US3746802A

US3746802A - Pushbutton switch control assembly with flexible cord or equivalent allowing operation of one pushbutton and associated switch at a time

Info

Publication number: US3746802A
Application number: US00216065A
Authority: US
Inventors: F Sandi; T Schawinsky
Original assignee: Essex International Inc
Current assignee: Lear Corp EEDS and Interiors; ExxonMobil Oil Corp
Priority date: 1972-01-07
Filing date: 1972-01-07
Publication date: 1973-07-17
Anticipated expiration: 1990-07-17
Also published as: JPS512700B2; JPS4881236A; CA970012A; DE2300470C3; DE2300470B2; DE2300470A1

Abstract

A pushbutton control assembly for operating a vehicle''s heating, ventilating, and air conditioning system cmprises a housing having a movable valve for operating a plurality of fluid motors and electrical switch contacts for operating a plurality of electrical devices, the valve being adjustable by means of a single slide member the position of which is determined by a selected one of a number of reciprocable pushbuttons which also effect opening and closing of selected switch contacts. A flexible motion transmitting cord is coupled to all of the pushbuttons and is operable to effect movement of a selected pushbutton in one direction in response to movement of any other pushbutton in the opposite direction.

Description

United States Sandi et al.

Patent [191 Schawinsky, South Lyon, both of Mich.

Essex International, Inc., Fort Wayne, Ind.

Filed: Jan. 7, 1972 Appl. N0.: 216,065

Assignee:

U.S. Cl. 200/5 E, ZOO/50 C, 74/483 PB Int. Cl. H01h 9/26 Field of Search 200/5 E, 5 EA, 5 EB,

200/5 OC, 5 R; 74/483 PB 1 References Cited UNITED STATES PATENTS [451 July 17, 1973 2,320,774 6/1943 Flynt 200/5 EA 3,205,318 9/1965 Bilek 200/5 E 3,268,673 8/1966 Bilek 200/5 E 3,183,315 5/1965 Kiely 200/5 EB 1,370,304 8/1932 Wentzel 200/5 E X Primary Examiner-J. R. Scott Attorney-John F. Learman,.l0hn K. McCulloch et a1.

[57] ABSTRACT A pushbutton control assembly for operating a vehicles heating, ventilating, and air conditioning system cmprises a housing having a movable valve for operating a plurality of fluid motors and electrical switch contacts for operating a plurality of electrical devices, the valve being adjustable by means of a single slide member the position of which is determined by a selected one of a number of reciprocable pushbuttons which also effect opening and closing of selected switch contacts. A flexible motion transmitting cord is coupled to all of the pushbuttons and is operable to effect movement of a selected pushbutton in one direction in response to movement of any other pushbutton in the opposite direction.

PUSIIBUTTON SWITCII' CONTROL ASSEMBLY WITH FLEXIBLE CORD OR EQUIVALENT ALLOWING OPERATION OF ONE PUSHBUTTON AND ASSOCIATED SWITCI-I AT A TIME The invention disclosed herein relates to pushbutton operated apparatus especially adapted for controlling the operation of a vehicle s heating, ventilating, and air conditioning system of thekind having certain components operated-by fluid pressure and other components operated electrically. Operation of the fluid pressure components is controlled by a shiftable instrumentality and operation of the electrical components is controlled by the making and breaking of electrical circuits. Control apparatus constructed according to the invention includes a plurality of reciprocable pushbuttons which are operable to effect movements of the fluid pressure control instrumentality'and making and breaking of the electrical circuits.

Heating, air conditioning, and ventilating apparatus included in automotive vehicles conventionally have a plurality of air ducts provided with doors for controlling the flow of air through the ducts. The positions of such doors conventionally are controlled by fluid actuated devices which, in turn, are controlled by an adjustable instrumentality such as a valve interposed between the fluid actuated devices and a source of fluid. The flow of air through the ducts to the heater and air conditioner units also is regulatedby means of electrically operated, multiple-speed blowers, the operation of which are controlled by manually operated switches. The air conditioning unitconventionally includes an electrically operated, magnetic clutch for coupling and uncoupling the air conditioner compressor to and from the vehicle engine by means of manually operated switches.

