US3485976A - Pressure actuated switch and plug assembly - Google Patents

Pressure actuated switch and plug assembly Download PDF

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US3485976A
US3485976A US682960A US3485976DA US3485976A US 3485976 A US3485976 A US 3485976A US 682960 A US682960 A US 682960A US 3485976D A US3485976D A US 3485976DA US 3485976 A US3485976 A US 3485976A
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switch
plug
housing
assembly
bellows
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Brian Ronald Reuter
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Consolidated Engineering Co Inc
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Consolidated Engineering Co Inc
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00Switches operated by change of a physical condition
    • H01H35/24Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow

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  • This invention relates to pressurized switch and plug assemblies of the type which include in assembled relationship switch means and pressure sensitive control means adapted to be insertably connected into plug means in manner to complete connection to sources of pressurized gas which actuate the switch moving control means, and in manner to connect the switch means conductors switching circuits to the respective negative and positive sides of sources of electrical power; this applica tion being a continuation-in-part of co-pending application Ser. No. 544,353,, filed Apr. 14, 1966, now Patent No. 3,352,984, for Pressure Actuated Switch and Plug Assembly, Notice of Allowance having been mailed thereon under mailing date of June 27, 1967.
  • control and switch assembly includes an index tab whereby a plurality of prongs insertable into the plug to establish frictional connection therewith may be orientated so that those prongs additionally carrying current from the switch connect with corresponding conductors into the plug.
  • the invention provides a switch and plug assembly of this class; switch and control means being cooperatively adapted with the plug means in manner that the plug means may be disposed in any selective angularly extending, vertical or horizontal plane, as the pressurized gas conduit extends sidewardly from the assembly, as connected sidewardly into the bellows housing.
  • the invention provides a switch and plug assembly of this class with switch and control means being of inexpensive construction since the base and plug may be substantially simplified with the plug adapted to be more readily installed in its supporting means, in whatever manner the supporting means may be disposed in space.
  • FIG. 1 is a small scale elevational view showing a switch and plug assembly in relation to an appropriately supported plug and with a pressurized gas conduit being shown in relation to the assembly;
  • FIG. 2 is a large scale sectional elevational view showing details of a switch and plug assembly correspondingly as shown to small scale in FIG. 1;
  • FIG. 3 is a bottom view taken along lines 33 of FIG. 2;
  • FIG. 4 is a conventional diagram of a single pole, double throw switch corresponding with the switch indicated as being encased in FIG. 2;
  • FIG. 5 is a small scale elevational view of another embodiment of switch and plug assembly in relation to a horizontally disposed plug support and with the pressurized gas conduit being shown connected sidewardly into the assembly;
  • FIG. 6 is a large scale sectional elevational view showing details of a switch and plug assembly correspondingly as shown to small scale in FIG. 5;
  • FIG. 7 is a bottom view taken along lines 77 of FIG. 6;
  • FIG. 8 is a conventional diagram of a single pole, double throw switch corresponding with the switch indicated as being encased in FIG. 6.
  • a pressure actuated switch and plug assembly 10 as shown in FIG. 1, includes an assembly case or housing 11 which is supported upon, and connected into, a plug 12 which is in turn supported by a plate, wall or base 13.
  • the switch within the housing 11 functi ns in correspondence with the switch 50 shown in FIG. 1 of co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus, filed J an. 3, 1965, and correspondingly conductors 14a, 15a and 16a, as shown in FIG. 1, can connect respectively with a negative source and two parallel positive source conductor lines.
  • a conduit 17 conveys a pressurized gas, as air, from a T 18 in a compressed gas or air conduit 19, upwardly to actuate the switch, as will be hereinbelow described.
  • a compressed gas or air conduit 19 may correspond functionally with any conduit which conveys an operative gas or compressed air, as for instance the operative air conduit shown in FIG. 1 of the aforesaid co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus filed J an. 3, 1965.
  • the assembly housing 11 includes a base or bottom closure 20 which includes lowermost a metallic box 21 which seats upon the plug 12, the box being of rectangular cross-section as indicated in FIG. 3.
  • a comparatively large central bore 23 is provided through the bottom of a metallic box 21 as indicated in FIGS. 2 and 3.
  • a plastic or insulative base 24 seats within the metallic box 21, and oppositely disposed connection blocks 25, as of metal, are provided whereby the box 21 may be securely connected to the assembly housing 11, as by machine screws 26 which pass through the housing 11 and box 21 and threadably into the connection blocks 25.
  • the base block 27 of a bellows housing 28, to be hereinbelow described, seats centrally upon the upper surface of the plastic base 24 and a compressed gas communication tube 29 is threadably connected centrally into the base block 27 while the plastic base 24 may be moulded around the tube 29 which further extends downwardly through the bore 23 in the bottom of the box 21.
  • the tube 29 has a bore 32 passing centrally downwardly thereinto to communicate with lateral ports 33 provided slightly above the closed lower end of the tube. Also, the tube 29 has an annular groove around a part thereof which slides in the conduit head member 30, an O-ring 34 being provided in the annular groove to insure closa'bly sealed communication between the compressed gas conduit 17 and the interior of the bellows housing 28 thereabove.
  • a plurality (preferably eight) of metallic tubes or prongs 35 are moulded into, or tightly fitted through the plastic base 24 and extend downwardly therebelow, bores 36 being provided in the plug 12 to receive the prongs.
  • Metallic conductor tabs extend upwardly from the under surface of the plug 12 and into the plug to make metallic or electrical contact with the prongs 35, three of the four tabs shown in FIG. 2 being indicated by the respective reference numerals 14a, 15a and 16a.
  • Insulated conductors 14b, 15b and 16b to be further described hereinbelow, have the lower ends of their metallic conductor wires soldered into respective prongs 35 which communicate with, or carry circuit to the respective tabs 14a, 15a and 16a.
