US3269352A

US3269352A - Pneumatic warning system

Info

Publication number: US3269352A
Authority: US
Inventors: Roy L Van Winkle
Original assignee: GEOLOGRAPH Co
Current assignee: GEOLOGRAPH Co
Priority date: 1962-12-26
Filing date: 1965-10-13
Publication date: 1966-08-30
Anticipated expiration: 1983-08-30

Description

R. l.. VAN wlNKLE 3,269,352

PNEUMATIC WARNING SYSTEM Original Filed Dec. 26, 1962 Aug. 30, 1966 INVENTOR RY L. VAN WNKLE .BY A

ATTORNEY United States Patent O 3,269,352 PNEUMATIC WARNING SYSTEM Roy L. Van Winkle, Edmond, Okla., assignor to The Geolograph Company, Oklahoma City, Okla., a corporation of Oklahoma Original application Dec. 26, 1962, Ser. No. 247,142, now Patent No. 3,223,068, dated Dec. 14, 1965. Divided and this application Oct. 13, 1965, Ser. No. 495,601 1 Claim. (Cl. 116-65) This appl-ication is a division of my copending application, Serial No. 247,142, tiled December 26, 1962, now Patent No. 3,223,068. This invention relates generally to a pneumatic warning system adapted to operate in conjunction with recording or indicating apparatus. More speciiically, it relates sto an adjustable pneumatic warning system that may be set to provide a warning at desired values of a measured variable.

In the past, it has been possible to obtain warning systems for pneumatic apparatus that will provide satisfactory service provided that the system can be pre-set at a given value and provided, further, that it does not require subsequent adjustment lor frequent changes of the value at whi-ch the warning is to be sounded. Perhaps the greatest difficulty encountered has been the development of a warning system of suiiicient simplicity that it can be adjusted to a certain value of a measured variable and then changed, by a relatively unskilled person, to provide a warning at a different, but desired value of the measured variable.

It is, therefore, one object of this invention to provide an improved warning system lfor use with pneumatic apparatus wherein the system can be easily adjusted to a pre-selected value of 1a measured Variable.

Another object of this invention is to provide an improved warning system that can be easily adjusted Iand will sound an alarm upon an increase above or decrease below a pre-selected value of a measured variable.

Generally, this invention contemplates .a warning system that includes warning means, adjustable means for controlling the value at which the warning means will be actuated, and control means adapted to produce a visual indication of the value at which the adjustable means will actuate.

Other, further, and additional objects and advantages of the invention will become more apparent when the following description is read in conjunction with the accompanying drawing which is a schematic diagram illustrating a warning system, constructed in. accordance with the invention, connected with a pneumatic recording apparatus and adapted to provide an alarm above a certain value and below a certain value of a measured variable.

Referring to the drawing in detail, there is shown a pneumatic transmitter 24 connected by a conduit 36 to a recording servo mechanism 22. The transmitter is also connected by a condu-it to a source of air which is regulated to p.s.i. in a conventional manner (not shown per se) as indicated by the reference numeral 26, the latter numeral also being employed throughout this application to designate ya 20 p.s.i. source of air pressure wherever required. The transmitter is also connected by means of element to a variable Whose condition is to be measured by the servo 22 and whose maximum or minimum condition is to be indicated by the warning system described herein. For example, the element 25 could be an arm connecting with a float (not shown) resting on the surface of drilling mud (not shown) in a mud pit (not shown). In such an instance, the transmitter 24 would have therein a rotatable element movable in response to the pivoting motion of the element 25 and would be adapted to produce an output 3,269,352 Patented August 30, 1966 ICC ' pit level transmitters.)

Various other types of transmitters can be utilized, the exact type depending upon the variable to be measured. One requirement, however, for the transmitter to be used in the warning system disclosed herein is that the transmitter 24 should have an output pneumatic pressure variable between 3 and 15 p.s.i. which is a function of the measured Variable.

The recording servo mechanism 22 fwill, of course, be compatible With the particular type of transmitter 24 employed. Briefly stated, however, a 20 p.s.i. reference pressure is introduced to the servo 22 from the source 26 referred to above. The variable signal between 3 and 15 p.s.i. is also introduced to the servo 22 through the conduit 36. The internal details of the servo are such that the indicating portion thereof Will be moved to a position dependent upon the value of the variable input signal through the conduit 36. (A suitable servo has been found to be a Taylor Servomatic Motor, l' series, as illustrated in catalog 4B20l, issue 2, of the Taylor Instrument Company 'TP-618.)

