US858088A - Apparatus for maintaining uniform pressure. - Google Patents

Description

No. 858,088. PATENTED JUNE 25, 1907.-

' W. B. MASON.

APPARATUS FOR MAINTAINING UNIFORM PRESSURE.

APPLICATION FILED MAY 16. 1906.

Z SHBETSSHEET 1.

Fay.

witnezsaz- 1%1/6 Ywak PATENTED JUNE 25, 1907.

W. B. MASON.

APPARATUS FOR MAINTAINING UNIFORM PRESSURE.

APPLIOATION FILED MAY 18. 1906.

2 snnmssnnm 2.

2.91 Fay. 6?.

[flimsy Z5714 iafn J asses:

THE NORRIS PETERS C0,, wAsHmm-au, n, r:v

IINITED STATES PATENT OFFICE.

WILLIAM B. MASON, OF BOSTON, MASsAoHUSETTS, ASSIGNORTO THE MASON REGULATOR COMPANY, OF SACO, MAINE, A CORPORATION OF MAINE.

APPARATUS FOR MAINTAINING UNIFORM PRESSURE.

Specification of Letters Patent.

Patented June 25, 1907.

Application filed May 16, 1906. Serial No- 317,106.

' of which the following is a specification, reference being had therein to the accompanying drawings.

It is fre uently the case that driers and other simi ar devices are required to be heated at a constant pressure by steam from a source of steam supply which is itself variable in pressure, as, for instance, the exhaust steam from an engine.

My invention is applicable to any chamber which is heated from a variable source of steam supply, and in which it is desired to maintain uniform pressure. In the case of a paper drier, which is heated by the exhaust steam from an engine, and in which it is desired to maintain a uniform pressure of perhaps five pounds by means of steam from an exhaust pipe which ordinarily has a pressure of six or seven pounds, it will be found that it is necessary to vent the exhaust pipe or the chamber to the atmosphere to permit the escape of a sufficient portion of the steam from the exhaust to prevent the pressure in the drier or chamber rising above the predetermined point. On the other hand, it will also probably be found that on certain occasions the pressure in the exhaust pipe will fall below the predetermined pressure for the drier or chamber, and that consequently it is desirable that steam at a greater pressure be introduced into the said drier or chamber to raise the pressure to the predetermined point. This is best accomplished by introducing live steam into the chamber directly from the boiler.

My invention has for its object a device or system for controlling automatically the venting of the steam from the chamber when the pressure rises too high and the admission of the steam to the chamber when the pressure falls too low.

The invention affords a simple mechanism which is controlled by the pressure in the chamber and which maintains the said pressure at substantially the predetermined point by means of the occasional operation of the valves controlling the-vent to the atmosphere and the inlet of steam from the boiler.

I believe my invention to be a broad one and to be susceptible of being embodied in a considerable variety of forms.

For convenience I havedescribed the invention in connection with the supply of steam to a number of chambers where the amount of steam required is large, and accordingly where the steam pipes and various valves are of large size, so that it is inconvenient or impossible to carry the pipes to a board or panel, it being necessary that the valves be located at points determined by the locations of the steam pipes. This is one form in which I put the invention into actual operation, but I desire not to be limited to this form as my invention is a broad one and capable of a variety of applications and embodiinents.

The invention will be fully understood from the following specification taken in con nection with the accompanying drawings, and the novel features thereof are pointed out and clearly defined in the claims at the close of the specification.

Referring to the drawings,-Figure 1 is a diagrammatic view of the device embodying my invention. Fig. 2 is a section of the fluid pressure actuated device which Operates the valves. Fig. 3 is a vertical section showing the interior construction of the high pressure valve.

Referring now to the drawings, and particularly to Fig. 1, at A is indicated the ex haust pipe of an engine which supplies steam through various connections to chambers or driers not shown, to each of which leads one of the small pipes B.

At 0 is shown the vent to the atmosphere cont-rolled by the vent valve D as will be later described. This valve D is opened at various times when the pressure in the chamber rises above the predetermined point. When the pressure in the chambers falls below said predeterminedpoint, steam from a boiler, not shown, is admitted through the live steam pipe E and the admission of this steam. is controlled by the high pressure valve F.

