Motor shaft discharge device

Apparatus for electrically discharging a rotating shaft of a machine, said apparatus comprising:

• contact means for providing a durable, contamination free, electrical contacting surface, said contact means being coupled for rotation with said shaft while being electrically connected thereto;
• a conductive brush for resiliently and continuously contacting said surface of said contact means during rotation thereof;
• and
• a housing for slidably receiving said conductive brush in juxtaposition with said contact means so the brush can engage said contact means, said housing providing means cooperating to substantially enclose the region of contact between said contact means and said brush for isolating said region from the machine and the environment, said housing including means forming a circuit path for coupling said brush to the frame of said machine so as to complete a discharge circuit for said shaft;
• said apparatus defining a cavity for extending the immediate enclosed region of contact between said contact means and said brush for the purpose of receiving and holding residue produced by said brush as said shaft rotates;
• wherein said housing is secured to said machine and is substantially closed except for passage of said shaft carrying said contact means;
• wherein said contact means is supported from the end of said shaft and is cup shaped, being open ended in the direction axially away from said machine, said brush extending from said housing into the open end of the cup-shaped contact means for contacting the inner end of the contact means closest to said machine, and further including an elastomeric ring in surrounding relation to said brush and compressed from said housing toward the open edge of the cup-shaped contact means, said cup-shaped contact means cooperating to provide said cavity;
• wherein said cup-shaped contact means has a substantially cylindrical interior, said brush being positioned in parallel relation to the axis of said cylindrical interior and said shaft but having a contacting tip offset with respect to said axis to engage the inner end of said contact means between said axis and the cylindrical interior wall of said contact means;
• and
• wherein said housing includes a cylindrical member slidably positionable in said housing and in turn slidably receiving said conductive brush, said elastomeric ring being compressed between said cylindrical member and the open edge of said cup-shaped contact means.

Apparatus for electrically discharging a rotating shaft of a machine, said apparatus comprising:

• contact means for providing a durable, contamination free, electrical contacting surface, said contact means being coupled for rotation with said shaft while being electrically connected thereto;
• a conductive brush for resiliently and continuously contacting said surface of said contact means during rotation thereof;
• and
• a housing for slidably receiving said conductive brush in juxtaposition with said contact means so the brush can engage said contact means, said housing providing means cooperating to substantially enclose the region of contact between said contact means and said brush for isolating said region from the machine and the environment, said housing including means forming a circuit path for coupling said brush to the frame of said machine so as to complete a discharge circuit for said shaft;
• said apparatus defining a cavity for extending the immediate enclosed region of contact between said contact means and said brush for the purpose of receiving and holding residue produced by said brush as said shaft rotates;
• wherein said housing is secured to said machine and is substantially closed except for passage of said shaft carrying said contact means;
• wherein said contact means comprises a cylindrical member secured to said shaft, said housing being provided with a first bore for receiving said brush, said first bore extending radially toward the outer cylindrical surface of said cylindrical member, and a second bore for providing said cavity;
• and
• wherein said housing is oriented on said machine with said first bore extending vertically downwardly toward said cylindrical extension member, said second bore extending vertically below said cylindrical extension member, and said second bore having a removable plug for withdrawing said residue.

Apparatus for electrically discharging a rotating shaft of a machine, said apparatus comprising:

• contact means for providing a durable, contamination free, electrical contacting surface, said contact means being coupled for rotation with said shaft while being electrically connected thereto;
• a conductive brush for resiliently and continuously contacting said surface of said contact means during rotation thereof;
• and
• a housing for slidably receiving said conductive brush in juxtaposition with said contact means so the brush can engage said contact means, said housing providing means cooperating to substantially enclose the region of contact between said contact means and said brush for isolating said region from the machine and the environment, said housing including means forming a circuit path for coupling said brush to the frame of said machine so as to complete a discharge circuit for said shaft;
• said apparatus defining a cavity for extending the immediate enclosed region of contact between said contact means and said brush for the purpose of receiving and holding residue produced by said brush as said shaft rotates;
• wherein said housing is juxtaposed with respect to said machine and is substantially cylindrical, being further adapted for juxtaposition with the face of a second machine located at the side of said housing remote from the first mentioned machine;
• said housing having a cylindrical aperture for receiving said shaft extending between said machines;
• said contact means comprising a cylindrical member received upon said shaft within said cylindrical aperture;
• said housing being provided with a first radial bore for receiving said brush in contacting relation with the outer cylindrical surface of said contact means and a second bore for providing said cavity.

Apparatus for electrically discharging a rotating shaft of a machine, said machine having a frame supporting bearings journalling said shaft,

• the end of said shaft having a contacting surface,
• said apparatus including means for holding a conductive brush in resilient and continuous frictional contact with said contacting surface at said end of said shaft so as to provide a continuous frictional contact with said contacting surface to provide a continuous electrical discharge path for said shaft for shunting transients to frame ground as would otherwise appear across said bearings and damage said bearings,
• wherein said holding means urges said brush in a direction substantially longitudinal of said shaft toward said contacting surface,
• said contacting surface being provided by a contact means supported from the end of said shaft, said contact means being cup-shaped and open ended in the direction axially away from said machine, said brush extending into the open end of the cup-shaped contact means for contacting the inner end of the contact means.

Apparatus for electrically discharging a rotating shaft of a machine, said apparatus comprising:

• contact means for providing a durable, contamination free, electrical contacting surface, said contact means being coupled for rotation with said shaft while being electrically connected thereto;
• a conductive brush for resiliently and continuously contacting said surface of said contact means during rotation thereof;
• and
• a housing for slidably receiving said conductive brush in juxtaposition with said contact means so the brush can engage said contact means, said housing including means forming a circuit path for coupling said brush to the frame of said machine so as to complete a discharge circuit for said shaft;
• said apparatus defining a cavity for extending the immediate region of contact between said contact means and said brush for the purpose of receiving and holding residue produced by said brush as said shaft rotates;
• and
• wherein said contact means is supported from the end of said shaft and is cup shaped, being open ended in the direction axially away from said machine, said brush extending from said housing into the open end of the cup-shaped contact means for contacting an inner end of the contact means closest to said machine, and further including an elastomeric ring in surrounding relation to said brush and compressed toward said cup-shaped contact means, said cup-shaped contact means cooperating to provide said cavity.