US3405243A

US3405243A - Actuating lever for a switch

Info

Publication number: US3405243A
Application number: US618241A
Authority: US
Inventors: Walter L Cherry; Robert T Main
Original assignee: Cherry Electrical Products Corp
Current assignee: Cherry Corp
Priority date: 1967-01-12
Filing date: 1967-01-12
Publication date: 1968-10-08
Anticipated expiration: 1985-10-08
Also published as: GB1185500A; DE1615937A1; FR1550767A; DE1615937B2

Description

Oct 8, 1968 w. L. CHERRY ET AL 3,405,243

ACTUATING LEVER FOR A SWITCH HHHHIII Filed Jan. 12, 19s? )QVTORS y Mama. Lz A RT m E Z M Ma WE United States Patent 3,405,243 ACTUATING LEVER FOR A SWITCH Walter L. Cherry and Robert T. Main, Highland Park, Ill., assignors to Cherry Electrical Products Corporation, Highland Park, Ill., a corporation of Illinois Filed Jan. 12, 1967, Ser. No. 618,241 Claims. (Cl. 200-67) ABSTRACT OF THE DISCLOSURE Field of invention A snap-action switch having a housing of non-conductive material which provides a cavity for housing an overcentering mechanism. The over-centering mechanism includes a fixed terminal providing pivot posts to which is pivotally connected a substantially flat switch blade, an elongated actuating lever has one end pivotally inserted in a seat provided by one wall of the housing and its opposite end connected by a coil spring to the switch blade. The actuating lever is of a length greater than the switch blade and in order to accommodate the pivotal movementof the free end of the switch blade the lever has its medial portion offset laterally out of its normal longitudinal plane. The lateral offset permits the actuating lever to be pivoted by a relatively light operating force by reason of the distance between its pivotal seat and its movable distal end.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

This ivention will be best understood by reference to the accompanying drawings showing the preferred form of construction, and in which:

FIG. 1 is a side elevational view of the improved snapaction switch with the cover removed;

FIG. 2 is a side elevational view of the side cover;

FIG. 3 is a side elevational view of our improved snapaction switch similar to FIG. 1, but showing the parts thereof in an actuated position;

FIG. 4 is a perspective view of the internal parts of the improved snap-action switch in a semi-exploded relation; and

FIG. 5 is a fragmentary detailed sectional view of one end of the switch housing.

Referring to FIG. 1, it is noted that the improved snapaction switch includes a case comprising two side sections and 11. Each of these

side sections

10 and 11 are hollowed out to provide an

internal cavity

12 and 13, respectively, adapted to confront each other when the sections are mounted together to form a complete casing.

The switching mechanism includes a pair of spaced apart fixed contact-bearing

terminals

14 and 15, positionable in

slots

17 and 18 formed in the end wall 16 of the side 10, with the terminals being of a width equal to the depth of such slots so that when the side sections 10' and "ice 11 are mounted together, the terminals 14 and will be held in a fixed position relative to the switch casing.

A terminal pivot post 19 extends out of the bottom wall 20 of the casing 10 and it, too. is adapted to sit in a slot 21 formed in such bottom wall so that it is held in a fixed position within the casing when the

sections

10 and 11 are assembled in mating relationship.

The end of the terminal post 19 which is positioned within the casing, is bifurcated to provide spaced apart

pivot posts

22 and 23. It should be noted that the opposite corresponding edges of each of the

posts

22 and 23 are notched out so as to provide a pivot seat for respective matching ends of the arms 24 and 25 of the switch blade 26. The free ends of the arms 24 and 25 of the switch blade 26 are provided with oppositely facing

shoulders

27 and 28 which, when the blade 26 is mounted to the pivot post 19, extend on opposite sides of the notched pivot seats formed in the

posts

22 and 23 of the terminal post 19.

The switch blade 26 has formed therein a slot 29 which extends from one longitudinal edge of the blade 26 in the direction of, and terminates at the longitudinal midline of the switch blade 26. By this slot 29 a cantilevered type blade is formed having a resilient end 30 which carries thereon a contact 31 movable between

fixed contacts

32 and 33 carried by the fixed contact-bearing

terminals

14 and 15. It should be noted that the

contacts

32 and 33 are adapted to be in vertical alignment and off-center with respect to the longitudinal axis of each of their respective terminals 14 and 15-this for a purpose hereinafter made apparent.

