Abstrict A flow meter alarm device easily attached to and removed from a
flow meter at various locations along the length of the flow meter.
The device is compatible with flow meters which have a float for
measuring flow velocity. The device preferably has two housings,
extending from a third housing having a display surface, that define
an area for receiving a flow meter. The extending housings are preferably
drawn together by a threaded member thereby clamping the device
onto the flow meter. A sensor mounted on the device, preferably
an optical emitter coupled with an optical receiver, is able to
detect the float. When the float is detected, a signal is produced
by the device notifying that the flow rate has fallen outside a
desired range. The device is adjustable to function with flow meters
of various different dimensions.
Claims What is claimed is:
1. A device, for use with flow meters of a type having a movable
float that indicates a rate of flow through the flow meter, and
having a given width between two opposing sidewalls and measured
in a direction transverse to a path of movement of the float, comprising:
a housing assembly including at least one sensor that provides an
output when the float is in close proximity to the sensor, the housing
assembly also including opposing first and second housings, connected
by a third housing, defining a recess having a width at least as
large as said given width enabling the device to be releasably attached
to a flow meter without disconnecting the flow meter from a fluid
inlet or fluid outlet; means for apply a force to at least one of
the opposing first and second housings to releasably secure the
device to a flow meter; and, a signal generator in said housing
assembly providing a signal responsive to said sensor output.
2. The device according to claim 1 wherein said sensor comprises
a first emitter/receiver combination including a first emitter and
a first receiver which cooperates with the first receiver to detect
the float.
3. The device according to claim 2 wherein said sensor further
comprises a second emitter/receiver combination including a second
emitter and a second receiver which cooperates with the first emitter/receiver
combination to detect a direction of movement of the float.
4. The device according to claim 2 wherein said first emitter
and first receiver are of optical design.
5. The device according to claim 1 wherein said means for applying
load includes a threaded member which threadedly engages a tapped
opening in the first housing, the threaded member having an end
making direct contact with the flow meter to secure the device to
the flow meter.
6. The device according to claim 1 wherein said means for applying
a force includes a spring which applies force to the opposing first
and second housings to draw the first and second housings together.
7. The device according to claim 1 wherein said means for applying
a force includes a threaded member cooperating with a tapped member
in said housing assembly to draw the opposing first and second housings
together.
8. The device according to claim 1 including means for reducing
the width of the recess to accommodate flow meters having different
widths.
9. The device according to claim 1 wherein said recess enables
the device to be selectively positioned along a path of the float.
10. The device according to claim 9 wherein the housing assembly
further includes a viewing window provided with a signal line to
facilitate alignment of the device along the path of the float.
11. The device according to claim 1 wherein the signal is an audible
alarm.
12. The device according to claim 1 wherein the signal is a light.
13. The device according to claim 1 wherein the signal is a logic
output.
14. A device for use with various flow meters, each having a different
width and each having a float that indicates a rate of flow through
the flow meter, each said width being measured in a direction transverse
to a path of movement of said float, the device comprising: a housing
assembly including at least one sensor that generates an output
when the float is in close proximity to the sensor, the housing
assembly also including opposing first and second housings, a third
housing connected between said first and second housings to form
a substantially U-shaped configuration and defining a recess, a
width of the recess being adjustable to enable the device to embrace
flow meters of varying width; and, a signal generator responsive
to said sensor output to provide an alarm condition.
15. The device according to claim 14 wherein said sensor comprises
a first emitter and a first receiver which cooperates with the emitter.
16. The device according to claim 15 wherein said sensor further
comprises a second emitter and a second receiver which cooperates
with the second emitter, and wherein the first and second emitters
and receivers cooperate to detect a direction of movement of the
float.
17. The device according to claim 15 wherein said first emitter
and first receiver are of optical design.
18. The device according to claim 14 wherein said housing assembly
further includes means for releasably securing the device to a flow
meter embraced by said device.
