US3358091A - Multiple switch - Google Patents

Multiple switch Download PDF

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Publication number
US3358091A
US3358091A US558733A US55873366A US3358091A US 3358091 A US3358091 A US 3358091A US 558733 A US558733 A US 558733A US 55873366 A US55873366 A US 55873366A US 3358091 A US3358091 A US 3358091A
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actuator
wafers
housing
switch
cavity
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US558733A
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Charles A Dyle
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Marmon Co
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Hammond Corp
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Assigned to MARMON COMPANY reassignment MARMON COMPANY ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: HAMMOND CORPORATION
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H13/00Switches having rectilinearly-movable operating part or parts adapted for pushing or pulling in one direction only, e.g. push-button switch
    • H01H13/02Details
    • H01H13/12Movable parts; Contacts mounted thereon
    • H01H13/14Operating parts, e.g. push-button

Definitions

  • This invention relates to multiple switches which are made up of a multiplicity of side by side identical units.
  • the switch mechanism of this invention will have other uses, the example given is intended for incorporation in an electric organ for providing a percussive arpeggio effect in the manner explained in the patent application of Alan Young, Ser. No. 415,682.
  • each of the switches has an actuator which in effect is a miniature playing key, the group of these playing keys constituting a miniature keyboard.
  • the specific multiple switch to be described is comprised of sixty individual switches in stacked relation, each of the individual switches being about Q7/16 of an inch thick. The stack of switches, therefore, in such organ control use, covers a span of five octaves of notes, one note being assigned to each of said switches.
  • Another object is to provide a novel switch of the above type which is extremely easy to actuate rapidly.
  • FIG. l is a front elevation of the multiple switch of this invention.
  • FiG. 2 is a vertical transverse sectional view which may be considered as taken in the direction of the arrows substantially along the line 2-2 of FIG. 1;
  • FIG. 3 is a front View of the major portion of one ofthe switches before it has been put into its enclosure.
  • FIG. 4 is a top view of the multiple switch of FIG. l with a portion of the exterior housing broken away so as to disclose the internal structure.
  • the multiple switch is comprised of a channel section molded of plastic material which houses and aligns a multiplicity-in the present instance 60-of individual switch wafers 12. These wafers are made up of a plastic molded housing element 14, the electrical switch elements, and the arrangement for actuating the contacts.
  • Each ofthe waferlike housings 14 is formed as a shallow tray having a plane back face 16 and an opposite or front face 18 which is formed reentrantly to provide a cavity 2t). Beyond the limits of the cavity 2t), the front face 18 is provided with a pair of outstanding molded alignment pins 22 which fit into sockets 24 in the back surface 16 of the adjacent wafer wlu'ch keeps the wafers in the stack in general alignment pending the final assembly.
  • the fiat back face 16 of each wafer closes the cavity Ztl of the adjacent wafer, the cavity at the end of the stack being closed by a cover plate 26.
  • each of the wafers 14 has a hole 28 therethrough. When the wafers are stacked, a threaded rod 30 is passed through the aligned holes 28, and nuts 32 at each end are tightened as necessary to secure the stack.
  • Each Wafer 14 is provided with a fixed contact member 34 formed of a strip of appropriate metal.
  • This strip has an outstanding portion 36 forming a solder terminal, a portion 38, generally normal thereto, which lies externally against the left edge of the housing, as seen in FIG. 2, a Z-shaped section lli which passes through a slot in the side wall of the housing, and a portion 42, parallel to portion 38, which passes through a second slot so as to lie partially within and partially outside the housing.
  • This preformed contact strip is simply pushed into place during assembly and remains because of its springy clamping action against the surfaces it engages.
  • the portion of the strip which lies within the cavity 20 serves as the switch fixed contact.
  • the movable contact is provided by a similar strip 45 which extends from its solder terminal end 46, through a slot and into the cavity 2t) where it is bent around a pin d3 so as to fix the strip in place. Beyond the pin 48, the strip is free and is bent to the left and then to the right to form a bight at Sti which is near the fixed contact strip 34.
  • the free end 52 of the contact strip is positioned to be engaged by an offset nose 54 formed as a portion of an actuator slide 56.
  • This slide has left and right ends (FIG. 2) 53 and 60, respectively, which pass through fitted slots in the housing wall so that it is retained in place but is free for limited movement from right to left.