A typical vehicle air conditioning, heating, and ventilatingsystem, together with its operating controls and ducts, is disclosed in US Pat. No. 2,914,629 granted Nov. 24, 1959, and to which reference may be had for a more detailed description of the system.

The control apparatus for the system disclosed inthe aforementioned patent functions satisfactorily, but includes a large number of'parts heretofore deemed essential to provide the necessary control'over the variouscomponents ofthe heating, ventilating, and air conditioning system. The'inclusion of a large number of parts increases the cost of such controlapparatus, not only because of the necessity of manufacturing such parts, but also because of the time required in their assembly. Moreover, the provision of alarge number of parts in 'a control device of the kind referred to requires the expenditure of considerable force to effect adjustmerit of the controlapparatus from one condition to another inasmuch as sufficient force must be applied to effect movement of all, or most, of such parts. The inclusion of multiple parts also increases the likelihood of failure of the control apparatus due to wear or imperfections in manufacture and assembly of such parts.

An object of this invention is to provide control apparatus for avehicles heating, ventilating, and air conditioning system and which overcomes the disadvantages of prior art apparatusfor similar purposes by substantially reducing the numberof parts required.

Another object of the invention is to provide control apparatus of the kind referred to having manually operable, reciprocable pushbuttons any one of which may be moved manually in one direction, and provided with improved means for returning such pushbutton to its original position in response to manual movement of any other pushbutton.

A further object of the invention is to provide a pushbutton control assembly of the character described and wherein each pushbutton is capable of operating both the fluid pressure and electrical components of a system.

Other objects and advantages of the invention will be pointed out specifically or will become apparent from the following description when it is considered in conjunction with the appended claims and the acompanying drawings, in which:

FIG. 1 is a longitudinal sectional view taken substantially along the line 1--1 of FIG. 2 and illustrating a pushbutton control device constructed in accordance with the invention and with the parts thereof in one position of adjustment;

FIG. 2 is a bottom plan view of the apparatus, with parts broken away for clarity of illustration;

FIG. 3 is a transverse sectional view taken on the line 3-3 of FIG. 1;

FIG. 4 is a view similar to FIG. 1, but illustrating the apparatus in a different position of adjustment;

FIG. 5 is a fragmentary view of a portion of the apparatus shown in FIG. 4 and illustrating the parts in another position of adjustment;

FIG. 6 is a view similar to FIG. 5, but illustrating the parts in still another position of adjustment; and

FIG. 7 is a plan view of electrical busses forming part of the apparatus.

A control device constructed in accordance with the invention comprises a casing or housing 1 composed of two

halves

2 and 3 formed of electrically insulating material such as nylon or the like and maintained in assembled relation by suitable means such as rivets, one of which is shown at 4a in FIG. 3. The casing half 2 has a base4 provided with a plurality of passages 5 comm unicating with an interior chamber 6, each of the passages also communicating with tubular fittings 7 carried by and projecting outwardly from the base 4. One of the fittings is adapted for connection toa pressure or vacuum fluid source and the others are adapted for connection to fluid motors of the kind capable of operating air duct doors or valves.

Slidably accommodated in the chamber 6 is a metal-- lic carrier 8 within which is received a rubber instrumentality or valve 9 having a plurality of passages 10 confronting the passages 5. A spring 11 reacts between able communication to be established among selected.

ones of the passages 5 to the exclusion of the others, depending upon the position of the valve 9 in the chamber 6.