19. The device according to claim 14 wherein the first and second
housings are releasably secured to the flow meter by a clamping
device, comprising a threaded member which operates to draw the
first and second housings together.
20. The device according to claim 14 wherein said housing assembly
further includes a threaded member for drawing the opposing first
and second housings together to adjust the width of the recess and
secure the device to a flow meter.
21. The device according to claim 14 further comprising at least
one spacer block connected to the device and positioned between
the opposing first and second housings to adjust the width of the
recess and secure the device to a flow meter.
22. The device according to claim 21 wherein said spacer block
includes protrusions, and wherein the first and second housings
include apertures which receive the protrusions to align and secure
the at least one spacer block to the device.
23. The device according to claim 21 wherein said spacer block
includes at least one ledge to align the device on the flow meter
with the path of the float such that the at least one sensor is
positioned to accurately detect the float.
24. The device according to claim 15 wherein said recess is designed
to enable the device to be slidably mounted and removed without
the need to disassemble the device.
25. The device according to claim 24 wherein said housing assembly
further includes a transparent window having a signal line that
facilitates alignment of the device along the path of the float.
26. The device according to claim 25 wherein said signal line
is substantially parallel to an imaginary center line extending
between the emitter and the receiver.
27. The device according to claim 26 wherein the signal line is
offset from a center line of the device and is positioned closer
to one edge of the housing.
28. The device according to claim 14 wherein the signal is an
audible alarm.
29. The device according to claim 14 wherein the signal is a light.
30. The device according to claim 14 wherein the signal is a logic
output.
31. A combination flow meter and device unit, comprising: a flow
meter having a movable float that indicates a rate of flow through
the flow meter, the flow meter also having a given width measured
in a direction transverse to a path of movement of the float and
being respectively connected to a fluid inlet and a fluid outlet;
and, a device having a housing assembly including at least one sensor
that provides an output when the float is in close proximity to
the sensor, the housing assembly also including opposing first and
second housings, connected by a third housing, defining a recess,
having a width at least as large as the width of the flow meter,
that enables the device to be easily attached to and removed from
the flow meter without disconnecting the flow meter from the fluid
inlet or fluid outlet, the device further having means for applying
a force to the opposing first and second housings to releasably
secure the device to the flow meter.
32. The combination unit according to claim 31 wherein said sensor
comprises a first emitter/receiver combination including a first
emitter and a first receiver which cooperates with the first receiver
to detect the float.
33. The combination unit according to claim 32 wherein said sensor
further comprises a second emitter/receiver combination including
a second emitter and a second receiver which cooperates with the
second emitter to detect the float, and wherein the second emitter/receiver
combination cooperates with the first emitter/receiver combination
to detect a direction of movement of the float.
34. The combination unit according to claim 31 wherein said means
for applying a force includes a threaded member which threadedly
engages a tapped opening in one of said first and second housings,
the threaded member contacting a sidewall of the flow meter to secure
the device to the flow meter.
35. The combination unit according to claim 31 wherein said means
for applying a force includes a spring which applies force to the
opposing first and second housings to draw the first and second
housings together.
36. The combination unit according to claim 31 wherein said means
for applying a force includes a threaded member cooperating with
a tapped member in said housing assembly to draw the opposing first
and second housings toward one another.
37. The combination unit according to claim 31 further comprising
at least one spacer block, positioned between the opposing first
and second housings, for adjusting a width of the recess.
38. The combination unit according to claim 37 wherein said spacer
block includes protrusions, and wherein the first and second housings
include apertures which receive the protrusions to align and secure
the at least one spacer block to the device.
39. The combination unit according to claim 38 wherein said spacer
block includes at least one ledge to properly position the flow
meter within said recess to align the at least one sensor with the
path of the float such that the at least one sensor is positioned
to detect the float.
40. The combination unit according to claim 31 wherein said recess
enables the device to be slideably moved in directions aligned with
and transverse to a length of the flow meter.
