US3655927A - Inlet valve and switch for central vacuum cleaner - Google Patents

Inlet valve and switch for central vacuum cleaner Download PDF

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Publication number
US3655927A
US3655927A US28649A US3655927DA US3655927A US 3655927 A US3655927 A US 3655927A US 28649 A US28649 A US 28649A US 3655927D A US3655927D A US 3655927DA US 3655927 A US3655927 A US 3655927A
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United States
Prior art keywords
cover plate
tube end
sockets
rod
tube
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
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US28649A
Inventor
Bruce E Samuelson
Robert A Dunst
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Whirlpool Corp
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Whirlpool Corp
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Publication of US3655927A publication Critical patent/US3655927A/en
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H3/00Mechanisms for operating contacts
    • H01H3/02Operating parts, i.e. for operating driving mechanism by a mechanical force external to the switch
    • H01H3/16Operating parts, i.e. for operating driving mechanism by a mechanical force external to the switch adapted for actuation at a limit or other predetermined position in the path of a body, the relative movement of switch and body being primarily for a purpose other than the actuation of the switch, e.g. for a door switch, a limit switch, a floor-levelling switch of a lift
    • H01H3/161Operating parts, i.e. for operating driving mechanism by a mechanical force external to the switch adapted for actuation at a limit or other predetermined position in the path of a body, the relative movement of switch and body being primarily for a purpose other than the actuation of the switch, e.g. for a door switch, a limit switch, a floor-levelling switch of a lift for actuation by moving a closing member, e.g. door, cover or lid
    • H01H3/162Operating parts, i.e. for operating driving mechanism by a mechanical force external to the switch adapted for actuation at a limit or other predetermined position in the path of a body, the relative movement of switch and body being primarily for a purpose other than the actuation of the switch, e.g. for a door switch, a limit switch, a floor-levelling switch of a lift for actuation by moving a closing member, e.g. door, cover or lid associated with a hinge of the closing member
    • AHUMAN NECESSITIES
    • A47FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47LDOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
    • A47L5/00Structural features of suction cleaners
    • A47L5/12Structural features of suction cleaners with power-driven air-pumps or air-compressors, e.g. driven by motor vehicle engine vacuum
    • A47L5/22Structural features of suction cleaners with power-driven air-pumps or air-compressors, e.g. driven by motor vehicle engine vacuum with rotary fans
    • A47L5/38Built-in suction cleaner installations, i.e. with fixed tube system to which, at different stations, hoses can be connected

Abstract

An inlet valve and switch device for a central vacuum cleaner system having a suction tube with an exposed inlet end and a cover plate for the tube inlet end that can be opened to expose the tube for connecting a cleaning device to it in which the opening movement of the cover plate closes the switch that energizes the central vacuum cleaner. The closing of the cover plate against the inlet end of the tube opens the switch to deenergize the central vacuum cleaner.