A single slide member 12 is mounted in a recess 13 formed adjacent the side wall of the casing half 2 and comprises a body 14 formed of nylon or other suitable insulating material having a driving stud l5 fitted into an openingformedin the carrier 8 so as to couple the valve and the slide 12 for conjoint reciprocating movements along a path defined by the recess 13. The recess 13 has a bottom wall 16 on which the lower edge of the slide body 14 bears throughout its length. The upper or opposite edge of the slide body 14 has a plurality of spaced, generally V-shaped notches l7, 18, 19, 20, 21,

and 22 formed therein, the sides of the notches being contoured to form cams for a purpose subsequently to be explained.

The casing half 3 has a base 23 on the inner surface of which are mounted

electrical buses

24, 25, and 26. The bus 24 has three mounting

feet

27, 28 and 29 which are secured to the base 23 by

rivets

30, 31, and 32, respectively. The bus 25 has mounting

feet

33 and 34 secured to the base by

rivets

35 and 36, respectively, and the bus 26 has mounting

feet

37 and 38 secured to the base by

rivets

39 and 40, respectively. The bus 24 has six integral, resilient, electrically

conductive contact leaves

41, 42, 43, 44, 45, and 46, each of which has an undulating configuration in cross-section as is best shown in FIG. 3. The bus 25 has four contact leaves 47 50 which are similar to and confront the leaves 41 44, respectively. The bus 26 has a pair of

similar contact leaves

51 and 52 which confront the

leaves

45 and 46, respectively. The confronting leaves of each pair of contacts are spaced apart from one another, and the configuration of each leaf is such that, at the free ends of each pair of confronting leaves, is a constricted throat 53 (FIG. 3) leading to an enlarged chamber 54. The free ends of the contact leaves thus constitute detent means for a purpose presently to be explained.

The bus mounting foot 28 is connected by its rivet 31 to a terminal 55 which may be connected by wiring to the positive side of a battery (not shown). The mounting foot 34 of the bus 25 is connected by its rivet 36 to a terminal 56 and the foot 37 of the bus 26 is connected by its rivet 39 to a third terminal 57. The

terminals

56 and 57 may be connected to the negative side of the battery through high speed and low speed terminals, respectively, of an electric blower (not shown).

Normally, none of the pairs of contact leaves are in engagement so that each pair of contact leaves constitutes a normally open switch, but when the leaves of any pair of contacts are closed or bridged by a conductor, a circuit will be established through the terminal 55, and one of the

terminals

56 or 57.

A pair of

terminals

58 and 59 is mounted on the base 4 of the casing half 2 by means of

rivets

60 and 61 which also mount electrically

conductive spring arms

62 and 63 thatextend inwardly of the casing l and are provided with

contacts

64 and 65 at their free ends. Adjacent their free ends, the

arms

62 and 63 are bent to form

cam surfaces

66 and 67, respectively, for a purpose hereinafter to be explained. The contacts 64 and I 65 normally are disengaged, but may be moved into engagement to establish a circuit between the

terminals

58 and 59. These terminals may be connected to a magnetic clutch (not shown) of a conventional vehicle air conditioner compressor through a battery or other source of electrical energy.

The

casing halves

2 and 3 have

top walls

68 and 69, respectively, which are relieved at corresponding intervals to form six openings communicating with the interior of the casing. Slidably mounted in the openings are six

reciprocable pushbuttons

70, 71, 72, 73, 74, and 75. At the inner end of the pushbutton 70 is an extension 76 that is adapted to pass between the confronting contact leaves 41 and 47. The other pushbuttons 71 75 have similar extensions 77 81, respectively, which are adapted to pass between the confronting leaves of their associated contacts. Each of the extensions is pierced adjacent its free end for the accommodation of a double-headed, electrically conductive contact 82, but the contact 82 is omitted from the extension 76 so as to form an opening 82a (FIG. 4). However, each of the contact leaves 41 and 47 associated with the extension 76 is provided with an indentation or dimple 83 so positioned as to be capable of entering the opening 82a when the extension 76 is in the retracted position shown in FIG. 1.

Straddling each of the pushbuttons 70 75 are guide blocks 84 which guide the pushbuttons in their reciprocating movements.