The transmitter 24 is also connected by means of a conduit 41 to a selector valve 40 which, as will hereinafter appear, is used for calibration purposes. The conduit 41 lis in communication with a conduit 64 through the selector valve 4t)y when the latter provides a ilow path as indicated by the arrow A. Conduit 64 connects upwardly to an on/otf valve 66 and through a conduit 72 to a relay 14. Conduit 64 connects downwardly to an on/oli valve 68 and through a conduit 70 to a relay 20. Gages 44 and 46 are connected to the

conduits

72 and 70 respectively. Relay 14 is connected by means of conduit 52 to the upper end of a shuttle valve 48, the latter being essentially a two-way check valve. Relay 20 connects by means of conduit 54 to the opposite end of the shuttle valve 48. The output of the Vshuttle valve 48 is connected to a booster relay 50` which, in turn, is connected by a conduit 30 to an alarm 16 (indicated as a horn). The rig air supply 38 also connects with the booster relay 50.

The selector valve 40 is connected to an adjustable regulator 62 by means of a conduit 56.

Relay 14 is an adjustable snap-acting relay of the type disclosed in lt/linneapolis-I-I'oneywe'll Regulator Company bulletin -2554, published lune 7, 1960. Relay 14 is a direct-acting relay as will hereinafter appear. Relay 14 is provided with an integral calibrated indicating portion 13 4and an external adjusting knob 15. A pointer 17 which is slidable along the indicating portion 13 is moved by .rotation of the adjusting knob 15.

Relay 20 is another `snap-acting relay which is essentially the same as the relay 14, but is reverse-acting as 'will hereinafter appear. Relay 20 has an integral calibrated indicating portion 19, an external adjusting knob 21 and a pointer 23 which lis movable across the calibrated portion 19in response to rotation of the knob 21.

As indicated above, the relay 14 is a direc-t-acting relay, which means that this relay will be energized or opened when the pressure in the conduit 72 exceeds a predetermined value; below this pressure, the relay 14 will remain closed. Contrariwise, the relay 20 is a reverseacting relay in that it will not be energized or opened until the pressure in the conduit 70 drops below a predetermined value; .above this predetermined value, the relay 20 will remain closed. It will be now assumed that the element 25 on the transmitter 24 is a iioat arm connecting with a float (not shown) resting on the surface of the drilling mud in `a mud pit (not shown). With the system being connected in the manner shown, if the level in the mud pit drops below a predetermined value, the signal in the conduit 72 will increase so as to open or energize the relay 14. When the relay 14 is energized, pressure will be transmitted through this relay into conduit -52 to the shuttle valve 48. The pressure in the conduit will move 'the shuttle valve in such a manner as t-o prevent pressure being transmitted through the shuttle valve int-o the conduit 54. Thus, the pressure transmitted to lthe shuttle valve will pass through the booster relay into conduit 30 to the alarm 16 or, more precisely, actuation of the booster relay `as the result of the pressure transmitted to it from the shuttle valve, will permit passage 4of air from the rig air supply 38 through the booster relay 50 t-o the conduit 30 and to the alarm 16.

Conversely if the level in the mud pit rises above a predetermined value, the signal in the conduit 70 will decrease so as -to open or energize the relay 20. Resulting pressure in the conduit 54 will move the internal mechanism (not shown) of the shuttle valve in the opposite direction to prevent communication with the conduit 52. Thus, pressure passes fr-om the shuttle valve 48 in lthe same manner as described above to the booster relay so Vas to actuate the alarm 16.

The selector valve 40, gages 44 and 46,

valves

66 and 68, and adjustable regulator 62 are provided for the purpose of Calibrating the relays 14 and 20. The dials on the gages 44 and 46 are calibrated in advance to correspond with the units of measurement of the measured variable (not shown) which operates the transmitter 24. Thus, if transmitter 24 is used in a mud pumping system, for example, then gages 44 .and 46 will be calibrated in units of liquid level. Valve 40, for example, is movable into two positions Ito permit flow in two direc- -tions indicated by t-he right-angled .arrows designated by the reference characters A and B, of course, at separate periods of time.

