US329202A - Stuffing-box - Google Patents

Description

(No Model.)

T.MURPHY.L

STUFFING BOX. I No. 329,202. Patented 002.27, 1885.

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THOMAS MURPHY, or DETROIT, MICHIGAN.

STUFFlNG-BOX.

SPECIFICATION forming part of Letters Patent No. 329,202, dated October 27,1885.

Application filed March 18, 1885.

To all whom it may concern.-

Be it known that I, THOMAS MURPHY, of Detroit, in the county of Wayne and State of Michigan, have invented new and useful Improvements in Stuffing-Boxes; and I do hereby declare that the following. is a full, clear, and exact description thereof, reference being had to the accompanying drawings,which form a part of this specification.

This invention relates to new and useful improvements in stuffing-boxes for pistonrods, and the improvement is mainly designed for use in connection with such verticallyoperating piston-rods which are subject to marked vibrations, all as more fully hereinafter described.

In the drawings which accompany this specification, Figure 1 is a part of a vertical central section of a compound steam-engine of that class commonly called steeple-engines, and showing my improved stuffing-box applied to the piston-rod in the intermediate head between the two cylinders. Fig. 2 is an enlarged and detached section of my improved stuffingbox.

A is the small and B the large cylinder of a compound vertical steam-engine,-having a piston-rod 0, intermediate head, D, and stuff ing-box E, all arranged in the usual manner.

The construction of my improved stuffingbox is as follows:

F is a cylindrical sleeve, preferably of brass, and provided with a ground shoulder, a, near its lower end, by means of which it is seated steam-tight upon the circular flange b of the stuffing-box. The diameter of this sleeve is smaller than the bore of the stuffing-box, so as to allow it a slight lateral play. The lower portion of this sleeve is nicely fitted upon the piston-rod, while its upper portion is bored out conically to form a seat for a series of conical packing-rings, G. These packing-rings are of suitable anti-friction metal,such as Babbitt, and each ring is divided into two or more segments. v

H is a follower placed on top of the packing-rings. It is preferably of brass, and is fitted upon the piston-rod. Its diameter is sufficiently smaller than the bore of the stuffing-box to allow it the same play as the sleeve F.

Serial No. 159,333. (No model.)

L is a retaining-plate on top of the follower H. It is secured to the intermediate head, and its object is to retain the sleeve F, packing-rings G, and follower H in position within the stuffing-box, without exerting, however, any pressure upon them, it being essential to preserve to these parts freedom to play laterally under the action of the vibrations of the piston-rod.

It is a well-known fact that the vibrations of piston-rods in vertical steam-engines are more marked than in horizontal engines, and as these vibrations depend upon the length of the piston-rod it is clear that in engines of the kind shown in the drawings they become a factor with which ihe constructing engineer has to deal. As the vibrations of a piston-rod are always largest in the center, it is (with engines of the kind shown) the stuffing-box in the intermediate head which is most affected by them, and in the same degree as this stuffing-box tends to hold the piston-rod rigidly in line it becomes more unsuitable for this place.

It will be seen that my stuffing-box freely accommodates itself to all the vibrations of the piston-rod, while at the same time it forms a steam-tight joint, so essential in this class of engines. At the downward stroke of the piston-rod the weight of the sleeve, packingrings, and follower, supplemented by the frictional adherence of these parts to the pistonrod, will firmly hold the shoulder a of the sleeve upon its seat and press the packingrings into their seat and around the piston-rod, thus forming a steam-tight joint in the stuffing-box. At the upward stroke of the pistonrod the parts of the stuffing-box operate in the same manner, the frictional adherence of the parts to the piston-rod (which acts now inversely) being counteracted in this instance by the larger pressure of the steam in the cylinder A, which presses upon the follower.

I preferably provide the sleeve F with a small shoulder, 0, upon which the lowest one of the packing-rings is seated. This shoulder helps hold the packing-rings in position, and if made small enough does not prevent them from adjusting themselves to the piston-rod, as sufficient experience has demonstrated that the lower edge of the packing-ring seated on the shoulder a will wear away fast enough to allow the packing-rings to adjust themselves to compensate for wear.

Although my stuffing-box is devised for a special purpose, I do not want to be under stood as limiting its adaptability to the special application shown and described above, as the conditions under which it will operate are found in all vertical engines.

The obj ect of the follower H is to more evenly distribute the pressure upon the packingrings. It may be dispensed with, however, in which case the uppermost packingring would act as a follower.

I deem it important that the follower H fit closely to the piston-rod and extend to the exterior of the stuffing box to bear against the retaining-plate upon two surfaces at right angles to each other.

What I claim as new is- 1. In a stuffing box, the combination, with the sleeve I conical] y recessed at one end and having a shoulder, a, near the other, of the conical packing-rings G, fitting within the conical recess of the said sleeve, and a follower, as H, these parts having free lateral play in the stuifing-box, and the sleeve and follower having cylindrical necks which extend to the exterior of said stuffing-box, as set forth.

2. In a stuffing-box, the combination, with the sleeve F, having a shoulder, a, near one end and a conical recess near the other, terminating in ZL SIDZLll shoulder, a, of the conical packing-rings G and the follower II, all arranged and confined within the stuffing-box so as to have a free lateral play therein, substantially as and for the purpose described.

TIIOS. MURPHY.

Witnesses:

H. SPRAGUE, E. J. ScULLY.

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