The guide blocks 84 are formed integrally with the casing half 2.

The apparatus includes a flexible, non-elastic, motion transmitting cord 85 which extends alongside the push buttons 70 75 and rests against the guide members 84. The length of the cord 85 exceeds the distance spanned by the pushbuttons 70 75 and the excess length of the cord corresponds substantially to twice the travel of any of the pushbuttons. The opposite ends of the cord are clamped in anchor members 86 carried adjacent opposite ends of the casing 1.

Each of the pushbuttons 70 4 75 includes a laterally projecting coupling stud 87 which bears. against the cord 85 but on the opposite side thereof from the guides 84. Each pushbutton also carries a second stud 88 having a wedge-shaped shifter extension 89 which overlies the associated notches 17 22 formed in the slide body 14. The shifters 89 areso positioned as to be capable of engaging at least one edge of their associated notches.

The parts of the apparatus are illustrated in FIG. 1 in the positions they occupy when the heater, defroster, and air conditioner of a vehicle are inoperative and the fresh air vent is closed. In these positions of the parts, all pushbuttons occupy an outwardly projected position, except the pushbutton which may bear the notation OFF, and which is depressed or retracted into the casing 1 so that its extension 76 lies between the contact leaves 41 and 47 with the dimples 83 accommodated in the opening 82a. The dimples 83 and the opening thus constitute cooperable detents for releasably latching the pushbutton 70 in its retracted position.

In the retracted position of the pushbutton 70 the as sociated shifter 89 is at the bottom of the notch 17, thereby maintaining the slide 12 in the extreme' lefthand positionand preventing inadvertent movement of the slide 12 and the valve 9 from the positions shown in FIG. 1. In this position of the pushbutton 7.0a portion of the cord 85 is displaced inwardly of the casing by the associated stud 87 so as to take up the slack created by the excess length of the cord. The cord, therefore, is maintained taut and precludes inadvertent retraction or rattling of any of the other pushbuttons. The studs 87 cooperate with the casing wall 68 to limit outward movement of the pushbuttons.

If it is desired to operate the vehicles defroster the pushbutton 75, bearing the notation DEF" may be depressed and moved from the position shown in FIG. 1 to the position shown in FIG. 4. As the pushbutton is retracted, its stud 87 will bear against the cord to move the latter inwardly of the casing between the adjacent guides 84. The cord 85 thus will be stressed longitudinally causing it to exert a force on the pushbutton 70 to move the latter outwardly of the casing, thereby withdrawing the extension 76 from between the

contact blades

41 and 47 and withdrawing the shifter 89 from the notch 17. As the pushbutton 75 continuesto move inwardly of the casing its shifter 89 will engage a wall of the notch 22 and shift the slide 12 and the valve 9 to the right from the positions shown in FIG. 1 to the positions shown in FIG. 4. Those passages 5 associated with the doors of the ducts leading to the vehicles defroster thus will be manipulated so as to enable air to flow to the defroster outlets. Simultaneously with the shifting of the slide 12, the extension 81 of the pushbutton 75 will be introduced between the confronting

contact blades

46 and 52 thereby enabling the conductor 82 to bridge the contact blades and establish a circuit via the

terminals

55 and 57 to the defroster blower. The detenting action between the

contact blades

46 and 52 and the conductor 82 will maintain the pushbutton 75 in its retracted position and the engagement between the shifer 89 and the walls of the notch 22 will maintain the slide 12 and the valve 9 in their adjusted position.

