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Publication numberUS2900791 A
Publication typeGrant
Publication dateAug 25, 1959
Filing dateFeb 17, 1958
Priority dateFeb 17, 1958
Publication numberUS 2900791 A, US 2900791A, US-A-2900791, US2900791 A, US2900791A
InventorsKinsey Jr John A
Original AssigneeKinsey Jr John A
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Automatic door or like closure operator
US 2900791 A
Abstract  available in
Images(3)
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Claims  available in
Description  (OCR text may contain errors)

25, 1959 .1. A. KINSEY, JR 2,900,799.

AUTOMATIC DOOR OR LIKE CLOSURE OPERATOR Filed Feb. 17, 1958 3 Sheets-Sheet 1 FiiG.i

INVENTOR.

JOHN A. KINSEY,IR.

ATTORNEY 5, 1959 .1. A. KINSEY, JR 2,900,791

AUTOMATIC DOOR OR LIKE CLOSURE OPERATOR Filed Feb. 17, 1958 3 Sheets-Sheet 2 INVENTOR. JOHN A. KINSEY, m

ATTORNEY Aug. 25, 1959 J. A. KINSEY, JR 7 2,900,791

AUTOMATIC DOOR OR LIKE CLOSURE OPERATOR Filed Feb. 17, 19.58 3 Sheets-Sheet 3 INVENTOR. JOHN A.KINSEY,IR. BY (4m;

ATTORNEY AUTOMATIC DOOR OR LIKE CLOSURE.

OPERATOR This invention relates to door operators, and in particular relates to a door or like closure operator of the type which is automatically operable as by stepping upon a mat.

Heretofore, automatic door operators of the character described have been generally unsatisfactory for certain reasons, such as that they have had too many working parts to become defective; or that they were large and cumbersome and, therefore, expensive to manufacture and unsightly to use; or that they were diflicult to maintain and to repair; or that they required special installation, such as by mounting the same in a recess provided in the floor, which often resulted in damage to the unit due to collection of moisture and dirt in the same.

One object of the present invention is to provide a simple, relatively small, automatic door operator of the character described, having a minimum of moving parts to wear out or to become defective or out of adjustment, and which, therefore, is relatively inexpensive to manufacture and to maintain.

Another object of the invention is to provide a compact door operator of the character described, which requires no elaborate mounting procedure, but which rather is easily mounted in a fixed position on a door frame or like structure and, therefore, which may be repaired in situ, or replaced, without materially interfering with normal use of the door, as by manual operation thereof.

Other objects of the invention will be manifest from the following brief description and the accompanying drawings.

Of the accompanying drawings:

Figure l is a horizontal cross-section through a portion of a door frame, illustrating a door closer of the invention attached thereto for opening and closing a door.

Figure 2 is a front elevation of Figure 1.

Figure 3 is an enlarged front view, partly broken away and in section, of the door closer shown in Figures 1 and 2.

Figure 4 is a horizontal cross-section, on the same scale, taken substantially on the line 44 of Figure 3.

Figure 5 is a schematic piping and wiring diagram, illustrating a system for automatic control of the operation of the door closer.

Figure 6 is a schematic piping and wiring diagram, similar to Figure 5, but illustrating a modified use of the invention for more fully automatic opening and closing of a door.

Referring particularly to Figures 1 and 2. of the drawings, the numeral 10 designates a door closer unit, including a housing 11 removably secured to a bracket 12, which in turn is suitably secured in the upper juncture of top and side structural elements 13 and 14 of a door frame 15 at the hinge side of a door 16. Extending from the centerof thehousingis a projecting end ofa rotatable shaft 17,=on which is. keyed a crank arm 18, on which a longitudinally adjustable link 19 is pivotally connected,

