US1049130A - Vacuum-pump. - Google Patents

Description

A. MORAWSKI.

VACUUM PUMP.

APPLICATION FILED APILG, 1911.

1,049, 1 30, Patented Dec. 31, 1912.

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COLUMBIA PLANOGRAPH CO..WASHINGTON- 1L6v UTTE STATES PATENT QFFIC ALEKSANDER MORAWSKI, F WARSAW,.RUSSIA.

VACUUM-PUMP.

To all whom it may concern:

Be it known that I, ALEKSANDER MoRAw- SKI, a subject of the Czar of Russia, and resident of lVarsaw, in the Empire of Russia, have invented certain new and useful Improvements in and Relating to Vacuum- Pumps, of which the following is a specification.

This invention has for its object to furnish a new type of vacuum pump in which use is made of an upright cylinder, which is partly filled with mercury or other sealing liquid, and closed at its upper end, and in which a piston is reciprocated by suitable mechanism, so that vacuum work is done during its upward and downward stroke, while the sealing liquid, which is placed in the bottom of the cylinder, is distributed in such a manner that all the sliding surfaces form a perfect joint, the operation of the pump being such that an exhaust-air conduit passes through the cylinder to near the bottom thereof and is surrounded by a deliverypipe which is moved out of the mercury covering the bottom of the cylinder upon the production of a suction-effect beneath the piston, while at the commencement of the delivery-stroke it is immersed in the Inercury, so that during the suction-stroke free access is afforded for the exhaust-air, while during the delivery-stroke the air drawn in is prevented from passing back into the exhaust-air conduit and is compelled to pass to the outside of the cylinder.

The principle of my improved vacuum pump, together with the details of construction of the same, is illustrated in the accompanying drawings, in which Figure l is a vertical central section through the improved vacuum pump, Fig. 2 is a plan-view of the cylinder-head, Fig. 3 is a plan of the intermediate cover below the cylinder-head, Fig. 4 is a plan-view of the bell-shaped piston, Fig. 5 is a detail vertical section through the cylinder-head and interior cover, Fig. 6 is a sectional sideview of the guide-pipe for the clamping member of the central delivery-pipe of the cylinder, and Fig. 7 is a detail horizontal section, on line 7, 7 Fig. 1, drawn on a larger scale, of the driver-bolt for the delivery-pipe.

Similar reference characters indicate corresponding parts in the different figures of the drawings.

The improved vacuum-pump consists of a base-frame l and a cylinder 2 supported Specification of Letters Patent.

Application filed April 6, 1911.

Patented Dec. 31,1912. Serial No. 619,262.

thereon, on which cylinder the mechanism for operating the pump is arranged. This unechamsm consists of a crank-shaft 3 supported in bearings of the base-frame 1,

' cranks 4 on the shaft 3, and connecting rods 5 which impart reciprocating motion to a cross-head 6 which slides up and down on the stationary rods 7 attached to the exterior lugs at the upper end of the cylinder 2. In the cylinder is arranged a fixed bellshaped body 42, which forms the bottom of the cylinder, in such a manner that an interval of some millimeters is left between the cylinder-wall 2 and bottom 42. In this interval a bell-shaped piston 43 is reciprocated, its conical head 44 being formed with a cup-shaped enlargement 46 at the apex above the throat 45. Between this throat 45 and a central sealed sleeve 47 a small interval is left. A suction pipe 15 passes through the head 17 and interior cover 16 into the pipe 47. The sealed sleeve 47 surrounds the suction-pipe 15 which carries a delivery-valve 16. The pipe 47 is formed at its upper end into a cup 48 which, as shown in Figs. 1 and 5, is connected with a clamplng member 27 on the head of the cylinder through the interior cover 16 and the head 17 of the cylinder. The clamping member 27 serves for intermittently raising or lowering the pipe 47 by its connection with the reciprocating cross-head 6, so that the lower end of the pipe 47 is alternately immersed into the mercury in the cup 55 of the bellsha ed bottom 42 during the downward stro e of the piston and lifted therefrom during the upward stroke.