  • the right end 60 extends beyond the housing wall about 1/16 inch to provide an end surface 62 which is pressed to close the switch, the spring action of the movable switch blade 45 serving to open the switch and restore the position of the actuator 56 when pressure is released. Since the far side of the actuator is against the inside wall of the housing, this far side, indicated at 64 in FIG. 3, is spaced from the right edge of the wafer as seen in FIG. 3 by the amount of the wall thickness. To balance this, the right portion of the end 60 is cut away as at 66 so that the remaining portion of the end 62 is centered when the cavity in the housing is closed by the next adjacent wafer.
  • a pair of outstanding pillars 63 and 76, near the top and 'bottom respectively, are slotted ⁇ as at 72. and 74 so that these slots are in alignment with the actuator exposed end 62. These slots loosely accommodate the ⁇ slender ends i6 of rollers 86, the 4large diameter portion of the rollers being loosely confined between the pillars 68-70.
  • the -top slot 72 is only slightly deeper than the diameter of the roller end 76, whereas the lower slot '74 is considerably deeper and the length of the pillars 68- '70 is such that when the roller Si) is in place, it rests against the actuator end 62 with both small roller ends 76 approximately flush with the ends of the pillars 68-70. When a finger is run over the roller, it tilts inwardly about its upper pivot at 72 and presses the actuator end 62 and closes the switch.
  • a strip of felt 82 underlies the upper ends of the rollers and may be secured across the aligned faces of the wafers after they have been stacked.
  • the wafers are stacked, preferably in some sort of fixture, the end clo- E sure 26 is put in place, and the threaded rod 30 is passed through the stack. Proper stacking and alignment is insured by the interengaging elements Z2 and 24. If a fixture is used, this of course also helps. With the rod 30 in place, the nuts 32 are threaded thereon and tightened. The electrical connections are then made to the terminals 46 and 36.
  • the strip of felt 82 ⁇ is cemented in place and the stack oriented with the slots 72 and 74 uppermost.
  • This channel which may be formed as an extrusion, has rails 86 and 88 along its interior surface which fit aligned slots 90 ⁇ formed in tabs 92 at the ends of the wafers.
  • the channel also has inturned parallel edges 94 which overlie the ends of the pillars 68 and 70 and close the ends of the slots 72 and 74, thus retaining the rollers S0.
  • the ends of the channel are partially closed by caps 96 which have holes which tit over the rod 30, the caps being retained by nuts 98. Space is provided behind the caps 96 for passage of the electrical cables 100 to the switch contacts, and the front surfaces of the channel and end caps are, in the present instance, formed to provide an attractive facia 102.
  • the specific device shown has a pair of outstanding strips 104 which are extruded as a portion ofthe channel for this purpose.
  • rollers 8i have been used in the present instance Y as viinger contacting elements, it will be appreciated that smooth strips with a well rounded outwardly facing surface would serve much the same purpose.
  • a multiple switch organization comprised of a multiplicity of identical side-by-side stacked switch wafers
  • each of said wafers comprising a thin housing of insulating material having a at back surface and a front reentrant surface providing a cavity therein, so that the back of one of said housings closes the cavity in the adjacent housing in the stack, a stationary contact strip and a iiexible contact strip having a movable portion both housed within said cavity, said strips having terminal portions xed in said housing and passing through the wall thereof, an actuator mounted to move transversely through said housing and bring said movable contact portion against said stationary contact strip when one end of said iactuato-r is subjected to pressure, said exible strip acting to restore said actuator after the pressure is removed, each of said housings being formed externally to provide aV pair of slots in alignment with each other and with the actuator said one end, a iinger engaging element having portions guided in said slots and overlying said actuator one end, a channel member enclosing the major portion of said stack of switch wafers and having elements overlying said slots to prevent loss of said finger
  • each of said finger engaging elements is a roller having ends of reduced diameter t0 fit loosely in said slots.
  • each of said wafers is formed on the front and back surfaces with elements for engaging the adjacent wafer in the stack to promote approximate alignment throughout the stack of wafers.
  • each of said wafers is formed on the front and back surfaces with elements for engaging the adjacent Wafer in the stack -to promote approximate alignment throughout the stack of wafers.
  • a multiple switchtorganization comprised of a rnultiplicity of identical stacked switch wafers, each of said wafers comprising a thin housing of insulating material having a cavity formed in one face thereof, the cavity in said one face being closed by the other face of the adjacent wafer in said stack, a pair of electrical contacts housed in each of -said cavities, a contact actuator for each set of contacts extending into its respective housing, said actuators having exposed elements in alignment when said wafers are stacked, a movable finger engaging element for each of said exposed elements, an enclosure for said stacked wafers and a portion of said finger engaging elements, said enclosure exposing a portion of each of said finger engaging elements, said enclosure exposing a portion of each of said finger engaging elements for operation of its respective switch.

