Adaptor for central vacuum system inlet valve assembly

An inlet valve assembly for a central vacuum cleaner system is provided with a mounting bracket plate having a circular inlet aperture therethrough and at least one electrical service aperture, and an adaptor for snap engagement with the mounting bracket plate through said inlet aperture. The adaptor comprises a deformable open-ended cylindrical connector of outside diameter slightly greater than the diameter of the inlet aperture, a flange projecting laterally from one end of the connector and adapted to overlie at least a part of the mounting bracket plate including the electrical service aperture, and an outer peripheral groove about the cylindrical connector and adjacent said flange. The deformable cylindrical connector is adapted for insertion into the inlet aperture until the flange abuts the connector plate, whereupon the edge of the inlet aperture snaps into the groove in the outer surface of the cylindrical connector to securely attach the adaptor to the mounting bracket plate.

BACKGROUND OF THE INVENTION 
This application relates to central vacuum cleaning systems, and 
particularly an adaptor for use in an inlet valve assembly employed in 
such systems. 
Conventional inlet valve assemblies consist of an inlet valve having a 
cover plate disposed primarily on the outer surface of a wall, and a 
mounting bracket assembly, usually of metal, and disposed on the inner 
surface of a wall, such as a conventional stud and drywall structure 
commonly used in residential buildings. The inlet valve includes a 
decorative cover or face plate which lies against the outer surface of the 
wall, similar to the cover plate which overlies a conventional light 
switch or duplex outlet. However, in the case of the central vacuum inlet 
valve face plate, the plate has a circular aperture therethrough and a 
cylindrical extension extending from the back of the aperture through the 
wall and adapted to communicate with tubular ducting which leads to the 
central vacuum power unit. The face plate is provided with a spring biased 
flap which lies flush with the surface of the face plate to cover the 
circular opening when the inlet valve is not in use, but which may be 
drawn away from the surface of the face plate against the bias of the 
spring to permit insertion of one end of a hose and nozzle assembly. The 
inlet valve includes, within the cylindrical extension, two electrical 
contacts which coact with the inserted end of the hose and nozzle assembly 
to automatically initiate operation of the central vacuum power unit upon 
insertion. 
The mounting bracket assembly is essentially a flat metal plate which is 
disposed behind the wall and is normally secured to a wall stud or the 
like. The bracket plate is provided with a relatively large inlet aperture 
which receives the cylindrical extension on the rear of the face plate, 
and additional apertures to receive fasteners required to secure the 
bracket plate to a wall stud or the like, to secure the inlet valve face 
plate to the mounting bracket plate, and to permit the passage of 
electrical wires therethrough for connection into the back of the face 
plate and to the aforementioned electrical contacts therein. The mounting 
bracket assembly is further provided with a deformable gasket about the 
inlet aperture to snugly and sealingly receive the cylindrical member of 
the face plate, the gasket being interposed between the mounting bracket 
plate and the end flange of a cylindrical connecting member adapted to be 
connected into the tubular ducting. The flange of the cylindrical member, 
the sealing gasket, and the mounting bracket plate are secured together by 
means of rivets or like securement means, and together form the inlet 
valve mounting bracket assembly. 
When a central vacuum system is being installed in a new residence, the 
inlet valve mounting bracket assembly is installed in a desired location, 
for example, by securing the mounting bracket assembly to one of the studs 
before the drywall is applied, and the tubular ducting is installed 
between the mounting bracket assembly and the central vacuum power unit, 
with the cylindrical connector of the mounting bracket assembly being 
glued or otherwise secured into an end of the tubular ducting. Electrical 
wires are then passed through one of the electrical apertures in the 
mounting bracket plate, and the drywall is applied to the studs with an 
opening being provided adjacent the mounting bracket assembly inlet 
aperture. As a final step in completing the wall and the central vacuum 
system, the inlet valve is applied to the outer surface of the wall, with 
the electrical wires first being connected to the contact connectors on 
the back of the face plate, and the cylindrical extension on the back of 
the face plate being inserted through the inlet aperture of the mounting 
bracket assembly, and snugly retained therein by means of the circular 
gasket to provide a sealed communication between the cylindrical extension 
and the ducting leading to the central vacuum power unit. The face plate 
is then secured to the mounting bracket assembly by insertion of screws or 
like fastening devices through apertures in the face plate and into the 
fastening apertures on the mounting bracket in a manner similar to the 
cover of a conventional light switch or duplex outlet. 