  • a material as Chico or a plastic as epoxy, or any suitable hardenable substance 37 is provided within the housing 11 to fill the space above the plastic base 24 up to the level of the tops of the blocks 25 and around the bellows assembly base block 27 and such substance 37 hardens about the blocks 25 and moulds thereinto the insulated lower end portions of the respective conductors 14b, 15b and 16b.
  • the bellows housing 28 includes a central member or body 38 having the lower end 39 thereof bored upwardly and externally threaded for connection into the aforesaid block 27, while a larger diameter portion thereabove is bored downwardly to a larger diameter, there being a communication port 40 provided through the partition wall thus resulting.
  • a bellows 41 of conventional design is provided with its upper end 42 connected, as by brazing, to the inner wall or surface of the housing body 38; the bellows extending downwardly and then recurved to extend upwardly, as best shown in FIG. 2.
  • the inner upper part of the bellows 41 includes an annular part 43 to provide a shoulder and a cylindrical portion 44 having a closed upper end which extends upwardly centrally from the annular shoulder 43.
  • the upper end of the bellows housing body 38 has internal threads 45 therein to threadably receive the externally threaded lower end of the adjustment gland 46 which is counterbored so that the upper end of a spring 47 may seat therein, the lower end of the spring 47 bearing upon an annular disc 48 which is bored to receive the bellows upper end 44 therethrough while the disc 48 seats upon the bellows shoulder 43.
  • a closure plunger 50 extends slidably sealably through a bore 49 provided in the gland 46, the lower end of such plunger seating upon the closed upper end of the bellows inner cylindrical upper portion 44.
  • a single pole, double throw switch 51 is indicated occupying the upper part of the space within the casing or assembly housing 11 and such switch 51 may include a bracket 52 supported by the bellows housing 38, or optionally, or additionally the casing 53 of the switch 51 may be located, and/or supported by screws 54 extending inwardly from the housing or casing 11.
  • the single pole, double throw switch 51 is shown diagrammatically in FIG. 4 as including a post 56 from which extends a first conductor, as the insulated conductor 14b, also a switch arm 57 is indicated as being pivotally mounted on the post 56. Also, an upper post 58 and a lower post 59 are included to provide respective upper and lower contacts 60, 63, from which extend, respectively, the insulated conductors 15b, 16b.
  • the posts 56, 57 and 59 are shown in FIG. 2 as extending above the switch casing 53, and as having the respective insulated conductors 14b, 15b and 16!: extending therefrom, such conductors, as aforesaid, being shown lower in FIG. 2 as they enter the putty or hardenable material 37 of the base assembly 20.
  • a snap action plunger 61 bears upwardly against the pivoted switch arm 57 and downwardly provides a point 62, also as shown in FIG. 2, which is contacted by the bellows actuated closure plunger 50, as will be hereinbelow described.
  • the upper member or conduit head 30 of the compressed gas conduit 17 has an externally threaded tubular valve 64 threadably received thereinto, such valve body providing a seat 65 therein, while a seating element 66 extends through the hollow valve 64 so that a head 67 at the upper end of the stem bears against the lower end face of the tube 29 thus to maintain the seating element 68 unseated under normal operative conditions, and until such time as the tube 29, comprising part of the assembly above the plug 12, may be removed, as for repair or disassembly. However, when such tube 29 is removed, the valve element 68 on the valve stem 66 may seat upwardly against the valve seat 65, and thus prevent escape of any compressed gas from the conduit 17.
  • the plurality of tubes or prongs 35 hereinabove described as extending downwardly from the plastic base 24 of the base assembly or bottom closure 20 are equally angularly spaced apart and equally radially distant from a central, vertical axis through the base, as best indicated in FIG. 3. Also, as shown in black in FIG. 3, only certain of these prongs 35 are used to have the conductor wires from the insulative conductors 14b, 15b, 16b, from the switch 51 thereabove, electrically connected thereinto, while the other tubes or prongs serve only as frictionally engaging connection members within the bores through the plug 12.
  • the prongs 35 are numbered consequently from No. 1 to No. 8 in a clockwise direction.
  • an index tab 55 is shown in FIG. 3 extending radially inwardly into the metallic box bottom bore 23.
  • This tab 55 may be used to orientate the relative positions of the numbered prongs in assembly, and as shown in FIG. 3 it is disposed between the prongs No. 1 and No. 8. correspondingly, as these prongs are inserted into the respectively numbered bores or receptacles in the plug 12, it may be known that prongs No. 2, No. 5 and No. 7, indicated in black in FIG. 3, are inserted in a proper plug bore 36 to carry electrical circuit to those respective tabs 14a, 15a and 16a which have been wired to connect with predetermined circuits, as from a negative and parallel positive sides of a source of electrical power.
  • FIGS. 5-8 the construction of switch and upper part of bellows housing and parts assembled therein are shown to be essentially of the same construction as these elements are shown to be constructed in FIGS. 1-4. Differences enter in FIGS. 5-8 in that the compressed gas (air) inlet enters sidcwardly through the assembly case or housing to pass into a hollow connection means or fitting which communicates with the interior of the bellows housing.
  • the plastic or insulated base of the invention may be of simpler construction as it only receives therethrough the conductors from the switch, such conductors connecting into the metallic tubes carrying the metallic tabs of the plug.
  • the pressure actuated switch and plug assembly 70 shown in FIGS. 5-8 includes an assembly case or housing 71 supported above a plug 72 with switch elements functioning correspondingly as those of the switch 50 shown in FIG. 1 of co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus, filed J an. 3, 1966, and which issued Nov. 28, 1967, as Patent No. 3,355,221.
  • a plate, wall or base 73 supports the plug 72 and insulated conductors 74b, 75b, 76b connect respectively with a negative source and two parallel positive source conductor lines.
  • the assembly housing 71 having bottom closure 80 includes a metallic box 81 which seats upon the plug 72, as shown in FIG. 6.