Description

United States Patent Samuelson et al.
lnventors:
Assignee:
Filed:
Appl. No.:
US. Cl lnt.Cl.
Bruce E. Samuelson, St. Paul; Robert A. Dunst, White Bear Lake, both of Minn.
Whirlpool Corporation Apr. 15, 1970 ..H0lh 3/16 Field oiSearch ..200/61.6; 15/314; 339/15;
References Cited UNITED STATES PATENTS Boryfewycz ..200/61 .6 I
[is] 3,655,927 [4 1 Apr. 11, 1972 3,291,927 12/1966 Riley, Jr. et a1 ..200/61.6 3,483,503 12/1969 Paradiso ..200/61.6 KR 3,283,093 1 1/1966 Bishop ..200/61.6 2,877,313 3/1959 Stoicos ..200/6l.6
Primary Examiner-H. 0. Jones Attorney-Hofgren, Wegner, Allen, Stellman & McCord 57] ABSTRACT 6 Claims, 6 Drawing Figures 270 & 2' 2o Patented April 11, 1972 FIGI FIGZ
INVENTORS. BRUCE E. SAMUELSON ROBERT A. DUNST fl l g a ww, j/ww ti'fiuw BY B m m N\.\\\ \sm Z A FIG4 ATTORNEYS.
INLET VALVE AND SWITCH FOR CENTRAL VACUUM CLEANER One of the features of this invention is to provide an inlet valve and switch device for a central vacuum cleaner system with the device including an improved movable cover plate and switch operating structure in order that as soon as the cover plate is moved to expose the inlet end of a suction tube an electric switch is closed to energize the system and as soon as the cover plate is moved to again close the inlet end of the tube the switch is opened to de-energize the system.
Another feature of the invention is the provision of an inlet valve and switch device having a movable cover plate mounted on a base member with improved hinge means arranged so that the cover plate is self-aligning during arcuate movement of the cover plate. This facilitates the sealing of the suction tube opening through a range of decreasing vacuum as the motor is coasting to a stop.
1 Still another feature of the invention is the provision of improved switch means for resiliently urging the cover plate to a closed position.
Other features and advantages of the invention will be apparent from the following description of one embodiment thereof as shown in the accompanying drawings. Of the drawings:
FIG. 1 is a rear elevational view of an inlet valve and switch device embodying the invention.
FIG. 2 is an enlarged fragmentary vertical sectional view taken substantially along line 2-2 of FIG. 1 and including a portion of a surrounding wall structure to illustrate the mounting of the device.
FIG. 3 is a sectional view taken substantially along line 3-3 of FIG. 1.
FIG. 4 is a fragmentary sectional view similar to the upper portion of FIG. 2 but illustrating the parts moved to switch closing position.
FIG. 5 is a fragmentary elevational view of the base member for the device showing details of the hinge structure.
FIG. 6 is an elevational view of a switch member illustrating a formed portion thereof for urging the cover plate to a closed position.
The inlet valve and switch device of this invention is employed in conjunction with a central vacuum cleaner system and serves to open and close the inlet end of a suction tube leading to a remote suction unit and at the same time to close and open a switch controlling the supply of electricity to the suction unit. Such a central or built-in vacuum cleaner is disclosed in Congdon U.S. Pat. No. 3,173,164 assigned to the same assignee as is the present application.
The valve and switch device shown in the accompanying drawings comprises a base member 10 made of a molded rigid plastic and having integrally formed therewith the inlet end 11 of a suction tube that is connected to a central suction unit (not shown) for establishing a vacuum therein. The ribbed inner surface of this base member 10 is shown in elevation in FIG. 1. As can be seen there, the base member surrounds the inlet end 11 which is substantially centrally located with respect to the device 12.
The base member 10 is attached to a wall section 13 containing an opening 14 through which the tube inlet end 11 is located. The base member 10 is attached to this wall by means of a clamp plate 40 and a clamp plate 15. The clamp plate 40 is positioned on the near side of the wall from the base member by a pair of screws 16 which extend through a pair of screw openings in plate 10 and engage the clamp plate 40, and the clamp plate is positioned on the opposite side of the wall from the base member 10. Clamp plate 40 and clamp plate 15 are clamped to the wall 13 by means of a pair of screws (not shown) which extend through a pair of screw openings in the plate 40 and engage the clamp plate 15.
integrally formed with the base member plate at the top thereof are a pair of horizontally aligned side receiving slots or sockets 18 that being made of the same molded plastic material as the base 10 are springy to define a relatively narrow entrance end 18a on the rear edge of the flange 19 that forms the border of the base member 10. These sockets 18 being located adjacent the upper end of the member 10 are of course above the inlet tube end 11. Normally covering the tube inlet end 11 at its outer surface 20 is a cover plate 21 also preferably made of a molded rigid plastic material. This cover plate 21 has integrally formed therewith adjacent its upper end a transverse hinge rod 22 of circular cross section. This rod is received in the sockets 18 by being forcibly pressed therein through the narrow entrance end 18a to distort the springy sides outwardly to permit the rod 22 to pass substantially to the innermost ends 23 of the sockets with the result that the rod 22 is retained in position yet is free to move arcuately with the cover plate 21 as it is moved from the closed position of FIG. 2 toward an outward extending open position as illustrated in FIG. 4.
Another feature of the disclosed invention is the provision of a self-aligning hinge structure for the cover plate. To this end the slots or sockets 18 are somewhat elongated along a horizontal axis at the innermost ends 23 of the sockets (see FIG. 5), which permits limited movement of the hinge rod 22 allowing it to float. This enables the cover plate 21 and gasket 38 to effect a seal with inlet tube 11 throughout the range of decreasing vacuum as the motor of the central vacuum cleaner system is coasting to a stop. This structure substantially prevents audible sounds from occurring at the system inlet valve after the vacuum cleaner is shut off.