An actuator level 34 formed from a substantially flat elongated member provides a base 35 pivotally seated in a horizontally extending V groove v36 formed in the interior face 37 of the end wall 16 of the side section 10. The medial portion of the elongated actuator lever 34 is provided with a lateral offset 38 adapted to extend in close spaced parallel relation to the rear wall 39 of the section 10.

The remaining section 40 of the actuator lever 34 is of a width slightly less than and extends through the space between the

posts

22 and 23 of the terminal pivot post 19, as

such posts

22 and 23 are positioned within the cavity 12 of the side section 10.

The opposite free end of the actuator lever 34 is bent at right angles relative to the general longitudinal length of such lever and forms a vertically extending head 41. The top edge of the head 41 is notched as at 42 and is provided with an aperture 43 both of which cooperate to receive a hooked end 44 of a coil spring 45. The spring 45 extends through the

pivot posts

22 and 23 of the terminal pivot post 19 as well as between the

arms

27 and 28 of the switch blade 26 and has its opposite end 46 attached to the blade 26 through the slot 29 formed therein.

As shown in FIG. 1, the spring 45 as it extends between the switch blade 26 and the actuator lever 34, urges the blade 26 in one direction toward its connection to the terminal pivot post 19 and simultaneously urges the actuating lever 34 in an opposite direction so that the base 35 thereof is pivotally seated in the V-shaped groove 36 provided by the side section 10 of the casing. By this arrangement the switch blade 26 is pivotally connected to the terminal post 19 while the actuator lever 34 is pivotally connected relative to the end wall 16 of the side section 10 of the switch casing.

A switch actuating button 47 is adapted to be slidably 3 contained within the

cavities

12 and 13 provided by the

side Sections

10 and 11 of the switch casing. The switch actuating button 47 provides an exterior dome 48 as well as an interior bearing member 49. The interior bearing member 49 is adapted to engage the edge of the enlarged head 41 of the actuating lever 34, as shown in FIGS. 1 and 2. As an external force is applied to the dome 48 of the switch actuating button 47, it will move in a guided vertical path as seen in FIGS. 1 and 2, causing a corresponding pivotal movement of the actuating lever 34 about its pivotal connection to the end wall 16 of the side section 10. This pivotal movement of the actuating lever 34 carries with it a corresponding movement of the hooked end 44 of the coil spring 45. As the coil spring 45 is moved into a lower plane, it passes through the over-centering line of the switch blade 26, causing the same to move with a snap action between the fixed. contact-bearing

terminals

14 and 15, into the position shown in FIG. 3. Upon removal of the external force to the actuating buttom 47, the parts of the snap-action mecha-.

nism just identified will return to their original positions Shown in FIG. 1, due to the tension created on the coil spring 45 and the positioning of the actuating lever 34 and the switch blade 26.

By directing the actuating force onto the edge of the head 42 of the actuating lever 34 at a point farthest removed from its pivotal connection with the wall 16, only a relatively light actuating force is necessary to effect the positive snap-action movement of the components of the switching mechanism to effect the switching operation thereof. By the specific arrangement of the components as hereinbefore described, an operating force of less than fourteen ounces (14 oz.) is sufficient to effect switching actuation of the snap-action switch.

The positive pivot points of both the switch blade 26 relative to the fixed terminal pivot post 19, and the actuating lever 34 relative to the V groove 36, permit a simple assembly of the switching components and reduce the acceptable error and tolerance of these parts relative to each other which is essential not only for the effective operation of the switch but also in the reduction of the operating force required to actuate the same.

The arrangement of parts accomplishes the stated objects of this invention Without affecting the general geometrics of the components and without reduction of the current-carrying capacity of the switch blade 26. The switch blade 26 can maintain its full current-carrying capacity by reason of its size, which need not be reduced because of the fact that the actuating lever 34 is provided with the offset portion 38 which normally lies on one side of and out of the path of movement of the switch blade 26 as it is caused to move between the fixed

contactbearing terminals

14 and 15. This relationship of the blade 26 and lever 34 is as a result of having, as shown in FIGS. 1 and 3, their respective points of pivotal connection with the

pivot posts

22 and 23 and the end wall 16 of the housing, respectively, in substantial horizontal alignment. Any increase in tension of the spring 45 developed by the movement of the actuating lever 34, is transmitted to the switch blade 26 as well as the pivotal connection of the actuating lever 34 and the end wall of the side section 10 of the casing, and is not imparted into a line of resistance against the movement of the switch-actuating button 47, thus removing the necessity of a greater amount of operating force to actuate the switch components.

