US570042A - Valve mechanism for steam-pumps - Google Patents

Description

-8 Sheets-Sheet 1.

(No Modem :J. L; M GIPPIN. v .VALVE MBGHANISM FOR STEAM PUMPS.

Patented Oct. 27, 1896.

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(No Model,) 3 Sheets-Sheet 2. J. L. MGGIPPIN. VALVE MECHANISM FOR STEAM PUMPS.

I No. 570,042.

Patented Oct. 27,1896.

(No Model.) 3 SheetsSheet 3. .J. L. McGIF-FIN.

VALVE MEGHANISM'FOR STEAM PUMPS.

UNITED STATES PATENT Err-(1E.

JOHN'L. MCGIFFIN, OF SCOTTDALE, PENNSYLVANIA.

VALVE MECHANISM FOR STEAM-PUMPS.

SPECIFICATION forming part of Letters Fatent No. 570,042, dated October 27, 1896.

Application filed February 14, 1895. Serial No. 538,324. N m el-l T0 aZZ whom it may concern..-

Be it known that I, JOHN L. MoGIFFIN, a resident of Scottdale, in the county of \Vestmoreland and State of Pennsylvania, have invented a new and useful Improvement in ValveMechanism for Steam-Pumps; and I do hereby declare the following to be afull, clear,

and exact description thereof.

My invention relates to reciprocating pu mps and to the valve mechanism employed therewith, its object being to simplify the valve mechanism and provide a fluid-operated main piston-valve of peculiar construction, as will be hereinafter more particularly set forth.

It comprises, generally stated, in the combination with a main cylinder and piston, a fluidoperated main piston-valve controlling the cylinder-ports, said valve being of cylindrical form and hollow, and having supplyports extending through its walls and forming communication directly with the cylinder-ports, and-an auxiliary slide-valve'at the side of the main valve and controlling the ports operating the piston-valve, and tappet connections from the piston-rod to the auxiliary valve.

It also comprises other improvements which will be hereinafter set forth and claimed.

To enable others skilled in the art to make and use my invention, I will describe the same more fully, referring to the accompanying drawings, in which- Figure 1 is a longitudinal central section of the pump. Fig. 2 is an enlarged central horizontal section of the steam-chest. Fig. 3 is an enlarged longitudinal vertical section of the steam-cylinder and steam-chest. Fig. 4 is a longitudinal vertical section of the auxiliary valve-chamber. Fig. 5 is a central cross-section through the steam-cylinder and steam-chest. Fig. 6 is a detail cross-section 011 the line 6 6, Fig. 4. Fig. 7 is a cross-section on the line 7 7, Fig. 1. Fig. 8 is a perspective sectional view of a main slide-valve. Fig. 9 is a perspective sectional view of the auxiliary valve, and Fig. 10 is a detail section showing the joint between the piston-rod sections.

Like letters of reference indicate like parts in each.

The steam-pu mp in its general construction has the steam-cylinder A, the piston B, the pumping-cylinder C, and the piston-rod 1), connecting the pistons B and D. The pump is illustrated with the ordinary valve construction for the inflow and outflow of the Water or other fluid to be pumped, and as the invention does not relate to this part it will require no further description.

The engine portion of the pump is formed of two main castings, the cylinder-casting A, having the fiat upper face a, and the steamchest casting E, having a fiat under face which rests on the steam-chest casting, the two castings being bolted together. The cylinder-casting A has the main ports 0 cl leading from the cylinder-chamber A", and these ports also extend through the steam-chest casting E, opening into the base of the cylindrical main-valve chamber F, in which the cylindrical main valve G slides. The steamchest casting E has the auxiliary-valve cham ber H at the side of the main-valve chamber F, the base of which is formed by the flat top face a of the cylinder-casting, and said flat top face also forms the valve-seat h for the auxiliary valve h, such general construction simplifying and cheapening the engine.

The engine-port c has the main port 0', which is placed some distance from the end of the cylinder-chamber A, and the cushioning-port 0 close to the end of the cylinderchamber, and the port cl has like ports d 01 The usual central main exhaust-port e is employed, which leads fronrthe cylindrical valve-chamber F, through the steam-chest E and cylindrical casting A, to the escapeport 6.