Any one of the other pushbuttons 71 74 may be depressed in the same manner described in connection with the pushbutton 75. i

The

pushbuttons

71 and 72 control the vehicles air conditioning unit and may bear the notations MAX A/C" and A/C", respectively. Depression of the pushbutton 71 when the slide 12 is in the position shown in FIG. 1 establishes a circuit via the contact leaves 42 and 48 and the

terminals

58 and 59 to the blower, but the notch .18 is so contoured that the slide 12 is not shifted. Thus, the doors of the air ducts will remain in the same positions they occupy when the OFF pushbutton is depressed so as to enable the air within the vehicle to be circulated through the air conditioning unit without the introduction of fresh air. As the pushbutton 71 is depressed the stud 88 associated therewith engages the cam surface 66 on the contact leaf 62 and earns the latter toward the leaf 63 so as to engage the

contacts

64 and 65 as is shown in FIG. 5. A circuit thus may be completed through the

terminals

58 and 59 to the magnetic clutch of the air conditioner so as to operate the compressor.

If it is desired to permit fresh air to be circulated through the air conditioner, the A/C" pushbutton 72 may be depressed to complete a circuit via the contact leaves 43 and 49 to the blower and to cam the leaf 63 toward the leaf 62 so as to close the'contacts 64 and 65 and complete a'circuit to the magnetic clutch of the air conditioning unit. These are the positions of the parts shown in FIG. 6. As the pushbutton 72 is depressed, its shifter 89 will engage the wall of the notch 19 so as to shift the slide 12 to the right from the position shown in FIG. 1, thereby establishing communication between those passages 5 which enable a door in the air duct to be adjusted in such manner as to permit fresh air to enter the interior of the vehicle.

Depression of the VENT" pushbutton 73 will establish a circuit via the

contact blades

44 and 50 to the vehicle blower and will effect shifting of the slide 12 to a position in which fresh air may be admitted to the interior of the vehicle. When the VENT? pushbutton is depressed, the slide 12 occupies the same position that it occupies when the A/C" pushbutton 72 is depressed.

Depression of the HEAT" pushbutton 74 will establish a circuit to the blower via the

contact blades

45 and 5! and will shift the slide 12 to a position such that the passages 5 which control theair duct door control will locate the door in a position to direct airthrough the heater unit.

Regardless of which one of the several pushbuttons is depressed, its movement inwardly of the casing will cause corresponding simultaneous outward movement via the cord of any previously depressed pushbutton, and the configuration of the wallsof the notches in the slide are such that the slide may be shifted by the pushbutton being depressed without interference from the pushbutton being returned to its projected position. Since only one slide is required in control apparatus constructed in accordance with the invention, the max imum force which must be applied to any pushbutton to depress does not exceed that necessary to shift the single slide, the valve, spread the contact leaves associated with the pushbutton, and restore the previously depressed pushbutton.

The disclosed embodiment is representative of a presently preferred form of the invention, but is intended to be illustrative rather than definitive thereof, The invention is defined in the claims.

We claim:

1. Pushbutton control apparatus comprising valve means movable between a plurality of positions; a slide member mounted for back and forth movements along a path; means coupling said slide member to said'valve means for moving the latter in response to movements of said slide member; a plurality of pushbuttons mounted for back and forth movements along a path lateral of the path of movement of said slide member; cooperable means on said slide member and on each of said pushbuttons engageable in response to movement in one direction of a selected one of said pushbuttons to effect movement in a selected direction of said slide member; means flexible in the path of movement of and spanning said pushbuttons and having a length greater than the distance spanned by said pushbuttons; and means coupling said flexible means to each of said pushbuttons operable in response to movement in said one direction of any other one of said pushbuttons to impart movement of said selected one of said pushbuttons in the opposite direction to disengage the cooperable means on said slide member and said selected one of said pushbuttons. I

2. Apparatus according to claim 1 wherein said flexible means comprises a cord.

3. Apparatus according to claim 1 wherein the excess length of said flexible means corresponds substantially to twice the length of travel of a pushbutton.

4. Apparatus according to claim 1 including guide means straddling each of said pushbuttons and engaging said flexible means, said coupling means including a part carried by each of said pushbuttons for engagement with said flexible means between adjacent guide means.

5. Apparatus according to claim 4 wherein said flexible means extends alongside all of said pushbuttons and wherein said part comprises a projection extending from and overlying said flexible means.