  • a comparatively large central bore 83 is provided through the bottom of the metallic box 81, and a plastic or insulative base 84 seats within the box 81 which has a centrally disposed post or round depending member 89 to be manually pressed into a central bore 79 through the plug 72.
  • Oppositely disposed connection blocks 85 are provided in slots in the periphery of a layer of hardenable, plastic like substance 97 comprising an insulative layer above the base flange 84, whereby machine screws 86 may be passed through the housing 71 and box 81 into the connection blocks 85 to effect assembly.
  • the block or fitting 87 is bored and double counterbored with the upper or larger counterbore having internal threads 82 therein, threadably to receive the externally threaded lower end 99 of a hollow bellows housing 88.
  • the base block or fitting 87 provides a sidcwardly extending, internally threaded bore 93 which communicates with the inner, lower bore 92 in the block or fitting 87, and which receives the inner part of a compressed gas inlet fitting 90 therein.
  • a flexible tubing 91 extends to a conventional check valve 94 of the type with valve element spring urged seated in direction of the bellows housing base block 87; the check valve housing being rigidly assembled with, and sealably passing through the assembly case or housing 71.
  • a quick disconnect fitting 125 connects a flexible tubing 77 to the outer end of the check valve housing 94 and extends to a terminal fitting 124 by which the tubing 77 is connected into a compressed gas or air manifold 78, as indicated substantially diagrammatically in FIGS. 5 and 6.
  • the plastic flange comprising an insulative base 84 'within the metallic box or bottom closure 81 of the assembly housing 71, has a plurality of equally, angularly spaced apart, metallic tubes or prongs 95 moulded thereinto, or tightly pressed thereinto, to extend downwardly through the central bore 83 through the metallic box 81, and therebelow to pass through correspondingly spaced, aligned bores 96 in the plug 72.
  • Metallic conductor tabs 74a, 75a and 76a are shown in FIG. 6 as extending from below the plug 72 and upwardly connected into the plug 72 to establish electrical connections with the conductor wires of the insulated conductors 74b, 75b, 76b, respectively.
  • the suitable, hardenable substance 97 hereinabove described, that is poured upon the top of the flange 84 to harden around the lower part of the base block or hollow connection means 87, may be a material as Chico or a plastic, as epoxy.
  • Such material 97 as confined within the housing 71, also hardens about, or receives therein, the lower ends of the aforesaid insulative conductors 74b, 75b and 75c, from which the conductor wires therefrom extend downwardly into the aforesaid prongs or sleeves 96.
  • the bellows housing 88 has an upper, cylindrical portion 98 and an externally threaded lower end 99 threadable into the internally threaded, outer counterbore 82, such lower end 99 having a passage 100 therethrough to communicate with the inner counterbore 100a of the connection member 87, the counterbore 100a in turn communicating with the central bore 92 in the connection member 87.
  • a gland 106 having an externally threaded lower end is threadably received into the internally threaded upper end of the bellows housing 88, the lower face periphery of the gland 106 having the upper end 102 of the tubular bellows 101 connected therearound.
  • the bellows 101 extends downwardly from the gland 106 and is then recurved to extend upwardly with its inner upper end comprising an annular part 103 to provide a shoulder and a cylindrical portion 104 extending upwardly, centrally from the annular shoulder 103, the cylinder having a closed upper end, as shown in FIG. 6.
  • the gland 106 is bored and counterbored from the lower end so that a spring 107 may seat upwardly within the counterbore and downwardly upon an annular disc or washer 108 which extends around the cylinder 104 and seats upon the upper face of the annular ring or shoulder 103.
  • a closure plunger extends slidably, sealably through a central bore 109 provided through the gland 106 with the plunger 110 :being of length for the upper end to extend above the top of the gland 106 as the lower end thereof seats upon the closed upper end of the cylinder 104 which comprises the upstanding central part or core of the top closure 103, of recurved inner part of the bellows 101.
  • a single pole, double throw switch 111 in full correspondence with the switch 51 shown in FIGS. 2 and 4, ]includes a bracket 112 by which the switch 111 is mounted upon the upper portion of the cylindrical part 98 of the bellows housing 88, the casing 113 for the switch 111 being connected to the bracket 112 by screws 114.
  • the switch arrangement is the same as that shown diagrammatically in FIG. 4.
  • the first conductor 74b extends from a switch post 116;
  • the second conductor 75b extends from an upper switch post 118; and
  • a third conductor 76b extends from a lower switch post 119.
  • a switch arm 117 is indicated as being pivotally mounted on the switch post 116; an upper contact is cantilevered from the upper switch post 118; and a lower contact 123 is cantilevered from the upper switch post 118; and a lower contact 123 is cantilevered from the lower switch post 119.
  • the posts 116, 118 and 119 extend above the switch casing 113, from whence the respective insulated conductors 74b, 75b and 76b extend, respectively, to the insulated conductors 74b, 75b and 76b, respectively, as they extend upwardly from the upper base element 97.
  • the snap action plunger 121 is indicated as hearing upwardly against the pivoted switch arm 117 and as downwarding providing a point 122, which is contacted by the bellows actuated closure plunger 110', correspondingly as the point 62 in FIG. 2 is contacted by the closure plunger 50.
  • the prongs 95 shown in FIG. 6 and the conductor wires therethrough are indicated by numbers l8, inclusive, while the prongs having the Wires for the insulated conductors 74b, 75b and 76b which figure in the switch action described in FIG. 8, also have the indicating circles filled for diagrammatical purposes, in black.
  • the other prongs 95 not having circuit wires therein serve only as friction a1 members as they engage in the bores 96 in the plug 72.
  • an index tab 115 is shown extending radially inwardly into the metallic box bore 83 for purposes of orientation between the numbered prongs 95 and plug bores 96.
  • a spring 69 may be installed between the bottom inlet openings into the tubular valve 64 and the under side of the head of the seating element 68, to extend around the stem thereof below the head, thus to effect the range of adjustability.