41. The combination unit according to claim 31 wherein said housing
assembly further includes a viewing window provided with a signal
line that facilitates alignment of the device along the length of
the flow meter.
42. The combination unit according to claim 31 wherein the signal
is an audible alarm.
43. The combination unit according to claim 31 wherein the signal
is a light.
44. The combination unit according to claim 31 wherein the signal
is a logic output.
45. An alarm device for use with flow meters, comprising: a substantially
U-shaped housing assembly composed of first and second housings
each joined near one end to a third housing forming the U-shaped
configuration; a sensor mounted in one of said first and second
housings for sensing a movable member in a flow meter to provide
an alarm condition; opposing surfaces of said first and second housings
positioned to embrace opposing sidewalls of a flow meter, said opposing
surfaces having shapes conforming to a shape of the flow meter opposing
sidewalls enabling the device to be slidable along said opposing
sidewalls in first and second directions transverse to one another;
and, means for releasably clamping the device to a flow meter by
exerting a clamping force only on said opposing sidewalls.
46. The alarm device according to claim 45 further comprising
a plurality of spacers of differing thickness and each designed
to be releasably joined to at least one of said opposing surfaces
to accommodate flow meters of differing widths measured between
said opposing sidewalls.
47. A method of providing a signal responsive to a rate of flow
as indicated by a flow meter of a type having a movable float, the
flow meter having a given width between two opposing sidewalls measured
in a direction transverse to a path of movement of the float, the
method comprising: placing a housing assembly on the flow meter,
the housing assembly including at least one sensor that provides
an output when the float is in close proximity to the sensor, the
housing assembly also including opposing first and second housings,
connected by a third housing, defining a recess having a width at
least as large as said given width, enabling the housing assembly
to receive the flow meter within the recess and to be releasably
attached to the flow meter without disconnecting the flow meter
from a fluid inlet or a fluid output; applying a force to at least
one of the opposing first and second housings to releasably secure
the device to a flow meter; and generating a signal responsive to
said sensor output.
48. The method of claim 47 wherein the generating step generates
at least one of an audio and a visual signal.
49. The method of claim 47 wherein the step of applying a force
includes the step of turning a threaded member cooperating with
a tapped member in said housing assembly to draw the opposing first
and second housings together.
50. The method of claim 47 wherein the step of placing the housing
assembly includes the step of aligning the device along a path of
the float using a viewing window located on the housing assembly.
51. The method of claim 47 wherein the step of placing the housing
assembly includes the step of inserting at least one spacer block
between the opposing first and second housings to reduce the width
of the recess to accommodate a flow meter of reduced size.
52. A method of providing a signal responsive to a rate of flow
as indicated by a flow meter of a type having a movable float, the
flow meter having a given width between two opposing sidewalls measured
in a direction transverse to a path of movement of the float, the
method comprising: placing housings of first and second sensing
devices on the flow meter, each housing including at least one sensor
that provides an output when the float is in close proximity to
the sensor, each housing having a recess for receiving the flow
meter, and releasably securing the first and second sensing devices
to the flow meter; and slideably moving the housings along the flow
meter to provide signals for different flow rates.
53. The method of claim 52 wherein the step of slideably moving
the housings includes the step of providing viewing windows, located
on each of the housings and substantially aligned with respective
beams created by their associated sensors, to facilitate alignment
of each of the devices along the path of the float.
54. The method of claim 53 further comprising providing each viewing
window with a signal line displaced from a longitudinal central
axis of its associated housing so that the signal line is closer
to one edge of its associated housing and further away from an opposite
edge of its associated housing, and mounting the housings upon the
flow meter in orientations to enable the viewing windows to be positioned
closer to one another than in another orientation.
55. The method of claim 53 wherein providing each viewing window
further comprises providing each viewing window to be of a size
sufficient to view graduations and indicia on the flow meter to
further facilitate alignment of each device at a desired location
along the flow meter.
Description FIELD OF INVENTION
[0001] The present invention relates to flow meters. More particularly,
the present invention relates to a novel device easily attached
to and removed from a flow meter for signaling when flow rates reach
a selected value.
