Claims:
1. An electric switch including in combination,
2. The switch according to claim 1 wherein said cover means with an open
3. The switch according to claim 2 wherein said coverplate having slots
4. The switch according to claim 1 wherein said body portion of said pushbutton actuator includes a projection thereon, said projection engageable with one of said laterally displaceable members upon the longitudinal displacement of said pushbutton actuator to produce a camming
5. The switch according to claim 4 wherein said laterally displaceable member includes a wedge shaped block having dimensional stability, said wedge surfaces engageable with one of said projections on said body
6. The switch according to claim 1 wherein said extension arm is centrally
7. The switch according to claim 1 wherein said resilient means is a metal
8. In an electric switch comprising a housing, a plurality of fixed contacts mounted within said housing, a plurality of pushbutton actuators each having a button portion extending outwardly from said housing and having an actuator body portion having resiliently mounted contacts for selectively cooperating with said fixed contacts for completing an electric circuit, and a plurality of laterally displaceable members slidably positioned within said housing to be selectively engageable by one of said actuator body portions, the combination including cover means secured to the housing and having open spaces therein, an extension arm secured to each of said displaceable members on one side face thereof, each of said extension arms extending outwardly through one of said spaces in the switch cover means, and resilient means secured to said extension arm of one of said displaceable members and to said cover means, said resilient means returning said displaceable member to its undisplaced position when said displaceable member is laterally displaced by
9. The switch according to claim 8 wherein said cover means secured to said housing and having open spaces therein includes a coverplate having slots
10. The switch according to claim 9 wherein said coverplate having slots therein fruther includes notches on the edge thereof and resilient means secured to said extension arm and to a selected notch on said coverplate.
11. The switch according to claim 9 wherein said extension arm secured to each of said displaceable members extends outwardly through one of said slots in said coverplate.
Description:
BACKGROUND OF THE INVENTION
Pushbutton switch assemblies utilizing sliding block-type switch actions have been developed for use where it is desirable to provide selective control over a number of operations, or selective control over a continuous sequence of opprations. This type switch assembly is particularly desirable where it is necessary to provide smooth operating devices which are simplified in structure while possessing functional flexibility and versatility. However, because of the restrictive space in which such switch assemblies are frequently mounted, previous attempts to develop switches, and in particular, momentary pushbutton switches have not been successful because the resultant momentary switches have been bulky, too expensive and lacking in the feature of having the facility for converting selected pushbutton switch positions to momentary pushbutton switch positions.
SUMMARY OF THE INVENTION
One object of this invention is to provide an improved pushbutton switch assembly having momentary pushbutton switch positions.
It is a further object of this invention to provide a multi-station switch assembly wherein at least one of the switch actuating pushbuttons is mounted for engagement with a spring biased laterally displaceable member so as to facilitate initial engagement and momentary release for return to the nonactuating position.
A further object of this invention is to provide an improved multi-station pushbutton switch having two momentary pushbutton switch positions.
Still another object of this invention is to provide a momentary pushbutton switch utilizing sliding block-type action, wherein one or more of the pushbuttons may be selectively engageable with spring biased displaceable members to provide momentary return of the depressed pushbutton.
In one embodiment of this invention, a plurality of block-like longitudinally displaceable pushbutton switch actuators are slidably mounted in a switch housing having a coverplate with notches and slots therein and having a plurality of fixed contacts mounted within said housing. The pushbutton actuators have a button portion extending outwardly from the housing and an actuator body portion with resiliently mounted contacts for selectively cooperating with the corresponding fixed contacts mounted in the housing. The actuator body portion has a projection at its end, with the surfaces of the projection acting as cam surfaces when the pushbutton is depressed. A plurality of laterally wedge shaped displaceable members are slidably positioned within the switch housing such that one of the wedge surfaces of the member is selectively engaged by one of the actuator body portion projections. Molded integral to the face of each of the members and extending outwardly through the slots in the coverplate is an extending arm to which is attached one end of a resilient means which is further anchored to a selected notch in the switch housing coverplate. Thus, when a pushbutton is depressed, the member selectively engaged by the actuator body portion is laterally displaced thereby moving all of the displaceable members in that direction. The lateral movement of the member creates a tension on the spring such that when the pressure on the actuator is released, the displaceable member momentarily returns to its original position and thereby returns the actuator to its initial nonactuating position.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a multiple pushbutton switch assembly utilizing the spring biased displaceable member in accordance with the invention with the top plate partially removed;
FIG. 2 is a side elevation view in cross-section showing a single pushbutton switch assembly of the instant invention;
FIG. 3 is an expanded side elevation view showing the laterally displaceable member;
FIG. 4 is a top plan view of the face and extension arm of the laterally displaceable member taken along the lines 4--4 of FIG. 3; and.
DETAILED DESCRIPTION
A block-type switch assembly is designed to enable one of a plurality of pushbutton actuators to be depressed from a normal inoperative position to an operative position and at the same time to release or restore to inoperative position an associated pushbutton actuator which has been previously depressed into an operative position. A sliding block-type switch assembly is described and claimed in my U.S. Pat. application, Ser. No. 201,761, filed Nov. 24, 1971, now U.S. Pat. No. 3,727,013 and assigned to the assignee of this application.
