Apparatus for starting and protecting of electrical motors

Claim 2

Combined motor protector and relay apparatus comprising: a base; a first stationary contact mounted on said base, a first thermal element comprising a snap acting disc mounted on the base and adapted to move into nd out of engagement with the first stationary contact; a second stationary contact mounted on the base, a second thermal element comprising a creep acting blade mounted on the base and adapted to move into and out of engagement with the second stationary contact; heating means located in the base in heat transfer relation with both the first and second thermal elements; and means to provide electrical connection for the thermal elements, stationary contacts and heater with the second thermal element adapted to deenergize the start winding of a motor and the first thermal element adapted to deenergize the apparatus.

Claim 3

Apparatus according to claim 1 in which the heating means comprises a single heating element.

Claim 4

Apparatus according to claim 1 in which the snap acting disc moves toward the heating means when moving out of engagement with the first stationary contact and the creep acting blade moves away from the heating means when moving out of engagement with the second stationary contact.

Claim 5

Apparatus according to claim 1 in which both the snap acting disc and the creep acting blade move toward the heater when moving Out of engagement with respective first and second stationary contacts.

Claim 6

Apparatus according to claim 2 in which the means to provide electrical connection includes electrically connecting the heater element serially between the first thermal element and the second thermal element.

Claim 7

Apparatus according to claim 2 including a shunt heater electrically connected from the second stationary contact across the second thermal element.

Claim 8

Apparatus for starting and protecting electrical equipment having a main winding and an auxiliary winding comprising: a base formed of electrically insulative material with a switch cavity defined therein and having at least three apertures extending from without the base into the switch cavity; a first terminal received in one of the apertures, a first stationary contact provided on the first terminal located within the switch cavity, a snap acting disc cantilever mounted on the base within the switch cavity and having a free distal end, a first movable contact mounted on the free distal end of the disc and adapted to move into and out of engagement with the first stationary contact; a second terminal received in another one of the apertures, a second stationary contact provided on the second terminal located within the switch cavity, a third terminal received in another one of the apertures and having a portion located within the switch cavity, a creep acting blade cantilever mounted on the portion of the third terminal and having a free distal end, a second movable contact mounted on the free distal end of the blade and adapted to move into and out of engagement with the second stationary contact; an electrical resistance heater having two ends, one end electrically connected to the disc and the other end electrically connected to the third terminal, the heater being positioned so that it is in heat transfer relation with both the disc and the blade; and a cover enclosing the switch cavity, the first terminal connectable to a power source, the second terminal connectable to the auxiliary winding and the third terminal connectable to the main winding.

Claim 9

Apparatus for starting and protecting electrical equipment having a main winding and an auxiliary winding comprising: a base formed of electrically insulative material with a switch cavity defined therein and having at least three apertures extending from without the base into the switch cavity; a first terminal received in one of the apertures, a first stationary contact provided on the first terminal located within the switch cavity, a snap acting disc cantilever mounted on the base within the switch cavity and having a free distal end, a first movable contact mounted on the free distal end of the disc and adapted to move into and out of engagement with the first stationary contact; a second terminal received in another one of the apertures, a second stationary contact provided on the second terminal located within the switch cavity, a third terminal received in another one of the apertures and having a portion located within the switch cavity, a creep acting blade cantilever mounted on the portion of the third terminal and having a free distal end, a second movable contact mounted on the free distal end of the blade and adapted to move into and out of engagement with the second stationary contact; an electrical resistance heater having two ends, one end electrically connected to the disc and the other end electrically connected to the third terminal, the heater being positioned so that it is in heat transfer relation with both the disc and the blade; and a cover enclosing the switch cavity, the first terminal connectable to a power source, the second terminal connectable to the auxiliary winding and the third terminal connectable to the main winding.

Claim 10

Apparatus according to claim in which the snap acting element and the creep acting blade are positioned side by side and lie in respective parallel planes.

Claim 11

Apparatus according to claim 9 in which a first portion of the heater is positioned intermediate the cover and the snap disc and a second portion of the heater is positioned intermediate the base and the blade.

Claim 12

Apparatus according to claim 8 in which a raised platform is provided in the base on which the creep acting blade is mounted, a groove is defined in the platform running in a direction transversely to the blade and communicates with one of the apertures in the base, the third terminal forms a first leg and extends through the aperture in communication with the groove and depends from a body portion received in the groove, a second leg extends from the body portion parallel to the platform surface on which leg the blade is cantilever mounted, and a third leg extends from the body portion parallel to the platform surface but in an opposite direction to that of the second leg, an end of the heater element being attached to the third leg.

Claim 13

Apparatus according to claim 8 in which the base is generally rectangular in plan view and includes upstanding projections extending from the base on at least two diametrically opposite corners to provide protection for the parts mounted in the switch cavity.

Claim 14

Apparatus according to claim 8 in which a fourth aperture is defined in the base, an eyelet is received in the aperture, and a splined stud mounting the disc is telescopically received in the eyelet.

Claim 15

Apparatus according to claim 8 in which a first portion of the heater is located intermediate the creep acting blade and the cover and a second portion of the heater is located intermediate the snap acting blade and the cover.

Claim 16

Apparatus according to claim 14 in which a shunt heateR is connected between the first terminal and the third terminal and is intermediate the blade and the base.

Claim 17

Apparatus according to claim 8 in which a projection extends downwardly from the cover and terminates at a position to limit the opening movement of the free distal end of the snap acting blade.

Claim 18

Apparatus according to claim 8 in which the creep acting blade is generally trapezoidal in shape extending from a rectangular mounting tab and the snap acting blade is generally rectangular in shape and is a fully formed disc.