Manual reset electrical equipment protector apparatus

• US 5,854,585 A
• Filed: 02/20/1998
• Issued: 12/29/1998
• Est. Priority Date: 04/10/1997
• Status: Expired due to Fees

• Current Assignee: Sensata Technologies Massachusetts Incorporated (Sensata Technologies Holding Plc)
• Original Assignee: Texas Instruments, Inc.
• Inventors: Kingma, Geoffrey
• Primary Examiner(s): Feild, Lynn D.
• Assistant Examiner(s): Vortman, Anatoly
• Application Number:
  US09/027,174
• Time in Patent Office: 312 Days
• Field of Search: 337/348, 337/343, 337/342, 337/333, 337/334, 337/298, 337/312, 337/314, 337/362, 337/365, 337/367, 337/372, 337/380
• US Class Current: 337/367
• CPC Class Codes: H01H 37/5409 Bistable switches; Resetting means
• CPC Class Codes: H01H 37/5418 using cantilevered bimetallic snap elements

Abstract

A manual reset electrical protector (10, 10'"'"') has a reset assembly (26, 26'"'"') having a guideway (28a, 28a'"'"') and track (28c, 28c'"'"') in which a slide member (30, 34, 34'"'"') is movable between a protracted position interrupting the movement of a movable electrical contact (22) mounted on a thermostatic disc (20) to preventg engagement of the movable contact with a stationary electrical contact (24) and a retracted position in which the movable contact is allowed to move unfettered into the contacts engagement position. A push button (32, 32'"'"') has a cam member (32a, 32a'"'"') which, when the push button is depressed, rides against a follower (30b, 34b) attached to the slide member, causing the slide member to move to the retracted position against the bias of a spring (30d, 36). The movable contact (22) prevents movement of the slide member to the blocking, protracted position when in the contacts engaged position.

Claims

1. A manual reset circuit protector comprising:

a first housing member defining a switch cavity and having a wall mounting thereon a stationary electrical contact, the wall having a reset housing aperture formed therethrough,

a second housing member attached to the first housing member, the second housing member mounting thereon a movable contact assembly, the movable contact assembly comprising a snap acting, cantilever mounted thermostatic disc, the disc having a free distal end, a movable electrical contact mounted on the free distal end adapted to move into and out of engagement with the stationary electrical contact,

respective electrical terminals electrically connected to the stationary and movable electrical contacts,

a manual reset assembly comprising a third housing member attached to the wall of the first housing member in alignment with the reset housing aperture, the third housing member having an opening formed therethrough in communication with the reset housing aperture, a slide member mounted on the third housing member within the switch cavity for rectilinear movement toward and away from the stationary electrical contact, the slide member having a follower surface extending into the opening in the third housing member, a push button disposed in the opening in the third housing member and movable in a direction in and out of the opening, the push button having a cam surface receivable on the follower surface and spring means for biasing the slide member toward the stationary electrical contact, the slide member being movable between a first retracted position away from the movable stationary contact when the push button is depressed into the opening by means of the cam member co-acting with the follower surface to push the slide member against the bias of the spring and a second protracted position adjacent the stationary electrical contact and in alignment with the movable electrical contact when the snap acting disc can snap to an open contact position allowing the slide to move in response to the bias of the spring, the slide member when in the protracted position limiting movement of the movable electrical contact when the disc attempts to snap back to the contacts engage position.

2. A manual reset circuit protector according to claim 1 in which the movable contact assembly includes a heater element.

3. A manual reset circuit protector comprising:

a first cup shaped electrically conductive housing member defining a switch cavity having an end wall and having a reset housing receiving aperture formed through the end wall,

a stationary electrical contact mounted on the end wall,

a second electrically conductive housing member generally configured as a lid attached to and electrically isolated from the first housing member,

an electrically conductive, snap acting disc cantilever mounted in the switch cavity and electrically connected to the second housing member, a movable electrical contact mounted on a free distal end of the disc movable into and out of electrical engagement with the stationary electrical contact,

a third generally annular housing member having a bore attached to the first housing member with the bore in alignment with the reset housing receiving aperture, the third housing member having a guideway received in the switch cavity, a slide member mounted in the guideway for rectilinear movement between a protracted position adjacent the stationary electrical contact and a retracted position away from the stationary electrical contact, a push button disposed in the bore of the third housing member and being movable toward and away from the switch cavity, the push button having a camming surface depending therefrom, the slide member having a follower surface projecting upwardly therefrom adapted to engage the cam member and a spring member urging the slide member toward the protracted position, the slide member when in the protracted position blocking movement of the movable electrical contact as the movable electrical contact moves from a contacts disengaged position toward contact engagement.

4. A manual reset circuit protector according to claim 3 further comprising a heater mounted on the second housing member and the snap acting disc in turn mounted on the heater.

5. A manual reset circuit protector according to claim 3 in which the spring member is generally U-shaped having first and second legs joined together at a bight, one leg reacting against the third housing member in the bore thereof and the other leg being operatively connected to the slide member.

6. A manual reset circuit protector according to claim 3 in which the slide member is generally aligned with the snap acting disc.

7. A manual reset circuit protector according to claim 3 in which the stationary contact has a sidewall portion and an extension of the rectilinear movement of the slide member intersects the sidewall portion of the stationary contact whereby engagement of the slide member with mating surfaces of the contacts is precluded.

8. A manual reset circuit protector according to claim 3 in which the spring member is generally W-shaped having a first and second legs fixedly attached to the slide member and having a third leg reacting against the third housing member, the first leg forming the follower surface.

9. A manual reset circuit protector according to claim 3 in which the push button is formed with a sleeve having a free distal end, a lip extends radially outwardly from the distal free end, the bore of the third housing member formed with a lip which interacts with the lip of the push button sleeve to limit outward movement of the push button.

10. A manual reset circuit protector according to claim 9 in which the lip of the push button has a tapered surface portion which allows one directional movement of the push button lip passed the lip of the third housing member so that the push button can be inserted into the bore of the third housing member.