BACKGROUND
[0002] Conventional flow meters typically utilize a float member
moveable along the flow meter housing. Such movement may or may
not be guided by a float rod. In either case, the float moves to
a position representative of flow rate.
[0003] In general, the flow rate is determined by visual inspection
without automated systems for signaling when flow rate falls outside
a desired range.
[0004] It is desirable to provide a device easily attached to and
removed from a flow meter to signal changes in flow rate, especially
critical changes, and further to have a device which may accommodate
flow meters of different sizes.
SUMMARY
[0005] The present invention provides a device designed to be easily
mounted upon and removed from a flow meter, without disturbing the
flow meter as installed, to signal when flow rates reach a given
reading and/or fall outside of a desired range. Spacer members,
designed for mounting on the device, enable use of the device with
a number of flow meters of different sizes.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The present invention will be understood from a consideration
of the drawings wherein like elements are designated by like numerals
and, wherein:
[0007] FIGS. 1 2 and 3 respectively show front, side, and top
views of a device embodying the principles of the present invention
in combination with a flow meter.
[0008] FIG. 4 is a sectional view of the device of FIG. 1 omitting
the flow meter, looking in the direction of arrows 4-4.
[0009] FIG. 5 is an isometric view of the device of FIG. 1 in combination
with a first and second spacer block.
[0010] FIG. 5a is an isometric view of the second spacer block.
[0011] FIG. 6 is a top view of the device of FIG. 1 in combination
with the first and second spacer blocks to accommodate a flow meter
having outer dimensions which differ from the flow meter of FIGS.
1-3.
[0012] FIG. 7 is an isometric view of the device of FIG. 1 showing
the beams directed by the emitters to their associated receivers.
[0013] FIG. 8 is a flow diagram showing the two operating sequences
of the device of FIG. 1.
[0014] FIG. 9 is a top view of an alternative embodiment of the
present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0015] To facilitate an understanding of the present invention,
the invention will be described with reference to a rotameter or
variable area type flow meter. However, those of skill in the art
will realize that the device embodying the teachings of the present
invention is usable with any type of flow measuring device that
utilizes a float.
[0016] Making reference to FIGS. 1-3 a flow meter 10 is shown
therein comprising a hollow, rectangular-shaped outer flow meter
body 12 formed of a material having at least a transparent portion
enabling viewing of the float 14. The float 14 is free to travel
along the length of the flow meter. Flow meter 10 is adapted to
be connected with a flow source via inlet 12a and outlet 12b. Fluid
flow rate through the flow meter 10 is measured by means of float
14 which moves toward outlet 12b as flow velocity increases, the
flow rate being determined by graduations provided along the rotameter
housing.
[0017] In a preferred embodiment, the device 20 comprises housing
assembly 22 which includes a first housing 22a, a second housing
22b, and a third housing 22c. Housings 22a and 22b are drawn toward
one another to secure the device 20 to flow meter housing 12 by
means of a clamping force. The clamping force is provided by screw
24 which threadedly engages a tapped opening 26b in a clamping pin
26 extending through third housing member 22c. The head 26a of pin
26 rests on a circular shoulder 31a in member 31 while the circular
flange 24a of screw 24 rests against the outer surface of member
33 to draw the first housing 22a and second housing 22b toward
each other thereby securely attaching device 20 to flow meter housing
12. Loosening screw 24 allows the device to be easily removed and/or
re-positioned along the length of flow meter housing 12. Screw 24
in the preferred embodiment is a thumbscrew, although any similar
threaded fastener could be used. As an alternative embodiment, referring
to FIG. 9 a spring 124 in combination with a pin 131 extending
through housings 22a-22c, exerts a force on housings 22a and 22b
to draw the first and second housings together thereby eliminating
the need for a screw. As another alternative embodiment, the first
and second housings (22a,22b) could remain fixed, and the device
frictionally secured by a threaded member threadedly engaging a
tapped opening located on one of the first or second housings, one
end of the threaded member making direct contact with flow meter
housing 12. The threaded member may be provided with a rubber or
rubber-like end cap to prevent the flow meter housing from being
damaged and to enhance the frictional engagement.