In FIG. 1 there is shown a pushbutton switch assembly which utilizes the momentary sliding block-type switch action of the present invention. The switch assembly 10 includes a housing 12 of a molded plastic material which has a coverplate 14 that is secured to the walls of the housing to close off the top thereof. A plurality of pushbutton actuators 16, 17, 18, 19, 20 and 21 are shown slidably positioned in the housing 12. Each pushbutton actuator includes a button portion 22 and a block-like actuator body portion 23 connected to the button portion 22 by arm portion 24. The block-like actuators are held in a spaced relation to each other between a pair of rails 26 to prevent a displaced actuator from contacting an adjacent actuator, thereby facilitating the movement of a selected pushbutton. Each actuator body portion 23 includes a mounted contact member 28 which is biased by a spring 31 and which, upon longitudinal displacement of the pushbutton actuators 16, 17, 18, 19, 20 and 21, contacts a plurality of fixed contacts 29 mounted within the switch housing 12 and having terminals 30 extending outwardly therefrom to complete the electrical circuit. The fixed contact and terminal structure illustrated by FIG. 2 is shown to aid in the description of the invention and it is contemplated that variations and modifications may be effected without departing from the spirit and scope of the novel features described herein. The dimples 32 on the block-type actuators serve to eliminate high and low spots from the parts and create even bearing points on which the actuator can slide along the coverplate 14 thereby further enhancing the ease with which the pushbutton actuator may be operated. Each actuator body portion has a projection at its end, with the angled surfaces such as 34 and 35 acting as cam surfaces when the pushbutton actuator is depressed.
A plurality of wedge shaped displaceable members 36 are mounted in the switch housing on a pair of rails 38. Each of these members is in the form of a multi-sided wedge shaped block, and is preferably constructed of a rigid plastic material having dimensional stability. Also, the displaceable members 36 may contain dimples 39 (FIG. 4) which prevent the displaceable members from having high and low spots, and create even bearing points within the switch assembly. The displaceable members 36 are so positioned within the housing that when a pushbutton (17) is displaced longitudinally, one of the angled cam surfaces 34 and 35 thereon, which are present on the projecting end of each of the actuator body portions 23, engages a matching cam surface 40 on the multi-sided displaceable member 36 to slide the member laterally.
Referring to FIGS. 3 and 4, a spring holder extension arm 42 is molded integral to, and centrally located on, the top side of each of the displaceable members 36. The spring holder extension arm has a lip portion 43 which facilitates anchoring thereto one end of spring 45, and prevents accidental disengagement of the spring from the displaceable member. The spring holder extension arm is formed of the same rigid material as the displaceable member.
As can be seen in FIGS. 1 and 2, the coverplate 14 for the switch contains a plurality of slots 48. These slots 48 are positioned on the coverplate and aligned for receiving each of the spring holder extension arms 42 on the displaceable members 36, and for permitting unobstructed movement of the displaceable members in the momentary switch assembly as the members traverse horizontally on the rails 38. Additionally, located on the edge of the coverplate are notches 50 which provide fixed anchor points for the spring on the momentary switch assembly. These anchor points are bidirectional in that the spring may be adjusted to permit the lateral movement of the displaceable member in either direction.
The spring 45 is first anchored in the slots in the edge of the coverplate 14 as shown in FIG. 1. The spring holder extension arm on the displaceable member establishes a second movable anchor point for the spring on the momentary circuit (FIG. 2). It is contemplated by this invention that the return spring can be constructed of any resilient material which acts as a return means to spring bias the laterally displaced member to its original unactuated position. It is further contemplated by this invention that any type spring holder extension arm which establishes a fixed anchor point for the spring on the displaceable member is within the spirit of this invention.
In the operation of the switch assembly as shown in FIG. 1, spring 45 is attached to the extension arm 42 on displaceable member 36 and anchored in notch 50. As the pushbutton 17 is depressed, the block-like actuator 23 engages displaceable member 36. As the pushbutton is further depressed, cam surface 35 slidably engages cam surface 40 of displaceable member 36 thereby causing a lateral movement of the displaceable member. Simultaneously with this movement, the mounted contact member 28 is completing the electrical circuit by engaging the fixed contacts 29. As member 36 is laterally displaced, it engages and moves adjacent displaceable members, thereby increasing the tension on spring 45. When the resultant pressure is removed from pushbutton 17, the spring biased displaceable member 36 is returned to its original position and the corresponding adjacent displaceable members are also returned to their original unactuated position. As displaceable member 36 is returned to its original unactuated position, the camming effect is reversed and the actuator body portion 23 and pushbutton 17 are returned to their unactuated position thereby breaking the switching circuit and completing the switching action of the switch assembly.
Importantly, the spring 45 is manually adjustable and may be anchored in any notch on the coverplate and anchored to any displaceable member as desired. If it is desired for a particular switching action for the momentary switch position to be variable, the spring may be manually removed and attached to another displaceable member without removal of the coverplate because the means for spring biasing the members are externally located on the switch housing. Thus, the anchoring position for the spring relative to the spring holder extension arm determines the number of switch positions that are momentary in the switch assembly.
What has been described therefore, is a pushbutton switch assembly utilizing spring biased sliding block-type action wherein the pushbutton is returned to its unactuated condition when the pressure on the pushbutton is released. This unique switch assembly is adjustable to permit selection of any desired momentary switch position and any number of momentary switch positions.