, States Patent 0 the other end of the link being pivotally connected to the upper portion of the door at 20. 'Ihe'arrangement' is such that turning the shaft 17 approximately 180 is operable to swing the door 16 open about Referring now to Figures 3 and 4 in particular, and Figures 1 and 2 in general, the housing 11 is formed with a cylindrical passage 22 therethrough, closed at opposite ends by removably threaded caps 23 and 24, and thereby defining a pressure fluid chamber 26. Reciprocably received within chamber 26 may be a plunger 27 including longitudinally spaced plunger heads or end portions 28 and 29, integrally connected to opposite ends of a toothed rack 30, said plunger heads having cylindrical peripheral surfaces in fluid-sealing sliding engagement with the cylindrical wall surface portions of the chamber 26. A fiat spiral wound spring 32, connected in known manner between shaft 17 and an upper extension 11a of the housing containing the spring, normally yieldingly retains the plunger 27 in the extreme left-hand position thereof, shown in full lines in Figures 3 and 4, through engagement of a pinion 33 with the rack 30.

Spaces 34 and 35 at opposite ends of the chamber 26, outwardly of the plunger ends, as well as a neutral compartment 36, defined between said plunger ends, are filled with pressure fluid, such as oil, which is at zero pressure when the unit is in the inoperative or door-closed condition of Figures 1 to 4. In this condition of the unit, loose ball valves 37 and 38 in the plunger heads 28 and 29, respectively, normally provide free passage of oil between chambers 34, 35 and 36.

For dampening shock at the end of opening and closing movements of plunger 27, suitably adjustable by-pass means 41 and 42 are provided in the housing at opposite ends of chamber 26. Each said bypass means includes spaced branch passages 43, '43 extending from the respective outer end of chamber 26 to an exhaust passage- Way 44 communicating with neutral compartment 36. The arrangement is such that when plunger 27 is urged from one end of the chamber to the other, the respective plunger head progressively covers the passages 43, thereby to build up dampening pressure in the respective chamber space 34 or 35.

The unit 10 may be hydraulically operated to open door 16 by selective provision of pressurized oil through a conduit 45, connected to cap 23, and including a springpressed ball or check valve 46 to the chamber space 34 (Figure 3). Application of'pressure in chamber space 34 is adapted simultaneously to urge plunger 27 to the right (Figures 3 and 4) and close ball valve 37, and at the same time closes ball valve 38 due to immediate increase of pressure in chamber space 35.

At this time the oil pressure in neutral chamber 36 Will remain substantially at zero, as any pressure fluid received from the by-pass means 41 and 42 is returned to the pumping system, to be described in greater detail later, through a return conduit 40.

To prevent loss or reduction of fluid pressure in chamber 34, through by-pass means 41, a conduit 47 may extend from the supply conduit 45 to a normally open cut-off valve 49, mounted in a housing 11 in association with passage 44 of by-pass valve 41. Cut-otf valve 49 includes a spring-pressed plunger which is yieldingly operable, by pressure fluid from conduit 47, to close the passage 44. Thus, the closing of valve 49 is simultaneous with door opening movement of plunger 27.

Operation of the door opening unit 10 of Figures 1 to 4 will be best understood by reference to the schematic diagram' of the operating and control system for the same shown in Figure 5. Accordingly, with .particularreference to Figure 5, when a person steps on a mat 49, in front of door 16, a switch S is closed across lines 11 and 12 to start a timer in a control box 50, and thereby through lines 1-3 and 1-4, connected to power lines L1 and L-2, to operate a motor M for a predtermined length of time.

Motor M drives a pump P, which circulates pressure fluid from a reservoir R, through a conduit 45a to the pump, through conduit 45 to open check valve 46, and through conduit 47-to close cut-off valve 49, return flow of the pressure fluid being through conduit 40 between compartment 36 and the reservoir. A blow-off check device 52 may be provided between conduit 45 and the reservoir.