The cover plate 21 is suspended from the base member sockets 18 when at rest but is free to move to open position as described above. Mounted on the interior of the cover plate 21 adjacent the hinge rod 22 is a normally open cleaner energizing electric switch 24 that comprises a pair of metal arms 25 and 26 which serve as electrical contacts. These arms may be made of copper or similar electrical conducting metal and both are mounted on a post 27 in spaced apart relationship by a single mounting screw 28. This mounting post 27 is also integral with the base member 10 and serves as a mounting for both of the contact arms 25 and 26 and also to insulate them from each other in conjunction with a rectangular insulator 27a which is mounted on post 27 between arms 25 and 26. One arm 25 has a raised contact point 29 for engaging the other arm 26 when it is desired to energize the system.
Formed integrally with the hinge rod 22 is a cam 30 that has an arcuate surface 31 for engaging the switch arm 26 when the cover plate 21 is rotated toward open position as shown in FIG. 4 and pressing switch arm 26 against the raised contact area 29 on the other switch arm 25. This energizes the electrically operated suction unit (not shown) by electricity supplied through conventional lead members connected to the two ends 32 and 33 of the switch arms 25 and 26, respectively.
Referring now to FIG. 6, a further feature of the invention is the provision of means to urge the cover plate 21 to closed position comprising a preforming of metal switch arm 26 as indicated at 26a in FIG. 6 so that the switch arm bears against the cam surface 31 as shown in FIG. 2. This acts as a return spring and lightly holds the cover plate 21 in a closed position by applying torque to the top surface of the cam thereby resiliently urging cover plate 21 to a closed position.
The cover plate 21 in addition to opening and closing the switch 24, as described, also operates as a valve to seal and unseal the inlet tube 11 at its outer surface 20. In order to pro vide this valve action the inner surface of the cover plate 21 is provided with an inwardly projecting integral post 34 that retains a circular lock nut 35 having a pair of oppositely located spring arms 36 that engage the post, as shown, to retain a circular washer 37 against a flexible rubber gasket 38. It is approximately the same diameter as the outer diameter of the tube outer surface 20. This assembly holds the gasket 38 against a circular flange 39 on the inner surface of the cover plate 21.
As can be seen from the above description, the arcuately movable cover plate which at rest is suspended over the inlet tube 11 provides an inlet valve seal for the tube and a switch device for energizing the central vacuum cleaner system when the suction tube is exposed. All of the parts except the attaching screw and the metal switch arms are preferably made of a molded plastic material which is also of course electrically insulating. In addition, the cover plate 21 and its integral hinge rod 22 and cam 30 are mounted on the base member plate solely by the resiliency and shaping of the parts without requiring additional fastening devices. Thus the device of this invention is kept very simple in construction, is sturdy and is capable of operating for long periods of time without trouble.
Having described our invention as related to the embodiment disclosed in the accompanying drawings, it is our intention that the invention be not limited by any of the details of description, unless otherwise specified.
The embodiment of the invention in which an exclusive property or privilege is claimed are defined as follows:
1. An inlet valve and switch device for a motor driven central vacuum cleaner, comprising: a suction tube having an exposed inlet end; a base member surrounding said tube at said tube end; means on said base member for providing a pair of spaced coaxial receiving sockets each with springy sides defining a narrow open entrance end, said sockets being located above said tube end; a cover plate for said tube end; a transverse hinge rod having opposite end portions integrally connected to said cover plate received in said sockets through said entrance ends by distortion of said sides, the cover plate thereupon being suspended by said sockets across said tube end for arcuate movement relative to said sockets across said tube end for arcuate movement relative to said sockets; a sealing member on the inner surface of said cover plate that is adjacent said tube end extending across said tube end when said cover plate is thusly suspended; a cleaner energizing electric switch mounted on said base member adjacent said rod; and
cam means on said rod for engaging and operating said switch on movement of said cover plate outwardly about said sockets to expose said tube end.
2. The device of claim 1 wherein said tube end, base member and said means providing said sockets are all integral parts of a single molded plastic member.
said hinge means for sealing said tube end with said cover plate sealing member throughout a range of decreasing vacuum as the vacuum cleaner motor is coming to a stop.
4. The device of claim 4 wherein said means on said hinge means for sealing comprises means forming a horizontal elongation of each of said sockets for permitting horizontal movement of said rod in said sockets.
5. The device of claim 1 wherein said cover plate, cam means, and hinge rod are integral parts of a single molded plastic member.
6. An inlet valve and switch device for a central vacuum cleaner, comprising: a suction tube having a exposed inlet end; a base member surrounding said tube at said inlet end; means on said base member for providing a pair of spaced coaxial receiving sockets each with springy sides defining a narrow open entrance end, said socket means being located above said tube end, said tube end, socket means and base member being integral parts of a single molded plastic member; a cover plate for said tube end carrying adjacent its upper end a transverse hinge rod received in said socket means through said entrance ends by distortion of said sides, the cover plate thereupon being suspended by said socket means across said tube end for arcuate movement relative to said socket means and said cover plate and rod are integral parts of a single molded plastic member; a sealing member on the inner surface of said cover plate that is adjacent said tube end extending across said tube end when said cover plate is thusly suspended; a normally open cleaner energizing electric switch mounted on said base member adjacent said rod comprising a pair of resilient contact anns held in position on said base member by a single attaching screw engaging said base member; and cam means integral with said rod for engaging and closing said switch on movement of said cover plate outwardly about said socket