The inlet valve is relatively easy to install in a system such as that just 
described. However, the mounting bracket assembly is relatively expensive 
to produce, in that it comprises a number of parts, i.e., the relatively 
flat mounting plate, the circular gasket about the inlet aperture, the 
flanged cylindrical connector, and the connecting means (usually four 
rivets or screws are employed) for connecting the flange, gasket and the 
mounting plate together. Further, the apertures through which the 
electrical wires pass are normally punched out of the flat plate, with the 
result that their edges are relatively sharp and can readily damage the 
insulating covering on the wires. Any attempt to remove the sharp edges 
would result in considerable additional processing or hand labour, and 
would increase the complexity and cost of production of the mounting 
bracket assembly. 
SUMMARY OF THE INVENTION 
I have found that production of the assembly may be greatly simplified, and 
the problems of wiring damage due to the sharp edges on the electrical 
service apertures eliminated, by utilizing a single adaptor which may be 
snapped into the mounting bracket plate on location, thus eliminating the 
relatively costly preassembly of the mounting bracket assembly, and 
reducing the number of components required to produce a satisfactory 
assembly from seven (plate, gasket, flanged cylindrical adaptor and four 
connecting rivets) to two (plate and adaptor). 
The mounting bracket adaptor in accordance with the invention is formed of 
electrically insulating plastic material, and comprises a deformable 
open-ended cylindrical connector of slightly larger outside diameter than 
inlet the aperture of the mounting bracket plate, and a relatively flat 
flange projecting laterally about one end thereof. The cylindrical member 
is provided with an outer peripheral groove adjacent the flange member 
whereby to receive the edge of the mounting plate inlet aperture for snap 
attachment of the adaptor to the plate with the cylindrical connector 
extending through the inlet aperture and projecting to the rear of the 
plate, and the flange abutting and overlying at least a part of the front 
surface of the plate. 
The flange portion of the adaptor may be provided with apertures 
therethrough having a beaded circumferential lip on the rear surface 
thereof (the same side as the cylindrical projection) adapted for snap 
engagement with at least one electrical service aperture through the metal 
mounting plate to isolate electrical wiring passing therethrough from the 
sharp edges of the plate apertures, and to provide a fully insulated 
opening for the passage of electrical wires therethrough. This additional 
securement also prevents twisting of the adaptor relative to the mounting 
plate during installation.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, FIG. 6 provides a side view, partially in 
section, of a central vacuum inlet valve assembly installed in a wall 1. 
The assembly consists of an inlet valve depicted generally at 10, a 
mounting bracket plate 30, an adaptor 50 and tubular ducting 70. 
The inlet valve 10 is conventional in construction, and consists of a 
decorative cover or face plate 11 an open-ended cylindrical or tubular 
projection 12 projecting rearwardly of the decorative cover, and providing 
communication between the interior of a room and the ducting 70, and a 
cover flap 13 having a circular sealing gasket 14 secured to the inner 
surface thereof to close the room side end of the tubular projection 12 
when the cover flap is in closed position essentially flush with the 
decorative cover. The cover flap 13 is normally spring biased to its 
closed position in a recessed portion of the decorative cover 11. However, 
the flap may be drawn away from the decorative cover in the direction of 
the arrow 15 to open the room end of the cylindrical projection 12 for 
insertion of an end of a vacuum hose and nozzle assembly (not shown). The 
inlet valve is also provided with connectors 16 for connection of 
electrical wiring thereto, which connectors are connected to electrical 
contacts (not shown) on the inner surface of the cylindrical projection 12 
whereby insertion of an end of a vacuum hose and nozzle assembly 
automatically completes a circuit through the contacts to activate the 
central vacuum power unit and induce suction in the hose and nozzle 
assembly. The decorative cover 11 is provided with a pair of fastener 
apertures 18 therethrough for reasons which will later be apparent. The 
foregoing is conventional, and does not, per se, form an element of the 
invention. 