[0018] Making reference to FIGS. 4-6 in applications where the
device 20 is intended for use with a flow meter having smaller dimensions
than that shown in FIGS. 1-3 spacer blocks 28 and 30 are respectively
attached to covers 32 and 34 each of which forms part of the housings
22b,22a. Projections 28a and 30a provided on spacer blocks 28 and
30 are sized to mate with openings in their associated covers, such
as opening 32a in cover 32 to provide an aligned snap fit therebetween.
Device 20', fitted with spacer blocks may be attached to a flow
meter 10', functionally similar to flow meter 10 but having a width
W.sub.1 smaller than the width W of flow meter 10. Ledges 30b and
28b also assist in properly aligning the sensors of device 20' with
the path of movement of float 14' of the flow meter 10'. Screw 24
is tightened to provide a clamping force to secure device 20' onto
flow meter 10' in the same manner as described above with respect
to flow meter 10. Clearance apertures such as the apertures 30c
in the spacer blocks 28 and 30 provide for the passage of light
from emitters 40 40' to receivers 44 44'. Similar clearance apertures
3536 are provided in covers 32 and 34 which are also aligned with
the emitter and receiver. Spacer blocks of different dimensions
can be used to accommodate flow meters of different dimensions.
As an alternative embodiment, spacer blocks could be attached to
housings 22a and 22b via T-shaped slots in the housings which cooperate
with mating T-shaped protrusions on the spacer blocks.
[0019] Other flow meters having widths only slightly different
from the width of the first flow meter can be accommodated by the
device without use of the spacer blocks. The screw 24 in cooperation
with the clamping pin 26 allows for some variation in flow meter
width.
[0020] As an alternative embodiment, housing 22c and pin 26 may
be made shorter and screw 24 may be lengthened to provide greater
adjustment range in width. This would provide a greater range of
travel of the housing 22a relative to housing 22b, allowing the
device to be affixed to different sized flow meters without the
use of spacer blocks. It should further be noted that the spacer
blocks, in addition to accommodating flow meters of differing widths,
also provide for alignment of the emitter and receiver with the
float 14 by way of the ledges, such as the ledges 30b shown in
FIGS. 5 and 5a.
[0021] Making reference to FIGS. 1 4 and 7 housing 22a, comprised
of covers 33 and 34 contains optical emitters 40 40' mounted on
a circuit board 42. Optical emitters 4040' cooperate with optical
receivers 4444' and a microprocessor 47 mounted on circuit board
46 provided in housing 22b comprised of covers 31 and 32. Emitters
4040' respectively direct light to receivers 4444'. Cover 34 protects
the optical emitters and associated circuitry and provides a surface
to interface with the flow meter housing 12 or a spacer block 28.
Similarly, cover 32 protects the optical receivers and provides
a second surface to interface with the flow meter housing 12 or
second spacer block 30. Apertures 35 and 36 in covers 32 and 34
(together with clearance apertures in the spacer blocks) respectively
allow the transmission of light between the emitters 4040' and
receivers 4444'. Alternatively, the optical emitters may be located
in the housing 22b and the optical receivers located in housing
22a. Alternatively, the emitters and receivers may be located in
the same housing 22a or 22b and employ a reflective technique to
detect the presence of float 14. Further, those skilled in the art
will recognize that other types of sensors including magnetic, inductive,
capacitive, and ultrasonic may be used to detect the presence of
the float 14. Depending on the type of sensor used, the sensor and
associated electronics may be housed in housing 22c with housings
22a and 22b serving as purely structural elements.
