Junction box for a solar panel

• US 5,280,133 A
• Filed: 12/13/1991
• Issued: 01/18/1994
• Est. Priority Date: 12/13/1991
• Status: Expired due to Term

• Current Assignee: United Solar Systems Corp.
• Original Assignee: United Solar Systems Corp.
• Inventors: Nath, Prem
• Primary Examiner(s): Picard, Leo P.
• Assistant Examiner(s): LEDYNH, BOT L
• Application Number:
  US07/808,158
• Time in Patent Office: 767 Days
• Field of Search: 361/392, 361/394, 361/399, 361/419, 361/395, 174/52.1, 174/52.2, 136/251, 439/59, 439/60, 439/61, 439/62, 264/239, 264/271.1, 264/272.11
• US Class Current: 174/373
• CPC Class Codes: H01L 31/048 Encapsulation of modules
• CPC Class Codes: H01R 12/53 connecting to cables except for flat or ribbon cables
• CPC Class Codes: H01R 13/5213 Covers
• CPC Class Codes: H01R 13/5216 characterised by the sealing material, e.g. gels or resins
• CPC Class Codes: H01R 13/58 Means for relieving strain on wire connection, e.g. cord grip , for avoiding loosening of connections between wires and terminals within a coupling device terminating a cable for flat or ribbon cables H01R12/771
• CPC Class Codes: H02S 40/34 comprising specially adapted electrical connection means to be structurally associated with the PV module, e.g. junction boxes
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y10S 174/35 Box or housing mounted on substrate or PCB

Abstract

A solar panel assembly (10) includes a power generating sheet (22) having two output terminals (30,32), and an electric cable (20) soldered at one end to terminals (30) and (32). A frame member is anchored to the solar panel in overlying relation to the terminals and an epoxy material (62) fills a cavity (58) defined by the frame member (40). A case (42) covers the frame member (40). The case includes an upper member (44) and a lower member (46) which are snap fitted together through apertures in the solar panel. The case (42) includes a tension relieving device which prevents tension on the cable (20) from being transferred to the cable end connected to the terminals (30) and (32). The epoxy provides a water resistant seal which allows the solar panel to be used in hostile environments.

Claims

1. A junction box for use in establishing electric connection between an electric cable and output terminals of a solar panel located proximate one edge of the panel, said box comprising first and second separate box members adapted to respectively engage opposite faces of the panel proximate said one edge with the panel edge sandwiched therebetween and coacting when so engaged to define a passage through the box extending from an opening in the exterior of the box, sized to pass the electric cable, to a location proximate the panel terminals, said box members coacting with the panel when engaged with the panel to seal the passage except for said opening.

2. A box according to claim 1 wherein one of said members includes a plurality of posts and the other of said members includes a corresponding plurality of receptors sized to snappingly receive said posts, and said posts pass through holes in the solar panel for coaction with said receptors to snappingly secure the members against opposite faces of the panel.

3. A box according to claim 1 wherein the box further includes potting material filling a portion of said passage proximate the panel terminals and adapted to encase the portion of the cable proximate the terminals.

4. A junction box for use in establishing electric connection between an electric cable and output terminals of a solar panel located proximate one edge of the panel, said box comprising first and second box members adapted to engage opposite faces of the panel proximate said one edge with the panel edge sandwiched therebetween and coacting when so engaged to define a passage through the box extending from an opening in the exterior of the box, sized to pass the electric cable, to a location proximate the panel terminals, the box further including potting material filling a portion of said passage proximate the panel terminals and adapted to encase the portion of the cable proximate the terminals, said second box member engaging the lower face of the solar panel, said first box member engaging the upper face of the panel and defining a downwardly opening hollow overlying the panel terminals, said box further including a frame member having an enclosing border configuration and sized to fit within said hollow, and said epoxy filling the area overlying said terminals enclosed by said frame member.

5. A box according to claim 4 wherein said box further includes an anchor plate, said frame member and said anchor plate have coacting means for securing the frame member to the anchor plate with the frame member overlying the terminals and the anchor plate underlying the terminals.

6. A box according to claim 5 wherein said coacting means comprises downwardly extending posts on said frame member passing through apertures in said anchor plate.

