US359673A - Low pbessuees - Google Patents

Description

(No Model.) 5 sneezssneet 1 M. W. GROVESTBEN. APPARATUS FOR GONTROLLING LOW PRESSURES.

No. 359,673. Patented Mar. 22, 1887.

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M GROVE STEEN. APPARATUS FOR CONTROLLING LOW PRESSURE3. No. 359,673. v Patented Mar. 22. 1887.

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(No ModeD M. W. GROVESTEEN.

APPARATUS LEGR CONTROLLING LOW PRESSURBS. No. 859,673.

Patented Mar 22. 1887.

WITNESSES:

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{No Model.) 5 Sheets-Sheet 5k M. W. GROVESTEEN.

APPARATUS FOR CONTROLLING LOW PRESSURES.

Patented Mar. 22, 1887.

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MILTON \V. GROVESTEEN, OF NEW YORK, N. Y

APPARATUS FOR CONTROLLING LOW PRESSURES.

SPECIFICATION" forming part of Letters Patent No. 359,673, dated .March 22, lilffl.

Application filed December 17, 1885. Serial No. 186,001. (No model.)

To all whom it may concern.-

Be it kn own that I, MILTON \V. G novusrnnN a citizen of the United States, residing in the city of New York, in thecounty and State of New York, have invented certain new and useful Improvements in Apparatus for Controlling Low Pressures, of which the folowing is a specification.

My invention relates to an organization of apparatus employed for controlling and regulating low pressuressuch, for instance, as the pressure of gas in street'mains.

The object of the invention is to provide automatically-operating apparatus which shall maintain any required pressu re approximately constant at any and at various dilt'erent points which may be more or less distant.

The invention will, for convenience, be described in its application to a gas supply sys tem.

It consists, generally, in organizing an apparatus in substantially the following manner: At the most distant point or at the point of lowest pressure in a system there is located a polechanging or other suitable form of circuit controlling device, the movements of which are governed by the variations in press ure of the gas in the street-main. This device is designed to transmit electric impulses or currents of the required character for controlling a valve located at the supply-reservoir or source for that district. The circuit-controlling device is so organized that it may be set to respond when any given pressure is exceeded or when the pressure falls below a given point, and to automatically adjust the position of the valve controlling the supply; and it is further organized so that it may either automatically change the degree of pressure which shall be maintained during different times of the day or night or be operated from the central station to so change the degree.

The controlling device for the supply-valve consists, generally, of a cylinder containing a hollow chamber capable of rising and falling within the cylinder. It is designed that the pressure of the gas shall tend to raise this chamber and thereby close the supply-valve. This tendency is counteracted by the pressure of air or other gas above the chamber, which tends to drive it downward and thereby open the valve. The equilibrium between these two pressures is destroyed in favor of one or the other of the pressures by means of the circuit-controlling device above referred to. For V this purpose it is necessary only to increase or decrease the pressure above the airchamber, accordingly as it is necessary to open or close the gas-supply valve. To this end two electro-magneticall y operated valves are employeth-onc controlling the air-inlet of the cylinder and the other controlling an outletopenin These valves are controlled preferably through the instru mentality of a polarized relay included in the circuit, which is controlled by the apparatus located at the point determining the pressure. \Vhen the pressnre is to be increased, the polarized relay serves to complete a circuit through the magnetcontrolling the inlet-valve, and when it is to be decreased it closes a circuit through the other magnet. Suitable devices are employed for preventing an excess of pressure on the part of either the gas or the air, thereby preventing an undue increase or decrease in the gas-supply.

For the purpose of avoiding any possibility of failure to operate on the part of the transmitting apparatus, there is placed at the station supplying the district a pressure-gage, which is provided with a moving arm and contact-points, which may be adjusted so that a circuit will be completed through one or the other of the electromagnetic valve-controlling devices, provided the pressure which it is designed shall be maintained in the main shall be exceeded or becomes too low by reason of any failure on the partof the controlling apparatus.

The invention involves certain other fea titres-such, for instance, as a device for testing the circuits and sounding alarms upon failure of the apparatus to opcrateall of which will be specifically described hereinafter.