The mounting bracket plate 30, as best shown in FIG. 3, is provided with an 
inlet aperture 31 through which the cylindrical projection 12 of the inlet 
valve may pass, electrical service apertures 32, for the passage of 
electrical wiring such as wires 17 (FIG. 6), therethrough, fastener 
apertures 33, to receive a fastener such as a screw 40 or the like, to 
connect the cover plate, through apertures 18, to the mounting bracket 
plate, and mounting apertures 34 whereby the mounting bracket plate may be 
readily secured to a wall stud or the like by nails, screws, or other 
suitable means, not shown. As it is sometimes desirable to break the 
portion of the mounting bracket plate containing the mounting fastener 
apertures 34 away from the remainder of the plate, the plate may be 
provided with an elongated open slot 35 and lines of weakness 36 to permit 
the portion containing the apertures 34 to be readily broken away from the 
remainder of the plate. 
As best illustrated in FIGS. 1 and 2, the adaptor 50, which is formed of 
electrically insulated material consists of a deformable cylindrical or 
tubular portion 51 and a circular flange 61 projecting from an end 
thereof, with extensions 61a extending therefrom to overlie a portion of a 
surface of the mounting bracket plate. The inner surface of the 
cylindrical portion 51 is provided with a plurality (3 in the illustrated 
embodiment) of circumferential ribs 52, whereas the flange extensions 61a 
are provided with apertures 62 and rearwardly projecting circular beaded 
lips 63. The outer surface of the cylindrical portion 51 is slightly 
larger in diameter than the inlet aperture 31, and is provided, at the end 
adjacent to the flange, with a circumferential slot 64. 
As best seen in FIGS. 4 and 5, the adaptor 50 is assembled to the mounting 
bracket plate 30 by inserting the deformable cylindrical portion 51 into 
the entrance aperture 31 of the mounting bracket plate until the edge of 
the entrance aperture 31 snaps into the slot 64 to retain the two elements 
in assembled relation, as illustrated in FIG. 5. The adaptor is so formed 
that the circular beaded lips 63 are, in assembled position, adjacent the 
electrical service apertures 32 in the mounting bracket plate, and the 
beaded lips are snapped into the apertures 32 to further secure the flange 
elements 61a in position adjacent a surface of the mounting bracket plate. 
Electrical wires such as those illustrated at 17 may then be passed 
through one or other of the apertures 62, depending upon which is most 
convenient for connection to the connector 16 on the face plate, and, in 
this way, the wires never come into direct contact with the metal edges or 
the metal surface of the mounting bracket plate service apertures 32. 
Indeed, even if the flange material surrounding the apertures 62 is torn 
to some extent, the beaded lips 63, which embrace the edges of the service 
apertures 32, will prevent direct contact between the electrical wires and 
the metal edges of the service apertures. 
When the mounting bracket assembly, consisting of the adaptor 50 and the 
mounting bracket plate 30 are assembled as shown in FIG. 5, the assembly 
may be secured to a wall stud or the like, a tubular fitting, such as the 
90.degree. elbow 71 illustrated in FIG. 6 may be secured to the 
cylindrical portion 51 by gluing or the like, and the remainder of the 
tubular ducting, including straight sections such as 72 may be completed 
to connect the opening through the mounting bracket assembly to the 
central power unit (not shown) of the central vacuum system. The dry wall 
may then be applied to the outer surface of the wall studs, with an 
aperture cut away to expose the mounting bracket assembly, and the inlet 
valve may be applied by inserting the cylindrical projection 12 into the 
cylindrical portion of the adaptor, and connecting the face plate to the 
mounting bracket assembly by means of screws 33 or the like, as 
illustrated in FIG. 6. 
The purpose of the circumferential ribs 52 on the inner surface of the 
cylindrical portion of the adaptor will now be apparent. They define an 
aperture slightly smaller in diameter than the outer surface of the 
cylindrical inlet valve projection 12 and thus tightly receive and embrace 
the cylindrical projection, and provide a seal between the outer surface 
of the cylindrical projection and the tubular ducting leading into the 
central vacuum power unit. In the illustrated embodiment, a triple seal is 
provided, by reason of the three circumferential ribs 52. It will be 
appreciated that the numbers of ribs may vary depending upon the quality 
of the seal desired. 
The foregoing detailed description is for purposes of illustration only. It 
will be apparent that numerous variations and modifications may be 
effected by those skilled in the art without departing from the spirit and 
scope of the invention as defined in the appended claims.