[0022] A signal line 50 inscribed on a transparent sight window
48 provided in housing 22c indicates the position where float 14
will enter the light beam emitted by the optical emitters 4040'
and directed to the optical receivers 4444'. The transparent window
also enables graduations and/or numeric legends on the flow meter
to be easily viewed. Signal line 50 enables the user to accurately
position the device 20 at a desired location along flow meter housing
12. The emitter 40 receiver 44 and sight window 48 in one embodiment,
are displaced from a center line (note line 4-4 of FIG. 1) and are
preferably located near edge 64 on housing 22c. This enables two
devices to be mounted as close as possible to one another enabling
the threshold settings represented by the sensing lines to be positioned
as close as possible when two devices are being used on the same
flow meter.
[0023] A second device 20" shown in dotted fashion in FIG.
1 may be mounted upon flow meter 10 with its edge 64" facing
edge 64 of the first device 20. Using this orientation the devices
20 and 20" and especially the sensing lines, may be positioned
close to one another.
[0024] Power is supplied to device 20 from a suitable source (not
shown) and logic is outputted from device 20 to a remote data collection
device (not shown) via the power and logic connector 52. In the
preferred embodiment, power and logic connector 52 extends from
one end of housing 22b remote from the housing 22c. If desired,
the power and logic connector 52 can extend from housing 22a or
from housing 22c. In still another embodiment, a battery may be
provided in the device 20 to supply power and the logic (binary)
output function can be omitted or provided via wireless means.
[0025] Making reference to FIGS. 1 4 6 and 7 display 56 is
comprised of a red LED and a green LED arranged behind a translucent
window and located on the housing 22c adjacent to the transparent
window. When power is supplied to the device, the green LED is illuminated
and the device is operational in a latching mode. In latching mode,
when the float enters the beam created by emitter 40 an audible
alarm 58 located on circuit board 42 sounds, the red LED is illuminated,
and the logic output changes state i.e. one binary state for normal,
opposite binary state for abnormal. The logic (binary) output is
conveyed through the power and logic connector 52 and may be coupled
to various types of data collection and computer systems recognized
and well known by those skilled in the art. The device returns to
normal operation only after the reset button 62 extending outwardly
from housing 22b, is manually pressed to reset device 20. Note that
the second emitter 40' and receiver 44'are not required for the
device to operate in latching mode.
[0026] By pressing and holding the reset button 62 for a given
interval when power is applied to device 20 the device operates
in auto-reset mode. In auto-reset mode, the device utilizes both
emitters 4040' and receivers 44 44' to determine both the float
location and its direction of movement by way of an internal program
provided in microprocessor 47 coupled to receivers 4444'. Emitter
40 and emitter 40' are positioned in close proximity to each other
such that float 14 is able to enter upper beam UB and lower beam
LB substantially simultaneously. Beams UB and LB are represented
by broken center lines extending between their respective emitter
and receiver. It should be noted that the sensing line 50 is substantially
parallel to the beam LB, for example, to facilitate adjustment of
the device 20 along the flow meter 10. In auto-reset mode, when
the float enters the lower beam LB created by emitter 40 the audible
alarm 58 sounds, the red LED is illuminated, and the logic output
changes state. If float 14 continues to move upward into the beam
UB and is displaced from beam LB, the logic output remains unchanged
and the audible alarm continues. If float 14 moves downward and
is initially displaced from beam UB and thereafter leaves beam LB,
the internal program in the microprocessor 47 determines that float
14 moved below beam UB, thereby turning off the audible alarm and
providing a logic output indicating normal operation, responsive
thereto. Thereafter, the green and red LEDs will flash until the
reset button 62 is pressed.
[0027] A variety of different procedures could be used for returning
the device to normal operation after the float is sensed, such as
employing a timer so no user intervention is required. Also, other
methods of signaling that the float has been sensed, such as a wireless
radio transmission, are readily recognized by those skilled in the
art. Those skilled in the art will further recognize that the reset
button 62 the LED display 56 and the audible alarm 58 could be
located on the housing 22c, or alternatively, on any other suitable
location on the device. |