The resultant application of fluid pressure within chamber portion 34 urges the plunger 27 to the right, as viewed in Figures 3 and 4, at which time the ball valves 37 and 38 are closed by increasing pressure in the opposite end chamber spaces 34 and 35. In the meantime, the cut-01f valve 49 will have been closed in the exhaust passage 44 of by-pass 41, and passages 43, 43, being exhaust branches of the same, are closed to exhaust of pressure fluid directly through exhaust passage 44 from the chamber portion 34 to the neutral compartment-'36. During the initial period of the power stroke, in which valve 49 is closed, a restricted flow of pressure fluid occurs around the plunger head 28, through the two branch passages 43, until the plunger head 28 first covers and then passes the innermost branch passage 43, such restricted flow being suflicient to reduce the pressure in chamber portion 34 and thereby obviate hammer action against the plunger head 28. After plunger head 28 passes the innermost exhaust branch 43, however, there can be no further exhausting or by-passing of pressure fluid from the chamber portion 43 to the neutral compartment 36, and full fluid pressure will be applied within chamber portion 34 for the remainder of the power stroke.

As the plunger moves toward the end of the power stroke to the right, trapped fluid in chamber portion 35 flows through both of the right hand branch passages 43, and the respective exhaust passage 44, until its innermost branch passage 43 is covered by plunger end 29, so that the trapped fluid has only restricted passage, through the outermost branch passage 43 and exhaust passage 44, whereby the speed of the plunger is reduced at the end of the power stroke.

Movement of the plunger to the right is operable through rack 30 and pinion 33, to turn shaft 17 against the action of wind-up spring 32, and to swing the arm 18 which through link 19 will open the door 16. After a preset time suflicient to permit passage of the aforementioned person through the doorway, the timer in control box 50 will shut off the motor M, which in turn will stop the pump and return the various valves to the original conditions thereof, shown in Figures 3 and 4, in which all pressure fluid within the chamber portions 34 and 35, and compartment 36, --will momentarily be at equalized pressures, and spring 32 will urge the plunger 27 from the chain-dotted position to the full line position thereof shown in Figure 4. As plunger 27 is moved to ward the left by the spring 32, however, cutoff valve 49 will have been spring-urged to the normally open position thereof, and ball-valves 37 and 38 will close and open, respectively, so that shock-absorbing pressure may be built up in chamber portion 34. As before, when the plunger moves toward the end of the spring-urged return stroke, to the left, the innermost branch passage 43 is closed for restricted passage of fluid through exhaust passage 44, valve 49 being open, thereby to reduce the speed of the plunger and prevent the door 16 from being slammed shut.

A switch S-1 at the opposite side of door-16 from switch S is operated by said person stepping upon a mat 46a to prevent premature further operation of switch S, such as by another person, before the first-named person is clear of the swinging door.

Figure 6 illustrates a schematic piping and wiring system for a modified use of the apparatus of Figures 1 to 4 4, wherein the door is closed, as well as opened, by fluidpressure.

For this purpose, however, the valves 46 and 49 are duplicated at the right-hand end of the housing, in conduit extensions 47a and 45b, respectively, from the source of pressure fluid supply. Like parts will be indicated hereafter by like numerals, unless otherwise noted.

Operation of the system shown in Figure 6 for opening or closing door 16 is substantially as described for opening the door in conection with Figure 5, except that operation of motor M by closing the door-opening switch S in addition, through timer means in control box 50, actuates a solenoid valve 53 in lines 15 and 16, to open the valve for a predetermined length of time to permit passage of pressure fluid to the plunger chamber portion 34. This actuates plunger 27 as before to open door 16. After said predetermined operation of the timer, it actuates a solenoid valve 54, in lines 17 and 1-8, to operate plunger 27 reversely, and thereby to close the door 16. In either case, the operation of switch S-1 renders switch S inoperative.

The double operating system is particularly desirable for opening and closing relatively large or heavy doors. In any event the spring 32 serves a purpose of yieldingly holding the door 16 fully closed when the system is in the inoperative condition shown in Figures 1 to 4.

Should certain automatic equipment fail or be in need of maintenance attention, the closer unit 10 may be oper ated manually, that is, by manually urging the door to open position and allowing the spring 32 to close it. To facilitate maintenance or repair work, or for convenience at initial installation of the equipment, the supply and return conduits 45 and 40 may be suitably connected through a manifold 55, secured to a fixed part of door frame 16.

Other modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims.