6. Apparatus according to claim 1 wherein said cooperable means comprises a cam surface on said slide member in the path of movement of and engageable by said selected one of said pushbuttons.

7. Apparatus according to claim 6, wherein said slide member has a cam surface in the path of movement and engageable by each of said pushbuttons, said cam surfaces being so contoured that the engagement between a selected one of said cam surfaces and the associated pushbutton effects predetermined movement of said slide member.

8. Apparatus according to claim 1 including normally open electrical switch contacts mounted in the path of movement in one direction of at least one of said pushbuttons; and means carried by said one pushbutton for closing said contacts.

9. Apparatus according to claim 8 wherein at least one of said switch contacts and said one pushbutton have cooperable detent means for releasably latching said one pushbutton in contact closing relation.

10. Apparatus according to claim 8 including an additional pair of normally open contacts, and nonconductive detent means carried by another of said push-.

buttons engageable with the contacts of said additional pair for latching said another pushbutton.

11. Pushbutton control apparatus comprising valve means movable between a plurality of positions; a slide member mounted for back and forth movements along a path; means coupling said slide member to said valve means for moving the latter in response to movements of said slide member; a plurality of reciprocable push buttons mounted for back and forth movements along a path lateral of the path of movement of said slide member; cooperable means on said slide member and on each of said pushbuttons for imparting movement to said slide member in a selected direction along its path in response to movement in one direction of any selected one of said pushbuttons; and means independent of said slide member and movable in the direction of movement of said pushbuttons for moving said selected one pushbutton in the opposite direction when another one of said pushbuttons is moved in said one direction.

12. Apparatus according to claim 11 wherein the cooperable means on said slide member and said pushbuttons are so located that movement of said slide member from one position to another in response to said movement of said selected one of said pushbuttons conditions the cooperable means on said slide member and another of said pushbuttons to impart movement to said slide member in response to movement in one direction of said another pushbutton.

13. Apparatus according toclaim 11 including normally open switch contacts engageable and closable by at least one of said pushbuttons in response to movement thereof in said one direction.

14. Apparatus according to claim 13 including cooperable detent means on said switch contacts and said one pushbutton for releasably latching the latter in contact closing relation. v a

15. Apparatus according to claim 11 including motion transmitting means, and means coupling said motion transmitting means to all of said pushbuttons for moving said one pushbutton in the opposite direction in response to movement in said one direction ofany other pushbutton.

l6.Apparatus according to claim 15 wherein said' motion transmitting means comprises a flexible cord spanning all of said pushbuttons and having a length in excess of the distance spanned by said pushbuttons.

17. Apparatus according to claim 16 wherein said cord extends alongside each of said pushbuttons and wherein said coupling means comprises a part carried by each of said pushbuttons and engaging said cord.

18. Apparatus according to claim 17 including guide means straddling each of said pushbuttons and engaging said cord.

19. Pushbutton control apparatus comprising valve means movable between a plurality of positions; a single slide member mounted for back and forth movements along a path; means coupling said slide member to said valve member for moving the latter in response to movements of said slide member; a plurality of reciprocable pushbuttons each mounted for back and forth movements between first and second positions along a path lateral of the path of movement of said slide member; and cooperable cam means on said slide member and on each of said pushbuttons, the cam means on a selected one of said pushbuttons being engageable with the cam means on said slide member in response to movement of said one pushbutton in one i direction along its path from its first position to its second position and being operable to effect movement of said slide member along its path from a first position to another position, the cam means on another of said pushbuttons being engageable with the cam means on said slide member in response to movement of said another pushbutton in said one direction along its path from its first position to its second position and being operable to effect movement of said slide member along its path from said second position, the cam means on said slide member being operable to effect movement of said one pushbutton in the opposite direction along its path toward its first position in response to movement of said slide member from said second position.