I will first describe the general construction' of the main-valve chamber F and its valve G. The main-valve'chambcr is preferably a cylindrical chamber and of the same diameter throughout, and it has the inletport f, leading centrally into the top of the chamber, and the ports 0 d (2, above referred to, leading therefrom through the body of the valve chest and communicating with like ports, similarly lettered, in the main cylinder, as above stated. It has also one or more ports 71-, forming direct communication with theauxiliary-valve chamber H, and on the opposite side thereof is formed the bearing f, through which the shaft f carrying the starting-lever f, passes, said starting-lever being employed as a precaution, though not generally necessary, as the pump is found to operate positively and to start, no matter what the position of its valves or pistons, even at a very low pressure. The main slidevalve G, the construction of which is illusstrated in the different views and is more clearly shown in the perspective view of Fig. 7, corresponds in shape to the valve-chamber f, being preferably cylindrical, as above stated, and of the same diameter throughout, and it may have suitable packing-rings fitting around the same to pack it within the valve-chamber. The valve Gis made hollow, having the solid end walls g, and in the central port-ion thereof having the passage or opening 9 to permit the entrance of steam from the inletport f, having the side passage on the side through which the shaft f passes and having the side passage g on the other side, which provides for the passage of steam to the auxiliary chamber H through the port or ports 7L2. It also has the pillars or posts 6, against which the starting-lever f operates. As so constructed it has the hollow chambers 7,; 7t, one at each end, and a central hollow portion k steam passing from the same around the pillars 1' into the hollow chambers 7,1. The valve has also the supply-ports m m, leading from the chambers 7c 7r through the walls of the valve, which form direct communication between the interior of the valve and the engine-ports c (1, respectively, so that no separate slide-valve controlling said ports is required, and on account of the cylindrical body of the valve-chest and the cylindrical slide-valve working therein close and perfect joints which are not liable to wear are formed between the supply-ports and the cylinder-ports. Formed in the bottom face of the valve G is the groove or recess n, which forms the exhaust-passage between the cylinder-ports e (Z and the exhaustport 6. As so constructed a very simple form of valve is obtained, which can be cheaply made and is not liable to wear and which serves both the purpose of the main slidevalve controlling the main ports and the piston-valve to operate the same.

The auxiliary-valve chamber II is located at the side of the main-valve chamber directly above the outlet-port e, where it passes through the main-cylinder casting, and the top face of the cylii'ider-casting A forms the base of the chamber and the seat a for the valve. It has the central exhaust-port Z, leading through the cylinder-casting A to the outlet-port c. It has also the ports 1) 1), lead in g down into the cylinder-casting to one side of the valve-seat and thence up to the under face of the valve-chest and, as shown in dotted lines in Fig. 7, to the main-valve cylinder F, said ports 1) 1) opening by small passages, as indicated in Fig. 3, into the ends of said cylinder, and openinga sufficient distance from the ends of the cylinder to provide for the cushioning of the main slidevalve therein. The auxiliary valve h has the central recess Z, forming the exhaust-passage between the ports 1) p and the exhaustport Z. It is to be noticed that the auxiliary valve is of such length that it always covers the ports 1) and to form communication therewith near the ends thereof the ports 4' 0- pass directly through the body of the valve for the passage of steam to the ports 1) p, respectively. The valve h is operated by the tappet-rod g, which has 'the tappet q thereon, the valx'e it having the lugs g g extending up therefrom and recessed to receive the tappet-rod (1 and the tappet q, moving between such lugs (f (f and near the ends of the stroke of said rod striking against the standards, so causing the movement of the valve over the ports I, p, and 1'). Any suit able mechanism for operating the tappet-rod q may be employed, that illustrated in the drawings, and which is preferred by me, being the arm 8, carried by the piston-rod Z) and depending below the same and having a pin .9 and carrying a sliding block .9 working in a slide 6 in the lower end of the lever t. This leveris secured to a shaft t mounted in a bearing a on the horizontal brace or bar it, extending between the steam-eylinder A and the pump-cylinder O, and extending up wardly from the other end of the shaft t is the lever i which forms an extension of the lever t and is connected to the rod or strap 'U, the other end of which connects to the tap pet-rod q. The strap 1; is preferably made of a flexible bar to provide for the necessary defleetion of the end thereof connected to the lever t in the swinging of the lever.

In order to simplify the repair of the pump, the piston-rod Z) is formed in two sections Z) 11 so that either piston or cylinder may be removed without disturbing the other. I employ any suitable joint for connecting the sections and have illustrated it as made by the clamp s, securing the arm 3 to the pistonrod. The adjoining ends of the rod-sections l) b are threaded and nut-locks b are first screwed thereon, after which the collars Z), having flanges l), are screwed onto the rods. The clamp s has a recess .9 to receive the flanges Z), and the cap .9 of the clamp has a like recess and fits over the collars b and is bolted to the body of the clamp, after which the nut-locks may be screwed up against the clamp, the collars I)" and nuts providing for accurate adjustment of the rod-sections. To remove or repair either cylinder or piston, it is only necessary to open the clamp, so dividing the piston-rod into two sections and providing for easy handling.