In the accompanying drawingswhich illustrate an organization of apparatus embodying the invention, Figure 1 is a front elevation of the circuit-controlling device or transmitter, and Fig. 2 is a plan view of the same. Fig. 3 is a side elevation, partly in section, of the pressure-gage. Fig. 3 is a side view of aportion of the same. Figdis a side elevation,

partly in section, of the valve-controlling device, together with the electromagnetic valveoperating apparatus. Figs. 4 and 4" are details of the same. Fig. 5 illustrates the geir eralorga-nization ofcircuits. Fig. 6 illustrates a modification of the device employed for vary-- ing thelimits between which the pressure shall be maintained.

Referring to the drawings, A represents a gas-main, from which there extends a pipe leading to a prcssure-controlling apparatus. This apparatus consists of a cylinder, a, closing the pipe a, and containing a movable airchamber or float, a which carries a rod, (L The pipe a,which leads from the main, extends within a chamber, a, formed within the cylinder. A quantity of water or other fluid normally fills the cylinder to a point lower than the open end of the pipe a, and it is designed that the increase of the pressure in the main, and therefore through the pipe a, shall force the water in the jacket or chamber a downward, thereby causing the float to rise. Likewise a decrease in the pressure will allow the water to rise to a greater height in the chamber or jacket a thereby causing the water in the compartment containing the float to fall. In this manner the rod (0 will be caused to rise and fall with the variations in the pressure of the main.

The rod a carries atits upper extremity four contact springs or arms, I), I)", b, and If. The arms I) and b are in electrical connection with each other and likewise the arms I) and Z)"; but the two pairs thus formed are insulated from each other, being supported upon a block, if, of insulating material. The four arms are designed, respectively, to make contact with insulatedpoints c, 6-, c", and c. The arms I) and I) extend above their corresponding points, 0 and 0 while the arms Z) and I)" extend beneath their corresponding points, 0 and c. If then the pressure in the main decreases below a certain point, the springs I) and b will touch against and rest upon the points 0 and c. When the pressure is increased beyond a certain point, then the springs Z/and b" will touch the points 0 and 0'', respectively. This device constitutes a circuit-controller or pole-changing device, and the contacts thus made are de signed to transmiteither a positive ora negative current over a main line, L, for the purpose of controlling the supply-valve. This isaccomplished in the following manner:

One pole of a battery, Osay the positiveis connected, by a conductor, 1, with the arms I) and Z), while the negative pole is connected bya conductor, 2, with the arms b and 23*. The points a and c are connected by conductors 4 and 5 with the main line L. The points 0* and c are connected by conductors 6 and 7 with theearth at E. It will be evident, therefore, that when the arms I) and I) rest upon their points the negative pole of the battery 0 will be connected through the arm I) and point 0 and conductors 6 and 7 with the earth at E, while the positive pole is connected by the conductor 1, spring I), point e, and conductors 4 and 5 with the line L, and thus a positive current will be sent. Vhen, however, the springs 12 and I) rest against their corresponding contacts, the positive pole will be connected through conductor 1, spring I), point 0, and conductors 6 and 7 with the earth, while the negative pole is connected through conductor 2, spring b", point 0*, and conductors 4 and 5 with the line. As it is desirable that the limits at which these springs shall make contact with their respective contactpoints may be varied autonmtically,the latter are supported upon a movable frame, D, the vertical position of which is controlled by a cam, d.

This cam is preferably operated by a train of clock-work, d.

The eccentricity of the cam may be modified according to the time and degree of the I changes required in the normal pressures.

Thus, if it is desired that the pressure shall remain less during the day-time than at night, then the cam is so shaped that the frame D shall be allowed to fall during theday'to its causing a current to be transmitted, the points i c and c are carried upon a movable support. 0', which is adjustable vertically by means of a screw, 0". Likewise the points 0 and c are carried upon a support, 0', which is adjustable by means of a screw, c. It is evident that by increasing the distance between the vertical planes in which these points lie the variation in pressure which is normally permitted will be increased, and vice versa.

