US 2966133 A
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Description (OCR text may contain errors)
Dec. 27, 1960 Filed D90. 31, 1958 TRANSMITTER 2 Sheets-Sheet 1 Dec. 27, 1960 A. B. HUBE WATER FLOW DETECTOR Filed Dec. 31, 1958 2 Sheets-Sheet 2 United States Patent Oflfice 2,966,133 Patented Dec. 27, 1960 WATER FLOW DETECTOR Arthur B. Hube, Huntington Station, N.Y., assignor to American District Telegraph Company, Jersey City, N.I., a corporation of New Jersey Filed Dec. 31, 1958, Ser. No. 784,372
5 Claims. (Cl. 116-117) larly, to a vane mechanism for use in such a signaling device.
In closed fluid systems, such as sprinkler systems used for fire-protection purposes in factories, stores, warehouses, and the like, signaling devices are used to communicate abnormal or emergency conditions to a central oflice or station. In such a system, fluid conduits or pipes, each provided with a plurality of sprinkler heads spaced at intervals along the fluid conduit, are connected to a pressure fluid supply, each of the sprinkler heads being held in a closed position by a temperature sensitive element. Under normal conditions, the fluid in the conduit is static, that is, there is little, if any, fluid flow.
Each of the sprinkler heads in the system acts independently of the other sprinkler heads and serves as an independent fire extinguisher for that portion of the building its spray will cover. When a fire occurs in the vicinity of a particular sprinkler head, the element on the particular head operates to open the head and allow fluid from the conduit to spray the area to extinguish the fire. This, of course, causes a sudden flow of fluid in the system from the pressure supply source. Once the spray head is opened, the fluid will continue to flow until the head is replaced, or the system is turned off, even after the fire is extinguished.
The type of building usually provided with a sprinkler system is one which is occupied only during a part of the day or in which large areas are unattended. Hence, a signaling device to detect emergency or abnormal conditions in the fluid system, such as those resulting from a fire or a leak in the system, and to communicate such conditions to a central, attended oflice, is desirable.
One type of signaling device in use in such systems employs a vane pivotally mounted in a fluid conduit of the system, the vane being connected to a transmitter to transmit an electrical impulse to an alarm at a central station when abnormal conditions occur in the system. In order that the vane not impede the fluid flow through the system when a sprinkler head is opened and, at the same time, to maintain the vane in a plane perpendicular to the fluid path when the sprinkler heads are closed, such vanes have been provided with a hinged joint, the hinged joint being biased by a spring or other metallic means to maintain the vane perpendicular to the fluid conduit when the fluid in the system is static but allowing the vane to be pivoted out of the fluid path when abnormal flow occurs. Because of prolonged exposure to fluid such metallic means are subject to corrosion, and the like, require frequent inspections and have not been completely satisfactory.
It is the object of the present invention to provide an improved vane for installation in a fluid flow system as a fluid flow detector for use with a signaling system.
It is a further object of the invention to provide a vane for use with such a device which will render the device responsive to abnormal flow conditions, such as those caused by a fire or leak, without substantially impeding the fluid flow. V
A further object of the invention is to provide a vane for use with such a device which may be readily installed and removed.
A still further object is to provide a vane which will automatically reset itself for subsequent operation after abnormal fluid flow has abated.
Other and further objects, features and advantages of the invention will appear more fully from the following description and the accompanying drawings in which:
Fig. l is a side View, partly in section, of a vane mechanism in accordance with the present invention for use in a signaling device;
Fig. 2 is a front elevational View, partly in section, of the device of Fig. 1;
Fig. 3 is a fragmentary view of the vane in section on the line 3-3 of Fig. 2.
Referring now to Figs. 1 and 2, a housing 10, having a lower flange 12 and an upper flange 14 is mounted over an opening in and attached to pipe or conduit 16 by means of a U-bolt as shown in Fig. 2, a gasket 18 being positioned between the flange 12 and conduit 16 to provide a fluid-tight connection.
A bell-shaped sleeve 22, having a threaded end 24 is fitted into the housing 10 and is connected thereto by spreading the lower edge 26 outward, by welding or brazing or by any other suitable manner. The sleeve 22 is threaded at 28 to receive a collar 30, a gasket or seal 32 being first installed in an annular recess 20 formed A cap 34, having an opening 36, is threaded onto the sleeve 22 at the threaded end 24, a retaining ring 37 and a gasket or seal 38 being positioned between the cap 34 and sleeve 22 to provide a Water-tight connection.
An operating stem 40, pivotally supported by seal 38, is connected near its upper end 42 to one end of a spring 44 and is provided at its lower end with a socket 46. The spring 44 is connected at its other end to a screw 48 adjustably positioned in a support 50 on the fixed member 52. At its upper end 42, the operating stem 40 extends into a transmitter 54 and is positioned adjacent a plunger 55 of a retard mechanism 56 of a type in common use in devices of this nature, the retard mechanism 56 being set to close the contacts 57 a predetermined.
vane 60 is held in spaced position on the pin 64 by spacers 65.
Referring now to Figs. 2 and 3, the vane 60 comprises a flexible web 70 and semi-rigid ribs 72 integrally formed therewith, the semi-rigid ribs extending from the hub 62 outwardly along the flexible web 70. The hub 62, web 70 and ribs 72 are formed as a single unit of the same material, the flexibility of the web and semirigidity of the ribs being attained through a variation in the relative thickness between the web and ribs. Both the web 70 and semi-rigid ribs 72 are resilient, that is, when the web and ribs are released after having been deflected or bent they will return to their initial position. It is preferred to form the vane 60 from a plastic material and polyethylene has been found suitable for this purpose.
