Rotation sensor

1. A rotation sensor for detecting rotation of a rotating body, comprising:

a case comprising:

a bottom surface portion provided at a distance from a surface of the rotating body; and

a side surface portion connected to the bottom surface portion so as to define a hollow internal space in cooperation with the bottom surface portion,

the case having an opening spatially connected to the hollow internal space, which is formed in the side surface portion on a side opposite to the bottom surface portion;

a plurality of lead frames respectively having distal ends inserted into the case through the opening;

a magnetic detection section provided to the distal ends of the plurality of lead frames arranged in parallel, for detecting a change in magnetic field of a magnetic body provided to the rotating body;

a spacer provided between the plurality of lead frames and the side surface portion so as to be held in contact with an internal wall surface of the side surface portion; and

an internal filling resin for filling a space portion of the hollow internal space except for the spacer, the magnetic detection section, and the plurality of lead frames,

wherein:

each of the plurality of lead frames has a positioning hole; and

the spacer comprises positioning pins each being inserted into the positioning hole.

2. A rotation sensor according to claim 1 , wherein a pair of the spacers are provided so as to be opposed to each other through the plurality of lead frames therebetween.

3. A rotation sensor according to claim 1 , wherein the spacer comprises fitting means for fitting the spacer and the magnetic detection section to each other between the spacer and the magnetic detection section.

4. A rotation sensor according to claim 1 , wherein the spacer comprises a rib projecting into a gap between the plurality of adjacent lead frames so as to ensure the gap.

5. A rotation sensor according to claim 1 , wherein the spacer comprises positioning pins projecting so as to interpose both sides of each of the plurality of lead frames.

6. A rotation sensor according to claim 1 , further comprising a positional alignment portion for positional alignment between the case and the spacer, the positional alignment portion being provided between the side surface portion of the case and the spacer.

7. A rotation sensor according to claim 1 , wherein the bottom surface portion of the case has a shape corresponding to a shape of the magnetic detection section.

8. A rotation sensor for detecting rotation of a rotating body, comprising:

a case comprising:

a bottom surface portion provided at a distance from a surface of the rotating body; and

a side surface portion connected to the bottom surface portion so as to define a hollow internal space in cooperation with the bottom surface portion,

the case having an opening spatially connected to the hollow internal space, which is formed in the side surface portion on a side opposite to the bottom surface portion;

a plurality of lead frames respectively having distal ends inserted into the case through the opening;

a magnetic detection section provide to the distal ends of the plurality of lead frames arranged in parallel, for detecting a change in magnetic field of a magnetic body provided to the rotating body;

a spacer provided between the plurality of lead frames and the side surface portion so as to be held in contact with an internal wall surface of the side surface portion; and

an internal filling resin for filling a space portion of the hollow internal space except for the spacer, the magnetic detection section, and the plurality of lead frames,

wherein:

a pair of the spacers are provided so as to be opposed to each other through the plurality of lead frames therebetween;

each of the plurality of lead frames has a positioning hole;

one of the pair of spacers comprises a positioning pin to pass through the positioning hole; and

another of the pair of spacers comprises a positioning hole opposed to the positioning pin.

9. A rotation sensor for detecting rotation of a rotating body, comprising:

a case comprising:

a bottom surface portion provided at a distance from a surface of the rotating body; and

a side surface portion connected to the bottom surface portion so as to define a hollow internal space in cooperation with the bottom surface portion,

the case having an opening spatially connected to the hollow internal space, which is formed in the side surface portion on a side opposite to the bottom surface portion;

a plurality of lead frames respectively having distal ends inserted into the case through the opening;

a magnetic detection section provided to the distal ends of the plurality of lead frames arranged in parallel, for detecting a change in magnetic field of a magnetic body provided to the rotating body;

a spacer provided between the plurality of lead frames and the side surface portion so as to be held in contact with an internal wall surface of the side surface portion; and

an internal filling resin for filling a space portion of the hollow internal space except for the spacer, the magnetic detection section, and the plurality of the lead frames,

wherein:

a pair of the spacers are provided so as to be opposed to each other through the pluarlity of lead frames therebetween;

one of the spacers comprises a spacer convex-side fitting portion;

another of the spacers comprises a spacer concave-side fitting portion formed so as to be opposed to the spacer convex-side fitting portion;

each of the plurality of lead frames comprises a lead-frame interposing portion formed on a side of an end portion thereof, which is closer to an adjacent one of the plurality of lead frames; and

the spacer convex-side fitting portion and the lead-frame interposing portion are fitted into the spacer concave-side fitting portion.