What is claimed is:

l. A door or like closure operating device, comprising a housing having therein axially spaced pressure-fluid containing chamber portions, a plunger having longitudinally opposite end portions in substantially fluid-sealing reciprocative relationship within respective said chamber portions, said housing having therein a pressure-fluid containing compartment closed off from said chamber portions by said plunger ends, means on said casing operable by reciprocation of said plunger and adapted to operate a door or the like, pressure-fluid by-pass means between opposite said chamber end portions and said compartment and adapted to be at least partially closed by movement of the respective said plunger ends toward the outer ends of the plunger strokes to increase the pressures in said chamber, portions and thereby to retard the speed of the plunger, a source of pressure fluid, control means operable to supply fluid under pressure from said source to at least one of said chamber portions to urge the plunger toward the opposite end, means for returning said plunger to said one end after said predetermined period, pressure-fluid return means being provided between said compartment and said source of pressure fluid, pressure-fluid conduit means provided from said supply' source to said by-pass means at said at least one end and having therein a cut-off valve including a spring-pressed member normally positioned to open the respective by-pass means to said compartment, and check valve means provided between said source of pressure fluid and said at least one chamber portion to prevent returnflow of pressure fluid therefrom which would otherwise close said cut-off valve means when said supply source is cut off, said member being yieldingly operable by pressure fluid supplied from said source by said control means in coordination with supply of fluid to said at least one chamber portion to close the respective said by-pass means to said compartment and thereby increase the eifective pressure in said at least one chamber portion.

2. A door or like closure operating device, comprising a housing having therein axially spaced pressure-fluid containing chamber portions, a plunger having longitudinally opposite end portions in fluid-sealing reciprocative relationship within respective said chamber portions, said housing having therein a pressure fluid containing compartment closed off from said chamber portions by said plunger ends, means on said casing operable by reciprocation of said plunger and adapted to operate a door or the like, pressure-fluid by-pass means between opposite said chamber end portions and said compartment and adapted to be "at least partially closed by movement of the respective said plunger ends toward the outer ends or the plunger strokes to increase the pressures in said chamber portions and thereby to retard the speed of the plunger, fluid-pressure operated valve means in each said plunger end portion and normally open to passage therethrough of pressure fluid between said chamber portions and said compartment, a source of pressure fluid, means operable to supply fluid under pressure to at least one of said chamber portions to urge the plunger toward the opposite end, the resultant increased pressures in both said chamber portions and against said plunger end portions thereby being operable to close both said valve means to check passage of fluid therefrom into said compartment, means for returning said plunger to said one end after said predetermined period, pressure fluidireturn means provided between said compartment and said source of pressure fluid, pressure fluid conduit means provided from said supply source to said by-pass means at said at least one end and having therein a cut-ofl valve means operable by pressure fluid supplied firom said source by said control means to close the respective said by-pass means to said compartment, and check valve means provided between said source of pressure fluid and said at least one end chamber portion and between said one end chamber portion and said by-pass means to prevent return flow of pressure fluid which would otherwise close said cut-olf valve means when said pressure fluid supply is cut off, means being provided to retard initial operation of said cut-off valve to reduce the effective pressure in said at least one chamber portion and thereby reduce the severity of initial hammer impact of pressure fluid upon the respective plunger end.

3. A door or like closure operating device, comprising a housing having therein axially spaced pressure-fluid containing chamber portions, a plunger having longitudinally opposite plunger end portions in fluid-sealing reciprocative relationship within respective said chamber portions, said housing having therein a pressure-fluid containing compartment separate from said chamber portions, means on said casing operable by reciprocation of said plunger and adapted to operate a door or the like, pressure-fluid by-pass means between each of the opposite said chamber portions and said compartment and adapted to be partially closed by movement of the respective said plunger ends toward the outer ends of the respective plunger strokes to retard the speed of the plunger in corresponding direction, a source of pressure fluid, fluid-pressure return means between said compartment and said source of pressure fluid, control means sequentially operable to supply fluid under pressure from said source first to one and then the other of said chamber portions to urge the plunger toward the opposite ends, and separate shut-ofi" valves in each said by-pass means and each operable by said application of fluid under pressure to the respective one or other of said chamber portions to close the portions of the respective said by-pass means not partially closed by therespective plunger and thereby to prevent 'by-passing of pressure fluid from said respective chamber portion to said compartment, check valve means provided to prevent return flow of pressure fluid from the respective said chamber,

portions when said supply source is cut oil from the same which would otherwise operate to close the corresponding said shut-off valve.