  • the invention is not limited to specific combinations of assemblies of bellows housings with snap action, single pole, double throw switches, but rather includes various embodiments and modifications of assembled switches and control housings. Thus a considerable number of leads in excess of three may extend from the switch assembly, nor is the invention limited to a diaphragm or a bellows as the control means for transmitting gas pressure to operate switch opening and closing. Rather many various arrangements of switches and controls are considered which have a gas conduit means and conductor prongs extending from an assembly base to be guidahly insertable respectively into the gas conduit through a plug and into selected respective circuit conductor means from a source of electrical power.
  • a pressure actuated switch and plug assembly supporting therein a switch arm having a pivoted end, upper and lower, spaced apart contacts, and at least first, second and third conductors extending respectively from said pivoted end and from said contacts, and a snap action plunger having outwardly a contact point, a bellows housing having a bellows across the housing interior, a bored gland adjustably threadable downwardly into said bellows housing to bear upon a spring provided between said gland and said bellows, a closure plunger extending sealably through said gland bore, hollow connection means communicating with the interior of said bellows and providing a compressed gas inlet thereinto, an insulative base to receive the lower end of said hollow connection means therein, said conductors connecting with respective conductor prongs extending from said base, an insulative plug supported to connectably receive said prongs therein to contact respective predetermined circuit completing means extending therefrom, a compressed gas conduit connected into said compressed gas inlet above said base and extending from said inlet to a source of compressed gas
  • a pressure actuated switch and plug assembly as claimed in claim 1 in which a plurality of prongs including conductor prongs extend in circular arrangement from said base, and in which said base provides an indexing tab with relation to which the conductor prongs of said circle may be oriented thereby to connect with the circuit completing means extending from said plug.
  • a pressure actuated switch and plug assembly as claimed in claim 1 which includes in excess of two contacts and conductors therefrom with the contacts each closed and broken by movement of switch arm means.
  • a pressure actuated switch and plug assembly as claimed in claim 1 in which said base comprises lowermost a metallic box to seat on said plug and having a central bore through the bottom for extension of said prongs and said communication tube therethrough, said base being of plastic immediately above said bottom within said box and being comprised of a hardenable material uppermost around said hollow connection means and to mould around said conductors and around metal connection blocks through which said box is connected with an outer housing over said bellows housing and said switch parts and including said base and through which said conduit passes sidewardly above said base.
  • a pressure actuated switch and plug assembly as claimed in claim 1 in which said base is connected to said plug by a plurality of prongs including said conductor prongs, each comprising a metallic tube restrained in said base, with the wires of said conductors being soldered into selective prongs.
  • a pressure actuated switch and plug assembly as claimed in claim 1 in which said bellows extends downwardly from the wall of said bellows housing and is then recurved upwardly to provide a central upstanding projection on which seats said closure plunger.
  • a pressure actuated switch and plug assembly as claimed in claim 1 in which said assembly includes an outer housing for said switch parts and said bellows housing, and in which said switch parts are encased in a casing rigidly disposed with relation to said outer housing and said bellows housing, said conduit passing sidewardly through said housing above said base.

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  • Switches Operated By Changes In Physical Conditions (AREA)

Description

1969 B. R. REUTER 3,485,976
PRESSURE ACTUATED SWITCH AND PLUG ASSEMBLY Filed Nov. 14, 196'? 2 Sheets-Sheet 1 BR IA N R. REu'rER INVENTOR I 7 4-7 E BY ATTORNEY Dec. 23, 19-69 B. R. REUTER PRESSURE ACTUATED SWITCH AND PLUG ASSEMBLY Filed Nov.- 14, 1967 2 Sheets-Sheet 2 I20 r I19 766' 2; III
BRIAN R REUTER INVENTOR BY M ATTORNEY United States Patent 3,485,976 PRESSURE ACTUATED SWITCH AND PLUG ASSEMBLY Brian Ronald Reuter, Houston, Tex., assignor to Consolidated Engineering Company, Houston, Tex. 'Continuation-in-part of application Ser. No. 544,353, Apr. 14, 1966. This application Nov. 14, 1967, Ser. No. 682,360
Int. Cl. H0111 35/40, 37/38 US. Cl. 20083 8 Claims ABSTRACT OF THE DISCLOSURE Assemblies of switches and their plugs are provided with the gas for pressure actuation of the switch in one form passing coaxially upwardly through the switch parts thereabove, and in another form the gas being brought in sidewardly above the plug then to pass upwardly through the switch parts. In either form the pressure sensitive control means and the switch parts actuated thereby are sub-assembled in manner to permit such sub-assemblies to be insertably connected into their respective plugs, thus connecting the conductors switching circuits within the switch to the respective negative and positive sides of sources of electrical power.
This invention relates to pressurized switch and plug assemblies of the type which include in assembled relationship switch means and pressure sensitive control means adapted to be insertably connected into plug means in manner to complete connection to sources of pressurized gas which actuate the switch moving control means, and in manner to connect the switch means conductors switching circuits to the respective negative and positive sides of sources of electrical power; this applica tion being a continuation-in-part of co-pending application Ser. No. 544,353,, filed Apr. 14, 1966, now Patent No. 3,352,984, for Pressure Actuated Switch and Plug Assembly, Notice of Allowance having been mailed thereon under mailing date of June 27, 1967.
It is thus a primary object of this invention to provide an assembled switch and pressure sensitive control means, with the assembly being adapted for insertion in a plug means in manner to connectably complete switch and plug assembly while completing connection to a source of pressurized gas and with conductors to sides of a source of electrical power.
It is also an important object of this invention to provide a switch and plug assembly of this class in which a plurality of prongs extend from the switch and control means assembly to comprise insertable connection means with the plug, with insertion being selective in manner that selective prongs comprising conductors to the switch means connect with corresponding conductors from the respective sides of a source of electrical power.