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  • Push-Button Switches (AREA)

Description

Dec. l2, 1967 c. A. DYLE 3,358,091
MULTIPLE SWITCH Filed June 20, 1966 United States Patent Gfice 3,358,091 Patented Dec. 12, 1967 3,358,091 MULTIPLE SWITCH Charles A. Dyle, Chicago, lill., assigner to Hammond Corporation, a corporation of Delaware Filed .lune 2t), 1966, Ser. No. 558,733 S Claims. (Cl. v- 5) ABSTRACT 0F THE DISCLOSURE A multiple switch assembly including identical thin stacked switch wafers, each having a finger actuator, the actuators being arranged in a row, and a housing for the stack exposing the row of actuators.
This invention relates to multiple switches which are made up of a multiplicity of side by side identical units. Although the switch mechanism of this invention will have other uses, the example given is intended for incorporation in an electric organ for providing a percussive arpeggio effect in the manner explained in the patent application of Alan Young, Ser. No. 415,682.
In general, what is required for that purpose is a row of very closely spaced switches, so organized that by running a finger along the row, the switches can be actuated in succession very rapidly in either direction and with little effort. In the arpeggio system mentioned above, each of the switches has an actuator which in effect is a miniature playing key, the group of these playing keys constituting a miniature keyboard. Without intending to be limitative of the invention, but rather for the purpose of orientation, it may be stated that the specific multiple switch to be described is comprised of sixty individual switches in stacked relation, each of the individual switches being about Q7/16 of an inch thick. The stack of switches, therefore, in such organ control use, covers a span of five octaves of notes, one note being assigned to each of said switches.
It is an object of the invention to provide a novel multiple switch made up principally of individual switch elements which can be manufactured at low cost, is reliable, and presents an attractive appearance.
Another object is to provide a novel switch of the above type which is extremely easy to actuate rapidly.
Other objects and advantages will appear from the following description of a preferred embodiment of the invention.
In the drawings in which similar characters of reference refer to similar elements throughout the several views,
FIG. l is a front elevation of the multiple switch of this invention;
FiG. 2 is a vertical transverse sectional view which may be considered as taken in the direction of the arrows substantially along the line 2-2 of FIG. 1;
FIG. 3 is a front View of the major portion of one ofthe switches before it has been put into its enclosure; and
FIG. 4 is a top view of the multiple switch of FIG. l with a portion of the exterior housing broken away so as to disclose the internal structure.
In general, the multiple switch is comprised of a channel section molded of plastic material which houses and aligns a multiplicity-in the present instance 60-of individual switch wafers 12. These wafers are made up of a plastic molded housing element 14, the electrical switch elements, and the arrangement for actuating the contacts.
Each ofthe waferlike housings 14 is formed as a shallow tray having a plane back face 16 and an opposite or front face 18 which is formed reentrantly to provide a cavity 2t). Beyond the limits of the cavity 2t), the front face 18 is provided with a pair of outstanding molded alignment pins 22 which fit into sockets 24 in the back surface 16 of the adjacent wafer wlu'ch keeps the wafers in the stack in general alignment pending the final assembly. In the assembly of the stack of wafers, it will be appreciated, the fiat back face 16 of each wafer closes the cavity Ztl of the adjacent wafer, the cavity at the end of the stack being closed by a cover plate 26. To hold the stack together, each of the wafers 14 has a hole 28 therethrough. When the wafers are stacked, a threaded rod 30 is passed through the aligned holes 28, and nuts 32 at each end are tightened as necessary to secure the stack.
Each Wafer 14 is provided with a fixed contact member 34 formed of a strip of appropriate metal. This strip has an outstanding portion 36 forming a solder terminal, a portion 38, generally normal thereto, which lies externally against the left edge of the housing, as seen in FIG. 2, a Z-shaped section lli which passes through a slot in the side wall of the housing, and a portion 42, parallel to portion 38, which passes through a second slot so as to lie partially within and partially outside the housing. This preformed contact strip is simply pushed into place during assembly and remains because of its springy clamping action against the surfaces it engages. The portion of the strip which lies within the cavity 20 serves as the switch fixed contact.
The movable contact is provided by a similar strip 45 which extends from its solder terminal end 46, through a slot and into the cavity 2t) where it is bent around a pin d3 so as to fix the strip in place. Beyond the pin 48, the strip is free and is bent to the left and then to the right to form a bight at Sti which is near the fixed contact strip 34. The free end 52 of the contact strip is positioned to be engaged by an offset nose 54 formed as a portion of an actuator slide 56. This slide has left and right ends (FIG. 2) 53 and 60, respectively, which pass through fitted slots in the housing wall so that it is retained in place but is free for limited movement from right to left. The right end 60 extends beyond the housing wall about 1/16 inch to provide an end surface 62 which is pressed to close the switch, the spring action of the movable switch blade 45 serving to open the switch and restore the position of the actuator 56 when pressure is released. Since the far side of the actuator is against the inside wall of the housing, this far side, indicated at 64 in FIG. 3, is spaced from the right edge of the wafer as seen in FIG. 3 by the amount of the wall thickness. To balance this, the right portion of the end 60 is cut away as at 66 so that the remaining portion of the end 62 is centered when the cavity in the housing is closed by the next adjacent wafer.