Now, if it is desired to calibrate relay 14, the valve 66 is left open, valve 68 is closed, and selector valve 40 is placed in -a llow condition corresponding to arrow B. Thereafter, the control on adjustable regulator 62 is adjusted until the pressure reading on the gage 44 corresponds to the first desired value (or level) of the variable whose condition is sensed by the transmitter 24. When the gage 44 is brought to the correct or desired value, the adjustment knob on the relay `14 is moved until the alarm '16 is sounded. The relay 14 is now adjusted to 4operate for the condition corresponding to the reading on the gage 44. Thereafter, the valve 66 is closed and valve 68 is opened. Now, the control on the adjustable regulator 62 is adjusted until the pressure reading on the gage 46 corresponds to the second desired value (or level) of the variable. The relay is then adjusted in the same manner as described above with respect to relay 14.

Although the invention set forth herein has been described in terms of changes in liquid level, the condition being sensed by the transmitter 24 need not necessarily be a liquid level. Indeed, it can be a variable pressure, hydraulic or pneumatic or it can be a variable mechanical movement, either rotary or translational. It can be a change in weight or volume. Practically no limitations should be placed upon the type of variable to which the present invention can be adapted. Just so long as the transmitter 24 is capable of producing an output pressure variable between 3 and 15 p.s.i., the systems described herein will be completely operable. It is well known in the art that there are many different types of transmitters or converters which are adapted to change a variable pneumatic pressure, liquid pressure or mechanical movement into a corresponding variable pneumatic pressure. Thus, the selection of a particular transmitter depends upon the type of variable bein-g measured.

Wherea-s the present invention has been described in particular relation to the drawing attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention. For example, the pressure range of the pneumatic signal has been described as being between 3 and 15 p.s.i. and the input operating pressure range of the servos has been described as being between 3 and 15 p.s.i. It should be understood that the applicant does not intend to limit this invention to any particular range, the above being disclosed merely for the sake of preference and in the interest of completeness of disclosure. Actually, any predetermined range can be employed just so long as the same predetermined range is used in a uniform manner. Likewise, the specic oper-ating pressures, such as 20 p.s.i., are not at all critical, but obviously depend upon the requirements and versatility of the units which these pressures operate.

What is clai-med is:

A warning system for indicating when the value of a given variable falls be-low a tirst predetermined value and exceeds a second predetermined value comprising a sensing means adapted to sense the instantaneous value of said variable and to transform the same into a corresponding output pneumatic pressure falling within a predetermined range of pneumatic pressures, a recording device connected to the output of said sensing device for recording the instantaneous value of said variable, a selector valve having two inlets and a single outlet, one inlet being connected to the output of said sensing device and the other inlet of said selector Valve being connected to the outlet of a regulator valve, said regulator valve having an inlet connected to a source of |air pressure, said selector valve being adjustable to place said iirst and said second inlets alternately in communication with the outlet of said selector valve, a pair of on/oi valves each having an inlet and an outlet, the outlet of said selector valve being connected in common to the inlets of said on/oi valves, the rst on/otf valve having its outlet connected to a rst pneumatic gage, a rst pneumatic relay having its inlet connected to the outlet of said rst on/ 01T valve, said -first pneumatic relay having an outlet tand ibeing normally closed but being adapted to open to provide communication between its inlet and outlet when the pneumatic pressure transmitted to said -rst relay from said sensing means falls below said rst predetermined value, the second on/ oft valve having its outlet connected to a second pneumatic gage, a second pneumatic relay having its inlet connected to the outlet of said second on/off valve and having an outlet which will be placed in communication with said inlet when said second relay is opened, said second pneumatic relay being normally closed but being opened when the pressure transmitted to said second relay from said sensing means indicates that the instantaneous value of said variable exceeds said second predetermined value, a twoway check valve having two inlets and a single outlet with its inlets being connected to the outlets of said pneumatic relays, respectively, an alarm device connected to the outlet of said two-way check valve, said rst relay having means adjusting the same to change the pressure required to open said relay, and said second relay having means adjusting the same to change the pressure required to open said relay.

References Cited by the Examiner UNITED STATES PATENTS 3,138,956 6/1964 Falbout et al. 73-316 LOUIS J. CAPOZI, Primary Examiner.