Claims (6)

1. An inlet valve and switch device for a motor driven central vacuum cleaner, comprising: a suction tube having an exposed inlet end; a base member surrounding said tube at said tube end; means on said base member for providing a pair of spaced coaxial receiving sockets each with springy sides defining a narrow open entrance end, said sockets being located above said tube end; a cover plate for said tube end; a transverse hinge rod having opposite end portions integrally connected to said cover plate received in said sockets through said entrance ends by distortion of said sides, the cover plate thereupon being suspended by said sockets across said tube end for arcuate movement relative to said sockets across said tube end for arcuate movement relative to said sockets; a sealing member on the inner surface of said cover plate that is adjacent said tube end extending across said tube end when said cover plate is thusly suspended; a cleaner energizing electric switch mounted on said base member adjacent said rod; and cam means on said rod for engaging and operating said switch on movement of said cover plate outwardly about said sockets to expose said tube end.
2. The device of claim 1 wherein said tube end, base member and said means providing said sockets are all integral parts of a single molded plastic member.
3. The device of claim 1 wherein said sockets and rod comprise hinge means, and there are further provided means on said hinge means for sealing said tube end with said cover plate sealing member throughout a range of decreasing vacuum as the vacuum cleaner motor is coming to a stop.
4. The device of claiM 4 wherein said means on said hinge means for sealing comprises means forming a horizontal elongation of each of said sockets for permitting horizontal movement of said rod in said sockets.
5. The device of claim 1 wherein said cover plate, cam means, and hinge rod are integral parts of a single molded plastic member.
6. An inlet valve and switch device for a central vacuum cleaner, comprising: a suction tube having a exposed inlet end; a base member surrounding said tube at said inlet end; means on said base member for providing a pair of spaced coaxial receiving sockets each with springy sides defining a narrow open entrance end, said socket means being located above said tube end, said tube end, socket means and base member being integral parts of a single molded plastic member; a cover plate for said tube end carrying adjacent its upper end a transverse hinge rod received in said socket means through said entrance ends by distortion of said sides, the cover plate thereupon being suspended by said socket means across said tube end for arcuate movement relative to said socket means and said cover plate and rod are integral parts of a single molded plastic member; a sealing member on the inner surface of said cover plate that is adjacent said tube end extending across said tube end when said cover plate is thusly suspended; a normally open cleaner energizing electric switch mounted on said base member adjacent said rod comprising a pair of resilient contact arms held in position on said base member by a single attaching screw engaging said base member; and cam means integral with said rod for engaging and closing said switch on movement of said cover plate outwardly about said socket means to expose said tube end, said socket means and rod comprise hinge means, and there are further provided means on said hinge means for sealing said tube end with said cover plate sealing member throughout a range of decreasing vacuum as the vacuum cleaner motor is coming to a stop, and said means on said hinge means for sealing comprises means forming a horizontal elongation of each of said sockets for permitting horizontal movement of said rod in said socket means.
US28649A 1970-04-15 1970-04-15 Inlet valve and switch for central vacuum cleaner Expired - Lifetime US3655927A (en)