It is yet a further object of this invention to provide a switch and plug assembly of this class adapted to permit assembled switch and control means to be withdrawn from the plug so that valve means in the actuating pressurized gas conduit through the plug may close to prevent escape of the gas during such disconnection.
It is still a further object of the invention to provide a switch and plug assembly of this class in which the control and switch assembly includes an index tab whereby a plurality of prongs insertable into the plug to establish frictional connection therewith may be orientated so that those prongs additionally carrying current from the switch connect with corresponding conductors into the plug.
It is also an added and important object of the invention to provide a switch and plug assembly of this class in which the pressurized gas delivery or conduit means connects sidewardly into the bellows housing between the bellows and the plug, whereby the construction of the plug may be substantially simplified.
Also, as another object, the invention provides a switch and plug assembly of this class; switch and control means being cooperatively adapted with the plug means in manner that the plug means may be disposed in any selective angularly extending, vertical or horizontal plane, as the pressurized gas conduit extends sidewardly from the assembly, as connected sidewardly into the bellows housing.
Additionally, as a further added object, the invention provides a switch and plug assembly of this class with switch and control means being of inexpensive construction since the base and plug may be substantially simplified with the plug adapted to be more readily installed in its supporting means, in whatever manner the supporting means may be disposed in space.
Other and further objects will be apparent when the specification herein is considered in connection with the drawings, in which:
FIG. 1 is a small scale elevational view showing a switch and plug assembly in relation to an appropriately supported plug and with a pressurized gas conduit being shown in relation to the assembly;
FIG. 2 is a large scale sectional elevational view showing details of a switch and plug assembly correspondingly as shown to small scale in FIG. 1;
FIG. 3 is a bottom view taken along lines 33 of FIG. 2;
FIG. 4 is a conventional diagram of a single pole, double throw switch corresponding with the switch indicated as being encased in FIG. 2;
FIG. 5 is a small scale elevational view of another embodiment of switch and plug assembly in relation to a horizontally disposed plug support and with the pressurized gas conduit being shown connected sidewardly into the assembly;
FIG. 6 is a large scale sectional elevational view showing details of a switch and plug assembly correspondingly as shown to small scale in FIG. 5;
FIG. 7 is a bottom view taken along lines 77 of FIG. 6; and
FIG. 8 is a conventional diagram of a single pole, double throw switch corresponding with the switch indicated as being encased in FIG. 6.
Referring now in detail to the drawings in which like reference numerals are applied to like elements in the various views, a pressure actuated switch and plug assembly 10, as shown in FIG. 1, includes an assembly case or housing 11 which is supported upon, and connected into, a plug 12 which is in turn supported by a plate, wall or base 13. The switch within the housing 11 functi ns in correspondence with the switch 50 shown in FIG. 1 of co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus, filed J an. 3, 1965, and correspondingly conductors 14a, 15a and 16a, as shown in FIG. 1, can connect respectively with a negative source and two parallel positive source conductor lines.
A conduit 17 conveys a pressurized gas, as air, from a T 18 in a compressed gas or air conduit 19, upwardly to actuate the switch, as will be hereinbelow described. Such a compressed gas or air conduit 19 may correspond functionally with any conduit which conveys an operative gas or compressed air, as for instance the operative air conduit shown in FIG. 1 of the aforesaid co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus filed J an. 3, 1965.
The assembly housing 11 includes a base or bottom closure 20 which includes lowermost a metallic box 21 which seats upon the plug 12, the box being of rectangular cross-section as indicated in FIG. 3. A comparatively large central bore 23 is provided through the bottom of a metallic box 21 as indicated in FIGS. 2 and 3. A plastic or insulative base 24 seats within the metallic box 21, and oppositely disposed connection blocks 25, as of metal, are provided whereby the box 21 may be securely connected to the assembly housing 11, as by machine screws 26 which pass through the housing 11 and box 21 and threadably into the connection blocks 25.
The base block 27 of a bellows housing 28, to be hereinbelow described, seats centrally upon the upper surface of the plastic base 24 and a compressed gas communication tube 29 is threadably connected centrally into the base block 27 while the plastic base 24 may be moulded around the tube 29 which further extends downwardly through the bore 23 in the bottom of the box 21.
The compressed gas conduit 17, which includes the conduit 31 from the T 18, also includes an upper member or tubular head 30 which seats within the plug 12 and which therebelow passes threadably through the plug and extends downwardly therebelow as the uppermost member of the aforesaid compressed gas conduit 17, and into which the conduit tubular lower member 31 is threadably connected.
The tube 29 has a bore 32 passing centrally downwardly thereinto to communicate with lateral ports 33 provided slightly above the closed lower end of the tube. Also, the tube 29 has an annular groove around a part thereof which slides in the conduit head member 30, an O-ring 34 being provided in the annular groove to insure closa'bly sealed communication between the compressed gas conduit 17 and the interior of the bellows housing 28 thereabove.
A plurality (preferably eight) of metallic tubes or prongs 35 are moulded into, or tightly fitted through the plastic base 24 and extend downwardly therebelow, bores 36 being provided in the plug 12 to receive the prongs. Metallic conductor tabs extend upwardly from the under surface of the plug 12 and into the plug to make metallic or electrical contact with the prongs 35, three of the four tabs shown in FIG. 2 being indicated by the respective reference numerals 14a, 15a and 16a. Insulated conductors 14b, 15b and 16b, to be further described hereinbelow, have the lower ends of their metallic conductor wires soldered into respective prongs 35 which communicate with, or carry circuit to the respective tabs 14a, 15a and 16a. A material as Chico or a plastic as epoxy, or any suitable hardenable substance 37 is provided within the housing 11 to fill the space above the plastic base 24 up to the level of the tops of the blocks 25 and around the bellows assembly base block 27 and such substance 37 hardens about the blocks 25 and moulds thereinto the insulated lower end portions of the respective conductors 14b, 15b and 16b.