The mainline L leads through the coils of a polarized relay, F, to the earth at G. There is preferably also included in this line an electromagnet, H, for causing an alarm to be given upon a bell, h, in any suitable manner when the circuit is closed. The armaturef of the polarized relay Fis provided with. two contactpoi11ts,f a'ndf the former of which is connected by a conductor, 9, through the coils of an electro-magnet, K, with a contactpoint, 70 which will be hereinafter described, while the other point, f is connected by a conductor, 10, through the coils of an electro-magneu-K, with a corresponding point, 75. Between the two points k and In there extends a restingcontact, 75, which is connected with the earth by the metal casing of the valve. One pole of a local battery, 0, is connected by a conductor, 12, with the armature-lever fof the relay, while the remaining pole of the battery is connected with the earth at G* by a conductor, 13. Vhen, therefore, a positive current is sent over the line L the polarized arma- ITO turef strikes one of the points-say the point f -and closes a circuit through the electromagnet K, provided the point rests against its resting-contact If, however, a negative 5 current is sent to line, then the armature-lever fwill rest against the pointy and close a circuit through the magnet K provided the point It is against its resting-contact If.

The electro-inagnet K is employed for controlling a valve, M, for opening and closing a pipe, m, leading to a source of compressed air or other fluid. A case surrounds the electro-magnet K, and the air entering through the pipe m escapes through a pipe, m, into 15 the upper portion of a cylinder, N. The electro-magnet K controls avalve, M fol-opening and closing a pipe, m leading from the cylinder N. This cylinder is somewhat similar to that described with reference to thecircuit-controlling device, and is employed for operating a balanced or equilibrium valve, P, which isincluded within thesupply-pipe for the system. Within the cylinder there is'contained an air-chamber or float, a, surrounded by water, as indicated at n. Within this chamber there extends a pipe, if, leading from the gasmain. There will therefore be exerted upon the airchamber a pressure depending'upon the pressure in the gas-main. It is designed that when thepressure at the distant point in the system becomes too great, then the valve 1? shall be closed, (more or less,) as required, to diminish the supply, and vice versa. To this end a rod, is connected with the valve P, and this rod is connected with the wall of the air-chambern. If, therefore, the air-chamber be raised the valve 1? will be closed, and vice versa. of the air-chamberis controlled consists in establishin g an equilibrium between the pressure exerted by the gas beneath the chamber and the air which is introduced under pressure above the chamber in the cylinder N through the pipe m The pipe m may be connected directly with the pipe in through a short sec tion olt' pipe, which is normally closed by a stop-cock. By means of this the air may be caused to enter the cylinder N independently of the valve M.

Any suitable source of air or gas under pressure is connected through the valve M with the pipe m, leading to the cylinder. .Vheu this valve is opened then the pressure of the gas or air above the chamber is increased, provided the normal pressure of the supply 01 the latter is in excess of the pressure of the gas flowing into the main. So long, therefore, as the valve M remains open the pressure above the chamber will continue to increase, thereby driving the Heat it downward, and thus opening the supply-valve P. If, on the other hand, the valve M be open, then the air or gas is allowed to escape from the cylinder N through the pipe m", so that the air-chamber will rise and close the balance-valve.

The means whereby one valve or the other Th e method whereby the position is opened have already been described, and it will be evident that accordingly as apositive or negative current is sent the electromagnet K or K willbe operated. For the purpose, how ever, of preventing too great a movement on the part of the air-chamber n. the circuit-interrupting device, consisting of the contacts k170 and k is employed. The last-named contact is connected with the earth, as already described, through the metal casing, and whichever circuit is closed the connections are through this contact. Upon the air-chamber a there is carried an arm, of, extending between the two contactsprings k and k and, accordingly as the chamber rises or falls beyond a certain predetermined point, it will strike against the corresponding spring (which will be the one with which the circuit is completed, in order to cause the chamber to move in that given direction) and press it away from the resting-contact, thereby interrupting the circuit. The interruption of the circuit which will thus be occasioned will cause the valve M or M to close, and thus prevent a further movement of the airchamber. It may, however, sometimes chance that the valve may fail to operate, and to provide against any such contingency there are applied to an arm, n, which moves with the air-chamber, two adjustable contact-points, k and k, which are electrically connected with each other and, through an alarm-bell, Q, with the battery 0". The arm n is in electrical connection with the earth through the casing of the valve, and therefore should either valve fail to close when the ground-connection of the local battery is interrupted, then the further movement of the airchamber will cause a circuit to be completed through the alarm-bell Q, and thus give an audible alarm, calling attention to the fact. In the two pipes m and m leading to the cylinder, there are respectively included stop-cocks q and q, by means of which the pipes may be closed manually, when, for instance, attention has been called by the alarm Q to the fact that the electro-magnetic valves have failed to operate, or when for any reason it is desired to manually control the position of the valve P.