The interior construction of the vent valve D and the high pressure valve F is illustrated in Fig. 3, which shows the interior of the high pressure valve F in section. The two valves D and F are exactly alike in construction except for the arrangement of their valve levers. The valve F is operated by means of a lever 10 pivoted at 11 to a movable fulcrum 12 which is itself pivoted at 13 to a fixed portion of the frame or casing of the valve. The valve lever 10 is pivoted to the valve spindle 14 at 15, and its end extends beyond the said point of connection with the said valve spindle 14 and enters a slot 16 (see Fig. 1) in an arm 17 which is fixed to and extends upwardly from the frame or casing of the valve. This arrangement serves to guide the valve lever. The valve is opened by the downward movement of the right hand end of the lever 10.

In the case of the vent valve D, the posi tions of the parts are reversed so that the valve is closed by the downward movement of its lever arm 18. In the valve D the lever arm 18 is pivoted at 19 to the valve spindle 20, and at 21 to the movable fulcrum 22 which in this case is on the opposite side of the valve spindle so that the action of the valve lever is reversed. The valve lever 18 is also guided in the slot 23 in the upwardly extending arm 24, which is fixed to the frame or casing of the valve. These valves are preferably balanced piston valves as seen in Fig. 3 where the two valve seats are desig nated 25 and 26. Both the u per valve 27 and the lower member 28 are slightly beveled so that the valve opens gradually.

The pressure weighing device now to be described is of any suitable character and is movable in response to changes in ressure in the drying chamber. Such a evice is shown and described in my Patent No. 561,600, dated June 9, 1896 for a damper regulator. In the following description, I have accordingly thought it necessary to describe the operation of this device only generally and further reference may be had, if desired, to the above mentioned Letters Patent. This pressure weighing device G, which is shown in perspective at the right of Fig. 1 and in section in Fig. 2, operates the vent valve D and the high pressure valve F in the following manner. The pressure weighing device G is connected by a pipe H of suitable size with the chamber in which it is desired to maintain uniform pressure or with the pipe leading thereto as is shown in Fig. 1. The pipe H leads to the diaphragm chamber 29 and the pressure in the said chamber 29, when it rises above or falls below the predetermined oint, moves the lever arm 30 upon which is ocated the adjustable weight 31 which may be moved to vary the predetermined pressure to be maintained in the drier or chamber.

When the ressure in the chamber falls below the prec etermined point, that is, when the exhaust pipe A from the engine is not furnishing sufiicient steam or steam at too pressure supplied from the city mains or other suitable source to be exhausted from the upper side of the piston 36 as explained in my previous patent above referred to. When the piston 36 rises, it permits the chain 45, which is wound up on the rim of a wheel 44; on the outside of the pressure weighing device G, to be unwound.

. The chain 15 is connected to the valve levers 10 and 18 in the following manner. It

passes first over the two sheaves 46 and 47, then about the sheave 48, which is supported in afork or link 49 on the end of the valve lever 10. From there, it passes over a second pair of sheaves 50 and 51, about another sheave 52 similarly mounted on the end of the valve lever 18, and thence to some fixed. point, as the hook 53. The valve lever 10 is provided with the light Weight 54 near the fulcrum 12 while the valve lever 18 is provided with a heavier weight 55 at a greater distance from its fulcrum 22. The high pressure valve F is, therefore, operated more easily than the vent valve D. When the exhaust of Water from the upper side of the piston 36 slackens the chain 15, it will be seen that the valve lever 18 which. operates the vent valve D drops first because its weight is the heaviest, thus closing the vent valve. When the vent valve is closed by this action, the chamber or drier will receive steam at the full pressure of the exhaust. If this is greater than the predetermined pressure, the vent valve will again be opened by the reverse operation of the pressure weighing device to bring the pressure in the chamber down to the predetermined point. If, on the contrary, the full flow of exhaust to the chamber is insufficient to keep the pressure up to the predetermined point, then the vent valve will remain closed, and the continued rise of the iston 36 in the pressure weighing device wil permit the valve lever 10 of the high pressure valve F to sink, thereby opening said high pressure valve F and admitting sufficient steam to the chamber to bring the pressure up to the predetermined point.