The bellows housing 28 includes a central member or body 38 having the lower end 39 thereof bored upwardly and externally threaded for connection into the aforesaid block 27, while a larger diameter portion thereabove is bored downwardly to a larger diameter, there being a communication port 40 provided through the partition wall thus resulting.
A bellows 41 of conventional design is provided with its upper end 42 connected, as by brazing, to the inner wall or surface of the housing body 38; the bellows extending downwardly and then recurved to extend upwardly, as best shown in FIG. 2. The inner upper part of the bellows 41 includes an annular part 43 to provide a shoulder and a cylindrical portion 44 having a closed upper end which extends upwardly centrally from the annular shoulder 43.
The upper end of the bellows housing body 38 has internal threads 45 therein to threadably receive the externally threaded lower end of the adjustment gland 46 which is counterbored so that the upper end of a spring 47 may seat therein, the lower end of the spring 47 bearing upon an annular disc 48 which is bored to receive the bellows upper end 44 therethrough while the disc 48 seats upon the bellows shoulder 43.
A closure plunger 50 extends slidably sealably through a bore 49 provided in the gland 46, the lower end of such plunger seating upon the closed upper end of the bellows inner cylindrical upper portion 44. A single pole, double throw switch 51 is indicated occupying the upper part of the space within the casing or assembly housing 11 and such switch 51 may include a bracket 52 supported by the bellows housing 38, or optionally, or additionally the casing 53 of the switch 51 may be located, and/or supported by screws 54 extending inwardly from the housing or casing 11.
The single pole, double throw switch 51, indicated in FIG. 2, is shown diagrammatically in FIG. 4 as including a post 56 from which extends a first conductor, as the insulated conductor 14b, also a switch arm 57 is indicated as being pivotally mounted on the post 56. Also, an upper post 58 and a lower post 59 are included to provide respective upper and lower contacts 60, 63, from which extend, respectively, the insulated conductors 15b, 16b.
The posts 56, 57 and 59 are shown in FIG. 2 as extending above the switch casing 53, and as having the respective insulated conductors 14b, 15b and 16!: extending therefrom, such conductors, as aforesaid, being shown lower in FIG. 2 as they enter the putty or hardenable material 37 of the base assembly 20.
A snap action plunger 61, indicated diagrammatically in FIG. 4, bears upwardly against the pivoted switch arm 57 and downwardly provides a point 62, also as shown in FIG. 2, which is contacted by the bellows actuated closure plunger 50, as will be hereinbelow described.
The upper member or conduit head 30 of the compressed gas conduit 17 has an externally threaded tubular valve 64 threadably received thereinto, such valve body providing a seat 65 therein, while a seating element 66 extends through the hollow valve 64 so that a head 67 at the upper end of the stem bears against the lower end face of the tube 29 thus to maintain the seating element 68 unseated under normal operative conditions, and until such time as the tube 29, comprising part of the assembly above the plug 12, may be removed, as for repair or disassembly. However, when such tube 29 is removed, the valve element 68 on the valve stem 66 may seat upwardly against the valve seat 65, and thus prevent escape of any compressed gas from the conduit 17.
The plurality of tubes or prongs 35 hereinabove described as extending downwardly from the plastic base 24 of the base assembly or bottom closure 20 are equally angularly spaced apart and equally radially distant from a central, vertical axis through the base, as best indicated in FIG. 3. Also, as shown in black in FIG. 3, only certain of these prongs 35 are used to have the conductor wires from the insulative conductors 14b, 15b, 16b, from the switch 51 thereabove, electrically connected thereinto, while the other tubes or prongs serve only as frictionally engaging connection members within the bores through the plug 12.
As indicated in FIG. 3, the prongs 35 are numbered consequently from No. 1 to No. 8 in a clockwise direction. For this reason an index tab 55 is shown in FIG. 3 extending radially inwardly into the metallic box bottom bore 23. This tab 55 may be used to orientate the relative positions of the numbered prongs in assembly, and as shown in FIG. 3 it is disposed between the prongs No. 1 and No. 8. correspondingly, as these prongs are inserted into the respectively numbered bores or receptacles in the plug 12, it may be known that prongs No. 2, No. 5 and No. 7, indicated in black in FIG. 3, are inserted in a proper plug bore 36 to carry electrical circuit to those respective tabs 14a, 15a and 16a which have been wired to connect with predetermined circuits, as from a negative and parallel positive sides of a source of electrical power.
In the form of invention shown in FIGS. 5-8, the construction of switch and upper part of bellows housing and parts assembled therein are shown to be essentially of the same construction as these elements are shown to be constructed in FIGS. 1-4. Differences enter in FIGS. 5-8 in that the compressed gas (air) inlet enters sidcwardly through the assembly case or housing to pass into a hollow connection means or fitting which communicates with the interior of the bellows housing. Thus the plastic or insulated base of the invention may be of simpler construction as it only receives therethrough the conductors from the switch, such conductors connecting into the metallic tubes carrying the metallic tabs of the plug.
In quick reiterative description, the pressure actuated switch and plug assembly 70 shown in FIGS. 5-8, includes an assembly case or housing 71 supported above a plug 72 with switch elements functioning correspondingly as those of the switch 50 shown in FIG. 1 of co-pending application Ser. No. 518,353 for Self-Purging Pneumatic Conveying Apparatus, filed J an. 3, 1966, and which issued Nov. 28, 1967, as Patent No. 3,355,221. A plate, wall or base 73 supports the plug 72 and insulated conductors 74b, 75b, 76b connect respectively with a negative source and two parallel positive source conductor lines.
The assembly housing 71 having bottom closure 80, includes a metallic box 81 which seats upon the plug 72, as shown in FIG. 6. A comparatively large central bore 83 is provided through the bottom of the metallic box 81, and a plastic or insulative base 84 seats within the box 81 which has a centrally disposed post or round depending member 89 to be manually pressed into a central bore 79 through the plug 72. Oppositely disposed connection blocks 85, indicated as of metal, are provided in slots in the periphery of a layer of hardenable, plastic like substance 97 comprising an insulative layer above the base flange 84, whereby machine screws 86 may be passed through the housing 71 and box 81 into the connection blocks 85 to effect assembly.
