US1792299A

US1792299A - Thermal cut-out

Info

Publication number: US1792299A
Application number: US445492A
Authority: US
Inventors: Adoniram J Green
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1930-04-18
Filing date: 1930-04-18
Publication date: 1931-02-10
Anticipated expiration: 1948-02-10

Description

994M644 HLs Attowney.v

Feb. 10, 1931. A. J. GREEN THERMAL CUT-OUT F'i1ed April l8. 1950 Patented Feb. 10, '1931 UNITED STATES PATENT OFFICE ADONIBAM J. GREEN, 0] WEST CALDWELL, NEW JERSEY, ASSIGNOR TO GENERAL ELECTRIC COMPANY A CORPORATION \OF NEW YORK THERMAL CUT-OUT Application filed April 18,

My invention relates to thermal cutouts, particularly of the fusible link type such as shown and claimed in the Wright atent No. 1,265,576, of May 7, 1918.

In the Wright thermal cutout an electrically heated contact post is mounted within an enclosing casing of insulating material together with a cooperating flexible contact which is biased out of engagement with the electrically heated post. A fusible link is provided to interconnect the electrically heatedcontact post and the flexible contact. With this arrangement the thermal capacity of the electrically heated post provides a desirable time delay in the fusing of the link upon occurrence of overload conditions inthe circuit controlled by the cutout. Hence, this form of thermal cutout is particularly advantageous in protecting small motors, such as used on washing machines or other similar devices against injurious overheating or burnout due to stalling, or the like, without however responding to the temporary excessive inrush of current ordinarily occurring when such motors are started. I

The fusible link of the Wright thermal cutout is made of two parts, one of the parts being yoke shaped to encircle the electrically heated contact post and the other part being a bar secured across the ends of the yoke by readily fusible solder. In practice difiiculty may be experienced upon fusing of the solder due to the separated parts of the link falling into contact with the energized parts of the cutout thus preventin ing of the circuit and thereby do; intended purpose of the cutout.

The principal object of the present inventionis to overcome this difiiculty by rovidmg means for holding at least the yo *e part of the fusible link on the electrically heated post after the link is fused.

In the accompanying drawing, Fig. 1 is a sectional view) of the thermal cutout provided with my improved form of fusible link and Fig. 2 is a top view of the cutout. I In Fig. 1 the contact post 10 is mounted within the insulating enclosing c havin the removable top 12. A heater 13' 'encirc 'ng the post 10 serves to heat the post the openeating the 1980. Serial No. 445,492.

with a time delay action upon the occurrence of overloads in the circuit protected by the cutout.

The flexible contact 14 is mounted at the bottom of the enclosing casing 11 so as to be terminal 18 through the heater 13 to the past 10 and then through the fusible link 15 and the spring contact 14 to the terminal 19'.

In order to insure that the yoke 16 is held on the post 10 after the bar 17 is released by the melting of the fusible solder, the small held against projections 20 are punched out from the opposits sides of the yoke 16 so as to extend partially around the post 10 when the link 15 is in its operative position. In the yoke 16, which is the part most likely to fall so as to accidentally reestablish the circuit through the cutout after the fusible solder has melted, is maintained in its nor mal operating osition.

After the li 15 is fused b current, the separated parts ot the link may be readily removed and a new link inserted in the ,cutout upon removing the cover 12.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In an electric cutout, an electrically this way engagement with the post, and a two-part fusible link encircling the contact and the post for interconnecting the same and provided with means for holding .at least one artdthereof on the post after the link is use 2. In an electric cutout, an electrically heated contact post, a flexible out of engagement with the post, and a removable an overload heated contact post, a contact biased out of contact biased two-part link having is, til-shaped 2' momso yoke part for encircling the post, aid a bar member secured against the ends of the yoke by readily fusible solder for holdin the flexible contact against its bias, said o homing 5 projections unched out from t e opposito sides thereo for holding the yoke on tho post after the solder is fused.

In witness whereof, I have herounio set my hard this 16th day of April, 1930.

lo ADONIRAM J. GREEN.