US2894274A

US2894274A - Suction control in surface cleaning tool

Info

Publication number: US2894274A
Application number: US618754A
Authority: US
Inventors: Curtis C Coons
Original assignee: Hoover Co
Current assignee: Hoover Co
Priority date: 1956-10-29
Filing date: 1956-10-29
Publication date: 1959-07-14
Anticipated expiration: 1976-07-14
Also published as: GB806513A

Description

C. C. COONS July 14; 1959 SURFACE CLEANING TOOL SUCTION CONTROL IN Filed Oct. 29, 1956 United States Patent SUCTION CONTROLTISIOiURFACE CLEANING Application October 29, 1956, Serial No. 618,754

Claims. (Cl. 15-421) The present invention relates to surface cleaning tools connected to a source of suction and more particularly to reducing the force required to propel the tool over the surface being cleaned.

An object of the invention is to provide a suction cleaning tool having valve means controlled by the nature of the surface being cleaned to reduce the force required to move the tool along the surface. Another object is to provide a suction cleaning tool having valve means actuated by the surface being cleaned to reduce the suction pressure at the nozzle lips whereby less force is required to propel the tool over the surface. A further object is to provide a suction cleaning tool having valve means biased to closed position by the suction pressure in the tool. Other objects and advantages of the invention will become apparent from the following description and drawing wherein:

Figure 1 is a section along the line 11 in Figure 4.

Figure 2 is a view along the line 22 in Figure 1.

Figure 3 is a sectional view showing the valve in open position.

Figure 4 is a rear elevation of the cleaning tool, and

Figures 5 and 6 are sections along lines 55 and 6-6 in Figure 4.

The embodiment of the invention herein disclosed comprises a nozzle body 10 having front and rear walls 11 and 12, and opposite end walls 13 which terminate in a perimeter nozzle lip 14 defining a nozzle mouth 15 communicating with an air passageway 16 connected to an outlet 17 having a rotatable coupling 18 which is connected to an unshown source of suction, as for example a suction cleaner, to provide suction pressure at the mouth 15 in a manner well known in the art.

In the rear wall 12 of the nozzle above the lip 14 is an elongated air inlet opening 19 provided with a flap valve 20 to which is secured a supporting shaft 21 having its opposite ends 22 rotatably mounted in recesses 23 formed in the rear wall 12 and exposed to the outer surface of the latter. A bracket 24 is attached to the rear wall 12 by a screw 25 to retain the ends 22 of the shaft 21 in the recesses 23 and secure the valve 20 to the wall 12. The valve 20 has a portion 26 above the shaft 21 arranged along the outer surface of the rear wall, and a lower portion 27 along the inner surface of the rear wall 12, and both portions cooperate to cover the opening 19. The portion of the opening 19 above the valve shaft 21 and the upper valve portion 26 are of greater area than the lower portion of the opening 19 covered by the valve portion 27, whereby suction pressure in the air passageway 16 combined with the outside ambient air exerts a force on the upper valve portion 26 to move the valve 20 counterclockwise and bias the valve to its closed position as viewed in Figure 1.

A surface engaging valve operating member 30 is pivotally mounted to the nozzle front wall 11 by a pin 31 secured in a pair of lugs 32 formed on the nozzle wall 11. The member 30 extends across the nozzle mouth 15 substantially in the plane of the nozzle lip 14 and at its .2 rear end 33 is provided with an upstanding bracket 34 having a pin 35 slidably mounted in an elongated opening 36 formed in an arm37 attached to the lower portion 27 of the valve 20. The member 30 is so arranged in the nozzle mouth 15 that it is pivoted upwardly by the carpet entering the nozzle mouth, as indicated at 38 in Figure 3, to move the valve 20 to open position. If the surface being cleaned is non-flexible, as indicated at 39 in Figure 1, the member 30 remains in the lane of the nozzle lip 14 and the valve is retained in its closed position.

In operation, when the coupling 18 is attached by a hose to a suction cleaner a suction air stream is created in the nozzle mouth 15 and air passagewaylfi to remove dirt from the surface being cleaned. If the surface being cleaned is non-flexible as shown at 39 in Figure 1 the member 30 remains substantially in the plane of the nozzle lip 14 and no force is exerted by it to move the valve 20 to open position. The force of suction pressure on the enlarged area of the upper portion 26 of the valve 20 is suflicient to maintain the latter closed to cover the opening 19 and prevent entrance of outside air into the air passageway 16. The suction pressure on the valve portion 26 also maintains the valve operating member 30 in its inoperative position shown in Figure 1.

When the tool is used to clean a surface which reacts to suction pressure and lifts the surface, as shown at 38 in Figure 3, into the nozzle mouth 15 the elevated surface 38 raises the end 33 of the member 30 causing the valve 20 to be shifted to its open position. In this position of the valve outside ambient air passes through the opening 19 into the air passagaway 16 and reduces the effective suction pressure at the nozzle lip 14, whereby the force required to propel the tool over the surface is greatly reduced.

While I have shown and described but one embodiment of my invention, it is to be understood that this embodiment is to be taken as illustrative only and not in a limiting sense. I do not wish to be limited to the particular structure shown and described but to include all equivalent variations except as limited by the scope of the claims.

I claim:

1. A suction cleaning tool comprising a nozzle body having an outlet communicating with a source of suction, means defining a nozzle mouth in said body communicating with said outlet and having lips for engagement with a yieldable surface to be cleaned whereby suction in said mouth draws the surface above the plane of said nozzle lips, means defining a port in said body for passage of outside air into said body to reduce the suction pressure at said nozzle mouth, valve means normally closing said port, surface engageable means movably mounted on said body and connected to said valve means, said surface engageable means disposed in said nozzle mouth substantially in the plane of said nozzle lips and of smaller area than the area of said nozzle mouth to at all times allow passage of air therepast: into said mouth to thereby substantially eliminate the effects of suction pressure thereon, and said surface engageable means actuated by engagement with the yieldable surface, upon the latter being drawn inwardly of said nozzle lips, to shift said valve means to uncover said port for admission of outside air into said body, whereby the suction pressure at said nozzle lips is lessened to reduce the force required to move the tool over the surface being cleaned.

2. A suction cleaning tool as described in claim 1, and said surface engageable means extending laterally between lips of said nozzle mouth.

3. A suction cleaning tool as described in claim 1, and said valve means mounted on said body and subjected to'the suction pressure to bias said valve means to .port closing position.

4. A suction cleaning tool comprising a nozzle body having an outlet for connection to a source of suction, means defining a nozzle mo'uthlin'said body communicating with said outlet and having lips for engagement with the surface to be cleaned, means defining a port in said body for passage of outside air into said nozzle to reduce thesuction pressure at said nozzle mouth, valve means for said port, said valve means subjected to the suction pressure in said nozzle to bias said valve to closed port position, surface engageable means in said nozzle mouth movably mounted on said body substantially in the plane of said nozzle lips and connected to said valve means to shift the latter to open position upon pressure being applied thereto by engagement with a yieldable surface to be cleaned when said surface is drawn inwardly of said nozzle lips.

5. A suction cleaning tool as described in claim 4, and said valve means including a flap valve for said port pivotally mounted on said body and having one portion exposed in said port of greater area than the other and subjected to said suction pressure to bias said valve toward a position to close said port.

References Cited in the file of this patent UNITED STATES PATENTS