In another application, of even date here with, Serial No. 186,003, a special form of electromagnetic valve, such as it is preferred to employ for controlling the inlet and outlet pipes, is described and claimed; but it is evident that various forms of valves operated electro magnetically might be substituted therefor in this organization.

Each of those shown herein consists of the electromagnet V, Fig. 4, the back piece, o, of which is preferably heavier than is usual in electro-magnets. This back piece forms a suitable support for the valve-seat. Thearmature c is attached to a rod, oflwhich is adj ustable by means of two nuts,'v and U5. Aspring, o presses at one end against the back piece of the magnet and at the other against an adjustable screw, 1), upon the rod v and tends to hold the armature away from the magnet.

Then the magnet is vitalized the armature is drawn forward against the tension of the its magnet the valve is drawn against the seat,

closing the opening, and when the magnet is vitalized the valve is depressed, and thus the opening into the corresponding pipeis formed.

For the purpose of testing the condition of the line and of the apparatus at any time, at or near the supply source of the system, a switch, S, (see Fig. 5,) is employed. By means of this the circuit of the local battery 0 may be closed, either through the magnet K or K and thus the corresponding valve may be operated independently of the transmitting apparatus. One of the contact-points, s, of the switch is connected with the conductor 9, leading from the contact-point f to the electro-magnet K, and the otherpoint, s, is connected wit-h the conductor 10, leading from the point f to the electro-magnet K. The switch-leversis connected by the conductor 17 with the battery O,and it is evident that a circuit may be established thereby through either electro-magnet. \Vhen, there fore, either valve has been thus operated by the switch S, the pressure in the main may be increased or decreased, as desired, and this will cause the pressure at the distant point to be correspondingly changed, so that if the apparatus is in operative condition it will immediately respond to the abnormal increase or decrease of pressure and cause a correspond- J The poing current to be sent over the line. larized relay will then be operatedin the manner already described. By the contact of its lever with one point or the other thelocal circuit will be closed through the other electromagnet from thatwhich is placed in circuit by the switch S, and thus the remaining valve will be automatically opened. This imme diately causes the balanced valve P, which controls the supply, to be adjusted.

For the purpose of insuring that the pressure shall remain approximately correct, even should. the circuit-conlrolling apparatus at the distant point become for any reason inoperative,a gage, T, Figs. 3 and 5, is employed. The indicating-arm tot this gage moves over a dial, t. hen the apparatus is adjusted, the point at which this indicatingarm should stand, in order to give the required pressure at the distaut point, may be noted upon the scale. Two

v adjustable contact-points, t and i, are placed just outside the limits, which correspond to dicating-arm t is electrically connected by a conductor, 18, with the conductor 12, leading from the battery 0. The contact-points t and t are connected by conductors 15 and 16 with the conductors 9 and 10, respectively leading from the relay contact-pointsf and f to the valvecontrolling magnets K and K In this manner the contact of the-indicatort of the arch-gage with either one or the other ofits contact-points will cause a circuit to be completed through the magnet, which should be properly vitalized by the contact of the polarized relayarmature with one or the other of its contacts. Preferably the position of the two contactarms t and t are such as to allow somewhat greater limit of variation in pressure than that for which the circuit-controller at the distant point is adjusted.

In Fig. 6 a modification is illustrated, by means of which the variations of the limits of the movement of the pole-changer may be governed from a distant pointas, for instance, from the supply-station. The position of the frame 1) is modified by the cam (Z and its adjusting-train, but the movements of the cam are controlled by the electro-magnet D, instead of by a constantly-moving train. It is designed that a disk, d", containing a single tooth, (1 shall be carried upon the arbor of a wheel of the train. to the tooth d", and upon the axis of the anchor there is carried a lever, (P, supporting an armature, d, which is applied to the electromagnet. A spring, d, normally holds one arm of the lever d against a contact, d, and j the armature away from its electro-magnet, and at the same time one of the pallets d is held in position to engage the tooth d". \Vhen the electro-magnet is vitalized the lever is drawn from the contact (1 and its other arm strikes a contact, (1 At the same time the tooth d is released from the pallet d and the disk is drawn forward by the train until it isarrested by the pallet d.

