wall 40 with first blade passage 42 and second blade passage 44 therein, which blade passages are vertically elongated slits, as oriented in FIG. 1, and have a generally rectangular cross section. Similarly, second end wall 46 has third passage 48 and fourth passage 50 therein, with a similar rectangular, cross section. First sidewall 52 and second sidewall 54 of housing 12 are approximately parallel, as are end walls 40, 46; and as shown in FIG. 3, first and third passages 42, 48 are generally aligned, as are second and fourth passages 44, 50. 
     In FIG. 3, first sidewall 52 has a first inner surface 56 extending from second end wall 46, and a second segment or portion 58 extending into cavity 20 from first end wall 40. First and second inner surface portions 56 and 58 intersect at a first shoulder 60 in cavity 20. As shown, the wall thickness of second segment 58 is greater than the wall thickness of first segment 56. Similarly, second sidewall 54 has a first inner surface 62 and second inner surface 64 extending from first end wall 40 and second end wall 46, respectively, to intersect and provide a second shoulder 66 at their intersection. As shown in FIG. 3, the shoulders 60 and 66 are generally diagonally arranged in the approximately rectangular cavity 20 of housing 12. 
     First tubular fuse 22 is positioned in cavity 20 with second end cap 30 abutting first housing shoulder 60; first plateau 72 of first truncated end 70 abuts or is in proximity to second end wall inner face 45; and, contact blades 32 and 36 extend through aligned passages 48 and 42, respectively, to retain fuse 22 in position in cavity 20 against longitudinal or rotational movement. Similarly, second end cap 30 of second fuse 24 is provided generally against second shoulder 66 in cavity 20 with first plateau 72 of first truncated end 70 abutting or in proximity to first end wall inner face 43. Thus, the bodies 26 of the first and second fuses 22, 24 are generally aligned in parallel in cavity 20 and inhibited against longitudinal movement, but end caps 28, 30 of each fuse are offset to accommodate their protruding diameters, thus minimizing the space requirement within the cavity 20 and minimizing the required width of surge protector 10. 
     In FIG. 3, contact blade 32 of first fuse 22 extends through passage 48 and second contact blade 36 of fuse 22 extends through aligned passage 42 in first end wall 40. The first, second, third and fourth end elongated passages 42, 44, 48 and 50 with their generally rectangular cross section and extending contact blades therein, are operable to restrain or prohibit rotation of tubular fuses 22, 24 in housing 12. In this configuration, fuses 22 and 24 are secured in position in cavity 20 against movement along or rotation about fuse axes 34. 
     First and second platforms 16, 18 have a generally U-shaped profile, as shown in FIG. 1. Platforms 16, 18 are generally symmetrical and, therefore, only one platform and coupling means will be described but the description will be equally applicable to the other. As shown in FIGS. 1 and 2, first platform 16 extends from first end wall 40 and cover 14, and has a first leg 80, a second leg 82 with an end face 83. A first and second knuckle or joining base strap 84, 85 with separating gap 87 therebetween connect first and second legs 80 and 82. In FIGS. 1 and 2, leg 80 extends vertically normal from cover 14 and the straps or legs 80 and 82 are generally parallel, with a void or first gap 86 therebetween. Second leg 82 terminates at planar surface 90, as shown in FIGS. 1, 2 and 4, and has a downwardly-extending upright 88. The intersection of upright 88, which is about centrally located on surface 90, with leg 82 at surface 90 provides a first ledge 91 and a second ledge 92 on either side of this intersection. In FIGS. I and 4, contact blades 32 and 36 extend from housing 12, across gap 86 with their ends 94 and 96 resting against ledges 92, 91, respectively, and separated by upright 88. The blade ends extending from housing 12 and contacting platform 16 are similarly arranged on the ledges 91, 92. 
     In FIGS. 1 and 2, cover 14 has outer surface 17 and inner surface 19 With an outer edge, which inner surface 19 has a recess 21. A pair of tabs 23 extend from inner surface 19, although only one tab is noted in FIG. 1, at its outer edge, and are matable with locating bores 55, 57 in sidewalls 52, 54 (cf. FIG. 3) of housing 12 to position cover 14 on housing 12 to receive fuses 22, 24 in recess 21. Tabs 23 are preferably diagonally located on cover inner surface 19 and locating bores 55, 57 are similarly diagonally located on second segments 58, 64 of sidewalls 52, 54, which are illustrated as the thicker sidewall sections. 
     A gripping tab or tong 98 extends from cover assembly 14 to give the user a purchase or grip for handling and insertion of the surge protector. Cover 14 may be secured to housing 12 by means in the art, including adhesives, heat bonding, or mechanical apparatus such as screws. Housing 12 and cover 14 of surge protector 10 are an insulating material, such as plastic, and may be manufactured by rapid injection molding processes. 
     In the Figures, fuse-contact blades 32, 36 extend from either end of housing 12 to rest against the upright 88 and provide a contact area in gap or separation 86 at either end of surge protector 10 for insertion into a terminal or panel. This is the case for both first and second fuses 22, 24. In the configuration of housing 12 and platforms 16, 18, the fuses are retained in position against both rotation and longitudinal movement. 
     As seen in the Figures, first and second fuses 22, 24 are electrically isolated within the insulator housing 12, although they may be connected externally. The surge protector 10 is thus readily insertable in a circuit or on a panel board, which may have a plurality of input and output ports, to connect two circuits with fuses 22, 24. However, housing 12 insulates fuses 22, 24 from external contacts and provides the blades in a mechanically supported position against ledges 91, 92 of platforms 16, 18, which maintains the blades from deflection during insertion with the mating terminal contacts. In addition, the rectangular blades 32, 36 are restrained from rotation, and thus misalignment, in cavity 20 by the elongate passages 42, 44, 48, 50. Thus, surge protector 10 can be readily inserted into mating terminal contacts by gripping tab 98 with the knowledge that contact blades 32, 36 are aligned for insertion. 
     Further, the contact blades 32, 36 may be offset to reposition them along an axis for normally side-by-side mounted fuses, which accommodates the present terminal position in many known terminal blocks. 
     It is particularly noted in the above example that the fuse contacts are blades. The more general extending contact structure from an electrical component is a single round wire extending from each end. However, in the present invention these wire leads have been coined to provided the blade configuration in the drawings, which blade structure enhances the component stability in the carrier or housing by limiting rotation of the individual component; displaces the component centerline to allow both longitudinally and laterally offset the component within the carrier; and, does not alter the lead size in a manner to affect the resistance or electrical response of the component. 
     Although the above-noted preferred embodiment particularly related to a fuse holder housing, it is understood that the housing and offset component alignment are equally adaptable to other electronic components. As an example, barbell or hourglass shaped capacitors and resistors could also be secured and electrically isolated in the housing for insertion into a circuit, in a manner similar to the fuses. 
     While only specific embodiments of the invention have been described and shown, it is apparent that various alterations and modifications can be made therein. It is, therefore, the intention in the appended claims to cover all such modifications and alternations as may fall within the scope and spirit of the invention.