In the operation of the pump the steampiston B reciprocates in the cylinder A, and thus the piston-rod 1) moves the piston D on the cylinder 0, so operating the pumping mechanism. The steam entering the steamchest and entering the valve chamber F through the port f flows into the valve-chamber H through the port or ports 7L2. In the reciprocating stroke of the piston rod 1), through the arm 5 and its sliding block .9 workin g in the guideway 25 in the tappet-lever 2 the tappet-rod q is caused to reciprocate, and in its movement the tappet or block q on said rod contacts with the lugs g and g on the auxiliary valve h when the tappet approaches the end of the stroke, and so draws the ports 1* 1" into and out of communication with the ports 1) p and forms communication between the exhaust-port land said ports 19 p through the recess or groove Z. It will be noticed that the ports 0' r in the valve it pass directly through the same and are small in area, the purpose of such construction being to admit a small inflow of steam from the chamber 11 to the ports 19 p and to provide for the quick cutting off of the same. These ports are so located in the valve h as to give the desired lead or stroke to the main-piston valve G, so as to enable it to properly control the ports leading to the main cylinder. The steam passes through the ports or passages 19 p to the respective ends of the valve-cylinder F, entering the same at the points more clearly shown in Figs. 2 and 3. Supposing that the main piston B occupies the position shown in Fig. 3, the engine-cylinder receiving steam through the port m of the valve G and through the port or passage (1, the steam will first pass through the port (1 to that end of the main cylinder A which Will cause the movement of the piston until it uncovers the larger supply-port (Z, and the piston will then travel toward the other end of the cylinder, carrying with it the arm 5 on the piston-rod and causing the swinging of the tappet-lever t and at the same time the movement of the tappet g, which, before the end of the stroke,

strikes a ainst the 111 c of the valve h and e a 1 slides the valve from the position shown in full lines to the position shown in dotted lines in Fig. 4, closing communication between the ports 1' and p and opening communication between the ports 1' and p and between the port 1) and the exhaust-port Z. Steam will then pass through the port 13 to the forward end of the valve-cylinder F and be exhausted from the rear end thereof through the port 19, which causes the movement of the valve G, closing communication between the port m, leading through that valve and the maincylinder port d, and moving the valve so that the valve-port m is brought into communication with the main-cylinder port 0, while the groove or recess a is moved so as to close communication between the ports 0 and e and open communication between the ports d and e. The steam then passes from the interior of the main-piston valve G and through its port m into the cylinder port or passage 0, and is exhausted from the other end of the cylinder through the ports or passages 01 e, causing the moving of the piston 13 in the opposite direction, the main-piston valve remaining in the position shown in Fig. 1. As the tappet-lever t is swung in the opposite direction by the arm 8 on the piston-rod it moves the tappet g, which toward the end of its stroke strikes the lug g on the valve 71, moving it to the position shown in Fig. 4, so that steam passes through the port 19 to the outer end of the valve-cylinder F and is exhausted through the port 19 from the opposite end thereof, which causes the return movement of the cylinder-valve G, bringing it to the position shown in Fig. 3, and bringing the port m in line with the cylinder-port cl and forming communication between the cylinder-port c and the exhaust-port e. In these operations the valve mechanism is arranged to give the necessary lead to the different valves, so as to control the movement of the main piston and prevent its striking the cylinder-head, and it will be noticed that the main valve G closes the cylinder-ports as the main piston approaches the ends of the main cylinder, so providing for the cushioning of the same. It will also be noticed that a like means for cushioning the cylindervalve G is provided, as the ports 19 19 enter the valve-cylinder some little distance from the ends thereof. The main-cylinder valve G thus acts itself to control the main-cylinder ports without the interposing of any separate slide-valve, and this is accomplished by the employment of the hollow valve having ports therein adapted to coincide with the cylinder-ports and having the peculiar construction shown, with the top opening in the central part thereof to permit the steam to enter the hollow valve. As a 'matter of fact the engine consists of the main cylinder A, formed in one casting, and the steam-chest formed in another casting. In this way the valve-chest need not be larger than the size of the single main valve and the auxiliary valve at the side thereof, which requires very little increase in the size of the casting. The top face of the main-cylinder casting is utilized to close the auxiliary-valve chamber and form a seat therefor, while the exhaust-port controlled by the auxiliary valve opens directly into the main exhaust-port and can be formed by a simple core in the casting. The different ports can also be formed at but small expense and be formed in the exposed parts of the'castings, to form communication between the tappet-valve and the main-cylinder valve.