A pair of outstanding pillars 63 and 76, near the top and 'bottom respectively, are slotted `as at 72. and 74 so that these slots are in alignment with the actuator exposed end 62. These slots loosely accommodate the `slender ends i6 of rollers 86, the 4large diameter portion of the rollers being loosely confined between the pillars 68-70. The -top slot 72 is only slightly deeper than the diameter of the roller end 76, whereas the lower slot '74 is considerably deeper and the length of the pillars 68- '70 is such that when the roller Si) is in place, it rests against the actuator end 62 with both small roller ends 76 approximately flush with the ends of the pillars 68-70. When a finger is run over the roller, it tilts inwardly about its upper pivot at 72 and presses the actuator end 62 and closes the switch.
So as to prevent rattling of the rollers and help to restore them to the unactuated position, a strip of felt 82 underlies the upper ends of the rollers and may be secured across the aligned faces of the wafers after they have been stacked.
After the contacts 45 and 34, and the actuators 56 have been located in the individual wafers, the wafers are stacked, preferably in some sort of fixture, the end clo- E sure 26 is put in place, and the threaded rod 30 is passed through the stack. Proper stacking and alignment is insured by the interengaging elements Z2 and 24. If a fixture is used, this of course also helps. With the rod 30 in place, the nuts 32 are threaded thereon and tightened. The electrical connections are then made to the terminals 46 and 36.
The strip of felt 82` is cemented in place and the stack oriented with the slots 72 and 74 uppermost. The rollers Si) .are then set in their slot-s 72-74 and the assembly is slid in an endwise direction into a channel 84. This channel, which may be formed as an extrusion, has rails 86 and 88 along its interior surface which fit aligned slots 90 `formed in tabs 92 at the ends of the wafers. The channel also has inturned parallel edges 94 which overlie the ends of the pillars 68 and 70 and close the ends of the slots 72 and 74, thus retaining the rollers S0. The ends of the channel are partially closed by caps 96 which have holes which tit over the rod 30, the caps being retained by nuts 98. Space is provided behind the caps 96 for passage of the electrical cables 100 to the switch contacts, and the front surfaces of the channel and end caps are, in the present instance, formed to provide an attractive facia 102.
Although any suitable mounting arrangement for the multiple switch can be p-rovided, the specific device shown has a pair of outstanding strips 104 which are extruded as a portion ofthe channel for this purpose.
With the device in place, at any time it is desired to actuate all or a portion of the switches in succession it is necessary merely to run a finger along the rollers 80. Al-
though rollers 8i) have been used in the present instance Y as viinger contacting elements, it will be appreciated that smooth strips with a well rounded outwardly facing surface would serve much the same purpose.
From the above description of a preferred embodiment of the invention, it will be appreciated that variations in the structure may be made without: departing from the scope or spirit of the invention, and that, therefore, the scope of the invention is to be determined from the scope of the following claims.
Having described the invention, what I claim as new and useful and desire to secure by Letters Patent of the United States is:
1. A multiple switch organization comprised of a multiplicity of identical side-by-side stacked switch wafers,
veach of said wafers comprising a thin housing of insulating material having a at back surface and a front reentrant surface providing a cavity therein, so that the back of one of said housings closes the cavity in the adjacent housing in the stack, a stationary contact strip and a iiexible contact strip having a movable portion both housed within said cavity, said strips having terminal portions xed in said housing and passing through the wall thereof, an actuator mounted to move transversely through said housing and bring said movable contact portion against said stationary contact strip when one end of said iactuato-r is subjected to pressure, said exible strip acting to restore said actuator after the pressure is removed, each of said housings being formed externally to provide aV pair of slots in alignment with each other and with the actuator said one end, a iinger engaging element having portions guided in said slots and overlying said actuator one end, a channel member enclosing the major portion of said stack of switch wafers and having elements overlying said slots to prevent loss of said finger engaging elements, and said channel member exposing at least a portion of all of said finger engaging elements.
2. The switch called for in claim 1 in which each of said finger engaging elements is a roller having ends of reduced diameter t0 fit loosely in said slots.
3. The switch called for in claim 1 in which each of said wafers is formed on the front and back surfaces with elements for engaging the adjacent wafer in the stack to promote approximate alignment throughout the stack of wafers.
4. The switch called for in claim 3 in which said channel member and said wafers have mutually interengaging elements to promote precise alignment of said wafers with each other and with saidchannel member. t
5. The switch called for in claim 2 in which each of said wafers is formed on the front and back surfaces with elements for engaging the adjacent Wafer in the stack -to promote approximate alignment throughout the stack of wafers.
6. The switch called for in claim 5 in which said channel member and said wafers have mutually interengaging elements to promote precise alignment of said wafers with each other and with said channel member.
7. A multiple switchtorganization comprised of a rnultiplicity of identical stacked switch wafers, each of said wafers comprising a thin housing of insulating material having a cavity formed in one face thereof, the cavity in said one face being closed by the other face of the adjacent wafer in said stack, a pair of electrical contacts housed in each of -said cavities, a contact actuator for each set of contacts extending into its respective housing, said actuators having exposed elements in alignment when said wafers are stacked, a movable finger engaging element for each of said exposed elements, an enclosure for said stacked wafers and a portion of said finger engaging elements, said enclosure exposing a portion of each of said finger engaging elements, said enclosure exposing a portion of each of said finger engaging elements for operation of its respective switch.
8. The switch called for in claim 7 in which said enclosure and said wafers have mutually interengaging elements to promote alignment of said wafers with respect to each other and with said enclosure.
No references cited.
ROBERT K. SCHAEFER, Primary Examiner..
J. R. SCOTT, Assistant Examiner.