A hollow connection means including a metallic base block or fitting 87, as a T or similar fitting, is provided to seat centrally within the hardenable substance or plastic 97 at the time it is poured. The block or fitting 87 is bored and double counterbored with the upper or larger counterbore having internal threads 82 therein, threadably to receive the externally threaded lower end 99 of a hollow bellows housing 88. The base block or fitting 87 provides a sidcwardly extending, internally threaded bore 93 which communicates with the inner, lower bore 92 in the block or fitting 87, and which receives the inner part of a compressed gas inlet fitting 90 therein. From the fitting 90 a flexible tubing 91 extends to a conventional check valve 94 of the type with valve element spring urged seated in direction of the bellows housing base block 87; the check valve housing being rigidly assembled with, and sealably passing through the assembly case or housing 71. A quick disconnect fitting 125 connects a flexible tubing 77 to the outer end of the check valve housing 94 and extends to a terminal fitting 124 by which the tubing 77 is connected into a compressed gas or air manifold 78, as indicated substantially diagrammatically in FIGS. 5 and 6.
The plastic flange comprising an insulative base 84 'within the metallic box or bottom closure 81 of the assembly housing 71, has a plurality of equally, angularly spaced apart, metallic tubes or prongs 95 moulded thereinto, or tightly pressed thereinto, to extend downwardly through the central bore 83 through the metallic box 81, and therebelow to pass through correspondingly spaced, aligned bores 96 in the plug 72. Metallic conductor tabs 74a, 75a and 76a are shown in FIG. 6 as extending from below the plug 72 and upwardly connected into the plug 72 to establish electrical connections with the conductor wires of the insulated conductors 74b, 75b, 76b, respectively.
The suitable, hardenable substance 97, hereinabove described, that is poured upon the top of the flange 84 to harden around the lower part of the base block or hollow connection means 87, may be a material as Chico or a plastic, as epoxy. Such material 97, as confined within the housing 71, also hardens about, or receives therein, the lower ends of the aforesaid insulative conductors 74b, 75b and 75c, from which the conductor wires therefrom extend downwardly into the aforesaid prongs or sleeves 96.
The bellows housing 88 has an upper, cylindrical portion 98 and an externally threaded lower end 99 threadable into the internally threaded, outer counterbore 82, such lower end 99 having a passage 100 therethrough to communicate with the inner counterbore 100a of the connection member 87, the counterbore 100a in turn communicating with the central bore 92 in the connection member 87. A gland 106 having an externally threaded lower end is threadably received into the internally threaded upper end of the bellows housing 88, the lower face periphery of the gland 106 having the upper end 102 of the tubular bellows 101 connected therearound. Thus the bellows 101 extends downwardly from the gland 106 and is then recurved to extend upwardly with its inner upper end comprising an annular part 103 to provide a shoulder and a cylindrical portion 104 extending upwardly, centrally from the annular shoulder 103, the cylinder having a closed upper end, as shown in FIG. 6. The gland 106 is bored and counterbored from the lower end so that a spring 107 may seat upwardly within the counterbore and downwardly upon an annular disc or washer 108 which extends around the cylinder 104 and seats upon the upper face of the annular ring or shoulder 103. A closure plunger extends slidably, sealably through a central bore 109 provided through the gland 106 with the plunger 110 :being of length for the upper end to extend above the top of the gland 106 as the lower end thereof seats upon the closed upper end of the cylinder 104 which comprises the upstanding central part or core of the top closure 103, of recurved inner part of the bellows 101.
A single pole, double throw switch 111, in full correspondence with the switch 51 shown in FIGS. 2 and 4, ]includes a bracket 112 by which the switch 111 is mounted upon the upper portion of the cylindrical part 98 of the bellows housing 88, the casing 113 for the switch 111 being connected to the bracket 112 by screws 114.
As shown diagrammatically in FIG. 8, the switch arrangement is the same as that shown diagrammatically in FIG. 4. Thus the first conductor 74b extends from a switch post 116; the second conductor 75b extends from an upper switch post 118; and a third conductor 76b extends from a lower switch post 119. Also, a switch arm 117 is indicated as being pivotally mounted on the switch post 116; an upper contact is cantilevered from the upper switch post 118; and a lower contact 123 is cantilevered from the upper switch post 118; and a lower contact 123 is cantilevered from the lower switch post 119. As shown in FIG. 6, the posts 116, 118 and 119 extend above the switch casing 113, from whence the respective insulated conductors 74b, 75b and 76b extend, respectively, to the insulated conductors 74b, 75b and 76b, respectively, as they extend upwardly from the upper base element 97. Also, in FIG. 8, the snap action plunger 121 is indicated as hearing upwardly against the pivoted switch arm 117 and as downwarding providing a point 122, which is contacted by the bellows actuated closure plunger 110', correspondingly as the point 62 in FIG. 2 is contacted by the closure plunger 50.
As indicated in FIG. 7, the prongs 95 shown in FIG. 6 and the conductor wires therethrough are indicated by numbers l8, inclusive, while the prongs having the Wires for the insulated conductors 74b, 75b and 76b which figure in the switch action described in FIG. 8, also have the indicating circles filled for diagrammatical purposes, in black. In cases where only part of the conductor prongs or sleeves 95 are used, the other prongs 95 not having circuit wires therein, serve only as friction a1 members as they engage in the bores 96 in the plug 72.
correspondingly as indicated in FIG. 3, an index tab 115 is shown extending radially inwardly into the metallic box bore 83 for purposes of orientation between the numbered prongs 95 and plug bores 96. As indicated in FIG. 2, a spring 69 may be installed between the bottom inlet openings into the tubular valve 64 and the under side of the head of the seating element 68, to extend around the stem thereof below the head, thus to effect the range of adjustability.