When the pressure in the chamber has risen above the predetermined ressure by reason of the opening of the high pressure valve F, the reverse action takes place. The increased pressure in the diaphragm chamber 29 causes the lever 30 to rise and admits water under pressure to the upper side of the piston 36, thus causing the said piston to descend and to wind the chain 45 on the outside wheel 44. As the chain 45 is shortened, it causes the valve F to close first, as that valve is less heavily weighted. If shutting off the flow of live steam wholly or partly by means of the closing of the high pressure valve is not suflicient to cause the pressure in the chamber to fall to the predetermined point, the continued shortening of the chain 45 by the continued downward movement of the piston 36 lifts the vent valve lever 18 and o ens that galve, thus reducing the pressure in t e cham- In actual practice, I find that the amount of steam flowing from the exhaust pipe A is usually more than suflicient to maintain the desired pressure in the chamber. As long as this is the case, the high pressure valve lever 10 will be held in its upper position and the valve kept closed so that the sheave 48 011 the valve lever 10 will then form for the time being a fixed abutment, and the pressure of the steam in the chamber will be controlled entirely by the vent valve which will open slightly to reduce the pressure and close again to increase it. When, however, the steam from the exhaust pipe A is insuflicient to maintain the desired pressure, the high pressure valve will come nto operation and thus the predetermined pressure will be maintained in the chamber under all conditions of the exhaust.

Of course, it is to be understood that any variable source of supply may be employed and any high pressure source of supply may be used to draw u on when additional pressure is required. t is also obvious that the apparatus is equally applicable to all kinds of fluid pressures which require to be used under the conditions herein described.

I claim as my invention:

1. Controlling mechanism for maintaining a constant predetermined pressure in a cham bcr which is connected with two sources of supply, one source being normally of low variable pressure, and the other of high pressure, which comprises a vent valve and a high pressure valve, and operating means for the said valves comprising a pressure weighing device connected with said chamber and movable in response to changes'in pressure therein, and operating to open or to close the said vent valve or the said high pressure valve as may be required to maintain the predetermined pressure in the chamber.

2. Controlling mechanism for maintaining a constant predetermined pressure in a chamber which is connected with two sources of supply, one source being normally of low variable pressure, and the other of high pressure, which comprises a vent valve and a high presmined point and to close the high pressure v valve and open the vent valve -when the pressure in the chamber rises above the said predetermined point.

3. Controlling mechanism for maintaining a constant predetermined pressure in a chamber supplied with fluid pressure from two sources of supply, one of which is variable and the other of which is of relatively high pressure, which comprises a vent valve, an operating lever therefor, a high pressure valve, an operating lever therefor, weights on the said valve levers, the weight on the said vent valve being most effective, and operating means for said valves comprising a pressure weighing device connected with the said chambers andmovable in response to changes 1n pressure therein, and flexible connectlng means between the said operating means and the said valve levers and operating upon the said less effectively weighted lever arm first as the pressure rises and upon the more pflirlectively weighted lever first as the pressure 4. Controlling mechanism for maintaining a constant predetermined pressure in a chamber supplied with fluid pressure from two sources of supply, one of which is variable and the other of which is of relatively high pressure, a vent valve provided with a valve lever fulcrumed to open the said valve as the long arm of the lever rises, a high pressure valve provided with a valve lever fulcrumed to close the said valve as the long arm of the said valve lever rises, weightson the said valve levers, the weight on the said vent valve being most effective, and operating means for said valves comprising a pressure weighing device connected with the said chambers and movable in response to changes in pressure therein, and flexible connecting means between the said operating means and the said valve levers and operating upon the said less effectively weighted lever arm first to close the high pressure valve and open the vent valve when the pressure in the chamber rises above the predetermined point, and to close the vent valve and open the high pressure valve when the pressure in the chamber falls below the predetermined point.

In testimony whereof I aflix my signature, in presence of two witnesses.

WILLIAM B. MASON. Witnesses:

GEORGE P. DIKE, J. HENRY PARKER.

IIO

Images