Claims (1)

1. A MULTIPLE SWITCH ORGANIZATION COMPRISED OF A MULTIPLICITY OF IDENTICAL SIDE-BY-SIDE STACKED SWITCH WAFERS, EACH OF SAID WAFERS COMPRISING A THIN HOUSING OF INSULATING MATERIAL HAVING A FLAT BACK SURFACE AND A FRONT REENTRANT SURFACE PROVIDING A CAVITY THEREIN, SO THAT THE BACK OF ONE OF SAID HOUSINGS CLOSES THE CAVITY IN THE ADJACENT HOUSING IN THE STACK, A STATIONARY CONTACT STRIP AND A FLEXIBLE CONTACT STRIP HAVING A MOVABLE PORTION BOTH HOUSED WITHIN SAID CAVITY, SAID STRIPS HAVING TERMINAL PORTIONS FIXED IN SAID HOUSING AND PASSING THROUGH THE WALL THEREOF, AN ACTUATOR MOUNTED TO MOVE TRANSVERSELY THROUGH SAID HOUSING AND BRING SAID MOVABLE CONTACT PORTION AGAINST SAID STATIONARY CONTACT STRIP WHEN ONE END OF SAID ACTUATOR IS SUBJECTED TO PRESSURE, SAID FLEXIBLE STRIP ACTING TO RESTORE SAID ACTUATOR AFTER THE PRESSURE IS REMOVED, EACH OF SAID HOUSINGS BEING FORMED EXTERNALLY TO PROVIDE A PAIR OF SLOTS IN ALIGNMENT WITH EACH OTHER AND WITH THE ACTUATOR SAID ONE END, A FINGER ENGAGING ELEMENT HAVING PORTIONS GUIDED IN SAID SLOTS AND OVERLYING SAID ACTUATOR ONE END, A CHANNEL MEMBER ENCLOSING THE MAJOR PORTION OF SAID STACK OF SWITCH WAFERS AND HAVING ELEMENTS OVERLYING SAID SLOTS TO PREVENT LOSS OF SAID FINGER ENGAGING ELEMENTS, AND SAID CHANNEL MEMBER EXPOSING AT LEAST A PORTION OF ALL OF SAID FINGER ENGAGING ELEMENTS.
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