The invention is not limited to specific combinations of assemblies of bellows housings with snap action, single pole, double throw switches, but rather includes various embodiments and modifications of assembled switches and control housings. Thus a considerable number of leads in excess of three may extend from the switch assembly, nor is the invention limited to a diaphragm or a bellows as the control means for transmitting gas pressure to operate switch opening and closing. Rather many various arrangements of switches and controls are considered which have a gas conduit means and conductor prongs extending from an assembly base to be guidahly insertable respectively into the gas conduit through a plug and into selected respective circuit conductor means from a source of electrical power.
As the invention stands, in synthesis, it includes various combinations of switches and actuating means therefor in assembly and adaptable for respective insertable as sembly with various combinations and variations of plugs supplied with electrical power and receiving gas conduit means thereto as long as such may fall within the broad spirit of the invention and within the broad scope of interpretation claimed for, and merited by, the appended claims.
What is claimed is:
1. A pressure actuated switch and plug assembly supporting therein a switch arm having a pivoted end, upper and lower, spaced apart contacts, and at least first, second and third conductors extending respectively from said pivoted end and from said contacts, and a snap action plunger having outwardly a contact point, a bellows housing having a bellows across the housing interior, a bored gland adjustably threadable downwardly into said bellows housing to bear upon a spring provided between said gland and said bellows, a closure plunger extending sealably through said gland bore, hollow connection means communicating with the interior of said bellows and providing a compressed gas inlet thereinto, an insulative base to receive the lower end of said hollow connection means therein, said conductors connecting with respective conductor prongs extending from said base, an insulative plug supported to connectably receive said prongs therein to contact respective predetermined circuit completing means extending therefrom, a compressed gas conduit connected into said compressed gas inlet above said base and extending from said inlet to a source of compressed gas, whereby said bellows moves upwardly and downwardly responsive respectively to increase and decrease of compressed gas pressure so that said closure plunger respectively contacts said point to urge said snap action plunger to pivot said arm to said upper contact to complete first and second conductor circuit, and said snap action plunger acts downwardly and pivots said arm to lower contact to complete first and third conductor circuit.
2. A pressure actuated switch and plug assembly as claimed in claim 1, in which said switch arm, contacts and snap action plunger are encased together, and which additionally comprises a housing including said base removably connected thereto, and which encloses the aforesaid switch element casing and said bellows housing, said conduit passing sidewardly through said housing above said base.
3. A pressure actuated switch and plug assembly as claimed in claim 1 in which a plurality of prongs including conductor prongs extend in circular arrangement from said base, and in which said base provides an indexing tab with relation to which the conductor prongs of said circle may be oriented thereby to connect with the circuit completing means extending from said plug.
4. A pressure actuated switch and plug assembly as claimed in claim 1 which includes in excess of two contacts and conductors therefrom with the contacts each closed and broken by movement of switch arm means.
5. A pressure actuated switch and plug assembly as claimed in claim 1 in which said base comprises lowermost a metallic box to seat on said plug and having a central bore through the bottom for extension of said prongs and said communication tube therethrough, said base being of plastic immediately above said bottom within said box and being comprised of a hardenable material uppermost around said hollow connection means and to mould around said conductors and around metal connection blocks through which said box is connected with an outer housing over said bellows housing and said switch parts and including said base and through which said conduit passes sidewardly above said base.
6. A pressure actuated switch and plug assembly as claimed in claim 1 in which said base is connected to said plug by a plurality of prongs including said conductor prongs, each comprising a metallic tube restrained in said base, with the wires of said conductors being soldered into selective prongs.
7. A pressure actuated switch and plug assembly as claimed in claim 1 in which said bellows extends downwardly from the wall of said bellows housing and is then recurved upwardly to provide a central upstanding projection on which seats said closure plunger.
8. A pressure actuated switch and plug assembly as claimed in claim 1 in which said assembly includes an outer housing for said switch parts and said bellows housing, and in which said switch parts are encased in a casing rigidly disposed with relation to said outer housing and said bellows housing, said conduit passing sidewardly through said housing above said base.
References Cited UNITED STATES PATENTS 2,411,796 11/1946 Leupold.
2,567,519 9/1951 Livingston 20083.91 2,768,646 10/1956 Plank.
2,716,395 8/1955 Pettigrew et a1.
ROBERT K. SCI-IAEFER, Primary Examiner ROBERT A. VANDERHYE, Assistant Examiner US. Cl. X.R. 337-320
US682960A 1967-11-14 1967-11-14 Pressure actuated switch and plug assembly Expired - Lifetime US3485976A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0464200A1 (en) * 1990-01-25 1992-01-08 Square D Company Pressure responsive switch

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2411796A (en) * 1945-01-01 1946-11-26 United Electric Controls Co Pressure actuated electrical switch
US2567519A (en) * 1948-02-27 1951-09-11 Livingston Ralph Pressure monitoring device
US2716395A (en) * 1951-08-22 1955-08-30 Hartford Special Machinery Co Fluid operated power apparatus and control mechanisms therefor
US2768646A (en) * 1953-01-12 1956-10-30 Shell Dev Pressure operated actuator for high-pressure service

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2411796A (en) * 1945-01-01 1946-11-26 United Electric Controls Co Pressure actuated electrical switch
US2567519A (en) * 1948-02-27 1951-09-11 Livingston Ralph Pressure monitoring device
US2716395A (en) * 1951-08-22 1955-08-30 Hartford Special Machinery Co Fluid operated power apparatus and control mechanisms therefor
US2768646A (en) * 1953-01-12 1956-10-30 Shell Dev Pressure operated actuator for high-pressure service

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0464200A1 (en) * 1990-01-25 1992-01-08 Square D Company Pressure responsive switch
EP0464200A4 (en) * 1990-01-25 1993-05-05 Square D Company Pressure responsive switch

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