US3833784A

US3833784A - Safety slide switch

Info

Publication number: US3833784A
Application number: US00319920A
Authority: US
Inventors: D Bobel; R Lotter
Original assignee: Skil Corp
Current assignee: Skil Corp
Priority date: 1972-12-29
Filing date: 1972-12-29
Publication date: 1974-09-03
Anticipated expiration: 1991-09-03

Abstract

The actuator of the slide switch is associated with contact means for opening and closing the same when the actuator is moved back and forth along a first path. The actuator includes an abutment surface arranged for abutting engagement with a fixed abutment surface, the latter being contained in a plane perpendicular to the first path. The actuator is mounted by support means including yieldable means permitting movement of the actuator back and forth along a path contained in said plane thereby to disengage the abutment surfaces for thereafter permitting movement of the actuator along the first path.

Description

United States Patent Bobel et al. 1 Sept. 3, 1974 [541 SAFETY SLIDE SWITCH 3,398,250 8/l968 Bowers 200 157 3,555,213 l/l97l Cherr et al. ZOO/166 BH X [75] Inventors: Davd Bob, Buffalo 9 3,564,186 2/1971 Mittefistadt et al zoo/153.24 ux Robe" Lott", Mundelem, both 3,575,560 4 1971 Mayer et al 200 157 x of 111. 3,784,765 9/1972 Daly 200 157 x [73] Assignee: Skil Corporation, Chicago, Ill.

Primary Examiner-Robert K. Schaefer [22] Flledl 29, 1972 Assistant ExaminerWilliam J. Smith 211 App] 319,920 Attorney, Agent, or FirmMcDougall, Hersh & Scott [52] US. Cl 200/157, ZOO/324, 200/327, ABSTRACT zoo/330 The actuator of the slide switch is associated with [51] Int. Cl. H01h 3/20, H01h 9/06 Contact means f Opening and closing the Same When [58] Field of Search ZOO/157, 172 A, 169 R, the actuator is moved back and forth along a first ZOO/169 16 166 6135 path. The actuator includes an abutment surface ar- 16 16 16 60 ranged for abutting engagement with a fixed abutment surface, the latter being contained in a plane perpen- [56] References Cted dicular to the first path. The actuator is mounted by UNITED STATES PATENTS support means including yieldable means permitting 2,519,294 8/1950 Schneider ZOO/60 x movement of the actuator back and forth along a P 2,562,687 7/1951 Anderson 200/60 X contained in said plane thereby to disengage the abut- 2,564,612 8/1951 Schneiden. 200/60 ment surfaces for thereafter permitting movement of 2,676,217 4/1954 Garbs ZOO/60 the actuator along the first path 3,124,306 3/1964 Schotz ZOO/6O X 3,297,840 1 1967 Gray et al. ZOO/60 3 Claims, 3 Drawing Figures SAFETY SLIDE SWITCH BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates generally to electric switches. More particularly, the present invention relates to manually-operated slide switches, i.e., switches wherein the actuator is mounted for being slid back and forth between on and off positions thereby to control the associated electric contacts. Specifically, the invention relates to safety means for minimizing the possibility of inadvertent movement of the actuator to the on position.

2. The Prior Art Slide switches of the general type referred to hereinabove are well known in the art. Some of these slide switches are provided with detent means for yieldably or releasably holding the actuator in both its on and off positions. However, such detent means permit ready movement of the actuator when the same is pushed toward either the on or off position.

Slide switches of the type under consideration are provided for use in a wide variety of electrical devices, including portable electric tools and appliances. In certain of these tools and appliances, such as portable electric saws, hedge trimmers and shears, for example, injury to the operator can very likely result if the tool motor is inadvertently energized. With the use of these prior art slide switches, inadvertent energization is possible because of the ease in which the actuator may be slid to the on position. With the use of these switches in such tools and appliances, the operator may move the actuator to the on position in a precipitous manner and without fully considering whether the area adjacent the tool cutting members is clear of the operators person or the electrical cord extending to such tool. Further, such actuators may be inadvertently moved to the on position as the result of being engaged by the operators clothing or other objects in the vicinity of the tool.

The prior art slide switches of which we are aware do not provide simple and reliable means for preventing the ready movement of the actuator to the on position. The present invention provides an improved safety feature for such slide switches and includes means preventing movement of the slide switch actuator to the on position without first imparting a predetermined movement to the actuator for releasing the same for movement thereafter to the on position.

SUMMARY AND OBJECTS OF THE INVENTION A primary object of the present invention is the provision of a new and improved safety slide switch.

Another object of the present invention is the provision of a slide switch, wherein releasable means are provided to prevent movement of the actuator to the on position prior to disengagement of the releasable means.

