Electric junction box

1. An electric junction box comprising:

a box body that includes a plurality of outer walls and a mounting hole defined by the outer walls;

a cassette block received in the mounting hole, the cassette block corresponding to a single body, the cassette block including terminal-receiving chambers and a plurality of pairs of grooves that are opposed to each other, at least one of said pairs of grooves being formed hollow from upper end parts of mutually facing side walls of one of said terminal-receiving chambers of the cassette block, the at least one of said pairs of grooves extending through the mutually facing side walls of the one of said terminal-receiving chambers, wherein the mutually facing side walls are side walls of the single body;

a plurality of relays configured to be mounted on an upper side of the cassette block; and

a plurality of ribs in a bar shape that extend straight from one inner wall surface of the mounting hole of the box body, and continue to and contact with an opposite inner wall surface of the mounting hole, said ribs being in one piece with the inner wall surfaces such that a space is provided under an underside of the ribs so as to receive the cassette block in the box body, said ribs configured to be at a position between the relays mounted on the upper side of the single body of the cassette block and to enter at least one pair of the grooves of the cassette block such that rigidity of the box body is imparted and distortion of the box body is prevented.

2. The electric junction box according to claim 1 , wherein the ribs are arranged at a position between the relays adjacent to each other out of a plurality of the relays mounted in the cassette block.

3. The electric junction box according to claim 1 , wherein the grooves are formed on a surface of the cassette block.

4. The electric junction box according to claim 2 , wherein the grooves are formed on a surface of the cassette block.

5. An electric junction box comprising:

a box body that includes a plurality of outer walls and a mounting hole defined by the outer walls;

a cassette block received in the mounting hole, the cassette block corresponding to a single body, the cassette block including terminal-receiving chambers and a plurality of pairs of grooves that are opposed to each other, at least one of said pairs of grooves being formed hollow from upper end parts of mutually facing side walls of one of said terminal-receiving chambers of the cassette block, wherein the mutually facing side walls are side walls of the single body;

a plurality of relays configured to be mounted on an upper side of the single body of the cassette block; and

a plurality of ribs in a bar shape that extend straight from one inner wall surface of the mounting hole of the box body, and continue to and contact with an opposite inner wall surface of the mounting hole, said ribs being in one piece with the inner wall surfaces such that a space is provided under an underside of the ribs so as to receive the cassette block in the box body, said ribs configured to be at a position between the relays mounted on the upper side of the single body of the cassette block and to enter at least one pair of the grooves of the cassette block such that rigidity of the box body is imparted and distortion of the box body is prevented, wherein at least one of said ribs extends into the mounting hole.

6. The electric junction box according to claim 5 , wherein the ribs are arranged at a position between the relays adjacent to each other out of a plurality of the relays mounted in the cassette block.

7. The electric junction box according to claim 5 , wherein the grooves are formed on a surface of the cassette block.

8. The electric junction box according to claim 6 , wherein the grooves are formed on a surface of the cassette block.