While we have illustrated and described the prefeged form of construction for carrying our invention into effect, this is capable of variation and modification without departing from the spirit of the invention. We therefore do not wish to be limited to the precise details of construction set forth, but desire to avail ourselves of such variations and modifications as come within the scope of the appended claims.

Having thus described our invention, what we claim as new and desire to protect by Letters Patent is:

1. An actuator lever for a snap action switch including a housing provided with a center cavity, an overcentering mechanism within the cavity consisting of a fixed terminal having spaced apart parallel pivot posts to which a movable switch blade is pivotally connected by a coil spring extending between the pivot posts and connected at one end to the switch blade and with its opposite end connected to the actuating lever with the free end of the blade carrying a contact movable between spaced terminal members wherein the improvement comprises:

(a) an elongated substantially flat actuating lever pivotally positioned within the cavity of the housing and having a length greater than that of the switch blade,

(b) means pivotally connected one end of the lever to one wall of the housing between and in vertical alignment with the spaced terminal members longitudinally beyond the free end of the switch blade,

(c) means provided by the opposite end of said lever positioned between the pivot posts of the fixed terminal and beyond the corresponding opposite end of the switch blade for connecting the opposite end of the spring thereto in the plane of a midline through the long axis of the blade and the pivotal connecting means between said one end of the lever and the housing,

(d) said lever having a medial portion offset laterally out of its normal longitudinal plane and to one side of the vertically aligned spaced terminals to provide clearance for the contact carried by the free end of the blade as the same is pivoted in one direction between the spaced terminal members by the pivotal movement of said opposite end of said actuating lever and the overcentering mechanism.

2. An actuating lever for a snap action switch as defined by claim 1 wherein said means pivotally connecting one end of the lever to the housing comprises a V-shaped groove formed in one end wall of the housing between the spaced terminal members and in horizontal alignment with the point of pivotal connection between the switch blade and the pivot posts of the fixed terminal.

3. An actuating lever for a snap action switch as defined by claim 1 wherein said means provided by the opposite end of said lever comprises a head portion formed at right angles to the longitudinal length of the lever beyond the corresponding opposite end of the switch blade to which the opposite end of the spring is connected so that it lies in a horizontal plane between the pivot posts of the fixed terminal and is movable with said opposite end of said lever to move the contact carrying end of the switch blade with a snap action through the offset portion of the lever and between the spaced terminal members.

4. An actuator lever for a snap action switch including a housing provided with a center cavity, an overcentermechanism within the cavity consisting of a fixed terminal having spaced apart parallel pivot posts to which a movable switch blade is pivotally connected by a coil spring extending between the pivot posts and connected at one end to the switch blade and with its opposite end connected to the actuating lever with the free end of the blade carrying a contact movable between spaced terminal members wherein the improvement comprises:

(a) an elongated substantially flat actuating lever of a length greater than the switch blade,

(b) means on one end of said lever extending transversely to its length and positioned to one side of the pivot posts of the fixed terminal and beyond the corresponding opposite end of the switch blade for connecting the opposite end of the spring thereto,

(c) said lever having at its opposite end a base portion of the width greater than that of the lever and extending transversely to its longitudinal length and pivotally connected to one wall of the housing between the spaced terminal members and in horizontal alignment with the point of pivotal connection between the switch blade and the pivot posts of the fixed terminal,

(d) said lever having a medial portion ofiset laterally with respect to said first mentioned means and said base portion providing clearance for the contact carried by the free end of the switch blade as the same is pivoted in one direction by the overcentering mechanism.

5. An actuator lever for a snap action switch as defined by claim 4 including means pivotally connecting said base portion of the said lever to one wall of the housing, which means comprises a V-shaped groove formed in the one wall of the housing between the spaced terminal pivotal connection between the switch blade and the pivot posts of the fixed terminal.

References Cited UNITED STATES PATENTS ROBERT K. SCHAEFER, Primary Examiner.

members and in horizontal alignment with the point of 15 SMITH, Assistant Examiner-