In operation, the vane 60 is positioned vertically in a feed line between the main water supply, such as a municipal water supply, and the sprinkler heads, the main water supply being to the right of the vane, as shown in Fig.- 1, and the sprinkler heads being to the left, water flow caused by the opening of the sprinkler heads being in the direction of the arrow in Fig. ,1. Due to the resiliency of the web' and the ribs, the vane60 can be deformed sufliciently for insertion into and withdrawal from the conduit 16 through the opening in the conduit, allowing the device to be readily removed for inspection. When in place, the Web 70 and ribs 72 will readily return to their normal position. With the device in position, the spring 44 is adjusted to position the stem 40 and vane 60 vertically in the housing and conduit 16, respectively. 1 e
With all of the sprinkler heads closed there will be no flow in the conduit 16 and, under usual conditions, the pressure in the conduit on the right and left sides of the vane 60, as shown in Fig. 1, will be equal. Under such condition the web 70 and ribs 72 substantially close the conduit. r f
As aforestated, when connected to-a municipal water supply, the system is subject to minor flows of short duration due to fluctuations in municipal supply and it is desirable that such minor flows not be transmitted to the signaling device. In the device of the invention, when niinor fluctuations occur, the vane 60 pivots the stem 40 thereby expanding the spring 44 and moving the upper end- 42 of the stem 40 away from the plunger 55 freeing the retard mechanism 56 to move at a rate governed by its adjustment. Because of the clearance in the conduit 16 around the vane 60 and the flexibility of the web 70, particularly at its marginal edges, fluid passes from one side of the vane to the other side until the pressure on the opposite sides of the vane equalizes. Since such fluctuations are only slight and of short duration, equalization of the pressure on the opposite sides of the vane is rapid and the spring 44 returns the stem 40 and vane 60 to the vertical position against the plunger 55, as shown in Fig. 1, resetting the retard mechanism 56 before it has moved a suflicient distance to close the contacts 57 to actuate the alarm. Each time a fluctuation occurs in the supply the vane 60 pivots, allowing sufl'icient flow to rebalance the system on the'opposite sides of the vane and, thereafter, the vane returns to its original vertical position. As aforestated, the flow required to rebalance the system is only minor and, due to the action of the retard mechanism, is accomplished without actuating the alarm.
When one or more sprinkler heads are opened, fluid is exhausted from the left of the vane, as shown in Fig. l, causing a continuous flow of fluid from the right to the left of the vane. stem 40 pivot in the housing 10 moving the upper end 42 of the stem away from the plunger 55 thereby freeing the retard mechanism 56 to move at its pre-adjusted rate until the contacts 57-are closed causing the'transmitter, through the leads 58, to actuate the signal in the central station. As the vane 60 pivots, the hub 62 cont-acts the lower end of the housing 10 thereby limiting the pivotal movement of the stem 40 at its upper end 42. However, since the ribs 72 are semi-rigid, they bend under the 'force of'tlie water and, withthe flexible web 70, are
forced against the inner wall of the conduit 16, as shown in dotted lines in Fig. 2, thereby allowing unimpeded flow of fluid. The resilient vane 60 is held by the force of the water against the inner wall of the conduit until the fluid flow. is shut off.
As this flow occurs, the vane 60 and When the sprinkler heads are replaced or the fluid flow otherwise stopped, the resilient vane straightens and, under the influence of spring 44, the stem 40, together with vane 60, is returned to its unactuated vertical position in the conduit. The signal device is then reset for subsequent operation in response to flow in the system.
As used herein and in the claims, the term flexible, when used in connection with-'the web, connotes the characteristicsof thisportion of the vane to bend or deflect with minor flow, such as caused by slight variations in pressure, and the term semi-rigid, when used in connection with the ribs, connotes the characteristi'c of this portion of the vane to remain rigid during minor flow but to bend or deflect upon the occurrence of a substantial flow along the conduit. Due to the resiliency of the web and the ribs, the vane will, in and of itself and without application of an external force, return to its undeflected condition when the fluid in the system returns to a static state. a i
The terms and expressions which have been employed are used as terms ofdescn'ption and not oflimitation, and there is no intention, in the use of such terms and expressions, of excluding'any equivalents of thefeaturcs shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention claimed. 7
What is claimed is:
1. A flow detector for a fluid conduit, comprisinga vane in said conduit, said vane having an area slightlysmaller than that of said conduit cross section, a support adjacent said conduit, said vane having an extended hub portion, said hub portion being intermediately pivoted on said support ona joint transverse to the longitudinal axis of said conduit, a-signal circuit having a switch therein, an operating stem pivotallymounted on said support, one end of said stem having operative engagement with said switch and .the other end of said stem having engagement 'with said hub portion.
2. A flow detector as defined in claim 1, saidjvane being formed of plastic material with the body portion thereof in said conduit being resilient and said hub portion being rigid.
3. A flow detector as defined in claim 2, said hub portion extending in said support and being free for' limited rotation about its pivot in said housing, initial rotation of said vane about said hub portion pivot in' response to a predetermined rate of fluid flow causing rotation of said hub portion to its extreme'position and rotation of said stem to operate said switch while the body portion of said vane remains substantially unde-v across said body portion in mutually divergent relation away from said hub portion.
References Cited the file of this patent UNITED STATES PATENTS 384,570 Grovesteen June 12, 1888 1,830,673 Noren Nov. 3, 1931 1,903,713
Baule Apr. 11, 1933