7. A junction box for shielding the connection of an electric cable to output terminals of a solar panel positioned proximate an end edge portion of the solar panel, said junction box comprising:

a first case member;

a frame member, having an enclosing border configuration, received within said first case member and positioned against one face of the edge portion of the solar panel in overlying, surrounding relation to the output terminals of the solar panel;

an anchor plate positioned against an opposite face of the edge portion of the solar panel and secured to said frame member;

a second case member positioned against said opposite face of the edge portion of the solar panel and secured to said first case member to clamp the edge portion of the solar panel therebetween; and

means within said case members defining an electric cable passage extending from a location exteriorally of the junction box to a location within said frame member in overlying proximity to the terminals.

8. A junction box according to claim 7 wherein one of said first and second case members includes a tension relief device adapted to engage the electric cable and operative to preclude tension exerted on the electric cable exteriorally of the junction box from being transferred to the end of the cable connected to the terminals.

9. A junction box according to claim 8 wherein

one of said frame member and said anchor plate has posts that extend through the solar panel;

and

the other of said frame member and said anchor plate has receptors to receive said posts and thereby lock said frame member and said anchor plate together with the solar panel sandwiched therebetween.

10. A junction box according to claim 7 wherein one of said first and second case members has posts extending through the solar panel and the other of said first and second case members has receptors to receive said posts and thereby lock said first and second case members together with the solar panel sandwiched therebetween.

11. A junction box according to claim 7 wherein said first and second case members are coactingly configured to define an aperture for passage of the electric cable and are further coactingly configured to receive the end edge of the edge portion of the solar panel therebetween.

12. A low profile junction box for a flat solar panel having output terminals characterized in that the junction box includes first and second separate case members clamped about the flat solar panel;

the junction box has a combined height transverse to the plane of the solar panel that is substantially less than the length of the junction box measured transverse to the height of the box; and

the junction box closes about the output terminals of the solar panel and defines a passage therethrough to allow an electric cable connected to the output terminals to pass through the box to a location outside of the box, said case members coacting with said panel when clamped about the panel to seal the passage except for said opening.

13. A low profile junction box according to claim 12 wherein the first case member contains a sealant that is adapted to be placed over the electric connection of the electric cable to the output terminals.

14. A low profile junction box according to claim 13 wherein the box further includes a frame member, having an enclosing border configuration, mounted within the first case member for containing the sealant therein and the frame member is connected to an anchor plate positioned on an opposite side of the solar panel from the frame member.

15. A low profile junction box according to claim 12 wherein one of said first and second case members has a plurality of posts and the other of said first and second case members has a plurality of receivers for lockingly engaging the posts to clamp the first and second case members against opposite sides of the solar panel.

16. A low profile junction box according to claim 15 wherein the first and second case members have side walls that are coacting configured to accommodate an end edge portion of the solar panel therebetween.

17. A low profile junction box according to claim 12 wherein said case members define a tension relief device adapted to engage the electric cable and operative to preclude tension exerted on the cable outside of the junction box from being transferred to the end of the cable connected to the solar panel terminals.

18. A junction box according to claim 17 wherein said tension relief device includes means dividing said cable passage into first and second portions extending substantially at right angles to each other and means adapted to engage the cable at the turn in the cable between said first and second cable portions and operative to preclude the transfer of tension forces exerted on the first portion to the second portion.

19. A junction box for connecting the output terminals of a solar panel to an electric cable, said junction box comprising:

an anchor plate positionable on one side of the solar panel;

a frame member having an enclosing border configuration positionable on another side of the solar panel in opposition to said anchor plate;

means for affixing said frame member to said anchor plate with said solar panel sandwiched therebetween and with said frame member positioned in surrounding relation to the output terminals of the solar panel;

said frame member being constructed to retain a water sealing potting material therebetween that is adapted to encase the end of an electric cable connected to the output terminals of the solar panel; and

said frame having a passage in the border thereof to allow the electric cable to pass therethrough for connection to the output terminals of the solar panel.

20. A method of establishing a sealed connection between a solar panel having output terminals and an electric cable comprising the steps of:

connecting one end of the cable to the output terminals;

potting said one cable end in a quantity of potting material overlying and sealing said terminals; and

positioning a junction box over the potting material with the electric cable extending out of the junction box through an aperture in the junction box.

21. A method according to claim 20 wherein said potting step comprises placing a frame member having an enclosing border configuration over said output terminals with said one end of said cable extending into the area enclosed by the frame member for connection to the output terminals and placing said potting material within said frame member in surrounding relation to said one cable end.

22. A method according to claim 21 wherein said potting step further comprises placing an anchor plate beneath said output terminals and coupling said frame member to said anchor plate by coupling means passing through the solar panel in surrounding relation to said output terminals.