Still another object of the present invention is the provision of a safety slide switch including an actuator associated with contact means for opening and closing the same when the actuator is moved back and forth along a first path, an abutment surface on the actuator arranged for abutting engagement with a fixed abutment surface thereby to prevent movement of the actuator along its first path, and support means for the actuator including yieldable means permitting movement of the actuator back and forth along a second path thereby to disengage the abutment surfaces for thereafter permitting movement of the actuator along the first path.

These and other objects and advantages of the present invention will become apparent from the following specification disclosing a preferred embodiment shown in the accompanying drawings.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view showing the safety slide switch of the present invention in its off position and mounted within the housing of a portable electric tool or appliance, the housing of the latter being fragmentarily shown;

FIG. 2 is a sectional view similar to FIG. 1 and showing the switch in its on position; and

FIG. 3 is a top plan view of the switch in the on position.

DESCRIPTION OF A PREFERRED EMBODIMENT The safety slide switch of the present invention has particular, although not exclusive, application for use in a portable electric tool or appliance of the type wherein inadvertent energization of the tool motor presents a potentially hazardous condition. Such tools are exemplified by portable electric saws, hedge trimmers and shears. The housing of such a tool is fragmentarily illustrated and designated 10, the housing having a handle portion 10a adapted to be gripped by the hand of the operator of the tool. The handle portion 10a includes a generally rectangular opening 11 having oppositely disposed

edges

11a, 11b constituting fixed abutment surfaces. The other oppositely disposed edges 11c, 11d of the opening constitute guide surfaces for the actuator of the safety switch as will be explained hereinbelow.

The safety switch of the present invention, generally designated 12, includes a housing or casing 14 having a pair of terminals 15 depending therefrom. The switch includes an operating member 16 for reciprocal sliding movement in the direction of the arrows shown in FIGS. 1 and 2. This operating member is associated with movable contact means contained within the casing 14 so as to close a circuit when the operating member 16 is moved to the right, i.e., to the on p0sition,'and to open the circuit when the operating member is moved to the left, i.e., to the off position. The switch 12 is secured within the housing portion 10a by any suitable form of engagement between the casing 14 and a pair of

ribs

18, 19, the latter being integral with the housing 10.

The switch 12 further includes a generally rectangular shaped plate 20 which serves, among other things, as a cover for the casing 14. The plate 20 includes a suitable rectangular opening (not shown) to accommodate movement of the operating member 16.

The switch 12 includes a thumb or finger operable actuator 22, a portion of which extends through the opening 11. This actuator includes a first cavity 23, generally in the form of a parallelepiped, and opening at the bottom of the actuator. A second cavity 24'is formed in the actuator centrally thereof, which cavity is generally rectangular in cross section and communicates at its bottom with the cavity 23. The cavity 24 slidably receives the operating member 16; that is to say, the actuator 22 is slidably mounted on the operating member 16 and within the opening 11 for up and down reciprocal movement back and forth between the two positions shown in FIGS. 1 and 2.

A leaf spring 26 is contained within the cavity 23, this spring having a bight portion 26a which engages wall portions of the cavity 23. The spring 26 has distal end portions 26b slidably engaged with the upper surface of the plate 20.

The actuator 22 has a bottom wall surface 28 arranged to engage the upper surface of the plate 20 so as to limit downward movement of the actuator 22 against the bias of the spring 26; this bottom surface will also slide along the plate 20 to permit movement of the actuator back and forth between its on and off positions as will be explained below.

The actuator includes a notch defining an abutment surface 30 and a ledge surface 31. The actuator is further defined by a pair of stepped

ledge surfaces

32, 33, these surfaces being adapted to engage respective wall surfaces 34, 35 formed on the interior of the housing portion a adjacent the opening 11. Finally, the thumb-engageable portion of the actuator includes side walls 36, 37.

The safety slide switch of the present invention is shown in its off position in FIG. 1. In this position, the

spring 26 urges the actuator 22 upwardly or outwardly of the tool housing with the

ledge surfaces

31, 33 in respective engagement with the ledge surfaces 34, 35. The surface 30 on the actuator is in abutting engagement with the edge surface 11a on the housing thereby to prevent movement of the actuator to the right, i.e., to its on position. In the off position, the actuator 22 may not be moved to the left due to the abutting engagement of the edge surface 11b with the side wall 37 of the actuator. Accordingly, it is seen that when the safety slide switch is in its off position, the actuator 22 cannot be merely slid to its on position.

When it is desired to energize the tool or appliance which includes the safety slide switch of this invention, the actuator 22 must first be depressed against the bias of the spring 26. This will result in disengagement of the

surfaces

30 and 11a on the actuator and housing portion 10a, respectively. After this inward or downward movement of the actuator 22 has been completed, the actuator may then be slid to the right, i.e., to the on position. Movement of the actuator in this direction is limited by engagement of the actuator side wall 36 with the fixed abutment surface 1 1a. The actuator 22 may be released by the operator with the former in the on position; the spring 26 will urge the actuator 22 upwardly or outwardly with the ledge surface 32 in engagement with the wall surface 34 of the housing portion 10a. It will be apparent that when it is desired to de-energize the tool motor, the actuator 22 is slid to the left whereupon the spring 26 will act to snap the actuator 22 upwardly or outwardly whereupon the same will be captured between the edge surfaces 11a, 1 lb as illustrated in FIG. 1.