4. A device as set forth in claim 3, wherein said source of pressure fluid includes pump means, and wherein said control means includes a selectively initiated timer mechanism adapted to operate said pump for a predetermined length of. time during which said plunger is reciprocated toward said one end and back.

5. A device as set forth in claim 3, said control means including a reversing valve device having a first means which admits said fluid under pressure to said chamber portion at one end and a second means operable to admit said fluid under pressure to said opposite end chamber portion when said first means is inactivated.

6. A door or like closure operating device, comprising a housing having therein axially spaced pressure-fluid containing chamber portions, a plunger having longitudinally opposite end portions in fluid-sealing reciprocative relationship within respective said chamber portions, said housing having therein a pressure-fluid containing compartment closed off from said chamber portions, means on said housing operable by reciprocation of said plunger and adapted to operate -a door or the like, fluid-pressure operated valve means in each said plunger end portion and normally opento passage therethrough of pressurefluid between the chamber portions and said compartment, means for supplying fluid under pressure from a source thereof to at least one of said chamber portions to urge the plunger for a power stroke toward the opposite end, the resultant increased pressure in both said chamberportions and against said plunger end portions thereby being operable to close both said valve means to check passage of pressure-fluid into said compartment, means for returning said plunger to said one end after said power stroke, means for returning the pressure-fluid from said compartment to said source, exhaust passage means opening to said compartment and axially spaced branch passages from said at least one chamber portion to said exhaust passage means, cut-off valve means in said exhaust passage means, and means operable by supplying fluid under pressure to said at least one chamber for the power stroke to close said cut-01f valve means and prevent flow of fluid from the at least one chamber to said compartment through said spaced branch passage means and exhaust passage means, the spacing of said branch passage means being such that during an initial proportion of said power stroke a restricted flow of pressure-fluid occurs around the respective plunger end portion to reduce the effective pressure in the at least one chamber portion and thereby to reduce initial hammer impact against the plunger, movement of the plunger end portion beyond said predetermined extent thereby increasing the effective pres sure against the plunger.

7. A door or like closure operating device, comprising a housing having therein axially spaced pressure-fluid containing chamber portions, a plunger having longitudinally opposite end portions in fiuid sealing reciprocative relationship within respective said chamber portions, said housing having therein a pressure-fluid containing compartment closed off from said chamber portions, means on said housing operable by reciprocation of said plunger and adapted to operate a door or the like, fluid-pressure operated valve means in each said plunger end portion and normally open to passage therethrough of pressure fluid between the chamber portions and said compartment, control means operable to supply fluid under pressure from a source thereof to at least one of said chamber portions to urge the plunger for a power stroke toward the opposite end, the resultant increased pressure in both said chamber portions and against said plunger end portions thereby being operable to close both said valve means to check passage of pressure fluid into said compartment, means for, returning said plunger to said one end after said power stroke, means for returning the pressure-fluid from said compartment to said source, exhaust passage means opening to said compartment and axially spaced branch passages from said atleast .one chamber portion to said exhaust passage means, cut-off valve means in said exhaust passage means, and means operable by supplying fluid under pressure to said at least one chamber for the power stroke to close said cu t-ofi valve means and prevent flow of fluid fromthe at least one chamber to said compartment through said spaced branch passage means and exhaust passage means, the spacing of said branch passage means being such that during an initialproportion of said power stroke a restricted flow of pressure fluid occurs around the respective plunger end portion to reduce the effective .pressure in the at least one chamber portion and thereby to reduce initial hammer impact against the plunger, movement of the plunger end portion beyond said predetermined extent thereby increasing the effective pressure against the plunger, and check valve means provided between said source of pressure-fiuidand said at least one chamber portion to prevent return flow of pressure-fluid therefrom which would otherwise close said cut-off valve means when said source is cut off.