20. Apparatus according to claim 19 including switch means and switch operating means carried by selected ones of said pushbuttons for operating said switch means in response to movements of said selected ones of said pushbuttons between said first and second positions. a

21. Apparatus according to claim 20 including cooperable detent means on said switch means and'said switch operating means for'releasably latching any of said selected ones of said pushbuttons in one of its said positions.

Claims

1. Pushbutton control apparatus comprising valve means movable between a plurality of positions; a slide member mounted for back and forth movements along a path; means coupling said slide member to said valve means for moving the latter in response to movements of said slide member; a plurality of pushbuttons mounted for back and forth movements along a path lateral of the path of movement of said slide member; cooperable means on said slide member and on each of said pushbuttons engageable in response to movement in one direction of a selected one of said pushbuttons to effect movement in a selected direction of said slide member; means flexible in the path of movement of and spanning said pushbuttons and having a length greater than the distance spanned by said pushbuttons; and means coupling said flexible means to each of said pushbuttons operable in response to movement in said one direction of any other one of said pushbuttons to impart movement of said selected one of said pushbuttons in the opposite direction to disengage the cooperable means on said slide member and said selected one of said pushbuttons.

2. Apparatus according to claim 1 wherein said flexible means comprises a cord.

10. Apparatus according to claim 8 including an additional pair of normally open contacts, and nonconductive detent means carried by another of said pushbuttons engageable with the contacts of said additional pair for latching said another pushbutton.

11. Pushbutton control apparatus comprising valve means movable between a plurality of positions; a slide member mounted for back and forth movements along a path; means coupling said slide member to said valve means for moving the latter in response to movements of said slide member; a plurality of reciprocable pushbuttons mounted for back and forth movements along a path lateral of the path of movement of said slide member; cooperable means on said slide member and on each of said pushbuttons for imparting movement to said slide member in a selected direction along its path in response to movement in one direction of any selected one of said pushbuttons; and means independent of said slide member and movable in the direction of movement of said pushbuttons for moving said selected one pushbutton in the opposite direction when another one of said pushbuttons is moved in said one direction.

13. Apparatus according to claim 11 including normally open switch contacts engageable and closable by at least one of said pushbuttons in response to movement thereof in said one direction.

14. Apparatus according to claim 13 including cooperable detent means on said switch contacts and said one pushbutton for releasably latching the latter in contact closing relation.

15. Apparatus according to claim 11 including motion transmitting means, and means coupling said motion transmitting means to all of said pushbuttons for moving said one pushbutton in the opposite direction in response to movement in said one direction of any other pushbutton.

16. Apparatus according to claim 15 wherein said motion transmitting means comprises a flexible cord spanning all of said pushbuttons and having a length in excess of the distance spanned by said pushbuttons.

19. Pushbutton control apparatus comprising valve means movable between a plurality of positions; a single slide member mounted for back and forth movements along a path; means coupling said slide member to said valve member for moving the latter in response to movements of said slide member; a plurality of reciprocable pushbuttons each mounted for back and forth movements between first and second positions along a path lateral of the path of movement of said slide member; and cooperable cam means on said slide member and on each of said pushbuttons, the cam means on a selected one of said pushbuttons being engageable with the cam means on said slide member in response to movement of said one pushbutton in one direction along its path from its first position to its second position and being operable to effect movement of said slide member along its path from a first position to another position, the cam means on another of said pushbuttons being engageable with the cam means on said slide member in response to movement of said another pushbutton in said one direction along its path from its first position to its second position and being operable to effect movement of said slide member along its path from said second position, the cam means on said slide member being operable to effect movement of said one pushbutton in the opposite direction along its path toward its first position in response to movement of said slide member from said second position.

20. Apparatus according to claim 19 including switch means and switch operating means carried by selected ones of said pushbuttons for operating said switch means in response to movements of said selected ones of said pushbuttons between said first and second positions.

21. Apparatus according to claim 20 including cooperable detent means on said switch means and said switch operating means for releasably latching any of said selected ones of said pushbuttons in one of its said positions.