The connection of the clamping member 27 with the cross-head 6 is made by a driver bolt 25 (Figs. 2 and 7) which is resiliently mounted in the cross-head 6, its end being able to enter into a recess 26 in the clamping member 27. The clamping member 27 em braces asleeve 28 connected with the pipe 15 which passes through the cover 17. As the clamping member 27 is adjustable in the head 17 of the cylinder in a guide-pipe 28, the interval between the lower end of the pipe' 15 and the level of the mercury, and also the movement of the central sealed sleeve 47, can be regulated. In addition to embracing the pipe 28, the clamping member 27 also embraces a pipe 29 fixed on the head 17 in such a manner that it is able to slide upon this pipe. At the commencement 1 of the upward movement of the piston, the

driver-bolt 25 displaces the clamping member 27 until a fixed stop 30 strikes against the conical head 31 of the bolt 25 and releases thereby the driver-bolt 25 from the clamping member 27. In the meantime, however, the clamping member 27 has come above the lower heel 32 of a spring-actuated lever 33 which is fulcrumed in the pipe 29, so that when the connection is disestablished the clamping member 27 is engaged by the heel 32. In this manner the lower end of the sealed sleeve L7 is maintained above the level of the mercury when the piston effects its upward stroke. When the piston has reached its highest position, a roller 34 arranged on the cross-head strikes against a heel 35 at the upper end of the lever 33 in such a manner that the lower heel 32 is moved inwardly into the pipe 29 and allows the clamping member 27 and the sealed sleeve 47 to descend. In this manner when the piston moves downward the sealed sleeve 47 is immersed in the mercury.

The bell-shaped piston 43 is provided at its upper part with a head 48 in which two cylindrical bores with hardened bushes 4:9 are provided, and the piston-rods are screwed at the base of the cylindrical bores into the head e8. To the inner cover 16 are attached two bush-like pistons 51, which correspond to the cylindrical bores in the head 48, and which pistons descend in the cylindrical bores in the intermediate cover 16. The bores in the cylinder 51 are closed at their upper ends by valves 52 which are normally closed by helical springs 54 is a nipple, shown in Fig. 2, for the discharge of the exhaust-air, which is fitted to the cylinder 2 immediately below the cover 16.

The operation of the vacuum pump shown in Figs. 1 to 7 is as follows: The bottom of the pump-cylinder is filled with mercury in which the bell-shaped piston 4L3 moves up and down. In the lowest position of the piston 4:3 the mercury flows over the upper face of the head 48* in such a manner that the vessel 46, and also the cylindrical recesses in the head e82 become filled with mercury. When the piston moves upward some mercury trickles from the vessel 46 between the throat 4:5 and the sealed sleeve 47, but the receptacle i6 is made of. such a size that in the highest position of the piston the mercury is still able to overflow into the cup L8 in such a manner that a good joint is formed by the mercury in the space between the pipes 15 and sealed sleeve 47. When the piston moves upward the sealed sleeve 47 is lifted out of the cup 55 filled with mercury, while when the pis ton descends it is lowered into the vessel. When the cylinder-pistons 51 enter the cylindrical bores in the head 48 of the piston 43, the latter approaches the intermediate cover 16 and the mercury contained in the recesses is forced into the space above the cover 16 in opposition to the spring-actuated valves 52 and distributed by the passages 50 so as to form a good joint for the sliding surfaces. Nhile the exhaust-air is drawn into the space below the piston through the pipe 15, upon the ascent of the piston, and upon the descent of the piston it is forced through the mercury in the cupshaped enlargement 46 into the space above the piston, as in the arrangement illustrated in Fig. 1 the air cannot be forced above the interior cover 16. The air con ducted above the piston is drawn off through the nipple 5 L by an auxiliary pump of the kind which is usually employed in vacuumpumps as heretofore constructed to render the main pump C'fllClQllt in practice.

In the form of pump described, the selection of a suitable material is of the greatest importance. This material must be a nonoXidiZing metal, such as cobalt or nickel, and those parts which permanently contact with the mercury and which are intended to form a joint therewith, must be formed of such a material that an ascending menicus results. These conditions are fulfilled by combinations or alloys of nickel, such as German silver or the like. It is therefore advisable that all parts coming into contact with the mercury should either be formed entirely of German silver, or like nickel compounds, or of steel with a coating of these metals.

I claim:

1. In a vacuum piston-pump, the combination with an upright cylinder, containing mercury in the bottom-part thereof, and having a head, an interior cover and an outmovable in the cylinder, piston-rods passing through the head and cover, a suction pipe passing through the head and cover and through the piston-head into the mercury, a central sealed sleeve surrounding the suction pipe, crank-driven means for reciproeating the piston, and means automatically controlled by the crank-driven means for lifting the sealed sleeve from the mercury when the piston ascends and allowing it to return into the mercury in the uppermost position of the piston.

