Terminal block and method of molding it

1. A terminal block for fastening conductors by placing the conductors one above another and fastening bolts, comprising a plurality of nuts on which the conductors are to be placed and a partition wall partitioning between the nuts adjacent to each other, the partition wall extending in a direction crossing an arrangement direction of the nuts and includes:

an insulation wall made of primary molding resin, located at least in a range in a vertical direction from the lower surfaces of the nuts to the upper surfaces of the bolts to be fastened to the nuts and insulating between the adjacent nuts,

a secondary molding made of secondary molding resin, filling up clearances between the insulation wall and the nuts and at least partly covering the side surface of the insulation wall, and

at least one projection projecting up from an upper end of the insulation wall and having an exposed portion exposed above an upper surface of the secondary molding.

2. The terminal block of claim 1 , wherein the secondary molding covers side surfaces of the insulation wall over substantially an entire periphery.

3. The terminal block of claim 1 , wherein a plurality of exposed portions are arranged in the direction crossing the arrangement direction of the nuts on the upper surface of the secondary molding.

4. The terminal block of claim 1 , wherein an incline is formed on the upper surface of the secondary molding and at least partly covering a base end of the exposed portion.

5. The terminal block of claim 4 , wherein the incline covers a base end portion of the exposed portion over an entire periphery.

6. The terminal block of claim 4 , wherein the incline is configured to follow deformation of the exposed portion to be held in close contact with the base end of the exposed portion when an external force acts on the exposed portion.

7. The terminal block of claim 1 , wherein a creepage distance between the adjacent nut accommodating recesses particularly is ensured by the insulation wall.

8. A terminal block for fastening conductors by placing the conductors one above another and fastening bolts, comprising a plurality of nuts on which the conductors are to be placed and a partition wall partitioning between the nuts adjacent to each other, the partition wall extending in a direction crossing an arrangement direction of the nuts and includes:

an insulation wall made of primary molding resin, located at least in a range in a vertical direction from the lower surfaces of the nuts to the upper surfaces of the bolts to be fastened to the nuts and insulating between the adjacent nuts,

a secondary molding made of secondary molding resin, filling up clearances between the insulation wall and the nuts and at least partly covering the side surface of the insulation wall,

a heat sink arranged on one side of the nuts opposite to a side where the conductors are to be placed, and

an insulation plate sandwiched between the nuts and the heat sink.

9. The terminal block of claim 8 , further comprising at least one projection projecting up from an upper end of the insulation wall and having an exposed portion exposed above an upper surface of the secondary molding.

10. The terminal block of claim 8 , wherein the secondary molding at least partly covers the nuts, the insulation plate and the heat sink.

11. The terminal block of claim 10 , wherein the secondary molding includes:

an upper cover held in close contact with the nuts and upper ends of surrounding walls of the insulation plate,

a lower cover held in close contact with a sink body of the heat sink, and

a side wall held in close contact with the outer side surfaces of the insulation plate and the sink body of the heat sink.

12. The terminal block of claim 11 , wherein the upper covering fills up the clearances between the inner peripheral surfaces of the surrounding wall of the nut accommodating recess and the side surface of the respective nut.

13. The terminal block of claim 11 , wherein the upper cover comprises surrounding wall coverings at least partly covering the upper surfaces of the surrounding walls.

14. A terminal block, comprising:

an insulation plate formed with a plurality of nut accommodating recesses arranged substantially side by side in an arrangement direction, at least one insulation wall extending substantially perpendicular to the arrangement direction and between the nut accommodating recesses that are adjacent to one another, the insulation wall having side surfaces facing into the adjacent nut accommodating recesses and a top surface, projections projecting up from the top surface of the insulation wall;

nuts accommodated respectively in the nut accommodating recesses so that clearances exist between the nuts and the insulation wall; and

a secondary molding made of secondary molding resin filling the clearances between the insulation wall and the nuts and at least partly covering the side surfaces and the top surfaces of the insulation wall so that the projections project up beyond the secondary molding.

15. The terminal block of claim 14 , wherein the projections on the insulation wall are spaced apart in a substantially linear array extending substantially perpendicular to the arrangement direction.

16. The terminal block of claim 15 , wherein the secondary molding defines inclined fillets between the upper surface of the insulation wall and the projections.

17. A method of making a terminal block, comprising:

providing an insulation plate formed with a plurality of nut accommodating recesses arranged substantially side by side in an arrangement direction, at least one insulation wall extending substantially perpendicular to the arrangement direction and between the nut accommodating recesses that are adjacent to one another, the insulation wall having side surfaces facing into the nut accommodating recesses and a top surface, projections projecting up from the top surface of the insulation wall;

placing nuts in the respective nut accommodating recesses so that clearances exist between the nuts and the insulation wall;

closing molds around the insulation plate and the nuts so that one of the molds receives top ends of the projections of the insulation wall for securely positioning the insulation wall; and

injecting a secondary molding resin between the molds to form a secondary molding filling the clearances between the insulation wall and the nuts and at least partly covering the side surfaces and the top surface of the insulation wall and base ends of the projections adjacent the top surface of the insulation wall.