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Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5226912A (en) * 1987-08-26 1993-07-13 United States Surgical Corporation Combined surgical needle-braided suture device
US5306289A (en) * 1987-08-26 1994-04-26 United States Surgical Corporation Braided suture of improved characteristics
US5349146A (en) * 1992-02-11 1994-09-20 Lindsay Manufacturing, Inc. Combination electrical and suction hose wall outlet
US5504967A (en) * 1994-03-03 1996-04-09 Bernard J. Graham Vacuum operated cleaning apparatus
US5606767A (en) * 1995-05-19 1997-03-04 Crlenjak; Jack Vacuum operated dust and debris removal and collection system
US6108858A (en) * 1998-06-04 2000-08-29 Canplas Industries Ltd. Waste receptacle for a vacuum cleaning system
US6143996A (en) * 1997-11-18 2000-11-07 Aldes Aeraulique Outlet for connecting a vacuum-cleaning hose to a centralized vacuum-cleaning installation
US6292977B1 (en) 1999-09-07 2001-09-25 Canplas Industries Ltd. Vacuum fitting
US20060143851A1 (en) * 2005-01-03 2006-07-06 Jenkins Bradley E Register inlet apparatus for a central vacuum cleaning system
WO2012061884A1 (en) * 2010-11-10 2012-05-18 Kitvac International Pty Ltd Vacuum assembly
US9237832B2 (en) 2012-05-31 2016-01-19 Ivd Global Corporation Illuminated inlet for vacuum cleaning apparatus
US9254070B2 (en) 2012-05-31 2016-02-09 Ivd Global Corporation Inlet for vacuum cleaning apparatus
US20160100725A1 (en) * 2014-10-09 2016-04-14 Alex P. Janssen, Jr. Vacuum portals to alleviate strains and stresses of vacuum cleaning

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2877313A (en) * 1957-11-27 1959-03-10 Constantine E Stoicos Vacuum cleaning apparatus
US3159727A (en) * 1962-09-14 1964-12-01 John E Mitchell Company Inc Vacuum machine wall plug switch
US3283093A (en) * 1965-04-27 1966-11-01 Mabel G Bishop Plastic inlet valve for central vacuum cleaning system
US3291927A (en) * 1965-10-21 1966-12-13 Black & Decker Mfg Co Inlet valve assembly for central cleaning system
US3483503A (en) * 1968-03-20 1969-12-09 Dominick Paradiso Vacuum cleaner wall adapter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2877313A (en) * 1957-11-27 1959-03-10 Constantine E Stoicos Vacuum cleaning apparatus
US3159727A (en) * 1962-09-14 1964-12-01 John E Mitchell Company Inc Vacuum machine wall plug switch
US3283093A (en) * 1965-04-27 1966-11-01 Mabel G Bishop Plastic inlet valve for central vacuum cleaning system
US3291927A (en) * 1965-10-21 1966-12-13 Black & Decker Mfg Co Inlet valve assembly for central cleaning system
US3483503A (en) * 1968-03-20 1969-12-09 Dominick Paradiso Vacuum cleaner wall adapter

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5226912A (en) * 1987-08-26 1993-07-13 United States Surgical Corporation Combined surgical needle-braided suture device
US5306289A (en) * 1987-08-26 1994-04-26 United States Surgical Corporation Braided suture of improved characteristics
US5349146A (en) * 1992-02-11 1994-09-20 Lindsay Manufacturing, Inc. Combination electrical and suction hose wall outlet
US5504967A (en) * 1994-03-03 1996-04-09 Bernard J. Graham Vacuum operated cleaning apparatus
US5606767A (en) * 1995-05-19 1997-03-04 Crlenjak; Jack Vacuum operated dust and debris removal and collection system
US6143996A (en) * 1997-11-18 2000-11-07 Aldes Aeraulique Outlet for connecting a vacuum-cleaning hose to a centralized vacuum-cleaning installation
US6108858A (en) * 1998-06-04 2000-08-29 Canplas Industries Ltd. Waste receptacle for a vacuum cleaning system
US6292977B1 (en) 1999-09-07 2001-09-25 Canplas Industries Ltd. Vacuum fitting
US20060143851A1 (en) * 2005-01-03 2006-07-06 Jenkins Bradley E Register inlet apparatus for a central vacuum cleaning system
US7328478B2 (en) 2005-01-03 2008-02-12 Jenkins Bradley E Register inlet apparatus for a central vacuum cleaning system
WO2012061884A1 (en) * 2010-11-10 2012-05-18 Kitvac International Pty Ltd Vacuum assembly
AU2011326340B2 (en) * 2010-11-10 2013-07-11 Kitvac International Pty Ltd Vacuum assembly
US8938849B2 (en) 2010-11-10 2015-01-27 Kit-Vac International Pty Ltd Vacuum assembly
US9237832B2 (en) 2012-05-31 2016-01-19 Ivd Global Corporation Illuminated inlet for vacuum cleaning apparatus
US9254070B2 (en) 2012-05-31 2016-02-09 Ivd Global Corporation Inlet for vacuum cleaning apparatus
US20160100725A1 (en) * 2014-10-09 2016-04-14 Alex P. Janssen, Jr. Vacuum portals to alleviate strains and stresses of vacuum cleaning

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