2. In a vacuum piston-pump, the combination with a vertical cylinder containing mercury in the bottom-part thereof, and having a head, an interior cover and an outlet, of a bell-shaped piston having a perforated head movable in the cylinder, pistonrods passing through the head and cover, a suction pipe passing through the head and cover and through the piston-head into the mercury in the bottonrpart of the cylinder, a sealed sleeve surrounding the suction-pipe, spring-actuated valves in the piston-head, crank-driven means for reciproeating the piston, and means automatically controlled by the crank-driven means for lifting the sealed sleeve from the mercury when the piston ascends and allowing the sealed sleeve to return into the mercury when the piston is in the upper position.

3. In a vacuum piston-pump, the combination with a vertical cylinder containing mercury in the bottom-part thereof, and having a head, an interior cover and an outlet, of a bell-shaped piston having a perforated head movable in the cylinder, piston-rods passing through the cylinder and cover, a suction-pipe passing through the head and cover and through the pistonhead into the lower part of the cylinder, a sealed sleeve surrounding the suction-pipe, a cross-head connected with the piston-rods, a clamping member having connected with the sealed sleeve a spring-actuated driver-pin, a pin mounted in the cross-head and adapted to engage a recess of the clamping member when the piston is ascending and lift the sealed sleeve from the mercury, springactuated valves in the piston-head, means mounted on the cylinder-head for engaging the clamping member and holding it above the level of the mercury while the piston continues to rise, a member fixed on the cross-head for releasing said lifting means in the upper position of the piston, and means for reciprocating the cross-head.

4. In a vacuum pump, the combination with a vertical cylinder containing mercury in the bottom-part thereof and having a head, an interior cover and an outlet, of a pistonhaving a perforated head movable in the cylinder, piston-rods passing through the head and cover, an exhaustair pipe passing through the cover and cylinder-head, a sealed sleeve surrounding the exhaust-pipe and extending below the same into the mercury in the bottom-part of the cylinder, said interior cover being provided with valves traversed by the piston-rods, crank-driven means for reciprocating the piston, and means automatically controlled by the crankdriven means for lifting the scaled sleeve out of the mercury when the piston ascends and allowing said sleeve to return into the mercury in the upper position of the piston.

5. In a vacuum piston-pump, the combi nation with a vertical cylinder containing mercury in the bottom-part thereof and having a head, an interior cover and an outlet, of a piston having a perforated head movable in the cylinder, piston-rods passing through the head and cover, a suction pipe passing through the cover and through the piston-head, a sealed sleeve surrounding the suction pipe and extending below the same into the mercury in the bottom-part of the cylinder, said interior cover being provided with valves traversed by the piston-rods, crank-driven means for reciprocating the piston, means automatically controlled by said reciprocating means for lifting said sealed sleeve from the mercury when the piston ascends and allowing it to return in the upper position of the piston, and means for lifting the mercury into the space above the interior cover for forming a good joint between the suction-pipe and sealed sleeve.

6. In a vacuum pump, the combination with a vertical cylinder having a head, an interior cover, an outlet and a bottom in the form of a bell forming an annular space between the same and the side-wall of the cylinder and containing mercury in the annular space, of a piston comprising a bellshaped body movable in said annular space, a plurality of piston-rods passing through the head and interior cover, a suction-pipe passing through the cylinder-head and cover into the cylinder, a sealed sleeve surrounding the suction-pipe and extending from the piston-head into the upper part of the bottom, and means for reciprocating the piston.

7. In a vacuum-pump, the combination with a vertical cylinder having a head, an interior cover and an outlet, a bottom in the form of a bell forming an annular space between the same and the sidewall of the cylinder and containing mercury in said annular space, a piston comprising a bell-shaped body movable in said annular space and a perforated head, a plurality of piston-rods passing through the cylinder-head and cover, a central suction pipe passing through the head, cover and piston-head into the cylinder, a sealed sleeve surrounding the suction pipe and extending from the upper end of the bottom of the cylinder into the pistonhead, and means for reciprocating the piston, the piston-head having a plurality of cylindrical bores in the upper face thereof and said interior cover a plurality of pistons adapted to fit into said bores and force the mercury collected therein in the lowermost position of the piston out of the same for forming a mercury seal for the suction-pipe and sealed sleeve.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

ALEKSANDER MORAWSKI.

Witnesses:

FRANCIS TREMBIOKI, AUDREY KIRWAY.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G.

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