Thus, the present invention provides a safety slide switch having an actuator which is unlikely to be moved to the on position through inadvertence. Should the actuator 22 be engaged by the operators clothing or objects adjacent the tool, it is unlikely that the actuator will he slid to the on position since it must be forced inwardly of the tool housing before such sliding movement is possible. The construction of the actuator of the safety slide switch reduces the possibility of the operator himself energizing the tool motor in a precipitous manner and before he is ready to perform a particular operation, since the operator must first move the actuator inwardly of the tool before the actuator can be moved to the on position. This additional movement or motion which the operator must perform will occupy a short time period giving the operator a moment to reflect on whether or not the tool or appliance is ready for safe operation.

We claim:

I. In a slide switch of the type adapted for mounting in a portable tool or the like having a housing wall with an opening therein, the periphery of which opening defines a plane, the improvement comprising:

a. switch means in said housing including a movable operating member connected with contact means for opening and closing the same when said operating member is moved, respectively, back and forth along a first path contained in said plane;

b. an actuator having a portion thereof extending through said opening and also having a cavity with the walls thereof slidably receiving the walls of a portion of said operating member, said walls being contained in respective planes disposed substantially perpendicular to said first mentioned plane and thus the sliding interengagement between said walls serving to mount said actuator for reciprocal movement relative to said operating member and back and forth along a second path which intersects said plane substantially perpendicular thereto;

c. first and second stop means alternately engaged by said actuator thereby to limit movement of the same along said second path;

d. biasing means engaged with said actuator and acting to urge said portion thereof outwardly through said opening;

e. a first abutment surface on said actuator for movement therewith;

f. a fixed formation adjacent said actuator;

g. a second abutment surface on said fixed formation;

and

h. said first and second abutment surfaces being contained in respective planes substantially perpendicular to said plane and normally being in abutting engagement with each other thereby to prevent said forth movement of said actuator along said first path, said first and second abutment surfaces being disengaged only by movement of said actuator along said second path in a direction inwardly of said opening, the disengagement of said first and second abutment surfaces thereafter permitting movement of said actuator in said forth direction for closing said contact means.

2. The improvement according to claim 1 wherein said fixed formation is defined by a portion of said housing wall adjacent said opening.

3. The improvement according to claim 2 further defined by: p

a. said first stop means being defined by inner surfaces of said housing wall adjacent said opening; b. said second stop means being defined by a plate contained in a plane parallel with said first mentioned plane; and I c. said actuator having a planar wall surface arranged to engage said plate thereby to limit movement of the actuator inwardly of said opening, the sliding engagement between said plate and said planar wall surface serving to guide said actuator during its movement along said first path.

Claims

1. In a slide switch of the type adapted for mounting in a portable tool or the like having a housing wall with an opening therein, the periphery of which opening defines a plane, the improvement comprising: a. switch means in said housing including a movable operating member connected with contact means for opening and closing the same when said operating member is moved, respectively, back and forth along a first path contained in said plane; b. an actuator having a portion thereof extending through said opening and also having a cavity with the walls thereof slidably receiving the walls of a portion of said operating member, said walls being contained in respective planes disposed substantially perpendicular to said first mentioned plane and thus the sliding interengagement between said walls serving to mount said actuator for reciprocal movement relative to said operating member and back and forth along a second path which intersects said plane substantially perpendicular thereto; c. first and second stop means alternately engaged by said actuator thereby to limit movement of the same along said second path; d. biasing means engaged with said actuator and acting to urge said portion thereof outwardly through said opening; e. a first abutment surface on said actuator for movement therewith; f. a fixed formation adjacent said actuator; g. a second abutment surface on said fixed formation; and h. said first and second abutment surfaces being contained in respective planes substantially perpendicular to said plane and normally being in abutting engagement with each other thereby to prevent said forth movement of said actuator along said first path, said first and second abutment surfaces being disengaged only by movement of said actuator along said second path in a direction inwardly of said opening, the disengagement of said first and second abutment surfaces thereafter permitting movement of said actuator in said forth direction for closing said contact means.

3. The improvement according to claim 2 further defined by: a. said first stop means being defined by inner surfaces of said housing wall adjacent said opening; b. said second stop means being defined by a plate contained in a plane parallel with said first mentioned plane; and c. said actuator having a planar wall surface arranged to engage said plate thereby to limit movement of the actuator inwardly of said opening, the sliding engagement between said plate and said planar wall surface serving to guide said actuator during its movement along said first path.