The main line L is connected through the frame-work with the lever (1 The contactpoint (1 is connected by conductors 21 and 22 through the coils of the eleetro-maguet D, and thence by a conductor, 23, with the earth. The magnet offers, approximately, nine times the resistance that the line offers. A conductor, 25, including a signaling -bell, ,H, leads from one pole of the battery 0 to a-switchpoint, 3*, of a switch, S, connected with the main line. The point 5- of this switch is connected through the relay F with the earth.

\Vhen the switch S is moved to the contact 8 the magnet K is vitalized and the corresponding magnetic valve is operated, which,

by introducing air above the piston n, tends to open the balanced valve P. The pressure An anchor, d is applied at the distant point will thus be increased,x

causing the points I) and b torest on their corresponding contact-surfaces, c and c". The usual signal will thereupon be given by the hell H, the relay-arm f will strike the contact f, which will open the other magnetic valve,

and thus the piston a will be held in equilibrium.

Nine-tenths of the current from the battery 0 will flow through conductors 20 and 21, point (1, lever (2 frame of the clock-train to line, thence through switch S, point 3, bell H, and coils of the relay to the ground at G. One-tenth of the current will escape from conductor 20, through the conductor 22, magnet D, and conductor to earth. This current is not sufficient to vitalize the magnet- D and attract the armature c 7 If, now, the switch S be moved to the point 8, the connections of the line with the earth at G will be broken, causing all the current from the battery 0 to traverse the conductors 20 and 22, the magnet D, conductor 23, and thus to the earth. This will vitalize the magnet sufiiciently to attract the armature d bringing the lever (1 into contact with the point (2 At the same time this movement releases the pallet d from the tooth (Z which immediately moves forward until it is caught by the pallet (2*. At the same time the cam d raises the frame D, and thus gives the required alteration in pressure. The current from the battery 0 will traverse conductor 25, bell H, point S, switch S to line, thence through the frame of gears, lever (1 point (2, and conductor 24 to earth. XVhen the signal on bell H has sounded, the switch S is removed from point 5* to s. The switch S is then removed from the point a to the point s". This will close valve M and open the valve M whereupon the piston a will immediately rise, closing the balanced valve P. This will decrease the pressure at the distant point, breaking the contacts b and b. The armature d will thus be released and restore the lever d to its contact-point (1, releasing the tooth d from the pallet d", thus permitting the disk to revolve until arrested by the pallet (1. Meanwhile the pressure decreases until contact is made between the points 6 and b and contact-surfaces c and c whereupon nine tenths of the current will again flow through the line, giving the signal upon the bell H and operating the relay which opens the other valve. The switch S is now removed from point 8'' to a central position, and the polechanger or circuit-controller ad justs the valve 1? to the altered pressure. To increase the pressure, a similar operation is performed.

The invention has been described in its application to gas-mains; but it is evident that it may be applied to the controlling of other pressures and other varying forces. This particular organization is especially designed to be employed for low pressures. In another application of even date, Serial No. 186,002, there is described an organization especially adapted to control high pressures.

I claim as my invention- 1. The combination, substantially as hereinbefore set forth, of a device responding'to variations in force, a circuit-controller operated by said device, a main line over which currents may be sent in one direction or the other by said circuit-controller, accordingly as said force varies in one direction or the other, two valves, one or the other of which may be operated accordingly as a current is sent in one direction or the opposite, a valve-controlling apparatus for modifying the force exerted upon said device, and means for operating said valvecontrolling apparatus through the instrumentality of the first-named valves.

2. The combination, substantially as hereinbefore set forth, with a device responding to variations in a force, of a circuit-controller, a main line over which currents are sent in one direction or the other by the operation of said circuit controller, a relay included in said line, a pressure-controlling device, a valve for controlling the operation of the last-named device, and intermediate devices operated through the instrumentalit-y of said relay for controlling said valve.