Practical use has shown that the pump can be operated at any desired speed, from an exceedingly slow to a very rapid stroke; that it can be stopped and started in any position and is positive in its action, starting on a very low pressure of steam at a slow stroke as easily as under high pressure.

WVhat I claim as my invention, and desire to secure by Letters Patent, is

1. The combination with a main cylinder formed of a casting having a flat upper face, asteam-chest formed of a separate casting and having a main-valve chamber containing a steam-operated valve, main-cylinder ports being formed in both of said castings and controlled by ports in the steam'operated valve, said steam-chest having at the side of the main-valve chamber an auxiliary-valve chamber, containing a tappet-valve having its valve-seat formed on the top face of the main-cylinder casting and tappet connections from the piston-rod to said tappet-valve, substantially as set forth. I

2. The combination with a main cylinder and steam-chest having a main-valve chamber, a steam-port communicating with the upper end of the valve-chamber, and a fluidoperated main-piston valve, said valve being formed hollow and having an opening in the upper part of the central portion thereof to permit of the entrance of steam and having supply-ports leading through the lower portion thereof forming communication with the cylinder-ports, substantially as set forth.

3. I11 steam -engine -valve apparatus, the combination with a steam-chest having a cylindrical valve-chamber with which the inletport f and with which the cylinder-ports e, (Z, c, communicate, and the fluid-operated hollow cylindrical valve G having the central opening g communicating with the inlet-port f, the hollow chambers 7t, 7t and supply-ports m m passing through the same and forming direct communication with the cylindenports c, (I, and the recess n, in the under face communicating with the main exhaust-port, the valve having also the central side opening 9 and the pillars 2', and the startingdeverf supported between said pillars on the shaft f entering through the opening g on the same horizontal plane as the valve G, substantially as set forth.

4. In the combination with amain cylinder formed of a casting havinga flat face, a valvechcst having a main cylindrical valve-chamber with an inletport entering cent ally through the top thereof, an auxiliary-valve chamber at the side of the main chamber, and having the auxiliary valve seated on the top face of the main-cylinder casting, one or more ports in the wall between the valvechambers and a hollow cylindrical valve fitting in the main-valve chamber, and having a central opening communicating with the inlet-port and an opening in the side providing for communication with the auxiliary valve chamber, through said port or ports, substantially as set forth.

5. In combination with a main cylinder formed of acasting with a Hat upper surface, a valve-chest formed of a separate casting resting thereon and containing a 1nainvalve chamber and an auxiliary-valve chamber at the side thereof containing a slide-valve seated in the upper face of the main-cylinder casting, and ports leading from the seat of said auxiliary valve down into the main-cylinder casting and thence to the under face of the valve-chest casting and to the end of the main-valve chamber, substantially as set forth.

0. In steamengine valve apparatus, the combination of a valvechest having the valve-chamber H with ports 1.), p and Ztherein, a slide-valve 72 having the central exhaustrecess Z and supply-ports r, 7' formed of holes passing directly through the body of the slide-valve, and having the lugs q" and the tappet-rod having a tappet operatingbctween said lugs, substantially as set forth.

7. The combination with a main cylinder having a piston sliding therein, of a valvcchest having the valvechamber ll. and the tappetyalve h therein, the depending arm s having a sliding connection with the lever Z, the tappet'rod q and connections between said lever and the tappet-rod q, and a tappet on the rod engaging with the valve, substantially as set forth.

8. The combination with a main cylinder having a piston sliding therein, of a valvechest having the valve-chamber II and the tappet-valve h therein, the arm 5 having a sliding connection with the lever t, the tappet-rod q and a flexible strap connecting said 9 lever and tappet-rod, and a tappet on the rod engaging with the valve, substantially as set forth.

9. The combination, in a steam-operated apparatus, of valves or pistons in line with each other and a rod connecting the valves or pistons, said rod being made in two sections and flanged collars secured at the ends of the rod-sections, and a clamp fitting around said flanged collars, substantially as set forth.

In testimony whereof I, the said JOHN L. MCGIFFIN, have hereunto set my hand.

JOHN L. MCGIFFIN. \Vitnesses:

ROBERT 0. Terms, LINDSAY on B. LITTLE.

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