8. A door or like closure operating device, comprising a housing having therein axially spaced pressure-fluid containing chamber portions, a plunger having longitudinally opposite end portions in fluid-sealing reciprocative relationship within respective said chamber portions, said housing having therein a pressure-fluid containing compartment closed 01f from said chamber portions, means on said housing operable by reciprocationof said plunger and adapted to operate a door or thelike, fluidpressure operated valve means in each said plunger end portion and normally open to passage therethrough of pressure-fluid between the chamber portions and said compartment, a source of pressure-fluid, control means operable to supply fluid under pressure from said source to at least one of said chamber portions to urge the plunger for a power stroke toward the opposite end, the resultant increased pressure in both said chamber portions and against said plunger end portions thereby being operable to close both said valve means to check passage of pressure-fluid into said compartment, means for returning said plunger to said one end after said power stroke, pressurefluid return means provided between said compartment and said source of pressure-fluid, exhaust passage means opening to said compartment and axially spaced branch passages from said' at least one chamber portion to said exhaust passage means, cut-off valve means in said exhaust passage means, and means operable by supplying fluidunder pressure to said at least one chamber for the power stroke to close said cut-off valve means and prevent flow of fluid from the at least one chamber to said compartment through said spaced branch passage means and exhaust passage means, the spacing of said branch passage means being such that during an initial proportion of said power stroke a restricted flow of pressure-fluid occurs around the respective plunger end portion to reduce the effective pressure in the at least one chamber portion and thereby to reduce initial hammer impact against the plunger, movement of the plunger end portion beyond said predetermined extent thereby increasing the efiective pressure against the plunger, said control means including a delayed-action mechanism adapted to supply said fluid under pressure for a predetermined length of time before said means for returning said plunger is effective.

References Cited in the file of this patent UNITED STATES PATENTS 1,120,833 McElroy Dec. 15, 1914 1,306,966 Marcoux et al June 17, 1919 1,443,200 Adams Jan. 23, 1923 2,192,745 Hurd Mar. 5, 1940 2,276,338 Potter et a1 Mar. 17, 1942 2,292,336 Farnham Aug. 4, 1942 2,298,542 Potter et al. Oct. 13, 1942 2,578,894 Maurer Dec. 18, 1951 2,586,442 Seagren Feb. 19, 1952 2,735,404 Komph Feb. 21, 1956 2,758,835 Wikkerink Aug. 14, 1956 2,808,256 Landert Oct. 1, 1957

Patent Citations
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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3036712 *Nov 28, 1958May 29, 1962Charles S BarbaraPortable skim filter
US3043277 *Jul 20, 1960Jul 10, 1962Carlson MartinHydraulic door operator system and control means therefor
US3149536 *Mar 17, 1960Sep 22, 1964Horton Automatics IncAutomatic sliding panel operators
US3302330 *May 20, 1964Feb 7, 1967Stanley WorksAutomatic door operator
US3302331 *Aug 21, 1964Feb 7, 1967SturmDoor mechanism
US3407598 *Nov 9, 1966Oct 29, 1968Zentsu Denki Kabushiki KaishaHydraulically operated opening and closing device for doors or the like
US4222147 *Mar 20, 1978Sep 16, 1980Reading Door Closer Corp.Door closer with assist or door operating features
US4365442 *Sep 24, 1980Dec 28, 1982Speer Harold AAutomatic door control system
US4660324 *Aug 30, 1985Apr 28, 1987Nyenbrink Willard HDoor opener
US20140165329 *May 30, 2012Jun 19, 2014Dorma Gmbh Co.KgLinkage arm of a swivel-door-leaf actuator
Classifications
U.S. Classification60/394, 49/30, 91/35, 49/264
International ClassificationE05F15/00, E05F15/04
Cooperative ClassificationE05F15/04
European ClassificationE05F15/04