3. The combination, substantially as hereinbefore set forth, of a gas-main, a current-reversing circuit-controller responding to variations in the pressure in the main, a supplyvalve for controlling the pressure, an electromagnetic device operated by currents transmitted through the instrumentality of said circuit-controller, two valves, one or the other of which is operated by said electromagnetic device, according to the character of the currents transmitted by said circuit-controller, and means controlled by the last-named valves for opening and closing said supply-valve.

4. The combination, substantially as hereinbefore set forth, of a gas-main, a circuit-controller responding to variations in the pressure of the main, a supply-valve for controlling the pressure, a relay operated by currents transmitted through the instrumentality of said circuitcontroller, and two valves, one or the other of which is operated by electromagnetic devices, accordingly as said relay is vita-lized by a positive or a negative current, and means controlled thereby for opening and closing said supply-valve.

5. The combination, substantially as hereinbefore set forth, with a device rising and falling with the variations in pressure, of contactsprings carried thereby, corresponding contactsurfaces insulated from each other, respectively extending below and above the corresponding springs, substantially as de scribed, means for adjusting the positions of said points at will, aclock-train, and a device operated thereby for automatically adjusting the position of said contact-points.

6. The combination, substantially as hereinbefore set forth, with a device rising and falling with the variations in a force, of four contact-springs carried thereby, four corresponding contact-surfaces insulated from each other, two extending below and two above the corresponding springs, substantially as described, and independently adjustable supports for said points.

7 The combination, substantialiy as hereintact-springs carried thereby, four corresponding contact-surfaces insulated from each other, two extending below and two above the corresponding springs, substantially as described, means for adjusting the position of said points at will, a main line, a polarized relay in cluded therein, a local battery, a valve, and two electromagnetic valve-controlling devices respectively included in circuits of said local battery closed by said relay.

8. The combination, substantially as hereinbefore set forth, with a device responding to variations in a force, of a current-reversing circuit-controlling device, a main line over which said circuit-controlling device serves to transmit electric currents in opposite directions, an electromagnetic device responding to said currents, two electromagnetic valves, one or the other of which may be operated according to the operation of said circuitcontroller, an equilibrium valve, and means for varying the pressure exerted upon one side of the last-named valve through the action of said electromagnetic valves.

9. The combination, substantially as hereinbefore set forth, with a pipe, of a valve for opening and closing the same, an air-chamber connected with the pipe leading from said valve, a piston within said chamber, connected with said valve, for opening and closing it, which piston rises and falls with variations in the pressure in said pipe, a circuit-controller operated by said piston, and inlet and outlet valves for governing the resultant pressure upon the said piston.

10. The combination, substantially as hereinbefore set forth, of a gas-main, a gas supply, a valve for controlling the flow of gas from the latter to the former, an air-tight chamber communicating with the gas-inain, a piston within the same, a connection between said piston and said valve, an air-chamber above said piston, a source of fluid-pressure, a pipe leading therefrom to thelast-nan1ed air-ehamber,a circuit-controller operated by said piston, an electromagnetic device for controlling the inletopening through said pipe, an outlet-opening from said chamber, an electromagnetic device for controlling the opening through'the latter, and circuit-connections from said circuit-controller through said electro-magnetic devices.

11. The combination, substantially as hereinbefore set forth, of a device responding to variations in a force, a circuit-controlling device for completing the connections of an electric circuit when said force exceeds or falls below predeterminedlimits, and means for modifying said limits, consisting of a clock-work, an escapement for controlling the movements of the same, a mechanical. connection between said clock-work and the contact-points of said circuit-controlling device, an electromagnet for controlling the operation of said escapement, and means, substantially such as de scribed, for completing electric connections through said electro-magnet.

12. In a device for controlling the expenditure of a variable force, the circuit controller, a mechanical device for adjusting the circuitcontroller, a battery, an electromagnet, a main line, means for completing the circuit of the battery through the magnet, a branch circuit around the magnet and through the main line of less resistance, means for interrupting the connections of the main line, and thereby vitalizing said magnet and operating said mechanical device, and means, substantially such as described, for subsequently automatically interrupting the circuit through said magnet.

In testimony whereof I have hereunto subscribed my name this 1st day of December, A. D. 1885.

lillLTOh XV. GROVESTEEN. Witnesses:

CAROLINE E. Davrnsox, CHARLES A. TERRY.

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