Electric motor contact member protector
First Claim
1. An electric motor comprising:
- a commutator having a plurality of contact members made of carbon and electrically isolated from each other and a supporting member for supporting said plurality of contact members;
an armature having a rotary shaft, wherein said commutator is coaxially fixed at one end thereof, said armature being molded in a resin;
a pair of brushes biased along said rotary shaft by a resilient member on said plurality of contact members of said commutator; and
a brush holder axially opposed to said commutator of said armature, for rotatably holding said rotary shaft and holding said brushes movably along the axial direction, wherein a limiter structure limiting movement of said armature toward said brush holder in the axial direction is formed in at least either of said brush holder or said armature to provide a clearance between said contact members and said brush holder when the movement of said armature is stopped by said limiter structure.
1 Assignment
0 Petitions
Accused Products
Abstract
An electric motor provides a carbon contact member of a commutator from colliding with a brush holder. A projection is formed in the brush holder so that it projects toward an end face of a resin mold of an armature. An end face of this projection, which is opposed to the end face of the resin mold of the armature, is positioned in the axial direction so as to form a clearance between the contact members and the brush holder when the armature is moved toward the brush holder by an external force and the end face comes in contact with the end face. As a result, if shock is applied to the fuel pump and the armature moves toward the brush holder, the contact members of the commutator are prevented from colliding with the brush holder. It thereby becomes possible to prevent the carbon contact members from being damaged.
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Citations
16 Claims
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1. An electric motor comprising:
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a commutator having a plurality of contact members made of carbon and electrically isolated from each other and a supporting member for supporting said plurality of contact members;
an armature having a rotary shaft, wherein said commutator is coaxially fixed at one end thereof, said armature being molded in a resin;
a pair of brushes biased along said rotary shaft by a resilient member on said plurality of contact members of said commutator; and
a brush holder axially opposed to said commutator of said armature, for rotatably holding said rotary shaft and holding said brushes movably along the axial direction, wherein a limiter structure limiting movement of said armature toward said brush holder in the axial direction is formed in at least either of said brush holder or said armature to provide a clearance between said contact members and said brush holder when the movement of said armature is stopped by said limiter structure. - View Dependent Claims (2, 3, 4, 5)
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6. An electric motor comprising:
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a planar commutator having a plurality of contact members that are made of carbon and electrically isolated from each other;
a supporting member for supporting said plurality of contact members;
an armature having a rotary shaft and said commutator coaxially fixed at one end thereof, said armature being molded in a resin;
a pair of brushes biased along said rotary shaft by a resilient member on said plurality of contact members of said commutator; and
a brush holder axially opposed to said commutator of said armature, for rotatably holding said rotary shaft and holding said brushes movably along the axial direction, wherein a limiter structure limiting movement of said armatur toward said brush holder in the axial direction is formed in at least either of said brush holder or said armature to meet a condition, L1<
L2, where L1 is a distance between said limiter structure and the opposing contact face and L2 is a distance between the contact member of said commutator and the opposing face of said brush holder.
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7. An electric motor comprising:
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a commutator having a plurality of contact members;
a supporting member for supporting said plurality of contact members;
an armature having a rotary shaft, wherein said commutator is coaxially fixed at a first end of the rotary shaft;
a pair of brushes adjacent to said first end of said rotary shaft and biased by a resilient member at one end of said plurality of contact members of said commutator; and
a brush holder axially opposed to said commutator of said armature, for rotatably supporting said rotary shaft and movably supporting said brushes parallel to the rotary shaft; and
a limiter structure which limits movement of said armature in the armature'"'"'s axial direction so that said contact members do not make contact with said brush holder when said armature moves toward said brush holder. - View Dependent Claims (8, 9, 10, 11, 12, 13, 14, 15, 16)
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Specification